Middle Technical University Electrical Engineering Technical College Project Management Prepared by: Rawaa Dawood Salim Electrical Engineering Techniques college 2021/2022 Project Management Introduction, Objectives, Principles and Phases For Students of Fourth Stage Computer Department Department Of computer Engineering 1 Electrical Engineering Techniques college 2021/2022 1. Overview a. Target Population: For students of stage of second and fourth stage in technical Colleges and institutes in foundation of technical education. b. Rationale: Management is an art of directing workers efforts to obtain on high production and excellent quality. This leads to avoidance of loss and profits are increased and it provides security and safety element. This mode unit consists of main elements of management, objectives, and steps/phases of project management. c. Central Ideas: Project management is a set of principles, methods and steps for effective planning of objective-oriented work, thereby establishing a sound basis for effective scheduling, controlling and re-planning in the management of programs and projects. d. Objectives: The student will be able after finishing lecture on: - Define main elements of project management. - Study steps/phases of project management. 2. Pre-Test: 1. Define the term „project‟. 2. Organizing is done after planning in elements of management. State True or false 3. Project control is one of the step of project management- State True or False 4. The term “scope definition” in a steps of project management comes under a) Project initiation b) project planning c) project scheduling d) project costing 5. The term “client feedback” in a steps of project management comes under a) Project termination b) project planning c) project scheduling d) project costing Note: Check your answers in “Answer Keys” in end of mode unit. If you obtain 75% of solution, you cannot need to this mode unit. If your answer is poor, you will transfer to next page. 2 Electrical Engineering Techniques college 2021/2022 3. Theory: Introduction Project management emerged because of the growing demand for complex, sophisticated, customized goods and services and the exponential expansion of human knowledge. The former depends on the integration of product design with production / distribution and the latter allows a number of academic disciplines to contribute to the development of goods and services. Elements of management 1. Planning 2. Organizing involves: a. Establishing a structure to be filled by people, aimed at reaching the defined goals and objectives. b. Defining job content, interfaces, responsibilities, authority, and resource allocation. 3. Staffing involves: a. Filling the positions in the organizational structure with suitable people. b. Keeping the positions filled, in order to execute the plan. 4. Directing (or Leading) involves: a. Creating an environment in which individuals, working together in groups, can accomplish well-selected aims. b. Influencing people to contribute to reaching the goals and objectives. c. Using leadership styles, communication, conflict resolution, delegation, etc. in order to overcome the problems arising from people issues (attitudes, desires, motivations, behavior in groups, etc.) on a project. 5. Controlling (and co-ordination) involves: a. Measuring actual performance. b. Comparing actual- with desired results and implementing corrective actions – e.g. by controlling the actions of the people doing the work. 3 Electrical Engineering Techniques college 2021/2022 Fig. (1) Block diagram of elements of management. Project is an assignment/task/job that has to be undertaken and completed within a set time, budget, resources and performance specifications designed to meet the needs of stakeholder and beneficiaries. Project Management is the use of knowledge, skills, tools, and techniques to plan and implement activities to meet or exceed stakeholder needs and expectations from a project. Project Management is a set of principles, methods and techniques for effective planning of objective-oriented work, thereby establishing a sound basis for effective scheduling, controlling and re-planning in the management of programs and projects. In other words, it provides an organization with powerful tools that improve the organization's ability to plan, organize, implement and control its activities and the ways it uses its people and resources. 4. Self- Test 1. Define project management. 2. List the main elements of management. Objectives of the Project management The basic purpose for initiating a project is to accomplish some goals. The reason for organizing the task as a project is to focus the responsibility and authority for the attainment of the goals on an individual (project manager) or a small group (project team). Project Management is a means by which to fit the many complex pieces of the project puzzle together, both human and technical, by use of: - Schedules - Budgets, including resource allocation 4 Electrical Engineering Techniques college - 2021/2022 Scope (product) definition Project Management fulfills two purposes: 1. Technical: Documentation techniques to communicate - The 'plan' - Status which compares 'planned' versus 'actual' performance 2. Human: Managerial skills to be a better 'manager' of people as well as the project Implementation of project management technique can have significant results such as: 1. Cost reduction 2. Time reduction 3. Recourses allocation 4. Increased quality 3. Project management fulfills two purposes --------- and -------------. 4. Implementation of project management technique leading to --------, ---------, --------, and -------. Steps/Phases of Project Management The steps followed for project management are essentially the steps for successful project initiation, development and completion. 1. PROJECT INITIATION - Concept definition, which includes identification and selection of opportunities and identification of objectives - Feasibility study and justification 2. PROJECT PLANNING - Scope definition - Goal definition, includes time, money, resources and product targets - Project requirements - definition of deliverables - Project objectives - definition of major work efforts, quantifiable - Work break down structure - Analysis & break down of project into smaller pieces of work - Development of checklist of everything that needs to be done - Team building - Selection of project manager 5 Electrical Engineering Techniques college 2021/2022 - Selection of team members, - Use resource matrix to match skills task requirements 3. PROJECT SCHEDULING - Determining sequence of work - Building network / interdependence - Analysis of interdependence, estimation of total duration (CPM, PERT) and determination of Critical Path - Establish milestones - Graph on time chart (Gantt chart) - Determining human resource loading - Establishing milestones / reporting periods 4. PROJECT COSTING - Estimate costs, capital / operating - Develop cost spreadsheets 5. PROJECT CONTROL - Done periodically (at milestones) - Time control, status, deviations from plan, replanning, new estimates - Cost control, Expenditure, deviations from plan, new estimates - Quality control, performance versus performance criteria / project requirements 6. PROJECT TERMINATION / EVALUATION - Post project activity - Statistics from monitoring progress - Client feedback - Profitability or not of the project - Post implementation report 5. The term “team building” in a steps of project management comes under a) Project termination b) project planning c) project scheduling d) project imitation Note: Check your answers in “Answer Keys” in end of mode unit. 6 Electrical Engineering Techniques college 2021/2022 5. Post- Test 1. List the steps/phases of project management. 2. Controlling is last element of elements of management. State True or False 3. Implementation of project management leads to increase the cost- State True or False 4. Project Management is a means by which to fit the many complex pieces of the project puzzle together, both human and technical, by use of --------,----------, and ----------. 5. The term “establish milestones” in a steps of project management comes under a) Project termination b) project planning c) project scheduling d) project costing 6. References 1. Y. Bakouros and V. Kelessidis “Project management” INNOREGIO: dissemination of innovation and knowledge management techniques, January 2000. Answer Keys 2. J.R. Meredith and S.J. Mantel “Project Management”, J. Wiley & Sons, 1995. 3. http://www.projectmanagement.com/main.htm. 7 Electrical Engineering Techniques college 2021/2022 Pre- Test 1. Project is an assignment/task/job that has to be undertaken and completed within a set time, budget, resources and performance specifications designed to meet the needs of stakeholder and beneficiaries. 2. True. 3. True. 4. b) project planning 5. a) project termination Self-Test 1. Project Management is the use of knowledge, skills, tools, and techniques to plan and implement activities to meet or exceed stakeholder needs and expectations from a project. 2. Planning, organizing, staffing, directing, and controlling. 3. Technical and human. 4. Cost reduction, time reduction, recourses allocation, and increased quality. 5. b) project planning Post- Test 1. Project initiation, project planning, project scheduling, project costing, project control, and project termination. 2. True. 3. False. 4. Schedules, budgets, including resource allocation, and scope (product) definition 5. c) project scheduling 8 Electrical Engineering Techniques college 2021/2022 Planning and Control in Projects: Planning Scheduling Controlling For Students of Fourth Stage Computer Department Department Of Computer Engineering 8 Electrical Engineering Techniques college 2021/2022 1. Overview a. Target Population: For students of stage of second and fourth stage in technical Colleges and Institutes in foundation of technical education. b. Rationale: Project planning is a critical element of every successful investment. It provides a foundation on which to base anticipated efforts. Additionally, it helps identify investment components and illustrates these components in a project plan. a. Central Ideas: The basic purpose of a planning and control in projects is to help managers schedule, monitor and control large and complex projects. b. Objectives: The student will be able after finishing lecture on: - Define planning, scheduling and control processes. - Study the main steps of planning, scheduling and control processes in projects. 2. Pre-Test: 1. Define the term “scheduling process”. 2. Contingency needs to be allowed both on the estimated effort and elapsed time because of the likelihood of unforeseen work arising. State True or False 3. The role of the project manager falls into three areas ------, -------- and ------. 4. ------------- is the process of comparing actual performance with planned performance, analyzing the differences, and taking the appropriate corrective action. 5. Planning process is closest to mean for: a) Project Scope Management b) Project Time Management c) Project Cost Management d) Project Quality Management Note: Check your answers in “Answer Keys” in end of mode unit. If you obtain 75% of solution, you cannot need to this mode unit. If your answer is poor, you will transfer to next page. 9 Electrical Engineering Techniques college 2021/2022 3. Theory: Introduction Planning This process performed to define and mature the project scope, develop the project management plan, and identify and schedule the project activities that occur within the project. Scheduling Scheduling is the process of determining when project activities will take place depending on defined durations and precedent activities. Schedule constraints specify when an activity should start or end based on duration, predecessors, external predecessor relationships, resource availability, or target dates. Control Control is the process of comparing actual performance with planned performance, analyzing the differences, and taking the appropriate corrective action. 4. Pre-Test: 1. Define the term “planning process”. 2. Scheduling is the process of determining when project activities will take place depending on defined ---------- and ------------. Project Planning and Scheduling Project Planning begins as soon as Definition allows. The process involves planning subprojects first and hence Definition must at least have identified the sub-projects and the major tasks involved in them. From this point, Planning and Definition tend to continue in parallel as a series of iterations, gradually refining and hardening both Definition and Plans. The purpose of the Project Plan at this stage is to provide detailed realistic estimates of time, duration, resource and cost, and planning should be carried out only in sufficient detail to allow this to be achieved. Detailed planning for allocation of tasks to individuals is carried out progressively as the work proceeds. 10 Electrical Engineering Techniques college 2021/2022 Where there are sub-projects these should be planned first and then combined to produce the overall project plan. Produce a plan for each sub-project, or for the total project if there are no sub-projects as follows: 1. Identify Major Activities Break the work down into activities of the order of 20-50 days of effort, ensuring that milestones correspond to completion of one or more of these. In practice the achievement of a milestone is usually a good basis for identifying an activity e.g. “prepare and perform user training”. 2. Identify and Chart Dependencies Produce a network chart for the sub-project showing dependencies between the major activities and dependencies on other sub-projects or external events. 3. Estimate Effort and Duration Estimate effort and duration of each major activity. 4. Provide Contingency At this stage estimates are likely to be 'soft' and probably expressed in ranges, because precise details of the work are not settled. Contingency needs to be allowed both on the estimated effort and elapsed time because of: • The likelihood of unforeseen work arising, • The likelihood that tasks will take longer than expected, • The likelihood of changes to requirements or plans before publication. (Subsequent changes should be processed through Change Control). Contingency provision should remain evident in plans (probably as one or more contingency 'tasks'). This provision should then progressively be removed from plans during Tracking and Control as a result of either: • being used up by e.g. tasks taking longer than planned, • or reaching a point where uncertainty is reduced such that a part of contingency provision can safely be deleted. This usually means the deletion of contingency allowed, but not used, on tasks now completed. 5. Schedule Major Activities Determine start and end dates for each major activity and produce a bar chart or other diagram, showing relationships between activities. 6. Calculate Resource Requirements Calculate requirements for each time period. Identify needs for each resource type (e.g. systems analyst, user staff) and identify needs for special skills or scarce resources. 11 Electrical Engineering Techniques college 2021/2022 7. Calculate Costs Calculate costs for the sub-project. This should include 'hardening up' items such as cabling, training etc., for which an order of costs had been produced previously. 8. Determine Overall Costs and Benefits of the Project The cost/benefit justification should have already been stated in the feasibility study. This stage provides the opportunity to review the case in the light of more detailed information. 9. Document the Project Plan Once a viable plan has emerged (i.e. conflicts have been resolved, resource availability has been confirmed etc.) the Project Manager should produce the Project Plan covering: • Project Schedule. This should show major activities by sub-project on a bar chart or other diagram. The chart should also show project milestones and target dates. Show contingency as a single provision at the end. Include an overall project network showing the critical path. Narrative explanation may be included for clarification. • Major Check points and Reviews. List the dates of Checkpoint Reports, Checkpoint Meetings, Steering Group Meeting and the Post-Implementation Review. • Deliverables. List the major products of the project with delivery dates and acceptance procedures. • Resources. Summarise the resource needs from the sub-project plans. • Costs and Benefits figures. Revise and refine as a result of completion of Definition and Planning. • Potential Problems. List any risks, problems or assumptions which may jeopardize the Plan, together with actions needed to correct the situation. 10. Ensure Management Systems are in place. 3. Contingency needs to be allowed both on the estimated effort and elapsed time because of the likelihood that tasks will take longer than expected. State True or False 4. Systems analyst and user staff come under “Calculate Resource Requirements” State True or False Project Implementation and Control The role of the project manager falls into three areas: i) Management of stakeholders ii) Management of the project life cycle iii) Management of performance 12 Electrical Engineering Techniques college 2021/2022 An approach needs to be developed for each of these. Control and monitoring procedures need to be put in place and appropriate information systems developed. The procedures which are put into place can only be successful if: a) there is satisfactory information to enable the team to manage the project effectively; b) they are simple and easy to operate and understand; c) they have the full support of the project team. How should this relate to the three categories referred to above? i) Management of stakeholders: Stakeholders' interest must be monitored to ensure that: 1. their interest and support is maintained; 2. their views and ideas are being adequately reflected in the project development; 3. their personal success criteria are being pursued and achieved; 4. Environmental change is fully taken into account. ii) Management of the project life cycle: This is probably the most conventional view of project control. Feedback systems need to be set up to monitor key areas. The key areas would be as follows: 1. The project timetable, with particular reference to critical event times and potential bottlenecks. There should be feedback on activity times achieved and their effect on the whole project. If network analysis is used, then it is vital that the network is reworked and updated to take into account the actual performance achieved. 2. The project budget; budgetary control procedures can be used as in respect of any other form of budget. 3. Quality and performance standards; these need to be monitored against the original project specification subject to changes agreed with stakeholders in the course of project development. Where possible this should all be done through positive reporting which will require action to be taken. iii) Management of performance: This is the least tangible but possibly the most important of the three categories. How it is tackled will depend upon what kind of project is being carried out. It is unlikely that the project team will spend all of their working time together in close proximity and under the direct supervision of the project manager. It is much more likely that they will work apart most of the time, only meeting up occasionally and only meeting with the project manager from time to time. Control issues that need to be considered therefore would be: 13 Electrical Engineering Techniques college 2021/2022 1. How to get the best out of the team when they are together. If you are holding meetings then they should be purposeful and effective. They should not simply be part of the routine. Having said that, they may be an important element in binding the team together and in developing a team approach to planning and monitoring of performance. 2. Ensuring people work when the team is apart. You need to set people realistic deadlines and ensure that they see the importance of their contribution and that their contribution is fully valued. 3. Communications are important in terms of disseminating information and keeping everyone informed. There are views that team members should be given information on a need to know basis but this approach can cause problems. 4. Ensuring continuing commitment by the team and adherence to the values and beliefs being pursued by the team. 5. Change, in particular, needs to be communicated to team members quickly and effectively. It is important to stress once again the need to look at the team and also for the project leader to look inwards at his or her own performance. 5. The term “scope definition” in a steps of project management comes under a) Project initiation b) project planning c) project scheduling d) project costing 5. Post- Test 1. Define the term ”control process” 2. List briefly the points that the manager should produce to cover “Document the Project Plan”. 3. The role of the project manager falls into three areas ------, -------- and ------. 4. Planning process performed to define and mature the ---------. 5. Identify and Chart Dependencies les under: a) Planning process b) Control process c) Planning and scheduling process d) Staffing process Note: Check your answers in “Answer Keys” in end of mode unit. 14 Electrical Engineering Techniques college 2021/2022 6. References 1. Principles of Project Management, NPC publication 2. S. Choudhury “Project Management”, Tata McGraw Hill – 2003 3. Y. Bakouros and V. Kelessidis “Project management” INNOREGIO: dissemination of innovation and knowledge management techniques, January 2000. 4. http://www.projectmanagement.com/main.htm Answer Keys Pre- Test 1. Scheduling is the process of determining when project activities will take place depending on defined durations and precedent activities. Schedule constraints specify when an activity should start or end based on duration, predecessors, external predecessor relationships, resource availability, or target dates. 2. True. 3. management of stakeholders, management of the project life cycle and management of performance 4. Control process 5. a) Project Scope Management Self-Test 1. Planning: This process performed to define and mature the project scope, develop the project management plan, and identify and schedule the project activities that occur within the project. 2. Durations and precedent activities. 3. True 4. True 5. b) project planning Post- Test 1. Control is the process of comparing actual performance with planned performance, analyzing the differences, and taking the appropriate corrective action. 2. • Project Schedule. • Major Check points and Reviews. • Deliverables. • Resources. • Costs and Benefits figures. • Potential Problems. • Appendices. 3. management of stakeholders, management of the project life cycle and management of performance 4. project scope 5. a) Planning and scheduling process 15 Electrical Engineering Techniques college 2021/2022 16 Electrical Engineering Techniques college 2021/2022 Project Planning Techniques Network analysis Critical Path Method (CPM) For Students of Fourth Stage Computer Department Department Of computer Engineering 23 Electrical Engineering Techniques college 2021/2022 1. Overview a. Target Population: For students of stage of second and fourth stage in technical Colleges and institutes in foundation of technical education. b. Rationale: The most common and widely used project management technique that can be classified under the title of Network Analysis is Critical Path Method (CPM). It was developed in the 1950's to help managers schedule, monitor and control large and complex projects. CPM was first used in 1957 to assist in the development and building of chemical plants within the DuPont corporation. a. Central Ideas: The basic purpose of a network analysis is to help managers schedule, monitor and control large and complex projects. b. Objectives: The student will be able after finishing lecture on: - Define Critical Path Method (CPM). - Study steps of CPM. 2. Pre-Test: 1. Define the term ‗CPM. 2. CPM predicts the time required to complete the project— State True or False 3. The time between its earliest and latest start time, or between its earliest and latest finish time of an activity is a) delay time b) slack time c) critical path d) start time 4. The path through the project network in which none of the activities have slack is called a) start time b) slack time c) critical path d) delay time 5. Activity is an ------------- needed for the completion of a project. Note: Check your answers in ―Answer Keys‖ in end of mode unit. If you obtain 75% of solution, you cannot need to this mode unit. If your answer is poor, you will transfer to next page. 24 Electrical Engineering Techniques college 2021/2022 3. Theory: Introduction Critical Path Method (CPM) or (Calculate Schedule) is a modeling process that defines all the project's critical activities which must be completed on time. CPM models the activities and events of a project as a network. Steps in CPM Project Planning 1. Specify the individual activities. 2. Determine the sequence of those activities. 3. Draw a network diagram. 4. Estimate the completion time for each activity. 5. Identify the critical path (longest path through the network) 6. Update the CPM diagram as the project progresses. CPM Benefits • Provides a graphical view of the project. • Predicts the time required to complete the project. • Shows which activities are critical to maintaining the schedule and which are not. Critical path is the longest-duration path through the network. The significance of the critical path is that the activities that lie on it cannot be delayed without delaying the project. Because of its impact on the entire project, critical path analysis is an important aspect of project planning. The critical path can be identified by determining the following four parameters for each activity: 1. Earliest Start time (ES): the earliest time at which the activity can start given that its precedent activities must be completed first. 2. Earliest Finish time (EF), equal to the earliest start time for the activity plus the time required completing the activity. 3. Latest Finish time (LF): the latest time at which the activity can be completed without delaying the project. 4. Latest Start time (LS), equal to the latest finish time minus the time required to complete the activity. 25 Electrical Engineering Techniques college 2021/2022 4. Self-Test: \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\ 1. Define the term ―critical path‖. 2. List the benefits of CPM. The slack time or Total float for an activity is the time between its earliest and latest start time, or between its earliest and latest finish time. Slack is the amount of time that an activity can be delayed past its earliest start or earliest finish without delaying the project. The critical path is the path through the project network in which none of the activities have slack, that is, the path for which ES=LS and EF=LF for all activities in the path. A delay in the critical path delays the project. Similarly, to accelerate the project it is necessary to reduce the total time required for the activities in the critical path. Activity is an individual task needed for the completion of a project. Duration is the length of time (hours, days, weeks, months) needed to complete an activity. Float is the amount of time that an activity can slip past its duration without delaying the rest of the project. Free float is the excess time available before the start of the following activity. 3. The time between its earliest and latest start time, or between its earliest and latest finish time of an activity is a) delay time b) slack time c) critical path B bActivity on arrow (A.) d) start time 4. ------------ is the longest-duration path through the network. Activity on arrow (A.O.A) Examples Ex1: Determine the critical path by using CPM of the following Table (project), Activities A B C D E Path 1─2 2─3 2─4 3─5 4─5 Duration (day) Description 3 3 وصف مختصر لكل 1 فعالية 2.5 2 Ans: 26 Electrical Engineering Techniques college 2021/2022 Critical path =3+ 3+ 2.5= 8.5 days Ex2: Determine the critical path by using CPM of the following Table (project), Activities A B C D E F G Path 1─2 1─3 3─5 3─4 2─4 5─6 4─6 Duration (week) Description 1 4 3 وصف مختصر 5 لكل فعالية 2 3 6 Ans: Critical path= 4+ 5+ 6= 15 weeks 27 Electrical Engineering Techniques college 2021/2022 Dummy Activity: An imaginary activity that requires no time and is used to correctly maintain the appropriate precedence relationships. 5. Determine the critical path by using CPM of the following Table (project), Activities A B C D E Path 1─2 2─3 3─4 3─5 5─6 Duration (day) 2 3 8 5 4 Description تحضير الموقع تخطيط الموقع انشاء االعمدة بناء الجدران الخارجية بناء السقف 5. Post- Test 1. What is slack time in critical path in CPM? 2. Which of the following statements about critical path analysis (CPA) is true? a) The critical path is the longest path through the network b) The critical path is the shortest path through the network c) Tasks with float will never become critical d) The network should remain constant throughout the project 3. In Critical Path of CPM used in project planning techniques indicates-------------. a) time require for the completion of the project b) delays in the project c) early start and late end of the project noneyour of theanswers above in ―Answer Keys‖ in end of mode unit. Note:d)Check 4. Dummy Activity is an imaginary activity that requires no time and is used to correctly maintain the appropriate precedence relationships. State True or False 5. Determine the critical path by using CPM of the following Table (project), Activities A B C D E Path 1─2 2─3 2─4 3─5 4─5 Duration (day) 3 3 1 2.5 2 Description وصف مختصر لكل فعالية Note: Check your answers in ―Answer Keys‖ in end of mode unit. 6. References 1. Principles of Project Management, NPC publication 2. S. Choudhury ―Project Management‖, Tata McGraw Hill – 2003 3. W. Durfee and T. Chase, ―Project Management - Gantt Chart Tutorial‖ University of Minnesota, 2003 4. http://www.projectmanagement.com/main.htm 28 Electrical Engineering Techniques college 2021/2022 Answer Keys Pre- Test 1. Critical Path Method (CPM) or (Calculate Schedule) is a modeling process that defines all the project's critical activities which must be completed on time. CPM models the activities and events of a project as a network. 2. True. 3. b) slack time 4. c) critical path 5. individual task Self-Test 1. Critical path is the longest-duration path through the network. The main objective of a Gantt chart is to assess how long a project should take and to establish the order in which tasks need to be carried out by the ending of the project. 2. • Provides a graphical view of the project. • Predicts the time required to complete the project. • Shows which activities are critical to maintaining the schedule and which are not. 3. b) slack time 4. Critical path 5. Post- Test 1. The slack time or Total float for an activity is the time between its earliest and latest start time, or between its earliest and latest finish time 2. a) The critical path is the longest path through the network 3. a) time require for the completion of the project 4. True 5. 29 Electrical Engineering Techniques college 2021/2022 Activity on anode (A.O.N) ACTIVITY E.s E.f L.s L.f DURATION Example 3:- by using activity on Node(A.O.N) Determine the critical path by using CPM of the following Table (project), Activities A B C D E F G Preceded by None A A B, C B D E,F Duration (week) Description 1 4 3 DESCIPTION 5 OF ACTIVITY 2 3 6 Solution:E B A 4 C D F e PATH1:-A,B,E,G=1,4,2,6=13 WEEKS PATH 2:-A,B,D,F,G=1,4,5,3,6=19 WEEKS PATH3:- A,C,D,F,G=1,3,5,3,6=18 WEEKS CRTICAL PATH=19 WEEKS 30 G Electrical Engineering Techniques college 2021/2022 31 Electrical Engineering Techniques college 2021/2022 32 Electrical Engineering Techniques college 2021/2022 33 Electrical Engineering Techniques college 2021/2022 34 Electrical Engineering Techniques college 2021/2022 35 Electrical Engineering Techniques college 2021/2022 EX:-for the following table of the network below draw the network And calculate the cp(critical path) and T.f (total float). Activity A B C D E F G H Duration 5 6 8 10 7 5 4 10 Preceded by None A A A B,C,D B,E F,D B,F,G T.F 0 4 2 0 0 0 0 0 C.P 41 41 41 41 41 41 Solution:-Activity on anode (A.O.N) 5 B 11 0A5 055 9 6 15 1212 5 C 13 7 8 15 9 5 12 5 D 15 31 H 41 2 2 F 27 15 E 22 2 2 5 27 15 7 22 5 10 15 Cp=A,D,E,F,G,H=5+10+7+5+4+10=41 36 27 G 31 27 4 31 31 10 41 Electrical Engineering Techniques college 2021/2022 EX:- find the c.p from figure below. Solution:Path1=A, D, H, J=2+5+7+4=18 Path2=B, E, H, J=3+6+7+4=20 =cp Path3=B, F, J=3+4+5=12 Path4=C+G+I+J=4+7+3+4=18 37 Electrical Engineering Techniques college 2021/2022 Project Planning Techniques Program Evaluation and Review Technique (PERT) For Students of Fourth Stage Computer Department Department of computer Engineering 30 Electrical Engineering Techniques college 2021/2022 1. Overview a. Target Population: For students of stage of second and fourth stage in technical Colleges and institutes in foundation of technical education. b. Rationale: PERT is a technique for estimating and planning a large project. One of its most powerful concepts is that project management is the management of probabilities. PERT makes use of simple statistical mathematics in order to come up with a probability distribution for the completion dates of the project milestones. c. Central Ideas: The basic purpose of a PERT is to implement huge projects involving thousands of contractors and reduce both the time and cost required to complete a project. d. Objectives: The student will be able after finishing lecture on: - Define Program Evaluation and Review Technique (PERT). - Study steps of PERT. 2. Pre-Test: 1. There are three techniques to plan the project --------, --------- and ---------. 2. What is meaning with optimistic time ( ) 3. Define the term „PERT‟. 4. A strategic analysis of a PERT network concentrates on the allocation of resources to reduce the time on the critical path. State True or False 5. Project management technique which uses three time estimates-optimistic, pessimistic and most likely, which help in establishing the probability of completing a project within a specified time and take calculated risk before commencing a project is---------. a) PERT (b) Gantt chart (c) CPM (d) none of the above Note: Check your answers in “Answer Keys” in end of mode unit. If you obtain 75% of solution, you cannot need to this mode unit. If your answer is poor, you will transfer to next page. 31 Electrical Engineering Techniques college 2021/2022 3. Theory: Introduction The Program Evaluation and Review Technique (PERT) is a network model that allows for randomness in activity completion times. PERT uses three time estimatesoptimistic, pessimistic and most likely, which help in establishing the probability of completing a project within a specified time and take calculated risk before commencing a project. It has the potential to reduce both the time and cost required to complete a project. What are the different steps involved in PERT planning? PERT planning involves the following steps: 1. Identify the specific activities and milestones. 2. Determine the interdependencies and proper sequence of the activities. 3. Construct a network diagram. 4. Estimate the time (three time estimates, if probabilities are to be computed) required for each activity. 5. Determine the critical path. 6. Update the PERT chart as the project progresses. What are the benefits of PERT? PERT is useful because it provides the following information: • Expected project completion time. • Probability of completion before a specified date. • The critical path activities that directly impact the completion time. • The activities that have slack time and that can lend resources to critical path activities. • Activity starts and end dates. 4. Self-Test: 1. It has the potential to reduce both the --------- and ---------- required to complete a project. 2. Of all paths through the network, the critical path a) has the maximum expected time. b) has the minimum expected time. c) has the maximum actual time d) has the minimum actual time. 32 Electrical Engineering Techniques college 2021/2022 Estimate activity times A distinguishing feature of PERT is its ability to deal with uncertainty in activity completion times. For each activity, the model usually includes three time estimates: • Optimistic time ( ) - generally the shortest time in which the activity can be completed. • Most likely time ( ) - the completion time having the highest probability. This is different from expected time. Seasoned managers have an amazing way of estimating very close to actual data from prior estimation errors. • Pessimistic time ( ) - the longest time that an activity might require. The expected time for each activity can be approximated using the following weighted average: Expected time ( = This expected time might be displayed on the network diagram. The standard deviation and variance for each activity are given by: 3. Define the term “Most likely time ( )”. 4. The standard deviation of an activity time is estimated as (b – a)/6, where b is the pessimistic and is the optimistic time. State true or false 5. The probability of completing the project by time T is equal to the probability of completing the critical path by time T. State true or false Ex: By Activities A B C D using path 1─2 1─3 2─4 3─4 PERT To 2 3 3 4 draw Tm 4 16 8 6 Tp 6 17 7 8 the network diagram and determine for the following Table. Assume D=23 weeks. Te 4 14 7 6 Ans: 33 S 0.6 2.3 0.6 0.6 V 0.36 5.29 0.36 0.36 ES 0 0 4 14 EF 4 14 11 20 LS 9 0 13 14 LF 13 14 20 20 C.P 9 0 9 0 20= 20= Electrical Engineering Techniques college √ 2021/2022 √ 5. Post- Test 1. What is meaning with pessimistic time ( ). 2. The calculation of the probability that the critical path will be completed by time T a) assumes that activity times are statistically independent b) assumes that total time of the critical path has approximately a beta distribution c) requires knowledge of the standard deviation for all activities in the network d) all of the above 3. The standard deviation of an activity time is estimated as (a – b)/6, where b is the pessimistic and a is the optimistic time. State True or false 4. Optimistic time ( ) - generally the shortest time in which the activity can be completed. 5. By using PERT draw the network diagram and determine ,slackfor the following Table. Assume D=38 weeks. Activities A B Path 1─2 1─6 To 2 2 Tm 5 5 Tp 14 8 C 2─3 5 11 29 D 2─4 1 4 7 E 3─5 5 11 17 F 4─5 2 5 14 G 6─7 3 9 27 H 5─8 2 2 8 I 7─8 7 13 31 Te S V ES EF LS LF Vc C.P Note: Check your answers in “Answer Keys” in end of mode unit. 6. References 1. J.R. Meredith and S.J. Mantel “Project Management”, J. Wiley & Sons, 1995. 2. http://www.projectmanagement.com/main.htm 34 Electrical Engineering Techniques college 2021/2022 Answer Keys Pre- Test 1. Gantt chart, CPM and PERT. 2. Optimistic time ( ) - generally the shortest time in which the activity can be completed. 3. PERT is a network model that allows for randomness in activity completion times. PERT uses three time estimates-optimistic, pessimistic and most likely, which help in establishing the probability of completing a project within a specified time and take calculated risk before commencing a project. 4. False. 5. a) PERT Self-Test 1. time and cost 2. a) has the maximum expected time. 3. Most likely time ( ) - the completion time having the highest probability. This is different from expected time. Seasoned managers have an amazing way of estimating very close to actual data from prior estimation errors. 4. True. 5. False. Post- Test 1. 2. 3. 4. 5. Pessimistic time ( ) - the longest time that an activity might require. a) assumes that activity times are statistically independent False Shortest time Activities A To 2 2 Tm 5 5 Tp 14 8 Te 6 S 2 B Path 1─2 1─6 V 4 ES 0 EF 6 LS 0 5 C 2─3 5 11 29 13 D 2─4 1 4 7 E 3─5 5 11 17 F 4─5 2 5 14 G 6─7 3 9 H 5─8 2 2 I 7─8 7 13 LF 6 slack 0 1 1 4 16 0 5 6 19 2 7 2 6 19 0 4 1 11 2 1 6 4 19 10 20 24 14 30 19 30 6 2 4 0 10 16 24 30 14 27 8 11 4 3 1 16 5 16 7 18 2 1 30 33 30 33 31 0 15 4 16 16 31 18 33 2 √ 35 √ C.P = = = = Electrical Engineering Techniques college √ √ 2021/2022 Where D = 4 given in question 36 Electrical Engineering Techniques college 2021/2022 Crashing the project For Students of Fourth Stage Computer Department Department of computer Engineering 23 Electrical Engineering Techniques college 2021/2022 24 Electrical Engineering Techniques college 2021/2022 25 Electrical Engineering Techniques college 2021/2022 26 Electrical Engineering Techniques college 2021/2022 27 Electrical Engineering Techniques college 2021/2022 28 Electrical Engineering Techniques college 2021/2022 For example 29 Electrical Engineering Techniques college 2021/2022 EX: - the following data about the project tasks, network, and crash times/costs .calculate the cost of the project at all tie durations until you can no longer crash the project any further. Activity Preceded by Normal time(weeks) A B C D E F G None A A B C E D,F 5 10 13 3 5 10 5 Normal cost ($) 500 1200 3600 300 1000 2400 700 Crash time (weeks 4 6 11 1 4 8 5 Crash cost ($) 600 2000 4800 600 1400 5400 700 Solution:Activity Preceded by Normal time(week s) Normal cost ($) A* B C* D E* F* G* None A A B C E D,F 5 10 13 3 5 10 5 500 1200 3600 300 1000 2400 700 ∑ 9700 $ Crash time (weeks 4 6 11 1 4 8 5 Crash cost ($) Allowable crash time =tn-tc 600 2000 4800 600 1400 5400 700 Slope(cost/time)= cc-cn/tn-tc 1 4 2 2 1 2 0 Slope for activity (A)= cc-cn/tn-tc ( 600 - 500 )/(5 - 4 )= 100 Slope for activity (B)= cc-cn/tn-tc ( 2000 - 1200 Slope for activity (C)= cc-cn/tn-tc (4800 - 3600 Slope for activity (D)= cc-cn/tn-tc ( 600 Slope for activity (E)= cc-cn/tn-tc (1400 Slope for activity (F)= cc-cn/tn-tc ( 5400 - 2400 )/(10 -8 )=1500 Slope for activity (G)= cc-cn/tn-tc (700 - 700 )/( 5-5 )=0 30 - 300 - 1000 )/( 10 - 6 )= 200 )/( 13 - 11 )=400 )/(3 -1 )=150 )/(5 400 100 200 600 150 400 1500 0 Electrical Engineering Techniques college 2021/2022 Draw the project by using( A.O.N) Find C.p 31 Electrical Engineering Techniques college 2021/2022 Crash activity choose the small value in slope in cp path First crashing activity ( A ) ( 1 ) week cost=9700+100=9800$ Duration = 4 weeks c.p=37 weeks First 32 Electrical Engineering Techniques college 2021/2022 Crash activity choose the small value in slope in cp path Crashing activity ( E ) (1) week cost=9800+400=10200$ Duration = 4 weeks c.p=36 weeks 33 Electrical Engineering Techniques college crashing activity ( 2021/2022 c ) (1 ) week cost=10200+ 600=10800$ Duration = 12 weeks c.p=35 weeks Crashing activity ( C ) (1 ) week Duration = 11 weeks cost=10800+600=11400$ c.p=34 weeks 34 Electrical Engineering Techniques college 2021/2022 35 Electrical Engineering Techniques college 2021/2022 Crash activity choose the small value in slope in cp path Crashing activity ( f ) (1 ) week Duration = 9 weeks cost=11400+1500=12900 c.p=33 week 36 Electrical Engineering Techniques college 2021/2022 Crash activity choose the small value in slope in cp path crashing activity ( F ) ( 1 ) week cost=12900+ 1500 =14400$ Duration = 8weeks c.p=32 weeks 37 Electrical Engineering Techniques college 2021/2022 EX:- using table below of activities assume the following normal duration /cost and crash duration/cost Draw the network and find the cp and crash the project (4 weeks) and determine the total cost. Activity path 1-2 1-3 2-4 2-5 3-4 4-5 Solution Normal Normal time(weeks) cost ($) 8 100 4 150 2 50 10 100 5 100 3 80 Crash time (weeks) 6 2 1 5 1 1 Crash cost ($) 200 350 90 400 200 100 activity Normal Normal time(weeks) cost ($) Crash time (weeks) Crash cost ($) Allowable Slope(cost/time)= crash time cc-cn/tn-tc =tn-tc 1-2* 1-3 2-4 2-5* 3-4 4-5 8 4 2 10 5 3 6 2 1 5 1 1 200 350 90 400 200 100 2 2 1 5 4 2 100 150 50 100 100 80 50 100 40 60 25 10 ∑580$ Slope for activity (1-2)= cc-cn/tn-tc (200-100)/(8-6)=50 Slope for activity (1-3)= cc-cn/tn-tc (350-150)/(4-2)=100 Slope for activity (2-4)= cc-cn/tn-tc (90-50)/(2-1)=40 Slope for activity (2-5)= cc-cn/tn-tc (400-100)/(10-5)=60 38 Electrical Engineering Techniques college 2021/2022 Slope for activity (3-4)= cc-cn/tn-tc (200-100)/(5-1)=25 Slope for activity (4-5)= cc-cn/tn-tc (100-80)/(3-1)=10 8 Paths 1-2--5=18 c.p (critical path 1-2-4-5=13 1-3-4-5=12 Crash activity choose the small value in slope in cp path First crashing activity (1-2) (2) week cost= 580+2*50 Duration =6 weeks Cost=680$ The cp path after first crashing (1-2-5=16) Other path 1-2-4-5=11 1-3-4-5=12 Draw after crash (1-2) two week 39 Electrical Engineering Techniques college 2021/2022 Second crashing activity (2-5) (2) week cost= 680+2*60 Cost=800$ The cp path after first crashing (1-2-5=14) Other path 1-2-4-5=11 1-3-4-5=12 Draw after crash (2-5) two week 8 40 Electrical Engineering Techniques college 2021/2022 HW EX: - using table below of activities assume the following normal duration /cost and crash duration/cost Draw the network and find the cp and crash the project (2 days) and determine the total cost. Activity Preceded by Crash Normal A B C D E F G A,B C C C D,E,F Time(day) 10 12 11 5 8 9 8 41 Cost($) 5000 1200 3600 300 1000 2400 700 Time(day) 10 11 9 4 6 7 7 Cost($) 5000 1300 4800 600 2000 5400 1000 Electrical Engineering Techniques college 2021/2022 Cost Account Methods (Break Even Analysis Method) For Students of Fourth Stage Computer Department Department of computer Engineering 44 Electrical Engineering Techniques college 2021/2022 1. Overview a. Target Population: For students of stage of second and fourth stage in technical Colleges and institutes in foundation of technical education. b. Rationale: Costing means looking at the amount to be spent on selling a product, running a production process or delivering a service. This mode unit introduces of classification of costs according variability in order to select the suitable method to determine the selling price. c. Central Ideas: The basic purpose of classification of costs to determine the most suitable method of accumulating and allocating costs. d. Objectives: The student will be able after finishing lecture on: - Classify the cost according the variability. - Determine the BEP and its effect on the costs. 2. Pre-Test: 1. The examples of semi-variable costs include; ---------, -------- and ---------. 2. The ------------ method is used to calculate the cost according the variability. 3. Material cost is considered from variable costs. State True or False 4. Define the term „Fixed cost‟. 5. For the following data: Fixed cost = 400,000 ID Variable cost per unit = 20 ID Selling price per unit=100 ID Estimating profit = 300,000 ID a- Calculate sales value. b- Calculate the contribution if the total sales 950,000 ID. Note: Check your answers in “Answer Keys” in end of mode unit. If you obtain 75% of solution, you cannot need to this mode unit. If your answer is poor, you will transfer to next page. 45 Electrical Engineering Techniques college 2021/2022 3. Theory: Introduction The cost is classified by variability to: 1. Variable Costs - Variable Costs: are costs which do vary directly with the level of output or production. Sometime are called direct costs. - Costs that change in total, directly in proportion to changes in the level of activities (volume). - The unit cost remains the same over a wide range of volume (referred to as the relevant range). - Relevant Range is the range of activity (production volume) within which variable unit costs are constant and fixed costs are constant and fixed costs are constant in total. In this range, the incremental cost of one additional unit of production is the same. - Examples include direct materials, direct labor, and part of manufacturing overhead. 2. Fixed Costs - Fixed Costs: are costs which do not vary directly with the level of output or production. Sometime are called indirect costs. - Costs that do not change in total regardless of changes in activity. - The unit cost decreases as volume increases. - Examples include rent, taxes, and insurance on manufacturing plant. 3. Semi-variable (Mixed) Costs - Costs that contain both variable and fixed costs. - Examples include: light, heat, and power. Breakeven Point: It is the relationship between a variable cost, fixed cost and volume of production (sales). No profit or loss at the breakeven point. Benefits of BEP 1. Forecasting profit at any volume of sales. 2. Giving clear image about relationship between costs and sales per unit. 3. Help management to make decisions. 46 Electrical Engineering Techniques college 2021/2022 4- Self-Test: 1. The technique used a variable and a fixed cost is called -----------. 2. Define the term „variable cost‟. Breakeven Point (BEP) Methods 1. Equation method - Operating profit = Sales - Total Fixed Costs - Total Variable Costs (Quantity x Unit Selling Price) (Quantity x Unit Variable Cost) Because at the breakeven point operating profit is zero, the equation can be as follows: - Sales = Total Fixed Costs + Total Variable Costs Where is a fixed cost, is a variable cost and is total sales. Ex1:For the following data: Fixed cost = 100,000 ID Variable cost per unit = 300 ID Selling price per unit=500 ID 1. Find number of unit (Units of Production) to verify BEP.جد عدد الىحداث الىاجب بيعها لتحقيق وفطت التعادل 2. Find BEP. جد وقطت التعادل 3. Find number of unit to obtain on operating profit of 1,000,000 ID. جد عدد الىحداث الىاجب بيعها لتحقيق مليىن ديىار ربح 4. Find the operating profit at production and selling 2,000 units.جد الربح المتحقق عىد اوتاج وبيع الفيه وحدة Ans: 1. Operating profit = Sales - Total Fixed Costs - Total Variable Costs Operating profit = 0 at BEP Sales = Total Fixed Costs + Total Variable Costs 2. 3. Operating profit = Sales - Total Fixed Costs - Total Variable Costs 4. Operating profit = Sales - Total Fixed Costs - Total Variable Costs 47 Electrical Engineering Techniques college 2021/2022 ( ) 3. Manufacturing company sells coats at 100 $ per unit .The variable cost is 30 $ per unit and total fixed are 21,000 $ require. a. Find Units of Production. b. What is the breakeven point? To calcu late sales value ) (قيمت المبيعاثat giving estimating profit, we used the following equation: Where is estimating profit. To calculate contribution )(المساهمت, we used the following equation: ( Where is contribution, is total sales and ) is selling price per unit. Ex2: For the following data: Fixed cost = 400,000 ID Variable cost per unit = 20 ID Selling price per unit=100 ID Estimating profit = 300,000 ID a- Calculate sales value. b- Calculate the contribution if the total sales 950,000 ID. Ans: 1. 2. ( ) ( ) 2. Chart method: Ex3: For the following data: Fixed cost = 40,000 ID Variable cost = 20,000 ID Sales =100,000 ID Calculate BEP by using chart method. Ans: 48 Electrical Engineering Techniques college 2021/2022 4. To calculate contribution, the following equation used . State True or False 5. Draw the BEP chart with labeling. 5. Post- Test 1. 2. 3. 4. 5. a. b. c. d. Define the term “BEP”. Examples of variable cost include rent, taxes, and insurance on manufacturing plant. Costs that contain both variable and fixed costs are called ----------. List benefits of BEP method. For the following data: Fixed cost = 60,000 ID Variable cost = 100,000 ID Sales =200,000 ID Calculate BEP Determine BEP at increasing in selling price 20% of sales value. Determine BEP at increasing 10% of fixed cost. Determine BEP atyour decreasing 20% variableKeys” cost. in end of mode unit. Note: Check answers in of “Answer Note: Check your answers in “Answer Keys” in end of mode unit. 6. References 1. J.R. Meredith and S.J. Mantel “Project Management”, J. Wiley & Sons, 1995. 2. http://www.projectmanagement.com/main.htm 49 Electrical Engineering Techniques college 2021/2022 3. Mike Holt, “Applying Overhead and Determining Break-Even Cost” Mike Holt Enterprises, Inc,2001, www.ecmweb.com 50 Electrical Engineering Techniques college 2021/2022 Answer Keys Pre- Test 1. 2. 3. 4. light, heat, and power. BEP method. True. Fixed Costs: are costs which do not vary directly with the level of output or production. Some time are called indirect costs. 5. ( ) ( ) Self-Test 1. breakeven point 2. Variable Costs: are costs which do vary directly with the level of output or production. Sometime are called direct costs. 3. Ans: 1. This means that to cover 21,000 $ of fixed costs, 300 units must be sold to break even. 2. OR 4. False. 5. 51 Electrical Engineering Techniques college 2021/2022 Post- Test 1. Breakeven Point: It is the relationship between a variable cost, fixed cost and volume of production (sales). No profit or loss at the breakeven point. 2. False. 3. mixed costs 4. - Forecasting profit at any volume of sales. - Giving clear image about relationship between costs and sales per unit. - Help management to make decisions. 5. ( ) ( ( ) ) 52 Limitation of Graphical Method Graphical solution is limited to linear programming models containing only two decision variables. Procedure Step I: Convert each inequality as equation Step II: Plot each equation on the graph Step III: Shade the ‘Feasible Region’. Highlight the common Feasible region. Feasible Region: Set of all possible solutions. Step IV: Compute the coordinates of the corner points (of the feasible region). These corner points will represent the ‘Feasible Solution’. Feasible Solution: If it satisfies all the constraints and non negativity restrictions. Procedure (Cont…) Step V: Substitute the coordinates of the corner points into the objective function to see which gives the Optimal Value. That will be the ‘Optimal Solution’. Optimal Solution: If it optimizes (maximizes or minimizes) the objective function. Unbounded Solution: If the value of the objective function can be increased or decreased indefinitely, Such solutions are called Unbounded solution. Infeasible (Inconsistent) Solution: It means the solution of problem does not exist. This is possible when there is no common feasible region. Example Max s.t. x2 8 7 z = 5x1 + 7x2 x1 < 6 2x1 + 3x2 < 19 x1 + x2 < 8 x1 , x2 > 0 6 5 4 Every point is in this nonnegative quadrant 3 2 1 1 2 3 4 5 6 7 8 9 10 x1 Example (Cont…) Max s.t. x2 8 7 6 x1 < 6 5 4 3 2 (6, 0) 1 1 2 3 4 5 6 7 8 9 10 x1 z = 5x1 + 7x2 x1 < 6 2x1 + 3x2 < 19 x1 + x2 < 8 x1 , x2 > 0 Example (Cont…) Max s.t. x2 z = 5x1 + 7x2 x1 < 6 2x1 + 3x2 < 19 x1 + x2 < 8 x1 , x2 > 0 (0, 6.33) 8 7 2x1 + 3x2 < 19 6 5 4 3 2 (9.5 , 0) 1 1 2 3 4 5 6 7 8 9 10 x1 Example (Cont…) x2 Max s.t. (0, 8) 8 7 x1 + x2 < 8 6 5 4 3 2 (8, 0) 1 1 2 3 4 5 6 7 8 9 10 x1 z = 5x1 + 7x2 x1 < 6 2x1 + 3x2 < 19 x1 + x2 < 8 x1 , x2 > 0 Example (Cont…) Max s.t. x2 x1 + x2 < 8 8 z = 5x1 + 7x2 x1 < 6 2x1 + 3x2 < 19 x1 + x2 < 8 x1 , x2 > 0 7 x1 < 6 6 5 4 3 2x1 + 3x2 < 19 2 1 1 2 3 4 5 6 7 8 9 10 x1 Example (Cont…) x2 8 7 6 (0,6.33) E 5 4 3 (5,3)D 2 (6,2)C 1 A (0,0) 1 (6,0)B 2 3 4 5 6 7 8 9 10 x1 Example (Cont…) Objective Function : Max Z= 5x1+7x2 Corner Points A – (0,0) B – (6,0) C – (6,2) D – (5,3) E – (0,6.33) Optimal Point : (5,3) Optimal Value : 46 Value of Z 0 30 44 46 44.33 Example Max Z=3 P1 + 5 P2 s.t. P1 < 4 P2 < 6 3 P1 + 2 P2 < 18 P1, P2 >0 Example Max Z=3 P1 + 5 P2 s.t. P1 < 4 P2 < 6 3 P1 + 2 P2 < 18 P1, P2 >0 P2 Every point is in this nonnegative quadrant P1 0 Example (Cont…) Max Z= 3 P1 + 5 P2 s.t. P1 < 4 P2 < 6 3 P1 + 2 P2 < 18 P1, P2 >0 P2 (0,0) (4,0) P1 Example (Cont…) Max Z= 3 P1 + 5 P2 s.t. P1 < 4 P2 < 6 3 P1 + 2 P2 < 18 P1, P2 >0 P2 (0,6) (0,0) (4,0) P1 Example (Cont…) Max Z= 3 P1 + 5 P2 s.t. P1 < 4 P2 < 6 3 P1 + 2 P2 < 18 P1, P2 >0 P2 (0,6) (2,6) (4,3) (6,0) (0,0) (4,0) P1 Example (Cont…) P2 (0,6) E (2,6) D C A (0,0) (4,3) (6,0) B (4,0) P1 Example (Cont…) Objective Function : Max Z= 3 P1 + 5 P2 Corner Points A – (0,0) B – (4,0) C – (4,3) D – (2,6) E – (0,6) Optimal Point : (2,6) Optimal Value : 36 Value of Z 0 12 27 36 30 Example Min z = 5x1 + 2x2 s.t. 2x1 + 5x2 > 10 4x1 - x2 > 12 x1 + x2 > 4 x 1, x 2 > 0 Example Min z = 5x1 + 2x2 s.t. 2x1 + 5x2 > 10 4x1 - x2 > 12 x1 + x2 > 4 x1, x2 > 0 x2 5 4x1 - x2 > 12 x1 + x2 > 4 4 3 2x1 + 5x2 > 10 2 1 1 2 3 4 5 6 x1 Example (Cont…) Min z = 5x1 + 2x2 s.t. 2x1 + 5x2 > 10 4x1 - x2 > 12 x1 + x2 > 4 x1, x2 > 0 x2 5 Feasible Region 4 This is the case of ‘Unbounded Feasible Region’. 3 2 A (35/11 , 8/11) 1 B (5,0) 1 2 3 4 5 6 x1 Electrical Engineering Techniques college 2021/2022 Example: - by using the (Graphical method) find the optimum solution of X1, X2. Max Z=6X1+4X2 Sub in to X1+3X2≤2 2.5 4X1+2X2≤5 X1,X2≥0 Solution: 1- In Eq . at X1=0 at X2=0 B(0,0.667) 0.667 X1+3X2=2 X2=0.667 (0,0.667) X1=2 (2,0) feasible regin 2- In Eq. at X1=0 at X2=0 4X1+X2=5 X2=2.5 (0,2.5) X1= 1.25 ( 1.25,0) A(0,0 ) D 1.25 2 c(1.25,0) to find point D ( X1+3X2=2)*4 4 X1+2X2=5 (1) (2) +4 X1+12X2= 8 -4X1 - 2 X2 = -5 X2=0.3 point A B C D sub in any eq 1or 2 X1=1.1 D=(1.1,0.3) X1 X2 Z=6X1+4X2 0 0 Z=0 0 0.667 Z=2.668 1.25 0 Z=7.5 1.1 0.3 Z=7.8 optimum solution in point D LINEAR PROGRAMMING PROBLEM Linear : form meant a mathematical expression of the type a1x1 + a2x2 + ……….+ anxn where a1, a2, ….., an are constants, and x1, x2, ………, xn are variables. Programming : refers to the process of determining a particular program or plan of action. Linear Programming Problem(LPP): Technique for optimizing(maximizing/minimizing) a linear function of variables called the ‘OBJECTIVE FUNCTION’ subject to a set of linear equations and/or inequalities called the ‘CONSTRAINTS’ or ‘RESTRICTIONS’. FORMULATION OF LP PROBLEMS LP Model Formulation Objective function a linear relationship reflecting the objective of an operation most frequent objective is to maximize profit or to minimize cost. Decision variables an unknown quantity representing a decision that needs to be made. It is the quantity the model needs to determine Constraint a linear relationship representing a restriction on decision making Steps in Formulating the LP Problems 1. 2. 3. 4. 5. Define the objective. (min or max) Define the decision variables. Write the mathematical function for the objective. Write the constraints. Constraints can be in <, =, or > form. Example Two products: Chairs and Tables Decision: How many of each to make this month? Objective: Maximize profit Data Profit Contribution Tables Chairs (per table) (per chair) $7 $5 carpentry 3 hrs 4 hrs Hours Available 2400 Painting 2 hrs 1 hr 1000 Other Limitations: • Make no more than 450 chairs • Make at least 100 tables Solution Decision Variables: T = Num. of tables to make C = Num. of chairs to make Objective Function: Maximize Profit Maximize $7 T + $5 C Constraints Have 2400 hours of carpentry time available 3 T + 4 C < 2400 (hours) Have 1000 hours of painting time available 2 T + 1 C < 1000 (hours) More Constraints: Make no more than 450 chairs C < 450 Make at least 100 tables T > 100 Non negativity: Cannot make a negative number of chairs or tables T>0 C>0 Model Max 7T + 5C Subject to the constraints: 3T + 4C < 2400 2T + 1C < 1000 C < 450 T > 100 T, C > 0 General Formulation of LPP Max/min z = c1x1 + c2x2 + ... + cnxn subject to: a11x1 + a12x2 + ... + a1nxn (≤, =, ≥) b1 a21x1 + a22x2 + ... + a2nxn (≤, =, ≥) b2 : am1x1 + am2x2 + ... + amnxn (≤, =, ≥) bm x1 ≥ 0, x2 ≥ 0,…….xj ≥ 0,……., xn ≥ 0. xj = decision variables bi = constraint levels cj = objective function coefficients aij = constraint coefficients Example Cycle Trends is introducing two new lightweight bicycle frames, the Deluxe and the Professional, to be made from aluminum and steel alloys. The anticipated unit profits are $10 for the Deluxe and $15 for the Professional. The number of pounds of each alloy needed per frame is summarized on the next slide. A supplier delivers 100 pounds of the aluminum alloy and 80 pounds of the steel alloy weekly. How many Deluxe and Professional frames should Cycle Trends produce each week? Example Pounds of each alloy needed per frame Deluxe Professional Aluminum Alloy 2 4 Steel Alloy 3 2 Solution Define the objective Maximize total weekly profit Define the decision variables x1 = number of Deluxe frames produced weekly x2 = number of Professional frames produced weekly Solution Max Z = 10x1 + 15x2 Subject To 2x1 + 4x2 < 100 3x1 + 2x2 < 80 x1 , x2 > 0 Example A firm manufactures 3 products A, B and C. The profits are Rs.3, Rs.2, and Rs.4 respectively. The firm has 2 machines and below is the required processing time in minutes for each machine on each product. Product A Machines B C G 4 3 5 H 2 2 4 Machine G and H have 2000 and 2500 machine-minutes respectively. The firm must manufacture 100 A’s, 200 B’s and 50 C’s, but not more than 150 A’s. Set up an LP problem to maximize profit. Solution Define the objective Maximize profit Define the decision variables x1 = number of products of type A x2 = number of products of type B x3 = number of products of type C Solution Max Z = 3x1 + 2x2 + 4x3 Subject To 4x1 + 3x2 + 5x3 ≤ 2000 2x1 + 2x2 + 4x3 ≤ 2500 100 ≤ x1 ≤ 150 x2 ≥ 200 x3 ≥ 50 x1, x2, x3 ≥ 0 Example The Sureset Concrete Company produces concrete. Two ingredients in concrete are sand (costs $6 per ton) and gravel (costs $8 per ton). Sand and gravel together must make up exactly 75% of the weight of the concrete. Also, no more than 40% of the concrete can be sand and at least 30% of the concrete be gravel. Each day 2000 tons of concrete are produced. To minimize costs, how many tons of gravel and sand should be purchased each day? Solution Define the objective Minimize daily costs Define the decision variables x1 = tons of sand purchased x2 = tons of gravel purchased Cont… Min Z = 6x1 + 8x2 Subject To x1 + x2 = 1500 x1 < 800 x2 > 600 x1 , x2 > 0 Electrical Engineering Techniques college 2021/2022 Solve problem of LP by using (formulation, graphical method, and simplex method) EX: - 1- you wish to produce two products i) ii) Walkman Am/Fm cassette. Watch Tv. 2- W.m takes 4 hours of electronic works and 2 hours assembly. 3- W.T takes 3 hours of electronic works and 1 hours assembly. 4- There are 240 hours of electronic works time and 100 hours of assembly time available. 5-profit on a W.m 7$ and on a T.v 5$? Find the max profit Sol: - Formulation of Lp Max Z=7X1+5X2 Sub in to 4X1+3X2≤240 2X1+X2≤100 X1,X2≥0 Electrical Engineering Techniques college 2021/2022 Graphical method Max Z=7X1+5X2 nSub to 4X1+3X2≤240 100 2X1+X2≤100 X1,X2≥0 1- B(0,80) In Eq . at X1=0 at X2=0 80 4 X1+3X2=240 X2= 80 (0,80) X1= 60 (60 ,0) feasible regin 2- In Eq. at X1=0 at X2=0 2X1+1X2=100 X2=100 (0,100) X1=50 (50,0) D 50 60 c( 50,0) to find point D 4 X1+3X2=240 ( 2X1+ X2=100)*2 (1) (2) +4 X1+3X2= 240 -4X1 - 2 X2 = -200 X2=40 sub in any eq 1or 2 X1=30 D=(30,40) point X1 X2 Z=7X1+5X2 A 0 0 Z=0 B 0 80 Z=400 C 50 0 Z=350 D 30 40 Z= 410 optimum solution in point D Z=410,x1=30,x2=40 Electrical Engineering Techniques college 2021/2022 Simplex method Max Z=7X1+5X2 Sub in to 4X1+3X2≤240 2X1+X2≤100 X1,X2≥0 Sol:Z-7X1-5X2=0 4X1+3X2+S1=240 2X1+X2+S2=100 X1,X2,s1,s2≥0 At X1=0,X2=0 Variable Z Z 1 S1 0 S2 0 S1=240 ,S2= 100 ,Z=0 X1 X2 S1 S2 -7 -5 0 0 4 3 1 0 2 1 0 1 Sol. 0 240 100 Ratio تهمل 60 50 variable Z X1 X2 S1 S2 Sol. Ratio Z 1 0 -1.5 0 3.5 350 تهمل S1 0 0 1 1 -2 40 40 X1 0 1 1/2 0 1/2 50 100 1-(-7*0)/2=1,0-(4*0)/2=0,-5-(-7*1)/2=-5+3=-1.5,3-(4*1)/2=3-2=1 0-(-7*0)/2=0,1-(4*0)/2=1,0-(-7*1)/2=3.5,0-(4*1)/2=-2,0-(7*100)/2=350,240-(4*100)/2=40 1-(-1.5*0)/1=1,0-(0*0.5)/1=0,0-(-1.5*1)/1=1.5,3.5-(-1.5*-2)/1=0.5 350-(-1.5*40)/1=410,1-(0*1/2)/1=1,0-(0.5*1) /1=-0.5,0.5-(-2*0.5)/1=0.5+1=1.5,50-(40*0.5)/1=30 variable Z X1 Z 1 0 X2 0 0 X1 0 1 Z=410,x1=30,x2=40 X2 0 1 0 S1 1.5 1 -0.5 S2 1/2 -2 1.5 Sol. 410 40 30 Electrical Engineering Techniques college 2021/2022 Engineering economics For Students of Fourth Stage Computer Department Department of computer engineering Electrical Engineering Techniques college 2021/2022 Engineering economics Engineering economics: - is branch of economics used by engineering to optimize their designs and construction projects. The following symbol and definitions P: - principle, a sum of money invested in initial year, or The present sum of money. i :- interest rate per of unit of time expressed as a decimal ex:- 5% = 0.05 n:- time , the number of units of times over which inters Accumulates. Electrical Engineering Techniques college 2021/2022 I: - simple interest F: - compound amount, a sum of money at end of n units at interest i . Simple interest Simple interest (I) = p i n Example:- an amount of 2500$ is deposit in a bank offering 5% simple interest per annum what is the interest at the end of the first year? Solution:P= 2500$ i=0.05 n= 1 Simple interest (I ) = p i n = 2500 * 0.05 * 1 = 125 $ Electrical Engineering Techniques college 2021/2022 Compound interest F= p(1+i)n P= f/ (1+i)n F=P(1+ )nm if interest i compound m times per period n Where m= 2 if compound semiannually m=4 if compound quarterly m= 12 if compound monthly m= 365 if compound daily Example1:- if you deposit 4000$ into an account paying 6% annual interest compound quarterly how much will be in the account after 5 years? Electrical Engineering Techniques college 2021/2022 Solution:P= 4000$ i=0.06 n= 5 m=4 F=p (1+ )nm = 4000( 1+0.06/4)(5)(4) F= 5387.42$ in the account Example2:- if you deposit 1000$ into an account paying 12% annual interest compound annually how much will be in the account after 4 years? Solution:P=1000$ F=p(1+i)n F=1000(1+0.012)4 F=1573.5$ i=12% n=4 years Electrical Engineering Techniques college 2021/2022 EX3:- A business man need to have 100,000$ in 5 years .How much must be put into his account in the bank ,10% annual interest assuming compound interest. Solution:F=100,000$ i=10% n=5 year F=p (1+i)n 100,000=p (1+0.1)5 p=62092.13$ EX4:-what the interest rate a compound semiannually will have to be earned in order for 500$ to amount to 1104 $ in ten years? Solution:P= 500$ i=? F=p (1+ )nm ( )1/nm = (1+ )nm/nm ( )1/nm= (1+ ) n= 10 m=2 F=1104$ Electrical Engineering Techniques college 2021/2022 )1/nm -1= i/m ( ( )1/20 -1= i/2 i=0.0808, i=8.08% Electrical Engineering Techniques college 2021/2022 HW HW 1:- if you deposit 8000$ into an account paying 9% annual interest compound semiannually how much will be in the account after 7 years? HW 2:- an amount of 3000$ is deposit in a bank offering 8% simple interest per annum what is the interest for the 5year? Electrical Engineering Techniques college 2021/2022 Electrical Engineering Techniques college 2021/2022 Layouts For Students of Fourth Stage Computer Department Department of computer Engineering Electrical Engineering Techniques college 2021/2022 Electrical Engineering Techniques college 2021/2022 Electrical Engineering Techniques college 2021/2022 Electrical Engineering Techniques college 2021/2022 Inventory For Students of Fourth Stage Computer Department Department of computer Engineering Electrical Engineering Techniques college 2021/2022 By the end of this topic, you should be able to: 1. Explain the importance of inventory control; 2. Compute the EOQ to determine how much to order 3. Compute the ROP in determining ► INTRODUCTION Inventory means any stored resource that is used to satisfy a current or a future need; for example, the raw materials and finished goods. Therefore the inventory control is crucial for every company. Reducing on-hand inventory level means reducing costs and thus increases the cash flow. On the other hand frequent stock outs may dissatisfy the customers. Thus a company must make a balance between low and high inventory levels. The major factor to be considered in achieving this balance is the cost minimization. INVENTORY DECISIONS There are two fundamental decisions that we have to make when controlling inventory: 1. How much to order or produce? 2. When to order? The major objective in controlling inventory is to minimize the total inventory costs which include: 1. Cost of the items (purchase cost or material cost) (Cp):- : it is usually the purchase price of the item under consideration. If unit cost is related with the purchase quantity, it is called as Electrical Engineering Techniques college 2021/2022 discount price. 2. Cost of ordering (Co):- This includes the cost of order preparation, tender placement, cost of postages, telephone costs, receiving costs, set up cost etc. 3. Cost of carrying or holding inventory (Ch):- This represents the cost of maintaining inventories in the plant. It includes the cost of insurance, security, warehouse rent, taxes, interest on capital engaged, spoilage, breakage etc. 4. Cost of stock outs. Or Shortage costs (Cs): This represents the cost of loss of demand due to shortage in supplies. This includes cost of loss of profit, loss of customer, loss of goodwill, penalty etc. Economic order quantity (EOQ) with no shortage This is the basic model in achieving an optimal ordering quantity which Minimizes the total inventory costs. However there are some assumptions to be upheld:1- Demand is deterministic and occurs at constant rate. 2- The unit purchase cost does not depend on the size of the order. In other words the model does not permit quantity discount. 3 ■ the lead time for each order is zero. Each order arrives as soon as it is placed. No shortages are allowed. That is all demands must be met on time; a negative inventory is not allowed either. Electrical Engineering Techniques college 2021/2022 Fig ure 1: Inv ent ory usage over time in a simple model The following mathematical equations √ Where:Annual Demand = D Ordering cost per order = Co Holding or carrying cost per unit per year = Ch Electrical Engineering Techniques college 2021/2022 √ Electrical Engineering Techniques college 2021/2022 Example (1): suppose the demand for a product is 6000 unit per year and the items are withdrawn uniformly. The order cost is S1000. The inventory holding cost is $2 per item per year. Assuming shortages are not allowed, find: (1) (2) (3) (4) The economic order quantity. The number of ordering during the year (order frequency). The interval between two orders (time between orders). The annual cost. Answer:√ 1- √ =2449.48≈2449 unit 2- orders 3- year 4- √ √ =4898.97$ Electrical Engineering Techniques college 2021/2022 Example (2): Suppose that the demand for a product is 2000 per year, and the items are withdrawn uniformly. The order cost is $150 and the inventory holding cost is $0.5 per item per month. Assuming shortages are not allowed, find: (1) (2) (3) (4) Tne economic order quantity. The number of ordering during the year ( order frequency). The interval between two orders (time between orders ), The annual cost. Answer:√ 1- √ =316.227≈316 unit 2- orders 3- 4- year √ √ =3600000$ Electrical Engineering Techniques college 2021/2022 Economic order quantity (EOQ) with shortage; The following mathematical equations ( )2 ( ) Electrical Engineering Techniques college 2021/2022 Electrical Engineering Techniques college 2021/2022 Example (3): Suppose that the demand for a product is 4000 per year, and the items are withdrawn uniformly. The order cost is $250 and the inventory holding cost is $5 per item per year. If shortages cost $10 per item per year, find: (1) The economic order quantity. (2) Maximum inventory. (3) Shortage allowable quantity. (2) The number of ordering during the year ( order frequency). (3) The interval between two orders (time between orders ). (4) The annual cost. Answer:- √ 1- √ =774.597 775 unit 2- = =516.6≈517 unit 3- =258.3 ≈ 258 unit Electrical Engineering Techniques college 2021/2022 4= =5.16≈ 5 order 5= =0.193 year 6- = 2581$ ( )2 ( )2 ( ) ( ) Electrical Engineering Techniques college 2021/2022 Re-order Level or Ordering Point or Ordering Level This is that level of materials at which a new order for supply of materials is to be placed. In other words, at this level a purchase requisition is made out. This level is fixed somewhere between maximum and minimum levels. Order points are based on usage during time necessary to requisition order, and receive materials, plus an allowance for protection against stock out. The order point is reached when inventory on hand and quantities due in are equal to the lead time usage quantity plus the safety stock quantity. According to Fangruo Chen, the ROP quantity reflects the level of inventory that triggers the placement of an order for additional units. Whereas, the quantity associated with safety stock protects the company from stock outs or backorders. Safety stock is also known as a "buffer” In determining the reorder point the following three factors need to be at hand: 1. Demand - Quantity of inventory used or sold each day 2. Lead Time - Time (in days) it takes for an order to arrive when an order is placed. 3. Safety Stock - The quantity of inventory kept on hand in case there is an unpredictable event like delays in lead time or unexpected demand. Formula of Re-order Level or Ordering Point: The following two formulas are used for the calculation of reorder level or point. Ordering point or re-order level = Maximum daily or weekly or monthly usage x Lead time The above formula is used when usage and lead time are known with certainty; therefore, no safety stock is provided - Electrical Engineering Techniques college 2021/2022 When safety stock is provided then the following formula will be applicable: Ordering point or re-order level = Maximum daily or weekly or monthly usage x Lead time + Safety stock Examples: Example 1: Minimum daily requirement Time required to receive emergency supplies Average daily requirement Minimum daily requirement Time required for refresh supplies 800 units 4 days 700 units 600 units One month (30 days) Calculate ordering point or re-order level Calcul ation: Ordering point = Ordering point or re-order level = Maximum daily or weekly or monthly usage x Lead time = 800 x 30 = 24,000 units - Electrical Engineering Techniques college 2021/2022 Example 2: Two types of materials are used as Minimum usage 20 units per week each 40 units per Maximum usage week each 60 units per week each Normal usage Re-order period time Material A: Material B or Lead 3 to 5 weeks 2 to 4 weeks Calculate re order point for two types of materials. Calculation: Ordering point or re-order level = Maximum daily or weekly or monthly usage x Maximum re-order period A: 60 x 5 = 300 units B:60x 4=240 units - Electrical Engineering Techniques college 2021/2022 - Electrical Engineering Techniques college 2021/2022 ( Productivity ) Productivity is commonly defined as a ratio between the output volume and the volume of inputs. In other words, it measures how efficiently production inputs, such as labor and capital, are being used in an economy to produce a given level of output. Productivity= SAMPLE PROBLEMS FOR PRODUCTIVITY Example 1 A company that processes fruits and vegetables is able to produce 400 cases of canned peaches in one half hour with four workers. What is the labor productivity? Solution: Labor productivity = Quality Produced / Labors Hours = 400 cases/ (4 workers x 1/2 hours / workers) = 200 cases per labor hour Example 2 A wrapping paper company produced 2,000 rolls of paper one day. Standard price is $ 1/roll. Labor cost was $ 160, material cost was $ 50, and overhead was $ 320. Determine the multifactor productivity. Solution: Multifactor productivity = Quality produced at standard price/ (Labor cost + Material cost + Overhead) = 2,000 rolls x $ 1/ ($160+ $ 50 + $320) Electrical Engineering Techniques college 2021/2022 = 3.77 rolls output per dollars Example 3 a) Find the productivity if four workers installed 720 square yards of carpeting in Eight hours. b) Compute for the productivity of a machine which produced 68 usable pieces in two Hours. Solution: a) Productivity = yards of carpeting install / Labors Hours worked = 720 square yard / (4 workers x8 hours / worker) = 720 yards / 32 Hours = 22.5 yards/ hours b) Productivity = Usable Pieces / Production Time = 68 usable pieces / 2 hrs. = 34 pieces/ hours Example # 4 Determine the multifactor productivity for the combined input of the labor and the machine time using the following: Input: Labor: $ 1,000 Materials: $ 520 Overheads: $ 2,000 Keep in mind the Production is 1760 unit Solution: Multifactor Productivity = Output / (Labor + Materials + Overheads) = 1,760 Units / ($ 1,000 + $ 520 + $ 2,000) = 0.50 units/$ Electrical Engineering Techniques college 2021/2022 Solve the Following Problems Problem Company has a staff of 4, each working 8 hours per day (for a payroll cost of $ 640 / day) and overhead expenses of $ 400 / day. Company Processes and closes on 8 outputs each day. The company recently purchased a new system that will allow the processing of 14 outputs per day. Although the staff, their works hours, and pay will be same, the overheads expenses are now $ 800 per day. Solution: Labor productivity with the old system: = 8 output per day/ 32 labor hours = 0.25 output per labor hour Labor productivity with the new system: =14 output per day/ 32 labor hours = 0.44 output per labor hours Multifactor productivity with the old system: =8 output per day / (640 + 400) = 0.0077 output per dollars Multifactor productivity with the new system: =14 output per day / (640 + 800) = 0.0097 output per dollars Problem A company producer of an apple boxes sold to growers has been able, with his current equipment, to produces 240 boxes per 100 logs. He currently purchases 100 logs per day, and each logs required 3 labor hours to process. He believes that he can hire a professional buyer who can buy a better quality log at the same cost. If this is the case, he increases his production to 260 boxes per 100 logs. His labor hours Electrical Engineering Techniques college 2021/2022 will increase by 8 hours per day. What will be the impact on productivity (measured in crates per labor –hour) if the buyers is hired? What is the Growth in productivity in this case? Solution: a) Current labor productivity = 240 boxes / 100 logs (3 hours pert log) = 240/ 300 = 0.8 boxes per labor hour b) Labor productivity with buyer = 260 boxes / (100 logs (3 hours per logs) + 8 hours ) = 260 / 308 = 0.844 boxes per labor hours c) Growth = (0.844 – 0.8)/0.8 x100 = Problem Calculate the productivity for the following operations: a) Three employees processed 600 insurance policies last week. They 8 hours per day, 5 days per week. b) A team of workers made 400 units of product, which is valued by its standard cost of $10 each (before markups for other expenses and profit). That accounting department reported that for this job the actual cost were $ 400 per labor, $1000 for materials and $300 for overhead: Solution: a) Labor productivity = Policies processed/ Employee hours = 600 policies /3 (40) = 5 policies per hours b) Multifactor productivity = Quality at standard cost Labor + Materials + Overheads = 400units ($10/units)/( $400 + $1000 + $ 300) = $4000/$1700 =2.35 Problem Electrical Engineering Techniques college 2021/2022 Student tuition at Boering University is $ 100 per semester credit hours. The states supplement school revenue by matching student tuition, 100dollars. Average class size for typical three credit course is 50 students. Labor costs are $4000 per class, material costs are $20 per student, and overhead cost are $25,000 per class. Find: a) What is the multifactor productivity ratio? b) If instructors work an average, what is the labor productivity ratio? (Keep in mind that professor delivering the lecture work 14 hours per week the semester last for 16 weeks) Solution: a) Value of Output = (50 student) x (3 credit hours) x ($ 100 tuition + $ 100 state support) Class student credit hours = $ 30,000 per class Value of input = Labor + Materials + Overheads = $ 4000 + ($20 per student x 50 students) + $25,000 Class = $ 30,000 per class Multifactor productivity = Output/ Input = $ 30,000 per class /$ 30,000 per class = 1.00 b) Labor productivity is the ratio of the value of output to the labor hours. The value of output is the same as in part (a), or $ 30,000 per class, so Labor hours of input = 14 hours x 16 week = 224hours per class Labor productivity = Output/ Input = $ 30,000 per class/ 224 hours per class = $ 133.93 per hours Electrical Engineering Techniques college 2021/2022 Electrical Engineering Techniques college 2021/2022 Electrical Engineering Techniques college 2021/2022 Electrical Engineering Techniques college 2021/2022 Quality control is a process that measures output relative to standard, and acts when output doesn't meet standards. The purpose of quality control is to assure that processes are performing in an acceptable manner. Companies accomplish quality control by monitoring process output using statistical techniques This approach places an emphasis on three aspects 1 Elements such as controls, job management, defined and well managed processes, performance and integrity criteria, and identification of records Competence, qualifications 2 3 Soft such elements, as such knowledge, as skills, personnel, experience, integrity, and confidence, organizational culture, motivation, team spirit, and quality relationships. Types of control charts There are four types of control charts; two for variables, and two for attributes Electrical Engineering Techniques college 2021/2022 Attribute: counted data (e.g., number of defective items in a sample, the number of calls per day) Variable: measured data, usually on a continuous scale (e g., amount of time needed to complete a task, length, width, weight, diameter of a part) Variables Control Charts Mean control charts *Used to monitor the central tendency of a process. *X-bar charts Range control charts *Used to monitor the process dispersion *R charts Control Chart for Attributes Control charts for attributes are used when the process characteristic is counted rather than measured. Two types are available: • P-Chart - Control chart used to monitor the proportion of defectives in a process • C-Chart - Control chart used to monitor the number of defects per unit Electrical Engineering Techniques college 2021/2022 Electrical Engineering Techniques college 2021/2022 Electrical Engineering Techniques college 2021/2022 Electrical Engineering Techniques college 2021/2022 Electrical Engineering Techniques college 2021/2022 P-Chart Example 4:- an inspection counted the number of defective monthly billing statements of a company telephone in each of 20 samples. Using The following information, construct a control chart that will describe 99.74 percent of the chance variation in the process when the process Is in control. Each sample contained 100 statements.(z=3) Sample 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 Number of defectives 4 10 12 3 9 11 10 22 13 10 8 12 9 10 21 10 8 Electrical Engineering Techniques college 2021/2022 18 19 20 12 10 16 ∑220 Solution:- ̅ ( ̂ √ ̅( ̅) Control limit are ̅ ̅ ( ̂) ( ( ̂) ( ) ) ) Electrical Engineering Techniques college 2021/2022 C-chart Example 4:- roll of coiled wire are monitored using c-chart eighteen rolls have been examined and the number of defects per roll has been recorded in the Following table. Is the process in control? Using three Standard deviation control limits.z=3 Sample 1 2 3 4 5 6 7 8 9 10 11 12 13 Number of defects 3 2 4 5 1 2 4 1 2 1 3 4 2 Electrical Engineering Techniques college 2021/2022 14 15 16 17 18 4 2 1 3 1 ∑45 ̅ ̅ √̅ √ =7.24 ̅ =-2.24 √̅ √ Electrical Engineering Techniques college 2021/2022 Electrical Engineering Techniques college 2021/2022 Employee Relationship Management Employees are the major assets of an organization. It is essential that the employees perform together as a collective unit and contribute equally towards the realization of a common goal. No task can be accomplished if the individuals are engaged in constant conflicts and misunderstandings. It has been observed that targets are achieved at a much faster rate if the employees work together and share a warm relationship with each other. .Employees must be comfortable with each other to deliver their best and enjoy their work What is employee relationship management? Employee relationship management refers to managing the relation between the various employees in an organization. The relationship can be between employee and the employer .as well as between employees at the same level What is Management? Management is nothing but a technique which brings people together on a common platform and guides them so that they achieve their desired targets without fighting with each other. In a layman’s language, management is nothing but managing things effectively so that tasks are accomplished without any hassles and confusions. Management is required .everywhere Every individual goes for shopping. The moment you enter in an outlet, a sales person would come to you and assist you in your shopping. He would try his level best to convince you and guide you in selecting an outfit according to your taste as well as budget. The moment you finalize something, you automatically would be directed to the billing section for the monetary transactions. Your shopping basket in no time would reach the packing area where the officials would nicely put the outfits in a smart carry bag flaunting the logo of the store. Finally there would be a supervisor who would recheck your bill and thank you for your .valuable time How do you think such a smooth coordination is possible? Not a single moment, there was any confusion. All this is possible through management. Every thing was well managed and organized effectively to avoid confusions and meet the ultimate objective of the store ie .selling the product as well as making the customer happy Electrical Engineering Techniques college 2021/2022 Employee relationship management is an art which effectively monitors and manages the relation between individuals either of the same team or from different teams. Employee relationship management activity helps in strengthening the bond among the employees .and ensures that each one is contented and enjoys a healthy relation with each other Employee relationship management includes various activities undertaken by the superiors or the management to develop a healthy relation among the employees and extract the best .out of each team member Simplex Method When decision variables are more than 2, we always use Simplex Method Slack Variable: Variable added to a constraint to convert it to an equation (=). A slack variable represents unused resources A slack variable contributes nothing to the objective function value. Surplus Variable: Variable subtracted from a constraint to convert it to an equation (=). A surplus variable represents an excess above a constraint requirement level. Surplus variables contribute nothing to the calculated value of the objective function. Cont…. Basic Solution(BS) : This solution is obtained by setting any n variables (among m+n variables) equal to zero and solving for remaining m variables, provided the determinant of the coefficients of these variables is nonzero. Such m variables are called basic variables and remaining n zero valued variables are called non basic variables. Basic Feasible Solution(BFS) : It is a basic solution which also satisfies the non negativity restrictions. Cont….. BFS are of two types: Degenerate BFS: If one or more basic variables are zero. Non-Degenerate BFS: All basic variables are non-zero. Optimal BFS: BFS which optimizes the objective function. Example Max. Z = 13x1+11x2 Subject to constraints: 4x1+5x2 < 1500 5x1+3x2 < 1575 x1+2x2 < 420 x1, x2 > 0 Solution : Step 1: Convert all the inequality constraints into equalities by the use of slack variables. Let S1, S2 , S3 be three slack variables. Introducing these slack variables into the inequality constraints and rewriting the objective function such that all variables are on the left-hand side of the equation. Model can rewritten as: Z - 13x1 -11x2 = 0 Subject to constraints: 4x1+5x2 + S1 = 1500 5x1+3x2 +S2= 1575 x1+2x2 +S3 = 420 x1, x2, S1, S2, S3 > 0 Cont… Step II: Find the Initial BFS. One Feasible solution that satisfies all the constraints is: x1= 0, x2= 0, S1= 1500, S2= 1575, S3= 420 and Z=0. Now, S1, S2, S3 are Basic variables. Step III: Set up an initial table as: Cont… Row NO. Basic Variable Coefficients of: Sol. Rati o Z x1 x2 S1 S2 S3 A1 Z 1 -13 -11 0 0 0 0 B1 S1 0 4 5 1 0 0 1500 375 C1 S2 0 5 3 0 1 0 1575 315 D1 S3 0 1 2 0 0 1 420 420 Step IV: a) Choose the most negative number from row A1(i.e Z row). Therefore, x1 is a entering variable. b) Calculate Ratio = Sol col. / x1 col. (x1 > 0) c) Choose minimum Ratio. That variable(i.e S2) is a departing variable. Cont…. Step V: x1 becomes basic variable and S2 becomes non basic variable. New table is: Row NO. Basic Varia ble Coefficients of: Sol. Ratio Z x1 x2 S1 S2 S3 A1 Z 1 0 -16/5 0 13/5 0 4095 B1 S1 0 0 13/5 1 -4/5 0 240 92.3 C1 x1 0 1 3/5 0 1/5 0 315 525 D1 S3 0 0 7/5 0 -1/5 1 105 75 Cont… Next Table is : Row NO. Basic Variab Z le Coefficients of: Sol. x1 x2 S1 S2 S3 A1 Z 1 0 0 0 15/7 16/7 4335 B1 S1 0 0 0 1 -3/7 -13/7 45 C1 x1 0 1 0 0 2/7 -3/7 270 D1 x2 0 0 1 0 -1/7 5/7 75 Optimal Solution is : x1= 270, x2= 75, Z= 4335 Example Max. Z = 3x1+5x2+4x3 Subject to constraints: 2x1+3x2 < 8 2x2+5x3 < 10 3x1+2x2+4x3 < 15 x1, x2, x3 > 0 Cont… Let S1, S2, S3 be the three slack variables. Modified form is: Z - 3x1-5x2-4x3 =0 2x1+3x2 +S1= 8 2x2+5x3 +S2= 10 3x1+2x2+4x3+S3= 15 x 1 , x 2 , x 3 , S1 , S2 , S3 > 0 Initial BFS is : x1= 0, x2= 0, x3=0, S1= 8, S2= 10, S3= 15 and Z=0. Cont… Basic Variable Z Coefficients of: Sol. Ratio x1 x2 x3 S1 S2 S3 Z 1 -3 -5 -4 0 0 0 0 S1 0 2 3 0 1 0 0 8 8/3 S2 0 0 2 5 0 1 0 10 5 S3 0 3 2 4 0 0 1 15 15/2 Therefore, x2 is the entering variable and S1 is the departing variable. Cont… Basic Variable Z Coefficients of: Sol. Ratio x1 x2 x3 S1 S2 S3 Z 1 1/3 0 -4 5/3 0 0 40/3 x2 0 2/3 1 0 1/3 0 0 8/3 - S2 0 -4/3 0 5 -2/3 1 0 14/3 14/15 S3 0 5/3 0 4 -2/3 0 1 29/3 29/12 Therefore, x3 is the entering variable and S2 is the departing variable. Cont… Basic Variable Z Coefficients of: Sol. x1 x2 x3 S1 Z 1 -11/15 0 0 17/15 4/5 0 256/15 x2 0 2/3 1 0 1/3 0 8/3 4 x3 0 -4/15 0 1 -2/15 1/5 0 14/15 - S3 0 41/15 0 0 2/15 1 89/15 89/41 S2 0 -4/5 Ratio S3 Therefore, x1 is the entering variable and S3 is the departing variable. Cont… Basic Variable Z Coefficients of: Sol. x1 x2 x3 S1 S2 S3 Z 1 0 0 0 45/41 24/41 11/41 765/41 x2 0 0 1 0 15/41 8/41 -10/41 50/41 x3 0 0 0 1 -6/41 5/41 4/41 62/41 x1 0 1 0 0 -2/41 -12/41 15/41 89/41 Optimal Solution is : x1= 89/41, x2= 50/41, x3=62/41, Z= 765/41 Example Min.. Z = x1 - 3x2 + 2x3 Subject to constraints: 3x1 - x2 + 3x3 < 7 -2x1 + 4x2 < 12 -4x1 + 3x2 + 8x3 < 10 x1, x2, x3 > 0 Cont… Convert the problem into maximization problem Max.. Z’ = -x1 + 3x2 - 2x3 where Z’= -Z Subject to constraints: 3x1 - x2 + 3x3 < 7 -2x1 + 4x2 < 12 -4x1 + 3x2 + 8x3 < 10 x1, x2, x3 > 0 Cont… Let S1, S2 and S3 be three slack variables. Modified form is: Z’ + x1 - 3x2 + 2x3 = 0 3x1 - x2 + 3x3 +S1 = 7 -2x1 + 4x2 + S2 = 12 -4x1 + 3x2 + 8x3 +S3 = 10 x1, x2, x3 > 0 Initial BFS is : x1= 0, x2= 0, x3=0, S1= 7, S2= 12, S3 = 10 and Z=0. Cont… Basic Variable Z’ Coefficients of: Sol. Ratio x1 x2 x3 S1 S2 S3 Z’ 1 1 -3 2 0 0 0 0 S1 0 3 -1 3 1 0 0 7 - S2 0 -2 4 0 0 1 0 12 3 S3 0 -4 3 8 0 0 1 10 10/3 Therefore, x2 is the entering variable and S2 is the departing variable. Cont… Basic Variable Z’ Coefficients of: Sol. Ratio x1 x2 x3 S1 S2 S3 Z’ 1 -1/2 0 2 0 3/4 0 9 S1 0 5/2 0 3 1 1/4 0 10 4 x2 0 -1/2 1 0 0 1/4 0 3 - S3 0 -5/2 0 8 0 -3/4 1 1 - Therefore, x1 is the entering variable and S1 is the departing variable. Cont… Basic Variable Z’ Coefficients of: Sol. x1 x2 x3 S1 S2 S3 Z’ 1 0 0 13/5 1/5 8/10 0 11 x1 0 1 0 6/5 2/5 1/10 0 4 x2 0 0 1 3/5 1/5 3/10 0 5 S3 0 0 0 11 1 -1/2 1 11 Optimal Solution is : x1= 4, x2= 5, x3= 0, Z’ = 11 Z = -11 Example Max.. Z = 3x1 + 4x2 Subject to constraints: x1 - x2 < 1 -x1 + x2 < 2 x1, x2 > 0 Cont… Let S1 and S2 be two slack variables . Modified form is: Z -3x1 - 4x2 = 0 x1 - x2 +S1 = 1 -x1 + x2 +S2 = 2 x1 , x 2 , S1 , S2 > 0 Initial BFS is : x1= 0, x2= 0, S1= 1, S2= 2 and Z=0. Cont… Basic Variable Z Coefficients of: Sol. Ratio x1 x2 S1 S2 Z 1 -3 -4 0 0 0 S1 0 1 -1 1 0 1 - S2 0 -1 1 0 1 2 2 Therefore, x2 is the entering variable and S2 is the departing variable. Cont… Basic Variable Z Coefficients of: Sol. Ratio x1 x2 S1 S2 Z 1 -7 0 0 4 8 S1 0 0 0 1 1 3 - x2 0 -1 1 0 1 2 - x1 is the entering variable, but as in x1 column every no. is less than equal to zero, ratio cannot be calculated. Therefore given problem is having a unbounded solution. The Break-Even Point The break-even point is that quantity of output where total revenues equals total costs : that is, where the operating income is zero. Abbreviations COST-VOLUME-PROFIT ANALYSIS USP = Unit selling price UVC = Unit variable costs UCM = Unit contribution margin (USP-UVC) CM% = Contribution margin percentage (UCM/USP) FC = Fixed costs Q = Quantity of output units sold (and manufactured) OI = Operating Income TOI = Target operating income TNI = Target net income CHAPTER 3 COST-VOLUME-PROFIT ANALYSIS Objective 3 methods for determining break- even point Cost Accounting: A managerial emphasis 1. Equation method: Revenues – Variable costs – Fixed Costs = Operating Income (USP*Q) – (UVC*Q) – FC = OI Provides the most general and easy-to-remember approach Example: Variable cost=120$/unit Sell price =200$/unit Fixed cost=2000$ $200Q - $120Q -$2000= $0 Q= $2000/$80 Q= 25 units $80Q= $2000 CHAPTER 3 COST-VOLUME-PROFIT ANALYSIS 2.Contribution margin method: It uses the concept of contribution margin to rework the equation method. (USP*Q) – (UVC*Q) – FC = OI By rewriting, (USP – UVC) * Q = FC + OI UCM*Q = FC + OI Q = (FC +OI)/UCM At break-even, OI=0, therefore: Q = FC /UCM Break-even no. of units = Fixed costs/Unit contribution margin CHAPTER 3 COST-VOLUME-PROFIT ANALYSIS Objective 3 Cost Accounting: A managerial emphasis Substituting, Break-even no. of units = Fixed costs/Unit contribution margin Break-even no. of units = $2000/$80 per unit = 25 units Calculating break-even revenues, Break-even in revenue dollars = Break-even no. of units X USP = (FC*USP)/UCM = FC/(UCM/USP) Since, CM% = UCM/USP = $80/$200 = 40% = FC/CM% = $2000/40% Break-even in revenue dollars = $5000 TR Revenue and Costs Y 3. Graph method: Profits Break Even Point TC TVC TFC Loss 0 Q Output X Y Revenue and Costs TR Break Even Point Profits TC TFC Loss 0 Q Output Diagram of Break Even Point X CHAPTER 3 COST-VOLUME-PROFIT ANALYSIS Objective 3 Cost-Volume-Profit Graph for Do-All Software Operating Income area $12,000.00 Break-even point $10,000.00 Operating Income Cost Accounting: A managerial emphasis $14,000.00 $8,000.00 $6,000.00 Total revenues Total costs $4,000.00 $2,000.00 Operating Loss area $0.00 0 5 10 15 20 25 30 35 Units Sold 40 45 50 55 60 EXAMPLE • John sells a product for $10 and it cost $5 to produce (UVC) and has fixed cost (FC) of $25,000 per year • How much will he need to sell to break-even? • How much will he need to sell to make $1000? 1. Equation method: Revenues – Variable cost – Fixed cost = OI (USP x Q) – (UVC x Q) – FC = OI $10Q - $5Q – $25,000 = $ 0.00 $5Q = $25,000 Q = 5,000 What quantity demand will earn $1,000? $10Q - $5Q - $25,000 = $ 1,000 $5Q = $26,000 Q = 5,200 2.Contribution Margin Method (USP – UVC) x Q = FC + OI Q= FC + OI UMC Q= $25,000 + 0 $5 Q= 5,000 What quantity needs sold to make $1,000? Q = $25,000 + $1,000 $5 Q = 5,200 3.Graphical Method: Dollars 70,000 Total Cost 60,000 Line 50,000 40,000 30,000 20,000 Total Revenue Break-even point 10,000 Line 0 1000 2000 3000 4000 5000 6000 Quantity Graphical Method :Cont. Dollars 70,000 Total Cost 60,000 Line 50,000 40,000 30,000 20,000 Total Revenue Break-even point 10,000 Line 0 1000 2000 3000 4000 5000 6000 Quantity Break-even Analysis: Comparing different variables • Company XYZ has to choose between two machines to purchase. The selling price is $10 per unit. • Machine A: annual cost of $3000 with per unit cost (VC) of $5. • Machine B: annual cost of $8000 with per unit cost (VC) of $2. Break-even analysis: Comparative analysis Part 1 • Determine break-even point for Machine A and Machine B. • Where: V = FC SP - VC Break-even analysis: Part 1, Cont. Machine A: v = $3,000 $10 - $5 = 600 units Machine B: v = $8,000 $10 - $2 = 1000 units Part 1: Comparison • Compare the two results to determine minimum quantity sold. • Part 1 shows: – 600 units are the minimum. – Demand of 600 you would choose Machine A. Part 2: Comparison Finding point of indifference between Machine A and Machine B will give the quantity demand required to select Machine B over Machine A. Machine A FC + VC $3,000 + $5 Q $3Q Q = Machine B = FC + VC = $8,000 + $2Q = $5,000 = 1667 Part 2: Comparison Cont. • Knowing the point of indifference we will choose: • Machine A when quantity demanded is between 600 and 1667. • Machine B when quantity demanded exceeds 1667. Part 2: Comparison Graphically displayed Dollars 21,000 18,000 Machine A 15,000 12,000 9,000 Machine B 6,000 3,000 0 500 1000 1500 2000 2500 3000 Quantity Part 2: Comparison Graphically displayed Cont. Dollars 21,000 18,000 Machine A 15,000 12,000 9,000 Machine B 6,000 Point of indifference 3,000 0 500 1000 1500 2000 2500 3000 Quantity Exercise 1: • Company ABC sell widgets for $30 a unit. • Their fixed cost is$100,000 • Their variable cost is $10 per unit. • What is the break-even point using the basic algebraic approach? Exercise 1: Answer Revenues – Variable cost - Fixed cost = OI (USP x Q) – (UVC x Q) – FC $30Q - $10Q – $100,00 $20Q Q = = = = OI $ 0.00 $100,000 5,000 Exercise 2: • Company DEF has a choice of two machines to purchase. They both make the same product which sells for $10. • Machine A has FC of $5,000 and a per unit cost of $5. • Machine B has FC of $15,000 and a per unit cost of $1. • Under what conditions would you select Machine A? Exercise 2: Answer Step 1: Break-even analysis on both options. Machine A: v = $5,000 $10 - $5 = 1000 units Machine B: v = $15,000 $10 - $1 = 1667 units Exercise 2: Answer Cont. Machine A FC + VC $5,000 + $5 Q $4Q Q = Machine B = FC + VC = $15,000 + $1Q = $10,000 = 2500 • Machine A should be purchased if expected demand is between 1000 and 2500 units per year. Summary: • Break-even analysis can be an effective tool in determining the cost effectiveness of a product. • Required quantities to avoid loss. • Use as a comparison tool for making a decision.