MOS 3330 Course Overview
1. Introduction
2. Supply Chain Management
3. Inventory Management
4. Forecasting
5. Aggregate Planning
6. Material Requirements Planning
7. Enterprise Resource Planning
8. Process and Product Design
9. Just-In-Time Systems
10. Quality
11. Statistical Process Control
12. Total Quality Management
Test 1
Formula
Sheet
Formula
Sheet
Formula
Sheet
Formula
Sheet
Formula
Sheet
Formula
Sheet
MOS 3330: OM Introduction
Test 2
Final
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INTRODUCTION TO OPERATIONS MANAGEMENT
Learning Objectives:
1. What is Operations Management (OM)
2. Why study OM
3. Goods vs. services
4. Trends in OM
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1. What is Operations Management (OM)?
Organizational view
Manufacturing or Service Organization
Marketing
Sales
Advertising
Sales promotion
Market research
Operations
Facilities
Production
Inventory control
Quality assurance
Purchasing
Engineering
Finance
Credits
Disbursements
Funds management
Capital requirements
Support functions:
Human Resources, Information Technology, Administration
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Process view
Operations: Transformation of inputs into finished goods
and services
Inputs
Raw materials
Supplies
Employee skills
Facilities
Capital
Equipment
Transformation
Physical (ex. Manufacturing)
Locational (ex. Deliveries)
Exchange (ex. Retail)
Physiological (ex. Healthcare)
Psychological (ex. Entertainment)
Informational (ex. Education)
Outputs
Finished goods
Services
Operations Management: Planning, design, coordination
and execution of operations-related activities
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Strategic view
Market Analysis
Environmental Scan &
Internal Audit
Mission & Vision
Corporate Strategy
Future direction
Competitive priorities
Operations Strategy
Cost
Quality
Time
Flexibility
Low
High
Consistent
Fast
On-time
Customization
Volume
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2. Why Study OM?
At the core of all organizations
Interrelated with other areas’ activities
Contribution to the overall corporate strategy
25% of all Canadian jobs are in goods-producing sector
Operations managers manage:
Production/service
Technology
People
Projects
Strategy
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3. Goods vs. Services
Service is:
Usually intangible and “consumed” right after serving
High customer interaction
Often customized and cannot be stored for future use
Service, compared to producing goods, is more:
Labour intensive, knowledge based, difficult to automate,
difficult to measure service quality and productivity
Total productivity = Output / Input
In many cases, distinction is not clear-cut
For example, fast food, computer
Service as a distinguishing factor for a manufacturing firm
MOS 3330: OM Introduction
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MOS 3330: OM Introduction
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SUPPLY CHAIN MANAGEMENT
Learning Objectives:
1. Supply chains
2. Supply chain related subjects
3. Bullwhip effect
4. Supply chain strategies
5. Supplier relationships
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1. Introduction
Supply chain: A network of facilities, functions, and
activities involved in producing and delivering
products or services, from suppliers to customers
Supply chain management: (i) coordination of the
movement of goods through the supply chain, and
(ii) control of information such as sales data, sales
forecasts, promotions, and inventory levels
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1.1 Traditional View of Supply Chains
Manufacturers
Suppliers
Wholesalers
Distributors
Information Flow
Retailers
Goods Flow
Customers
Revenue Flow
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1.2 Network View of Supply Chains
Active
Ingredients
Pharmaceutical
products
Tablets
Capsules
Chemicals
Packaging
Formulation
Printed labels
& materials
Bottles, caps
Tier 1 suppliers
(e.g., for Packaging)
= direct suppliers
Primary
Packaging
Secondary
Packaging
Blank
labels
Tier 2 suppliers
(e.g., for Packaging)
= suppliers who supply
to tier 1 suppliers
Label
Manufacturer
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Distributor
Pharma.
products
Retail
Pharmacy
Pharma.
products
Customer
12
1.3 e-Supply Chains
Logistics
Data
Supply
Data
Customers
Customer
Data
Production
Data
Logistics
Providers
Suppliers
Contract
Manufacturers
Information Flow
Goods Flow
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2. Supply Chain Subjects
Logistics
Purchasing
Sourcing
Bullwhip effect
Sustainable
Other subjects (mention only)
Information management: accuracy, timing
Globalization: foreign business practices and regulations
e-Commerce
Radio Frequency Identification (RFID)
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2.1 Logistics
Shipping and delivery: transportation cost, mode, lead time,
traffic management
Highway flexibility
Rail or water high volume at low cost
Pipeline high volume at low cost
Air fast
Distribution management
Facility location (where/how many facilities?): proximity to
customers, business climate, quality of labour, infrastructure
Positioning of inventory (where/how many to hold?)
Third-party logistics (3PL)
Outsourcing freight consolidation and distribution activities
International business
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2.2 Purchasing
Ordering and receiving materials: materials of correct
quality, in correct quantity, at good price, and on time
Purchasing cycle:
1. Purchasing receives the requisition
2. Purchasing selects a supplier
3. Purchasing places the order with the vendor
4. Monitoring orders
5. Receiving orders
Interface with accounting, engineering, & legal teams
Develop a supplier base: select, evaluate & maintain
Sourcing
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2.3 Sourcing
Selecting suppliers
Price, quality, services, location, inventory policy, flexibility
Supplier selection strategies
Single Sourcing
Multiple Suppliers
- Quantity discount
- More responsive
- Frequent deliveries
- High quality
- Better relations
- Support just-in-time
- Competitive pricing
- Spreading risks
- Low dependence
- Volume flexibility
- Easier to test new supplier
- Not enough capacity
- Government regulations
- Order is too small
- High ordering cost
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3. Bullwhip Effect
Increasing distortion of information along the
supply chain
Customer demand gets distorted as information reaches
suppliers
Contributing factors
Batch ordering, high ordering cost, free return policy
Promotions, pricing that leads to forward buy
No visibility of end demand, inaccurate forecast
Long lead time, localized reaction
Mistrust, conflict of interest
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Bullwhip Effect
Source: Johnson & Pike (1999)
Grocery store order size
Distribution centre order size
Central warehouse order size
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3.1 Implications of the Bullwhip Effect
Loss of volume breaks
Higher freight costs
Higher raw material inventory
Raw material
expediting
Lower
revenues
Supplier
schedule
variability
Manufacturer
Schedule
changes
Productivity loss
Higher WIP Inventory
Customer
switching
Increased
safety stock
Retailer
Distributor
Poor
demand
planning
Higher finished goods
inventory &
warehousing costs
Stockouts
and late
orders
Poor service &
longer lead time
Small
Shipments &
Shipping b/w
Warehouses
Higher shipping
costs
Order of consequences
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3.2 Solutions to the Bullwhip Effect
Traditional “solution” = increase inventory
Modern approach
Examine the contributing factors
Improve the supply chain metrics
Understand the supply chain relationships:
interdependent, systemic and goal sharing
Improve coordination, communication & collaboration
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4. Supply Chain Strategies
Physical proximity
75% of Honda’s suppliers are located within 150 miles of its
Marysville plant in Ohio
Plant-direct shipping: from the manufacturer to retailer
Pampers to Wal-Mart, Dell Computer
Cross-docking: goods move from one loading dock to
another without being stored as an inventory
Wal-Mart distribution centres
Receiving
Put away
Replenish
Picking
Staging
Shipping
STORAGE
CROSS DOCK
DIRECT SHIP
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Postponement: customize products as late as possible
Distribution centres performing assembly, packaging, etc.
Vendor-managed inventory: let the vendor manage
ordering, warehousing, shipping, and placing products
IKEA, music CDs at department stores
Virtual integration: allow suppliers to access critical
information in real time
Retail Link at Wal-Mart: Point-of-Sales (POS) data shared with its
suppliers
Vertical integration: control the most or all of a supply
chain
McDonald’s in Russia
CPFR
See the next slide
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5. Supplier Relationships: CPFR
Collaborative Planning, Forecasting, and Replenishment
Process where trading partners share and discuss planning,
forecasting, and replenishment information in order to
work in partnership from a single forecast
Share forecast through the CPFR process
Share replenishment data through the supplier schedule
Guidelines for information sharing
Operating agreement
Voluntary Inter-Industry Commerce Standards (VICS)
Builds collaborative and strategic relationships
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Business Relationships
Open market
environment
- Multiple suppliers
- Short term decisions
Cooperative
- Fewer suppliers
- Longer term contracts
- Move away from price-based purchase criteria
- Win-win relationship
Collaborative
- Open exchange of information
- Joint planning
- Technology sharing - Strategic relationship
- Price based decisions
- Adversarial
Future: mass collaboration at the industry level?
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6. Sustainability in Supply
• Sustainability: Reduced use of resources, and harm to the
environment, so that the future is not threatened.
• Supply chain sustainability: refers to companies’ efforts to
consider the environmental and human impact of their
products’ journey through the supply chain, from raw
materials sourcing to production, storage, delivery and every
transportation link in between.
• Sustainable Supply Chain Management: Supply chain
management focuses on the speed, cost and reliability of
operations, while sustainable supply chain management
adds the goals of upholding environmental and societal
values. This means addressing global issues such as climate
change, water security, deforestation, human rights, fair
labor practices and corruption.
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Introduction
26
Key words in sustainability
Biodegradable: Something capable of decaying into its basic components.
Carbon emissions: Pollution released into the atmosphere from carbon
dioxide and carbon monoxide; often produced by motor vehicles.
Carbon footprint: The amount of carbon dioxide produced by your lifestyle.
Climate change: Significant change in climate including temperature,
precipitation, or wind that lasts for an extended period.
Compostable: Decomposition of organic material within a specific time
frame.
Eco-friendly: Environmentally minded actions that cause minimal harm to
the earth.
Fair trade: Principles of fair treatment, wages, and safe working conditions
for workers.
Greenwashing: Misrepresenting something as being “green” when it’s not
environmentally sound.
Recyclable: Items that can either be reused or broken down and converted
into new products.
Renewable energy: Electricity from replenishable sources such as
geothermal, hydropower, solar, and wind.
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Examples of sustainability in supply chains
• A road builder moved away from buying asphalt based only on
the price – result was a cut in shipping distance and related
carbon emissions by 40%.
• A fast-food company redesigned its packaging – eliminated
literal tons of waste.
• A grocery store in Canada launched using refillable packaging
for products such as ice cream, sauces, snacks, pet food, and
toothpaste – reducing plastic waste. And when delivering
products using route optimization to help ensure efficient
customer deliveries.
• A car producer with a plant the size of about 60 football fields
assembling some 375,000 cars each year and employing 5,500
people transformed its automotive assembly plant into a zerolandfill factory - lowering waste generation by 60% since 2000.
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Introduction
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6. Benefits from Supply Chain Improvement
Lower inventory
Shorter cycle time
Lower total cost
Higher service levels
Stronger relationship with supply chain members
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INVENTORY MANAGEMENT
Learning Objectives:
1. Purposes of inventory
2. Inventory control systems
3. Inventory costs
4. EOQ models
5. Safety stock
Formula
Sheet
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1. Introduction
Inventory: A stock of items or materials held to satisfy
eventual demand
Raw materials, purchased parts and supplies
Work-in-process (partially completed) products
Finished goods
Rework items
Tools, machinery, and equipment
Labour
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Types of inventory based on different purposes
Anticipation inventory to meet demand forecast (e.g.,
seasonality)
Safety stock buffer to protect against uncertainties
Lot-size inventory result of batch ordering
Pipeline inventory in transit
Hedge inventory to protect against future events (e.g., price
increase of raw materials)
Maintenance, Repair and Operating (MRO) inventory to
minimize disruptions to general operations and maintenance
Decoupling work-in-process items waiting for the next step
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Why keep inventory?
Buffer against expected & unexpected changes
Faster customer service
Economies of scale (production, purchasing)
Not to be dependent on suppliers
Why is too much inventory bad?
Cost (ties up working capital, may deteriorate or get stolen)
Need for storage space
Need for labour (material handling, transfer)
Complacency
General objective: To keep enough inventory to meet
customer demand and be cost efficient
Main operational concerns: When to order and how many
to order
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2. Inventory Control Systems
Different ways of determining when & how many to
order
Q system fixed quantity
P system fixed time period
ABC system
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2.1 Q System vs. P System
Q System
Reorder a fixed quantity (Q)
whenever the inventory falls to
or below a reorder point (R)
Continuous review system:
reviews the inventory each time
a withdrawal occurs
Time between orders varies
P System
Reorder after a fixed time period
(P)
Periodic review system: reviews
the inventory periodically
Order quantity (Q) varies
Q = (Target inventory level) –
(Current inventory level)
Compare in terms of record keeping system, administration cost,
responsiveness to demand variability, average inventory level, and
ease to combine orders to the same supplier
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2.2 ABC System
An inventory classification system in which a small percentage
of items (A-level) account for most of the inventory value
Level
% of units
% of dollar value
(e.g., annual volume x unit cost)
A
B
C
5-15
30
50-60
70-80
15
5-10
Step 1: Classify products into ABC categories
Step 2: Apply a different inventory policy to each category
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Inventory Management Policy (Example)
A items
B items
High priority
Tight control with
Moderate priority
Moderate control
C items
Low priority
Simple control
Carefully
Order quantities or
Large inventories,
regular review
determined Q,
frequent deliveries,
continuous review
Very accurate and
with regular attention
order points reviewed
quarterly
Batch updating of
inventory records
detailed inventory
records, update
monthly
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visual review
Simplified
counting, annual
review
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3. Inventory Management Costs
Ordering (set-up) cost: Fixed cost incurred whenever a
replenishment order is placed, regardless of the quantity
Requisition and purchase ordering, transportation and shipping,
receiving and storage, inspection, accounting and auditing costs
Holding (carrying) cost: Cost to keep one item in inventory
for a period of time (usually one year)
$ per unit per period or % of a unit cost/price
Rent, heating, cooling, lighting, security, record keeping costs
Interest on loans, depreciation, obsolescence, spoilage
Shortage (stockout) cost: Cost of not being able to meet
customer demand
Loss of sales, loss of future sales, loss of production, penalties
Backorder: the order is filled from the next shipment
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4. Economic Order Quantity (EOQ) Models
For managing anticipation inventory
Mathematical model for determining order quantity and
when to reorder
Assumptions:
Demand is independent, known, and constant
Supply is certain and received all at once in a batch
Replenishment lead time is known and constant
Lead time: Time between order placed and order received
Cost information is fixed and constant
No shortages and no back orders
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Order cycle time
= (No. of days in a year) / (No. of orders)
Formula
Sheet
EOQ Inventory Model:
Annual demand (D)
Inventory
Level
Order qty (Q)
Average daily
demand (d)
Reorder point (R)
R=dL
Formula
Sheet
0
Lead
time
(L)
Order
Order
Placed
Received
Lead
time
(L)
Order
Placed
Time
Order
Received
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4.1 Basic Model
Total annual inventory management cost (TC)
= (Annual ordering cost) + (Annual holding cost)
= (Ordering cost)(No.of orders)+(Holding cost)(Average inv.)
TC = CO (D/Q) + CH (Q/2) Formula
Sheet
EOQ objective: to minimize TC
EOQ = (2DCO / CH)½
Formula
Sheet
Annual
cost ($)
Total Cost
Minimum
total cost
Holding Cost = CHQ/2
Ordering Cost = CoD/Q
EOQ
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Order Quantity (Q)
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Example 1: Western Jeans Company (WJC) purchases denim from Huron
Textile Mills. WJC uses 36,000 yards of denim per year. The cost of
ordering denim from Huron is $500 per order. It costs Western $0.40 per
yard annually to hold a yard of denim in inventory.
a) What is the total inventory cost if each order is for 6000 yards?
b) What is the total inventory cost if denim is ordered every month?
c) Calculate the optimal order quantity and the total annual inventory cost.
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4.2 Economic Production Quantity (EPQ) Model
An order is received gradually, not all at once
Common when inventory user is also the producer
Inventory is depleted while it is being replenished
Inventory
level
Demand
rate (d)
Replenishment
rate (p-d)
Q-(Q/p)d
Average
inventory level
Q
(1-d/p)
2
Begin
order
receipt
End
order
receipt
Time
Production
& usage
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Maximum
inventory level
Usage only
44
Total annual inventory cost (TC)
= (Annual set-up cost) + (Annual holding cost)
= (Set-up cost) (No. of production runs)
+ (Holding cost) (Average inventory)
TC = CO (D/Q) + CH (Q/2)(1 – d/p)
Formula
Sheet
d = daily demand rate
p = daily production rate, where p > d
Optimal production quantity: EPQ = {(2DCO)/[CH(1 – d/p)]}½
Length of production run = Q/p
Max. inventory level = Q(1 – d/p)
Formula
Sheet
Formula
Sheet
Formula
Sheet
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Example 2: Western Jeans Company (WJC) produces and sells its own
jeans. The cost of setting up the production process to make jeans is
$150. The annual holding cost is $0.75 per pair, and the annual demand
is 10,000 pairs. The manufacturing facility operates 311 days a year and
produces 150 pairs of jeans per day.
a) What is the length of production run?
b) What is the maximum inventory level?
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5. Managing Safety Stock
Safety stock: Buffer added to on-hand inventory to protect
from demand/supply variability during the lead time
EOQ model considers only anticipation inventory and says
nothing about safety stock
General objective: to minimize shortage costs
Method 1: % of annual demand as safety stock
Simplistic but common
Method 2: Satisfy a specified service level
Service level: The probability that the inventory available
during lead time will meet demand
Service level method includes demand behaviour and
probability of stockout in consideration
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Q
Average
demand
during LT
Safety
Stock
Safety
Stock
0
Between
receipt &
order (P)
Lead
time (L)
Lead
time (L)
Time
Don’t worry about this
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Reorder
point (R)
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FORECASTING
Learning Objectives:
1. Qualitative vs. quantitative methods
2. Forecasting process
3. Time series methods
4. Forecast error measures
Formula
Sheet
Formula
Sheet
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1. Introduction
Forecasting: A method for translating past experience and
present events into predictions of the future
Forecasting in OM
Strategic: future products and markets
Planning: product demand
Forecasting horizon
Long-range (longer than 2 years) for strategy
Mid-range (weekly/monthly for up to 2 years) for planning
Short-range (hourly/daily for up to several months) for scheduling
Forecasting is important because
It is a starting point for business planning
All business decisions will follow the result of forecasting
“Bad” forecast can lead to a significant increase in cost
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2. Types of Forecasting Methods
Qualitative: based on opinions or judgement of
knowledgeable persons
Executive opinions, panel of experts
Market survey, focus group
Delphi method: to develop a consensus among experts
Quantitative: based on numerical data and
mathematical models
Causal methods: based on a known or perceived relationship
between the factor to be forecasted and other external or
internal factors linear regression
No calculation
Time series methods
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Qualitative vs. Quantitative
Qualitative
Quantitative
Subjective
Objective
Can incorporate a variety of
Can incorporate large a volume
Do not require numerical
Do not have to rely on few
Results may be biased
Numerical data may not be
information
of information
individuals
data
Results may be conflicting
available
Mathematical models may be
too simplistic
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1. Identify the purpose
3.Forecasting
Process
2. Collect historical data
Data
3. Examine data (plot)
4. Select appropriate models
Quantitative
5. Compute forecasts for historical
data and check forecast accuracy
6. Is accuracy acceptable?
No
Yes
7b. Adjust
parameters
or select new
model
7a. Forecast over planning horizon
8. Include qualitative information
Qualitative
9. Monitor results
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4. Time Series Forecasting Methods
Based on statistical analysis of historical data
Time series: a set of observed values measured over successive
time periods
Assumptions: (i) past demand is a predictor of future
demand, and (ii) record of past demand is available
Time series demand behaviour
Average stable over time
Trend general increase or decrease in average demand
Seasonality short-term periodic behaviour due to time of day,
day of week, month, season, etc.
Cycle long-term periodic behaviour due to product life cycles
Random variation any remaining variability that cannot be
explained; virtually unpredictable
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Cycle
Demand
Demand
Seasonal Pattern
Demand
Average
Time
Time
Time
Trend with Seasonal Pattern
Demand
Demand
Trend
Random
movement
Time
Time
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5. Time Series Forecasting Models
Naïve
Simple moving average
Weighted moving average
Exponential smoothing
Adjustment for seasonality
Data used in Examples 1-5:
Period (t)
Jan(1)
Feb(2)
Mar(3) Apr(4) May(5) Jun(6) Jul(7) Aug(8)
Demand (Dt)
12
18
22
20
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24
20
18
16
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5.1 Naïve Model
Relies only on demand in the current period
Short-term
Sensitive to random variation
Ft+1 = Dt
Formula
Sheet
Ft+1 = forecast for period t+1 (or for any future period)
Dt = actual demand in the most current period t
Example 1: Use the naïve model to forecast demand for September. How
about for October?
When would be a good idea to use the naïve model?
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5.2 Simple Moving Average
Relies on the recent past
Smooth out random variations
Useful for stable demand
Ft+1 = (Dt + Dt–1 + + Dt–(N–1))/N
Formula
Sheet
N = total number of periods used in calculation
Sensitivity to random variation depends on N
N is subjective
Example 2: Use a 3-period moving average to forecast demand for Sept.
What happens to a seasonal effect if this model is used?
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5.3 Weighted Moving Average
Weights represent the varying amounts of influence of past
demand on forecast
Weights also reflect fluctuations in the demand data
Ft+1 = Wt Dt + Wt–1 Dt–1 + + Wt–(N–1) Dt–(N–1)
Formula
Sheet
Wt = weight applied to period t’s demand
Weights are non-negative and sum to 1
Most common: most current demand has most influence
Weights and N are subjective
Example 3: Suppose W8 = 0.7, W7 = 0.2, and W6 = 0.1. Use a weighted 3period moving average to forecast demand for September.
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5.4 Exponential Smoothing
A special case of weighted moving average
Requires minimal amount of data (but includes all past
data)
Ft+1 = Dt + (1 – ) Ft
Formula
Sheet
= smoothing parameter (0<1); commonly 0.01–0.5
Low more smoothing; high more responsive to changes
is subjective
Example 4: Compute forecasts for Sept and Oct using exponential
smoothing with = 0.1. Assume F8 = 18.75, D8 = 16, and D9 = 14.
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5.5 Adjustment for Seasonality
Multiply unadjusted forecast (Ft+1) by a seasonal factor (Si)
Ft+1,i = Si Ft+1
Formula
Sheet
ATTENTION
Ft+1,i = forecast for season i in period t+1
Ft+1 = forecast for total demand in period t+1
Si = seasonal factor for season i = Di/Di
Di = actual total past demand for season i
Formula different
from textbook
Example 5: Forecast demand for each quarter in year 4 (Fyear4 = 30.4).
Year 1
Year 2
Year 3
Quarter
1 2
5.0 4.6
6.0 5.2
6.0 5.8
3
6.0
6.8
7.6
4
6.6
7.4
8.0
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5.6 Guidelines for Selecting Appropriate Models
Hypothesize based on demand patterns observed
If the underlying average is not changing:
Moving average with large N
Weighted moving average with large N
Exponential smoothing with small
If a trend exist:
Weighted moving average with large weight on recent demand
Exponential smoothing with large
If the underlying average exhibits seasonal patterns:
Seasonally-adjusted model
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6. Forecast Accuracy
Forecasts are rarely perfect
Internal factors, external factors
Modern issues more product choices, faster introduction of
new products
Small business issues lack of data, lack of expertise, time
constraint
Forecasting objective: to minimize forecast error
Forecast error = (Actual demand) – (Forecast) = D – F
To minimize error
Select the best possible model
Select the best possible value for a parameter
Forecasts are more accurate for a shorter term
Forecasts are more accurate for aggregate demand
Minimize forecast error measures: MAD, MAPD, MSE, CE
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Forecast Error Measures
Dt = actual demand in period t
Ft = forecast for period t
N = number of periods under consideration
Mean
Absolute
Deviation
Dt – Ft / N
Mean
Absolute
Percentage
Deviation
Dt – Ft / Dt
Mean
Squared
Error
Cumulative
Error
Formula
Sheet
Formula
Sheet
(Dt – Ft)2 / N
Formula
Sheet
(Dt – Ft)
Formula
Sheet
Measures general
variability
Smaller
the better
Forecast error
relative to demand
magnitude
Smaller
the better
Reveals large
errors
Smaller
the better
Measures bias
Large+, underestimate
Large, overestimate
Closer to 0
the better
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Example 6: Evaluate the following forecast model.
t
Dt
1
Ft
MAD
MAPD MSE
CE
170 200
30
17.7% 900
–30
2
230 195
32.5
16.3% 1063
5
3
250 210
35
16.2% 1242
45
4
200 220
31.3
14.7% 1031
25
5
185 210
30
14.5%
950
0
6
180 200
28.3
14%
858
–20
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7. Machine Learning (ML) in Demand Forecasting
• In recent years, machine learning has become an essential
component of reliable demand forecasting.
• Machine learning is a discipline within artificial intelligence (AI)
that uses advanced algorithms to learn from data. More
importantly, it uses data to automatically learn and improve
without human intervention.
• In demand forecasting, machine learning algorithms can
identify historical sales patterns and relationships in data,
allowing the computer to make predictions about future trends.
• While traditional methods use a set of predefined rules to
make predictions, machine learning is able to learn and adapt
from any amount of data.
• In 1997, IBM’s Deep Blue Chess (DBC) system managed to
defeat the World Chess Champion, Garry Kasparov, using
algorithms that were perfected through Machine Learning.
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7.1 Machine Learning Forecasting Process
1. Data gathering
• Historical data
• Information from social media
• Information about competitors products
• Information about future events
• Information from experts
2. Data pre-processing
• Remove noisy data
• Transforming data
• Standardizing data
3. model training
• ML algorithm is trained
• Selecting a model type and parameter values (done by the system)
4. model evaluation
• The performance of the model is then evaluated by comparing its
predictions against actual outcomes.
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7.2 Machine Learning Forecasting Example
Grocery retailers often place manual reorders, using “gut instinct” to
decide how much to order of fresh, perishable goods — such as fruit and
vegetables, meat, dairy and baked goods.
Freshflow: AI-powered forecasting platforms to help retailers optimize
stock replenishment, minimize food waste, and maximize revenue.
(https://freshflow.ai)
•
Freshflow’s premise is that ML can do a far better and less wasteful job of
restocking fresh food than the human eye, nose and gut by being able to weight
a variety of factors that may influence demand (for example, weather, season,
local events) and by evaluating available retailer data to create probabilistic
models and forecasts (for example, to predict the shelf life of various products),
to more accurately match overall supply and demand.
• Retailers saw a 30% reduction in food waste and a 16.7% increase in revenue
after around eight months of using the AI-powered system to automate fresh
produce restocking.
• The platform is designed to sit as a layer on top of the retailer’s existing
information system.
• The produce team uses an iPad app to inform them of recommended restock
quantities per product.
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7.3 Benefits of Machine Learning
1. ML can identify patterns that are too complex for humans to
observe.
2. ML can make predictions based on a much larger data set
than traditional methods.
3. ML is not easily influenced by human emotions or subjective
opinions.
4. ML can quickly adapt to changes.
5. ML is not easily manipulated by users as traditional methods.
6. ML uses human resources more efficiently than traditional
methods.
7. ML is more accessible than traditional methods.
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Start of Test 2
AGGREGATE PLANNING
Learning Objectives:
1. What is an aggregate production plan
2. Aggregate planning strategies
3. Generating basic aggregate plans
4. Modifying/improving the basic plans
5. Capacity strategies
Formula
Sheet
Formula
Sheet
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1. Introduction
Business Plan
e.g., new products, facility location
Aggregate Plan
Production plan to meet
aggregate demand
Master Production Schedule
Production plan for individual products
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Long term
2-10 years
Medium term
6-18 months
Short term
Weekly, daily
72
Aggregate demand: Demand for product lines or
product families
Aggregate production plan: A period-by-period plan of
production, workforce and inventory levels
Main concern: Do we have enough capacity?
Capacity shortage need to get more
Excess capacity how to effectively use the existing capacity
and resources
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2. Aggregate Planning Strategies
Active strategy: by influencing demand
Incentives, sales promotions, advertising campaigns, pricing
Products with countercyclical demand
Reactive strategy: by managing supply and capacity
Inventory, back orders, subcontracting
Overtime, undertime, hiring, firing
2 main approaches to the reactive strategy
Level constant production rate by no hiring/firing
Chase varying production rate by hiring/firing
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Chase Approach
Production “chases” demand
Constant production rate
Change production rate by
Demand variability dealt by inventory,
hiring/firing workers
back orders, overtime, undertime,
Good for make-to-order, service
subcontracting
Good for minimizing inventory
Good for make-to-stock
Bad for employee morale
Good for workforce stability
Level Approach
Bad for inventory buildup or stockouts
Demand
Production
Units
Units
Demand
Production
Time
Time
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3. Generating Aggregate Plans
Step 1: Choose level or chase approach
Step 2: Based on the approach chosen, determine the
following to satisfy aggregate demand
Production rate (regular, overtime, subcontracting)
Inventory level and back orders
Workforce level (hiring and firing)
Total cost = production cost + inventory cost +
workforce-related cost
Step 3: Modify or improve the plan
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Example 1: Develop an aggregate production plan for the following
aggregate demand:
Month
1
2
3
4
5
6
Demand
50
70
100 120 60
60
Cost and Production Information:
Production: Regular production cost = $10 per unit
Overtime cost = $15 per unit
Subcontracting cost = $20 per unit
Overtime production limit = max of 20 units per month
Production rate = 2 units per worker per month
Inventory: Holding cost = $2 per unit per month
Backorder cost = $5 per unit per month
Opening inventory level = 10 units
Labour:
Invt = Invt–1 + Prodt – Demt
(assumed to be computed
at the end of each period)
Formula
Sheet
Hiring cost = $200 per worker hired
Termination cost = $100 per worker terminated
Opening workforce level = 30
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Example 1a: Level approach based on the average demand
Average demand = (Total demand opening inventory) / (# of periods)
= (50+70+100+120+60+60 10)/6 = 75
Formula
Sheet
May use inventories and back orders
Level@
average
demand
Use cheapest first
TP = Reg + OT + Sub Formula
Sheet
Level
Opening
Inventory
formula
Reg = #WF
prod. rate
Formula
Sheet
Match WF
Level
Level
Opening
302=
7560=
Formula
TC = (production cost) + (inventory cost) + (workforce-related cost) Sheet
= (10360 + 1590 + 200) + (290 + 545) + (2000 + 1000) = $5355
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Example 1b: Level approach based on the highest demand
Highest demand in this example = 120 (period 4)
Guarantee no shortages in any period but build inventory
TC = (3600+1800+4800) + 1980 + 0 = $12180
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Example 1c: Level approach based on the max of cumulative average demand
Calculate the cumulative average (C.A.) for each period and choose the max
C.A. = (Total cumulative demand Open. inv.)/(# of cumulative periods)
Formula
Sheet
C.A. for period 1 = (Demand1 Open. inv.) / 1
C.A. for period 2 = [(Demand1 + Demand2) Open. inv.] / 2
C.A. for period 3 = [(Demand1 + Demand2 + Demand3) Open. Inv.] / 3
...and so on. Then choose the largest number among all the C.A.s calculated.
Guarantee no shortages with less inventory build-up
TC = (3600+1800+360) + 426 + 0 = $6186
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Example 1d: Chase approach
Production “chases” demand
Chasing
demand
TP/
prod.rate
Inventory
formula
Use cheapest first
TP = reg + OT + Sub
Reg = #WF
prod. rate
Match WF
5010=
TC = 4500 + 0 + (8000+4000) = $16500
If each worker produces 3 units per month, how would the plan change?
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4. Modifying or Improving the Aggregate Plan
Add organization policies, physical constraints, etc. to
a basic level/chase plan
For example, add min. or max. requirements, desired levels
Hybrid approach
3 specific “techniques” (Examples 2a to 2c)
2a: Keep the initial workforce but use overtime/subcontract
as needed
2b: Limit the use of overtime and subcontracting
2c: Desired level of ending inventory
May also improve objectives other than cost
Maximize customer service
Minimize changes in workforce levels
Minimize changes in production output
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Example 2a: Modify 1a keep the initial workforce level and use overtime
and subcontracting only when needed
Start from Example 1a
Check each period, starting from period 1, to see if regular production +
inventory is enough to meet demand; if enough, do not use OT/Sub; if not
enough, then use OT/Sub as needed
Period 1: (Reg + Inv = 60+10 = 70) > (Dem = 50) Do not use OT/Sub
Revised TP = 60+0+0 = 60 Revised Inv = 10+6050 = 20
TC = (3600+600+1000) + 60 + 0 = $5260
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Example 2b: Modify 1b – use hiring/firing to eliminate overtime and
subcontracting
Start from Example 1b
Determine the level of workforce that would eliminate the need for
overtime and subcontracting
For TP = 120 (from Example 1b), the workforce level of 120/2 = 60 would
eliminate the need for OT/Sub
TC = 7200 + 1980 + 6000 = $15180
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Example 2c: Modify 1c – the target inventory level at the end of period 6 is
10 units
Start from Example 1c, where the ending inventory for period 6 = 48
To achieve the target = 10, we need to reduce inventory by 38 units
In order to reduce inventory, we need to reduce production, starting from
period 6 and work your way up
Period 6: eliminate 3 from Sub & 20 from OT
Period 5: eliminate 3 from Sub & 12 from OT
Need to revise TP and Inv in periods 5&6
Total reduction in production
= 3+20+3+12 = 38 units
TC = (3600+1320+240) + 320 + 0 = $5480
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5. Capacity Planning
Do we have enough capacity?
If enough, are we operating at the best operating level (for example,
volume of output that results in the lowest average unit cost)?
Measuring capacity
Design capacity: Maximum output rate under ideal conditions
Utilizationdesign =(actual output rate)/(design capacity)
Effective capacity: Maximum output rate under normal conditions
Utilizationeffective =(actual output rate)/(effective capacity)
Capacity shortage
Should we outsource or expand?
If expanding, when to increase capacity and by how much?
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Capacity expansion strategies:
Average capacity
strategy
Capacity
Capacity
Time
Capacity
Time
Time
Units
By how much?
Capacity lag
strategy
Units
Capacity lead
strategy
Units
Units
When to increase capacity
One-step
expansion
strategy
Incremental
Expansion strategy
Time
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MATERIAL REQUIREMENTS PLANNING (MRP)
Learning Objectives:
1. What MRP is and does
2. Inputs and outputs of MRP
3. Scheduling basics
4. Scheduling sequencing rules
Formula
Sheet
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1. Introduction
Items
Production Planning
Capacity Planning
Resource level
Product lines or
families
Aggregate
Production Plan
Resource
Requirements Plan
Plants
Individual
products
Master Production
Schedule (MPS)
Rough-Cut
Capacity Plan
Critical work
centers
Components
MRP
Capacity Req’ts
Plan (CRP)
All work
centers
Manufacturing
operations
Shop Floor
Schedule
Input/Output
Control
Individual
machines
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Aggregate plan provides a framework for shorter-term
production and capacity decisions
Disaggregation: The process of breaking an aggregate plan into
more detailed plans
Material Requirements Planning (MRP): Computerized
inventory and production control system that determines
the requirements of dependent demand inventory
Introduced in the 1960s
Dependent demand inventory = parts, components, raw materials
Determine what is required, how much is required, and when it is
required
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2. MRP System Overview
Master Production
Schedule (MPS)
Inventory
Master File
Product
Structure File
1. Explosion: disassembly of the end product into its
components
2. Netting: (Net requirements) = (Gross reqts) – (Onhand inventory) – (Quantity on order)
3. Offsetting: order release is offset by production or
delivery lead time
4. Lot sizing: determine the batch size to be purchased
or produced
Formula
Sheet
Planned Order Releases
Work Orders
Purchase Orders
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Action Notices
92
2.1 Master Production Schedule (MPS)
States the requirements for individual end items by date and quantity
Aggregate Production Plan
Month
Days
Plan
Jan
21
21,000
Feb
19
19,000
Mar
23
23,000
Apr
20
20,000
2
4,000
1,000
5,000
3
5,000
4
2,500
2,500
5,000
MPS for April
Week
Prod X
Prod Y
Totals
1
2,000
3,000
5,000
5,000
MPS is Not
a sales forecast
a wish list
a final assembly schedule
MPS should be
anticipated build schedule
realistic and achievable
may not be feasible
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2.2 Inventory Master File
Description
Item
Item no.
Item type
Product/sales class
Value class
Buyer/planner
Vendor/drawing
Phantom code
Unit price/cost
Pegging
LLC3
Physical Inventory
On hand
Location
On order
Allocated
Cycle
Difference
Board
7341
Manuf.
Ass’y
B
RSR
07142
N
1.25
Y
Policy code
100
W142
50
75
3
-2
Inventory Policy
Lead time
Annual demand
Holding cost
Ordering/setup cost
Safety stock
Reorder point
EOQ
Minimum order qty
Maximum order qty
Multiple order qty
3
Usage/Sales
YTD usage/sales
MTD usage/sales
YTD receipts
MTD receipts
Last receipt
Last issue
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2
5,000
1
50
25
39
316
100
500
100
1,100
75
1,200
0
8/25
10/5
94
2.3 Product Structure File
Clipboard
Clip Assembly
(1)
Rivet
(2)
Top Clip
(1)
Bottom Clip
(1)
Pivot
(1)
Spring
(1)
Sheet
Metal
(8 in2)
Sheet
Metal
(8 in2)
Spring
Steel
(10 in.)
Iron
Rod
(3 in.)
Board
(1)
Pressboard
(1)
Finish
(2oz.)
Bill of material (BOM): lists which and how many items that go
into a product
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Example 1: Based on the product structure diagram on the previous slide:
a) How much spring steel is needed to fill an order of 500 clipboards if on-hand
inventory = 0? (Explosion & netting)
b) How much sheet metal is needed to fill an order of 1000 clipboards if on-hand
inventory = 7000? (Explosion & netting)
c) In order to produce 1000 clipboards, subassembly takes 1 day and final assembly
takes 1 day. For b), when should an order for sheet metal be placed if 1000
clipboards are needed by April 11? Order lead time = 5 days. (Offsetting)
d) In b), if the order lot size is 2000, how much would you order? (Lot sizing)
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3. MRP as an Analysis Tool
MRP is not a demand planning tool
Input quantities are production quantities, not demand
Production plan derived from aggregate production planning
MRP is deterministic
All input numbers are known
Problems show up as the action notices
Main MRP problem = shortage of components/finished goods
MRP is a simulation tool
Can estimate the production outcome identifies potential
shortage before actual production
Does not solve problems on its own requires human input
Solution examples: to purchase or produce more ahead of time; to move some
jobs forward (expediting) or backward (de-expediting)
Can show how the change in MRP input (i.e., a potential solution)
affects MRP output shows whether or not the solution would
work
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4. Production Scheduling
Allocation of resources to accomplish specific tasks
Last stage of planning before production
Scheduling objectives
Meet customer due dates
Minimize job lateness, response time, completion time, overtime,
idle time, and work-in-process inventory
Maximize labour or equipment utilization
Scheduling performance measures
Job flow time: total time a job spends in the shop incl. waiting,
setup
Makespan: total time to finish a batch of jobs
Average number of jobs in the system: measure of WIP inventory
Job lateness: ahead of, on, or behind the schedule
Job tardiness: how long after the due date the job is completed
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4.1 High Volume vs. Low Volume
High Volume Production
Low Volume Production
Length of a production run,
Coordination difficulty from
having a variety of orders, tasks
& process requirements
flow schedule, line balancing
Bottleneck: an operation with
the lowest effective capacity
Loading: assigns jobs to work
centres according to
performance efficiency, skill
requirements, and job priority
Optimized Production
Technology (OPT): a technique
used to schedule bottleneck
systems
Sequencing: determines the
Theory of Constraints (TOC): a
management philosophy that
extends the concepts of OPT
sequence in which jobs
assigned to a work centre are to
be processed
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4.2 Sequencing Rules
First come first served (FCFS)
Last come first served (LCFS)
Earliest due date first (EDD): min. tardiness
Shortest processing time first (SPT): min. average flow time
Longest processing time first (LPT)
“Formulas” for Scheduling Performance Measures:
Job flow time = (waiting time) + (processing time)
Makespan = finish time for the last job
Avg.# jobs in the system=(all jobs job flow ime)/(makespan)
Job lateness = all jobs (finish time due time)
Job tardiness = only late jobs (finish time due time)
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Formula
Sheet
Formula
Sheet
Formula
Sheet
Formula
Sheet
Formula
Sheet
10
0
Example 2: A hospital lab has one MRI, and 5 patients need scheduling.
Job:
A
B
C
D
E
Processing time (hrs):
4
7
2
6
3
Pickup time (hrs from now): 6
12 7
16 8
Sequence
Flow time
=wait+process
Tardiness
=finish-due
Avg.
Tardiflow
ness
time
FCFS
LCFS
EDD
SPT
LPT
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4.3 Other Types of Operations Scheduling
Scheduling in services
Complicated because demand is often variable and difficult to
forecast
Service scheduling: appointments, reservations, posted
schedules, backlogs
Staff scheduling: peak demand, floating, on-call, seasonal, parttime
Maintenance scheduling
Repair scheduling
Preventative maintenance
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ENTERPRISE RESOURCE PLANNING (ERP)
Learning Objectives:
1. What is ERP
2. Historical development of ERP
3. ERP enablers
4. Implementation issues
5. Project management basics
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1. Introduction
• Enterprise Resource Planning (ERP): Software with
integrated modules for controlling and coordinating
business processes of an entire enterprise
• Manufacturing information systems as the origin:
• MRP
• MRP + CRP
• MRP II
• ERP
1960s
1970s
1980s
1990s to present
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2. Information Systems
A collection of components that work together to provide desired
information in the proper format at an appropriate time
ERP is one type of IS
People
Software
Data
Hardware
Information
Procedures
Information Technology
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105
ERP is one type of transaction processing systems
Maintain a huge volume of transaction records sales, purchases,
customers, creditors, banking
ERP is one type of information reporting systems
Provide various reports
Provide information for managers Management Information
Systems (MIS)
ERP is not a functional (departmental) information system;
it consists of all key functional modules
Accounting accounts receivable/payable, payroll records,
budgeting, financial planning
HR personal data, job skills, training history, pay rates, insurance,
vacation days, sick leave time
Marketing sales orders, buying trends, customer databases,
product information, advertising records
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3. MRP + CRP (1970s)
MRP ensures that material requirements are met
Capacity Requirements Planning (CRP): checks for the
availability of labour and/or machine hours
CRP identifies capacity overload and underload
CRP does not solve problems on its own
Human intervention required for deciding:
Overtime or reduce work load
Push back a job or pull ahead a job
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4. MRP II (1980s)
Manufacturing Resource Planning (MRP II): Extension of
MRP that plans all resources needed for running a business
MRP + CRP + Finance + Marketing
Finance access to accurate reliable operations numbers
Sales less trouble shooting, more selling, able to promise
HR easier to assess performance measures
Limitations
Limited functional integration
Often limited to one location
No supply chain capabilities
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5. ERP (Since 1990s)
To create the information linkages that integrate the
processes and structures within a supply chain
MRP II + Supply Chain Management + Global Presence
Operations
& Logistics
ERP
Sales &
Marketing
Customers
Suppliers
Finance
HR
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5.1 ERP Technological Enablers (Building Blocks)
Advancement in electronic communication
For example, technology behind e-mails and e-bulletin boards
Electronic data
Bar codes and electronic scanning
Advancement in computer-to-computer data sharing
Electronic Data Interchange (EDI): Computer-to-computer
exchange of business documents in a standard format
Electronic Funds Transfer (EFT): Computer-to-computer
exchange of funds
Data conversion software
Internet
e-commerce; shared databases; cloud storage
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5.2 ERP Mixed Results in the 1990s
• Popularity of ERP systems soared after an introduction of
SAP’s ERP software, R/3, in 1994
• Other big ERP vendors: Oracle, Microsoft, Deltek, and Sage
Success/Benefits
Nightmare in the 1990s
Cisco Systems, Kodak
Lower inventory levels
Lower workforce costs
On-time completions
Better coordination among
different functional areas
Better communication
Better data integrity
FoxMeyer Drug bankruptcy
Law suits (Boeing, Dow Chemical,
Mobil Europe, Hershey, Kellog’s)
Dell Computer scrapping SAP’s
ERP software
1999 survery 40% partial
implementation, 20% scrapped
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111
5.3 ERP Implementation Issues
Technical:
Handling large amounts of data
Inaccurate data, loss of data
Insufficient training
Lack of understanding of what ERP is or does
Behavioural:
Lack of support by management
Lack of commitment by employees
Coordination difficulty among different functions
Ownership claim problem (too much vs. too little)
Unrealistic expectations, unrealistic promises
Not understanding the underlying needs
Changing habits
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6. Project Management
Project: one-at-a-time product exactly to customer
specifications
Project management: application of knowledge, skills,
and techniques to project activities in order to meet
stakeholder needs
Project manager must
Balance scope, time, cost and quality
Manage multiple stakeholders with differing needs
Satisfy identified requirements (needs) & unidentified requirements
(expectations)
Project life cycle
1. Concept identify the need for the project
2. Feasibility analysis evaluate costs, benefits, and risks
3. Planning decide who does what and how long
4. Execution do the project
5. Termination end the project
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Topics Covered By Project Management Institute:
Scope
Human resources
Time
Cost
Quality
Risk
Procurement
Communications
Integration
See next 3 slides
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6.1 Project Scope Management
To ensure that the project includes all the work required,
and only the work required, for successful completion
Project scope work that must be done for delivering a product
Product scope features and functions of a product or service
Scope planning
Product description, formal recognition of business need
Constraints and assumptions
Scope definition
Cost, time and resource estimates, how to measure performance,
and clear responsibility assignments
Scope change control
How to deal with scope changes, corrective action, and lessons
learned
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6.2 Project Human Resource Management
Organizational planning
Project roles, responsibilities, and reporting relationships
Communication planning
Distribution structure, record keeping structure
Status and progress reporting, expectations
Staff acquisition
What skills are required from which individuals or groups, when
and how long
Team development
Training, meetings, “war room”
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6.3 Project Time Management
Time Tracking Tools
Gantt chart: visual representation of a schedule over time
Load chart: shows the planned workload and idle times
Progress chart: shows planned and actual progress
Project management software (for example, Microsoft Project)
Time Estimate Techniques
Critical Path Method (CPM): identify the critical path using a
network diagram with deterministic time estimates
Critical path: a set of activities that would cause an overall project
delay if any of them is late
Program Evaluation and Review Technique (PERT): probabilistic
time estimates
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End Here for Test 2
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Final Exam Start Here!
PROCESS AND PRODUCT DESIGN
Learning Objectives:
1. Process types
2. Facility layout types
3. Manufacturing technology
4. Product design basics
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1. Introduction
Process: How to transform input into output
Classification by
Type of product flow (fixed position, jumbled flow, line flow,
continuous flow)
Approach to customer orders (make-to-order, make-to-stock,
assemble-to-order)
Amount of customization
Our focus demand volume vs. product standardization
(product variety; the level of customization)
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2. Classification by Volume and Standardization
Product Standardization
Intermittent
operations
Low
Project
Repetitive
operations
Batch
process
Mass
process
Continuous
process
High
Low
High
Product Volume
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Project: one-at-a-time product exactly to customer specifications
Batch: small quantity of products in batches based on actual or expected
customer orders
Mass: large volume of a standardized product, assembly line format
Continuous: continually produce a very high volume of a fully
standardized product
Product variety
Approach to customer orders
Product flow
Type of equipment
Degree of automation
Critical resources
Throughput time
WIP inventory
Intermittent
Repetitive
Great
Small
Make-to-order
Jumbled
Make-to-stock
General purpose
Line
Specialized
Low
Labour
Longer
More
High
Capital
Shorter
Less
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3. Process Type and Facility Layout
For intermittent operations
Process layout: groups resources based on similar processes
Warehouse layout, office layout
For repetitive operations
Product layout: groups resources based on products
Arranges resources in sequence (assembly lines)
Hybrid between process and product layouts
Cell layout: grouping of products based on similar requirements
(processes)
Fixed-position layout: used when the product is too big and
cannot easily be moved (e.g., bridge construction)
Retail layout: allocates space based on customer behaviour
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Process layout
Radiology
Laboratory
Lobby
Exam room
Surgery
Physical
therapy
Product
layout
A
A, B, C
1
A
1
4
B
2
5
C
3
6
2
1
3
2
Cell
layout
3
5
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4
124
Product Standardization
4. Process Type and Technology Adoption
Intermittent
operations
General
Low purpose
Group
Technology
Repetitive
operations
FMS
Focused
automation
Dedicated
automation
High
Low
High
Product Volume
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Manufacturing Technologies
Group technology
Grouping of dissimilar automated machines to produce a family
of parts
Flexible manufacturing system (FMS)
Consists of numerous programmable machine tools connected
by an automated material handling system
Robotics
Controlled by a computer; can perform complex tasks
Computer-aided manufacturing (CAM)
Controlling manufacturing through computers
Computer-integrated manufacturing (CIM)
Integration of product design, process planning, and
manufacturing through computers
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5. Process Selection
Cost, volume, product maturity level, labour/technology
availability
Matching process and corporate strategy
Intermittent
Repetitive
Corporate strategy
Customized products
Mass market
Operations strategy
Low volume, customized service High volume
Competitive priorities
Volume flexibility, customization Low cost
Matching process and product product design
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6. Product Design
Process of defining all of the product’s characteristics
General steps in product design
1. Idea development (customer driven, reverse engineering, R&D)
2. Product screening (feasibility study)
3. Preliminary design and testing
4. Final design
Faster introduction of new products
Concurrent engineering: Multifunctional team approach to
simultaneously design the product and the process
Computer-aided design (CAD): Use of computer graphics to design
new products
3D printing: Method of making an object by adding thin layers of
materials layer-by-layer based on CAD
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JUST-IN-TIME SYSTEMS
Learning Objectives:
1. JIT origin and philosophy
2. JIT key elements
3. Implementation issues
4. Job design basics
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1. Introduction
Just-in-time (JIT) manufacturing: To produce only what
is needed, when it is needed
JIT inventory, JIT purchasing, lean manufacturing
JIT philosophy: Eliminate all waste in the organization
JIT system: A management system that aims to improve
the manufacturing or service process by eliminating waste
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1.1 Origin of JIT Systems
In the 1950s, the Japanese were short on capital and space
For Toyota (Taiichi Ohno), to improve performance meant to
reduce inventory
Inventory hides problems
Reducing inventory led to reducing all kinds of waste
Machine
breakdowns
Poor
quality
Poor
design
Poor
vendors
Inefficient
layout
Long
setups
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1.2 Types of Waste
Waste: Anything other than the minimum amount of resources that is
essential to add value to the product
Process
Waiting time
Unplanned
Planned queue
Waiting for other parts in batch
Scrap
Non-value-added cost
Wrong tools/equipment
Over-production
Extra inventory
Inappropriate use of resources
Inventory
Storage
Capital costs
Product defects
Interrupted flow
Lost capacity
Wait for replacement
Methods
Searching for tools
Poor layout
Walking
Movement
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Material handling
Receiving
Storing
Retrieving
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2. Key Elements of JIT Systems
Work cells efficiency within a process, multi-functional
workers
Pull system coordination between processes
To improve the pull system, reduce the variability associated
with supply and demand
To control supply variability
Small lot sizes
Preventive maintenance
High quality
Reliable suppliers
To control demand variability
Uniform loading
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2.1 Work Cells
Eliminate worker inefficiency increase worker
productivity
Operation of a number of different machines highly
utilized, multi-functional workers
Cellular facility layout: work is moved within a cell (mostly
U shaped) according to a prescribed path
Different from traditional automobile production, which is mass
production of standardized products using assembly lines
Flexible machines
Automated, general purpose machines
Quick setup time
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Work Cell Example
Machines
Product
route
Worker
2
Worker
1
Worker
3
Exit
Cell: grouping of products based on similar requirements
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2.2 Pull Production System
Improve poor coordination between processes eliminate
the need for large inventory
Major problem in automobile manufacturing
Push system: Each workstation produces according to a
schedule and “pushes” its completed work to the next
workstation
Traditional approach to production; builds inventory
Pull system: Each workstation requests, or “pulls”, items
from the previous workstation only when needed
Prevent overproduction and underproduction
Force coordination between processes kanban system
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Kanban system: A visible production control system which
authorizes the production or movement of the next batch
of material only when needed
Kanban: a Japanese word for “signal” or “visible record”
Most common form: card, container
Kanbans are not schedules
Work the same way as a fixed-quantity inventory system
where order quantity (Q) equals to the reorder point (R)
Only inventory maintained is the amount needed to cover usage
until the next order arrives
MRP vs. Kanban
Schedule vs. cue
Complex vs. repetitive
Higher-level vs. shop-level control
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2.3 Supply Variability #1: Lot Sizes
Each kanban “container” represents the production or order
lot size
Small lot sizes provide many benefits
Better coordination
Better material handling
Reduce average inventory level
Reduce inventory space
Avoid buildup of defective items
Flexibility in reacting to problems
Quick set-up is crucial
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2.4 Supply Variability #2: Machine Breakdowns
Maintenance: To keep facilities and equipment in good
working order
Machine downtimes are waste fix fast fixing is
also waste
Preventive maintenance: Periodic inspection and
maintenance designed to avoid breakdowns
Preventive vs. breakdown maintenance
Necessary due to small inventory and high automation
Work environment: Five S’s
Seiri (housekeeping), Seiton (workplace organization), Seiso
(clean-up), Seiketsu (keep clean), Shitsuke (discipline)
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2.5 Supply Variability #3: Quality
Consistently high quality products are necessary due to
small inventory
Quality at the source: uncover the root cause
Andon lights to signal problems
Empowerment: authority given to workers to stop the
production line if a problem occurs
Preventive
Poka-yoke: devices that are designed to prevent
mistakes/defects from happening
Standard parts, modular design: reduce variability
Continuous improvement (“kaizen”)
Quality Circle: team-based process improvement
Under-capacity scheduling to deal with problems daily
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2.6 Supply Variability #4: Suppliers
Need reliable suppliers for on-time, frequent deliveries
Must build long-term, close relationships with few suppliers
Single sourcing: entire family of parts provided by one supplier
JIT II: supplier working in the manufacturer’s plant
Physical proximity is preferred but not necessary
From the supplier’s point of view:
Guaranteed, steady demand
Advanced notice of volume changes
Minimal design changes
Lots of requirements
Competitive vs. cooperative dilemma
“All eggs in one basket”
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2.7 Demand Variability
Cells can deal with changes in product mix and volume
to a certain extent
Volume adjustment by a number of workers
Volume adjustment by integrating or separating cells
Kanban system can absorb 10% variability in demand
by manipulating the number of kanbans
The fewer kanbans, the less production
At Toyota, container size is at most 10% of daily demand
Uniform loading: Arrange daily production mix in the
same ratio as monthly demand
Always have some quantities of each product
Steady demand on components
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3. Before and After JIT
Before
Inventory to protect against
problems & uncertainty
Assembly lines
Push manufacturing
Tolerate defects
Tolerate setup times
Emphasize work of individuals,
following manager instructions
Treats suppliers as independent
entities
After
Reduce inventory
Cells
Pull manufacturing
Zero defects
Reduce setup times
Emphasize team-oriented
employee involvement
Suppliers as partners
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4. Benefits of JIT Systems
Reduced inventory
Reduced space
requirements
Improved quality
Improved process
Better use of human
resources
Better relations with
suppliers
Increased employee
participation
Shorter cycle time
Shorter lead time
Greater flexibility
More product variety
Increased productivity
Increased machine
utilization
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5. JIT Implementation Issues
All key elements must be present and integrated for the
system to work well
Must balance technical and behavioural aspects
Each organization must mould a JIT system to suit its own
environment
JIT system requires a fundamental change in the
organization
Not suited for
Very high volume
Very low volume, unique products
Highly fluctuating demands or true make-to-order products
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6. Job Design
Job design: specifies the contents of the job
Automation
Good for repetitive, computational, precise or physical tasks
Not good for people interaction, creativity, multiple variables
Management
Readily available labour
Minimal training
Reasonable wage
High productivity
High absenteeism
High turnover rates
High scrap rates
Grievances filed
Workers
Specialization: performing single or limited tasks
Minimal credentials
Minimal responsibilities
Minimal mental effort
Reasonable wage
Boredom
Little growth opportunity
Little control or initiative
Little intrinsic satisfaction
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Alternative job designs
Job rotation: shifts workers to different jobs to increase
understanding of the total process
Job enlargement: expansion of the job through increasing the
scope of the work assigned
Job enrichment: expansion of the job through increasing the
worker responsibility
Teams
Problem-solving teams
Special-purpose teams
Self-directed teams
Work measurement
Method analysis: the study of how a job is done
Time study method: sets a standard time based on timed
observations of one worker over several cycles
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147
148
QUALITY
Learning Objectives:
1. What is quality
2. Quality measures
3. Costs of quality
4. Process improvement
5. Continuous improvement
Formula
Sheet
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1. What is Quality?
Meaning of Quality: degree of excellence
Product based
Quality of
Design:
Degree to which
quality
dimensions are
designed into the
product
Producer’s perspective
Quality of
Conformance:
Degree to which a product
conforms to required
specifications
Consumer’s perspective
Fitness for use:
Degree to which a product
satisfies customer’s wants
Value-based:
Degree to which a product
provides acceptable quality at
a reasonable price
American Society for Quality:
The totality of features and characteristics that satisfy needs
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2. Dimensions Of Quality
Products
Services
standards
Reliability: frequency of failure
Durability: length of product’s life
Serviceability: ease of getting
repair
Aesthetics: appearance
Safety: not causing injury or harm
Perceived quality: reputation &
intangibles
convenience
Accuracy, competence
Completeness
Consistency
Courtesy
Responsiveness to unusual
circumstances
Communication
Security
Credibility
Performance: basic characteristics
Features: “extra” items
Conformance: meeting pre-set
Time and timeliness
Accessibility and
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3. Quality Measures
Scrap, rework, number of errors, premium shipping cost
Product yield:
Yield = (#Units to produce)(%Good units)
+ (#Units to produce)(1 %Good units)(%Reworked)
Formula
Sheet
Quality index: report quality cost relative to some base
value (indexing)
Labour index = (Quality cost) / (Direct labour hours)
Cost index = (Quality cost) / (Production cost)
Sales index = (Quality cost) / (Sales)
Production index = (Quality cost) / (Product yield)
Quality-productivity index=(Product yield)/(Production cost)
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Formula
Sheet
Formula
Sheet
Formula
Sheet
Formula
Sheet
Formula
Sheet
152
4. Costs of Quality
All costs, tangible and intangible, relating to managing the
quality of a good or service
Costs of poor quality (failure costs)
Internal failure: costs of scrap, rework, downtime, material losses
External failure: costs of product returns, repairs, recalls, warranty
claims, customer complaints, and lost sales costs
As product quality , failure costs
As internal failure costs , external costs may or may not − why?
Costs of good quality (control costs)
Appraisal: costs of testing and inspection (equipment, operators)
Prevention: costs of preparing and implementing a quality plan
(product/process design, training, information costs)
As product quality , appraisal costs but prevention costs may or
may not − why?
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Costs of good quality vs. costs of poor quality
(source: Schneiderman, 1986)
Total cost
Total cost
Failure
costs
Failure
costs
Control costs
Control costs
0%
Optimal
quality
100%
0%
Pre-“zero defects”
mentality
“Zero defects” mentality
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100%
Optimal
quality
154
5. Quality and Profitability
Improved
quality
Higher sales
- Improved response
- Improved reputation
- Higher prices
- Increased market share
Higher
profits
Lower costs
- Lower rework & scrap
- Lower warranty & liability
- Increased productivity
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6. Quality Improvement
Process improvement: Final product inspection is too late
must improve the production process
Eliminate common causes (e.g., poor design)
Eliminate special causes (e.g., specific equipment)
Continuous improvement: A philosophy of never-ending
pursuit of high product quality
Innovation vs. continuous improvement: big jumps vs. small steps,
dramatic vs. not dramatic, specialists vs. everyone
Quality of design: Built-in quality in the product or service
design
Quality Function Deployment (QFD): a tool to translate the
customer preferences into specific technical requirements
House of quality
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6.1 Process Improvement Tools
Check sheet
To initiate process improvement by recording quality problems
Histogram, Pareto chart
To prioritize quality problems
Cause-and-effect (fishbone, Ishikawa) diagram
To identify possible causes of a quality problem; good for
brainstorming
Scatter diagram
To narrow down to one cause
Flow chart
To identify the cause of a quality problem by tracing the
production process
Statistical Process Control (SPC) chart
Quality monitoring
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Histogram: shows
the frequency of
quality problems
Check sheet: factfinding tool; tally the
number of problems
Pareto chart: shows %
of the frequency of
problems
Problem
Late
Missing
Broken
#
%
Cause-and-effect diagram: identifies all possible
areas to which quality problems may be related
Receiving
Supplier
Shipping
Machine
Workers Material
Late
order
Flowchart: focus on
where in a process a
quality problem
might exist
Temperature
Statistical process
control chart:
monitors whether or
not the process is in
control over time
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Scatter diagram:
shows the
relationship
#
between two
variables
158
6.2 Continual Improvement Tools
Deming Wheel: 4 stage-process (a.k.a. PDSA or PDCA cycle) for
continual quality improvement
1. Plan
Identify problem
and develop plan
for improvement
4. Act
Institutionalize
improvement
2. Do
Implement plan
on a test basis
3. Study/Check
Check to see
if the plan is
working
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Quality Circle: Team-based approach to continuous quality
improvement
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STATISTICAL PROCESS CONTROL (SPC)
Learning Objectives:
1. 4 stages/levels of quality management
2. Acceptance sampling vs. SPC
3. SPC steps
4. Attributes vs. variables
5. 4 SPC charts
6. Pattern tests
7. Process capability basics
Formula
Sheet
Formula
Sheet
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1. Quality Management
Four stages
Quality inspection: focus on providing information
Quality control: focus on monitoring and controlling
SPC
Quality assurance: management programs aimed at
ensuring good product quality by setting minimum or
desired levels of quality
Total Quality Management (TQM): management
philosophy about ensuring and improving product
quality throughout the entire organization
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2. Quality Inspection
When
Upon receipt of resources
Before transformation operations (especially bottleneck)
The first few items coming out of an automated operation
Final inspection
Customer complaints and returned goods
How much and how often
Complete inspection vs. sampling
Cost of inspection vs. cost of not detecting defects
Cost, time and physical possibility
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3. Acceptance Sampling
The method of randomly inspecting a sample of goods and
deciding whether to accept the entire lot based on the
results
1.
2.
3.
Take a random sample from a lot (batch) of items
Test the sample items for the specified quality characteristics
Accept all items in the lot if
(Number of defective items in the sample)
< (Maximum number of defective items allowed in a sample)
Otherwise, reject all items in the lot.
Historical mentality: “some degree of poor quality will occur
and that is acceptable”
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4. Statistical Process Control (SPC)
To prevent poor product quality
Process improvement tool
Method of randomly inspecting a sample of goods and
deciding whether the production process is in control
Monitor the production process (data pattern)
Provide a statistical signal when the process (quality) changes
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4.1 General Steps in SPC
Step 1: Define the quality characteristic to measure
Step 2: Set up a control chart
Step 3: Take a random sample and plot the quality measure
Step 4: Is any sample point
outside of the control limits?
Yes
No
Step 5: Does any
pattern exist?
The process is in control
(continue monitoring)
No
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Yes
Step 6: The
process is out of
control;
stop the process
until the quality
problem is
identified and
fixed
166
Step 1: Define the quality characteristic to measure
Attributes: characteristics that are measured qualitatively,
thus have discrete values
For example, defective/non-defective, # of scratches or blemishes
Count both defective and non-defective items p-chart
Count defective features in an item c-chart
Variables: characteristics that are measured quantitatively,
thus have continuous values
For example, weight, length, volume, temperature
Difference (range) between smallest and largest values R-chart
Average x-chart
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Step 2: Set up a control chart
UCL (Upper
Control Limit)
3 Sigma Limits
Process Average
3 Sigma Limits
LCL (Lower
Control Limit)
1
2
3
4
5
6
7
8
9
10
Sample number
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Step 3: Take random samples over time. For each sample,
measure the quality characteristic and plot the result.
UCL
Process Average
LCL
1
2
3
4
5
6
7
8
9
10
Sample number
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Key ideas behind the control limits:
In spite of inherent random variation in a production
process, the average of the distribution of the quality
characteristic should be stable if the process is in control
The range between the UCL and LCL allows for random
variation
Observations falling outside the UCL or LCL indicate the
existence of abnormal variation
Control limit standard = 3-sigma limits
Control limits too narrow Type I error: random variation
mistaken for an abnormal variation
Control limits too wide Type II error: abnormal variation may
not be detected
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Step 4: Is any sample point outside of the control limits?
Yes the process is out of control (step 6)
No go to step 5
Step 5: Does any pattern exist? (Pattern tests)
Yes the process is out of control (step 6)
No the process is in control continue monitoring
(step 3)
Step 6: Identify and correct the quality problems
Process improvement tools
Discard out-of-control sample observations
May need to revise the control chart
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4.2 p-Chart: Control Chart for Attributes
Quality to be measured: proportion of defective items
Sample size (n): 30-100 items per sample (guideline)
Center line: p = historical average proportion of defects
UCL = p + z [ p (1 – p)/n]1/2
LCL = p – z [ p (1 – p)/n]1/2
Formula
Sheet
Formula
Sheet
Sample
standard deviation
z = number of standard deviations corresponding to the sigma limit
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Example 1: A soft drink bottler is concerned about over- and under-filled
bottles. Management desires 3-sigma control limits. 10 samples (200
bottles per sample) have been collected.
a) Is the process in control?
b) The first day on the job, a machine operator takes a sample of 30 units
and finds 5 units to be defective. Should you be concerned?
Sample
1
2
3
4
5
6
7
8
9
10
# of defects p
12
0.06
16
0.08
8
0.04
24
0.12
20
0.10
4
0.02
16
0.08
12
0.06
28
0.14
8
0.04
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Control chart for Example 1:
0.18
0.16
0.14
0.12
0.10
0.08
0.06
0.04
0.02
0
1
2
3
4
5
6
7
8
9
10
Sample number
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4.3 c-Chart: Control Chart for Attributes
Quality to be measured: # of defective features per item
Sample size: 1 item per sample
Used when it is not possible to count non-defective items
(i.e., no proportion of defectives can be computed)
Center line: c = historical average # of defective features
UCL = c + z ( c )1/2
LCL = c – z ( c )1/2
Formula
Sheet
Formula
Sheet
Sample
standard deviation
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Example 2: An airline company wishes to set up a control chart to monitor
the number of misplaced luggage. One flight is selected at random each
hour, and the cases of misplacement are counted.
a) Is there any concern regarding misplaced luggage? Use 3 sigma limits.
b) The 7th flight had 11 cases of misplacement. Should you be concerned?
Flight
1
2
3
4
5
6
# of misplacement
6
3
9
6
9
3
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Control chart for Example 2:
18
16
14
12
10
8
6
4
2
0
1
2
3
4
5
6
7
8
9
10
Sample number
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4.4 R-Chart: Control Chart for Variables
Quality to be measured:
R = (Largest value in the sample) – (Smallest value)
Sample size (n): 2-10 items per sample
Center line: R = historical average of R values
UCL = D4 R
Formula
Sheet
LCL = D3 R
Formula
Sheet
D3 and D4 = range value constants based on sample size
• Specifically developed to determine control limits for R-chart
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4.5 x-Chart: Control Chart for Variables
Quality to be measured: sample average
Sample size (n): 2-10 items per sample
Center line: x = historical average of x values
UCL = x + A2 R
Formula
Sheet
LCL = x – A2 R
Formula
Sheet
A2 = mean value constant based on sample size
• Specifically developed to determine control limits for x-chart
R-chart and x-chart should be used together - why?
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Control Limit Factors
for R-chart and x-chart
with 3-sigma limits
Formula
Sheet
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Example 3: University Food Services uses SPC to monitor the length of
time from when an order is placed with a supplier to when the goods
arrive at the receiving dock (“order cycle time”). When the process is
in control, x = 1.13 days and R = 0.5 days based on samples of size 5. Is
the process in control? Use 3 sigma limits.
Sample1
1.1
1.2
1.1
1.1
1.0
Sample2
1.2
1.1
1.2
1.1
1.0
Sample3
1.0
1.0
1.8
1.0
1.0
Sample4
0.8
1.1
1.2
1.2
1.9
Sample5
1.1
1.0
1.0
1.0
1.2
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Control charts for Example 3:
R chart
x chart
1.6
1.6
1.4
1.4
1.2
1.2
1.0
1.0
0.8
0.8
0.6
0.6
0.4
0.4
0.2
0.2
0
1
2
3
4
0
5
2
3
4
5
Sample number
Sample number
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1
182
5. Pattern Tests
To detect a non-random pattern within the control limits
Run tests: check for the runs
Run: a sequence of observations with a certain characteristic
Pattern 1: 8 consecutive points on one side of the center line
Pattern 2: 8 consecutive points up (or down)
Pattern 3: 14 points alternating up-down-up-down…
Zone Tests: check for the zones
3 zones for 3 sigma limit control charts
Pattern 4: 2 out of 3 consecutive points
UCL
Formula
Sheet
Formula
Sheet
Zone width = (UCL − Center)/3
MOS 3330: SPC
Formula
Sheet
Zone A
Zone B
in zone A
Pattern 5: 4 out of 5 consecutive points Center
in zone A or B
Formula
Sheet
Formula
Sheet
Formula
Sheet
LCL
Zone C
Zone C
Zone B
Zone A
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UCL
LCL
UCL
LCL
Consistently below pattern 1? (not yet)
UCL
UCL
LCL
LCL
Upward trend pattern 2? (no)
Alternating up&down pattern 3? (not yet) Close to boundarypatterns 4&5? (yes)
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Example 4: Is the process in control? x=1.47, UCL=2.05, LCL=0.89
Sample
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
x
1.4
1.3
1.2
1.36
1.56
1.6
1.7
1.53
1.66
1.43
1.87
1.65
1.4
1.78
1.9
1.7
1.83
1.5
1.88
1.1
Above/Below
B
B
B
B
A
A
A
A
A
B
A
A
B
A
A
A
A
A
A
B
Up/Down
Zone
--D
D
U
U
U
U
D
U
D
U
D
D
U
U
D
U
D
U
D
C
C
B
C
C
C
B
C
C
C
A
C
C
B
A
B
B
C
A
B
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185
6. Process Capability
SPC monitors natural vs. non-random variation within a
process producer’s perspective
Process capability: The ability of a process to satisfy a
product’s or service’s tolerances
Tolerances: Design specifications that reflect customer
requirements
Upper Tolerance Limit (UTL), Lower Tolerance Limit (LTL)
Not statistically determined
Not a result of production process
Production process must be in control (check SPC) and
must meet design specifications (check process capability)
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How to assess process capability: compare specification
width against process width
Process capability index (Cp)
= (specification width) / (process width)
Formula
Sheet
Rough guideline
Process is capable of meeting specifications if
(UTL LTL) = (UCL LCL) Cp = (UTL LTL) / (UCL LCL) = 1
Process is capable of exceeding specifications if
(UTL LTL) > (UCL LCL) Cp = (UTL LTL) / (UCL LCL) > 1
Process is not capable of meeting specifications if
(UTL LTL) < (UCL LCL) Cp = (UTL LTL) / (UCL LCL) < 1
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MOS 3330: SPC
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187
188
TOTAL QUALITY MANAGEMENT (TQM)
Learning Objectives:
1. What is TQM
2. Quality evolution and quality gurus
3. Similarities/differences to other concepts
4. Implementation issues
5. Six sigma quality program
6. Quality awards
7. ISO
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1. What is TQM?
An organization-wide effort to achieve high product quality based
on 3 guiding principles:
1) Customer focus
Quality from the customer perspective; obtain customer feedback
2) Continual improvement
Constantly seek to improve processes, products, productivity,
effectiveness, responsiveness, etc.
3) Total participation and teamwork
Workers are the inspectors: provide training, authority, rewards
Cross-functional, process improvement teams
Top management commitment
Supplier relationship
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1.1 Stages of QM
1) Quality Inspection
2) Quality Control
Management commitment
Customer focus
Obtain management support
Choose a SPC leader
Select a process for pilot study
Empowered workers
Provide SPC training
Continual improvement
Process improvement
Construct control charts
3) Quality Assurance
Project-by-project
Process-by-process
Cross-functional
Supplier relationship
MOS 3330: TQM
4) TQM
Company-wide
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191
1.2 Quality Evolution
Ideas
Industrial
Revolution/
early 1900s
Quality
inspection
1920s1950s
Quality
control
Shewhart
Process improvement
Statistical methods
1960s1970s
Quality
assurance
Deming, Juran,
Crosby
ISO, JIT, Oil Crisis,
Foreign competition
Management philosophy
Continual improvement
Cost of quality
Zero defects
Feigenbaum
Ishikawa
Organizational focus
Customer driven quality
More choices and info
Higher expectations
Affordable quality
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192
1980s to
present
192
Events/People
TQM
1.3 Quality Gurus
Shewhart
Promoted SPC, Shewhart Cycle
Deming
Deming Wheel, 14-point quality management philosophy, promoted
quality management in Japan Deming Prize
Juran
Quality Control Handbook (famous book), quality trilogy (planning,
control and improvement), cost of quality
Crosby
Cost of poor quality, zero defects, Quality Is Free (famous book)
Feigenbaum, Ishikawa (cause-and-effect diagram)
Total quality control, company-wide commitment
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193
1.4 TQM vs. JIT
Customer focus
JIT: to achieve good forecast of customer demand
Continuous improvement (“kaizen”)
JIT: require high quality products; undercapacity scheduling
Total participation and teamwork
JIT: well-trained, multifunctional, empowered employees; group
TQM
JIT
1950 1960 1970 1980
Recognition in the West
Recognition in Japan
problem solving
JIT
1950 1960 1970 1980
1990
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TQM
1990
194
1.5 TQM Implementation Issues
Lack of a genuine quality culture
Forgetting customer-focus
Conflict with existing systems (e.g., compensation and promotion
systems, policies and procedures)
Lack of top management support and commitment
Forgetting long-term benefits (“bottom line” approach)
Inadequate training
Over- or under-reliance on quality tools
Over-emphasis on teams
Under-emphasis on individual efforts
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195
2. Six Sigma Quality Program
Six sigma: A high level of product quality with 3.4 defective
parts per million
Coined by Motorola in 1986
Motorola won Baldrige Award in 1988
Six sigma program: A quality management program with
clear business goals, which are achieved by
Cutting poor quality costs
Rewarding employees for quality improvement
Training employees Six sigma black belt certification
Black belt: Employee trained and experienced in application of statistical
techniques, problem solving, project management, team leadership skills
Applying a scientific methodology DMAIC, statistics, computers
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196
Six Sigma Methodology
DMAIC model
Define problem/opportunity
Measure characteristics that are critical-to-quality
Analyze the problem using benchmarking and gap studies
Improve by reducing variation and reducing defects
Control performance
Other tools
Computer simulation
Part standardization
Supplier qualification, SPC
Design of experiments
Measurement system analysis
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3. Quality Awards
Baldrige Award (USA): created by law in 1987
Manufacturing, service, small business, education, health care
Customer focus, process management, leadership, HR, strategic
planning, information and analysis, business results
Application, initial screening, in-depth examination
Deming Prize (Japan): created in 1951
Company, business unit, individual
Allowed foreign companies to apply in 1984
Minimum application standards
Common themes
Privilege, worthy experience, expensive
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4. Quality Standards
ISO (International Organization for Standardization)
Headquarter in Geneva, officially established in 1947
Network of national standards institutes of 146 countries
Developed over 18,000 international standards on a variety of
subjects
Quality Management ISO 9000 series
First published in 1987
To promote a uniform quality standard for cross-border transactions
A guideline for developing an organizational system for documenting
quality management-related processes and procedures
Certification of organizations, not products
Common themes: Marketing strategy, customer requirement,
international trade requirement
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ISO 9000 series include:
ISO 9000 – Quality management systems: fundamentals/ vocabulary
ISO 9001 – Quality management systems: requirements
ISO 9004 – Quality management systems: managing for the
sustained success of an organization (continuous improvement)
ISO 14000 series include:
ISO 14001 – Environmental management systems: framework /
criteria
ISO 14006 – Environmental management systems: guidelines for
incorporating ecodesign
ISO 14020 – Environmental labels and declarations
ISO 14034 – Environmental technology verification: how to verify the
performance of new environmental technologies
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ISO 9000
Registration process
Application documentation review pre-assessment
registration audit registration decision surveillance audit
Cost
Internal: analysis, project planning, system development, system
documentation, system implementation, training, internal audit,
system modifications
External: ISO publication and software, registrars (fees&travel),
consultants (fees&travel)
Time: “3 months to 3 years”
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