Lesson 1 – Introduction to Systems Thinking IE2141 Systems Thinking and Dynamics Dr. LI Haobin Senior Lecturer Department of Industrial Systems Engineering and Management (ISEM) College of Design and Engineering National University of Singapore IE2141 Systems Thinking and Dynamics – Dr. Li Haobin, National University of Singapore 1 Why to Learn Systems Thinking? Example of urban transportation in mega cities IE2141 Systems Thinking and Dynamics – Dr. Li Haobin, National University of Singapore 2 Why to Learn Systems Thinking? Various roles of Designers and Engineers IE2141 Systems Thinking and Dynamics – Dr. Li Haobin, National University of Singapore 3 Why to Learn Systems Thinking? Interdisciplinary consideration IE2141 Systems Thinking and Dynamics – Dr. Li Haobin, National University of Singapore 4 Why to Learn Systems Thinking? System problems, E.g. How effective is the odd-even restriction policy? Car plate bidding or lottery, which is better? Car Plate Lottery IE2141 Systems Thinking and Dynamics – Dr. Li Haobin, National University of Singapore Bidding 5 Why to Learn Systems Thinking? Consideration of stakeholders with different levels of perspectives, E.g. Should the government restrict car ownership, if the car manufacturers are the major industry and taxpayers? Car ownership vs. road usage, who is bearing the cost? IE2141 Systems Thinking and Dynamics – Dr. Li Haobin, National University of Singapore 6 Why to Learn Systems Thinking? Good system solutions, E.g. COE with validity period, road and fuel tax, ERP Well designed road network Shared parking facility Subsidised public transit IE2141 Systems Thinking and Dynamics – Dr. Li Haobin, National University of Singapore 7 Why to Learn Systems Thinking? As Engineers, How shall we design a good system? How to design a product that helps to build the good system? Alternatively, how to design a product that can fit well into the dynamics of the system? To achieve this, you will need to Lean to think from the system perspectives, and Master tools to understand and analyse system dynamics IE2141 Systems Thinking and Dynamics – Dr. Li Haobin, National University of Singapore 8 1st Law of System Thinking Today’s problems come from yesterday’s “solution”. Often we are puzzled by the causes of our problems, when we merely need to look at our own solutions to other problems in the past. Solutions that shift problems from one part of a system to another often go undetected because, those who "solved" the first problem are different from those who inherit the new problem. IE2141 Systems Thinking and Dynamics – Dr. Li Haobin, National University of Singapore 9 2nd Law of Systems Thinking The harder you push, the harder the system pushes back. The phenomenon of "Compensating feedback": when well-intentioned interventions call forth responses from the system that offset the benefits of the intervention. The more effort you expend trying to improve matters, the more effort seems to be required, either through an increasingly aggressive intervention or through increasingly stressful withholding of natural instincts. Yet, as individuals and organizations, we not only get drawn into compensating feedback, we often glorify the suffering that ensues. IE2141 Systems Thinking and Dynamics – Dr. Li Haobin, National University of Singapore 10 3rd Law of Systems Thinking Behaviour grows better before it grows worse. The better before worse response to many management interventions is what makes decision making counterproductive, in the situations where factors other than the intrinsic merits of alternative courses of action weigh in making decisions – factors such as building one's own power base, or "looking good," or "pleasing the boss.“ In complex human systems there are always many ways to make things look better in the short run. Only eventually does the compensating feedback come back to haunt you. IE2141 Systems Thinking and Dynamics – Dr. Li Haobin, National University of Singapore 11 4th Law of Systems Thinking The easy way out usually leads back in. We all find comfort applying familiar solutions to problems, sticking to what we know best. Very often, the keys are off in the darkness. After all, if the solution were easy to see or obvious to everyone, it probably would already have been found. Pushing harder and harder on familiar solutions, while fundamental problems persist or worsen, is a reliable indicator of nonsystemic thinking – what we often call the "what we need here is a bigger hammer" syndrome. IE2141 Systems Thinking and Dynamics – Dr. Li Haobin, National University of Singapore 12 5th Law of Systems Thinking The cure can be worse than the disease. Sometimes the easy or familiar solution is not only ineffective, but addictive and dangerous. The long-term, most insidious consequence of applying nonsystemic solutions is increased need for more and more of the solution. The phenomenon is called "Shifting the Burden to the Intervenor.“ Instead, any long-term solution must, strengthen the ability of the system to shoulder its own burdens. Sometimes that is difficult; other times it is surprisingly easy. IE2141 Systems Thinking and Dynamics – Dr. Li Haobin, National University of Singapore 13 6th Law of Systems Thinking Faster is slower. Virtually all natural systems, from ecosystems to animals to organizations, have intrinsically optimal rates of growth. The optimal rate is far less than the fastest possible growth. When growth becomes excessive, as it does in cancer, the system itself will seek to compensate by slowing down; perhaps putting the organization's survival at risk in the process. IE2141 Systems Thinking and Dynamics – Dr. Li Haobin, National University of Singapore 14 7th Law of Systems Thinking Cause and effect are not closely related in time and space. “Effects" means the obvious symptoms that indicate that there are problems. “Cause" means the interaction of the underlying system that is most responsible for generating the symptoms, and it could lead to changes producing lasting improvement. A fundamental characteristic of complex human systems: "cause" and "effect" are not close in time and space. However, most of us assume, most of the time, that cause and effect are close in time and space. There is a fundamental mismatch between the nature of reality in complex systems and our predominant ways of thinking about that reality. IE2141 Systems Thinking and Dynamics – Dr. Li Haobin, National University of Singapore 15 8th Law of Systems Thinking Small changes can produce big results, but the areas of highest leverage are often the least obvious. Some have called systems thinking the “new dismal science” because it teaches that most obvious solutions don't work – at best, they improve matters in the short run, only to make things worse in the long run. But there is another side to the story. For systems thinking also shows that small, well-focused actions can sometimes produce significant, enduring improvements, if they're in the right place. Systems thinkers refer to this principle as “leverage”. IE2141 Systems Thinking and Dynamics – Dr. Li Haobin, National University of Singapore 16 9th Law of Systems Thinking You can have your cake and eat it too – but not at once. Sometimes, the knottiest dilemmas, when seen from the systems point of view, aren't dilemmas at all. They are artifacts of "snapshot" rather than "process" thinking, and appear in a whole new light once you think consciously of change over time. IE2141 Systems Thinking and Dynamics – Dr. Li Haobin, National University of Singapore 17 10th Law of Systems Thinking Dividing an elephant in half does not produce two small elephants. Living systems have integrity. Their character depends on the whole. The same is true for organizations; to understand the most challenging managerial issues requires seeing the whole system that generates the issues. Incidentally, sometimes people go ahead and divide an elephant in half anyway. It results in a complicated problem where there is no leverage to be found because the leverage lies in interactions that cannot be seen from looking only at the piece you are holding. IE2141 Systems Thinking and Dynamics – Dr. Li Haobin, National University of Singapore 18 11th Law of Systems Thinking There is no blame. We tend to blame outside circumstances for our problems. “Someone else” – the competitors, the press, the changing mood of the marketplace, the government – did it to us. Systems thinking shows us that there is no outside; that you and the cause of your problems are part of a single system. The cure lies in your relationship with your “enemy”. IE2141 Systems Thinking and Dynamics – Dr. Li Haobin, National University of Singapore 19 What is a System? A system is a group of interacting or interrelated elements that act according to a set of rules to form a unified whole. A system, surrounded and influenced by its environment, is described by its boundaries, structure and purpose and expressed in its functioning. Source: Alexander Backlund (2000). "The definition of system". In: Kybernetes Vol. 29 nr. 4, pp. 444–451. IE2141 Systems Thinking and Dynamics – Dr. Li Haobin, National University of Singapore 20 How to Define a System? Elements / Parts Interaction / Interrelation / Structure Boundaries / Environment Purpose / Functions Elements / Parts Boundaries Input / Output Input (Dependency on Environment) Output (Purpose / Functions) Interaction / Interrelation / Structure IE2141 Systems Thinking and Dynamics – Dr. Li Haobin, National University of Singapore 21 Examples of Systems Human Body Systems IE2141 Systems Thinking and Dynamics – Dr. Li Haobin, National University of Singapore 22 Examples of Systems Computer Systems Software System IE2141 Systems Thinking and Dynamics – Dr. Li Haobin, National University of Singapore Hardware System 23 Examples of Systems Industrial Systems Container Port System IE2141 Systems Thinking and Dynamics – Dr. Li Haobin, National University of Singapore Warehouse System 24 Examples of Systems Natural / Technological Eco-Systems IE2141 Systems Thinking and Dynamics – Dr. Li Haobin, National University of Singapore 25 Examples of Systems Social Systems IE2141 Systems Thinking and Dynamics – Dr. Li Haobin, National University of Singapore 26 Systems vs. Collections Collection is a set of items or amount of material procured or gathered together while system is a collection of “organized” things Elements / Parts Boundaries Input (Dependency on Environment) Interaction / Interrelation / Structure IE2141 Systems Thinking and Dynamics – Dr. Li Haobin, National University of Singapore Elements / Parts Boundaries Output (Purpose / Functions) System Collection 27 Systems vs. Collections Collection is a set of items or amount of material procured or gathered together while system is a collection of “organized” things Examples of Collections: IE2141 Systems Thinking and Dynamics – Dr. Li Haobin, National University of Singapore 28 Environment / External Boundaries PESTLE Political Economic / Financial Elements / Parts Socio-Cultural / Societal Boundaries Technological Legal Environmental Input (Dependency on Environment) Output (Purpose / Functions) Interaction / Interrelation / Structure IE2141 Systems Thinking and Dynamics – Dr. Li Haobin, National University of Singapore 29 Environment / External Boundaries Political Factors relate to the pressures brought by political institutions Elections and political trends Internal political issues Inter country relationships Local commissioning processes Corruption, Bureaucracy Wars, terrorism and conflicts Government policies Lobbying and pressure groups IE2141 Systems Thinking and Dynamics – Dr. Li Haobin, National University of Singapore 30 Environment / External Boundaries Economic Factors relate to economic policies and structures Local economy Taxation, inflation, interest Economy trends seasonality issues Industry growth Import / export ratios International trade International exchange rates IE2141 Systems Thinking and Dynamics – Dr. Li Haobin, National University of Singapore 31 Environment / External Boundaries Social Factors relate to the cultural aspects that affect the demand of products and how business operates Demographics Media views of the industry Work ethic Brand, company, technology image Lifestyle trends Consumer buying patterns Ethical issues Advertising and publicity IE2141 Systems Thinking and Dynamics – Dr. Li Haobin, National University of Singapore 32 Environment / External Boundaries Technological Factors relate to the technological aspects, innovations, barriers and incentives Emerging technologies Maturity of technology Technology legislation Research and Innovation Information and communications Competitor technology development Intellectual property issues IE2141 Systems Thinking and Dynamics – Dr. Li Haobin, National University of Singapore 33 Environment / External Boundaries Legal Factors relate to the laws, regulation and legislation that will affect the way businesses operate Current legislation International legislation Employment law Consumer protection Health and safety regulations Tax regulations Competitive regulations Industry specific regulations IE2141 Systems Thinking and Dynamics – Dr. Li Haobin, National University of Singapore 34 Environment / External Boundaries Environmental Factors relate to the aspects of climate and natural environment Environmental regulations Ecological regulations Reduction of carbon footprint Sustainability Impact of adverse weather IE2141 Systems Thinking and Dynamics – Dr. Li Haobin, National University of Singapore 35 Classification of Systems Classification by system characteristics Static vs. Dynamic Systems Causal vs. Non-Causal Systems Time-Variant vs. Time-Invariant Systems Linear vs. Non-Linear Systems Invertible vs. Non-Invertible Systems Stable vs. Unstable Systems IE2141 Systems Thinking and Dynamics – Dr. Li Haobin, National University of Singapore 36 Static vs. Dynamic Systems Static System – output of system depends only on present values of input Memoryless system Dynamic System – output of system depends on past or future values of input at any instant of time System with memory 𝑋𝑋 𝑡𝑡 − 𝛿𝛿 𝑋𝑋 𝑡𝑡 𝑋𝑋 𝑡𝑡 + 𝛿𝛿 Example of static systems: 𝑌𝑌 𝑡𝑡 = 𝑋𝑋 𝑡𝑡 + 3, 𝑌𝑌 𝑡𝑡 = 2𝑋𝑋 𝑡𝑡 SYSTEM IE2141 Systems Thinking and Dynamics – Dr. Li Haobin, National University of Singapore 𝑌𝑌 𝑡𝑡 Example of dynamic systems: 𝑌𝑌 𝑡𝑡 = 𝑋𝑋 𝑡𝑡 − 1 , 𝑌𝑌 𝑡𝑡 = 3𝑋𝑋 𝑡𝑡 + 2 , 𝑌𝑌 𝑡𝑡 = 𝑋𝑋 𝑡𝑡 + 2𝑋𝑋 𝑡𝑡 − 1 37 Static vs. Dynamic Systems Examples Static systems – furniture, dishes, buildings, bridges, fix deposit, onetime investment (simplification, approximation or abstraction of real-world dynamic systems) Dynamic systems – human body, computer, machinery, car, property, trading strategy IE2141 Systems Thinking and Dynamics – Dr. Li Haobin, National University of Singapore 38 Causal vs. Non-Causal Systems Causal System – output of system is independent of future values of input All real-life system, all practical or physically realizable systems are causal systems Non-Causal System – output of system depends on future values of input at any instant of time Anti-causal system – output of system only depends on future values of the input Example of cause systems: 𝑋𝑋 𝑡𝑡 − 𝛿𝛿 𝑋𝑋 𝑡𝑡 𝑋𝑋 𝑡𝑡 + 𝛿𝛿 SYSTEM IE2141 Systems Thinking and Dynamics – Dr. Li Haobin, National University of Singapore 𝑌𝑌 𝑡𝑡 𝑌𝑌 𝑡𝑡 = 𝑋𝑋 𝑡𝑡 + 3, 𝑌𝑌 𝑡𝑡 = 2𝑋𝑋 𝑡𝑡 + 𝑋𝑋 𝑡𝑡 − 1 Example of non-causal systems: 𝑌𝑌 𝑡𝑡 = 𝑋𝑋 𝑡𝑡 − 1 + 2𝑋𝑋 𝑡𝑡 + 3𝑋𝑋 𝑡𝑡 + 2 Example of anti-causal systems: 𝑌𝑌 𝑡𝑡 = 2𝑋𝑋 𝑡𝑡 + 1 39 Causal vs. Non-Causal Systems Examples Causal systems – furniture, dishes, buildings, bridges, fix deposit, one-time investment, human body, computer, machinery, car, property, trading strategy Non-causal systems – an ideal predictive maintenance system, a perfect just-in-time system (not practical or implementable in real-life) Just-In-Time IE2141 Systems Thinking and Dynamics – Dr. Li Haobin, National University of Singapore Predictive Maintenance 40 Time-Variant vs. Time-Invariant Systems Time-Variant (TV) System – a system whose output response depends on moment of observation as well as moment of input signal application. In other words, a time delay or time advance of input not only shifts the output signal in time but also changes other parameters and behavior. Time variant systems respond differently to the same input at different times. Time-Invariant (TIV) System – a system where the opposite is true for. 𝑋𝑋 𝑡𝑡 SYSTEM 𝑌𝑌 𝑡𝑡 Delay by 𝑡𝑡0 IE2141 Systems Thinking and Dynamics – Dr. Li Haobin, National University of Singapore Delay by 𝑡𝑡0 𝑋𝑋 ′ 𝑡𝑡 = 𝑋𝑋 𝑡𝑡 − 𝑡𝑡0 𝑌𝑌 ′ 𝑡𝑡 = 𝑌𝑌 𝑡𝑡 − 𝑡𝑡0 SYSTEM 𝑌𝑌 ′′ 𝑡𝑡 ≠ 𝑌𝑌 ′ 𝑡𝑡 𝑌𝑌 ′′ 𝑡𝑡 = 𝑌𝑌 ′ 𝑡𝑡 41 Time-Variant vs. Time-Invariant Systems Examples Time-variant (TV) systems – investment in stocks Time-invariant (TIV) systems – investment in CPF Accounts (TIV systems are relative in real-life, e.g., reaching age of 55) IE2141 Systems Thinking and Dynamics – Dr. Li Haobin, National University of Singapore 42 Linear vs. Non-Linear Systems Linear System – a system which follows the principle of superposition Law of Additivity + Law of Homogeneity Non-Linear System – a system for which the principle of superposition is violated. 𝑋𝑋1 𝑡𝑡 ∑ 𝑋𝑋2 𝑡𝑡 SYSTEM 𝑋𝑋1 𝑡𝑡 + 𝑋𝑋2 𝑡𝑡 𝑌𝑌1 𝑡𝑡 SYSTEM SYSTEM IE2141 Systems Thinking and Dynamics – Dr. Li Haobin, National University of Singapore 𝑌𝑌2 𝑡𝑡 𝑌𝑌 ′′ 𝑡𝑡 = 𝑌𝑌 ′ 𝑡𝑡 𝑌𝑌 ′′ 𝑡𝑡 ≠ 𝑌𝑌 ′ 𝑡𝑡 ∑ 𝑌𝑌 ′ = 𝑌𝑌1 𝑡𝑡 + 𝑌𝑌2 𝑡𝑡 Law of Additivity 43 Linear vs. Non-Linear Systems Linear System – a system which follows the principle of superposition Law of Additivity + Law of Homogeneity Non-Linear System – a system for which the principle of superposition is violated. 𝑋𝑋 𝑡𝑡 SYSTEM 𝑘𝑘 𝑘𝑘𝑘𝑘 𝑡𝑡 IE2141 Systems Thinking and Dynamics – Dr. Li Haobin, National University of Singapore 𝑌𝑌 𝑡𝑡 SYSTEM 𝑘𝑘 𝑌𝑌 ′ = 𝑘𝑘𝑘𝑘 𝑡𝑡 𝑌𝑌 ′′ 𝑡𝑡 = 𝑌𝑌 ′ 𝑡𝑡 𝑌𝑌 ′′ 𝑡𝑡 ≠ 𝑌𝑌 ′ 𝑡𝑡 Law of Homogeneity 44 Linear vs. Non-Linear Systems Examples Linear systems – pricing for groceries at FairPrice, total time spent by a crowd watching a movie Non-linear systems – pricing for stocks at SGX, total time spent by a crowd queueing for a restaurant (real-life systems are difficult to control as many of them are non-linear) IE2141 Systems Thinking and Dynamics – Dr. Li Haobin, National University of Singapore 45 Invertible vs. Non-Invertible Systems For an invertible system, there should be one to one mapping between input and output at each and every instant of time One to one mapping 1 𝑎𝑎 2 3 𝑐𝑐 6 𝑏𝑏 2 𝑋𝑋 𝑡𝑡 Many to one mapping SYSTEM IE2141 Systems Thinking and Dynamics – Dr. Li Haobin, National University of Singapore 𝑎𝑎 4 𝑌𝑌 𝑡𝑡 𝑋𝑋 𝑡𝑡 𝑏𝑏 SYSTEM 𝑌𝑌 𝑡𝑡 46 Invertible vs. Non-Invertible Systems For an invertible system, there should be one to one mapping between input and output at each and every instant of time 𝑋𝑋 𝑡𝑡 Invertible System IE2141 Systems Thinking and Dynamics – Dr. Li Haobin, National University of Singapore 𝑌𝑌 𝑡𝑡 Inverse System 𝑌𝑌 ′ 𝑡𝑡 = 𝑋𝑋 𝑡𝑡 ± 𝛿𝛿 𝑌𝑌 ′ 𝑡𝑡 ≠ 𝑋𝑋 𝑡𝑡 ± 𝛿𝛿 47 Invertible vs. Non-Invertible Systems Examples Invertible systems – identifying a person by his/her IC, knowing a person by his/her spouse, sending emails by an internet user Non-invertible systems – paying bills, scoring in an exam, sending emails by a hacker (real-life systems are complex as many of them are non-invertible) IE2141 Systems Thinking and Dynamics – Dr. Li Haobin, National University of Singapore 48 Stable vs. Unstable Systems For a stable system, output should be bounded for bounded input (BIBO) at each and every instant of time 𝑋𝑋 𝑡𝑡 𝑋𝑋 𝑡𝑡 ∈ 𝐿𝐿𝑋𝑋 , 𝑈𝑈 𝑋𝑋 IE2141 Systems Thinking and Dynamics – Dr. Li Haobin, National University of Singapore SYSTEM 𝑌𝑌 𝑡𝑡 𝑌𝑌 𝑡𝑡 ± 𝛿𝛿 ∈ 𝐿𝐿𝑌𝑌 , 𝑈𝑈 𝑌𝑌 𝑌𝑌 𝑡𝑡 ± 𝛿𝛿 ∈ −∞, ∞ 49 Stable vs. Unstable Systems Examples Stable systems – market of iPhone 13, restaurant, public transit Unstable systems – climate change, financial crisis (unstable systems are relative, as the output can be always bounded under a larger system, however it is beyond our control or not in favor) IE2141 Systems Thinking and Dynamics – Dr. Li Haobin, National University of Singapore 50 Feedback and Control Systems A control system possessing monitoring feedback, the deviation signal formed as a result of this feedback being used to control the action of a final control element in such a way as to tend to reduce the deviation to zero (Mayr, Otto 1970). Parent System Environment 𝑋𝑋 ′ 𝑡𝑡 Goal Deviation (Discrepancy) Controller Perceived State IE2141 Systems Thinking and Dynamics – Dr. Li Haobin, National University of Singapore Action (Decision) 𝑋𝑋 𝑡𝑡 Observer Sub-System System 𝑌𝑌 𝑡𝑡 𝑌𝑌 ′ 𝑡𝑡 Feedback 51 Feedback and Control Systems Example – Air-Con System Room Air-Con Environment (outdoor temperature) 𝑋𝑋 ′ 𝑡𝑡 Goal (specific room temperature) Deviation (temperature difference) IC Chip Perceived State (sensible temperature) IE2141 Systems Thinking and Dynamics – Dr. Li Haobin, National University of Singapore Action (electricity/ power) 𝑋𝑋 𝑡𝑡 Sensor Compressor System 𝑌𝑌 𝑡𝑡 (cool air) 𝑌𝑌 ′ 𝑡𝑡 Feedback (room temperature) 52 Coupling of Sub-Systems A coupled system consists of sub-systems, including control systems, connected in series or in parallel S6 S5 C2 C1 S1 S4 S2 S7 S3 O1 O2 IE2141 Systems Thinking and Dynamics – Dr. Li Haobin, National University of Singapore 53 Coupling of Sub-Systems A Controller or Observer in a control system can also be seen as a sub-system S6 S5 S11 S9 S1 S4 S2 S7 S3 S8 S10 IE2141 Systems Thinking and Dynamics – Dr. Li Haobin, National University of Singapore 54 Hierarchical Structure of Systems The composition of coupled systems are usually represented in the hierarchical structure System S6, S7 S5, S10, S11 S4, S8, S9 S6 S5 S1 S4 S2 S8 S3 S10 S9 S7 S11 S1, S2, S3 IE2141 Systems Thinking and Dynamics – Dr. Li Haobin, National University of Singapore 55 Methodologies of Systems Thinking 1. Identifying a system Elements, boundaries, sub-systems Environment, purpose, input and output Stakeholders (controllers), i.e., who are making decisions and influencing the sub-systems Perceptions (observers), i.e., how the information from feedbacks of sub-systems are perceived IE2141 Systems Thinking and Dynamics – Dr. Li Haobin, National University of Singapore 56 Methodologies of Systems Thinking 2. Understanding a system Understanding how the system works, its interconnections and behaviors Classification of the system / sub-systems Level of perspectives Behavior over time Causal loop diagrams (CLD) System archetypes IE2141 Systems Thinking and Dynamics – Dr. Li Haobin, National University of Singapore 57 Methodologies of Systems Thinking 3. Predicting system behavior Forecast how the system will behavior in future System dynamics simulation Stock-flow diagrams (SFD) Modelling time delays Data collection and estimation Verification and validation IE2141 Systems Thinking and Dynamics – Dr. Li Haobin, National University of Singapore 58 Methodologies of Systems Thinking 4. Devising improvements How can we modify the system to produce desired results? Modelling of decision-making structure Identifying leverage points Decision analysis methodologies Optimization of decision parameters IE2141 Systems Thinking and Dynamics – Dr. Li Haobin, National University of Singapore 59 THANK YOU IE2141 Systems Thinking and Dynamics – Dr. Li Haobin, National University of Singapore 60