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lecture 1 : introduction. This lecture tries to answer the following questions: how different is IE from other engineering disciplines and from management? what is the relationship between IE, OR and MANAGEMENT SCIENCE ? what is IE work about? who needs SYSTEMS THINKING and why? - PowerPoint PPT Presentation
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Spring 2010 - ÇG IE 398 - lecture 1 1
lecture 1 : introductionThis lecture tries to answer the following questions:
•how different is IE from other engineering disciplines and from management?
•what is the relationship between IE, OR and MANAGEMENT SCIENCE ?
•what is IE work about?•who needs SYSTEMS THINKING and why?
•what is SYSTEMS THINKING anyway?
Spring 2010 - ÇG IE 398 - lecture 1 2
what is IE work about?• IE seeks to improve organised human activity• organised human activity takes place in what we
can perceive as organisations or human activity systems
• human activity systems are social systems in the first place
• all engineering work has a social context, but systems that non-IE engineers work with are mostly perceived as technical systems
• technical systems are embedded in almost all human activity systems
• for this reason, human activity systems can also be called socio-technical systems
Spring 2010 - ÇG IE 398 - lecture 1 3
how different is IE ?• engineers are concerned with goal seeking
systems that are primarily closed• this means that there is a goal the system
wants to achieve• such systems can be put into a laboratory
and studied in isolation from the environment
• the system can thus be reduced to its parts and analysed
• analysis can provide knowledge and understanding of a closed system
Spring 2010 - ÇG IE 398 - lecture 1 4
• IE is concerned with purposeful systems that are always open
• a purposeful system is an organisation with goal seeking individuals
• these goals can change from person to person and also from time to time
• open systems do not fit into laboratories
• understanding an open system will not be possible through analysis only
Spring 2010 - ÇG IE 398 - lecture 1 5
• analysis of a system reveals its structure and how it works; its product is knowledge, not understanding
• we need systems thinking to understand human activity systems
• systems thinking includes and complements analysis
• this is how OR/IE is different from most engineering and from “disciplinary” science
Spring 2010 - ÇG IE 398 - lecture 1 6
IE – OR – MS • OR provides the “scientific” basis of IE• the mathematical models and
techniques used by IE are primarily OR models and techniques
• in the past, IE was more concerned with the engineering applications of OR
• IE now deals with almost all applications of OR, alongside traditional engineering
• MS is another term for OR
Spring 2010 - ÇG IE 398 - lecture 1 7
who needs systems thinking ?As we already said before, IE learning
has dual objectives:• mastering quantitative analysis
and mathematical modelling (OR, probability theory, statistics, economics etc)
• building systems thinking skills in order to put this knowledge into effective use
Spring 2010 - ÇG IE 398 - lecture 1 8
what is systems thinking ?five real-life examples that need ST:1. an emergency services call centre• answering, recording and checking
calls• providing fast response• balancing costs and waiting times• difficulty in evaluating response rate a queueing, or waiting line problem
Spring 2010 - ÇG IE 398 - lecture 1 9
2. vehicle scheduling• varying pick-up/delivery times• “time-windows”• labour rules• capacity and congestion
restrictions• 20! = 2 432 902 000 000 000
000least time, least distance, least
cost ?
Spring 2010 - ÇG IE 398 - lecture 1 10
3. writing a mission statement• should be relevant and
meaningful• achievable and measurable
goals and targets• active cooperation and
participation must be secured• often a compromise• lengthy canvassing and
negotiations neededsoft OR; problem structuring
Spring 2010 - ÇG IE 398 - lecture 1 11
4. the “Deep Cove” project• an environmentally responsible economic
project to transport tail race water• no permanent residence in the sound,
reduced tanker speed, rubbish removal etc.
• but there will be other ecological risks:− increased salination− faster mixing of fresh and salt water− risk of spills− risk of introducing pests and poaching− etc.
conflicting objectives, MCDM
Spring 2010 - ÇG IE 398 - lecture 1 12
5. screening for breast cancer• early tretment of growths • incidence rises with age• 95% chance of cure if detected at
preinvasive phase• mammography effective 85% of the
time• costs $200 000-$300 000 per machine;
$50-$100 per screening etc.what is the best screening policy ?how do we balance costs and human
suffering ?
Spring 2010 - ÇG IE 398 - lecture 1 13
common features of these situations:– a complex problem situation
• what is the problem? • what do we mean by a solution?
– incomplete information– situation conceived as a system;
meaning that a system is,• not an ontological entity (ontology is an
area of metaphysics that studies the nature and existence of reality)
• but it is an epistemological entity (epistemology is an area of metaphysics that studies the nature of knowledge about reality)
Spring 2010 - ÇG IE 398 - lecture 1 14
– situation requires systems thinking such as:•hard OR, or•soft OR
– all these situations involve gaining knowledge about a human activity system and all such knowledge is heavily meaning loaded and experience based
– knowledge is gained in what Checkland (1) calls the experience – action cycle:
Spring 2010 - ÇG IE 398 - lecture 1 15
Spring 2010 - ÇG IE 398 - lecture 1 16
“systems thinking is to formulate some systems relevant to aspects of perceived reality that is of interest and then to use the systems in a methodology to find out about, or gain insight to, or engineer some of the world outside”the following figure from Checkland (1) summarises the difference between the two perspectives:
------------------------------------------------------------------(1) Checkland P.,J. Scoles Soft Systems Methodology in Action, Wiley 1990
Spring 2010 - ÇG IE 398 - lecture 1 17