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-
- Type:
- Document
- Date Created:
- 1992
- Collection:
- System Dynamic Society Records
- Collecting Area:
- University Archives
- Collection ID:
- ua435
- Parent Record(s):
- 23d738ba88f8333bc39725f9cb5bd0b8, 68f8be4710ef70435fee8d3c8bf4c1f7, and c1647c2958efc6aa1703a2b3e2d5c65f
- Description:
- Studies of chaos in foreign exchange markets often lack a theoretical underpinning. This paper tries to give some reasons why exchange rate movements may become chaotic. Starting from an assumption about different groups of traders that goes beyond recent models of fundamentalists’ and chartists’ behaviour it argues that, to capture the idea of chaos, foreign exchange markets have to be modelled as a dissipative system and not, as usual, as a closed conservative one. A qualitative system dynamics approach is chosen to demonstrate the complex interaction processes arising.
-
- Type:
- Document
- Date Created:
- 1992
- Collection:
- System Dynamic Society Records
- Collecting Area:
- University Archives
- Collection ID:
- ua435
- Parent Record(s):
- 23d738ba88f8333bc39725f9cb5bd0b8, 68f8be4710ef70435fee8d3c8bf4c1f7, and c1647c2958efc6aa1703a2b3e2d5c65f
- Description:
- Ongoing research in the Rockefeller College of Public Affairs and policy is focusing on strategies for efficient and effective model building in groups. The intent is to involve a relatively large client group in the business of model formulation, not just conceptualization. Recent projects have explored strategies for accelerated group model building in the context of two public policy problem areas: the burgeoning cost and caseload of foster care in New York State, and recent unexplained increases in Medicaid costs in the state of Vermont.Five roles appear to be essential to support effective group model building efforts. We term the five roles the facilitator, the content coach, the process coach, the recorder, and the gatekeeper. This article identifies the five roles, briefly overviews the two problem areas, sketches the design of the group model building efforts, outlines the apparent results, and hypothesizes principles and strategies to guide future group modeling efforts.
-
- Type:
- Document
- Date Created:
- 1992
- Collection:
- System Dynamic Society Records
- Collecting Area:
- University Archives
- Collection ID:
- ua435
- Parent Record(s):
- 23d738ba88f8333bc39725f9cb5bd0b8, 68f8be4710ef70435fee8d3c8bf4c1f7, and c1647c2958efc6aa1703a2b3e2d5c65f
- Description:
- Few real life case study examples exist concerning optimisation in system dynamics models. This study reports an attempt to estimate relevant parameters of an AIDS spread model in order to check whether the chosen model structure can be separately parameterised and thereby explain the course of the epidemic for more than one country. The UK and USA are the two countries selected and the parameter values derived are reported for each. The values obtained are not inconsistent with emerging knowledge about the epidemic and the subsequent optimised projections reveal that the peak of the homosexual epidemic has been or is about to be reached in both countries.
-
- Type:
- Document
- Date Created:
- 1992
- Collection:
- System Dynamic Society Records
- Collecting Area:
- University Archives
- Collection ID:
- ua435
- Parent Record(s):
- 23d738ba88f8333bc39725f9cb5bd0b8, 68f8be4710ef70435fee8d3c8bf4c1f7, and c1647c2958efc6aa1703a2b3e2d5c65f
- Description:
- The paper describes from a client point of view some experiences with system-dynamics during the first year of Nostradamus. Nostradamus is a project, which aims at simulating the senior management of a large Dutch governmental organization with an one action orientated engeneers approach to adopt a more outwardly-orientated, creative and flexible attitude. In the beginning of the project the use of system-dynamics was intended as a central guiding aid in the proces of organizational growth. The intended use proved considerably more extensive than the actual use. Insofar this regression is attributable to system-dynamics we, as a client of system-dynamics, see in this regression a possible challenge for system-dynamics. We think system-dynamics could have been a more central supporting aid in Nostradamus if we would have found well-documented experience with system-dynamics in comparable situations. We suggest the system-dynamics-society to develop certain activities in order to stimulate demand and to better link up demand and supply in the area of systems-thinking.
-
- Type:
- Document
- Date Created:
- 1992
- Collection:
- System Dynamic Society Records
- Collecting Area:
- University Archives
- Collection ID:
- ua435
- Parent Record(s):
- 23d738ba88f8333bc39725f9cb5bd0b8, 68f8be4710ef70435fee8d3c8bf4c1f7, and c1647c2958efc6aa1703a2b3e2d5c65f
- Description:
- While nonlinear combinations of multiple modes existing in complex oscillatory systems may generate chaotic behavior in real systems, the studies of chaos attempted in system dynamics have often resorted to forcing simplistic models of systems to chaos. This paper illustrates how chaotic modes have been constructed through the creation of mis-specifications and anomalies in the model structure and parameters. This process has not only reduced the models to artifacts with little relevance to problem solving but has also invariably introduced a stiff structure that is susceptible to considerable building up error as numerical integration methods are used with long simulation times. The paper concludes that a model must qualify as an empirically valid system by meeting the requirements of the normal system dynamics practice if the chaotic modes it generates are to be of practical value.
-
- Type:
- Document
- Date Created:
- 1992
- Collection:
- System Dynamic Society Records
- Collecting Area:
- University Archives
- Collection ID:
- ua435
- Parent Record(s):
- 23d738ba88f8333bc39725f9cb5bd0b8, 68f8be4710ef70435fee8d3c8bf4c1f7, and c1647c2958efc6aa1703a2b3e2d5c65f
- Description:
- Since formal modelling requires having a model boundary encompassing finite complexity, so deductive logic is possible, complex problems must be partitioned into simpler parts before being analysed. There are many ways to slice a complex problem but not all create partitions that keep together processes contributing to effective policy design. This paper explore ways in which a complex problem may be appropriately sliced so the models of the partitions can serve as effective tools for policy design.
-
- Type:
- Document
- Date Created:
- 1992
- Collection:
- System Dynamic Society Records
- Collecting Area:
- University Archives
- Collection ID:
- ua435
- Parent Record(s):
- 23d738ba88f8333bc39725f9cb5bd0b8, 68f8be4710ef70435fee8d3c8bf4c1f7, and c1647c2958efc6aa1703a2b3e2d5c65f
- Description:
- This paper describes a case study of applying organizational learning principles to the strategic change of a large German automotive company which seems to be successful alternative to the usual top-down approaches. Different models of implementing change processes are discussed, and their adequacies are assessed regarding to the degree of supporting self-transformational processes within the organizational.
-
- Type:
- Document
- Date Created:
- 1992
- Collection:
- System Dynamic Society Records
- Collecting Area:
- University Archives
- Collection ID:
- ua435
- Parent Record(s):
- 23d738ba88f8333bc39725f9cb5bd0b8, 68f8be4710ef70435fee8d3c8bf4c1f7, and c1647c2958efc6aa1703a2b3e2d5c65f
- Description:
- To the date, Budget Plan definition in Italian public companies is approached with insufficient deepness. We believe this is common to other countries too.Indeed, most public organizations develop the Budget Plan basing themselves only upon the available data and not upon knowledge acquired in years of experience. Balance sheet data are therefore obtained simply adding to the previous information, an amount estabilished, for example, on the expected inflation rate.This approach although “trivial” supports the budget responsible, because during the budget presentation, very few elements can be effectively criticized. It is commonly accepted that also public companies find themselves in turbulent environments. This is due to both the increased number of endogenous variables, and to the complexity of exogenous parameters. Therefore the Budget Plan definition becomes always more critical, and consequential difficulty of its evaluation assumes relevant importance.The paper describes an experiment carried out by an Italian Public company which is adopting a dynamic economic- financial model for both, Budget Plan definition and for its evaluation. The model is based upon System Dynamics approach and evaluates a series of scenarios providing support to the budget definition responsibles in taking strategic policy decisions, and better “explaining” the effects of decisions undertaken.
-
- Type:
- Document
- Date Created:
- 1992
- Collection:
- System Dynamic Society Records
- Collecting Area:
- University Archives
- Collection ID:
- ua435
- Parent Record(s):
- 23d738ba88f8333bc39725f9cb5bd0b8, 68f8be4710ef70435fee8d3c8bf4c1f7, and c1647c2958efc6aa1703a2b3e2d5c65f
- Description:
- System Dynamics has not achieved widespread recognition as a paradigm of substance in the business-related disciplines of Strategic Management, Organization Behavior, Organization Theory, or Operations Management. One reason for its slow acceptance by academicians in these fields and related social sciences may lie in the specialized meanings and usages attached to common words by the System Dynamics lexicon. Words such as “open,” “closed,” “feedback,” and “structure” -- used differently than established scientists might expect --may create perceptions that System Dynamicists simply don’t understand systems theory. Writers in the field need pay special attention to the semantic implications of their presentation.
-
- Type:
- Document
- Date Created:
- 1992
- Collection:
- System Dynamic Society Records
- Collecting Area:
- University Archives
- Collection ID:
- ua435
- Parent Record(s):
- 23d738ba88f8333bc39725f9cb5bd0b8, 68f8be4710ef70435fee8d3c8bf4c1f7, and c1647c2958efc6aa1703a2b3e2d5c65f
- Description:
- Organizational learning is intrinsically systemic, because it deals with changes in thinking and acting not only in individuals, or in teams, but organization-wide. Our ability to understand and improve organizational learning will depend on having an operational systems framework, which can both sharpen theoretical insights and address practical management concerns. Building on past work in organizational learning and system dynamics, the new Center for Organizational Learning at MIT is attempting to develop a rigorous foundation of systems principles and methods so that current interest in organizational learning and “ learning organizations” can lead to significant advances in management theory and practice.
-
- Type:
- Document
- Date Created:
- 1992
- Collection:
- System Dynamic Society Records
- Collecting Area:
- University Archives
- Collection ID:
- ua435
- Parent Record(s):
- 23d738ba88f8333bc39725f9cb5bd0b8, 68f8be4710ef70435fee8d3c8bf4c1f7, and c1647c2958efc6aa1703a2b3e2d5c65f
- Description:
- We gave a report on the model for dental diseases at the 1987 System Dynamics Conference. The model consists of 4 sectors: demography, cavities, pyorrhea and baby teeth. The demographic sector covered population of 5 three-year age groups under 14 years of age and 13 five-year age groups above 15 years of age. The cavities sectors and pyorrhea sector were composed of population of five-years age groups, on the other hand, the baby teeth sector used population of three-year age groups.From the total number of defective teeth, total dental costs in Japan were calculated annually from 1963 and projected to 2025. We added to this model a new level variable which is technology (rate variables and multipliers) in order to demonstrate to the effect of technology on the other level variables. New simulation results will be reported at the International System Dynamics Conference this year.
-
- Type:
- Document
- Date Created:
- 1992
- Collection:
- System Dynamic Society Records
- Collecting Area:
- University Archives
- Collection ID:
- ua435
- Parent Record(s):
- 23d738ba88f8333bc39725f9cb5bd0b8, 68f8be4710ef70435fee8d3c8bf4c1f7, and c1647c2958efc6aa1703a2b3e2d5c65f
- Description:
- This paper explores the advantages of System Dynamics as an enquiry method for analysis of blood bank management Systems which exhibit far reaching social implications. Causal loop diagrams are developed connecting various system components. The integration of individual causal loops is presented in the form of an influence diagram representing the ‘dynamics’ of a blood bank. Simulation model is built on the basis of causal loop diagrams. The system response exogenous disturbances or policy changes are analyzed. The catastrophe model of blood bank system is developed and the parameters forming the control surface and behaviour surface are correlated with those of the System Dynamics model.
-
- Type:
- Document
- Date Created:
- 1992
- Collection:
- System Dynamic Society Records
- Collecting Area:
- University Archives
- Collection ID:
- ua435
- Parent Record(s):
- 23d738ba88f8333bc39725f9cb5bd0b8, 68f8be4710ef70435fee8d3c8bf4c1f7, and c1647c2958efc6aa1703a2b3e2d5c65f
- Description:
- To each causal diagram, and the structure that it represents, a dynamical system can be associated. From its qualitative analysis, the behaviours associated to the structure can be deduced. This paper introduces a piecewise linear dynamical system associated to a causal diagram. Some interesting results on the qualitative behaviour of the system can be obtained from this dynamical system. In this paper a method is proposed to implement automatically the construction of a piecewise linear dynamical system to each causal diagram, the study of its equilibria and its stability. This allows us to obtain, automatically, the behaviour modes associated to a causal diagram.
-
- Type:
- Document
- Date Created:
- 1992
- Collection:
- System Dynamic Society Records
- Collecting Area:
- University Archives
- Collection ID:
- ua435
- Parent Record(s):
- 23d738ba88f8333bc39725f9cb5bd0b8, 68f8be4710ef70435fee8d3c8bf4c1f7, and c1647c2958efc6aa1703a2b3e2d5c65f
- Description:
- After providing a framework for integration of System Dynamics and Expert Systems, this paper builds theoretical bases to integrate three main features of rule based reasoning mechanism into conventional System Dynamic models. Then we start to modify the System Dynamics modeling tools to adopt the integrated features. To illustrate, we demonstrate a prototype for integrated theories above.
-
- Type:
- Document
- Date Created:
- 1992
- Collection:
- System Dynamic Society Records
- Collecting Area:
- University Archives
- Collection ID:
- ua435
- Parent Record(s):
- 23d738ba88f8333bc39725f9cb5bd0b8, 68f8be4710ef70435fee8d3c8bf4c1f7, and c1647c2958efc6aa1703a2b3e2d5c65f
- Description:
- This paper is a research on the integration of system dynamics, protfolio and scenarios. The prototyping is used in developing the system dynamics model which is focused on the activities of business technology management. At here, we will discuss about the implementation and some simulation results of the BTMDSS model.
-
- Type:
- Document
- Date Created:
- 1992
- Collection:
- System Dynamic Society Records
- Collecting Area:
- University Archives
- Collection ID:
- ua435
- Parent Record(s):
- 23d738ba88f8333bc39725f9cb5bd0b8, 68f8be4710ef70435fee8d3c8bf4c1f7, and c1647c2958efc6aa1703a2b3e2d5c65f
- Description:
- The System Dynamics model which we are presenting here has been prepared with the purpose of examining the relations between the number of existing grant-holders in Spain and the number of researchers in active service in the sectors of Higher Education, Business and Public Research Organisms. The aim is to examine these variables in order to analyze the conditions of balance between the offer of potnential researchers trained while holding grants and the demand for new researchers trained while holding grants and demand for new researchers on the part of the science and technology system in Spain.
-
- Type:
- Document
- Date Created:
- 1992
- Collection:
- System Dynamic Society Records
- Collecting Area:
- University Archives
- Collection ID:
- ua435
- Parent Record(s):
- 23d738ba88f8333bc39725f9cb5bd0b8, 68f8be4710ef70435fee8d3c8bf4c1f7, and c1647c2958efc6aa1703a2b3e2d5c65f
- Description:
- It is often difficult to accommodate judgmental information together with quantitative data in an economic model. One approach is to embed human decision-makers as role players within a simulation exercise. Their behavior is recorded by the computer system, becoming a part of the modeling process. We consider some of the human interface requirements to accomplish this integration, a methodology using supervised linkage of spreadsheet with DYNAMO models, and an example of its application toward modeling the 1992 economic unification of Europe.
-
- Type:
- Document
- Date Created:
- 1992
- Collection:
- System Dynamic Society Records
- Collecting Area:
- University Archives
- Collection ID:
- ua435
- Parent Record(s):
- 23d738ba88f8333bc39725f9cb5bd0b8, 68f8be4710ef70435fee8d3c8bf4c1f7, and c1647c2958efc6aa1703a2b3e2d5c65f
- Description:
- For system dynamicists, it is important to understand how humanbeing solving problems and making decision in the real world. However, how humanbeing solving problems and making decision in the dynamic causal feedback environment are still not well understood both in psychology and in system dynamics. This paper is a preliminary study which attempts to deal with issues of problem solving, thinking strategy and pilot knowledge in a so called meta-dynamic decision making environment. The task was a computerized beer game modified from the board type beer game. Experiment results showed that there existed a goal-strategy dynamics in human problem solving. The thinking strategy contained both “structure-understanding” and “non-structure- understanding”. The pattern’s pilot knowledge from previous trials had influence on some subjects’ decision making. It’s possible influences in real world are discussed. Finally, from experiment results, two general problem solving processes ( the servomechanism process and cybernetic process) are proposed. Implications for system dynamics management flight simulator and systems thinking are also discussed.
-
- Type:
- Document
- Date Created:
- 1992
- Collection:
- System Dynamic Society Records
- Collecting Area:
- University Archives
- Collection ID:
- ua435
- Parent Record(s):
- 23d738ba88f8333bc39725f9cb5bd0b8, 68f8be4710ef70435fee8d3c8bf4c1f7, and c1647c2958efc6aa1703a2b3e2d5c65f
- Description:
- In order to understand the inner mechanism of corporations and incite their vigour, we create a model which provides us with the study of the development of new product R&D and advanced technology absorption, product life period, market promotion, the adjustment of the length of working time, productivity and hiring or firing of workforces.
-
- Type:
- Document
- Date Created:
- 1992
- Collection:
- System Dynamic Society Records
- Collecting Area:
- University Archives
- Collection ID:
- ua435
- Parent Record(s):
- 23d738ba88f8333bc39725f9cb5bd0b8, 68f8be4710ef70435fee8d3c8bf4c1f7, and c1647c2958efc6aa1703a2b3e2d5c65f
- Description:
- China’s economy had got its newest growth during the “No. 6 Five Year Plan” period, however, the problem of unbalanced production structure in China’s economy system turned to be more obvious and serious, reflected by the fact that the base economic production, defined as energy production, transportation and raw materials production faced a bigger lag in satisfying the social demand. Raw materials industry, including ferrous metal industry, nonferrous metal industry, chemical industry, building materials industry and forest industry showed even more serious tighteness in meeting the demand. The paper tackles with such a compliacated economy system by combining the qualitative method and quantitative methods. We believes that such a combined approach is effective in dealing with problems associated with a planned, but more and more market orientated economy, such as the economy system of China.