This paper constructs a system dynamics model on macroscopic management of a college which is based on an actual system operation of the college. The students, staff, fixed capital, finance, teaching and research as sectors are included in the model. Facing several important problems influencing development of the college various policy experiments are operated on the model. The experimental results show that the key factors influencing the system and what the possible approaches solving these problems are.
The rapid growth caused very serious environmental pollutions in Taiwan. This paper attempts to use the system dynamics methodology to construct a simple model to study the trade-offs between economic growth and environmental pollutions. The model is structured with feedback loops among three sectors; The government, the general public, and the industries. Environmental regulations with various implementation times and strengths are tested in the model to examine their effects on the smoothness of the economy and pollution changing pattern. The results show that a timely not-so-strict environmental regulation combined with an environmental education measure focused on lowering expectation on economic rate may be a better choice for Taiwan to go through the tough time more smoothly.
Inflation is one of the most troublesome problems China is recently faced with in the course of the economy reform. The inflation takes place in the form of general price rising. It becomes more serious and is greatly obstructing the healthy development of China’s economy. This situation results from many factors including the biased trend of the reform strategy, the deviations in implementation policies, the defects of the economic system, etc. The conventional theory about money amount has been used to analyze inflation before. This analytic method specially indicates the view point that inflation with no exception is a kind of money phenomenon by stressing the causal relationships between money amount and general price level, but it considers money supply as an exogenous variable controlled by the government’s policies and ignores the effect and restrictions from other economic factors. Therefore there are some limitations of this method in real uses. For this reason a new approach of system dynamic is put forward in the present paper. A dynamic model composed of a monetary market section, a commodity market section and a regulation section is developed. On the model a series of policy tests mainly concerning the two economy levers of price and interest rate are simulated with the consideration of china’s special situation. The cause and mechanism of suggestions are also made for elimination or controlling the inflation. The results of the paper may provide worthful references for China’s further economy reform.
In recent years, increased public awareness of the health and productivity costs associated with the use of cocaine and its potent derivative “crack” has served to heighten concern and renew debate over the most effective strategies for managing the drug problem. This paper presents a preliminary system dynamics model of the international cocaine trade. The initial model incorporates the various stages of the cocaine system from source country production to final consumption including: primary resource allocation and production; cocaine production; cocaine production and export; and U.S. demand, import, pricing, and consumption. The model is used to examine an ensemble of policies proposed by the National Strategy for Drug Control (White House 1989). Simulation results show the capacity of the system to exhibit a wide array of behavior modes depending on the type of intervention being applied and the aspect of the problem being targeted. Of particular interest from a policy standpoint is the implication of delays in physical and information flows for generating divergent short and long term policy results. Findings suggest a comprehensive approach combining demand and supply side policy leverage represents the most effective management strategy.
A System Dynamics model of an ecological system consisting of two patchily distributed populations is constructed to study the effects of inter-patch colonization on the persistence of the species. The model structure is primarily composed of the negative feedback loops dominant in local (within-patch) population regulation and a regional positive feedback loop coupled with two negative loops which regulate the inter-patch species colonization.The simulation results show that with colonization the population system always persists if at least one of the populations is larger that a minimum viable population size (MVP). If the species has sufficiently large colonizing ability, the populations are always able to reach the carrying capacity. Otherwise, the population with below MVP, there are two possibilities depending on the magnitude of species colonization ability: (1) both stabilize at the carrying capacity level and (2) both go extinct. The simulations also demonstrate that delays in colonization and population regulation may have distinctive impacts on species persistence and dynamics of the population system. The study may provide useful information for species conservation and design of nature reserves.
The last decade has been the accelerated development of what Yadav and Chand term “Organization Support Systems”- large scale, complex and extremely expensive computer based information systems (Yadav, 1989). The cost associated with such systems has increased the requirement for a sound methodology to evaluate the expected operational benefits and drawbacks resulting from their implementation, at as early a stage in the system life cycle as possible.An extensive survey of the literature in the field of information system evaluation, with a particular focus in the methodologies, tools and performance measures being used in practice, preceded the development of the methodology reported in this paper, and is presented in full elsewhere(Watts 1990).This paper comments on the findings from the review and reports on the development of a system dynamics based methodology for the assessment of proposed computer-based information systems (CIS), in terms of their potential to support organizational objectives.The methodology has been evaluated by application to two military CIS, at different stages in the system life cycle. These cases are reported separately(Watts and Wolstenholme, 1990; Henderson and Wolstenholme, 1990), but the indications are that the methodology can contribute throughout the system life cycle y providing a continuing reminder of the relevance of the CIS to the real-world system which is intended to support.
The appearance of Thomas Kuhn’s Structure of Scientific Revolutions engendered considerable discussion about the nature of scientific change. Kuhn challenges the prevailing view of science as a continuous, logical enterprise by attempting to debunk science’s myth of rationalism. As an historian as well as philosopher of science, he attempts to explain science’s extraordinary success not by developing methodological cannons divorced form scientific practice, but by looking at how scientists actually work.( Lakatos and Musgrave 1970, 236-237).Acknowledging the philosophical importance of actual scientific practice is controversial. Kuhn’s critics question both his characterization of science as mostly “puzzle –solving”, as well as his claim that such practice is necessary for scientific development. It will not be the task of this essay to rehearse these still unresolved debates. That is better left to the historians and philosophers. Rather, I would like to recognize another important contribution to the discussion, one that is orthogonal to any other that I know of. In “The Growth of Knowledge: Testing a Theory of Scientific Revolutions with a Formal Model,” John Sterman has built a model of Kuhn’s account of scientific change. He asks not whether Kuhn’s theory is dynamically consistent. He is interested in whether the behavior Kuhn describes (i.e. , paradigm emergence, normal science, crisis and revolution) actually follows logically from the assumptions Kuhn makes. To do so he constructs a system Dynamics computer model.
This paper examines the role that building and using a System Dynamics model plays in developing consensus within the management teams facing key strategic decisions. It considers the concept of the shared view that emerges within the team as their individual views of the company, its industry, and the socioeconomic climate are articulated and compared as part of the model development process. Examples are given based on two actual consulting assignments in which differing views held with the team concerning the competitive environment and the general outlook for the business initially pointed to quite different strategies. During these studies the emergence of the consensus and an agreed strategy was considered a major benefit alongside the forecasts and quantitative evaluations the model provided. By adding to the commitment of the team, by assisting in the communication with others and in improving human resource management and organization design, the approach also offers further benefits in the implementation phase of strategy management.In its analysis and use of examples drawn form consulting situations, this paper has emphasized the dual benefit of this approach in the hard sense of providing forecasts and an objective framework for quantitative evaluations, and the soft sense in terms of building consensus in the management team.
Since the mid 1970s, System Dynamics has contributed to the resolution of a wide range of business and legal disputes including contract claims and re-negotiations, management prudency hearings for nuclear power programs, and inquiries into the effects of government regulations on various industries. In these settings, a System Dynamics model can provide an objective, “transparent” view if a complex and emotional situation. The model can represent what happened and why, and what would have happened if certain events or conditions had not occurred. It can provide a basis for determining responsibility for delays, cost escalation, poor product performance, reliability and safety problems, complex situations are easier to understand and evaluate. The models and analyses become frameworks for debate and settlement.This paper describes the context, processes, and behaviors associated with many business-related legal disputes. The role of System Dynamics is dispute resolution is discussed in general terms, and then illustrated with a recent example. The example is a large contract claim for “delay and disruption.” That term refers to the indirect, secondary, or ripple effects of events or conditions (e.g., design changes) impacting an aerospace, shipbuilding, software development, or similar program. Delay and disruption impacts can be very substantial. They are the most difficult aspect of a change negotiation or claim to handle, and are the source of the most acrimony and disagreement in such disputes. The background of this case, the lawsuit, how the model was introduced into the legal proceedings, and how it helped to achieve a settlement, are described in detail. The paper concludes with a discussion of the practical results obtained from using System Dynamics in dispute resolution.
This article presenting a summary and analysis of the theory and method of System Dynamics on the author’s experience in planning of the coordinated development of science, technology, economy and social advancement in such cities as Beijing, llarbin, Anshan and Baotou, is aimed to find out the advantage disadvantage of the S.D approach to urban planning as well as to improve upon it.System Dynamics which is considered in this article to draw on system theory, information science and cybernetics, especially the feedback control principle and computer simulation, is a scientific theory and method that can find an effective application to improving and planning a multi-factor, non-linear, dynamic and/or strategy. In actual planning of coordinated development of the Chinese policy or strategy. In actual planning of coordinated development of the Chinese cities and regions, S.D is found superior in six (6) points while left five (5) respects to be desired, so the idea of establishing the S.D. dominated comprehensive model system is this developed to enhance and strengthen the above planning process.
This paper describes the application of a system dynamics based three-stage methodology (Wolstenholme, 1990) for the assessment of computerized information (CIS), to a proposed military logistics information system.The system in question was nearing the end of the Requirements Definition phase of the System Life Cycle process. A Benefit Assessment had been carried out by the consultants responsible for the design of the system. The Tools used by them had, however, encouraged the conclusion that any improvement in the information system must have a positive effect on organizational effectiveness directly proportional to that level of improvement, and that the overall level of improvement is the sum of individual gains. No study of the interaction of the physical operation and the information system had been carried out.
A system dynamics model of socio-economic development of Harbin in China has been Presented in the framework of the integrated economy-energy-environment system planning.The model simulates the activity mechanism of national economy of Harbin by taking the fixed capital of each industrial sectors as a major variable and controls the system behavior by taking the gap of energy supply and the gap of energy investment as feedback signals. Therefore the pre-established development targets of national economy can be reached by readjusting the investment allocation and production structure towards elimination of the energy and investment gaps.Through a series of policy stimulation, several socio-economic development planning scenarios of Harbin for year 2000 have been Compared with each other by examining some key issues, such as growth rate, investment ratio, investment allocation tenancy and production structure readjustment ad well as the improvement of scientific, technical and managemental level, etc. the resulted policy suggestions were proposed with much attention being paid by decision maker authority.This model can run on the personal computer under the support of the Professional DYNAMO Plus software, and try to connect SD model to other technical model, such as energy forecasting model, multi-object optimum energy supple model, etc. An idea which is about SD co-operated with other methods has been presented and that is the direction of the system dynamics method development.
Nonlinearity is the source of complexity. It gives rise to the change of the system behaviors, the evolution of structures and such phenomena as bifurcation, catastrophe, and even chaos. It is these phenomena, dovetailed with others, that weave out our multicolor and multifold world synergentically. With the development of science and technology, people become more and more interested in and capable of the study of nonlinearity so as to shed light on the nature of the world. In order to deal with nonlinearity more systematically, this paper elaborates a comprehensive description for the dynamical system. Then, we focus on the relationships between the characters of nonlinearity. We have successfully expounded some controversial concepts, cast new light on some important relations, and unified several concepts which are the central topics of many modern theories.
By means of system dynamics, main development modes and strategies on entire coordinated development of science, technology, economy and society of China have been studied. The paper studies the existed development mode and the long term possible obstacles, unfavorable factors and some constraints to the development in its different stages are analyzed quantitatively in the paper. Some long term and short term strategies and policies for continuous and entire coordinated development are presented, based on the system simulation and quasi-optimization.
This paper study how to develop education, technology and economy coordinativetly in central cities. It outlines the kind of issues which analyze and study the ways of describing science and technology level. The importance of the paper has two points: out is an new method being applied to calculate industry output, another is the study guiding line to the three sectors(science and technology, education and economy) in their entirety. The policy suggestions will have significant reference to make central cities’ long term development strategies.
This paper is focusing on study of influence of China’s recent economic adjustments and industrial structure changes on enterprises, particularly on these engaging in manufacturing. The paper analyzes major difficulties facing Shanghai, the largest industrial centre of China, and, using it as background, studies the decision-making strategy of a typical enterprise of Shanghai.
A simulation model of education and economy is used to analyze the education investment strategy in a region of China. The simulation results show the proportion of educational fees and investments must be suited to the economic developing level. Thus, it is necessary to continuously increase the proportions with economic growth. In order to be convenient for decision makers, a functional simulation support system is proposed.
In the paper, a system dynamics model of the Dutch health care system will be discussed. The description of the model will start with so called ‘patients flows’. It will be followed by a description of the most important factors that affect the patient’s flows and the costs generated by the system. Having outlined the system dynamics model, the outcomes of three policy alternatives aimed at reducing the costs of health care will be examined. They will serve to demonstrate that the system dynamic model does have the potential to be used in workshops to elicit and increase the knowledge policy makers have regarding the problem of rising costs of health care.
Many system dynamics modelers consider the process of model-building more important than the model itself. Model-building is supposed to generate considerable learning about a policy problem. Not only at the individual level but also at the organizational level. From the point of view of empirical evaluation research the question is how the occurrence of organizational learning as a consequence of a model-building process might be established. In this paper we will explore some of the key issues and difficulties involved in establishing organizational learning from model-building empirically.
A key issue in building computer models for decision support with client groups is the elicitation of knowledge from the mental models of participants. The system dynamics model-building process is quite complex and consists of several stages each demanding different types of knowledge to be elicited from the client group. In this paper we discuss a structured approach, employing various techniques, for the elicitation of knowledge in formulating and analyzing a system dynamics model of the Dutch Health Care System.