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- Type:
- Document
- Date Created:
- 1985
- Collection:
- System Dynamic Society Records
- Collecting Area:
- University Archives
- Collection ID:
- ua435
- Parent Record(s):
- 23d738ba88f8333bc39725f9cb5bd0b8, 8cc5e98280358f60c3a33cc99e75a20e, and 11576afb39e5cd4a779a3912c119ca81
- Description:
- Despite the power of our framework as a tool for learning, system dynamics has yet to penetrate into the economics discipline. A different approach to dissemination of system dynamics into the microeconomics mainstream is presented. In contrast with the traditional product-focused strategy, the new approach uses microeconomic theory as a context for the development of student modeling skills. The approach relies heavily on the STELLA software. It is embodied in a book for introductory and intermediate microeconomics students. The general specifications and design of the approach are presented. To illustrate the approach, a sample laboratory session from the book is provided.
-
- Type:
- Document
- Date Created:
- 1985
- Collection:
- System Dynamic Society Records
- Collecting Area:
- University Archives
- Collection ID:
- ua435
- Parent Record(s):
- 23d738ba88f8333bc39725f9cb5bd0b8, 8cc5e98280358f60c3a33cc99e75a20e, and 11576afb39e5cd4a779a3912c119ca81
- Description:
- This paper uses a dynamic model to study the effect of distant and home water fishing on the Atlantic salmon fisheries. Under open access, capacity in each fishery oscillates due to overfishing and adjustment lags in capital investment. It is shown that development of a feeding ground fishery imposes significant costs on home water fisheries. In a regulated environment, joint operation of the two fisheries can result in higher total catches and profits than when a moratorium is placed on feeding ground fishing.
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- Type:
- Document
- Date Created:
- 1985
- Collection:
- System Dynamic Society Records
- Collecting Area:
- University Archives
- Collection ID:
- ua435
- Parent Record(s):
- 23d738ba88f8333bc39725f9cb5bd0b8, 8cc5e98280358f60c3a33cc99e75a20e, and 11576afb39e5cd4a779a3912c119ca81
- Description:
- During the last five years a system dynamics model of the dental health care system of the Netherlands has been developed.The model consists of six submodels, capturing the major demographica1, pathological, psychological, sociological and economical processes of supply and demand of dental care. Two income-categories differentiating between two classes of insurance ("Sickfund” and “Non-Sickfund”), and six age-categories are distinguished. The model comprises ten types of dental treatments. Alternative policies with respect to restoring the lost equilibrium between supply and demand of dental care are tried out, and compared with the base-run. Dependent on the considered time-horizon, and the interests of different parties (dentists, dental students, dental hygienists), different policy-scenario's turn out to be more attractive in redressing the balance.
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- Type:
- Document
- Date Created:
- 1985
- Collection:
- System Dynamic Society Records
- Collecting Area:
- University Archives
- Collection ID:
- ua435
- Parent Record(s):
- 23d738ba88f8333bc39725f9cb5bd0b8, 8cc5e98280358f60c3a33cc99e75a20e, and 11576afb39e5cd4a779a3912c119ca81
- Description:
- This paper describes the design and application of a System Dynamics Model in simulating the future of an Engineering Company. The stress has been given in this paper to explain the application of System Dynamics principles in designing long range policies of the company. The Model is being used by the company in testing various strategies to be adopted by the management related to new projects for expansions and modernisation by simulating the impact of these strategic decisions on the objective variable. The Model assists the management in designing their long range policies to achieve the corporate objectives.
-
- Type:
- Document
- Date Created:
- 1985
- Collection:
- System Dynamic Society Records
- Collecting Area:
- University Archives
- Collection ID:
- ua435
- Parent Record(s):
- 23d738ba88f8333bc39725f9cb5bd0b8, 8cc5e98280358f60c3a33cc99e75a20e, and 11576afb39e5cd4a779a3912c119ca81
- Description:
- A Simulation Model for Corporateing Planning has been designed for a Steel Plant based on System Dynamics principles. This Model has been designed for Material flow that takes place through a group of 12 production shops arranged in six stages of production. The Model requires a time variant input of Demand of 17 categories of finished steel products and 3 categories of Raw materials. The Model generates behaviour of various objectives based on the assumptions of the environment. The Model can be used for simulating the impact of various strategic policy decisions on the corporate objectives. The Model also guides the management in designing their long term investment policies related to expansion, modernisation and debottlenecking.
-
- Type:
- Document
- Date Created:
- 1985
- Collection:
- System Dynamic Society Records
- Collecting Area:
- University Archives
- Collection ID:
- ua435
- Parent Record(s):
- 23d738ba88f8333bc39725f9cb5bd0b8, 8cc5e98280358f60c3a33cc99e75a20e, and 11576afb39e5cd4a779a3912c119ca81
- Description:
- By analysing the dynamics of a simple problem of urban migration, this paper illustrates how chaotic behaviour can be internally generated even in a relatively small (4-level) System Dynamics model. Two different groups of minority families are considered to move around between three sectors of a city. This migration occurs in response to changes in certain social indicators which we take to be related to the number of families already living in the respective sectors. Type I families, for instance, prefer to live in areas with many households of the same kind and tend to avoid neighbourhoods with many type II families. Type II families, on the other hand, although also they like to live together, are at the same time attracted to areas with many type I families. For normal parameter values, this system has an unstable equilibrium point. In base case it exhibits a limit cycle behaviour with the non-linear limiting factors associated with a slowing down in the rate of emigration from a certain sector as the number of remaining families approach zero. We show how the system develops through a Feigenbaum cascade of period doubling bifurcations as the inclination of type II families to move into areas with many type I families is reduced by. 15%. By calculating the largest Lyapunov exponent for the system we finally show how the chaotic behaviour is quantitatively distinguishable even from the most complicated limit cycle behaviour.
-
- Type:
- Document
- Date Created:
- 1985
- Collection:
- System Dynamic Society Records
- Collecting Area:
- University Archives
- Collection ID:
- ua435
- Parent Record(s):
- 23d738ba88f8333bc39725f9cb5bd0b8, 8cc5e98280358f60c3a33cc99e75a20e, and 11576afb39e5cd4a779a3912c119ca81
- Description:
- Forecasting for complex nonlinear systems has proven to be elusive. Investigators have assumed the causes to be too little data and overly-simplified models. Recent studies in climatology reveal that nonlinear systems behave in ways quite different from the linear or static systems of traditional science and engineering. The behavior of nonlinear systems can be cyclical or essentially stochastic and usually is a mixture of both. New techniques, such as "attractors," are being devised to facilitate analysis. Methodologies must be applied with due consideration to the structure of the system under investigation.
-
- Type:
- Document
- Date Created:
- 1985
- Collection:
- System Dynamic Society Records
- Collecting Area:
- University Archives
- Collection ID:
- ua435
- Parent Record(s):
- 23d738ba88f8333bc39725f9cb5bd0b8, 8cc5e98280358f60c3a33cc99e75a20e, and 11576afb39e5cd4a779a3912c119ca81
- Description:
- A conceptual framework for modelling the dynamics of environmental systems is presented. It is argued that apparently stable systems can evolve via bifurcation when critical thresholds are exceeded. When a system is forced further away from equilibrium dissipative structures emerge. These dissipative structures are characterized by stochastic, non-linear feedback mechanisms which have the capacity to transform an apparently stable environmental system into a relatively more complex one which evolves. Some examples of these structures are simulated using system dynamics and the implications for further research are discussed.
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Mandal, Purnendu with Eric F. Wolstenholme, "National Development Policies for Developing Countries"
- Type:
- Document
- Date Created:
- 1985
- Collection:
- System Dynamic Society Records
- Collecting Area:
- University Archives
- Collection ID:
- ua435
- Parent Record(s):
- 23d738ba88f8333bc39725f9cb5bd0b8, 8cc5e98280358f60c3a33cc99e75a20e, and 11576afb39e5cd4a779a3912c119ca81
- Description:
- The work described in this paper is an extension of earlier work by the same authors on analysis of national development planning. A brief description is presented here of the system dynamics model developed for this earlier work as a basis for explaining its recent application to development policy design. A taxonomy of development policies is presented and the results of analysing seven policies, within an adaptive model framework, are presented, which are aimed at improving and achieving both growth and equity. Each policy is examined under conditions of continuous proportional control and discrete control based on a sector criticality.
-
- Type:
- Document
- Date Created:
- 1985
- Collection:
- System Dynamic Society Records
- Collecting Area:
- University Archives
- Collection ID:
- ua435
- Parent Record(s):
- 23d738ba88f8333bc39725f9cb5bd0b8, 8cc5e98280358f60c3a33cc99e75a20e, and 11576afb39e5cd4a779a3912c119ca81
- Description:
- Mid-volume, mid-variety operations characterize flexible manufacturing systems (FMS) or job-shops found in most factories. Profitability of FMS depends upon effective scheduling of material flow, machine use, staffing, and buffer capacities. Many systems adjust to changes in demand and equipment failure in the long term. In the short term, however, large changes may occur in inventories, staffing requirements, and machine utilization. In general, these large changes reduce production efficiency and profits. An approach is demonstrated for attenuating or eliminating changes or swings in a system when there occurs some abrupt change. Delays and delay parameters in the system model are adjusted, subject to practical constraints, to produce a smooth and rapid transition after the change. A simple econometric model is used for illustration. A symbolic and algebraic manipulation language is required to implement the approach.