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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:
- One of our major challenges in system dynamics, and a prerequisite for successful policy design, is to establish an understanding of the relationship between the structure and the behavior of complex, dynamic systems. In this paper, we propose the utilization of a combination of a phase- and a time-plot, called a structure-behavior diagram, to obtain such an understanding. To demonstrate its usefulness, we apply the diagram in order to explain the transient behavior of a simple ecological system and illustrate the dynamics of its modes of behavior under changing harvesting intensity. Our discussion focuses on equilibria and shifts in the dominant polarity and indicates a qualitative difference between the two with respect to resistance to bifurcations.
-
- 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 Delphi method has been used as a method of knowledge capture and consensus building in a variety of social and managerial areas for a considerable period of time and more recently it has been applied in the field of System Dynamics. This paper describes research into the development and application of a computerised version of the Delphi method to assist the development of System Dynamics models. It has been developed in the context of project aimed at improving the design and assessment of computer based information systems.The features of a Hypermedia based Delphi system that has been developed for the Apple Macintosh are described and the results of its application to a modelling exercise are discussed, with particular emphasis on its ability to create consensus influence diagrams.
-
- 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 discusses how to use the simulation data obtained from the adiabatic reaction calorimeter (ARC) to design the emergency relief system for chemical reactors and storage vessels to overcome the problem of reactors explosions resulted from excessive pressure and thus the disastrous incidents can be avoided. Here the styrene polymerization reaction is choosen as the reaction system to describe the design of emergency relief system using the ARC data. The simulation results show that the change of the initiator and the monomer concentration will influence the maximum temperature, pressure and the rate of temperature rise in the reactor. The simulation results also illustrate that in the designing of the emergency relief system, the larger the overpressure is, and the smaller the vent diameter will be needed.
-
- 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 treat some problems of controlling the development of a two-phase system which is identified with the evolution of its inter-face. First we study the class of so-called decision change regimes and find out an estimate for the number of decision changes. Then we consider the possibility of optimal control in this class.
-
- 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:
- :There are many different systems approaches and styles of systems thinking that have developed over the past three decades. There a few conceptual frameworks on which to compare the relative merits of each approach. This paper will propose such a conceptual framework, the “systems paradigms framework”. Within the context of this framework new systems approach will be described. It is labelled the “integrative systems approach”. It will be argued that the system dynamics perspective is the best existing example of the integrative approach. The integrative approach will be compared to the hard systems, soft systems, and cybernetic systems approaches, in terms of the systems paradigms framework.
-
- 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 this paper a professional training schedule on system dynamics for engineers is discussed on the basis of ten years teaching and training practice.Three main parts are considered in detail. These are theory, practice, and final performance test. All examples included are to meet the specific necessity of engineers, and are coming from practical problems.An overall block Diagram of Training is presented. Practice shows this schedule is efficient and attractive.
-
- 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:
- Using a generic model framework, a consortium comprised of three manufacturing firms and one service company was able to create realistic representations of their internal and external competitive environments and analyze the consequences of their competitive strategies. The interface designed with the framework has proven to be a useful tool to support decision makers when they present their findings and analyses to their colleagues. Strategy simulations and the resulting scenarios can be useful tools for understanding the interrelationships of different elements within a competitive system and for identifying critical leverage points that may help a firm create a competitive advantage over its competitors.
-
- 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:
- Various uses of system dynamics models in understanding and managing software projects have been discussed in a series of articles by Tarek Abdel-Hamid and Stuart Madnick. Our work extends Abdel-Hamid and Madnick’s work by constructing a simulation game that can be used by mangers as a participatory learning laboratory. The game is implemented on IBM-PC environment, using the graphics-based spreadsheet software WingZ. Initial tests of the simulation game have demonstrated it to be robust and realistic. The game is now in the process of being tested extensively by players with different backgrounds: undergraduates and graduate students of system analysis, faculty members, and software/MIS professionals. In addition to describing the game, our talk will contain lessons learned from these extended tests and experiments. The presentation will also involve an active demonstration.
-
- 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:
- Long delivery delays and long asset life times can create market conditions that are not conductive to learning. An experiment recreated market cycle of 8 to 23 years. Subjects operated in a sequence of two 40 period market trials. The hypothesis that learning is helped by higher market frequency was corroborated, yet it was found that subjects transfer poorly when market frequencies remain unchanged across trials. This is explained by the fact that subjects in the changed frequency condition also expect a changed environment and so adjust behavior. When subjects do not expect change in market behavior, as in the unchanged frequency condition, subjects induce negative transfer, i e they transfer decision timing from the past. Since the markets’ external environments never remain identical, such transfer is less appropriate than structural transfer. Implications for stabilizing unstable markets and training professionals are finally laid out.
-
- 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 introduces a simple dynamical system associated to the influence diagram, which contains only qualitative information. It is analysed how with the information in the influence diagram only limited conclusions about the behavior of the system can be reached. However, with some extra qualitative information regarding the relative weight of the influences those limitations are overcome.