摘要:

AbstractThe use of aircraft carriers in offensive operations in waters where an enemy can deploy strong air forces is the subject of much debate, and it is sometimes asserted that the carriers could not survive long enough to discharge a mission. This article analyzes that proposition and shows that a wide range of possible outcomes exists, depending on the carrier commander's actions.By considering the fundamental mechanics of the problem, a number of options for technological improvement are suggested, and it is shown that they have widely differing, and sometimes very unexpected, effects on the outcome.The model requires a blend of discrete and continuous modeling, the main features of which are discussed in the Appendix.

ISSN:0883-7066    

DOI:10.1002/sdr.4260080302

出版商:John Wiley&Sons, Ltd.    

年代:1992

数据来源: WILEY

摘要:

AbstractThis articie examines a general infectious disease model and proposes a new epidemic threshold and an epidemic scale forecasting formula. Then a system dynamics model of an eruptive Spread of type‐A hepatitis in Shanghai in 1988 is presented. Various problems are resolved: simulating the incubation period of type‐A hepatitis; fitting the simulation results to real data; analyzing the reason that the predicted second peak of the eruptive spread did not occur. Short‐and long‐term prospects for recurrence are considered, especially the mechanisms of periodic epidemics and eruptive spreads of type‐A hepatitis. The results of this study have import for the prevention and control of type‐A hepatitis and other infectio

ISSN:0883-7066    

DOI:10.1002/sdr.4260080303

出版商:John Wiley&Sons, Ltd.    

年代:1992

数据来源: WILEY

摘要:

AbstractWhile most examples of complex motion in economic dynamics employ a discrete‐time concept, chaos can also emerge in continuous‐time, nonlinear economic models. It is argued that, (depending on the level of aggregation in the economy) the use of the continuous‐time concept can be mandatory in economic dynamics. The Šil'nikov scenario, based on the existence of homoclinic orbits, is used as a formal means to illustrate the emergence of complex motion in two simple examples from traditional business cycle theory. The consideration of slight nonlinearities in a generalized version of the standard Metzler model with inventories and in Phillips' multiplier‐accelerator model can imply chaotic

ISSN:0883-7066    

DOI:10.1002/sdr.4260080304

出版商:John Wiley&Sons, Ltd.    

年代:1992

数据来源: WILEY

摘要:

AbstractNotes and Insights is a forum for discussion and debate about current issues in the philosophy and application of the system dynamics approach, and a marketplace for the exchange of information about current research, policy issues, and teaching experiences. Manuscripts treating material particularly suited to presentation in short form (less than 2,000 words) should be sent to Erich Zahn, Betriebswirtschaft‐liches Institut, Abt. IV, Universitat Stuttgart, Keplerstr. 17, D‐7000 Stuttgart 1, Germany.Since formal modeling requires having a model boundary encompassing finite complexity so that deductive logic is possible, complex problems must be partitioned into simpler parts before being analyzed. 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 explores ways in which a complex problem may be appropriately sliced so that the models of partitions can serve as effective tools for policy des

ISSN:0883-7066    

DOI:10.1002/sdr.4260080305

出版商:John Wiley&Sons, Ltd.    

年代:1992

数据来源: WILEY

摘要:

AbstractIn this section the SystemDynamics Reviewpresents problems having the potential to stimulate system dynamics research. Articles may address real‐world dynamic problems that could be approached fruitfully from the system dynamics perspective, or methodological problems affecting the field. A paper submitted to the Research Problems section should concisely motivate and define a problem and start a process of conceptualization or formulation that can open the way for further studies. Manuscripts not exceeding 2,000 words should be sent to George P. Richardson, Milne 308, Rockefeller College, S.U.N.Y., Albany, NY 12222, U.S.

ISSN:0883-7066    

DOI:10.1002/sdr.4260080306

出版商:John Wiley&Sons, Ltd.    

年代:1992

数据来源: WILEY

摘要:

AbstractThis section of the System DynamicsReviewis an eclectic source of information on items of interest to the system dynamics community. Conferences, articles, books, dissertations, speeches, software and hardware products, and teaching materials will be mentioned in this space. The purpose of the section is to provide summaries to help the system dynamics community keep abreast of recent progress related to the field and to anticipate important future events. Submissions covering a wide range of areas and information of possible interest to system dynamicists are encouraged and should be sent to R. Joel Rahn, Faculte des Sciences de l'Administration, Université Laval. Ste. Foy, Quebec, GIK 7P4, Canada. Fax: (418) 656‐2624. E‐mail: rahnj‐@lavalvml.bitmet. rahnj@vm1. ula

ISSN:0883-7066    

DOI:10.1002/sdr.4260080307

出版商:John Wiley&Sons, Ltd.    

年代:1992

数据来源: WILEY

ISSN:0883-7066    

DOI:10.1002/sdr.4260080308

出版商:John Wiley&Sons, Ltd.    

年代:1992

数据来源: WILEY

ISSN:0883-7066    

DOI:10.1002/sdr.4260080309

出版商:John Wiley&Sons, Ltd.    

年代:1992

数据来源: WILEY

ISSN:0883-7066    

DOI:10.1002/sdr.4260080310

出版商:John Wiley&Sons, Ltd.    

年代:1992

数据来源: WILEY

ISSN:0883-7066    

DOI:10.1002/sdr.4260080301

出版商:John Wiley&Sons, Ltd.    

年代:1992

数据来源: WILEY