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- Type:
- Document
- Date Created:
- 2005 July 17-2005 July 21
- Collection:
- System Dynamic Society Records
- Collecting Area:
- University Archives
- Collection ID:
- ua435
- Parent Record(s):
- 23d738ba88f8333bc39725f9cb5bd0b8, 3c582e6f5cf305ef0030c7471b499022, and cc5bb0ac12a5b68b26b1583548898dae
- Description:
- In this paper, we present a novel project management model that incorporates several features yet to be actively addressed in the literature and focuses on earned value management. The model utilizes the basic structures employed in building project dynamics models. The effects of time-varying project team size, of training and communication overload, and of change management are incorporated into our model. With the help of our model and a hypothetical software technology project, we demonstrate how our system dynamics model can contribute beyond basic project tools like MS Project, in generating the earned value management indicators required by project managers under different scenarios and starting assumptions. Results are consistent with well-known behavior of projects in that the later the changes arrive, the longer is the delay in completing the projects. These phenomena are propagated through the earned value measures to see the actual effects upon schedule and cost performance indices. The study also focuses on the use of earned value measures as well as critical chain concepts to understand how these separately impact project duration and cost.
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- Type:
- Document
- Date Created:
- 2005 July 17-2005 July 21
- Collection:
- System Dynamic Society Records
- Collecting Area:
- University Archives
- Collection ID:
- ua435
- Parent Record(s):
- 23d738ba88f8333bc39725f9cb5bd0b8, 3c582e6f5cf305ef0030c7471b499022, and cc5bb0ac12a5b68b26b1583548898dae
- Description:
- The Department of Homeland Security (DHS) is funding the development of a Critical Infrastructure Protection Decision Support System (CIP DSS) that is intended to be used by DHS decision makers to assess the impacts of deliberate attacks or disruptions on the United States infrastructures and how they might be mitigated by investments in protective or recovery technologies. One of the 17 critical infrastructures is the Defense Industrial Base. The basic mechanisms of such a model are the flows, especially surge response flows, of war materiel from private sector defense industries to the Department of Defense (DoD). In order to capture surge flows, additional models of military logistics, especially deployment, and military missions are needed to drive the behavior of interest. Basic system dynamics models are being considered to provide this feedback to the basic mechanisms. With this consideration of military mission effectiveness, the models main output decision metric is an estimation of casualties, which presents its own system dynamics modeling challenges.
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- Type:
- Document
- Date Created:
- 2005 July 17-2005 July 21
- Collection:
- System Dynamic Society Records
- Collecting Area:
- University Archives
- Collection ID:
- ua435
- Parent Record(s):
- 23d738ba88f8333bc39725f9cb5bd0b8, 3c582e6f5cf305ef0030c7471b499022, and cc5bb0ac12a5b68b26b1583548898dae
- Description:
- Capturing Project Dynamics with a New Project Management Tool: Project Management Simulation Model (PMSM) Ali Afsin Bulbul Portland State University Systems Science Ph.D. Program Harder House 1604 SW 10th Ave. Portland, OR 97201 Phone: (503) 221-4576 Fax: (503) 725-8489 afsin@pdx.edu In this research, traditional project management concepts, methods, and their deficiencies relative to increasing complexity of projects is discussed. System Dynamics (SD) modeling is proposed as a complementary project management tool to be used at the higher level to augment operational level project management methods. The potential usage of SD models to promote the learning from projects, both in individual and organizational dimensions, is discussed. Working as a project management laboratory, SD project models can be successfully used to improve understanding of the project process. They can be used to design the project in the project-planning phase, to monitor and control the project in the project-execution phase, and to learn from the project in the post-mortem phase working as a learning infrastructure. A generic SD project management simulation model (PMSM) is built to serve for this purpose. The model structure and the graphical user interface are explained briefly. Tests performed to validate the model revealed that the model is appropriately designed, works properly, and it is robust relative to the purpose of the model.
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- Type:
- Document
- Date Created:
- 2005 July 17-2005 July 21
- Collection:
- System Dynamic Society Records
- Collecting Area:
- University Archives
- Collection ID:
- ua435
- Parent Record(s):
- 23d738ba88f8333bc39725f9cb5bd0b8, 3c582e6f5cf305ef0030c7471b499022, and cc5bb0ac12a5b68b26b1583548898dae
- Description:
- The objective of the paper is to show that the one of the main source of macroeconomic investment instability is similar to that which makes difficult managing supply line in famous Beer Game developed by the system dynamics group of MIT Sloan School of Management. It will be pointed out that ignoring production time delays causes instability not because economic agents simply ignore supply line delays, but because they adjust their expectations more rapidly than the delays involved in supply lines, whatever those delays could be. The paper is structured in three sections. In the first we present the classic Phillips argument about unintentional destabilizing effects of stabilization policy in modern dynamic system language, in order to show how to build a simplified macroeconomic supply line model for investment dynamics; in the second section, the macroeconomic model is developed and simulated. Third section concludes the paper suggesting that the inclusion of production time delays in macroeconomic models reopens the space to the control theory in stabilization policy debate
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- Type:
- Document
- Date Created:
- 2005 July 17-2005 July 21
- Collection:
- System Dynamic Society Records
- Collecting Area:
- University Archives
- Collection ID:
- ua435
- Parent Record(s):
- 23d738ba88f8333bc39725f9cb5bd0b8, 3c582e6f5cf305ef0030c7471b499022, and cc5bb0ac12a5b68b26b1583548898dae
- Description:
- This paper introduces the notion of increasing returns to economic activity agglomeration and develops a formal system-dynamic model where this notion is used to explain the self-organizing nature of the spatial structure of industrial clusters. In this model, both pecuniary and external economies based on knowledge spillovers are considered.
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- Type:
- Document
- Date Created:
- 2005 July 17-2005 July 21
- Collection:
- System Dynamic Society Records
- Collecting Area:
- University Archives
- Collection ID:
- ua435
- Parent Record(s):
- 23d738ba88f8333bc39725f9cb5bd0b8, 3c582e6f5cf305ef0030c7471b499022, and cc5bb0ac12a5b68b26b1583548898dae
- Description:
- Laboratory studies have shown that people cannot handle the time con-stants in dynamic tasks. Yet they obviously cope with such tasks with some success outside the laboratory. This study is one in a series of studies that examine the hypothesis that people cope by relying on heuristics that allow them to simplify the task. The heuristic studied here was that of relying on frequency differences, i.e., what Reason (1990) calls frequency gambling. It examines the effects of varying the relative frequency of scenarios that require different responding, and where relying on frequency rather than learning the actual time con-stants will lead to some success. The results show that the participants did not learn the time constants, that frequency had a strong effect on their decisions, but that their responding also seemed to be influenced by another heuristic identified in earlier studies, viz., that of rapid and massive responding. Implications of these findings for system dynamics modellers are discussed.
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- Type:
- Document
- Date Created:
- 2005 July 17-2005 July 21
- Collection:
- System Dynamic Society Records
- Collecting Area:
- University Archives
- Collection ID:
- ua435
- Parent Record(s):
- 23d738ba88f8333bc39725f9cb5bd0b8, 3c582e6f5cf305ef0030c7471b499022, and cc5bb0ac12a5b68b26b1583548898dae
- Description:
- Organizations may fail to adopt sustainable solutions as a result of incomplete and/or inaccurate feedback into the decision making process. Events that cause harm - environmental, health, or social - are commonly the delayed effect of a prior course of action, itself the result of decisions that emerge from endogenous policy. By accelerating the cost of future harm into current period decisions, producers and purchasers have greater access to the quantity and quality of information that influence decisions to produce and consume. The creation of a financial policy structure that makes future, long-term costs of production, promotion, and consumption explicit in the decision process will correct a current deficiency in the analysis of costs and benefits made by producers and purchasers. Such a feedback loop would correct a structural market failure and could reduce the need for governmental regulation.
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- Type:
- Document
- Date Created:
- 2005 July 17-2005 July 21
- Collection:
- System Dynamic Society Records
- Collecting Area:
- University Archives
- Collection ID:
- ua435
- Parent Record(s):
- 23d738ba88f8333bc39725f9cb5bd0b8, 3c582e6f5cf305ef0030c7471b499022, and cc5bb0ac12a5b68b26b1583548898dae
- Description:
- Environmental strategies such as Zero-to-Landfill are gaining increasing attention throughout the world. Product take back is a significant means of ensuring that products that have reached the end of their useful lives are reclaimed for reuse, remanufacturing, or recycling. Such a strategy is expected to minimize environmental impacts, reduce overall resource consumption, and provide economic value to manufacturers and consumers. The reverse logistics, however, can be quite complicated as product collection, product disassembly, processing, component returns, and component reclamation must be considered. Further, the costs and magnitude of the requisite system must be projected to support appropriate planning and execution. In this paper, we present a model of a reverse logistics system for a consumer product. The impacts of closed-loop logistics on product adoption rate, product costs, and component reliabilities are balanced against the cost of new infrastructure, shipping and tracking, and processing and inventorying of expended components. We illustrate how a reverse logistics approach may develop as a function of product adoption, the total value of returned components, product reliability, and product lifetime. A Zero-to-Landfill strategy has a significant potential to improve the triple bottom line people, planet, and profit of companies that adopt it.
-
- Type:
- Document
- Date Created:
- 2005 July 17-2005 July 21
- Collection:
- System Dynamic Society Records
- Collecting Area:
- University Archives
- Collection ID:
- ua435
- Parent Record(s):
- 23d738ba88f8333bc39725f9cb5bd0b8, 3c582e6f5cf305ef0030c7471b499022, and cc5bb0ac12a5b68b26b1583548898dae
- Description:
- This paper presents a dynamic hypothesis explaining the system dynamics underlying the identity theft epidemic. The causal loop structure synthesizes current understanding of the problem and suggests that any strategy to address the identity theft epidemic by primarily focusing on prosecuting thieves without effectively mitigating the underlying forces is doomed to failure. The causal loop diagram elucidates the dominant feedback structure ...a collection of rapid-feedback, self-reinforcing dynamics that generate ample opportunities for would-be thieves. Preliminary results from the analysis provide a foundation for exploring policy options through a full working model, yet to be developed.
-
- Type:
- Document
- Date Created:
- 2005 July 17-2005 July 21
- Collection:
- System Dynamic Society Records
- Collecting Area:
- University Archives
- Collection ID:
- ua435
- Parent Record(s):
- 23d738ba88f8333bc39725f9cb5bd0b8, 3c582e6f5cf305ef0030c7471b499022, and cc5bb0ac12a5b68b26b1583548898dae
- Description:
- PANEL: Andrei Borshchev, Xjtek,Russia; Nate Osgood MIT,USA; Mark Paich, Decisio Consulting, USA; Hazhir Rahmandad, Sloan School of Management, MIT, USA; Mark Heffernan, International System Dynamics, Australia; Sara Metcalf, University of Illinois, USA; Chris Johnson General Electric, USA;Geoff McDonnell UNSW Australia; Other users from industry. There is increasing interest in combining agent based (AB) and system dynamics (SD) modeling methods. This workshop will demonstrate the differences between the AB and SD approaches using some popular examples from the Dynamics of Contagion and the Diffusion of Innovation, using the AnyLogic multi-method software. It will also walk through some practical examples of the use of combined methods in health, marketing and other industries. The workshop will conclude with a "warts and all" panel discussion involving experienced SD practitioners and researchers in SD, geography and computer science, all of whom are adding AB methods to their work.