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- Type:
- Document
- Date Created:
- 2008 July 20-2008 July 24
- Collection:
- System Dynamic Society Records
- Collecting Area:
- University Archives
- Collection ID:
- ua435
- Parent Record(s):
- 23d738ba88f8333bc39725f9cb5bd0b8, ce498623f0349395d0a141a0525190a0, and 6cbae5a21467df4434abbc87da443217
- Description:
- Although large developed System dynamics model can be applied on different ecological system in this paper it is applied on Kastela region in Croatia. The Computer Simulation Sub model of The Ecological Regional Subsystem of the "KASTELA BAY" is an extra relevant submodel of The System Dynamics Computer Simulation Model of the KASTELA BAY which has been developed with the help of System Dynamics. It is, in its essence, a continuous model because it is presented as a system of non-linear differential equations. At the same time, it is a discrete model, because it is presented as a system of linear differential equations (System Dynamics DYNAMO - software package). Its DT (length of intervening time = computation interval) is chopped in full accordance with the Sampling Theorem (Shannon and Koteljnikov). The System Dynamics Computer Simulation Model of the "Kastela Bay" also employs certain experience gathered by experts who had worked on the preparation of projects: "Blue Plan" and "The Methodological Basis for the Scenario of the Management of Natural Resources of the "Kastela Bay"" (1991).
-
- Type:
- Document
- Date Created:
- 2008 July 20-2008 July 24
- Collection:
- System Dynamic Society Records
- Collecting Area:
- University Archives
- Collection ID:
- ua435
- Parent Record(s):
- 23d738ba88f8333bc39725f9cb5bd0b8, ce498623f0349395d0a141a0525190a0, and 6cbae5a21467df4434abbc87da443217
- Description:
- This paper reports on a preliminary version of a System Dynamics model of the
-
- Type:
- Document
- Date Created:
- 2008 July 20-2008 July 24
- Collection:
- System Dynamic Society Records
- Collecting Area:
- University Archives
- Collection ID:
- ua435
- Parent Record(s):
- 23d738ba88f8333bc39725f9cb5bd0b8, ce498623f0349395d0a141a0525190a0, and 6cbae5a21467df4434abbc87da443217
- Description:
- We propose an Integrated Systemic Theory of Catastrophes (ISTC) using System Dynamics to model and to understand common systemic structures and behaviours of catastrophes. Current catastrophe research concentrates on a specific field and does not capture complex multi-field catastrophe scenarios that cannot be reduced to a single scientific field. For example, when looking at famines the elements of the relevant feedback loops belong to different fields of science (climate, precipitation, soil conditions, population density etc.) and no single of these sciences alone can identify the systemic structure generating famines. In this paper we introduce the concept of catastrophe archetypes that function as a central element of the ISTC. Catastrophe archetypes describe systemic structures responsible for catastrophes to occur and make underlying catastrophe dynamics visible that are normally not directly seen. Within the ISTC the catastrophe archetypes will be used as diagnostic-, planning- and theory building tools to explore catastrophes systemically.
-
- Type:
- Document
- Date Created:
- 2008 July 20-2008 July 24
- Collection:
- System Dynamic Society Records
- Collecting Area:
- University Archives
- Collection ID:
- ua435
- Parent Record(s):
- 23d738ba88f8333bc39725f9cb5bd0b8, ce498623f0349395d0a141a0525190a0, and 6cbae5a21467df4434abbc87da443217
- Description:
- The absorption kinetics of subcutaneously injected soluble insulin is unusual in that clinical experiments show that a slow initial absorption after a couple of hours is replaced by a significantly faster absorption. Moreover, experiments with different injection volumes and insulin concentrations demonstrate that there is both a volume and a concentration effect. The slow initial phase disappears if either the injected volume or the concentration of the injected insulin is reduced. On the other hand, in the limits of very low concentrations or small volumes, a tail develops on the absorption curve, representing a new type of slow process. A System Dynamics model of this absorption scenario was original developed in collaboration with the Steno Memorial Hospital. In spite of the fact that the insulin concentrations have increased by an order of magnitude, the model continues to correctly predict the absorption curves, and we are presently using variants of the model to explain the absorption curves for other insulin forms, some of which are bound to protein as they are injected or bind to protein as they enter the blood vessels while yet others are injected in crystalline form or precipitate immediately after the injection.
-
- Type:
- Document
- Date Created:
- 2008 July 20-2008 July 24
- Collection:
- System Dynamic Society Records
- Collecting Area:
- University Archives
- Collection ID:
- ua435
- Parent Record(s):
- 23d738ba88f8333bc39725f9cb5bd0b8, ce498623f0349395d0a141a0525190a0, and 6cbae5a21467df4434abbc87da443217
- Description:
- Military strategists are increasingly recognizing that planned interventions sometimes fail to achieve their goals, especially in the long term, because planning is done with a limited view of possible outcomes rather than a whole-systems perspective. The systems modeling methodology of system dynamics is well-suited to address many of the dynamically complex problems that arise in the context of military planning issues. The purpose of this paper is to highlight key features of the system dynamics method as it might be applied to military planning. The paper develops an illustrative model of a stylized military planning situation and uses it to illustrate typical characteristics of system dynamics models and their use to understand system behavior. The example highlights basic structural features found in system dynamics models including stocks and flows, balancing and reinforcing feedback loops, nonlinearities, and time delays. The example shows how structure causes behavior and identifies several characteristic aspects of the behavior of dynamically complex systems, such as the basic dynamics of stocks and flows, dynamic equilibria, paradoxical patterns of behavior over time (e.g., better before worse), shifts in loop dominance, and tipping points. The paper closes with some thoughts on using system dynamics to improve military planning.
-
- Type:
- Document
- Date Created:
- 2008 July 20-2008 July 24
- Collection:
- System Dynamic Society Records
- Collecting Area:
- University Archives
- Collection ID:
- ua435
- Parent Record(s):
- 23d738ba88f8333bc39725f9cb5bd0b8, ce498623f0349395d0a141a0525190a0, and 6cbae5a21467df4434abbc87da443217
- Description:
- We develop a formal model of dynamic problem solving motivated by an example of doctors handling a medical emergency. The model links interpretation and choice, usually separated in the sensemaking and decision making literatures. Three insights emerge: (1) dynamic problem solving includes acting, interpreting, and cultivating diagnoses; (2) dynamic feedback among these processes opens and closes windows of adaptive problem solving; and (3) reinforcing feedback processes, usually considered dysfunctional, are essential for adaptive problem solving.
-
- Type:
- Document
- Date Created:
- 2008 July 20-2008 July 24
- Collection:
- System Dynamic Society Records
- Collecting Area:
- University Archives
- Collection ID:
- ua435
- Parent Record(s):
- 23d738ba88f8333bc39725f9cb5bd0b8, ce498623f0349395d0a141a0525190a0, and 6cbae5a21467df4434abbc87da443217
- Description:
- In recent years several scholars and practitioners have proposed that a combination of system dynamics and the resource-based view of the firm (RBV) can help to explain anomalies in firms competitive performance over time. For example why do some firms, despite initial success, subsequently falter and even fail spectacularly. This article provides a practical example based on the well-known rise and fall of People Express in the highly competitive US airline industry of the mid-1980s. The contribution of RBV and system dynamics to understanding the changing fortunes of the firm is discussed and also critiqued.
-
- Type:
- Document
- Date Created:
- 2008 July 20-2008 July 24
- Collection:
- System Dynamic Society Records
- Collecting Area:
- University Archives
- Collection ID:
- ua435
- Parent Record(s):
- 23d738ba88f8333bc39725f9cb5bd0b8, ce498623f0349395d0a141a0525190a0, and 6cbae5a21467df4434abbc87da443217
- Description:
- The scientific community agrees global climate change caused by anthropogenic sources of greenhouse gas emissions (GHG) is occurring, and the projected rise in average global temperatures as a result of climate change could lead to serious consequences for human health, economies and the environment. The transportation sector is a significant source of CO2 emissions, and in the United States accounts for 28 percent of GHG emissions. Because of transportations considerable contribution, the federal government and states have explored and continue to consider ways to lower CO2 emissions from this sector. Biofuels in particular are a popular option for addressing climate change and two main types of biofuels policies have received much focus recently for their potential to reduce GHG emissions from the transportation sector: the renewable fuels standard (RFS) and the low carbon fuels standard (LCFS). It is important to analyze and compare these two policies with regard to their potential contribution to the overarching goal of reducing CO2 emissions. By assessing the RFS and LCFS specifically for the state of Minnesota, this project seeks to address the question: How can Minnesota maximize the contribution of biofuels to CO2 emissions reductions through state-level policy?
-
- Type:
- Document
- Date Created:
- 2008 July 20-2008 July 24
- Collection:
- System Dynamic Society Records
- Collecting Area:
- University Archives
- Collection ID:
- ua435
- Parent Record(s):
- 23d738ba88f8333bc39725f9cb5bd0b8, ce498623f0349395d0a141a0525190a0, and 6cbae5a21467df4434abbc87da443217
- Description:
- The paper analyzes the geographical diffusion of system dynamics in academia using information on the affiliations of authors who have contributed to the System Dynamics Review. The paper develops and interprets a set of descriptive indicators that allow the identification of sustainable adoptions of system dynamics in a particular country. Longitudinal analyses indicate difficulties in the diffusion process and point at policies potentially advancing the further dissemination of SD.
-
- Type:
- Document
- Date Created:
- 2008 July 20-2008 July 24
- Collection:
- System Dynamic Society Records
- Collecting Area:
- University Archives
- Collection ID:
- ua435
- Parent Record(s):
- 23d738ba88f8333bc39725f9cb5bd0b8, ce498623f0349395d0a141a0525190a0, and 6cbae5a21467df4434abbc87da443217
- Description:
- In this work we develop a SD model for a make-to-order (MTO) three-stage capacitated production/inventory system. We employ a production order release mechanism affiliated with the automated pipeline inventory and order based production control system (APIOBPCS) policies family. The production rates at each stage are defined under alternative policies. One of the policies considers the human behavior in the decision making process. The robustness of the alternative policies is investigated through the dynamic response of the system under step and pulse changes in demand. Finally, the efficiency of the alternative policies is examined by means of six performance criteria.