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- Type:
- Document
- Date Created:
- 2006 July 23-2006 July 27
- Collection:
- System Dynamic Society Records
- Collecting Area:
- University Archives
- Collection ID:
- ua435
- Parent Record(s):
- f9377a3ac7b50b1fca5e04fb6d679ec2, 23d738ba88f8333bc39725f9cb5bd0b8, and 32937c7b43e3e015509bb71fd40d2054
- Description:
- Liberalisation of markets is supposed to be an adequate procedure to satisfy the worldwide demand for innovations. However, the transition from regulated markets to competition is a disequilibrium phenomenon and requires specific consideration of the appearing dynamics. We present in this paper a simple, yet general, model which is instrumental in understanding the likely market evolution during a liberalisation process. Furthermore, the developed System Dynamics-based model provides the possibility to simulate strategic decision-making in out-of-equilibrium markets caused by deregulation. The impacts on firm and market performance of a price-maker strategy, enabled through process innovation, on the one hand and a differentiation strategy on the other hand are discussed in details. The model is adapted to a goods market, albeit the presented implications have much wider use.
-
- Type:
- Document
- Date Created:
- 2006 July 23-2006 July 27
- Collection:
- System Dynamic Society Records
- Collecting Area:
- University Archives
- Collection ID:
- ua435
- Parent Record(s):
- f9377a3ac7b50b1fca5e04fb6d679ec2, 23d738ba88f8333bc39725f9cb5bd0b8, and 32937c7b43e3e015509bb71fd40d2054
- Description:
- As part of a project which deals with comprehensive free-flow toll systems for trucks and buses, a multi- agent based simulation model was developed. This model is used here to discuss the general development process for multi-agent based simulations which map real-world situations and whose results are the foundation for real-world decisions. It will be demonstrated that developing such models is a demanding task, requiring detailed understanding of the relevant reality and meticulous work. In addition findings from the model and their implication for planning and installing real world comprehensive truck toll systems will be outlined.
-
- Type:
- Document
- Date Created:
- 2006 July 23-2006 July 27
- Collection:
- System Dynamic Society Records
- Collecting Area:
- University Archives
- Collection ID:
- ua435
- Parent Record(s):
- f9377a3ac7b50b1fca5e04fb6d679ec2, 23d738ba88f8333bc39725f9cb5bd0b8, and 32937c7b43e3e015509bb71fd40d2054
- Description:
- The interaction between economic and ecological dynamic systems is analyzed with a multi-agent dynamic game of fishery management. Multiple actors (fishermen) harvest multiple fish types and adapt the amount and allocation of their investments to their value functions, which are given as net profits of the fish harvest sold for a market price. We introduce and compare two different decision rules in the competition of fishermen which both lead to a decline of fish stocks as well as profits for most fishermen. As an alternative, we introduce a cooperative approach to jointly set sustainable limits for total harvest and investment that are then distributed to the fishermen according to distribution rules. As the simulation shows, fish stocks and profits stabilize at significantly higher levels in the cooperative case, leading to a continuous accumulation of capital.
-
- Type:
- Document
- Date Created:
- 2006 July 23-2006 July 27
- Collection:
- System Dynamic Society Records
- Collecting Area:
- University Archives
- Collection ID:
- ua435
- Parent Record(s):
- f9377a3ac7b50b1fca5e04fb6d679ec2, 23d738ba88f8333bc39725f9cb5bd0b8, and 32937c7b43e3e015509bb71fd40d2054
- Description:
- This paper continues a line of work that took up previously published stock-and-flow thinking studies and proposed to apply the model of implicit learning to the case. According to this model, novices have to elaborate personal experience by following rules. After previous trials, a set of such rules is proposed together with a group of challenges that allow to apply and to learn them. A conceptual model for representing the rules, the challenges, the learners and their learning itinerary are proposed. Then, the design for an on-line system for publishing and working with challenges and to monitor progresses is introduced. This software system is currently under construction and first data from its use will be presented at the conference
-
- Type:
- Document
- Date Created:
- 2006 July 23-2006 July 27
- Collection:
- System Dynamic Society Records
- Collecting Area:
- University Archives
- Collection ID:
- ua435
- Parent Record(s):
- f9377a3ac7b50b1fca5e04fb6d679ec2, 23d738ba88f8333bc39725f9cb5bd0b8, and 32937c7b43e3e015509bb71fd40d2054
- Description:
- This paper suggests that the misperception of feedback individuals show may depend on the frame presented to them. A brief summary of Kahnemans work about heuristics is used to argue that the Beer Game may not be neutral: its very presentation may influence the cognitive processes and the observed performance. Some modifications to the Beer Game material and rules are proposed in order to make the feedback and delay structure more easy to grasp. Empirical work with the modified material is currently in progress.
-
- Type:
- Document
- Date Created:
- 2006 July 23-2006 July 27
- Collection:
- System Dynamic Society Records
- Collecting Area:
- University Archives
- Collection ID:
- ua435
- Parent Record(s):
- f9377a3ac7b50b1fca5e04fb6d679ec2, 23d738ba88f8333bc39725f9cb5bd0b8, and 32937c7b43e3e015509bb71fd40d2054
- Description:
- Though the size of System Dynamics models should be compact focusing on the main feedback loops determining system behavior one kind of model can become quite large: multi-national, multi-sectoral spatially differentiated models. The paper briefly presents such a model called ASTRA (=Assessment of Transport Strategies), which is developed in several versions over the past eight years. The purpose of the paper is to describe an approach how such a system dynamics model despite its size can be calibrated to make it applicable for Europeanwide policy analysis of transport policies. The approach is designed as a sequential process involving an au-tomated tool combining a C-coded steering programme with the Vensim® optimizer to enable calibration of large numbers of similar equations that only differ by their pa-rametrization.
-
- Type:
- Document
- Date Created:
- 2006 July 23-2006 July 27
- Collection:
- System Dynamic Society Records
- Collecting Area:
- University Archives
- Collection ID:
- ua435
- Parent Record(s):
- f9377a3ac7b50b1fca5e04fb6d679ec2, 23d738ba88f8333bc39725f9cb5bd0b8, and 32937c7b43e3e015509bb71fd40d2054
- Description:
- How long could an organization survive without its information systems working efficiently? Frequent changes of the systems to protect, significant delays between efforts and results, the large amount of involved variables and the difficulty to measure some of them make security management a challenge for current companies. Simulation models provide a virtual environment that can help analysing the dynamic balance between the affected key factors. These key factors include technical controls (Software and hardware elements to protect the system), formal controls (Procedures for guaranteeing an efficient use of technical controls) and security culture (Human factors that affect the compliance of the designed procedures).This paper presents a real modelling process, involving a university team and two companies. The paper includes information about the used methodology, the process and the preliminary results of the obtained model. This process has allowed concluding that the obtained benefits are very promising.
-
- Type:
- Document
- Date Created:
- 2006 July 23-2006 July 27
- Collection:
- System Dynamic Society Records
- Collecting Area:
- University Archives
- Collection ID:
- ua435
- Parent Record(s):
- f9377a3ac7b50b1fca5e04fb6d679ec2, 23d738ba88f8333bc39725f9cb5bd0b8, and 32937c7b43e3e015509bb71fd40d2054
- Description:
- System dynamic models are typically impossible to solve analytically and even hard to correctly simulate. This complexity is also true in equilibrium and stability analysis. This research deals with analytical and numerical phase plane analysis of such models. Example models chosen have no analytical time trajectory solutions; they are nonlinear and computationally stiff. In the study, two example models are analyzed; a prey-predator model and a competition model. Numerical phase plane constructions of these systems are first carried out. Then, analytical phase trajectories are obtained by using LambertW functions, implemented by Maple software. Numerical work is carried out by Stella simulation software, and by numerical algorithms in MAPLE. Comparisons between analytical and numerical phase trajectories are made and it is observed that significant discrepancies may exist. The study shows that, although analytical time trajectories are typically impossible to obtain, analytical phase trajectories offer important potential for system dynamics
-
- Type:
- Document
- Date Created:
- 2006 July 23-2006 July 27
- Collection:
- System Dynamic Society Records
- Collecting Area:
- University Archives
- Collection ID:
- ua435
- Parent Record(s):
- f9377a3ac7b50b1fca5e04fb6d679ec2, 23d738ba88f8333bc39725f9cb5bd0b8, and 32937c7b43e3e015509bb71fd40d2054
- Description:
- In this paper submitted to the special session on System Dynamics and Organizational Learning: purposes, practices and pitfalls, we describe a system dynamics intervention using the principles of Group Model Building to uncover the deep-seated issues in a long-standing problem area of an organization. In describing this intervention, we will outline how we used causal loop diagrams to represent the system in focus and identify leverage points for improvement. This intervention is positioned as part of an organizational capability-building program involving a university postgraduate degree. This paper will analyse our learning in the context of the research question outlined in the special session proposal.
-
- Type:
- Document
- Date Created:
- 2006 July 23-2006 July 27
- Collection:
- System Dynamic Society Records
- Collecting Area:
- University Archives
- Collection ID:
- ua435
- Parent Record(s):
- f9377a3ac7b50b1fca5e04fb6d679ec2, 23d738ba88f8333bc39725f9cb5bd0b8, and 32937c7b43e3e015509bb71fd40d2054
- Description:
- Building upon previous work in the field of system dynamics, a generic model of multiple improvement initiatives is outlined. The current model structure incorporates empirical data gathered by the author. The empirical data is taken from a large international survey of manufacturing plants and serves as calibration sets for several program implementation patterns. Statistical analyses and simulation experiments revealed noticeable preliminary results: (i) plants should strive for balanced implementation patterns that focus on multiple programs instead of favoring a single program. (ii) Plants should balance their implementation patterns according to the organizational and technological complexity of the improvement programs, i.e. that comparatively more efforts should be spent on more challenging improvement efforts. The value of the conducted approach lies (i) in the explicit investigation of the impact of different improvement programs (e.g. TQM, TPM, process automation, training) and (ii) in the integration of empirically gathered data.