Functional system dynamics

This thesis addresses the question how continuous components can be analyzed and described such that the resulting model can be used in a larger system for system\ud analysis and simulation. The question focusses very much on the treatment of a single component and its means to interact with its surroundings. The interaction\ud takes the form of the power variables of bond-graph modelling representing the action-reaction pair which product is the energy ow in and out of the system

Economic system dynamics

We provide the reader with a qualitative summary of the main ideas from econophysics and finance theory, starting with a thorough criticism of the standard ideas taught in typical economics textbooks. The emphasis is on the Galilean or physicists' approach to market synamics, as opposed to the standard nonempirical postulatory one.Utility; equilibrium; supply and demand curves; business cycles; market dynamics

Optimisation of system dynamics models

1. Definition of the Subject and Its Importance 2. Optimisation as calibration 3. Optimisation of performance (policy optimisation) 4. Examples of SD optimisation reported in the literature 5. Future directions in SD optimisation 6. Reference

Applying System Dynamics Approach to the Fast Fashion Supply Chain: Case Study of an SME in Indonesia

The fashion industry is the biggest contributor among the 14 creative industries in Indonesia. Nowadays many apparel companies are shifting toward the vertical integration. Since speed is everything to be successful in the apparel industry, fast fashion retailers must quickly respond to the market demand. This papers aims to develop a model of the supply chain of a small and medium scale enterprise (SME) of an apparel company in Indonesia and to propose a decision support system using System Dynamics (SD) and helps the management to identify the best business strategy. Simulated scenarios can help the management to identify the most appropriate policy to be applied in the future. Case study method was used in this research where data were collected from a typical fast fashion firm in Indonesia that produces its own wares ranging from raw materials to be ready-to-wear clothes, has three stores, a warehouse and is running online sales system. We analyses the result of many simulations in a fashion company from an operational point of view and from them we derive suggestions about the future business strategy in a small and medium fashion company in Indonesia

Development of Spatial-System Dynamics Model for Food Security Policy in Indonesia: a Generic Sub-Model Simulation

. The Indonesia has the immense geographic condition and heterogeneous condition, therefore food security issues could not be aggregated nationally, instead, they have to be described per region. In this paper, the region is defined as a province. Food security issues in every region are dynamic, and generated with complex system structure, will be described in the paper as follows. First, in order to have the comprehensive description of food security, we develop a new spatial system dynamics model that combines the concept of space and time. Previous spatial system dynamics methods could only describe the dynamics of the natural/physical system. The new spatial system dynamics proposed in this paper is designed to accommodate human decision for policy intervention. Then, we develop a decision support system, as follow. (1) After comparing characteristics of each province, we can identify the similarity of all province. We call the similarity as the generic model. (2). We propose a new method of spatial system dynamics that can accommodate the immense geographic condition and the heterogeneity. (3) By combining the generic model and the new method we propose a comprehensive model for decision support system in food security policy. Finally, from the experiments with a simulation of the comprehensive model, we could understand that a policy intervention of food security could give impact differently toward each region

Editorial: Food System Dynamics

The food system involves all actors, activities, resources, and environments that produce and provide food to people wherever they are. It serves basic human needs and is as such of core relevance for human survival. It is global in production, consumption, and environmental impacts. But it is also deeply rooted in the social, cultural, natural, political, and legal environments of society. It needs to serve a diversity of consumer needs and lifestyles and has to cope with an organizational complexity where, a.o. small scale farms or enterprises interact with globally active industry or retail groups and where rural sites of production are remote from the urban and ever growing centers of consumption.Editorial, Food Consumption/Nutrition/Food Safety,

System Dynamics Model and Policy Scenario Analyses on International Movements of Indonesian Scientists and Engineers

. The necessity to face technology challenges in industrialization in Indonesia causes the current condition to be not preferable. Conditions in higher education which relates closely to the research and development in Indonesia trigger questions of what future holds in Indonesia's technology development in the future. This paper looks back at the previous literatures on International movements of scientists and engineers abroad and proposes to apply a causal loop diagram model. This paper also analyzes the relationships based on Indonesia's context and set a parameter for each variable. The relationships were checked through interview with representation from Indonesian research institutions and Ministry of Foreign Affairs. The result of this paper confirms that the diagram is able to symbolize the circumstances in Indonesia's context. Second important finding is that based on simulation and policy scenarios implemented, the policy to increase the number of scholarships by the government is predicted as the most effective to all important parameters for future development in Indonesia in relation to education and technology development, which will eventually lead to economic development

Disentanglement by Dissipative Open System Dynamics

This paper investigates disentanglement as a result of evolution according to a class of master equations which include dissipation and interparticle interactions. Generalizing an earlier result of Di\'{o}si, the time taken for complete disentanglement is calculated (i.e. for disentanglement from any other system). The dynamics of two harmonically coupled oscillators is solved in order to study the competing effects of environmental noise and interparticle coupling on disentanglement. An argument based on separability conditions for gaussian states is used to arrive at a set of conditions on the couplings sufficient for all initial states to disentangle for good after a finite time.Comment: Paper in conjunction with and following on from P.J. Dodd and J.J. Halliwell: quant-ph/031206