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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Using system dynamics principles for conceptual modelling of smart city development in South Africa

Das, D.K. January 2013 (has links)
Published Article / South African cities are in the process of transition in the changing scenario and need a change in the planning perspective for their sustainable development. The concept of smart city offers opportunities for such development to many middle sized cities of South Africa. Therefore, in this paper conceptual modelling for development of smart cities in South Africa is attempted based on systems concept. The conceptual models are built by using the principles of system dynamics methodology and based on causal feedback relationships among the various factors under different smart characteristics of a city such as, smart economy, smart people, smart governance, smart mobility, smart environment and smart living. The causal feedback loops and interrelationship among various parameters illustrate the dynamicity and influence of parameters on one another, which would able to assist in evolving plausible policy interventions for developing smart cities in South Africa. It is concluded that the modelling approaches presented here could guide the policy makers and city planners to evolve robust and responsive policy interventions for developing smart cities in the changing scenario.
2

Perspective impacts of information technology industry in development of Pune City in India

Das, D.K., Sonar, S.G. January 2013 (has links)
Published Article / The emergence of Information Technology (IT) is increasingly influencing the socio-economic and physical landscape of cities. It has also resulted in development of predominantly IT based industrial cities. These cities have the opportunities and challenges with respect to the development of their socioeconomic, infrastructural and environmental conditions because of the influence of the IT based industrial activities. This article therefore pertains to the analysis of the perspective impacts of IT industry and allied activities on the development of an emerging IT industrial activity based city. For this purpose, Pune, an emerging IT city in India was considered as a case study. Survey research methodology and a system dynamics modelling approach were employed to measure the influential socio-economic, infrastructural and environmental parameters of the city by considering the city as a system. This research shows that the location of IT industry and associated functions contribute significantly towards the socio-economic development of a city in terms of IT industry export, State Gross Domestic Product (SGDP), per capita SGDP, employment generation, to name some relevant aspects. However, there would be a reduction in satisfaction level of the infrastructure and an increase in environmental stress in the system, which needs strategic attention. Further, the model results and scenarios can facilitate evolving of feasible policy and strategic guidelines for the wholesome development of such cities.
3

Strategic risk management for tidal current and wave power projects

Bucher, Ralf January 2018 (has links)
Tidal current and wave power, as emerging forms of renewable generation, represent innovations that are confronted by significant technological and financial challenges. Currently, the marine energy sector finds itself in a decisive transition phase having developed full-scale technology demonstrators but still lacking proof of the concept in a commercial project environment. After the decades-long development process with larger than expected setbacks and delays, investors are discouraged because of high capital requirements and the uncertainty of future revenues. Although ideas for improving the investment climate can be found, there is a lack of well-founded arguments and coordinated strategies to work towards a breakthrough in the marine energy market. The objective of this research is to provide stakeholder-specific prioritised strategy options for de-risking the commercialisation of tidal current and wave power technologies. A key principle applied is to integrate a wide knowledge spectrum comprising the technology, policy and financing sectors and to compile the information in a holistic and transparent manner. To gain a broad understanding of the characteristics of presently ongoing marine energy activities and the correlated strategic planning, a comprehensive survey was conducted. Based on this multidisciplinary attempt, an all-encompassing appraisal was possible by avoiding over-concentration on stakeholder-specific views or interests. System dynamics modelling was employed to develop a series of cause-effect relationship diagrams of the key interactions and correlations in the field. It was revealed that the circular relationship between two major risks for array-scale projects - reliability and funding - requires coordinated action to overcome. As funding is necessary for improving system reliability (and vice-versa), showcasing 'array-scale success' was identified as the game-changing milestone towards commercial generation. Furthermore, it was found that a number of comparably competent manufacturing firms is required to implement major marine energy projects. This would result from fostering a multi-company market breakthrough concept, based on intensified knowledge sharing and trustful collaborative interaction between competitors. Additionally, effective separation of complexity into 'detail' and 'dynamically complex' constituents was found to be fundamental for identifying long-term, effective solutions. It is decisive to accept this primary classification, as measures appropriately applied on one type of complexity can be counterproductive if applied on the other. Most of the available planning tools and analytical methods do not address the management of dynamic complexity, necessary in innovative environments where flexibility and tolerance of vagueness are indispensable. Successful application of several strategies to deal with both types of complexity in comparable innovation-driven environments was considered suitable for de-risking the commercialisation of marine energy. The challenges for strategy-finding in a demandingly complex and increasingly dynamic environment are addressed in this research by exploiting a case-specific expert knowledge database. The structured information compression and subsequent strategy-finding process is realised based on calculated rankings of impact factors by systems dynamics software and substantiated by representative interview statements. The analysis makes use of multi-level expert knowledge and the application of a control-loop-based methods. The systems approach as applied in this research comprises the combination of interview-based (bottom-up learning) processes and the application of prioritised strategy options in the form of concerted management action (top-down planning). The approach of processing multi-level interview data by system dynamics modelling represents a powerful method to detect and assess ongoing developments and thus to advance strategy-finding. The systematic and unbiased approach to identify the top-level drivers for commercialising marine energy supports the long-term creation of investor confidence, based on a concept of transparency and credibility.
4

Advancing Sustainability in Tourism Destinations with a Complex Adaptive Systems Approach Based on Systems Dynamics Modelling

Karin Schianetz Unknown Date (has links)
This thesis analyses the potential of a complex adaptive systems (CASs) approach based on system dynamics modelling (SDM) to add value to the currently used assessment tools and monitoring practices for tourism sustainability in an effort to advance sustainable development in tourism destinations. While many different concepts and tools for the assessment of sustainability have developed, most of them do not take the complexity and dynamics of tourism destinations into account. It is argued in this thesis that these linear tools need to be complemented with new approaches that can deal with uncertainty, non-linearity and unexpected changes. New knowledge from ecosystem research, which is derived from complex systems theory, suggests that tourism destinations are indeed social-ecological systems, which need to be viewed and studied as CASs. In recent years tourism researchers have acknowledged the necessity to view tourism as a system with interconnected elements, and have discussed the unpredictability of these tourism systems. CASs approaches, which have been successfully applied by ecologists and economists in other areas, are indicated for tourism management, but have been rarely used in order to promote sustainable tourism development and planning. Appropriate methodologies and frameworks for the implementation of CASs approaches into the tourism context are still lacking. Therefore this thesis addresses the aforementioned challenges as follows: • A critical review of the concepts and tools currently used for the advancement and assessment of sustainability in tourism destinations is presented. The review evaluates the suitability of assessment tools for specific sites and situations, and develops guidelines for tool selection. It is concluded that for particular purposes linear assessment tools need to be combined or complemented with tools that can deal with complexity and dynamics. Tools covered include sustainability indicators, environmental impact assessment, life cycle assessment, environmental audits, ecological footprints, multi-criteria analysis and adaptive environmental assessment. • The use of sustainability indicator as one of the most promoted assessment tools for sustainable development in tourism destination is explored further. A systemic indicator system (SIS) methodology based on a CASs approach as an alternative to linear assessments is developed. This methodology is tested using a case study of a holiday eco-village near Lamington National Park in Queensland. The research findings suggest that the SIS has the potential to enhance system understanding and adaptive management of tourism destinations, and can foster collective learning processes amongst stakeholders. • A framework is developed for a Learning Tourism Destination (LTD) based on the concept of the Learning Organisation, and using SDM as a tool for strategic planning and the promotion of organisational learning. The concept of the LTD is discussed on the basis of 6 case studies, where SDM has been applied primarily for predictive reasons, and through evaluation of the potential of SDM as a tool for the implementation and enhancement of collective learning processes. The results reveal that SDM is capable of promoting communication between stakeholders and stimulating organisational learning. It is argued that the effectiveness of SDM may be greatly increased through incorporation in the foundation of an LTD. • A practical approach for the implementation of an LTD is presented. Preliminary results from a case study undertaken at the Ningaloo Coast in Western Australia are discussed. Surveys were conducted to verify if the LTD forms a useful framework for fostering consensus building, dialogue and collective learning processes amongst stakeholders. The preliminary results of the study suggest that the implementation of an LTD on the Ningaloo Coast will improve the capacity of the local industry to take more responsibility for the sustainable development, and thus has the potential to enable a more effective transition to sustainability in the region. Through its multi-methodological approach, this thesis demonstrates the importance of considering tourism destinations as CASs. New concepts and assessment tools for sustainable tourism are needed that acknowledge the complex and dynamic nature of tourism and tourism development. Together, the SIS methodology and the LTD framework provide an initial platform from which to conduct further research.
5

Advancing Sustainability in Tourism Destinations with a Complex Adaptive Systems Approach Based on Systems Dynamics Modelling

Karin Schianetz Unknown Date (has links)
This thesis analyses the potential of a complex adaptive systems (CASs) approach based on system dynamics modelling (SDM) to add value to the currently used assessment tools and monitoring practices for tourism sustainability in an effort to advance sustainable development in tourism destinations. While many different concepts and tools for the assessment of sustainability have developed, most of them do not take the complexity and dynamics of tourism destinations into account. It is argued in this thesis that these linear tools need to be complemented with new approaches that can deal with uncertainty, non-linearity and unexpected changes. New knowledge from ecosystem research, which is derived from complex systems theory, suggests that tourism destinations are indeed social-ecological systems, which need to be viewed and studied as CASs. In recent years tourism researchers have acknowledged the necessity to view tourism as a system with interconnected elements, and have discussed the unpredictability of these tourism systems. CASs approaches, which have been successfully applied by ecologists and economists in other areas, are indicated for tourism management, but have been rarely used in order to promote sustainable tourism development and planning. Appropriate methodologies and frameworks for the implementation of CASs approaches into the tourism context are still lacking. Therefore this thesis addresses the aforementioned challenges as follows: • A critical review of the concepts and tools currently used for the advancement and assessment of sustainability in tourism destinations is presented. The review evaluates the suitability of assessment tools for specific sites and situations, and develops guidelines for tool selection. It is concluded that for particular purposes linear assessment tools need to be combined or complemented with tools that can deal with complexity and dynamics. Tools covered include sustainability indicators, environmental impact assessment, life cycle assessment, environmental audits, ecological footprints, multi-criteria analysis and adaptive environmental assessment. • The use of sustainability indicator as one of the most promoted assessment tools for sustainable development in tourism destination is explored further. A systemic indicator system (SIS) methodology based on a CASs approach as an alternative to linear assessments is developed. This methodology is tested using a case study of a holiday eco-village near Lamington National Park in Queensland. The research findings suggest that the SIS has the potential to enhance system understanding and adaptive management of tourism destinations, and can foster collective learning processes amongst stakeholders. • A framework is developed for a Learning Tourism Destination (LTD) based on the concept of the Learning Organisation, and using SDM as a tool for strategic planning and the promotion of organisational learning. The concept of the LTD is discussed on the basis of 6 case studies, where SDM has been applied primarily for predictive reasons, and through evaluation of the potential of SDM as a tool for the implementation and enhancement of collective learning processes. The results reveal that SDM is capable of promoting communication between stakeholders and stimulating organisational learning. It is argued that the effectiveness of SDM may be greatly increased through incorporation in the foundation of an LTD. • A practical approach for the implementation of an LTD is presented. Preliminary results from a case study undertaken at the Ningaloo Coast in Western Australia are discussed. Surveys were conducted to verify if the LTD forms a useful framework for fostering consensus building, dialogue and collective learning processes amongst stakeholders. The preliminary results of the study suggest that the implementation of an LTD on the Ningaloo Coast will improve the capacity of the local industry to take more responsibility for the sustainable development, and thus has the potential to enable a more effective transition to sustainability in the region. Through its multi-methodological approach, this thesis demonstrates the importance of considering tourism destinations as CASs. New concepts and assessment tools for sustainable tourism are needed that acknowledge the complex and dynamic nature of tourism and tourism development. Together, the SIS methodology and the LTD framework provide an initial platform from which to conduct further research.
6

Indoor overheating risk : a framework for temporal building adaptation decision-making

Gichuyia, Linda Nkatha January 2017 (has links)
Overheating in buildings is predicted to increase as a result of a warming climate and urbanisation in most cities. With regards to responding to this challenge, decision makers ranging from_ design teams, local authorities, building users, national programs and market innovators; and during the different stages of a building’s service life, want to know a few pertinent matters: What space characteristics and buildings are at a higher risk and by how much?; What are the tradeoffs between alternative design and/or user-based actions?; What are the likely or possible consequences of their decisions?; What is the impact of climate change to indoor overheating?; among other decision support questions. However, such decision appraisal information still remains buried and dispersed in existing simulation models, and empirical studies, and not yet been clearly articulated in any existing study or model. Especially decision support information articulated in a way that gives each decision maker maximum capacity to anticipate and respond to thermal discomfort in different spaces and through the lifetime of a building. There is a need for an integrated and systematic means of building adaptation decision-support, which provides analytical leverage to these listed decision makers. A means that: 1) assimilates a range of indoor thermal comfort's causal and solution space processes; 2) reveals and enhances the exploration of the space and time-dependent patterns created by the dynamics of the indoor overheating phenomenon through time; and one that 3) imparts insight into decision strategy and its synthesis across multiple decision makers. This study recognises the lack of an overarching framework attending to the listed concerns. Therefore, the key aim of this thesis is to develop and test a building adaptation decision-support framework, which extends the scope of existing frameworks and indoor overheating risk models to facilitate trans-sectional evaluations that reveal temporal decision strategies. The generic framework frames a multi-method analysis aiming to underpin decision appraisal for different spaces over a 50 to 100-year time horizon. It constitutes an underlying architecture that engages the dimensions of decision support information generation, information structuring, its exploration and dissemination, to ease in drawing decision strategy flexibly and transparently. The multi-method framework brings together: 1) Systems thinking methods to a) facilitate the systematic exposure of the elements that shape indoor overheating risk, and b) reveal the processes that shape multi-stakeholder decision-making response over time; 2) The use of normative, predictive and exploratory building scenarios to a) examine the overheating phenomenon over time, and b) as a lens through which to explore the micro-dynamics brought about by aspects of heterogeneity and uncertainty; and 3) The application of both computational and optimization techniques to appraise potential routes towards indoor thermal comfort over an extended time scale by a) tracking shifts in frequency, intensity and distribution of indoor overheating vulnerability by causal elements over time and space; and b) tracking shifting optima of the heat mitigation solution space, with respect to time, climate futures, heterogeneity of spaces, and due to thermal comfort assumptions. The framework’s potential has been demonstrated through its application to office buildings in Nairobi.
7

Reluctantly Virtual : Modelling Copyright Industry Dynamics

Wikström, Patrik January 2006 (has links)
<p>During the evolution of the music industry, developments in the media environment have required music firms to adapt in order to survive. Changes in broadcast radio programming during the 1950s; the Compact Cassette during the 1970s; and the deregulation of media ownership during the 1990s are all examples of changes which have heavily affected the music industry. This study explores similar contemporary dynamics, examines how decision makers in the music industry perceive and make sense of the developments, and reveals how they revise their business strategies, based on their mental models of the media environment.</p><p>A qualitative system dynamics model is developed in order to support the reasoning brought forward by the study. The model is empirically grounded, but is also based on previous music industry research and a theoretical platform constituted by concepts from evolutionary economics and sociology of culture. The empirical data primarily consist of 36 personal interviews with decision makers in the American, British and Swedish music industrial ecosystems. The study argues that the model which is proposed, more effectively explains contemporary music industry dynamics than music industry models presented by previous research initiatives.</p><p>Supported by the model, the study is able to show how “new” media outlets make old music business models obsolete and challenge the industry’s traditional power structures. It is no longer possible to expose music at one outlet (usually broadcast radio) in the hope that it will lead to sales of the same music at another (e.g. a compact disc).</p><p>The study shows that many music industry decision makers still have not embraced the new logic, and have not yet challenged their traditional mental models of the media environment. Rather, they remain focused on preserving the pivotal role held by the CD and other physical distribution technologies.</p><p>Further, the study shows that while many music firms remain attached to the old models, other firms, primarily music publishers, have accepted the transformation, and have reluctantly recognised the realities of a virtualised environment.</p>
8

Reluctantly Virtual : Modelling Copyright Industry Dynamics

Wikström, Patrik January 2006 (has links)
During the evolution of the music industry, developments in the media environment have required music firms to adapt in order to survive. Changes in broadcast radio programming during the 1950s; the Compact Cassette during the 1970s; and the deregulation of media ownership during the 1990s are all examples of changes which have heavily affected the music industry. This study explores similar contemporary dynamics, examines how decision makers in the music industry perceive and make sense of the developments, and reveals how they revise their business strategies, based on their mental models of the media environment. A qualitative system dynamics model is developed in order to support the reasoning brought forward by the study. The model is empirically grounded, but is also based on previous music industry research and a theoretical platform constituted by concepts from evolutionary economics and sociology of culture. The empirical data primarily consist of 36 personal interviews with decision makers in the American, British and Swedish music industrial ecosystems. The study argues that the model which is proposed, more effectively explains contemporary music industry dynamics than music industry models presented by previous research initiatives. Supported by the model, the study is able to show how “new” media outlets make old music business models obsolete and challenge the industry’s traditional power structures. It is no longer possible to expose music at one outlet (usually broadcast radio) in the hope that it will lead to sales of the same music at another (e.g. a compact disc). The study shows that many music industry decision makers still have not embraced the new logic, and have not yet challenged their traditional mental models of the media environment. Rather, they remain focused on preserving the pivotal role held by the CD and other physical distribution technologies. Further, the study shows that while many music firms remain attached to the old models, other firms, primarily music publishers, have accepted the transformation, and have reluctantly recognised the realities of a virtualised environment.
9

Asset Management in Electricity Transmission Enterprises: Factors that affect Asset Management Policies and Practices of Electricity Transmission Enterprises and their Impact on Performance

Crisp, Jennifer J. January 2004 (has links)
This thesis draws on techniques from Management Science and Artificial Intelligence to explore organisational aspects of asset management in electricity transmission enterprises. In this research, factors that influence policies and practices of asset management within electricity transmission enterprises have been identified, in order to examine their interaction and how they impact the policies, practices and performance of transmission businesses. It has been found that, while there is extensive literature on the economics of transmission regulation and pricing, there is little published research linking the engineering and financial aspects of transmission asset management at a management policy level. To remedy this situation, this investigation has drawn on a wide range of literature, together with expert interviews and personal knowledge of the electricity industry, to construct a conceptual model of asset management with broad applicability across transmission enterprises in different parts of the world. A concise representation of the model has been formulated using a Causal Loop Diagram (CLD). To investigate the interactions between factors of influence it is necessary to implement the model and validate it against known outcomes. However, because of the nature of the data (a mix of numeric and non-numeric data, imprecise, incomplete and often approximate) and complexity and imprecision in the definition of relationships between elements, this problem is intractable to modelling by traditional engineering methodologies. The solution has been to utilise techniques from other disciplines. Two implementations have been explored: a multi-level fuzzy rule-based model and a system dynamics model; they offer different but complementary insights into transmission asset management. Each model shows potential for use by transmission businesses for strategic-level decision support. The research demonstrates the key impact of routine maintenance effectiveness on the condition and performance of transmission system assets. However, performance of the transmission network, is not only related to equipment performance, but is a function of system design and operational aspects, such as loading and load factor. Type and supportiveness of regulation, together with the objectives and corporate culture of the transmission organisation also play roles in promoting various strategies for asset management. The cumulative effect of all these drivers is to produce differences in asset management policies and practices, discernable between individual companies and at a regional level, where similar conditions have applied historically and today.
10

Nutrient And Pathogen Removal In A Subsurface Upflow Wetland System Using Green Sorption Media

Xuan, Zhemin 01 January 2009 (has links)
Due to environmental health and nutrient impact concerns, the conventional on-site sewage collection, treatment, and disposal systems are no longer able to meet the nutrient reduction requirements for wastewater effluent and may represent a large fraction of pollutant loads. The loads include not only nitrogen (N) and phosphorus (P), but also pathogens such as fecal coliform and E. coli which indicate the presence of other disease-causing bacteria flowing into aquatic system that adversely affect public health. A subsurface upflow wetland, which is an effective small-scale wastewater treatment system with low energy and maintenance requirements and operational costs, fits the current nutrient and pathogen removal situation having received wide attention throughout the world. Within this research study, a subsurface upflow wetland system (SUW), including four parallel SUW (three planted versus one unplanted), were constructed as a key component of the septic tank system receiving 454 liters per day (120 GPD) influent using the green sorption media along with selected plant species. It was proved effective in removing both nutrients and pathogens. During a one month test run, the planted wetlands achieved a removal efficiency of 84.2%, 97.3 %, 98.93 % and 99.92%, compared to the control wetland, 10.5%, 85.7 %, 99.74 % and 100.0 %, in total nitrogen (TN), total phosphorus (TP), fecal coli and E.Coli, respectively. Denitrification was proved to be the dominant pathway for removing N as evidenced by the mass balance and real-time PCR analyses. A simplified compartmental dynamics simulation model of constructed subsurface upflow wetlands was also developed to provide a dependable reference and tool for design of constructed subsurface upflow wetland.

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