Browsing by Author "Pan, Tze-Chin"

Now showing 1 - 5 of 5

An environmental sustainability based budget allocation system for regional water quality management
(2009-02-01)
Kao, Jehng-Jung
;
Pan, Tze-Chin
;
Lin, Chin-Min
;
環境工程研究所
;
Institute of Environmental Engineering
A budget allocation system for regional water quality management to achieve environmental sustainability was developed in this study to assist a local authority with making appropriate budget allocations for improving Regional Water Environmental Sustainability (RWES) in ail efficient manner. The system consists of visions and goals, RWES indicators, and ail analysis of budget allocation versus RWES. Visions and goals define task priorities for improving water environmental sustainability. Indicators are used to measure the progress of related tasks toward RWES goals. These indicators are classified by the Driving Force-State-Response (DSR) framework to facilitate the analysis of relationships among indicators. Linkages between budget allocation And indicators tire also analyzed, and (lie result is Used to assess whether the available budget is allocated properly to raise the RWES. The applicability of the system is demonstrated by a case study involving a local environmental protection authority. (C) 2008 Elsevier lid. All rights reserved.
Effective solar radiation based benefit and cost analyses for solar water heater development in Taiwan
(2012-05-01)
Pan, Tze-Chin
;
Kao, Jehng-Jung
;
Wong, Chih-Po
;
環境工程研究所
;
Institute of Environmental Engineering
To reduce greenhouse gases emissions, promoting solar water heaters (SWHs) has become an essential national policy in Taiwan. To implement this policy effectively, the applicability of SWHs in different regions must be analyzed. Previous studies generally performed SWH benefit-cost analyses based on total annual solar radiation; however, this method may overestimate energy production benefits because, for an SWH, the solar energy captured today cannot be preserved. Therefore, this study proposes the concept of effective solar radiation (ESR), which is based on potential heat output estimated using tap water temperature and solar radiation in each region. The benefits of SWHs are then assessed based on the number of effective days and ESR, instead of using total annual solar radiation. A procedure is established to evaluate the applicability of SWHs in each region based on proposed benefit-cost analyses. Possible outcomes of a national SWH program are estimated. The sensitivities of essential factors, including collector efficiency, installation cost, and discount rate, are also analyzed. Analytical results show that the ratios of ESR to total annual solar radiation for regions in Taiwan are about 82-89%. The payback periods vary at 6-15 years for different regions and heater types being replaced. The national program is expected to reduce greenhouse gases emissions by approximately 150,000 tons eCO(2) annually. (C) 2012 Elsevier Ltd. All rights reserved.
GA-QP Model to Optimize Sewer System Design
(2009-01-01)
Pan, Tze-Chin
;
Kao, Jehng-Jung
;
環境工程研究所
;
Institute of Environmental Engineering
Sanitary sewer systems are fundamental and expensive facilities for controlling water pollution. Optimizing sewer design is a difficult task due to its associated hydraulic and mathematical complexities. Therefore, a genetic algorithm (GA) based approach has been developed. A set of diameters for all pipe segments in a sewer system is regarded as a chromosome for the proposed GA model. Hydraulic and topographical constraints are adopted in order to eliminate inappropriate chromosomes, thereby improving computational efficiency. To improve the solvability of the proposed model, the nonlinear cost optimization model is approximated and transformed into a quadratic programming (QP) model. The system cost, pipe slopes, and pipe buried depths of each generated chromosome are determined using the QP model. A sewer design problem cited in literature has been solved using the GA-QP model. The solution obtained from the GA model is comparable to that produced by the discrete differential dynamic programming approach. Finally, several near-optimum designs produced using the modeling to generate alternative approach are discussed and compared for improving the final design decision.
Inter-generational equity index for assessing environmental sustainability: An example on global warming
(2009-07-01)
Pan, Tze-Chin
;
Kao, Jehng-Jung
;
環境工程研究所
;
Institute of Environmental Engineering
Inter-generational equity is essential for environmental sustainability. The current generation inherits an environment with a certain quality from the previous generation. The impact on the environment gradually exacerbates and accumulates over a period of time between two generations. However, currently there is no index available to assess inter-generational equity. Generally a typical environmental index is established to represent the environmental status in a specific year. This kind of index, although it presents the annual environmental variation, does not reflect the degree of change in environmental sustainability between two generations. Therefore, an inter-generational equity index (IGEI) and an endowment equation to examine the temporal trend of the changing environment are proposed for assessing inter-generational equity. To demonstrate the applicability of the endowment equation, an IGEI was established to assess the inter-generational equity of global warming. The global warming IGEI evaluates the status between two generations based on three sub-indexes; CO(2) emission, loss due to climate disasters, and the size of the existing forest area. The pressure-state-response (PSR) framework was adopted to explain the causal relationship between these three sub-indexes. According to the endowment rate determined by the proposed equation for each sub-index, the increase in CO(2) emission from 1980 to 2000 shows an obviously inequitable pattern between generations. Subsequently, the loss due to climate disasters between generations was also more serious. The size of the forest area, an important factor for reducing the impact of global warming, is unfortunately also decreasing significantly between generations. Using the endowment rate determined by the proposed endowment equation, the evaluation of the inter-generational equity is made possible and is demonstrated by the IGEI established for global warming. (C) 2008 Elsevier Ltd. All rights reserved.
Performance assessment for municipal solid waste collection in Taiwan
(2011-04-01)
Huang, You-Ti
;
Pan, Tze-Chin
;
Kao, Jehng-Jung
;
環境工程研究所
;
Institute of Environmental Engineering
Collecting municipal solid waste (MSW) is a major and expensive task for local waste management authorities, thus efficient MSW collection is a necessity. This study presents a procedure for developing an aggregate indicator (AI) to assess MSW collection efficiency based on multiple factors. The applicabilities of various key performance indicators (KPIs) are evaluated based on five selection criteria, and five KPIs are chosen to form the AI. The relative efficiencies of local MSW collection services are analyzed by the data envelopment analysis (DEA) method. A set of common weights for all five KPIs is then generated based on DEA results and four selection rules by modifying a previous approach. Finally, the proposed AI is applied to assess the MSW collection services provided by 307 local governments in Taiwan, and associated results are compared and discussed. (C) 2010 Elsevier Ltd. All rights reserved.