We propose an advanced technique to obtain I-V curves in the first quadrant and the forth quadrant more accurately than by a conventional technique. In this study, we focus on the examination of the irradiance dependence to evaluate I-V curves of modules with different deterioration states. The I-V curves were swept in the first and the fourth quadrant obtained for different irradiances. Then, four constants of an equivalent circuit of the solar cells, i.e., series resistance (R_s), shunt resistance (R_sh), diode factor (n), and saturation current (A), were analyzed. Rs values were obtained for different irradiances and were stable for modules of the same model. R_s can be used to detect the failures and disconnections of modules in a string. Similarly, R_sh, n, and A can also serve as diagnostic indices. To examine the feasibility of using the four constants as diagnostic indices, the values of the four constants were examined for different irradiances.

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The Thai government has taken various political measures to promote the use of gasohol as an alternative to fossil-derived gasoline since 2003. The objective of the present study is to evaluate gasohol promotion policy of Thailand in the past from socio-economic and environmental perspectives. A modified input-output model is used to evaluate effects of an increase in gasohol use on the Thai economy from the three aspects, namely, domestic industry development, GHG emission, and employee income. The model is built on the Thai inputoutput table for the year 2005, by disaggregating the original sectors and adding new sectors related to gasohol production. The principal findings are as follows: first, an increase in gasohol use encourages the development of domestic industries through domestic inter-industrial linkages. Second, it decreases the GHG emission from the whole economy associated with a decrease in the use of gasoline; on the other hand, it should be also noted that the GHG emission caused by the gasohol production is not negligible. Third, the gasohol promotion policy increases employee income in the economy as a whole; more importance is that there is the potential increase in income of the rural households.

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Urban solid waste management is a complex issue and an integrated concept in the developing world. In this study, we proposed a model for handling solid waste generation, collection, separation, and reduction. The model would help to manage municipal waste using a spatial geodatabase for waste disposal site selection and the location of suitable composting sites. The selection of composting sites for the conversion of organic waste to compost can reduce the volume of wastes and enhance urban agriculture. In this research, several factors in waste generation, including primary waste-generating site selection, road networks, municipal waste sites in sensitive locations, reasons for illegal waste dumping sites, and waste segregation were included. The interrelationships between these factors and manual waste handling, unsuitable techniques, limited manpower, logistics, and landfill scarcity conditions were investigated. Multi-criteria analysis was applied for the identification of suitable waste sites and selection of suitable composting sites for the promotion of urban agriculture. Thus, the research suggested a participatory approach for the reduction of domestic waste by source-separation and waste-conversion techniques. To map and visualize variation, Geographic Information System (GIS) was used to show the waste collection scenario, including sensitive locations, simultaneously dealt with several factors that were considered in the planning of waste management in a part of Dhaka City. A suitable composting site must follow environmental safety criteria in isolating waste and converting organic waste to compost with no risk to the environment. On the basis of exclusionary criteria, decision factors, and standardization and weighting of factors, a final suitability map was produced and potential locations for composting were identified. One of the notable outcomes of this research work was investigation of the most suitable site for composting, so as to introduce and promote urban agriculture.

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