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Abstract: Ice accretion of overhead conductors is a serious problem for power utilities. Among various de-icing approaches, short circuit based de-icing is one of the most frequently used ones. Since the short circuit based de-icing requires cumbersome and tricky operations, and some lines are taken out of service, pre-planned short circuit schemes are usually adopted in order to prevent mis-operation. Whereas, since some transmission lines might be tripped and system topology varies notably during ice storm, fast forming of short circuit de-icing scheme is not a simple task. Based on thorough investigation of pre-established de-icing schemes in Changsha power grid, rules to set up de-icing schemes are concluded. An expert system combining the power of graph theory has been developed in the paper to enumerate all the feasible de-icing routes. Thereafter, short circuit current and de-icing time of each route are calculated to single out candidate routes, and thus, dispatchers can form de-icing scheme at easy. [Copyright &y& Elsevier]

Abstract: Sustainable development is of great significance in rural areas of China, which are under coupled pressures of poverty reduction, environmental protection and economic development. In these areas, agriculture is the primary sector in supporting their economies, where a number of the relevant production and processing practices cause many adverse impacts on environment and ecosystem. This poses many challenges for decision makers in formulating sustainable development strategies without invoking potential controversies or objections from the public. In this study, a two-level expert system (TES) for facilitating the investigation of public’s perception towards sustainable development in rural areas was developed. Interactive relationships among objectives of socio-economic development and environmental protection, as well as the related policy implications and public responses, were comprehensively examined and incorporated within TES. A two-level system was particularly adopted for facilitating participation of various stakeholders, including decision makers and farmers. The Yongxin County of the Shanjianghu Region in Jiangxi Province, China was selected to demonstrate the applicability of the developed TES. A series of questionnaire surveys were conducted both for acquiring knowledge about the interrelationships among sustainable development, agricultural production, poverty reduction and environmental protection. Public’s perception towards various system components of rural sustainable development were efficiently acquired and analyzed. The results indicated that sustainable development would be very significant on rural areas in China. Also, public awareness to the concept and profile of rural sustainable development was still at a low level, especially for farmers. The developed TES can be not only used for acquiring knowledge of sustainable development, but also providing basic information for the formulation of relevant policies and strategies in rural areas of China. [Copyright &y& Elsevier]

A rule-based expert system has been built for selection of both retaining wall types and groundwater control methods in deep excavations in Wuhan city. For this expert system, a new type of generation rule is developed in which one condition is able to be defined with a “third state” that not only contributes directly to reaching the conclusion in a rule, but also factors into calculating the reliability of the conclusion. The traditional backward chaining technique has been improved to accommodate the change of a rule type and a fuzzy backward chaining method IRO has been established to increase reasoning flexibility. Using IRO as a fundamental element, it is convenient to form a complicated reasoning network in the inference engine. Finally, two knowledge bases are built from more than 100 case histories and other resources, and the new expert system proves to be effective in case studies. [Copyright &y& Elsevier]