提高中压配电网供电可靠性的措施及其成本/效益分析研究

对配电网可靠性评估的故障遍历方法和利用故障遍历事件集搜寻薄弱环节的方法进行了简要说明,而得到电网薄弱环节后就可制定相应的改进措施。为了对改进的措施进行评估,提出了因提高电网可靠性而发生的成本以及产生的效益的概念公式,在综合分析两者的基础上,引入了成本/效益比的概念来制定评价电网改造方案可行性和最优性的判据。最后对我国江西省某地区的县级实际中压配电网从四个方面提出了改进措施,同时利用上述判据对改进措施进行评估并得到最终的改进方案。

治疗精神分裂症的成本/效益分析

本文从临床疗效、耐受性、生活质量、成本几个方面 ,比较了几种常用抗精神病药物的成本 /效益研究资料 ,提出临床医生在作出精神分裂症的治疗决策时 ,应从上述多个方面权衡药物的成本 /效益。

支线机场GNSS非精密进近的成本/效益分析法

全球导航卫星系统 (GNSS)是当今民航导航技术发展的应用趋势。针对中小支线机场 ,给出GNSS仪表非精密进近与传统陆基导航设施下的仪表非精密进近的成本 /效益分析方法。详细讨论了GNSS非精密进近的投资建设成本及其相对于传统陆基导航设施下的仪表非精密进近程序的经济效益增长值的计算方法。

基于多指标效能分析的分布式潮流控制器选址定容优化策略

针对统一潮流控制器的推广受制于其可靠性及制造成本的问题,分布式潮流控制器(DPFC)应运而生,文中详细论述了DPFC的拓扑结构与工作原理,并对DPFC的特点及优势进行了分析。考虑到DPFC在电网中的安装位置及接入容量会直接影响其控制效能的发挥,制定了基于多指标效能分析的DPFC选址定容两阶段优化策略。首先,基于DPFC对系统潮流均衡的影响程度确定最优安装地点,然后再应用经济性成本/效益分析进行容量的优化。在IEEE 30节点系统中进行DPFC的优化配置以验证策略的可行性与有效性,仿真结果表明DPFC接入系统后能够有效改善电网多方面的效能。

分布式光伏发电并网的成本效益分析

近年来,由于大力发展经济导致自然资源濒临匮乏,这种情况给新时期经济发展造成阻碍之后,人们逐渐对绿色发展理念引起重视,倡导可再生能源为合理解决经济发展的一种重要措施。而光伏发电站的建设,主要是用太阳能发电,供给人们电量,满足人们用电需求,具有节能环保作用。文章主要阐述当前光伏发电运营模式,对其投入成本和产生效益进行分析,对光伏发电并网方案进行研究。

电力市场运营环境下配电网改造风险控制

电力市场环境下,供电公司是一个独立的、自负盈亏的经营主体,不仅需要考虑配电网的安全性,而且还需要考虑它的经济性,因此研究供电公司配电网改造的风险评估具有一定的实际意义。本文首先采用成本收益分析法对供电公司配电网改造的成本和收益进行分析,考虑了配电网改造后所带来的供电可靠性收益和减少可中断电价赔偿的收益;其次采用概率统计法对减少中断电量的不确定性和提高供电可靠性的不确定性问题进行分析,计算其减少的可中断赔偿效益和可靠性效益;最后根据用户用电量的分布构建配电网改造方案的风险评估模型,为供电公司提供一定参考。同时也为电力企业的正常运营奠定理论基础。

配电网可靠性改造项目实施顺序优化

配电网可靠性改造主要通过增加配电网的联络点和提高网架转供电能力、合理优化线路分段、应用故障指示器和智能开关、架空线更换绝缘导线等项目,从硬件配置方面提升供电可靠性。考虑到资金及人力等的限制,各改造项目只能分批有序实施,为使有限资金在最短时间内得到最大的可靠性效益回报,有必要对项目实施的顺序进行优化。以海南实际配电线路为案例,提出一种应用可靠性计算和成本/效益分析来进行配电网可靠性改造项目实施顺序优化的方法,并通过计算结果表明所提方法的实效性和可行性。

系统集成在工业控制中的应用

对工业控制系统逻辑控制语言的设计提出一个实用合理的面向数据流的方法 。

Cost-benefit analysis of esophageal cancer endoscopic screening in high-risk areas of China

AIM:To estimate the cost-benefit of endoscopic screening strategies of esophageal cancer(EC)in high-risk areas of China. METHODS:Markov model-based analyses were conducted to compare the net present values(NPVs)and the benefit-cost ratios(BCRs)of 12 EC endoscopic screening strategies.Strategies varied according to the targeted screening age,screening frequencies,and follow-up intervals.Model parameters were collected from population-based studies in China,published literatures,and surveillance data. RESULTS:Compared with non-screening outcomes,all strategies with hypothetical 100 000 subjects saved life years.Among five dominant strategies determined by the incremental cost-effectiveness analysis,screening once at age 50 years incurred the lowest NPV(international dollar-I$55 million)and BCR(2.52).Screening six times between 40-70 years at a 5-year interval[i.e., six times(40)f-strategy]yielded the highest NPV(I$99 million)and BCR(3.06).Compared with six times(40)fstrategy,screening thrice between 40-70 years at a 10-year interval resulted in relatively lower NPV,but the same BCR. CONCLUSION:EC endoscopic screening is cost-beneficial in high-risk areas of China.Policy-makers should consider the cost-benefit,population acceptance,and local economic status when choosing suitable screening strategies.

Cost effectiveness analysis of population-based serology screening and ^(13)C-Urea breath test for Helicobacter pylori to prevent gastric cancer:A markov model

AIM:To compare the costs and effectiveness of no screening and no eradication therapy, the population- based Helicobacter pylori (H pylori) serology screening with eradication therapy and 13C-Urea breath test (UBT) with eradication therapy. METHODS:A Markov model simulation was carried out in all 237 900 Chinese males with age between 35 and 44 from the perspective of the public healthcare provider in Singapore. The main outcome measures were the costs, number of gastric cancer cases prevented, life years saved, and quality-adjusted life years (QALYs) gained from screening age to death. The uncertainty surrounding the cost-effectiveness ratio was addressed by one-way sensitivity analyses. RESULTS:Compared to no screening, the incremental cost-effectiveness ratio (ICER) was $16 166 per life year saved or $13 571 per QALY gained for the serology screening, and $38 792 per life year saved and $32 525 per QALY gained for the UBT. The ICER was $477 079 per life year saved or $390 337 per QALY gained for the UBT compared to the serology screening. The cost- effectiveness of serology screening over the UBT was robust to most parameters in the model. CONCLUSION:The population-based serologyscreening for H pylori was more cost-effective than the UBT in prevention of gastric cancer in Singapore Chinese males.

Cost-benefit timing for applying slurry seal on actual roadway tests in China

Determining the optimal timing is the core of preventive maintenance. Highway agencies always face with the challenge of determining optimal timing for preventive maintenance, particularly in China where there are no condition indicators designed for determining adequate timing for applying preventive maintenance and little literature relating to the development of pavement performance. This work presented the indicators, including crack ratio （Rc）, rutting depth （DR）, international roughness index （IIR） and sideway force coefficient （CsF） to determine the adequate timing for preventive maintenance in China. The proper ranges of each indicator to apply to preventive maintenance were then recommended. They are 0.28%-1.4% for Rc, 10-15 mm for DR, 1.97-3.5 for lrR, 40--50 for CSF. Based on pavement condition survey data collected on the test roads in Hebei Province, China, on the application of slurry seal at different timings, the pavement performance was established and the adequate timings for applying slurry seal was studied. Based on benefit-cost analysis, it is suggested that the fourth year is the optimal timing for applying slurry seal based on the condition in China. A framework is established to determine the adequate timings of applying other preventive maintenance methods.

Cost estimation and control of colorectal cancer screening

Objective:The aim of our study was to estimate the cost of colorectal cancer screening and to provide evidence for the cost control of colorectal cancer screening among general population in rural area of China.Methods:We determined the net cost for colorectal cancer mass-screening in Jiashan County,and evaluated the cost-benefit and cost effectiveness.Results:The compliance rate of primary screening and intensive screening were 84.6% and 78.7%,respectively.In primary screening,the average cost for each individual was 27.2 yuan,and the average cost for identifying one high-risk individual was 180.5 yuan.The mean cost to diagnose one colorectal cancer patient was 42963.3 yuan.As for identification of adenoma,the average cost for each case was 4384.0 yuan.Based on the calculation,the average cost of reducing one colorectal cancer patient was 12768 yuan by conducting the mass-screening protocol.Conclusion:It was beneficial to do the cost-benefit analysis of colorectal cancer screening in area of high incidence.Based on the results of cost-benefit analysis,more efforts should be made to reduce the cost and to improve the efficiency of the colorectal cancer screening.

A Cost-Benefit Analysis of China＇s Trade Relations With Sub-Saharan Africa

Trade and economic relations between China and Africa have a protracted history and have developed incrementally over the course of time. Consequently, increasing numbers of Chinese businesses and entrepreneurs have sought partnerships with African companies with the aim of establishing strategic partnerships, collaborations, and joint ventures. In recent years, these Sino-African trading relations have been the subject of consistent debate and scrutiny, attracting positive and negative analyses from scholars and practitioners across disciplines. Some studies questioned China＇s motives in Africa＇s markets, and others viewed with suspicion the structure of Sino-Africa＇s bilateral trading engagements. Conducting an extensive literature survey of related sources and employing content analysis of recent and current data （2000-2009）, the paper examined institutional and academic publications pertaining to Sino-African relationship. It determines imbalance in the structure of Sino-African bilateral trade, negative impact on domestic economic development, and competitive disadvantage in African marketplaces. Policy implications of these findings were provided as well as recommendations for mutual trade benefits and global strategic investments

A Study on Additional Electric Energy Accommodation of Three Gorges Hydropower Station

Considering the additional electric energy generated after the full operation of the underground hydropower station, the electric energy accommodation of the Three Gorges Project （TGP） is reviewed. It is .focused on the additional electricity accommodation, based on the research at the earl）, stage. The electric energ）, accommodation solutions ate recommended as that. based on the cost-benefit analysis of the power distribution area, the additional electric energy of the Three Gorges should be given ptqority to meet the needs at the supply end of Hubei and Chongqing. The results of this research has a reference value on the implementation of the Three Gorges electric power accommodation, after the further optimization of the transmission curves in both wet and dry seasons.

Determining Cost-Efficiency and Regulation Policy for Water Transfer of Lake Balaton by Stochastic Dynamic Programming

The present research is based upon a comprehensive survey which discusses the slightly tolerable water level of Balaton between 2000 and 2003. The low water level of the extreme period caused considerable problems in recreation. Our goal was to investigate the possible water transfer policies and the water level regulation policy of Lake Balaton by applying the dynamic programming of Markov chains. This iteration supports the cost-benefit analysis of different scenarios and also provides information about the best water governing policy. As a basis of our scientific analysis, Markov chains were created by ARMA （autoregressive moving average） synthetic data generator. Profit was joined to each transition-probability for the economic analysis. In our case the profit was negative, because the harmful effects of the low water level should be estimated, which is based on the calculated willingness-to-pay for improving the water quality of Lake Balaton. In addition, the profit includes the cost of different water supplement scenarios. After computer programming, the method proved to be an efficient tool to buttress the cost-benefit analysis of water supplement scenarios. The result highlights the importance of further climate change monitoring. Calculation confirmed water transfer to be cost-effective, yet scenarios with less ecological risk are also effective, thus preferable.

A Comprehensive Audit of Corporate Social Responsibility

As enterprises expand globally, the social value of their operations is assessed on the full range of their contribution to society. Enterprises must be profitable to succeed, but they also should strategically align their operations so far as feasible and sustainable in order to address related social needs. This alignment includes not only the beneficial design and quality of goods and services an enterprise produces, but also enhancing the beneficial effects that its full range of business processes, systems, and practices have on society. A comprehensive enterprise corporate social responsibility （CSR） audit is based on two comprehensive social systems models---one of society as a whole and another of the corporate organization. By juxtaposing these two models--which are mirror images of each other--an enterprise can identify various points where its activities intersect with relevant social needs and can configure its operations so far as feasible to alleviate pressing social issues. Using a comparative cost-benefit analysis, the enterprise determines which systems, processes, and activities need to configure or adapt in order to better address the societal needs that are most critical for its success. They may require the enterprise to re-design products or services, develop new activities or desist in others, or reconfigure processes or systems. Thus, enterprises must decide which options are most feasible in light of the societal benefit they are likely to produce. As creatures of society, enterprises have much to gain by strengthening civil society and addressing its most pressing needs whenever possible within the limits of its commercial mission. What action to take depends upon the firm＇s cost-benefit analysis.

An assessment of Charter airline benefits for Port Elizabeth and the Eastern Cape

Tourism is becoming a vital component for economic development in South Africa. The income generated by the tourism industry is about 6% of the GDP, which is significant but still falls short of the goal set by the White Paper on Tourism in 2000. In the light of South Africa hosting the 2010 Football World Cup, it is important to identify ways of sustainable tourism development that would continue to increase the benefits to the economy long after the event＇s over. The main objective of the research was to explore an idea for increasing the level of tourist income generated in the Port Elizabeth （Eastern Cape） area. The idea was researched by means of conducting a cost-benefit analysis of two tourist related projects. These projects would introduce Charter airline services between Europe and Port Elizabeth. A second objective was to identify constraints on the project or market failures which would prevent their implementation. The economic theory behind the operation of an airline showed that lease costs and aeroplane operating costs are the two most important factors determine Charter airline＇s profitability. In order to offset these costs, airlines must achieve high passenger load factors. Charter airlines have the advantage over scheduled airlines, in that they will only fly if a minimum level of people has pre-booked seats. Two aeroplanes were chosen for comparison purpose： an Airbus A 340-300 and a Boeing 767-300ER. The private benefits calculated were based on load factors between 80 and 95 percent for ticket prices of USD 667 and USD 773. In addition, to private costs and benefits, social benefits were also estimated in the form of additional secondary revenue generated. With the introduction of net social benefits, both projects become profitable. A 50 percent substitution of revenue generated by the Charter tourists reduces the profits for the both projects drastically. A project based on a Boeing 767-300ER is the most efficient project as it has the highest NPV and BCR values. A reduction in the lease cost of the Airbus 340-300 could make projects based on it more competitive. A few constraints on the establishment of a Charter airline operator based in Port Elizabeth are： the lack of adequate runway for the landing of the long-haul carriers and the need of a larger liberalisation of the aviation policy by eliminating protectionism. The cost benefit analysis undertaken in this research does not take into account social costs and benefits to the economy of establishing a Charter airline based in Port Elizabeth, such as an employment, infrastructure development and poverty alleviation. Nevertheless the analysis does suggest that there are strong private and social benefits warranting the establishment of an airline business between Europe and Port Elizabeth. The economic benefits of the tourism industry and its link to airline travel are outlined in section 3. It is shown that the growth of the airline industry is a major component and contributor to tourism growth.

Replacement of Fish Meal with Graded Levels of Earthworm Meal in the Diet of Fingerlings： Effect on Feed and Growth Parameters

The study was aimed at evaluating growth response of Heteroclarias fingerlings fed diet in which fish meal was substituted with graded levels of earthworm meal. The replacement levels were 0.00%, 25%, 50%, 75% and 100% designated as Eo, E25, Es0, E75 and El00, respectively. Fingerlings used for the work were obtained through artificial insemination of brood stock （purchased from local farmers） with ovaprim in the laboratory. The resulting fry were reared and fed with cultured plankton for 2 weeks followed by 100% fish meal for another two weeks. Thereafter sixteen fingerlings weighing 4.73 g and measuring 6.512 mm standard length （on the average） were starved over night and reared in five indoors tanks （0.8 ~ 0.5 ~ 0.5 m） in duplicate for eight weeks. Fingerlings were fed on graded earthworm meals of 40% protein twice daily at 08：00 and 16：00. The highest mean weight （6.77 g）, specific growth rate （0.86） and protein efficiency ratio （0.6） were obtained at 50% replacement level. Also, Food conversion ratio was the highest at 50% substitution level and lowest at 0.00% substitution, indicating that fingerlings use earthworm containing meal more efficiently. Furthermore, cost benefit analysis revealed that the profit index for 50% inclusion of earthworm meal was the highest （1.71） and the highest net profit of N374.32 （circa $2.3） was achieved at this level. Water quality parameters observed were within tolerable values for the fingerlings well being. Consequently, farmers are advised to use 50% earthworm meal in place of fish meal for formulation of Heteroclarias fingerlings diet. This will drastically reduce production cost, increase farmers profit and enhance the biological value of our menu.

Joining Paths and Dividing Paths： Juiz de Fora, Brazil

The aim of this paper is to present the urban history of Juiz de Fora, a city with some 500,000 inhabitants in southeastern Brazil, and discuss how strategic decisions about the planning and construction of roads and highways can determine ways of life in a city. While paths may integrate landholdings and territories, they may also segregate communities and environments, causing deep rifts in the fabric of urban and land areas. The growth of Juiz de Fora is particularly marked by the construction of paths. This article reviews the local urban history from the establishment of paths in the city, to an analysis of the major impact and benefits they have had, notably on the local economy and demographics, as well as on the conservation of the local environment： Issues that are frequently relegated to a secondary role in the cost-benefit analysis of the city＇s planning decisions. After analysis of the case study, the authors concluded that citizens should be included on the agenda of the city, from spectators to actors of daily urban life.

A New Criteria to Apply Weight-Dependent CATSthr to Cost-Benefit Analysis within the Framework of IMO EnvironmentaI-FSA Studies

The purpose of this paper is to investigate reasonable cost benefit criteria within the framework of environmental formal safety assessment （FSA）. In this study a statistical analysis of oil spill data was carried out based on the report of International Oil Pollution Compensation Funds. According to the statistical study of actual oil spill from tankers, it is found that collisions and groundings are the most probable causes of the oil spills from tankers. Probability distributions of costs of oil spill and oil spill amount are investigated, and a non-linear regression formula between costs of oil spills and oil spill weight are derived. Using the regression formula, an oil spill weight dependent CATStm （Cost of Averting a Ton of oil Spilt） is proposed. Moreover in order to apply the weight dependent CATSthr to cost benefit analysis （CBA）, a new cost-effective criterion is newly proposed with considering its concrete application to environmental FSA.