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1.
This paper presents a genetic algorithm (GA) for parallel redundancy optimization in series-parallel power systems exhibiting multi-state behavior, optimizing the reliability subject to constraints. The components are binary and chosen from a list of products available in the market, and are being characterized by their feeding capacity, reliability, cost and weight. System reliability is defined as the ability to satisfy consumer demand and is presented as a piecewise cumulative load curve. In GA, to handle infeasible solutions penalty strategies are used. Penalty technique keep a certain amount of infeasible solutions in each generation so as to enforce genetic search towards an optimal solution from sides of, both, feasible and infeasible regions. We here present a dynamic adaptive penalty function which helps the algorithm to search efficiently for optimal/near optimal solution. To evaluate system reliability, a fast procedure, based on universal generating function, is used. An example considering a multi-state series-parallel power system is solved considering both homogeneous and heterogeneous types of redundancy. Also an example considering price discounts is solved. The effectiveness of the penalty function and the proposed algorithm is studied and shown graphically.  相似文献   
2.
Natural disasters can lead to significant changes in health, economic, and demographic outcomes. However, the demographic effects of earthquakes have been studied only to a limited degree. This paper examines the effect of the 2001 Gujarat earthquake on reproductive outcomes. This earthquake killed more than 20,000 people; injured 167,000; and caused massive losses to property and civic assets. Using data from two large-scale District-Level Household Surveys (2002–2004 and 2007–2008), we employ difference-in-difference and fixed-effect regression models to compare the outcomes across earthquake-affected districts and their neighboring districts during 5 years before and after the earthquake. We find that the earthquake led to significant rises in childbirth rates. It also reduced birth spacing among uneducated, tribal, and Muslim women, and the incidence of male births among rural women. We find considerable variation in the demographic effects of the earthquake across location, household socioeconomic status, and parental age and education.  相似文献   
3.
In this paper, we empirically assess the role of individual social capital on personal bankruptcy and default outcomes in the consumer credit market. After controlling for a borrower’s risk score, debt, income, wealth, and legal and economic environments, we find that default/bankruptcy risk rises and then falls over the lifecycle, while a borrower who owns a home or is married has a lower risk of default/bankruptcy. Moreover, a borrower who migrates 190 miles from his “state of birth” is 17% more likely to default and 15% more likely to file for bankruptcy, while a borrower who continues to live in his state of birth is 14% and 10% less likely to default and file for bankruptcy, respectively. A borrower who moves to a rural area is 9% and 7% less likely to default and declare bankruptcy, respectively. We also find that measures of social networks, norms, and cooperation and trust (i.e., aggregate social capital) are inversely related to consumer bankruptcy.  相似文献   
4.
Incentive‐based approaches have gained policy interest in linking change in agricultural land management with environmental conservation. This article investigates how scheme design influences smallholder farmers' decisions to switch to organic farming to reduce water pollution, drawing on a study at a Ramsar wetland site providing water for the city of Bhopal. Results from a choice experiment suggest that transitional payments are necessary to overcome farmer constraints to adopt organic farming, and that effective land certification has the potential to act as a self‐enforcing mechanism linking farmer incomes with wetland conservation benefits.  相似文献   
5.
In the present paper, the author has considered and compared the power of three test procedures, based on two preliminary tests of significance (PTS), for testing a main effect in a three factor factorial experiment. Davenport and Webster (1973) type test statistics are used in the final test. Recommendation for a suitable size of PTS has been made so that the power of a test procedure is adequately high.  相似文献   
6.
The often paradoxical relationship between investment in information technology and gains in productivity has recently been attributed to a lack of user acceptance of information technology innovations. Diverse streams of research have attempted to explain and predict user acceptance of new information technologies. A common theme underlying these various research streams is the inclusion of the perceived characteristics of an innovation as key independent variables. Furthermore, prior research has utilized different outcomes to represent user acceptance behavior. In this paper we focus on individual's perceptions about the characteristics of the target technology as explanatory and predictive variables for acceptance behavior, and present an empirical study examining the effects of these perceptions on two frequently used outcomes in the context of the innovation represented by the World Wide Web. The two outcomes examined are initial use of an innovation and intentions to continue such use in the future, that is, to routinize technology use. Two research questions motivated and guided the study. First, are the perceptions that predict initial use the same as those that predict future use intentions? Our results confirm, as hypothesized by prior research, that innovation characteristics do explain acceptance behavior. The results further reveal that the specific characteristics that are relevant for each acceptance outcome are different. The second research question asks if perceived voluntariness plays a role in technology acceptance. Results show that external pressure has an impact on adopters' acceptance behavior. Theoretical and practical implications that follow are presented.  相似文献   
7.
Understanding institutional systems is critical for the advancement of women's participation in leadership in varying contexts. A unique and global analysis of the contextual factors that affect women in political leadership, this paper extends prior research in the field. This is a cross-country study where we ask, “How are societal-level institutional forces related to women's participation in political leadership?” We collected data from 8 secondary sources on 181 countries and conducted linear regression analyses with six institutional influences: the business environment, societal development, the economic environment, physical and technological infrastructure, political freedom, and culture. Results indicate that to increase the political leadership participation of women, we need to evaluate the following: customs and trade regulations, graft, the gender gap in political empowerment, public spending on education, the economic viability of the country, access to power and the internet, political freedom, and cultural variables like performance orientation, collectivism, and power distance.  相似文献   
8.
The authors discuss a number of variables that may influence the perception of ethical climate in the nonprofit sector, including individual, organizational, and significant other (peers, coworkers, and superiors) variables. The basis of this discussion is the model developed by Agarwal and Malloy (1999) identifying a framework for nonprofits that is distinct from the for‐profit orientation. The authors provide ten propositions and discuss their implications.  相似文献   
9.
The problem of estimating the population totals of multiple characteristics using without replacement sampling design is addressed. The alternative estimators for the study characteristics which are unrelated or have the low correlations with the characteristic used in sample selection are suggested. The efficiency of the estimators under two super population models, approximating the situations in which both the characteristics are unrelated and also when they are related, is studed. A numerical investigation is also carried out to get insight into the performance of the estimators in real applications.  相似文献   
10.
Measuring the determinants of relative economic performance of rural areas   总被引:1,自引:0,他引:1  
This paper examines the determinants of economic performance of 149 English rural Local Authority Districts (LADs). A Three Stage Least Square (3SLS) estimation procedure was employed to jointly determine the influence of a wide range of indicators representing economic, human, cultural and environmental capital, as well as less tangible or ‘soft’ factors on three distinct components of economic performance: productivity, employment and labor market participation. The results reveal that a range of facets of economic and human capital, including the three key drivers of productivity (skills, investment and enterprise), spatial factors (peripherality and accessibility), and other key factors (economic structure, government infrastructure, road infrastructure, and occupational health), are significant determinants of economic performance in rural areas. This study is of value since it proposes a method for modelling the determinants of economic performance which is transferable to other environments in the UK and beyond. In addition, it proposes a set of benchmarks of economic performance using readily available data, and highlights some implications for rural policy and several avenues for future research.  相似文献   
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