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91.
The objective of the paper is to estimate environmental externalities related to a run of river project in Sri Lanka and to investigate inequity in distribution of impacts among different social groups. Diversion of the river resulted in loss of water sports (for high-income groups both local and remote), loss of historical monuments (for remote high-income groups) and recreation losses (for local poor). Removal of forest cover leads to loss of non-timber products (for local poor) and carbon storage (for remote high- and low-income groups). Loss of home garden productivity was borne by local poor groups. Benefit of the project, generation of 145 GWh annually, was a gain for the grid connected groups. The impacts were valued using various valuation methods. The base case of the cost benefit analysis resulted in NPV of US$ 11,335,730. When distributional weights are applied for different income groups, both the sign and magnitude of net benefits change. In order to be viable, the project needs diversion of at least 9% of generated electricity to the poorest households in the country. Implications for energy policy towards reducing externality and inequality impacts are also discussed.  相似文献   
92.
A multi-agent system for energy management of distributed power sources   总被引:1,自引:0,他引:1  
The field of energy management is an area increasingly studied. However, most solutions are based on centralized systems and barely fulfil criterion like fault tolerance or adaptability. Also, these systems are often difficult to design because of the “top–down” approach used: the designer generally knows how each component has to respond separately, but a centralized management system focuses his attention solely on the overall reaction of the system. That is why a distributed management solution based on the paradigm of Multi-Agent Systems (MASs) is proposed in this paper. In addition to a more natural conception, based on a “bottom–up” approach, this solution ensures better system reliability. After reviewing the previous works, an application of MAS to power management in a hybrid power source is presented. Then, the system is tested using a simulation model. The results show that this approach is perfectly valid and can respond to most problems of centralized energy management systems (EMSs).  相似文献   
93.
Abstract

The Water Poverty Index is an integrated tool developed on the basis of extensive consultation with a range of scientists, practitioners and policymakers. It is primarily designed for use at the community level to enable more holistic water-resource assessments on a site-specific basis. It can however be applied at different scales to suit different needs. One of the motivations to design such a tool was an attempt to move away from the conventional, purely deterministic, approaches to water assessment, relying primarily on models and large-scale data. In today's world such an approach is inappropriate, ill representing the complexities of modern water-allocation decisions where economic, political and social issues all have a powerful role to play. This paper highlights some applications of the Water Poverty Index at different spatial scales and discusses the implications of applying indicators at these different scales.  相似文献   
94.
Collaborative Information Seeking   总被引:1,自引:0,他引:1  
An examination of the roles and dimensions of collaborative search reveals new opportunities for information-seeking support tools.  相似文献   
95.
96.
Presents an interview that was conducted by Jeremy Safran with Lewis Aron on the topic of psychoanalysis. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
97.
正从国民初恋到学霸少年,从天才侦探到高冷音乐人,少年成名,十几岁的他收获了万千宠爱。荧幕上,他青春无敌,穿梭在不同角色之间,彷佛有他的地方就满是青春荷尔蒙气息,极具个人特征的虎牙和笑脸,都是我们最爱的少年气。逆天资源背后的开挂推手1997年,刘昊然出生在河南省的一个普通家庭,11岁那年考上了北京舞蹈学院附中,于是刚刚小学毕业的他就开启了北漂的求学生活。  相似文献   
98.
Companies must ensure their software complies with relevant laws and regulations to avoid the risk of costly penalties, lost reputation, and brand damage resulting from non-compliance. Laws and regulations contain internal cross-references to portions of the same legal text, as well as cross-references to external legal texts. These cross-references introduce ambiguities, exceptions, as well as other challenges to regulatory compliance. Requirements engineers need guidance as to how to address cross-references in order to comply with the requirements of the law. Herein, we analyze each external cross-reference within the U.S. Health Insurance Portability and Accountability Act (HIPAA) Privacy Rule, the Gramm?CLeach?CBliley Act (GLBA), and the GLBA Financial Privacy Rule to determine whether a cross-reference either introduces a conflicting requirement, a conflicting definition, or refines an existing requirement. Herein, we propose a legal cross-reference taxonomy to aid requirements engineers in classifying cross-references as they specify compliance requirements. Analyzing cross-references enables us to address conflicting requirements that may otherwise thwart legal compliance. We identify five sets of conflicting compliance requirements and recommend strategies for resolving these conflicts.  相似文献   
99.
Serine hydrolases have diverse intracellular substrates, biological functions, and structural plasticity, and are thus important for biocatalyst design. Amongst serine hydrolases, the recently described ybfF enzyme family are promising novel biocatalysts with an unusual bifurcated substrate‐binding cleft and the ability to recognize commercially relevant substrates. We characterized in detail the substrate selectivity of a novel ybfF enzyme from Vibrio cholerae (Vc‐ybfF) by using a 21‐member library of fluorogenic ester substrates. We assigned the roles of the two substrate‐binding clefts in controlling the substrate selectivity and folded stability of Vc‐ybfF by comprehensive substitution analysis. The overall substrate preference of Vc‐ybfF was for short polar chains, but it retained significant activity with a range of cyclic and extended esters. This broad substrate specificity combined with the substitutional analysis demonstrates that the larger binding cleft controls the substrate specificity of Vc‐ybfF. Key selectivity residues (Tyr116, Arg120, Tyr209) are also located at the larger binding pocket and control the substrate specificity profile. In the structure of ybfF the narrower binding cleft contains water molecules prepositioned for hydrolysis, but based on substitution this cleft showed only minimal contribution to catalysis. Instead, the residues surrounding the narrow binding cleft and at the entrance to the binding pocket contributed significantly to the folded stability of Vc‐ybfF. The relative contributions of each cleft of the binding pocket to the catalytic activity and folded stability of Vc‐ybfF provide a valuable map for designing future biocatalysts based on the ybfF scaffold.  相似文献   
100.
In recent years, laser and electron beam welding techniques have been developed with heating rates reaching 1 million K/s, and nonequilibrium microstructures sometimes result. In the present study, the alpha (bcc) to gamma (fcc) transformation in pure iron is studied using a bank of storage batteries for heating and a high speed data acquisition system to monitor the temperature determined from a thermocouple spot welded to the specimen. Heating rates up to 300,000 K/s were obtained with the transformation temperature increasing from the equilibrium value of 1185 K (912 °C) to over 2200 K (1927 °C). The results are presented in terms of continuous heating and isothermal transformation curves.  相似文献   
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