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261.
This paper introduces a new approach for conducting project feasibility study by embracing the principles of sustainable development. Construction projects, in particular, infrastructures have major influence on the attainment of sustainable development, thus project sustainability needs to be considered. This becomes a pressing issue particularly in those developing countries or regions, such as China where a huge amount of construction works are currently performed and remain to happen in the future. Previous study has addressed little on the relevance of project feasibility study to project sustainability performance. The importance of incorporating sustainable development principles in conducting project feasibility study is not effectively understood by project stakeholders. This paper addresses major challenges of undertaking project feasibility study in line with sustainable construction practice with reference to the Chinese construction industry. A case study approach is the major research method in this study. The research team collected 87 feasibility study reports from various projects. Attributes are used for measuring project performance, including 18 economic performance attributes, nine social performance attributes, and eight environmental performance attributes. Research results show that economic performance is given the most concern in the current practice of project feasibility study, whilst less attention is given to the social and environmental performance. The study reveals the insufficiency of examining the performance of implementing a construction project from the perspective of sustainable development. The results also suggest the need for shifting the traditional approach of project feasibility study to a new approach that embraces the principles of sustainable development.  相似文献   
262.
Extensive research has examined the relationship between environmental management/performance and business performance but yielded no conclusive results. This paper makes two contributions to the literature. First, instead of focusing on one aspect, we try to compare using various types of cleaner production activities: low- and high-cost activities. Second, the study complements the existing literature which focuses on firms in developed countries with an analysis of firms in the Chinese manufacturing industry. In this paper, the relationship between cleaner production and business performance was analyzed using Structure Equation Model (SEM). We find an overall positive impact of cleaner production on firm's business performance. We also found that the cleaner production activities of low-cost scheme have a bigger contribution to financial performance compared to non-financial performance, while cleaner production activities of high-cost scheme have a greater contribution to non-financial performance, compared to financial performance. This study should be useful for firms that consider adopting cleaner production as well as stakeholders who aim to promote cleaner production.  相似文献   
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Heterospecific matings are generally assumed to be unconditionally disadvantageous due to reduced viability or fertility of hybrid offspring. For female collared flycatchers (Ficedula albicollis) mated to male pied flycatchers (Ficedula hypoleuca), the cost of heterospecific pair formation is reduced due to high levels of conspecific extra-pair paternity and a male-biased offspring sex ratio. In order to investigate whether these cost-reducing mechanisms are the result of female mating strategies, rather than being a by-product of species incompatibilities, we manipulated the plumage of male collared flycatchers before pair formation to make them resemble male pied flycatchers. Since species incompatibilities are absent in this design, any systematic effect of manipulation on sex ratio or paternity would indicate a role of female mating strategy. Paternity was determined by means of a likelihood approach that controls the errors made in assigning a chick to be ‘within-pair’ or ‘extra-pair’. Neither the sex ratio nor the male share of paternity was affected by the manipulation in a systematic manner. We therefore conclude that our experimental data provide no support for the suggestion that female behavioural strategies are markedly adjusted in response to formation of mixed-species pairs. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users.  相似文献   
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This paper describes the isolation of monoclonal antibodies and the development of competitive immunoassays to pesticide metabolites of the fungicides imazalil, carbendazim and thiabendazole. The metabolite specific hydroxyl residues were used as the reactive group with which to link the metabolite to the carrier proteins Keyhole Limpet Haemocyanin (KLH) and Bovine Serum Albumin (BSA). In each case immune responses in mice were raised and monoclonal antibodies were produced. Antibodies were developed into competitive ELISAs to the appropriate metabolite. The antibody raised to a metabolite of imazalil was optimised into a competitive ELISA format which had an assay IC50 of 7.5 μg/L and a limit of detection (LOD) of 1.1 μg/L. A single antibody isolated against the metabolite of carbendazim had assay IC50s of 3.2 and 2.7 μg/L for the metabolites of carbendazim and thiabendazole respectively with an LOD of 0.38 μg/L for both. These sensitive immunoassays may have application in the monitoring of human exposure to these fungicide residues either by occupational or non-occupational routes.  相似文献   
267.
中国长江三角洲地区电力行业SO2排放控制的经济分析   总被引:13,自引:5,他引:8  
总结了中国SO2排放总量控制与排放权交易政策研究与实施3个阶段的主要内容与成果。使用YRDEGS线性规划优化模型对在长江三角洲地区电力行业实施SO2排放权交易所能产生的SO2控制费用的节省、安装FGD装机容量的变化、可引起的脱硫变动成本的节约、SO2排放许可的市场需求、不同交易方式所引起的脱硫费用变化进行分析,得到以下主要结论:若发电量保持在2000年的水平,实现SO2减排20%的目标,采用排污交易脱硫费用将会节省38%,可以少安装FGD的机组装机容量达6.3GW;随着发电量的增加,对SO2排放许可指标的市场需求呈增长趋势,发电量的改变比逐步严格的SO2减排要求更会增加区域SO2减排的负担;当SO2排放削减率为20%时,在不实施排污交易时脱硫费用约为30亿~45亿元;实施跨省排污交易以电厂为交易单位时费用最低,约为6亿~28.5亿元,脱硫费用可以节省16.5亿~24亿元。  相似文献   
268.
Understanding of hunter preferences for hunting lease attributes is important to landowners because such knowledge provides key information for managing and marketing fee-hunting in order to maximize revenues. Premised on this insight, we used attribute based modeling to investigate how hunter preferences for potential leases were influenced by lease and hunter-specific attributes. A mail survey of Mississippi licensed hunters provided the necessary data. Estimation results based on McFadden conditional logit regression suggested that lease attributes including game diversity, lease location relative to hunter residence, lease size, lease duration and lease rate influenced willingness to pay for additional units of lease attributes. Depending on the specific levels of these attributes, WTP could vary as much as $5.70 per acre. Of the hunter-specific attributes, age and income significantly influenced hunter decision to buy a lease or opt for status quo. Results of this study should assist landowners in increasing financial returns from fee-hunting endeavors through appropriate changes to their hunting access policies and wildlife management activities in response to hunter preferences regarding lease attributes.  相似文献   
269.
Public and private organizations need a robust approach to prepare, respond, and recover from cyber-attacks. This perspective article will refer to such an approach as Cyber First AID—adaptable, integrated, and deliberate. Adaptable describes that one size does not fit all; Integrated means the effort is throughout the organization; and Deliberate describes plans that are reviewed periodically and practiced, in which all members of the organization know their respective roles and responsibilities. The article outlines a decision-making process for how to minimize the impacts of cyber threats, maintain stakeholder and customer confidence, and help organizations to adaptively manage and respond to cyber threats in rapidly changing cyber environments.  相似文献   
270.
为减少烯烃类爆炸事故带来的严重危害,采用国际通用的20L球型爆炸测试装置测试了常温初始压力为0.1 MPa条件下,4种常见烯烃的爆炸特性参数.结果表明,随着烯烃含量的增加各项爆炸特性参数均呈现出先增大后减小的特征,最大爆炸压力和爆炸指数均在化学计量比附近获得,4种烯烃最大爆炸压力分别为乙烯1.5 MPa、丙烯1.3 MPa、正丁烯1.5 MPa、异丁烯1.6 MPa,爆炸指数分别为16.56 (MPa·m)/s、7.37(MPa·m)/s、16.98 (MPa·m)/s、29.07(MPa· m)/s.  相似文献   
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