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81.
Lucy Lee Maria Marti Villalba Robert B. Smith James Davis 《Electrochemistry communications》2009,11(8):1555-1558
The use of a novel epoxide label system as the basis of a new approach to monitoring thiol species relevant to animal welfare contexts is presented. The need for the development of on-site/field testing is demonstrated through the analysis of equine saliva before and after exercise and the implication of delays in the analysis process exposed. The system is selective for thiols and, in contrast to simpler labelling systems, could offer potential for speciation studies. 相似文献
82.
David J. Mayston 《Mathematical Social Sciences》1982,3(2):109-129
Against the background of recent impossibility theorems, the paper establishes a number of rules for the formation of social preferences to ensure the generation of a Bergson-Samuelson social welfare function of the desired ‘individualistic’ form. It demonstrates that such welfare functions can indeed exist under conditions of simply ordinality of individual preferences and a lack of interpersonal comparability, for the general n-person case with only weak restrictions upon individual preferences. A valuable tool of social welfare theory for the single-profile case is therefore restored under a wide set of conditions. By examining Kemp and Ng's justification for their A3 condition in this context, we are able also to highlight a number of key differences between the conditions satisfied by many political constitutions and the requirements for achieving the positive existence of a Bergson-Samuelson social welfare function. In particular the paper focusses here on the weighting systems on individual preferences that are consistent with generating an individualistic welfare function and examines the information content of individual ordinal preferences which must be utilized if the desired welfare function is to result. 相似文献
83.
本文以中国民航产业为例,运用227条国内主要客运航线市场的横截面数据,通过回归分析估计了中国民航国内市场的反需求函数。在此基础上,估算了中国民航市场竞争对消费者福利的影响。最后,文章分析比较了目前客运量最大的20条国内航线的消费者福利。 相似文献
84.
We prove Arrow's theorem for tree quasi-orders and discuss it in the context of attempting to construct the evolutionary history of a group of species. We then characterize axiomatically two natural classes of consensus rules for classifications. 相似文献
85.
86.
The paper is devoted to applications of modern tools of variational analysis to equilibrium models of welfare economics involving
generally nonconvex economies with infinite-dimensional commodity spaces. The main results relate to the so-called generalized/extended second welfare theorem ensuring an equilibrium price support at Pareto optimal allocations. Based on advanced tools of variational analysis and
generalized differentiation, we establish refined results of this type with the novel usage of nonlinear prices at the three types to optimal allocations: weak Pareto, Pareto, and strong Pareto. We pay a special attention to strong Pareto optimal allocations in economies with ordering commodity spaces showing that enhanced results for them do not require, in contrast to the classical types of weak Pareto and Pareto optimality, any net demand qualification conditions.
Mathematics Subject Classifications (2000): 91B50, 49J52
Dedicated to the memory of Yuri Abramovich 相似文献
87.
While the developments of additive manufacturing (AM) techniques have been remarkable thus far, they are still significantly limited by the range of printable, functional material systems that meet the requirements of a broad range of industries; including the health care, manufacturing, packaging, aerospace, and automotive industries. Furthermore, with the rising demand for sustainable developments, this review broadly gives the reader a good overview of existing AM techniques; with more focus on the extrusion-based technologies (fused deposition modeling and direct ink writing) due to their scalability, cost efficiency and wider range of material processability. It then goes on to identify the innovative materials and recent research activities that may support the sustainable development of extrusion-based techniques for functional and multifunctional (4D printing) part and product fabrication. 相似文献
88.
按是否拥有传统汽车将潜在消费者分成两类,基于不同购买行为的消费者,根据消费者购买行为理论,针对每一类消费者分别建立效用模型,运用斯坦伯格博弈理论求解得到厂商的最优定价策略和政府的最优补贴策略,进而分析政府考虑包括厂商收益、消费者剩余、政府支出以及环境效益在内的社会福利最大化时电动汽车的环境质量、传统汽车原拥有比例以及消费者惯性三因素对电动汽车普及率、政府补贴以及生产商收益的影响。研究结果表明:当生产成本小于某阀值时,电动汽车的市场需求随电动汽车的环境质量的增加而增大,传统汽车的市场需求则随之减小,反之亦然。电动汽车的生产效率较高时,政府的最优补贴随产品环境质量的增加而增大,生产效率较低时,最优补贴随之减小,政府通过增大补贴的方式鼓励生产商提高生产效率。最后通过数值实验验证了以上结论,并分析得到以上三方面因素对生产商收益的影响。 相似文献
89.
“氢、氮、氧、氟、氯”是现代化学中十分重要的元素,但是这些名词的创制与传播过程一直不太明晰。本文研究发现,“氢、氟、氯”1908年由中国化学会欧洲支会首创,其成果被1909年设立的编订名词馆吸收,并创制了“氮、氧”。这些译名在创制之初未能产生重要影响,1920年后才在郑贞文与商务印书馆的大力支持下被广泛使用,并最终在1932年的教育部化学讨论会上被确定下来,为化学界所接受。 相似文献
90.