一种无奇异参数椭圆柱形电磁隐身斗篷的设计基础理论

目的研究无奇异参数的椭圆柱形超材料电磁隐身斗篷的设计方法。方法应用变换光学原理建立空间变换坐标表达式,推导出该斗篷的电磁参数张量,再采用Matlab软件验证所推导张量的无奇异性,最后采用有限元仿真软件验证该斗篷的电磁隐身性能。结果椭圆柱形斗篷具备良好的电磁隐身性能,并且其电磁参数张量的各个分量均无奇异性。结论设计出的空间坐标变换方式能够从理论上实现无奇异参数的超材料电磁隐身斗篷,这种方法也拓展了变换光学原理在超材料隐身装置设计方面的应用。     

Invisible Losses and the Logics of Resettlement Compensation

The necessity of compensating people negatively affected by conservation and other development projects has been widely acknowledged. It is less widely acknowledged that because conventional compensation assessments focus on material resources and their economic equivalents, many important losses incurred by resettlers are invisible to project authorities. Through ethnographic observations and interviews, we documented losses identified by people facing resettlement from Mozambique's Limpopo National Park. We also examined resettlement planning documents to determine why decision makers’ assessments of natural resource use and value neglect losses residents identified as critical. Identifying, preventing, and mitigating invisible losses in resettlement planning necessitates a better understanding of intangible benefits residents derive from resources, which are often as or more important than their readily apparent material properties. These benefits include but are not limited to decision‐making authority linked to owning land versus having the use of fields; ancestral identity and social belonging linked to gravesites; the importance of tree roots that provide a powerful sense of security because they suppress hunger in periods of scarcity; and the importance of people's location within social networks and hierarchies as they determine the benefits versus risks that will be incurred through resettlement. Pérdidas Invisibles y la Lógica de la Compensación de Repoblación     

关于无烟柴油机的探讨

从技术上探讨了如何最大程序地降低排放物的污染,从而实施“无烟”的柴油机;定量地分析了柴油机各类排放物及其控制技术的效果。只要最优化组合并进一步改进这些技术,无烟柴油机的目标就可以实现。这也将是今后船用柴油机研制和生产的方向。     

PROFITS,JOINT COSTS AND WATER QUALITY CONTROL1

ABSTRACT. Federal guidelines for the establishment of water quality standards prohibit degradation of the properties of all or part of the nation's aquatic resources. It is probably correct that streams, lakes and aquifers should be free of toxic substances while non-poisonous deposits should be abated. However, an extreme opposing position is held by some proponents of pollution who intend to continue discharging waste materials until forced to stop. Although it would seem otherwise, the underlying problem is that polluters' points of altercation possess merit in particular instances. Accordingly, efficient abatement will require that appropriate laws be formulated in such a manner that the nature of economic reasons for the disposal of waste materials be disclosed. Moreover, the technological ability to create byproducts from these particular elements or compounds can advance only over time. This, coupled with the fact that scientists have not developed inexpensive treatment methods which are totally effective, justifies more flexible formal regulations. Excessive rigidity of standards could impose a burden on polluters that is greater than the cost to society which the damaging firm or individual is generating. On the other hand, uniform rules in some cases could be considered so lenient as to allow flagrant contamination which unduly injures downstream users.     

中国原油的地球化学特征——兼论中国原油的有机与无机来源

中国大庆、辽河、大港、新疆等油区原油的地球化学组成显示以下特征 :含有地壳稀少而地球深部丰富的元素 ,如Re、In、Cd、Ag、Au等 ;含有生物质平均成分不见的元素 ,如Be、Ga、Zr、Nb、Sb、Te、Hf、Ta、W、Tl、Bi、Th等 ;含有较多的亲石元素 ,如Ca、Mg、K、Na、V、Li、Be、B、Ti、Cr、Mn、Rb、Sr、Y、Zr、Nb、Cs、Ba、Hf、Ta、W、Th、U等 ;原油的正烷烃结构具有奇偶优势与不显奇偶优势的特征 ,不显奇偶优势的原油沿基底断裂分布。地球化学特征是矿产资源形成途径的示踪标志。中国原油中含有生物质中不见的元素 ,说明原油可能有来自非生物成因的油源 ;含有地壳稀少而地球深部丰富的元素 ,说明原油可能有来自地球深部成因的油源 ;含有较多的亲石元素 ,说明原油可能不是从生油岩中排出的 ,而是从非岩石结构的地球深部流体中分异后聚集在岩石结构的孔隙中而形成油层的。原油的正烷烃结构显示的奇偶优势被认为系生物成因的油源 ,而不显奇偶优势被认为是甲烷石油 (即来自地球深部的无机成因油源 ) ,不显奇偶优势的油样均沿基底断裂分布 ,正旁证了地球深部来源的可能性。     

灾害无形损害的评价研究——心理损害与伦理创伤产生的原因与抚慰

随着人类社会的发展,灾害对社会破坏程度的评价标准逐渐提高,从单纯的物质损害上升到对人们精神损害的评价.心理损害与伦理创伤是灾后社会要面对的一个重大问题,究其产生的原因及如何合理处置是我们制度评价体系要研究的重要课题.