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61.
62.
One of the most important aspects of the (statistical) analysis of imprecise data is the usage of a suitable distance on the family of all compact, convex fuzzy sets, which is not too hard to calculate and which reflects the intuitive meaning of fuzzy sets. On the basis of expressing the metric of Bertoluzza et al. [C. Bertoluzza, N. Corral, A. Salas, On a new class of distances between fuzzy numbers, Mathware Soft Comput. 2 (1995) 71-84] in terms of the mid points and spreads of the corresponding intervals we construct new families of metrics on the family of all d-dimensional compact convex sets as well as on the family of all d-dimensional compact convex fuzzy sets. It is shown that these metrics not only fulfill many good properties, but also that they are easy to calculate and easy to manage for statistical purposes, and therefore, useful from the practical point of view. 相似文献
63.
Paul G. Lewis Mark Baldassare 《Journal of the American Planning Association. American Planning Association》2013,79(2):219-237
Problem: The future of compact development depends in part on understanding and shaping the public's attitudes toward it. Previous studies have suggested life cycle, socioeconomic, attitudinal, and ideological dimensions to preferences regarding development patterns, but rarely have all of these factors been examined systematically across a broad, generalizable sample of respondents. Purpose: To examine public attitudes toward compact development, we asked survey respondents to weigh four important tradeoffs between compact and sprawling growth. We assess the relative influence of a variety of individual characteristics on these attitudes. Methods: We use results from two large-scale, randomized telephone surveys, one conducted in California in 2002 and the other in four other southwestern states in 2007. Using logistic regression, we assess which personal characteristics are associated with stated preferences regarding compact development, and illustrate their degree of influence. Results and conclusions: Support for the compact development alternatives is significant, in some cases exceeding support for traditional, decentralized suburban patterns. However, question wording appears to matter considerably, and individuals’ beliefs about different facets of compact development are often inconsistent. Although race, income, age, and the presence of children in the household are strongly associated with some views on the four tradeoffs, only political ideology is consistently associated with opposition to compact development. Takeaway for practice: The significant support evident for compact development may not translate into actual housing choices unless local governments and lenders do more to support the production of such housing and neighborhood environments. If, as our results suggest, a major constituency for transit-oriented and mixed-use projects is low income residents, renters, and minorities, then well crafted urban infill projects that take into account the needs of these groups will help fulfill the potential of smart growth. Advocates might also frame compact development to appeal more to political conservatives. Research support: The 2002 survey was conducted by the Public Policy Institute of California, with financial support from the William and Flora Hewlett Foundation, James Irvine Foundation, and David and Lucille Packard Foundation. The 2007 survey was conducted and supported by the Institute for Social Science Research at Arizona State University. All views expressed are solely those of the authors, not these organizations. 相似文献
64.
65.
《Journal of Nuclear Science and Technology》2013,50(3):325-333
The mechanisms of coating failure of the fuel particles for the high-temperature gas-cooled reactors during coating and compaction processes of the fuel fabrication were studied to determine a way to reduce the defective particle fraction of the as-manufactured fuels. Through the observation of the defective particles, it was found that the coating failure during the coating process was mainly caused by the strong mechanical shocks to the particles given by violent particle fluidization in the coater and by unloading and loading of the particles. The coating failure during the compaction process was probably related to the direct contact with neighboring particles in the fuel compacts. The coating process was improved by optimizing the mode of the particle fluidization and by developing the process without unloading and loading of the particles at intermediate coating process. The compaction process was improved by optimizing the combination of the pressing temperature and the pressing speed of the overcoated particles. Through these modifications of the fabrication process, the quality of the as-manufactured fuel compacts was improved outstandingly. 相似文献
66.
Arne Sloth Jensen 《Drying Technology》2013,31(5-7):1377-1393
ABSTRACT Drying in superheated steam under pressure gives possibilities for pollution free drying, energy recovery. reduced drying time and a very compact drying equipment. Products are dried i n a pressurized cellular fluid bed by super heated steam blown through the cells. Above the fluid bed dust is separated before the steam is reheated and recirculated to the cells by a fan. The evaporated water leaves the dryer as usable steam at e.g. 3 bar g, and full energy recovery is obtained. Today 14 plants have been builtor are under construction, with capacities from 2 to 40t / h water evaporation. This technology is suited for drying of beet pulp, residues from starch production of corn or wheat. sludge. spent grain. brown coal. wood chips and bark. The technology shows great options for integration in steam systems in various industries, whereby drying is possible without using primary energy and pollution is avoided. 相似文献
67.
《分离科学与技术》2012,47(2):247-259
Abstract Compact arrangement of the disk type PSA columns results in considerable reduction of the equipment size and the effect of adsorption heat on process performance. More effort has been made presently to improve the performance of the new design in producing oxygen. Considerable improvement is observed due to the replacement of adsorbent ZMS‐5A with ZMS‐VP800 and the adjustment of the operation plan. The feasibility of the compact arrangement of adsorption columns for a PSA process is further proven. 相似文献
68.
We demonstrate a simple and compact optical interferometric unit combined with a conventional optical tweezer system for simultaneous multiple trapping and micromanipulation of mono-dispersed polystyrene spheres and aggregation of small-floating clusters of single-walled carbon nanotubes (SWCNTs). The interferometric unit was made compact by means of coating a thin layer of aluminum oxide on one side of the cubic beam splitter (CBS) which works as a static reference mirror and an adjustable mirror was mounted on a XYZ translational stage facing the other adjacent side of the CBS. Thus, the developed interferometric unit is quite analogous to a Michelson interferometer but is compact. Sinusoidal interference fringes with variable carrier frequency and orientations were generated. The interference fringes were then used for multiple trapping of polystyrene spheres along bright fringes resulting in pattern formation and also the aggregation of tiny floating clusters of SWCNTs. The proposed system is compact and easy to align because of its common-path geometry. 相似文献
69.
结合某乙类厂房的给排水设计,对同类型厂房的自动喷水-泡沫联用系统、淋浴和洗脸盆热水系统、循环冷却水系统的设计要点进行了比较、分析、总结,并提出可供其他项目参考的较为合理的设计方案。 相似文献
70.
哈图岩体侵位于西准噶尔南部早—中泥盆世海相火山-沉积地层中,主要岩性为二长花岗岩、正长花岗岩及少量碱长花岗岩,是研究西准噶尔晚石炭世构造环境的理想对象。哈图岩体花岗岩中SiO2含量(质量分数,下同)为72.06%~76.53%,全碱(Na2O+K2O)为7.80%~8.57%,CaO为0.20%~1.58%,MgO为0.07%~0.42%,明显具有高Si、富碱、贫Ca、低Mg的特征; 这些花岗岩的Al2O3含量为12.55%~14.06%,A/CNK值为1.06~1.15,A/NK值为1.15~1.36,显示其为弱过铝质—强过铝质花岗岩。此外,哈图岩体具有较低的稀土元素总含量((88.14~139.53)×10-6)和高的轻、重稀土元素比值((La/Yb)N值为3.04~6.50),在球粒陨石标准化稀土元素配分模式中显示为典型的右倾“V”字形且具有强烈的负Eu异常,表明源区可能有斜长石残留或出现斜长石的分离结晶作用; 在原始地幔标准化微量元素蛛网图中,这些花岗岩明显富集Rb、Th、U、K、Pb等大离子亲石元素,相对富集Zr、Hf,强烈亏损Sr、Ti、P,相对亏损Ba、Nb。以上特征及主量、微量元素特征和图解表明,哈图岩体为典型的弱过铝质—强过铝质A2型花岗岩,其形成于造山后伸展阶段,是由洋壳和岛弧组成的新生地壳受上涌的幔源物质加热,在浅部低压条件下发生部分熔融,再经分离结晶作用的产物。 相似文献