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11.
I. A. Chaban 《Journal of Superconductivity》1996,9(1):33-42
The impurity mechanism proposed earlier is used to interpret the magnetic properties of hightemperature superconductors. The appearance of superconductive granules and the existence of weak bonds in grains of ceramics and in single crystals is explained. The irreversibility line is obtained and its new interpretation as the line of thresholds of appearance of infinite nonsuperconductive cluster is given. The relaxation time of the magnetic susceptibility in alternating magnetic fields is calculated. The decrease of the Meissner fraction with increase in magnetic field and decrease in doping, and other magnetic properties are explained. 相似文献
12.
13.
Simultaneous solving of balancing and sequencing problems with station-dependent assembly times for mixed-model assembly lines 总被引:1,自引:0,他引:1
In spite of many studies, investigating balancing and sequencing problems in Mixed-Model Assembly Line (MMAL) individually, this paper solves them simultaneously aiming to minimize total utility work. A new Mixed-Integer Linear Programming (MILP) model is developed to provide the exact solution of the problem with station-dependent assembly times. Because of NP-hardness, a Simulated Annealing (SA) is applied and compared to the Co-evolutionary Genetic Algorithm (Co-GA) from the literature. To strengthen the search process, two main hypotheses, namely simultaneous search and feasible search, are developed contrasting Co-GA. Various parameters of SA are reviewed to calibrate the algorithm by means of Taguchi design of experiments. Numerical results statistically show the efficiency and effectiveness of the proposed SA in terms of both the quality of solution and the time of achieving the best solution. Finally, the contribution of each hypothesis in this superiority is analyzed. 相似文献
14.
15.
在机械设计中,圆柱体相贯线上的圆角表示方法是CAD和计算机辅助设计中的难题,所有的CAD/CAM软件都没有这一功能,多数使用者采用的是各种近似方法。本文介绍了严密精确的设计和几何造型方法,可用于大型铸锻件和重型机械的CAD和计算机辅助设计。 相似文献
16.
Three-dimensionally ordered long-range macroporous carbon structures were prepared using commercially available phenolic resin
by utilizing sacrificial colloidal silica crystalline arrays as templates that were subsequently removed by HF etching after
pyrolysis in an argon atmosphere. SEM, TEM, and BET were employed to characterize the morphology and the surface area of the
porous carbon structures. The pore size (150–1000 nm) and BET surface area, which reflect pore volume (298.6 m2/g (1.32 cm3/g) ∼ 93.7 m2/g (0.12 cm3/g)), of the macroporous carbon structures produced were approximately proportional to the size (150–1000 nm) of the sacrificial
silica sphere templates used (annealing temp. 550°C). The achieved 550 nm porous carbon structures were examined to function
as potential catalyst carriers and were successfully impregnated with Ag or Pt-Ru on their inner walls after borohydride reduction
at room temperature. In addition, porous carbon patterns were fabricated using the ‘micromolding in capillary’ technique,
which has potential applications in the microreaction technology. 相似文献
17.
赵国林 《吉林化工学院学报》2015,(7)
民办高校有着与公办高校不同的管理体制和机制,为了更加深入、更加有效地开展党的群众路线教育实践活动,要结合特点和发展的实际,科学制定活动方案、强化针对性,真正解决工作中存在的问题,正确地处理几个共性问题,有效凝聚学校发展的力量,推动中国高等教育事业全面健康可持续发展。 相似文献
18.
忽翔 《安徽电气工程职业技术学院学报》2014,(3):18-23
架空输电线路项目扩容改造,当采用倍容导线时,需在技术和经济上对倍容导线进行比较分析。文章对这种导线的种类、特性情况作了介绍,通过在220kV线路上对倍容导线的选择分析,为同类案例的处理提供了借鉴和参考。 相似文献
19.
中厚板在线30通道超声波探伤方法及应用 总被引:3,自引:1,他引:3
介绍了柳钢公司在生产锅炉板、压力容器板过程中,曾试用了6种探伤方法;而研制的30通道在线超声波探伤法不仅可满足国家标准要求,而且能适应生产节奏,并具有快速、准确、简便的特点。 相似文献
20.
The evolutionary design can produce fast and efficient implementations of digital circuits. It is shown in this paper how evolved circuits, optimized for the latency and area, can increase the throughput of a manually designed classifier of application protocols. The classifier is intended for high speed networks operating at 100 Gbps. Because a very low latency is the main design constraint, the classifier is constructed as a combinational circuit in a field programmable gate array (FPGA). The classification is performed using the first packet carrying the application payload. The improvements in latency (and area) obtained by Cartesian genetic programming are validated using a professional FPGA design tool. The quality of classification is evaluated by means of real network data. All results are compared with commonly used classifiers based on regular expressions describing application protocols. 相似文献