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31.
电力系统暂态稳定性概率评估方法的研究   总被引:7,自引:0,他引:7  
传统的暂态稳定性分析方法难以反映电力系统故障的随机特性.暂态稳定评估的概率方法是对传统方法的重要补充,但其计算量较大.文章通过分析故障切除时间的统计特性和不同类型故障的严重程度提出了基于归一化暂态能量函数的暂态稳定性概率评估策略.该策略只需对系统中的一'小部分严重故障进行暂态稳定性计算,因而能够极大地提高暂态稳定概率分析的效率.文章通过新英格兰10机39节点典型系统的算例说明了该评估策略的有效性和实用性.  相似文献   
32.
Metal-based anticancer agents with non-DNA targets are anticipated for overcoming cisplatin resistance problems. Gold complexes are generally known to undergo ligand exchange or redox reactions with thiols, and hence, are potentially useful agents that could target thiol-containing enzymes, but not DNA. Recent studies have shown that deubiquitinases (DUBs), key enzymes regulating proteasome-related protein homeostasis, are potential anticancer targets of both gold(I) and gold(III) complexes. In this review, the current status of gold complexes as DUB inhibitors is discussed. In particular, auranofin and cyclometalated gold(III) complexes containing dithiocarbamate ligands (e.g., [(AuIII(C N)(DEDT)]+, HC N=2-phenylpyridine, DEDT=diethyldithiocarbamate) are highlighted as examples of DUB inhibitors. The mechanisms of their anticancer action, together with in vitro and/or in vivo antitumor potencies, are also explored.  相似文献   
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Some experimental results in GaAs DH lasers having a stable, long operating-time, such as nonlinear superhigh differential quantum efficiency, the behavior of light output saturation and sudden growth again in the same filament, strong self-sustained pulsation, and so on, are presented. A model of double filaments caused by the non-uniform distribution of aluminum in the active layer of the laser diode is presented to explain their anomalous behavior qualitatively.  相似文献   
36.
Research has found that while flexibility is purported to be a prime advantage of flexible manufacturing systems (FMS), it has not yet become a major competitive priority for American and European manufacturers. Moreover, many installed systems either are not very flexible or do not use the available flexibility to the best advantages. We suspect that inappropriate application of the conventional production management concepts to FMS is one of the major factors that hinders current FMSs from capturing their key advantage: flexibility. This paper takes a first step to examine why the conventional job shop loading and fixed routeing concepts fail to capture the flexibility of FMS. Once problems are identified we suggest ways to exploit the FMS flexibility. We further conduct an experiment to investigate FMS performance under different manufacturing policies and operating conditions. The results indicate that the performance of an FMS greatly diminishes when the conventional job shop loading and fixed routeing concepts are applied. This is because the inherent flexibility of the FMS is not fully utilized. Moreover, the operating conditions such as tooling duplication levels and operation processing time variation could also significantly affect the FMS performance.  相似文献   
37.
An 8-Gb multi-level NAND Flash memory with 4-level programmed cells has been developed successfully. The cost-effective small chip has been fabricated in 70-nm CMOS technology. To decrease the chip size, a one-sided pad arrangement with compacted core architecture and a block address expansion scheme without block redundancy replacement have been introduced. With these methods, the chip size has been reduced to 146 mm/sup 2/, which is 4.9% smaller than the conventional chip. In terms of performance, the program throughput reaches 6 MB/s at 4-KB page operation, which is significantly faster than previously reported and very competitive with binary Flash memories. This high performance has been achieved by the combination of the multi-level cell (MLC) programming with write caches and with the program voltage compensation technique for neighboring select transistors. The read throughput reaches 60 MB/s using 16I/O configuration.  相似文献   
38.
Volatile components in fresh-picked blue crabmeat and processing byproduct were compared by simultaneous steam distillation-solvent extraction/gas chromatography/mass spectrometry (SDE/GC/MS). Compounds were identified in crabmeat (771 and by-product (80) of which 58 were common to both. Some compounds 154) were identified for the first time in crab. Trimethylamine, four alkanes (C15–C17, C19), and indole were highest (> 50 ng/g)) in crabmeat, while trimethylamine, carbon disulfide, dimethyltrisulfide, two alkanes (C15 and C17), geranylacetone, and 1–dodecanol were highest in by-product. Of compounds from both samples, 23 were higher in by-product and 7 were higher in the meat. Crab processing by-product may be a good source for volatile flavor recovery.  相似文献   
39.
D-Erythroascorbic Acid in Bakers'Yeast and Effects on Wheat Dough   总被引:1,自引:0,他引:1  
Extraction of hydrated and freeze-dried bakers’yeast yielded ~ 50 μg erythroascorbic acid (EAA) and 5 μg ascorbic acid (AA)/g dry yeast as determined by HPLC with electrochemical detection. D-EAA (82 ppm based on flour) slightly increased the flow of dough as rest time increased. Gluten isolated from a flour-water dough containing 82 ppm D-EAA or 100 ppm Lcysteine stretched at a faster rate than control gluten. EAA like AA did not change dough development time. Unlike AA, EAA showed neither oxidizing effect on dough and gluten nor improving effects on bread.  相似文献   
40.
This paper presents the development of a daily scheduling tool, Electronic Research and Service Organization Fab Scheduler (ERSOFS), for a research and development (R&D) pilot line of semiconductor wafer fabrication. An integer programming problem formulation is first given, which captures the salient features such as high variety and very low volume, cyclic process flows, batching at diffusion machines, single mask for each photolithography operation, loop test and engineering splitting and merging of wafer lots. A solution methodology based on Chang and Liao's approach [1994] for scheduling flexible flow shops is then extended to this class of problems. The solution methodology is implemented and validated in an R&D fab. Results indicate that ERSOFS efficiently generates schedules of high quality. The rescheduling function of ERSOFS provides fast and smooth adjustments of schedules to cope with the. high production uncertainties in an R&D fab. Analysis of the algorithmic properties demonstrates the potential of ERSOFS for application to larger fabs  相似文献   
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