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991.
The paper presents sufficient conditions for modular (supervisory) control synthesis to equal global control synthesis. In modular control synthesis a supervisory control is synthesized for each module separately and the supervisory control consists of the parallel composition of the modular supervisory controls. The general case of the specification that is indecomposable and not necessarily contained in the plant language, which is often the case in practice, is considered. The usual assumption that all shared events are controllable is relaxed by introducing two new structural conditions relying on the global mutual controllability condition. The novel concept used as a sufficient structural condition is strong global mutual controllability. The main result uses a weaker condition called global mutual controllability together with local consistency of the specification. An example illustrates the approach. 相似文献
992.
993.
最近有些读者朋友问:现在微软为什么这么霸道,连显示器都要通过它的认证,没有通过Windows Vista认证的液晶显示器会有什么不同吗?液晶显示器和Windows Vista操作系统之间到底有什么必要的联系呢?通过Windows Vista认证的显示器又有什么好处呢?针对上述种种疑问,今天我们将为大家一一解答。 相似文献
994.
本文分析了LVS中的各种负载调度策略,针对其不足之处提出了一种新的动态负载调度策略.该策略以单位时间流量为依据,对服务器健康状况进行分级,并根据连续检测的结果在各级之间进行转换. 相似文献
995.
This paper deals with the creep effect on dynamic visco-elastic properties of short fibre reinforced polymer SMC composite. The vibration-creep-vibration test procedure was applied to examine the influence of creep on dynamic modulus E and loss tangent tg of the material. The results show that creep causes appreciable influence on E and tg. 相似文献
996.
I. H. Dmukhovs'ka 《Materials Science》1994,29(6):596-599
We determined the relative elongation () and ultimate strength (u) of hollow Armco iron specimens and Armco iron specimens filled with indium at high temperatures in a vacuum. It was shown that indium embrittles Armco iron in the temperature range 850–950°C. The lowest values of were obtained at a temperature of 925°C, where a small amount of the -phase is observed in the structure of strained specimens. The high-temperature liquid metal embrittlement of Armco iron is caused by an indiummelt-induced decrease in the flow stress, which localizes strains in the -phase and initiates its premature cracking. On the basis of metallographic investigations, we made the conclusion that corrosion is not responsible for the high-temperature liquid metal embrittlement of Armco iron.Karpenko Physicomechanical Institute, Ukrainian Academy of Sciences, L'viv. Translated from Fiziko-Khimicheskaya Mekhanika Materialov, Vol. 29, No. 6, pp. 41–45, November–December, 1993. 相似文献
997.
A new type of silicon membrane structure was fabricated using wafer fusion bonding and two-step electrochemical etch-stopping methods. An active wafer of p-type epi/n-type epi/p-type substrate was first elctrochemically etched to form a shallow cavity on the p-type epitaxial layer. Then, the cavity-formed side was fusionally bonded with p-type silicon working wafer and, afterwards, the p-type substrate of the active wafer part was removed by a second electrochemical etch-stopping leaving only the n-type membrane on the shallow cavity. Using the new membrane structure in mechanical sensors, more precise control of cavity depth and membrane thickness was achievable and the influence of crystalline imperfections on the sensing circuits located near the bonding seam was avoidable. 相似文献
998.
We have shown that dicyanogold(I), [Au(CN)(2)](-) is a common metabolite found in blood and urine samples of patients treated with different gold based drugs. Some patients have high levels of gold within their red blood cells (RBCs). Size exclusion and C18 reversed phase chromatography show that the majority of the gold in RBC lysates is bound to protein, but small molecules such as dicyanogold(I) and gold-glutathione complexes are also present. Dicyanogold incubation with red blood cells in vitro leads to a rapid and complete uptake of gold. This uptake is unaffected by DIDS, an inhibitor of the anion channel, but is blocked by the addition of external cyanide. Dicyanogold is also readily taken up by H9 cells, a continuous CD(4+) cell line. This uptake is significantly inhibited by N-ethylmaleimide, suggesting a requirement for sulfhydryl groups. Dicyanogold inhibits the replication of the AIDS virus, HIV, in a cell culture model. 相似文献
999.
1000.