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141.
介绍了XMC-3000工业热水锅炉群集散控制系统的硬件组成及特点,描述了锅炉燃烧系统、定压系统的控制方案和系统供热调节模型,最后给出了系统的主要功能。 相似文献
142.
This paper generalizes an algebraic method for the design of a correct compiler to tackle specification and verification of an optimized compiler. The main optimization issues of concern here include the use of existing contents of registers where possible and the identification of common expressions. A register table is introduced in the compiling specification predicates to map each register to an expression whose value is held by it. We define different kinds of predicates to specify compilation of programs, expressions and Boolean tests. A set of theorems relating to these predicates, acting as a correct compiling specification, are presented and an example proof within the refinement algebra of the programming language is given. Based on these theorems, a prototype compiler in Prolog is produced. 相似文献
143.
C Montixi C Langlet AM Bernard J Thimonier C Dubois MA Wurbel JP Chauvin M Pierres HT He 《Canadian Metallurgical Quarterly》1998,17(18):5334-5348
T-cell receptors (TCRs) upon binding to peptide-MHC ligands transduce signals in T lymphocytes. Tyrosine phosphorylations in the cytoplasmic domains of the CD3 (gammadeltaepsilon) and zeta subunits of the TCR complex by Src family kinases initiate the signaling cascades via docking and activation of ZAP-70 kinase and other signaling components. We examined the role of the low-density detergent-insoluble membranes (DIMs) in TCR signaling. Using mouse thymocytes as a model, we characterized the structural organization of DIMs in detail. We then demonstrated that TCR engagement triggered an immediate increase in the amount of TCR/CD3 present in DIMs, which directly involves the engaged receptor complexes. TCR/CD3 recruitment is accompanied by the accumulation of a series of prominent tyrosine-phosphorylated substrates and by an increase of the Lck activity in DIMs. Upon TCR stimulation, the DIM-associated receptor complexes are highly enriched in the hyperphosphorylated p23 zeta chains, contain most of the TCR/CD3-associated, phosphorylation-activated ZAP-70 kinases and seem to integrate into higher order, multiple tyrosine-phosphorylated substrate-containing protein complexes. The TCR/CD3 recruitment was found to depend on the activity of Src family kinases. We thus provide the first demonstration of recuitment of TCR/CD3 to DIMs upon receptor stimulation and propose it as a mechanism whereby TCR engagement is coupled to downstream signaling cascades. 相似文献
144.
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147.
A distributed problem solving system can be characterized as a group of individual cooperating agents running to solve common problems. As dynamic application domains continue to grow in scale and complexity, it becomes more difficult to control the purposeful behavior of agents, especially when unexpected events may occur. This article presents an information and knowledge exchange framework to support distributed problem solving. From the application viewpoint the article concentrates on the stock trading domain; however, many presented solutions can be extended to other dynamic domains. It addresses two important issues: how individual agents should be interconnected so that their resources are efficiently used and their goals accomplished effectively; and how information and knowledge transfer should take place among the agents to allow them to respond successfully to user requests and unexpected external situations. The article introduces an architecture, the MASST system architecture, which supports dynamic information and knowledge exchange among the cooperating agents. The architecture uses a dynamic blackboard as an interagent communication paradigm to facilitate factual data, business rule, and command exchange between cooperating MASST agents. The critical components of the MASST architecture have been implemented and tested in the stock trading domain, and have proven to be a viable solution for distributed problem solving based on cooperating agents 相似文献
148.
铜铅锌银多金属矿湿法分离新工艺 总被引:5,自引:0,他引:5
依据不同金属硫化物氧化分解电位的差异 ,针对某含铜、铅、锌、银复杂多金属硫化矿的难选冶特性 ,对浮选获得的混合精矿采取在线控制浸出过程氧化还原电位的方法 ,分步选择性氯化浸出各有价元素 ,并辅之以沉淀、置换、萃取等工艺 ,使有价金属以较高的回收率得到了有效的分离提取 ,在各工序最佳条件下 ,Cu、Pb、Zn、Ag各金属的浸出率均大于 99 0 % ,元素硫的回收率大于 76% 相似文献
149.
本文描述了一个有效探测面积为100×70cm~2的位置灵敏塑料闪烁探测器阵列,它由两条100×5×1cm和6条100×10×1cm的Pilot U型塑料闪烁体组成。用~(252)Cfα放射源测得10cm宽的闪烁体的时间分辨、位置分辨和能量分辨分别为740ps,5.7cm和60%;5cm宽的闪烁体分别为610ps,4.7cm和40%。 相似文献
150.
Delay-dependent state estimation for delayed neural networks 总被引:3,自引:0,他引:3
Yong He Qing-Guo Wang Min Wu Chong Lin 《Neural Networks, IEEE Transactions on》2006,17(4):1077-1081
In this letter, the delay-dependent state estimation problem for neural networks with time-varying delay is investigated. A delay-dependent criterion is established to estimate the neuron states through available output measurements such that the dynamics of the estimation error is globally exponentially stable. The proposed method is based on the free-weighting matrix approach and is applicable to the case that the derivative of a time-varying delay takes any value. An algorithm is presented to compute the state estimator. Finally, a numerical example is given to demonstrate the effectiveness of this approach and the improvement over existing ones. 相似文献