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21.
This article proposes a novel parallel, hardware-oriented deadlock detection algorithm for multiprocessor system-on-chips. The proposed algorithm takes full advantage of hardware parallelism in computation and maintains information needed by deadlock detection through classifying all resource allocation events and performing class specific operations, which together make the overall run-time complexity of the new method O(1). We implement the proposed algorithm in Verilog HDL and demonstrate in the simulation that each algorithm invocation takes at most four clock cycles in hardware. 相似文献
22.
Xin Song Xiaoyu Qi Bin Hao Yinbo Qu 《European Journal of Lipid Science and Technology》2008,110(12):1095-1101
Although lipases are widely applied in a wide variety of reactions, available information on the factors that are responsible for the substrate specificities of lipases from different sources is scarce. In this paper, nine lipase‐producing microorganism strains were isolated from oil‐containing samples. The properties of these enzymes, including pH optima, temperature optima, thermal stability, and pH stability, vary significantly with the different sources from which these lipases were isolated. The substrate specificities of the nine lipases, including fatty acid and positional specificities, were also studied. The fatty acid specificities of the nine lipases were observably different toward 15 substrates with different carbon chain lengths, different saturation degrees and different side chains. The lipases from S3 Penicillium citrinum (PCL), MJ1 Aspergillus niger (ANL), MJ2 Aspergillus oryzae (AOL), YM Bacillus coughing (BCL), S9 Geotrichum candidum (GCL), and S11 Candida lypolytica (CLL) showed the strongest specificities to short‐chain esters, and the other lipases showed strong selectivity for medium‐ or long‐chain and branched esters. The positional specificities were examined by analyzing the hydrolytic products of triolein catalyzed by the nine lipases, using TLC. The lipases can be mainly classified into two groups by their specificities for the ester bond at position 2 of triglycerides; one group can selectively hydrolyze the ester bond at position 2 of the triglycerides, the other group cannot. All these nine lipases were divided into four groups by hierarchical clustering analysis on the basis of the results of fatty acid and positional specificities. 相似文献
23.
Hydrothermal Synthesis of Magnesium Aluminate Platelets 总被引:1,自引:0,他引:1
Zhi-Zhan Chen Er-Wei Shi Hua-Wei Zhang Yong Zhang Xiang-Biao Li Xue-Chao Liu Bing Xiao 《Journal of the American Ceramic Society》2006,89(12):3635-3637
Magnesium aluminate (MgAl2 O4 ) platelets were first synthesized by hydrothermal treatment of γ-AlO(OH) in a magnesium nitrate aqueous solution at 400°C. The platelets are 100–200 nm in width and 25 nm in thickness. The influence of temperature, the anions of the magnesium salt, the amount of magnesium salt, and precursor pH on the formation of such structure was investigated. The experimental results indicated that the anions of the magnesium salt and precursor pH could have a significant influence on the growth of MgAl2 O4 . MgAl2 O4 formation followed the in situ transformation mechanism, which was the reason why the MgAl2 O4 crystallites had a platelet morphology. 相似文献
24.
25.
本文主要完成了液态金属钠高温沸腾实验回路的应力分析与计算,确定了回路高温区连接管系的布置型式和支吊架系统,是该回路总体设计的重要组成部分。 相似文献
26.
ElectronmicroscopicobservationsandDNAchainfragmentationstudiesonapoptosisinbonetumorcelsinducedby153SmEDTMPZhuShouPeng,Xia... 相似文献
27.
Yufei Tao Xiaokui Xiao Jian Pei 《Knowledge and Data Engineering, IEEE Transactions on》2007,19(8):1072-1088
Skyline and top-k queries are two popular operations for preference retrieval. In practice, applications that require these operations usually provide numerous candidate attributes, whereas, depending on their interests, users may issue queries regarding different subsets of the dimensions. The existing algorithms are inadequate for subspace skyline/top-k search because they have at least one of the following defects: 1) they require scanning the entire database at least once, 2) they are optimized for one subspace but incur significant overhead for other subspaces, or 3) they demand expensive maintenance cost or space consumption. In this paper, we propose a technique SUBSKY, which settles both types of queries by using purely relational technologies. The core of SUBSKY is a transformation that converts multidimensional data to one-dimensional (1D) values. These values are indexed by a simple B-tree, which allows us to answer subspace queries by accessing a fraction of the database. SUBSKY entails low maintenance overhead, which equals the cost of updating a traditional B-tree. Extensive experiments with real data confirm that our technique outperforms alternative solutions significantly in both efficiency and scalability. 相似文献
28.
主要介绍了热电厂近几年来在技术管理方面取得的主要工作经验,以及围绕生产经营开展科技创新所取得的成绩,并且针对当前形势,进一步提出了热电厂今后一个时期科技工作的指导思想、任务目标和措施。 相似文献
29.
晓慧 《网络安全技术与应用》2007,(6):8
近日,“网上银行反欺诈联动机制”联合声明暨“2007放心安全用网银联合宣传年”启动新闻发布会在北京召开,此次会议由“放心安全用网银联合宣传年”活动组委会主办。“放心安全用网银联合宣传年”活动是 相似文献
30.