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11.
胡莲  苏伯珙 《计算机学报》1992,15(2):128-136
本文给出平行结构类问题及其求解系统的形式化描述,讨论了此类问题的分解与任务分布,并提出了一种IPD算法(Improved Problem Decomposition).该算法从规模上将问题分解为若干性质相同的任务,按就近原则将任务预分布到系统中各结点上,并通过启发式状态空间查找方法进行负载调整,使系统负载平衡.试验表明:IPD算法的分解分布结果负载平衡,系统潜在协作量小.  相似文献   
12.
基于集散控制的分布式电源并网监控系统研究   总被引:1,自引:0,他引:1  
鉴于分布式电源分散的广阔性,选择了基于集散控制的GPRS无线通信网络,保证了监控系统的实时性;针对大功率分布式电源的并网问题,从电能重要性不断增强和安全性方面考虑,提出了监控系统主站和基站的设计方案,在并网动作和并网之后对分布式电源的发电情况以及各参数进行监控,使电力系统在并网动作前后免受过大冲击,有效地提高了并网的稳定性和安全性;经过软件仿真测试,证明该方案切实可行。  相似文献   
13.
介绍基于TMS320VC5509A的冶金企业谐波分析仪系统的研究,并根据工业现场数据传输的要求,选出谐波分析仪合适的以太网数据传输方式,实现了冶金企业对生产设备谐波监测的要求。  相似文献   
14.
In this paper,some engineering problems arising from hydraulics and the design of hy-draulic structures are proposed,in accordance with the viewpoint of cybernetics,as the shape-controlproblems for distributed parameter system(DPS),whose solution is obtained using BEM-Optimizationtechnique.As a classical example,the problem of flow over a weir is converted first into a shape-con-trol problem,which is then converted into an optimization problem to be solved.Computational resultsshow that the BEM-Optimization method is an efficient way to solve shape-control problems for DPS,which not only can avoid the tedious process of trial and error or iteration,but also has high accuracyand less CPU consumption.For the problem of flow over a weir,the stream function,the free surfaceprofile and the unknown flow-rate can be found simultaneously.  相似文献   
15.
矿山数字化摄影测量系统的设计与实现   总被引:2,自引:0,他引:2  
本文主要阐述矿山数字化摄影测量的基本原理、方法、矿山数字化摄影系统的硬件配置及软件组成,扼要介绍了系统所采用的算法及相关技术。  相似文献   
16.
煤炭生物絮凝絮体分形试验研究   总被引:2,自引:0,他引:2       下载免费PDF全文
张东晨  侯志翔  周倩倩  闫佳 《煤炭学报》2015,40(5):1148-1152
为解决化工产品类絮凝剂的大量使用会对环境造成严重污染的问题,采用对煤炭具有良好絮凝作用的枯草芽孢杆菌作为生物絮凝剂产生菌,开展煤炭生物絮凝试验和絮体分形试验研究。通过对生物絮凝的絮体进行显微图像采集与分析,利用絮凝体的投影面积与最大长度的函数关系计算絮凝体的分形维数。研究发现,枯草芽孢杆菌絮凝剂用量和絮体分形维数与煤泥水透光率之间具有显著的相关性。研究结果表明,以絮凝体分形维数为主控指标,可以实现对枯草芽孢杆菌絮凝剂的定量控制,能够比较客观地反映煤泥水的絮凝沉降过程。  相似文献   
17.
The analysis of a 32 kb DNA fragment from cosmid 2G12 on the left arm of chromosome XII identifies 14 open reading frames (ORFs) numbered L0948 to L1325, a new tRNA for proline, a delta remnant and two putative ARS. Six ORFs have been previously identified: HSP104, SSA2, SPA2, KNS1, DPS1/APS and SDC25. Three putative ORFs have significant homology with known proteins: L0968 is a new member of the very large ‘seripauperins’ family, comprising at least 20 yeast members; L1313 is a new ABC transporter highly homologous to the yeast cadmium resistance protein Ycf1p and to the human multidrug resistance protein hMRP1; the C-terminal part of L1325 present in our sequence is very homologous to the fruit fly abdominal segment formation protein Pumilio. Finally, two ORFs, L1201 and L1205, have weak homology with two yeast hypothetical proteins of unknown function identified by the yeast systematic sequencing genome. Since our nucleotide sequence overlaps by 11·6 kb the cosmid 2B18 sequenced by Miosga and Zimmerman (1996) on the right end, we have not reported here the analysis of the ORFs L1313, L1321 and L1325. The complete nucleotide sequence of 32,088 bp and the deduced ORFs were submitted to the EMBL database under Accession Number X97560.© 1997 John Wiley & Sons, Ltd.  相似文献   
18.
为解决使用传统电镀液配方进行挠性板通孔电镀时出现的均镀能力(TP)差等问题,本文基于加速剂聚二硫二丙烷磺酸钠(SPS)、N,N-二甲基二硫代甲酰胺丙烷磺酸钠(DPS)的电化学性能测试,研究了整平剂对挠性板通孔电镀效果的影响,并对无整平剂的镀液体系中挠性板通孔电镀的影响因素进行了分析讨论。结果表明,SPS具有持续性的加速作用,是典型的加速剂,而DPS在高浓度条件下呈现出抑制效果,具有加速-整平双重特性;无整平剂体系下挠性板通孔的电镀效果(TP≥200%)明显要比有整平剂体系下的电镀效果(TP≈100%)要好,但是无整平剂条件下所得的铜镀层质量差;通过在无整平剂体系中加入DPS,利用DPS的微整平性能能够有效改善镀层质量。提高镀液中的铜离子浓度,降低酸的浓度、采用小电流密度、短时间电镀以及低气流量有利于提高通孔电镀的均镀能力。  相似文献   
19.
Many technological difficulties exist in the field of rapid prototyping (RP) technology when making large-scale prototypes. The manufacturing efficiency is the main problem, and the process implemention and RP equipment also present difficulties. In this paper, the concept of divisional parallel scan is presented. Laminated object manufacturing (LOM) technology is used for the basic forming process and has been improved continuously through practice. Static divisional scan technology was also better developed to dynamic divisional scan technology, which can help in achieving the object of improving work efficiency and optimising design.  相似文献   
20.
Temperature and selenium are two environmental parameters that potentially affect reproduction and stock recruitment of sturgeon in the San Francisco Bay/Delta Estuary. To identify proteins whose expression is modified by these environmental stressors, we performed a proteomic analysis on larval green and white sturgeons exposed to 18 or 26 °C and micro-injected with Seleno-L-Methionine to reach 8 µg g1 selenium body burden, with L-Methionine as a control. Selenium and high temperature induced mortalities and abnormal morphologies in both species, with a higher mortality in green sturgeon. Larval proteins were separated by two-dimensional gel electrophoresis and differential abundances were detected following spot quantitation and hierarchical cluster analysis. In green sturgeon, 34 of 551 protein spots detected on gels showed a variation in abundance whereas in white sturgeon only 9 of 580 protein spots were differentially expressed (P < 0.01). Gel replicates were first grouped according to heat treatment. Fifteen of these spots were identified using MALDI TOF/TOF mass spectrometry. Proteins involved in protein folding, protein synthesis, protein degradation, ATP supply and structural proteins changed in abundance in response to heat and/or selenium. 40S ribosomal protein SA, FK506-binding protein 10, 65 kDa regulatory subunit A of protein phosphatase 2, protein disulfide isomerase, stress-induced-phosphoprotein 1, suppression of tumorigenicity 13 and collagen type II alpha 1, were differentially expressed in high temperature treatment only. Serine/arginine repetitive matrix protein 1, creatine kinase, serine peptidase inhibitor Kazal type 5 and HSP90 were sensitive to combined temperature and selenium exposure. Valosin-containing protein, a protein involved in aggresome formation and in protein quality control decreased more than 50% in response to selenium treatment. Potential use of such proteins as biomarkers of environmental stressors in larval sturgeons could indicate early warning signals preceding population decline.  相似文献   
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