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71.
一种基于折叠计数器重新播种的确定自测试方案 总被引:35,自引:3,他引:32
提出了一种基于扫描自测试的确定与混合模式新方案,这种方案依赖于一个新型的模式生成器,它主要配备一个可编程的约翰逊计数器,称之为折叠计数器。这种新技术首先使用一个小的线性反馈移位寄存器(LFSR),生成伪随机测试模式测试容易测试的故障,并且获得一个硬故障测试立方集T;其次采用经典的输入精简技术,集合T的测试立方宽度可以被压缩;最终为了能够找出合理的小数目折叠计数器种子,来生成这个确定的测试立方集T,给出了其理论背景和实用算法。试验结果表明,这个所建议的方案与先前所公布的基于线性反馈移位寄存器和约翰逊计数器的重新播种方法相比,具有非常出色的结果。因此它提供了一种有效的、弹性的基于扫描的自测试解。 相似文献
72.
ZENG Ai-xiang w XIONG Wei-hao * . Department of Chemistry Changsha University of Science Technology Changsha China . State Kay Laboratory of Die &Mould Technology Huazhong University of Science Technology Wuhan China 《材料热处理学报》2004,25(5)
FLY ASH CENOSPHERES are primarily a by-productin power generation plants.Research is in progress toeffectively use this by-product to produce new usableand profitable materials as they pose major disposaland environmental problems.Fly ash cenospheres areunique,property stable,non-toxic,non-metallic hollowmicro-particles.Due to the unique hollow structure andphysical mechanics properties,Cu^Ag and other metalsare often coated on cenospheres to produce lightweightmetal matrix composites,w… 相似文献
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KH+*DZUO Zhen-lin ZHANG Jing LIANG Xiong-jianEconomics & Management School Beijing University of Posts & Telecommunications Beijing P.R. China 《中国邮电高校学报(英文版)》2005,12(4)
1IntroductionFacing the rapid development of social economy andscience technology China Post needs wide cooperation a-mong industries to gain competitive advantage and de-velopment space , which appeals the leading-edge tele-comindustry to become its partner .In some fields Chi-na Post and the Telecoms have launched business coop-eration which stays onlowlevel ,so for China Post it isurgent to establish relationship to the Telecoms onstrategiclevel presently,which will build win-winsitua-ti… 相似文献
75.
P. Zou* W.B. Zhang Kunming University of Science Technology Kunming China T. Lei J.K. Wang Technology Center Yunnan Metallurgy Group Co. Ltd. Kunming China 《金属学报(英文版)》2006,(5)
1. Introduction There have been two difficulties encountered with the leaching of low-grade primary chalcopyrite oresusingmesophile culture-thiobacillusferrooxidans(Tf) and thiobacillusthiooxidans(Tt), and so on[1-3].The first is the poor leaching effect and the second is the resultant increase in temperature during the middle and the later phase ofheap-leachingperiod, which is unfavorable for the growth and the culture of Tf and Tt. Being widely used for mineral leaching at present, Tf and … 相似文献
76.
SHEN Yanxia ZHANG Yongxue* LAN Xiaoli CAO Wei 《核技术(英文版)》2007,18(2):101-106
To explore the preparation method of liposome-coated 99mTc-labeled antisense oligonucleotide (ASON),targeteing the proliferating cell nuclear antigen (PCNA), and to explore the biological characteristics and the uptake kinetics of a radiolabeled probe in vascular smooth muscle cells, an 18-base single-stranded antisense oligonucleotide targeting PCNA mRNA and the complementary strand (sense oligonucleotide, SON) were synthesized. The ASON (SON) was labeled with 99mTc, by conjugating the bifunctional chelator (hydrazino nicotinamide, HYNIC), and purified through a gel filtration column of Sephadex G-25. The product was then encapsulated in cationic liposome (oligofectamineTM). The radiolabeling efficiency, radiochemical purity, stability of the liposome-coated 99mTc-HYNIC-ASON in a phosphate buffered solution (PBS), and fresh human serum and its uptake rate were studied. There was no significant difference between the 99mTc radiolabeling efficiencies of HYNIC-ASON and HYNIC-SON, which were 60.04% ± 1.92% and 59.60% ± 2.53%, respectively (P > 0.05, n = 5). The radiochemical purity of the liposome-coated 99mTc-HYNIC-ASON was 94.70% ± 1.90% (n = 5). And after incubation with PBS and fresh human seAt 90 min after transfection, the uptake rate of the liposome-coated 99mTc-HYNIC-ASON reached its peak of 83.8% ±5.92% in vascular smooth muscle cells (VSMCs) and was much higher than that of the nonliposome-coated 99mTc-HYNIC-ASON, which was 11.16% ± 0.54% (P < 0.01, n = 4). The labeling method of PCNA ASON (SON) conjugated by HYNIC has been proved successful. The liposome was able to enhance the ASON (SON) uptake in VSMCs,and could be widely used as a safe, convenient, effective gene transfer carrier. 相似文献
77.
铁矿石卖方确信年铁矿石谈判的结果将是价格上扬 原因是焦煤供应商已成功地提高了 年焦煤供应价。今年日本的焦煤供应价平均上扬 % 尽管北美焦煤商在欧洲的售价被大幅度压低 但其价格仍高于日本的市场价格。铁矿石供应商将不会期望铁矿石价格如焦煤价格在欧洲有相同的上涨 届时第 轮铁矿石价格谈判将在日本举行。据称 到目前为止 仅有里奥*廷托集团的哈默斯利公司在 月初第三轮谈判时 在日本提出的价格表上将价格提高 .%。尽管这一数字未被证实 但贸易商说该数字相当可靠。 《工程建设》2001,33(3):12
铁矿石卖方确信 2001 年铁矿石谈判的结果将是价格上扬,原因是焦煤供应商已成功地提高了 2001 年焦煤供应价。今年日本的焦煤供应价平均上扬 8%,尽管北美焦煤商在欧洲的售价被大幅度压低,但其价格仍高于日本的市场价格。铁矿石供应商将不会期望铁矿石价格如焦煤价格在欧洲有相同的上涨,届时第 4 轮铁矿石价格谈判将在日本举行。据称,到目前为止,仅有里奥*廷托集团的哈默斯利公司在 2 月初第三轮谈判时,在日本提出的价格表上将价格提高 7.5%。尽管这一数字未被证实,但贸易商说该数字相当可靠。
(郑 英) 相似文献
78.
掌握涂层界面应力状态有助于涂层开发应用和提高其工作性能与使用寿命。将数学方法应用于应力应变分析,提出了一种高效、简便的界面应力算法。 相似文献
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80.
设计合成了一个氨基葡萄糖修饰的水溶性锌离子荧光增强型化学传感器,并借助核磁共振谱和质谱对其结构进行了表征,利用荧光光谱法研究了该传感器对不同金属离子的荧光响应。结果显示,在4-羟乙基哌嗪乙磺酸(HEPES)缓冲溶液中,该传感器能与Zn2+配位且在发射波长490 nm处荧光显著增强,除Cu2+、Ni2+、Co2+和Cr3+对此配合物荧光强度有不同程度猝灭外,其他金属离子的加入均没有引起其明显变化,说明传感器对Zn2+有较好的选择性;同时,Job曲线表明二者形成了结合比为2∶1的稳定配合物。 相似文献