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基于计数器级联构成大容量计数器研究与实践 被引量:1
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作者 胡桃生 《现代电子技术》 2013年第18期131-133,共3页
在数字系统中,使用得最多的时序电路是计数器。计数器不仅能用于对时序脉冲计数,还可以用于分频、定时、产生节拍脉冲和脉冲序列以及进行数字运算等。实际应用时如需大容量计数器,可通过级联的方式进行扩大。对MSI中规模计数器芯片扩大... 在数字系统中,使用得最多的时序电路是计数器。计数器不仅能用于对时序脉冲计数,还可以用于分频、定时、产生节拍脉冲和脉冲序列以及进行数字运算等。实际应用时如需大容量计数器,可通过级联的方式进行扩大。对MSI中规模计数器芯片扩大的方法主要有两种,一是复位法,二是置位法。无论何种方法,设计的核心是如何写出反馈函数,反馈函数决定着电路的联接。不同的进制,二进制代码反馈函数不同;同步计数器与异步计数器二进制代码反馈函数也不同,因此研究它们的反馈函数对构成大容量计数器是十分重要的。 展开更多
关键词 同步计数 异步计数 级联 容量计数
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浅谈由MSI计数器构成任意进制计数器的方法 被引量:1
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作者 郑筱莉 《新疆职业教育研究》 1996年第1期43-48,共6页
关键词 任意进制计数 计数容量 复位法 进位信号 卡诺图 N进制计数 预置数 功能表 七进制 二进制计数
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计数器功能分析的教学探讨
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作者 徐述 《达县师范高等专科学校学报》 2001年第2期66-68,共3页
本文对计数器功能分析法进行探讨 ,提出了“驱动方程一真值表”分析法 ,避开了求解计算的麻烦 ,达到了“殊途同归”
关键词 计数 功能分析 “驱动方程--真值表” 脉冲数学电路 计数容量
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锂离子电池温度容量效应研究 被引量:1
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作者 雷雨 李锐 +1 位作者 余佳玲 邓岳 《长沙航空职业技术学院学报》 2020年第3期88-92,共5页
由于温度对锂离子电池的内部电化学反应具有重要的影响,锂离子电池具有较明显的温度容量效应。在工程实践中常用的特殊工作点标定模型基础上进行改进,提出了基于电池容量计数下限的非线性估计模型,并进行了实验验证。
关键词 锂离子电池 温度容量效应 容量计数下限 非线性估计模型
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基于C8051F020单片机的高性能多路定标器的研制 被引量:5
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作者 黄顺 赵修良 +3 位作者 赵艳辉 谢菊英 俞红 张美琴 《核技术》 CAS CSCD 北大核心 2008年第5期379-383,共5页
采用扩展计数容量的软件计数方法、软件滤波抗干扰措施及修正晶振振荡偏差的软件定时补偿方法,使用C8051F020单片机和INTEL8254-2计数器芯片,设计了一个16路的多路定标器。测试结果表明,该多路定标器定时准确度高、抗干扰能力强,而且性... 采用扩展计数容量的软件计数方法、软件滤波抗干扰措施及修正晶振振荡偏差的软件定时补偿方法,使用C8051F020单片机和INTEL8254-2计数器芯片,设计了一个16路的多路定标器。测试结果表明,该多路定标器定时准确度高、抗干扰能力强,而且性能稳定,多路定标器的计数容量最高达248–1(约2.8×1014)、最高计数率大于1×107 s-1,这些主要技术性能都优于同类产品。 展开更多
关键词 INTEL8254-2 C8051F020 计数容量 最高计数 软件滤波
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Application of MBAM Neural Network in CNC Machine Fault Diagnosis 被引量:1
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作者 宋刚 胡德金 《Journal of Donghua University(English Edition)》 EI CAS 2004年第4期131-138,共8页
In order to improve the bidirectional associative memory(BAM) performance, a modified BAM model(MBAM) is used to enhance neural network(NN)’s memory capacity and error correction capability, theoretical analysis and ... In order to improve the bidirectional associative memory(BAM) performance, a modified BAM model(MBAM) is used to enhance neural network(NN)’s memory capacity and error correction capability, theoretical analysis and experiment results illuminate that MBAM performs much better than the original BAM. The MBAM is used in computer numeric control(CNC) machine fault diagnosis, it not only can complete fault diagnosis correctly but also have fairly high error correction capability for disturbed Input Information sequence.Moreover MBAM model is a more convenient and effective method of solving the problem of CNC electric system fault diagnosis. 展开更多
关键词 BAM neural network CNC machine electric system memory capacity fault diagnosis Fault tolerance property.
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Transumbilical laparoendoscopic single-site surgery of simple nephrectomy of nonfunctioning kidney: a two-year experience 被引量:1
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作者 Wang Linhui Wu Zhenjie Liu Bing Yang Qing Chen Wei Sheng Haibo Xu Zunli Wang Cheng Sun Yinghao 《Journal of Medical Colleges of PLA(China)》 CAS 2011年第4期213-221,共9页
Background: Laparoendoscopic single-site surgery (LESS) may serve as a potential alternative to conventional laparoscopy and is developing quickly, but still in its infancy. The study is to present our two-year exp... Background: Laparoendoscopic single-site surgery (LESS) may serve as a potential alternative to conventional laparoscopy and is developing quickly, but still in its infancy. The study is to present our two-year experience in transumbilical LESS simple nephrectomy (LESS-SN) for non-functioning kidney, in an effort to evaluate its feasibility, clinical outcomes and potential advantages. Methods: From December 2008 to December 2010, a total of 11 patients with body mass index (BMI)≤30 underwent transumbilical TriPortTM LESS-SN by a single experienced urologist at our institution. The indications for nephrectomy included nonfunctioning kidney associated with ureteropelvic junction stricture (n=l), ureteral calculi (n=6), tuberculosis (n=3), and ureteral stricture (n=l). Patient demographics perioperative and follow-up data were prospectively collected and analyzed. Results: Ten procedures were successfully completed with one patient converted to open surgery due to uncontrollable bleeding. The mean operative time was 189.2 (ranging 100-320 min) with an estimated blood loss of 204.5 (ranging 50-1 000 ml). There were two complications of bleeding (1- intra-, 1- post-). The mean hospitalization after surgery was 7.9 d (ranging 4-17 d) With a regular follow-up of 1, 6, 12, and 24 months after surgery, all patients remained symptom-free with an intra-umbilical scar. Conclusion: Transumbilical LESS simple nephrectomy for nonfunctioning kidney can be accomplished with favorable surgical outcomes and a superiority of cosmesis. However, cases with chronic inflammation are not suitable for initial up-take and should only be attempted by the very experienced laparoscopist. 展开更多
关键词 Laparoendoscopic Single-site Surgery Laparoendoscopic single-site surgery LAPAROSCOPY NEPHRECTOMY
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Effect of Distances from Different Trees Species on the Properties of Mollic Horizon
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作者 Mohammed Ali Fayyadh 《Journal of Agricultural Science and Technology(A)》 2013年第8期581-591,共11页
The study area is located in Duhok province-Kurdistan region-Northern Iraq and including two locations the first location is situated in Galbook village and the vegetation cover is trees of (Quercus aegilops L.), th... The study area is located in Duhok province-Kurdistan region-Northern Iraq and including two locations the first location is situated in Galbook village and the vegetation cover is trees of (Quercus aegilops L.), the second location is situated in Koradeer village that covered with threes of Prunus dulcis (Mill.) Webb.. Disturbed surface soil samples at depth 0-30 cm were collected at four different distances (1, 5, 10 and 15 m) from the tree with randomized selection three trees in each study location. Soil organic matter decreases with increasing distances from tree in both locations under two different trees species, which is attributed to the effect of tree crown. Ordinarily, organic matter content in both locations correspond to the requirements of Mollisols. Statistical analysis of data showed significant differences in organic matter content between locations. Cation exchange capacity is high under tree crown and decreasing with distances from tree in both locations, as a result of decreasing organic matter and increasing calcium carbonate with distances. Commonly soil pH is slightly increased with increasing distances from tree because of increasing calcium carbonate with distances and decreasing organic matter content. Calcium was not uniform with distances and Mg decreasing with distances in both locations. The values of fine clay/coarse clay and fine clay/total clay of soil samples confirm development of the soils under study. Porosity percentage under tree crown is high and decreasing with distances. Soil bulk density was increased with distances in both locations, as a result of decreasing organic matter content with distances. This study aims to explain the effect of tree distances and species on the mollic horizon properties. 展开更多
关键词 Tree species DISTANCES MOLLISOLS physical properties chemical properties.
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PARTIAL REGULARITY FOR OPTIMAL DESIGN PROBLEMS INVOLVING BOTH BULK AND SURFACE ENERGIES
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作者 F.H.LIN R.V.KOHN 《Chinese Annals of Mathematics,Series B》 SCIE CSCD 1999年第2期137-158,共22页
This paper studies a class of variational problems which involving both bulk and surfaceenergies. The bulk energy is of Dirichlet type though it can be in very general forms allowingunknowns to be scalar or vectors.Th... This paper studies a class of variational problems which involving both bulk and surfaceenergies. The bulk energy is of Dirichlet type though it can be in very general forms allowingunknowns to be scalar or vectors.The surface energy is an arbitrary elliptic parametric integralwhich is defined on a free interface. One also allows other constraints such as volumes of partitioning sets. One establishes the existence and regularity theory, in particular, the regularityof the free interface of such problems. 展开更多
关键词 Partial regularity Optimal design problem Nonlinear variational problems
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