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PLC控制系统的干扰源分析及抑制干扰对策

电力自动化设备 2006年第8期26卷 8-11页

作者：张存礼济宁职业技术学院机电系山东济宁272037

可编程逻辑控制器(PLC)控制系统的可靠性直接影响到工业企业的安全生产和经济运行,而系统的抗干扰能力是整个系统可靠运行的关键。论述了PLC控制系统中的干扰源主要来自空间辐射、系统外引线、PLC系统内部3个方面,并分析了这些干扰在控... 详细信息

可编程逻辑控制器(PLC)控制系统的可靠性直接影响到工业企业的安全生产和经济运行,而系统的抗干扰能力是整个系统可靠运行的关键。论述了PLC控制系统中的干扰源主要来自空间辐射、系统外引线、PLC系统内部3个方面,并分析了这些干扰在控制系统中的影响,提出了几种抗干扰的主要措施,即电源部分的拦截、采用合适的电缆以及电缆的正确敷设、完善而合理的接地系统以及软件解除干扰。

关键词：可编程逻辑控制器干扰源抗干扰

Assessment of Land Suitability Potentials for Selecting Winter Wheat Cultivation Areas in Beijing,China,Using RS and GIS

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Agricultural Sciences in China 2011年第9期10卷 1419-1430页

作者： WANG Da-cheng li cun-jun SONG Xiao-yu WANG Ji-hua YANG Xiao-dong HUANG Wen-jiang WANG Jun-ying ZHOU Ji-hong Institute of Agricultural Remote Sensing and Information Technology Zhejiang University Hangzhou 310029 P.R. China Beijing Research Center for Information Technology in Agriculture Beijing 100097 P.R.China Agricultural Technology Extension Station in Beijing Beijing 100029 P.R.China

It is very important to provide reference basis for winter wheat quality regionalization of cultivation area. The aim of this article was based on factors affecting wheat quality and setting realistic spatial models in each part of the land for assessment of land suitability potentials in Beijing, China. The study employed artificial neural network （ANN） analysis to select factors and evaluate the relative importance of selected environment factors on wheat grain quality. The spatial models were developed and demonstrated their use in selecting the most suitable areas for the winter wheat cultivation. The strategy overcomes the non-accurate traditional statistical methods. Satellite images, toposheet, and ancillary data of the study area were used to find tillable land. These categories were formed by integrating the various layers with corresponding weights in geographical information system （GIS）. An integrated land suitability potential （LSP） index was computed considering the contribution of various parameters of land suitability. The study demonstrated that the tillable land could be categorized into spatially distributed agriculture potential zones based on soil nutrient and assembled weather factors using RS and GIS as not suitable, marginally suitable, moderately suitable, suitable, and highly suitable by adopting the logical criteria. The sort of land distribution map made by the factors with their weights showed more truthfulness.

关键词： LSP ANN suitable areas wheat RS and GIS

A new cobalt-radical complex based on pyrimidinyl substituted nitronyl nitroxide ligand

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A new cobalt-radical complex based on pyrimidinyl substitute...

中国化学会第十届全国无机化学学术会议

作者： Pei Jing Guifang Sun li-cun li Department of Chemistry Nankai University

The studies on molecular materials with optical, electronic and magnetic properties have developed rapidly. Combining metal and nitronyl nitroxide radical within the same molecular entity is one of the effective ways to construct molecular magnetic materials. In this work, we choose pyrimidinyl substituted nitronyl nitrixide ligand to react with Co(hfac) to obtain a new transition metal-radical complex {[Co(hfac)](NIT-Pyrim)}. The structure of the complex is shown in Figure 1. In this asymmetry unit, two Co(hfac) coordinate with O and N atoms from two NIT-Pyrim forming cyclic dimers. And each dimer is bridged by N from two NIT-Pyrim to make a special structure, one-dimensional transition cobalt ring chain. As shown in Figure 2, magnetic studies show that Co complex displays frequency dependent magnetic susceptibilities, indicating slow magnetic relaxation behavior.

关键词： transition metal nitronyl nitroxide cyclic chain magnetization

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文学生产视域下的网络文学生产与创新

学习与实践 2019年第8期 117-123页

作者：李存南阳理工学院文法学院

互联网背景下,日益发展的媒介环境深刻建构了网络文学生产。基于文学生产视角观照网络文学,将生产形态、生产者、生产内容等影响文学生产力的主要因素作为研究对象,可以发现媒介建构下网络文学生产的新特点,即网络文学生产媒介形态的多... 详细信息

互联网背景下,日益发展的媒介环境深刻建构了网络文学生产。基于文学生产视角观照网络文学,将生产形态、生产者、生产内容等影响文学生产力的主要因素作为研究对象,可以发现媒介建构下网络文学生产的新特点,即网络文学生产媒介形态的多元多维,网络文学生产参与者在即时互动下的融合,以及网络文学生产力图反映网络原住民的生活体验和价值认同。这些新的特质的结合将促进中国网络文学生产机制的整体提升。

关键词：媒介环境网络文学生产创新

The pre-Kasai procedure in living donor liver transplantation for children with biliary atresia

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Hepatobiliary & Pancreatic Diseases International 2013年第1期12卷 47-53页

作者： Qiao Wang Lu-Nan Yan Ming-Man Zhang Wen-Tao Wang Ji-Chun Zhao Cong-Lun Pu Ying-cun li Quan Kang liver Transplantation Division Department of SurgeryWest China HospitalSichuan University Department of Hepatobiliary Surgery Children's HospitalChongqing Medical University

BACKGROUND:Biliary atresia(BA) is a major cause of chronic cholestasis,a fatal disorder in *** study was undertaken to evaluate the safety and effectiveness of primary living donor liver transplantation(LDLT) in comparison with the traditional first-line treatment,the Kasai ***:We assessed 28 children with BA at age of less than two years(3-21.3 months) who had undergone LDLT in two hospitals in Southwest China during the period of *** children who had had primary LDLT were included in a primary LDLT group,and ten children who had undergone the Kasai operation in a pre-Kasai *** patients were followed up after discharge from the *** records of the BA patients and donors were ***:The time of follow-up ranged 12-44.5 months with a median of 31 *** 30-day and 1-year survival rates were 85.7% and 78.6%,*** was no significant difference in the 30-day or 1-year survival between the two groups(83.3% vs 90% and 77.8% vs 80%,P>0.05).The main cause of death was hepatic artery *** were more patients with complications who required intensive medical care or re-operation in the pre-Kasai group(8,80%) than in the primary LDLT group(9,50%)(P=0.226).But no significant differences were observed in operating time(9.3 vs 8.9 hours,P=0.77),intraoperative blood loss(208.6 vs 197.0 mL,P=0.84) and blood transfusion(105.6 vs 100.0 mL,P=0.91) between the two *** durations of ICU and hospital stay in the primary LDLT group and pre-Kasai group were 180.4 vs 157.7 hours(P=0.18) and 27 vs 29 days(P=0.29),***:Primary LDLT is a safe and efficient management for young pediatric patients with *** with the outcome of LDLT for patients receiving a previous Kasai operation,a similar survival rate and a low rate of re-operation and intensive medical care for patients with BA can be obtained.

关键词： biliary atresia living donor liver transplantation pediatric Kasai operation

Crystal and molecular structure of main adduct of benzaldoxime dehydrodimer and styrene

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Chinese Journal of Chemistry 1991年第5期9卷 467-473页

作者： HU Hong-Wen WEI Xu-Dong li cun SUN Hong-Zhe YAO Yi-Ming ZHOU Zhong-Yuan YU Kai-Bei Department of Chemistry Nanjing UniversityNanjing 210008 Chengdu Center of Analysis and Measurment Academia SinicaChengdu 610005

Three 1:1 adducts have been obtained by heating benzaldoxime dehydrodimer with styrene. The main product possesses the structure of bis-nitrone type. A radical addition mechanism is pro- posed.

关键词： Crystal and molecular structure of main adduct of benzaldoxime dehydrodimer and styrene

Clinical and pathologic features of a distal myopathy family

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Clinical and pathologic features of a distal myopathy family

不确定理论下带惩罚机制的城市污水处理期望收益模型

生命的分子机器及其调控网络——2012年全国生物化学与分子生物学学术大会

作者： Mei-ling Wang cun-bao li Inner Mongolia Medical University

Objective To report the clinical manifestations and pathological features in a Chinese family with distal *** Family survey,genetic map,Clinical mani-festation and pathological features of biopsied muscle specimens were summarized and analysed, We could make the primary *** The onset of disease in the proband was a 29 years old *** the age of 13 he appeared clubfoot,progressive mus-cular atrophy and weakness in the lower *** studied five generations which have 117

关键词： Distal myopathy A family study Miyoshi myopathy Clinical and pathology

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中国环境科学 2018年第7期38卷 2794-2800页

作者：张林李存林李丹北方民族大学数学与信息科学学院宁夏银川750021 北方民族大学管理学院宁夏银川750021

为了防止政府与污水处理企业在委托代理关系中的"道德风险",在引入惩罚机制背景下,构建了不确定期望收益模型,以解决城市污水处理问题.基于不确定理论,将模型转化为非线性约束规划,进一步证明了模型可行解的存在性.结合数值算例,对模型... 详细信息

为了防止政府与污水处理企业在委托代理关系中的"道德风险",在引入惩罚机制背景下,构建了不确定期望收益模型,以解决城市污水处理问题.基于不确定理论,将模型转化为非线性约束规划,进一步证明了模型可行解的存在性.结合数值算例,对模型进行验证.用控制变量方法,通过对不确定指数、惩罚率、无风险处理量的分析,得出企业签约量与收益、风险成正比,惩罚率与企业签约量、收益成反比,企业无风险处理量与企业签约量、收益成正比.可见,引入惩罚机制能够有效防止企业投机行为,并对降低企业"道德风险"具有显著作用.

关键词：城市污水处理期望收益不确定理论惩罚机制

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惠州城市的形成与发展

地理科学 1999年第2期19卷 176-180页

作者：李存广东惠州大学地理系

从历史地理的角度研究惠州城市的形成和发展，重点考察了腹地和职能的演化。基于动力学分析，认为惠州城市未来发展的动力将主要来自石化、电子等行业的工业化和以惠州港为中心的交通枢纽地位。

关键词：惠州市城市形成城市发展腹地演化