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点价δ~v的改造及其对A_nB_m型过渡元素化合物Δ_fH_m的相关性研究 被引量:12
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作者 杨锋 颜肖慈 +4 位作者 罗明道 周培疆 颜承农 望天志 屈松生 《原子与分子物理学报》 CSCD 北大核心 1998年第1期110-114,共5页
定义了有效价电子数Z′i,引入了成键电子数mi,并对分子中原子点价δv重新定义为δi,用δv和δi构成的分子结构参数Xv和X对33个AnBm型过渡元素卤化物标准生成焓的相关性研究表明,相关系数分别为0.9099,0.... 定义了有效价电子数Z′i,引入了成键电子数mi,并对分子中原子点价δv重新定义为δi,用δv和δi构成的分子结构参数Xv和X对33个AnBm型过渡元素卤化物标准生成焓的相关性研究表明,相关系数分别为0.9099,0.9400。在δi中如用价电子数Zi代替Z′i,则相关系数仅为0.9235。 展开更多
关键词 点价 AnBm型化合物 过渡型 相关性 有效电子数
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农民期货合作社经营模式创新研究——基于“期货点价+基差”视角 被引量:4
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作者 高欣宇 余国新 《金融理论与实践》 北大核心 2015年第6期59-63,共5页
目前农民专业合作社利用期货市场的主要模式还停留在"套期保值+订单"模式,然而这种模式的价格波动风险仍然存在,同时也无法规避订单风险履约率低的弊端,因此在基差交易的基础上,提出"期货点价+基差"的创新模式,将... 目前农民专业合作社利用期货市场的主要模式还停留在"套期保值+订单"模式,然而这种模式的价格波动风险仍然存在,同时也无法规避订单风险履约率低的弊端,因此在基差交易的基础上,提出"期货点价+基差"的创新模式,将价格风险转化为较小的基差风险,并能够保证实现完全的套期保值,同时以建立代表农户的棉花期货合作社为例具体描述涉棉企业、农户和期货合作社三方的操作流程,以及该模式的效果评价,最后提出相关政策建议。 展开更多
关键词 农民专业合作社 创新模式 期货点价 基差交易
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点价模式下再生金属海关估价问题研究
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作者 王浩 于倜 《海关与经贸研究》 2016年第4期96-104,共9页
金融危机以来,随着国内外形势的变化,全球再生金属贸易也正在发生深刻变化,大部分再生金属国际贸易采用点价模式对货物进行定价来规避风险,这加大了海关的价格管理难度。文章从点价的概念与要素入手,分析比较再生金属点价与现货交易的异... 金融危机以来,随着国内外形势的变化,全球再生金属贸易也正在发生深刻变化,大部分再生金属国际贸易采用点价模式对货物进行定价来规避风险,这加大了海关的价格管理难度。文章从点价的概念与要素入手,分析比较再生金属点价与现货交易的异同,针对当前点价模式海关审价工作中的难点,从创新审价理念、完善法制建设、加大信息合作、整合执法力量、加强队伍建设五个方面围绕再生金属点价模式的审价工作进行了研究与探讨,并提出了相关对策与建议。 展开更多
关键词 再生金属 点价 海关估
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叠墅类住宅设计要点及难点分析
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作者 王晓娟 《工程技术研究》 2022年第14期176-178,共3页
叠墅是一种以跃层户型为主、舒适度较高的多层住宅,产品定位介于高层住宅和别墅类住宅之间。文章以叠墅类住宅为主要讨论对象,分析叠墅类住宅的特点及溢价卖点,并结合实际项目经验,探讨叠墅设计要点及难点,以供参考。
关键词 叠墅 设计要 设计难
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基于神经网络构建取代苯类化合物QSAR模型 被引量:5
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作者 高大文 王鹏 《哈尔滨工业大学学报》 EI CAS CSCD 北大核心 2005年第11期1496-1498,1518,共4页
在取代苯类化合物定量构效关系(QSAR)模型构建中,采用人工神经网络技术对所选点价自相关拓扑指数结构参数进行筛选,并对筛选过程中不同数量的输入结构参数所构建的ANN-QSAR模型的质量和预测能力进行了比较.研究结果显示,应用人工神经网... 在取代苯类化合物定量构效关系(QSAR)模型构建中,采用人工神经网络技术对所选点价自相关拓扑指数结构参数进行筛选,并对筛选过程中不同数量的输入结构参数所构建的ANN-QSAR模型的质量和预测能力进行了比较.研究结果显示,应用人工神经网络自身非线性特点对QSAR研究中结构参数筛选是可行的,使最初QSAR模型中24个结构参数减少为5个,而模型的质量和预测能力没有受到影响.该研究成果不仅大大加快了网络模型的运算速度,而且为深入探讨取代苯类化合物生物致毒机理奠定了基础. 展开更多
关键词 取代苯类化合物 QSAR 人工神经网络 点价自相关拓扑指数
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用基团连接性指数计算烷烃和烯烃的化学 被引量:1
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作者 宣爱国 陈亚琴 +2 位作者 陈茹刚 李伟 彭昌军 《武汉化工学院学报》 2004年第2期8-10,共3页
为了获得一个简单可靠、通用的化学火用计算模型 ,根据物质的结构、特征计算了烷烃和烯烃的化学火用 .将烷烃和烯烃按其结构分成 1 1种基团 ,并提出了基团点价的概念 .根据基团连接性指数提出了一个用于计算化学火用的数学模型 ,其形式... 为了获得一个简单可靠、通用的化学火用计算模型 ,根据物质的结构、特征计算了烷烃和烯烃的化学火用 .将烷烃和烯烃按其结构分成 1 1种基团 ,并提出了基团点价的概念 .根据基团连接性指数提出了一个用于计算化学火用的数学模型 ,其形式为 E0x.ch( k J/ mol) =1 681 .83 1 5 ( 1 Ψ) +80 7.9762 .计算结果表明 ,最大误差小于 0 .2 8%,平均误差不大于 0 .0 69%. 展开更多
关键词 化学YONG 基团点价 分子连接性指数 烷烃 烯烃
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Existence of Positive Solution for Superlinear Semipositone Singular Second-order m-point Boundary Value Problem 被引量:4
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作者 ZHANG Xing-qiu 《Chinese Quarterly Journal of Mathematics》 CSCD 2010年第1期151-158,共8页
By applying fixed point theorem, the existence of positive solution is considered for superlinear semipositone singular m-point boundary value problem -(Lφ)(x)=(p(x)φ′(x))′+q(x)φ(x) and ξi ∈ (0,... By applying fixed point theorem, the existence of positive solution is considered for superlinear semipositone singular m-point boundary value problem -(Lφ)(x)=(p(x)φ′(x))′+q(x)φ(x) and ξi ∈ (0,1)with 0〈ξ1〈ξ2……〈ξm-2〈1,αi ∈ R^+,f ∈C[(0,1)×R^+,R^+],f(x,φ) may be singular at x=0 and x=1,g(x):(0,1)→R is Lebesgue measurable, g may tend to negative infinity and have finitely many singularities. 展开更多
关键词 SEMIPOSITONE SUPERLINEAR singular m-point boundary value fixed point theo-rem positive solution
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Positive Solutions of Boundary Value Problems for Systems of Nonlinear Second-order Differential Equations 被引量:3
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作者 ZHENG Dong-mei LU Shi-ping 《Chinese Quarterly Journal of Mathematics》 CSCD 2011年第2期179-184,共6页
By using fixed-point index theory,we study boundary value problems for systems of nonlinear second-order differential equation,and a result on existence and multiplicity of positive solutions is obtained.
关键词 boundary value problems fixed-point index positive solution CONE
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The SCUSUM Estimation of Variance Change Point in Linear Process 被引量:1
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作者 ZHAO Wen-zhi XIA Zhi-ming 《Chinese Quarterly Journal of Mathematics》 CSCD 2011年第2期170-173,共4页
This paper considers the estimation problem of a variance change-point in linear process.Consistency of a SCUSUM type change-point estimator is proved and its rate of convergence is established.The mean-unknown case i... This paper considers the estimation problem of a variance change-point in linear process.Consistency of a SCUSUM type change-point estimator is proved and its rate of convergence is established.The mean-unknown case is also considered. 展开更多
关键词 variance change point linear process rate of convergence
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RADIOGRAPHIC MEASUREMENTS OF THEHEIGHTS OF VERTEBRAL BODIES INTHORACICANDLUMBARSPINE 被引量:2
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作者 戴力扬 《Chinese Medical Sciences Journal》 CAS CSCD 1996年第2期117-119,共3页
Radiographic measurements was performed on 124 normal adults for anterior, posterior and middle heights of the vertebral bodies in thoracic and lumbar spine. The normal ratios of vertebral height in one vertebral body... Radiographic measurements was performed on 124 normal adults for anterior, posterior and middle heights of the vertebral bodies in thoracic and lumbar spine. The normal ratios of vertebral height in one vertebral body and one with the adjacent bodies were presented. The method for measurement and its diagnostic value to osteoporotic vertebral fractures were discussed. 展开更多
关键词 OSTEOPOROSIS spinal fractures
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A Measure System of Zero Moment Point Using Wearable Inertial Sensors
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作者 Xianggang Zhang Hao Wang +3 位作者 Yuliang Shi Changjun Fu Huiqin Wang Guoyu Wang 《China Communications》 SCIE CSCD 2016年第5期16-27,共12页
Keeping balance is the premise of human walking. ZMP(zero moment point) is a point where total torque achieves balance. It is an important evaluation parameter of balance ability in walking, since it can be used to be... Keeping balance is the premise of human walking. ZMP(zero moment point) is a point where total torque achieves balance. It is an important evaluation parameter of balance ability in walking, since it can be used to better reflect the dynamic balance during walking. ZMP can be used in many applications, such as medical rehabilitation, disease diagnosis, treatment and etc. In this paper, wearable inertial sensors system based on MEMS is used to measure ZMP(zero moment point) during walking, which is cheap, convenient, and free from the restriction of lab. Our wearable ZMP measurement system consists of inertial measurement subsystem and PC real-time monitoring station. Inertial measurement subsystem includes 9-axis inertial sensing nodes, the body communication network and the central node. Inertial sensing nodes are mounted on different parts of the body to collect body posture information in real-time, and then the best estimation of current posture are obtained by Kalman filter. The data from sensors is aggregated to the central node through the CAN bus, and then ZMP is calculated. Finally, it can be showed in the PC monitoring station. Experiments prove the system can achieve real-time ZMP detection during walking. 展开更多
关键词 zero moment point body balance inertial measurement quaternion Kalman filter
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Experimental Evaluation of the Post-ultimate Strength Behavior of a Ship's Hull Girder in Waves 被引量:7
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作者 Kazuhiro Iijima Ryota Wada Masahiko Fujikubo 《Journal of Marine Science and Application》 2012年第1期34-43,共10页
Experimental investigations into the collapse behavior of a box-shape hull girder subjected to extreme wave-induced loads are presented.The experiment was performed using a scaled model in a tank.In the middle of the ... Experimental investigations into the collapse behavior of a box-shape hull girder subjected to extreme wave-induced loads are presented.The experiment was performed using a scaled model in a tank.In the middle of the scaled model,sacrificial specimens with circular pillar and trough shapes which respectively show different bending moment-displacement characteristics were mounted to compare the dynamic collapse characteristics of the hull girder in waves.The specimens were designed by using finite element(FE)-analysis.Prior to the tank tests,static four-point-bending tests were conducted to detect the load-carrying capacity of the hull girder.It was shown that the load-carrying capacity of a ship including reduction of the capacity after the ultimate strength can be reproduced experimentally by employing the trough type specimens.Tank tests using these specimens were performed under a focused wave in which the hull girder collapses under once and repetitive focused waves.It was shown from the multiple collapse tests that the increase rate of collapse becomes higher once the load-carrying capacity enters the reduction path while the increase rate is lower before reaching the ultimate strength. 展开更多
关键词 post-ultimate strength collapse behavior experimental evaluation load-carrying capacity hull girder
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Existence of Solutions for Generalized Sturm-Liouville m-point Boundary Value Problems in Banach Spaces
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作者 YANG Jing-bao WEI Zhong-li 《Chinese Quarterly Journal of Mathematics》 CSCD 2011年第2期265-269,共5页
By applying the fixed-point theorem of strict-set-contraction,this paper establishes the existence of one solution or one positive solution to the generalized Sturm-Liouville m-point boundary value problem in Banach s... By applying the fixed-point theorem of strict-set-contraction,this paper establishes the existence of one solution or one positive solution to the generalized Sturm-Liouville m-point boundary value problem in Banach spaces. 展开更多
关键词 Banach spaces fixed-point theorem of strict-set-contraction STURM-LIOUVILLE m-pointt boundary value problem positive solution
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