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用磁阵列传感器去偏心误差的非接触式电流测量方法
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作者 吴远密 许守东 +2 位作者 姜孟 张文斌 程康 《传感器与微系统》 CSCD 北大核心 2024年第6期133-136,共4页
磁性传感器圆形阵列是电流非接触式测量的有效方法,因为它成本低、重量轻、线性范围大、带宽宽和噪声低。针对现有阵列式电流传感器测量偏心时存在较大电流测量误差的问题,采用一种基于导线偏心位置的区域层次分析方法。通过对载流导线... 磁性传感器圆形阵列是电流非接触式测量的有效方法,因为它成本低、重量轻、线性范围大、带宽宽和噪声低。针对现有阵列式电流传感器测量偏心时存在较大电流测量误差的问题,采用一种基于导线偏心位置的区域层次分析方法。通过对载流导线不同偏心位置,赋予磁传感器不同的权重进行输出叠加,与导线中心位置输出进行对比,求得最大相对误差为1.28%,传感器线性误差为1.04%,克服了导线偏心对电流测量误差的影响,证明了该方法的可行性。 展开更多
关键词 圆形阵列 电流测量 非中心 磁通门传感器 非接触式
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The Series of Reciprocals of Non-central Binomial Coefficients 被引量:5
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作者 Laiping Zhang Wanhui Ji 《American Journal of Computational Mathematics》 2013年第3期31-37,共7页
Utilizing Gamma-Beta function, we can build one series involving reciprocal of non-central binomial coefficients, then We can structure several new series of reciprocals of non-central binomial coefficients by item sp... Utilizing Gamma-Beta function, we can build one series involving reciprocal of non-central binomial coefficients, then We can structure several new series of reciprocals of non-central binomial coefficients by item splitting, these new created denominator of series contain 1 to 4 odd factors of binomial coefficients. As the result of splitting items, some identities of series of numbers values of reciprocals of binomial coefficients are given. The method of splitting terms offered in this paper is a new combinatorial analysis way and elementary method to create new series. 展开更多
关键词 BINOMIAL Coefficients Split Terms Reciprocals SERIES non-central Closed Form
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An Extension of the Non-central Wishart Distribution with Integer Shape Vector
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作者 Kaouthar KAMMOUN 《Acta Mathematica Sinica,English Series》 SCIE CSCD 2024年第9期2153-2168,共16页
This research paper deals with an extension of the non-central Wishart introduced in 1944 by Anderson and Girshick,that is the non-central Riesz distribution when the scale parameter is derived from a discrete vector.... This research paper deals with an extension of the non-central Wishart introduced in 1944 by Anderson and Girshick,that is the non-central Riesz distribution when the scale parameter is derived from a discrete vector.It is related to the matrix of normal samples with monotonous missing data.We characterize this distribution by means of its Laplace transform and we give an algorithm for generating it.Then we investigate,based on the method of the moment,the estimation of the parameters of the proposed model.The performance of the proposed estimators is evaluated by a numerical study. 展开更多
关键词 Cholesky decomposition Laplace transform method of moments non-central Wishart distribution Riesz distribution
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Spatial distributions of magnetic field in the RHIC and LHC energy regions 被引量:4
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作者 钟洋 杨纯斌 +1 位作者 蔡勖 冯笙琴 《Chinese Physics C》 SCIE CAS CSCD 2015年第10期61-67,共7页
Relativistic heavy-ion collisions can produce extremely strong magnetic fields in the collision regions. The spatial variation features of the magnetic fields are analyzed in detail for non-central Pb Pb collisions at... Relativistic heavy-ion collisions can produce extremely strong magnetic fields in the collision regions. The spatial variation features of the magnetic fields are analyzed in detail for non-central Pb Pb collisions at LHC at √SNN= 900, 2760 and 7000 GeV and Au-Au collisions at RHIC at √SNN=62.4, 130 and 200 GeV. The dependencies of magnetic field on proper time, collision energies and impact parameters are investigated in this paper. It is shown that an enormous and highly inhomogeneous spatial distribution magnetic field can indeed be created in off-centre relativistic heavy-ion collisions in RHIC and LHC energy regions. The enormous magnetic field is produced just after the collision, and the magnitude of magnetic field of the LHC energy region is larger than that of the RHIC energy region at small proper time. It is found that the magnetic field in the LHC energy region decreases more quickly with the increase of proper time than that of the RHIC energy region. 展开更多
关键词 the distribution of magnetic field non-central collision
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音像文献学学科建设与电影研究:以《微影片中的大历史——“学甲上白礁”祭典》为例
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作者 井迎瑞 《戏剧与影视评论》 2023年第6期64-75,共12页
音像文献学为电影研究领域提供了新的视角,以物质性、劳动性、在地视角与历史唯物主义史观为核心要旨,强调电影作为文化遗产的物质属性和保存的必要性。该学科的研究内容不仅包括官方或主流文献,也广泛涵盖民间、地方和社区的历史记录,... 音像文献学为电影研究领域提供了新的视角,以物质性、劳动性、在地视角与历史唯物主义史观为核心要旨,强调电影作为文化遗产的物质属性和保存的必要性。该学科的研究内容不仅包括官方或主流文献,也广泛涵盖民间、地方和社区的历史记录,旨在实现对历史的全面理解。对《学甲慈济宫上白礁祭典》相关影像的修复与保存作为典型案例,展现了音像文献在记录和保存非物质文化遗产中的关键角色,并探讨了如何通过音像文献构建集体记忆并促进文化传承。 展开更多
关键词 媒体考古学 媒介 非中心 集体记忆 媒体素养
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Determine the Eigen Function of Schrodinger Equation with Non-Central Potential by Using NU Method
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作者 Hamdollah Salehi 《Applied Mathematics》 2011年第8期999-1004,共6页
So far, Schrodinger equation with central potential has been solved in different methods but solving this equation with non-central potentials is less dealt with. Solving such equations are way more difficult and comp... So far, Schrodinger equation with central potential has been solved in different methods but solving this equation with non-central potentials is less dealt with. Solving such equations are way more difficult and complicated and a certain and limited number of non-central potentials can be solved. In this paper, we introduce one of the solvable kinds of such potentials and we will use NU method for solving Schrodinger equation and then by using this method we have calculated particular figures of its energy and function. 展开更多
关键词 SCHRODINGER Equation(SE) non-central POTENTIALS NU METHOD central Potential
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基于自组织网络的无中心指挥调度系统研究 被引量:2
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作者 侯荣涛 《数字通信世界》 2018年第4期20-21,27,共3页
传统4层结构的通信网络因为存在中心网络,已无法满足专网指挥调度系统机动、快速、灵活的部署要求,本文提出无中心指挥调度通信系统,采用传输层基于自组织网络,通信层去中心化,全网基于全IP体系结构,设计了系统软、硬件,实现了呼叫方法... 传统4层结构的通信网络因为存在中心网络,已无法满足专网指挥调度系统机动、快速、灵活的部署要求,本文提出无中心指挥调度通信系统,采用传输层基于自组织网络,通信层去中心化,全网基于全IP体系结构,设计了系统软、硬件,实现了呼叫方法,可用于公安、部队、武警、消防等紧急部署和快速组网的行业需求。 展开更多
关键词 自组织网络 无中心指挥调度系统 全IP体系结构 呼叫方法
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Implementing an Optimal Energy Management System for a Set of Microgrids Using the Harmony Search Algorithm
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作者 Xiangjian Shi Teng Liu +1 位作者 WeiMu Jianfeng Zhao 《Energy Engineering》 EI 2022年第5期1843-1860,共18页
A microgrid(MG)refers to a set of loads,generation resources and energy storage systems acting as a controllable load or a generator to supply power and heating to a local area.The MG-generated power management is a c... A microgrid(MG)refers to a set of loads,generation resources and energy storage systems acting as a controllable load or a generator to supply power and heating to a local area.The MG-generated power management is a central topic for MG design and operation.The existence of dispersed generation(DG)resources has faced MG management with new issues.Depending on the level of exchanges between an MG and the main grid,the MG operation states can be divided into independent or grid-connected ones.Energy management in MGs aims to supply power at the lowest cost for optimal load response.This study examines MG energy management in two operational modes of islanded and grid-connected,and proposes a structure with two control layers(primary and secondary)for energy management.At the principal level of control,the energy management system is determined individually for all MG by taking into consideration the probability constraints and RES uncertainty by the Weibull the probability density function(PDF),generation resources’power as well as the generation surplus and deficit of each MG.Then,the information of the power surplus and deficit of each MG must be sent to the central energy management system.To confirm the proposed structure,a case system with two MGs and a condensive load is simulated by using a multi-time harmony search algorithm.Several scenarios are applied to evaluate the performance of this algorithm.The findings clearly show the effectiveness of the proposed system in the energy management of several MGs,leading to the optimal performance of the resources per MG.Moreover,the proposed control scheme properly controls the MG and grid’s performance in their interactions and offers a high level of robustness,stable behavior under different conditions and high quality of power supply. 展开更多
关键词 Harmony search algorithm multi-MG system multi-owner systems central and non-central control optimal energy management uncertainty
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Analysis of the Probability Model of Wind Load on the Offshore Wind Turbine
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作者 Bowen Jiang Mingjie Zhao +1 位作者 Pan Liu Ziyuan Tang 《Open Journal of Civil Engineering》 2015年第2期261-267,共7页
According to the actual measurement data, probability models of horizontal wind load were obtained based on wind velocity statistic and power spectral density function of fluctuating wind velocity through stochastic s... According to the actual measurement data, probability models of horizontal wind load were obtained based on wind velocity statistic and power spectral density function of fluctuating wind velocity through stochastic sampling and using spectrum analysis method. Through the comparison of two models, probability models of horizontal wind load based on probability models of fluctuating wind velocity were obtained by revising the mean and variance of fluctuating wind velocity. Results show that the variance takes lower value when the power spectral density function of fluctuating wind velocity is used to obtain the probability model of horizontal wind load. The quadratic term of fluctuating wind velocity takes a small contribution value in total wind load with almost no contribution to the model of horizontal wind load. It is convenient for practical engineering to obtain the models of horizontal wind load by using probability models of fluctuating wind velocity. 展开更多
关键词 The OFFSHORE WIND TURBINE Spectrum ANALYSIS non-central CHI-SQUARE Distribution PROBABILITY Density Function
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Asymptotic distributions of non-central studentized statistics
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作者 SHAO QiMan ZHANG RongMao 《Science China Mathematics》 SCIE 2009年第6期1262-1284,共23页
Let X 1, ..., X n be independent and identically distributed random variables and W n = W n (X 1, ..., X n ) be an estimator of parameter ?. Denote T n = (W n ? ? 0)/s n , where s n 2 is a variance estimator of W n . ... Let X 1, ..., X n be independent and identically distributed random variables and W n = W n (X 1, ..., X n ) be an estimator of parameter ?. Denote T n = (W n ? ? 0)/s n , where s n 2 is a variance estimator of W n . In this paper a general result on the limiting distributions of the non-central studentized statistic T n is given. Especially, when s n 2 is the jacknife estimate of variance, it is shown that the limit could be normal, a weighted χ 2 distribution, a stable distribution, or a mixture of normal and stable distribution. Applications to the power of the studentized U- and L- tests are also discussed. 展开更多
关键词 non-central studentized statistics studentized U-statistics studentized L-statistics limiting distributions power of tests 62E20 62F05 60F05
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Non-Central Zone 3D Sound Field Reproduction for Multichannel System
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作者 WANG Song ZHANG Cong +2 位作者 PENG Bo WANG Heng HU Ruimin 《Wuhan University Journal of Natural Sciences》 CAS CSCD 2017年第6期498-502,共5页
The 22.2 multichannel system and its simplified system with 10-channel and 8-channel have been proposed, which brings people 3 D listening experience. But these systems could only accurately reproduce sound field at a... The 22.2 multichannel system and its simplified system with 10-channel and 8-channel have been proposed, which brings people 3 D listening experience. But these systems could only accurately reproduce sound field at a central listening point which is called sweetspot. In order to solve this problem, this paper proposes a non-central zone sound field reproduction method PVMDZ(particle velocity matching between different zones) based on the physical property of sound. The proposed method matches the physical property of sound of non-central zone in reconstructed sound field with that of central zone in original sound field, so the reproduced non-central zone would produce the same listening experience as the central zone of the original system does. By experiments, we compare the performances of the proposed method with the traditional one, and the result proves that the sound field error of proposed method is reduced. 展开更多
关键词 non-central zone sound field reproduction multichannel system
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Zero-inflated non-central negative binomial distribution
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作者 TIAN Wei-zhong LIU Ting-ting YANG Yao-ting 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2022年第2期187-198,共12页
In this article, the zero-inflated non-central negative binomial(ZINNB) distribution is introduced. Some of its basic properties are obtained. In addition, we use the maximum likelihood estimation method to estimate t... In this article, the zero-inflated non-central negative binomial(ZINNB) distribution is introduced. Some of its basic properties are obtained. In addition, we use the maximum likelihood estimation method to estimate the parameters of the ZINNB distribution, and illustrate its application by fitting the actual data sets. 展开更多
关键词 zero-in ated non-central negative binomial distribution maximum likelihood estimation good-ness of fit
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Ranking Independent Variables in Linear Models
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作者 Deng-Yuan Huang Ren-Fen Lee 《Journal of Mathematics and System Science》 2013年第2期89-95,共7页
In this article, the true model of sizep is considered. The importance of the independent variables will be studied. The model by dropping independent variable one at a time is called a reduced model, and the size of ... In this article, the true model of sizep is considered. The importance of the independent variables will be studied. The model by dropping independent variable one at a time is called a reduced model, and the size of the model is p-1. The non-centrality quantity is employed to measure the strength of influence on the true model for the independent variable dropped. The larger influence is defined to be more important in the true model. In this article, the goal is ranking the importance of the independent variables to study the structure of the models. It is important in the practical application. The confidence interval approach is used to rank the degrees of the influence of the independent variables in linear models and achieve the goal. An illustrative example is given, and the modeling procedure is studied to check the assumptions step by step in this example to make sure the assumptions satisfied in the true model. As a result, the proposed method can be used efficiently. 展开更多
关键词 non-central F-distribution non-centrality confidence interval Bonfcrroni inequality.
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两静质量不同的相对论性粒子间的非对心弹性碰撞
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作者 陈丽丽 谢崇伟 《云南大学学报(自然科学版)》 CAS CSCD 北大核心 2014年第S2期139-141,共3页
从相对论的角度,探讨了2个粒子间的非对心弹性碰撞,就入射粒子与其静质量不同的静止靶粒子碰撞后,出射速度方向间的夹角变化进行了研究.结果表明:当入射粒子碰前相对论质量大于靶粒子碰后相对论质量,碰后两粒子的运动方向之间的夹角小于... 从相对论的角度,探讨了2个粒子间的非对心弹性碰撞,就入射粒子与其静质量不同的静止靶粒子碰撞后,出射速度方向间的夹角变化进行了研究.结果表明:当入射粒子碰前相对论质量大于靶粒子碰后相对论质量,碰后两粒子的运动方向之间的夹角小于π/2,反之,则大于π/2. 展开更多
关键词 狭义相对论 弹性碰撞 非对心
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Exact Solutions of the Morse-like Potential,Step-Up and Step-Down Operators via Laplace Transform Approach
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作者 Altug Arda Ramazan Sever 《Communications in Theoretical Physics》 SCIE CAS CSCD 2012年第7期27-30,共4页
We intend to realize the step-up and step-down operators of the potential V (x) = V1 e 2βx+V2 e βx. It is found that these operators satisfy the commutation relations for the SU(2) group. We find the eigenfunctions ... We intend to realize the step-up and step-down operators of the potential V (x) = V1 e 2βx+V2 e βx. It is found that these operators satisfy the commutation relations for the SU(2) group. We find the eigenfunctions and the eigenvalues of the potential by using the Laplace transform approach to study the Lie algebra satisfied the ladder operators of the potential under consideration. Our results are similar to the ones obtained for the Morse potential (β→β). 展开更多
关键词 exact solution laplace transform non-central potential Schrdinger equation
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哈金《等待》中生命的“延异”
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作者 贺银花 原一川 祁艳红 《保山学院学报》 2011年第3期56-59,共4页
美国华裔作家哈金作品《等待》揭示出生命的"延异"特质。采用法国哲学家德里达的"延异"符号,我们可以发现《等待》中主人公的"暧昧性"、"无归属感"和"非中心"化。
关键词 等待 延异 暧昧性 无归属感 非中心
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THE LIMITING DISTRIBUTIONS OF SOME SUBCLASSES OF THE GENERALIZED NON-CENTRAL t-DISTRIBUTION
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作者 方开泰 袁克海 《Acta Mathematicae Applicatae Sinica》 SCIE CSCD 1993年第1期71-81,共11页
A general theorem on the limiting distribution of the generalized t-distribution is obtained,many applications of this theorem to some subclasses of elliptically contoured distributions in cluding multivariate normal... A general theorem on the limiting distribution of the generalized t-distribution is obtained,many applications of this theorem to some subclasses of elliptically contoured distributions in cluding multivariate normal and multivariate t distributions are discussed.Further,their limiting distributions by density function are derived. 展开更多
关键词 exp THE LIMITING DISTRIBUTIONS OF SOME SUBCLASSES OF THE GENERALIZED non-central t-DISTRIBUTION
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沿海重要港口非中央投资项目的建设情况
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作者 王广民 陈芸芸 《世界海运》 2005年第6期21-23,共3页
在对2004年非中央投资港口项目调研的基础上,对投资项目进行深入分析,总结了近年来我国港口建设发展的特点,提出非中央投资港口建设中存在的问题,并对中央与港口建设单位建立信息交流机制的可行性进行了分析。
关键词 港口 非中央 投资项目 建设情况
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疯狂的数字化货币——比特币的性质与启示 被引量:44
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作者 吴洪 方引青 张莹 《北京邮电大学学报(社会科学版)》 2013年第3期46-50,共5页
新型数字化货币"比特币"具有匿名性、去中心化、总量固定、交易成本低、可自由兑换等特征,近期受到广泛关注和热捧的同时,还带来了投机严重、网络犯罪、价格巨幅波动、社会资源浪费等问题和风险。比特币的出现有其技术、经济... 新型数字化货币"比特币"具有匿名性、去中心化、总量固定、交易成本低、可自由兑换等特征,近期受到广泛关注和热捧的同时,还带来了投机严重、网络犯罪、价格巨幅波动、社会资源浪费等问题和风险。比特币的出现有其技术、经济、社会的原因,因而应当从研究、教育、治理各个角度关注比特币现象。 展开更多
关键词 比特币 去中心化 交易成本
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凶险型前置胎盘43例临床分析 被引量:20
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作者 朝葵 杨承东 赖馨丽 《中国妇幼保健》 CAS 北大核心 2013年第24期3932-3934,共3页
目的:探讨凶险型前置胎盘的临床特点,预防产后出血发生率,降低严重产后出血和子宫切除的风险,提高围生儿的存活率,降低孕产妇死亡率。方法:对43例凶险型前置胎盘中的中央型组与非中央型组孕产妇妊娠结局进行回顾性分析。结果:中央型组... 目的:探讨凶险型前置胎盘的临床特点,预防产后出血发生率,降低严重产后出血和子宫切除的风险,提高围生儿的存活率,降低孕产妇死亡率。方法:对43例凶险型前置胎盘中的中央型组与非中央型组孕产妇妊娠结局进行回顾性分析。结果:中央型组与非中央型组严重产后出血率、胎盘植入率、DIC发生率、子宫切除率比较差异有统计学意义(P<0.05),而两组围产儿结局差异无统计学意义(P>0.05)。结论:中央型凶险型前置胎盘比非中央型凶险型前置胎盘植入率高,更容易发生严重的产时出血。提前彩超预测、术前充分识别评估风险及产时有效控制出血是治疗的关键。防止DIC发生,减少子宫切除事件及瘢痕子宫的发生,严格掌握剖宫产指征,搞好计划生育,注重产检及营养指导,降低剖宫产率,控制社会因素瘢痕子宫的发生可预防凶险型前置胎盘发生。 展开更多
关键词 凶险型前置胎盘 中央型前置胎盘 非中央型前置胎盘 妊娠结局
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