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Partial sine wave tracking dual mode control topology for a single-phase transformerless photovoltaic system

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Journal of Modern Power Systems and Clean Energy 2018年第6期6卷 1338-1343页

作者： Koki OGURA Mohan Lal KOLHE Mutsuo NAKAOKA Kyushu Sangyo University University of Agder University of Malaya

A unique high efficiency photovoltaic(PV)system is presented. It uses partial sine wave tracking for a pulse-width modulation(PWM) boost converter as well as a full-bridge inverter. The boost converter and full-bridge inverter are connected via a compact intermediate film capacitor(i.e. non-smoothing DC link stage). PWM switching is activated by a dual mode control technique. In the proposed topology, simultaneous switching of both power conversion stages is avoided and therefore this increases the power conversion efficiency. The distinctive operating principles of these two power processing stages are discussed and analyzed with the experimental results for single-phase loading of the PV system.

关键词： Partial sine wave instantaneous tracking pulsewidth modulation(PWM) boost converter Bypass diode Dual mode control High efficiency power conversion

NEW THREE PHASE VFVA sine WAVE GENERATOR AND PWM HARMONICS ANALYSIS

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Journal of Electronics(China) 1994年第1期11卷 79-87页

作者：林棋 Fuzhou University Fuzhou 350002

The new three phase VFVA sine wave generator is presented in this paper. A new sampling holding three phase VFVA sine wave generator’s principle, circuit and experimentation waveform are introduced. The principle of this sampling holding circuit is simple and the realization of har’dware circuit is easy. Here we describe the three phase reference sine wave which is produced by this generator’s circuit and is required by PWM inverter is described in this paper, and also introduced the speed control and harmonir analysis of PWM inverter variable frequency.

关键词： sine wave generator Harmonics analysis Three phase VFVA

sine TRANSFORM PRECONDITIONERS FOR SECOND-ORDER PARTIAL DIFFERENTIAL EQUATIONS

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Numerical Mathematics A Journal of Chinese Universities(English Series) 1993年第1期2卷 116-123页

作者：金小庆 Faculty of Science and Technology University of Macao Macao.

In this paper, we are concerned with the numerical solution of second-order partial differential equations. We analyse the use of the sine Transform precondilioners for the solution of linear systems arising from the discretization of p.d.e. via the preconditioned conjugate gradient method. For the second-order partial differential equations with Dirichlel boundary conditions, we prove that the condition number of the preconditioned system is O(1) while the condition number of the original system is O(m 2) Here m is the number of interior gridpoints in each direction. Such condition number produces a linear convergence rale.

关键词： sine Transform finite difference method second-order partial differential equation condition number preconditioned conjugate gradient method

THE sine TRANSFORM OPERATOR IN THE BANACH SPACE OF SYMMETRIC MATRICES AND ITS APPLICATION IN IMAGE RESTORATION

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Numerical Mathematics A Journal of Chinese Universities(English Series) 1999年第2期8卷 231-242页

作者：高洁欣金小庆冼伟光

In this paper, we study an operator s which maps every n-by-n symmetric matrix A, to a matrix s(A_n) that minimizes || B_n-A_n || F over the set of all matrices B_n, that can be diagonalized by the sine transform. The matrix s(A_n), called the optimal sine transform preconditioner, is defined for any n-by-n symmetric matrices A_n. The cost of constructing s(A_n) is the same as that of optimal circulant preconditioner c(A_n) which is defined in [8], The s(A_n) has been proved in [6] to be a good preconditioner in solving symmetric Toeplitz systems with the preconditioned conjugate gradient (PCG) method. In this paper, we discuss the algebraic and geometric properties of the operator s, and compute its operator norms in Banach spaces of symmetric matrices. Some numerical tests and an application in image restoration are also given.

关键词： Toeplitz matrix optimal sine transform preconditioner since transform operator PCG method image restoration.

Logarithmic sine and Cosine Transforms and Their Applications to Boundary-Value Problems Connected with Sectionally-Harmonic Functions

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Applied Mathematics 2013年第2期4卷 378-386页

作者： Mithat Idemen Engineering Faculty OKAN University Istanbul Turkey

Let stand for the polar coordinates in R2, ?be a given constant while satisfies the Laplace equation in the wedge-shaped domain or . Here αj(j = 1,2,...,n + 1) denote certain angles such that αj αj(j = 1,2,...,n + 1). It is known that if r = a satisfies homogeneous boundary conditions on all boundary lines ?in addition to non-homogeneous ones on the circular boundary , then an explicit expression of in terms of eigen-functions can be found through the classical method of separation of variables. But when the boundary?condition given on the circular boundary r = a is homogeneous, it is not possible to define a discrete set of eigen-functions. In this paper one shows that if the homogeneous condition in question is of the Dirichlet (or Neumann) type, then the logarithmic sine transform (or logarithmic cosine transform) defined by (or ) may be effective in solving the problem. The inverses of these transformations are expressed through the same kernels on or . Some properties of these transforms are also given in four theorems. An illustrative example, connected with the heat transfer in a two-part wedge domain, shows their effectiveness in getting exact solution. In the example in question the lateral boundaries are assumed to be non-conducting, which are expressed through Neumann type boundary conditions. The application of the method gives also the necessary condition for the solvability of the problem (the already known existence condition!). This kind of problems arise in various domain of applications such as electrostatics, magneto-statics, hydrostatics, heat transfer, mass transfer, acoustics, elasticity, etc.

关键词： Integral Transforms Harmonic Functions Wedge Problems Boundary-Value Problems Logarithmic sine Transform Logarithmic Cosine Transform

HEXIM1蛋白与Alu sine RNA相互作用的研究

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四川大学学报（自然科学版） 2014年第4期51卷 842-846页

作者：田平平吴传芳欧阳劲秦岭四川大学生命科学学院成都610064 成都南诺格生物科技有限责任公司成都610064 成都华高瑞甜科技有限公司成都610064

为了探讨Alu sine RNA和HEXIM1蛋白之间是否存在相互作用.本实验构建了带有FLAG标签的HEXIM1真核表达载体,转染人胚肾293(HEK293)细胞,做anti-FLAG的RNA免疫共沉淀(RIP)后运用免疫印记和逆转录PCR(reverse transcription PCR,RTPCR)等方法检测.证明了Alu sine RNA和HEXIM1蛋白之间存在相互作用,表明Alu sine RNA和HEXIM1蛋白共同影响基因转录调控,以及细胞在应对外界刺激时能及时在基因水平做出有效反应的可能.

关键词： Alu sine RNA HEXIM1 免疫印迹半定量逆转录PCR 基因转录调控

应用促卵泡激素基因sine标记测定大约克猪纯合度

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贵州农业科学 2010年第5期38卷 140-142页

作者：李升赵星艳张兆强王三铭王嘉福冉雪琴贵州大学生命科学学院贵州贵阳550025 贵州大学农业生物工程省重点实验室贵州贵阳550025 贵州大学动物科学学院贵州贵阳550025

为了使猪种引进有便捷、准确的检测手段,采用聚合酶链式反应(Polymerase chain reaction,PCR)方法,检测了120头大约克种猪的纯合度。结果表明:受检母猪FSHβ基因的BB纯合基因型频率为82.5%,AB杂合基因型频率为17.5%,未检测到AA纯合基因... 详细信息

为了使猪种引进有便捷、准确的检测手段,采用聚合酶链式反应(Polymerase chain reaction,PCR)方法,检测了120头大约克种猪的纯合度。结果表明:受检母猪FSHβ基因的BB纯合基因型频率为82.5%,AB杂合基因型频率为17.5%,未检测到AA纯合基因型,经计算B等位基因的频率明显高于A等位基因频率。表明,该批次大约克猪存在一定比例的内二元或内三元杂交猪,应加强管理,严格控制再引种的纯度。该检测方法适用于区分国内地方猪品种和欧洲猪品种的纯合度,为引种种猪的纯合度检测提供准确的鉴定手段,有良好的应用前景。

关键词：大约克猪 FSHβ基因分子标记 sine

基于sine-RIPs标记的苏姜猪群体结构和遗传多样性分析

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中国畜牧杂志 2023年第2期59卷 147-154页

作者：迟诚林倪黎纲陶勇陈才周春宝宋成义王宵燕扬州大学动物科学与技术学院江苏扬州225009 江苏农牧科技职业学院江苏泰州225300

为了探究苏姜猪群体遗传结构与遗传多样性,本研究采用36个sine-RIPs(sine Retrotransposon Insertion Polymorphisms)标记检测苏姜猪育种核心群体的基因多态性,并分析群体的遗传参数,构建UPGMA(Unweightedpair Group Method Arithmeticmean)系统发育树。结果发现,苏姜猪群体中存在29个sine-RIPs多态性,UPGMA系统发育树将苏姜猪群体分为10个家系,家系的PIC范围为0.1883~0.2371,Fst的范围为0.011 7~0.299 1,Fis的范围为-0.902 0~-0.049 3,说明苏姜猪群体存在丰富的遗传多样性,群体近交程度较低。该研究结果为苏姜猪的持续选育和开发利用提供参考依据。

关键词：反转录转座子插入多态苏姜猪 sine 群体结构

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猪sine逆转座子进化分析及遗传效应探究

猪SINE逆转座子进化分析及遗传效应探究

作者：王梦礼扬州大学

学位级别：硕士

国内外的育种实践证明,基因组选择为主的分子育种技术可以显著提高猪育种效率和生产性能水平。在猪的基因组中,逆转录转座子插入多态(Retrotransposon insertion polymorphism,RIP)是导致结构变异的重要原因。利用基于RIP开发的分子标记... 详细信息

国内外的育种实践证明,基因组选择为主的分子育种技术可以显著提高猪育种效率和生产性能水平。在猪的基因组中,逆转录转座子插入多态(Retrotransposon insertion polymorphism,RIP)是导致结构变异的重要原因。利用基于RIP开发的分子标记,可以实现遗传效率高、通量大、重复性好、共显性等优点。因此,在QTL基因组选择、精细定位、遗传进化分析等研究中具有很好的应用前景。早期的研究表明,有大量的sine-RIPs存在于蛋白编码基因外显子区的3’UTR区,影响基因转录本结构及基因表达。基于这一发现,本研究在前期研究基础上进一步展开工作,得到以下结果:1、大量的sine分布密集,形成了大量的紧密串联情况。分析发现,在sine之间有连续出现现象的情况下,在5个碱基内筛选产生了约1.7万个串联位点。经过分析和统计,共获得26种串联类型,其中主要为两个年轻sine之间的串联,且多数为同向串联。2、在 10 个品种中对 ZNF7、SPATA6、SPATA17、PLA2G16、ZNF2、SLCO5A1、TAF4B、LPP和FGL1这9个基因对应的sine-RIPs位点进行PCR检测后均出现了多态,并且在所检群体中,有一半以上群体符合Hardy-Weinberg平衡;进一步在551个个体的大白猪群体中进行生长性能关联分析,发现ESA3-2位点的sine-/-个体的校正背膘厚显著大于sine+/-和sine+/+个体的校正背膘厚(Psine+/+个体的三十公斤体重日龄显著大于sine+/-和sine-/-(Psine+/+和sine+/-基因型极显著(Psine-/-基因型个体;REF-14309位点所在的SLCO5A1基因在背最长肌组织中sine+/+和sine+/-基因型个体中的表达量显著(Psine-/-基因型个体。在米猪中,REF-11172位点所在的PLA2G16基因在背膘中的表达水平sine+/+和sine+/-基因型分别极显著(Psine-/-基因型个体;相反的是,在肝脏中的表达水平sine+/+和sine+/-基因型分别极显著(Psine-/-基因型个体;REF-9759位点所在的FGL1基因在肝脏中的表达水平sine+/+显著(Psine-/-基因型个体。

关键词：猪转座子 sine 插入多态性关联分析