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A novel zero-voltage and zero-current resonant pole soft-switching inverter was proposed to achieve zero- voltage and zero-current switching simultaneously when main power devices turn-on and turn-off. Therefore, turn-on capacitive losses could be reduced for devices which the intrinsic capacitor value cannot be neglected. Additionally losses caused by the tail current can also be reduced, when IGBTs are used as main switches.

提出一种新型的零电压零电流谐振极型软开关逆变器，可以在主功率器件开通和关断时，同时实现零电压和零电流，因此对于内部电容不能忽略的器件，可减小容性开通损耗，当绝缘栅双极型晶体管(insulated gate bipolar transistor，IGBT)作为主功率器件时，也可减小拖尾电流引起的损耗。

The result shows that: with the expansion of teacher education space, the reform and development of Chinese teacher education is much closer or equal to that of the international teacher education. The transitional stage and education reform in China puts forward a new demand for P. E. talents. The innovation as to education object, specification and curriculum arrangement raised in P. E. Curriculum Arrangement for Chinese Universities with four-year Program published in 2003 meets such a demand, and narrows the gap of education development in high P. E. academy between China and foreign countries. P. E. teachers abroad are usually cultivated by comprehensive universities, the cultivating objectives are verified, and generalists adapted to social development are emphasized. Cultivating mode abroad are various, with "open-type" or "non-directional type" as the main mode, and 4-year program, 5-year program, and 3-year program serve as the main form of education system. Curriculum arrangement abroad stresses general education, with foundationalization, normalization, objectification, optionalization, miniaturization, internationalization and syntheticalization as its characteristics and it employs credit system. The close-typed cultivating mode of P. E. academies in China should be gradually transformed into open-type or multi-type, cultivating generalists instead of specialists, and further constructing a new one with several cultivating types co-existing. Orientation of P.E. teachers in China should follow standard principle, coordination principle, experience principle and resource principle. To improve P.E teacher education in China, the following measures can be taken: relevant laws and regulations should be made for orientation; P.E teachers" training organization should be encouraged to participate in orientation; extension and connotation of P.E. teacher education should be expanded; resources should be optimize; systematic P.E. teachers" orientations should be organized;"Life P.E. Teacher Qualification "should be changed; useful-life should be set for P. E. teacher qualification; P.E. teacher qualification should be regularly authenticated; On-job training of P. E. teachers abroad tends to be systematic, but in China P.E. teachers" on-job training and prevocational training are separated; therefore measures must be taken to change this circumstance and thus speed up the systematic process. Factors concerning constructing a new system of P. E teachers are the following: reconstructing resources, making P.E. teachers" cultivation, orientation and training systematic, establishing a mechanism for encouragement and punishment, making school-based training and college training systematic, and setting up a mechanism combining directional training with non-directional training.

研究结果表明：随着教师教育革新空间的拓展，我国体育教师教育的改革与发展水平逐步与国际体育教师教育发展趋于接轨化。2003年颁布的《全国普通高校体育教育本科专业课程方案》在培养目标和规格、课程设置上的创新性，适应了我国社会转型和教育改革对体育教育专业人才的需求，进一步缩小了与国外高等体育院系教育发展的差距；国外体育教师一般由综合性大学或文理多科性大学培养，培养目标多向化，以培养适应社会发展的通才型人才为主；培养模式灵活多样，多数以"开放型"或"非定向型"培养模式为主，学制多以4年制、5年制、3年为主；课程设置上注重通识教育，突出基础化、师范化、针对化、选修化、小型化、国际化和综合化特点，实行完全学分制的教育管理制度；我国普通高校体育教育本科专业人才培养模式应该由封闭性转向开放式混合型的人才培养模式转变，由专才型转向复合型人才培养模式转变，构建多种类型并存的人才培养模式；我国体育教师入职教育革新应遵循的原则是本位原则、协同原则、经验原则和时间与资源原则，改进措施有：做好入职教育的法规化、制度化建设，激励体育师资培育机构参与体育教师的入职教育，拓展体育教师教育的外延和内涵，优化整合资源，系统组织体育教师的入职教育，改变体育教师资格"终身制"，设定体育教师资格有效期限，推行教师资格定期认证制度等；国际上体育教师在职培训体系显现了体育教师教育一体化的发展取向，但我国体育教师的在职培训与职前培养存在分离性，必须采取改革措施，加速我国体育教师教育的一体化进程；构建体育教师教育新体系的实施要素是：重组资源配置，实现体育教师培养、入职和培训一体化，建立奖惩机制，实现校本与院校培训一体化，建立体育教师定向与非定向培养培训有机结合机制。

For color when you print the map out of the black and white, the main reason is the primary file that contains only the low solution puctatus gray, although the color when you print, but it is rough, the main reason is the primary file contains is a low resolution of the color figure.

差于不不不彩色打印时打不入暗白的图，其次给来因是主文件只包罗了矮不系象的灰度图，差于不不不彩色打印时虽然是彩图，但很粗劣，其次给来因是主文件包罗的是矮不系像的不不不彩色图。

The main achievements could be summarized as follows.1. The basic stress-strain characteristics and related physical mechanisms for sands under cyclic rotation of principal stress axes were investigated based on three kinds of drained tests including fixed principal stress axes, cyclic rotation of principal stress axes with magnitudes of principal stresses kept constant, and cyclic changes of principal stresses in both their axes and magnitudes. The main deformation behavior of sands with inherent anisotropy under cyclic rotation of principal stress axes with magnitudes of principal stresses kept constant was obtained in the following.

本文从试验研究、规律分析、数学建模和工程应用四个方面，对应力主轴循环旋转条件下砂土的变形特性进行了较为深入的研究，取得了如下主要研究成果：(1)基于对饱和砂土进行的主轴固定单调剪切、纯应力主轴循环旋转以及主应力幅值与应力主轴耦合循环变化的三类完全排水试验成果，分析和揭示了应力主轴循环旋转条件下砂土的基本变形规律，并探讨了其受力变形的内在机理。

This article that focuses on the systematic and in-depth research in the current primal problem about abnormal burst pressure reservoir depress burst pressure has procured following main fruits:1 It forms the method which could obtain massive vertical static state mechanics parameters.2 In a foundation of acquisition of rock mechanics parameters,apply bent lamella that as mechanical model along with characteristic of actual geologic characteristics to analysis curvature for anticlinal strcture, get homologous tectonic stress value throug relation between the curvature and stress and different principal curvature in anticlinal structure,consequently set up laminational stress model for anticline reservoir. The block lamination for existed fracturing date has formed method of setting up mechanical model of lamination terrestrial stress by abtaining the block tectonic stress coefficients which are got by complex utilization test, laboratory test and fracturing date playback.3 Analysesing the main reason which lead to high burst pressure by considering the characteristic of reservoir geology,reservoir,and rock mechanics and reservoir damage,etc.Establishing burst pressure quantitative prediction model which provide gist for depressing construction risk and optimizing construction craft under the condition of open hole completion ,gun-perforated completion and damaged reservoir.4 Provding theoretical basis for interpreting acidification pretreatment which could depress busrt pressure by finding the relation between the influencing factors and rock machanics parameters and analysing the factors that have effect on rock mechanics parameters. Expounding the mechanism of reaction of mixed monomineral and acid from the angle of microcosmic element, evaluating quantitatively acid sensilility of different kinds of mineral effectively, and determing the first-order reaction dynamical equation of each mineral.5 Revealing rock mechanics property chage as a result of acid flooding in different condition by sandstone traumata experiment in different temperatures which combined with rock mechanics triaxial stress experiment.6 Associating damage mechanics with sandstone acidizing, established sandstone damage mechanics model in the foundation of the recognition on the rock mechanics parametric variation which is caused by acid-rock reaction in both macroscopic view and microscopic view ,also demonstrated those processes and quantitative estimated the acid busrt pressure to direct the site operation.

本文针对目前异常破裂压力储层降低破裂压力的主要问题展开较为系统和深入的研究，取得了以下主要成果：1形成了利用测井资料，结合室内岩芯测试结果，获取静动岩石力学参数的相关性特征，从而获得纵向上大量静态力学参数的方法。2在获取了岩石力学参数的此基础上，利用弯曲薄板作为力学模型，结合区块实际地质特征对背斜构造进行曲率分析，通过曲率与应力的关系，利用背斜构造不同部位的主曲率求得相应的构造应力值，从而建立起背斜储层的分层应力模型；对已有压裂资料的区块分层，形成了综合利用测试、室内实验、压裂资料反演获得该区块构造应力系数，建立起分层地应力的力学模型的方法。3综合考虑储层地质、油藏、岩石力学特性和储层伤害等因素，分析造成高破裂压力的主要原因，综合利用岩石力学、弹性力学等知识，建立了裸眼完井、射孔完井条件下以及储层受到伤害后的储层破裂压力定量预测模型，为降低施工风险和优化施工工艺提供了依据。4完成了物性、岩性影响岩石力学参数的因素分析，找出了各影响因素和岩石力学参数之间的关系，为从机理上解释酸化预处理降低破裂压力提供了理论基础；从微观元素的角度阐述了单矿物与酸反应的机理；并在此基础上，有效评价了各种矿物的酸敏感性，定量确定了岩石中各矿物的一级反应动力学方程。5完成了不同温度下的酸液类型、酸液浓度、注酸量等一系列砂岩损伤实验，结合岩石力学三轴应力实验，系统揭示了在不同条件下注酸而引起的岩石力学性质变化。6将损伤力学与砂岩酸化相结合，在宏观、微观两个方面认识酸岩反应引起岩石力学参数变化基础上，建立了砂岩损伤力学模型，并对其进行验证，在此基础上定量计算酸化后的破裂压力，有效指导现场施工

It mainly produces cassette stereo high-speed duplicators. The main productions include three principal series: 5 times speed, 12 times speed,16 times speed. Following are the main productions: YS-01, 1 to 1 duplicator, YS-100: 1 to 100 duplicator; CCD-2101: 1 to 1 duplicator, CCD-2100: 1 to 100 duplicator.

公司主要生产盒式立体声高速磁带复录机，产品分为：10倍速、24倍速、32倍速三大系列；产品有：CCD-2101一复一磁带复录机--CCD-2100一复一百磁带复录机、YS-01一复一磁带复录机--YS-100一复一百等各款磁带复录机。

The value of the principal terms of always mean meaningful, but the main range is different, so the main value is likely due to the size and scope of showing a "Community" and "Si Yi" and the resulting in the social life of the value of sequence The distinction.

价值对主体而言总是意味着有意义，但主体的范围是不同的，因此价值就有可能因主体的范围大小而呈现出"公益"、"私益"以及由此而来的在社会生活中的价值序列上的区别。

In this topic, the dynamic analysis methods for piezoelectric vibrator are studied systematically based on the theoretical model, FEM numerical experimentation and FEM governing equation for given compound-mode vibrator, and some valuable conclusions are obtained. The main work accomplished is summarized as follows: 1.Elaborate the main modeling methods for piezoelectric vibrator and the significance and necessity to study the dynamic characteristics of piezoelectric vibrator which emphasize the urgency of this paper. 2.Take the bending deformation induced by piezoelectric ceramic as example, the energy transfer mechanism of electric energy to mechanical energy are analyzed; the motion and force transfer mechanism are analyzed for the longitudinal-bending vibrator. 3.Based on mode assumption and Hamilton principle, the coupling model of piezoelectric vibrator of linear USM is built; moreover, the equivalent circuit model is obtained and a coupling equation represents the relation between electric parameters and mechanical parameters is derived which provides foundation to match the vibrator and driving circuit. 4.Combine the constitutive equation of piezoelectric ceramic with elastic-dynamical equation, geometric equation in force field and the Maxwell equation in electric field and the corresponding boundary condition equation, the FEM control equation for piezoelectric vibrator of USM to solve dynamic electro-mechanical coupling field is established by employing the principle of virtual displacement. The equation lays the foundation to study the non-linear constitutive equation of piezoelectric ceramic driven by high-power. 5.Define the dynamic indexes of characteristic of vibrator and carry out variable parameters simulation by calculating the model parameters and the electric characteristics of vibrator are simulated according to the equivalent circuit model. By numerical experimentation, the working mode of vibration of vibrator and the shock excitation results of the working frequency band which provides the mode frequency to realize bimodal are analyzed. Detailed calculation of the electro-mechanical coupling field parameters is made by programming the FEM control equation.

本课题从理论模型、有限元数值试验、有限元控制模型等方面以复合振动模式振子为例对超声电机压电振子的动力学特性及其分析方法进行了全面系统地研究，得出了许多有价值的结论，主要概括如下： 1、阐述了目前针对超声电机压电振子的主要建模方法，对压电振子动态特性的研究意义和必要性进行了论述，突出了本文研究内容的迫切性； 2、以压电陶瓷诱发弹性体发生弯曲变形为例，分析了压电陶瓷通过诱发应变来实现机电能量转换的机理；对基于纵弯模式的压电振子的运动及动力传递机理进行了分析； 3、基于模态假定，利用分析动力学的Hamilton原理，建立了面向直线超声电机压电振子的机电耦合动力学模型，并据此建立了压电振子的等效电路模型，导出了电参量与动力学特性参量的耦合方程，为压电振子与驱动电路的匹配提供了依据； 4、从压电陶瓷的本构方程出发，综合力场的弹性动力学方程、几何方程、电场的麦克斯韦方程以及相应的边界条件方程，采用虚位移原理，建立了压电振子动态问题机电耦合场求解的有限元控制方程，为研究其大功率驱动下的非线性本构模型奠定了基础； 5、界定压电振子的动力学特性指标，对压电振子的机电耦合动力学模型参数进行计算及变参数仿真；依据等效电路模型，对压电振子的电学特性进行了仿真分析；通过有限元数值实验，对压电振子工作模态附近的模态振型及工作频率附近的频段进行了激振效果分析，找出了实现模态简并的激振频率；利用有限元控制方程，通过编程计算，对压电振子的力电耦合场参数进行了详细计算，得出了一些有价值的结论。

The prodrome of this paper includes main topics, research purpose, researching range and current situation about the relevant research in China and abroad, and the main methods the paper adopted.

在论文的序论中，介绍了论文的主题和研究目的，论文的研究范围，国内外相关领域的研究现状，以及论文研究采用的主要研究方式。

According to the learning of the Power l Supplying Projet, the primary design is about the 10kv switch-substation, according to the load and demand of the supply electric system of factory, the design of the gather reduction voltage substation and distribution system, and the checking of the main electric apparatus, the protection and adjusting and the lightning protection of the main voltage changer and line.

本文通过对供电工程的学习，主要是针对10kV开闭所进行初步设计。根据所提供的负荷及对供配电系统的要求，对主要设备进行选型校验，对主变压器、线路进行保护整定计算，对主、变线路进行防雷保护等。

Putt your way through 36 fun-filled holes of minigolf on 3D designed courses with elevated greens, bunkers, bridges and water hazards, among other crazy obstacles.

您的推杆方式，通过36个有趣的填孔迷你的三维设计的课程，以提升绿党，掩体，桥梁和水的危害，除其他疯狂的障碍。

Some participles can be used either as attributes or as predicatives.

有些分词既可当定语用，也可当表语用。