工作分析

In this article,the authors analyze the aiguille voltage of the whole-bridge DC source converter circuit according to the mathematics model when the MOSFET transistor is shut and the instant voltage equations are obtained.

对直流电源变换器的常用电路型式进行了具体工作过程分析；根据所建立的数学模型，分析MOS管关断瞬间的尖峰电压，得出其瞬间电压方程，并应用PSPICE软件的仿真结果对其进行验

This thesis contributed to the comprehensive study of the Finite-Difference Time-Domain method and its application to the numerical computation of radiated electromagnetic fields in switched mode power supplies. The work includes mainly three parts: the study on the performance of PML absorbing boundary condition applied to pseudo low frequency electromagnetic problems; the validation of the FDTD method with PML absorbing boundary conditions and the corresponding computer software based on the numerical study of the electromagnetic field of an electric dipole antenna, and its application to the numerical computation of radiated electromagnetic fields in switched mode power supplies; the development of an improved alternating direction implicit finite-difference time-domain method.

在综合前人工作基础上，本文对时域有限差分法及其在开关电源辐射电磁场数值计算中的应用进行了系统的分析和研究，其核心内容包括：伪低频电磁场数值计算中PML吸收边界条件性能的研究；基于基准问题—电偶极子天线三维辐射电磁场，验证了本文构造的基于PML吸收边界条件的三维FDTD法及其计算软件，并应用于高频开关电源辐射电磁场的数值分析；提出了一种改进的交替方向隐格式时域有限差分法。

The contents of trace elements of Ag, Cu, Zn, Fe, Pb, Sb and Bi in gold foil were determined directly by ICP-AES method and the gold content of gold foil was calculated. The authors obtained optimal working parameters of the instrument and studied the selections of power in analytic conditions and analytic curve, the optimization of the pressure of nebulizer as well as the influence of lifting capacity of the sample.

摘 要：研究了ICP-AES法直接测定金箔中的Ag、Cu、Zn、Fe、Pb、Sb、Bi微量元素，通过差减法计算出金箔的含金量，确定了仪器最佳工作参数，研究了分析条件中功率的选取、分析线的选择、雾化器压力的优化、样品提升量的影响，并对金箔中Au基体可能存在的干扰等进行了探讨。

The main work and the originality points of this dissertation could be concluded as the following parts:(1) To analyze systematically the mathematical model of LES of air flow in great space, under the case of isothermal and non-isothermal, as well as the combined action of buoyancy and strain. Some basic problems are studied about the LES application into airflow simulation of great space, such as boundary conditions, spatial difference scheme and time advancing scheme, time step etc., which creates the basis for the LES application to indoor airflow simulation.(2) Both the instantaneous and time averaged flow field of great space with multiple jets under isothermal and non-isothermal cases are explored with large eddy simulation method, and also discussed the dynamic characteristics and the law of fluidflow in the great space.(3) Based on the results of LES of the great space and the Fanger thermal comfort indexes, it is brought forward the concept of the series of dynamic thermal comfort evaluating indexes, which could be divided into thermal comfort index with time averaged properties PD, PPD, PMV, thermal comfort index with instantaneous properties IPD, IPPD, IPMV, and time averaged thermal comfort indexes TAPD, TAPPD, TAPMV, and transient situations time averaged thermal comfort indexes TTAPD, TTAPPD, TTAPMV. The differences among them and the calculation methods are discussed, and the four kinds of indexes are calculated with the thermal comfort index PD as an example.(4) Based on the LES results it is discussed the hot air stratification phenomena in air-conditioned buildings in the case with air supply and return registers on the ceiling and the case on the sidewall. The fundamentals of the hot air stratification are studied and the relations of estimating hot air stratification are brought forward.(5) With the advanced apparatus such as hot wire film anemometer IFA300 and laser particle field anemoscope, corresponding model test and site measurements have been done, which are compared with the simulation results and LES is proved a very promising method in air flow simulation indoor.

本文主要工作既创新点体现在以下几个方面：(1)系统分析了等温、非等温和考虑剪切力与浮升力综合作用的高大空间大涡模拟数学模型，并研究了高大空间大涡模拟在室内气流仿真应用中的一些基本问题，如边界条件、空间离散格式和时间推进格式、时间步长选择等问题，为大涡模拟在室内气流计算中的广泛应用打下了基础；(2)首次用大涡模拟方法研究了高雷诺数下高大空间多射流在等温、非等温情况下的瞬时流场和时均流场分布，并探讨了多射流流场的动态特性和流动规律；(3)基于大涡模拟的动态仿真结果和Fanger的热舒适指标，首次系统地提出了动态热舒适评价指标体系的概念：即基于时间平均参数的热舒适指标PD、PPD、PMV；基于瞬时参数的瞬时热指标IPD、IPPD、IPMV；基于时间平均热舒适指标TAPD、TAPPD、TAPMV；以及沿行动迹线的时间平均热舒适指标TTAPD、TTAPPD、TTAPMV，并分析了四类热舒适指标的差异性和计算方法，还以PD值为例对四类指标分别进行了计算；(4)基于数十种工况下空调房间大涡模拟的结果，研究了空调建筑上送上回和侧送侧回两种情况下热分层现象，并探讨了热分层的基本规律，首次提出了避免热分层现象的判断公式；(5)在暖通空调领域，首次使用IFA300热线风速仪、激光粒子速度场仪等先进设备，完成了与大涡模拟相对应的模型试验，并把实测结果与仿真结果进行了对比，说明LES在室内气流仿真方面是一种很有前景的方法。

In this paper, CAD is used to carry out the analysis of the positive kinematics of 3R robot, the velocity and acceleration curve s are drawn and discussed and analyzed, and the robot machine working state is animatedly simulated.

采用计算机辅助设计对 3R机器人机构进行正向运动分析，绘制出速度、加速度曲线并对其进行分析和讨论，动画模拟机器人机构工作状

For the first time, it is revealed that the low frequency component of secondary arc current of series capacitor compensated transmission lines has great influence on extinguishing secondary arc and success ratio of singlephase reclosing.

3通过理论分析和仿真计算，讨论了串补装置对输电线路工频过电压、操作过电压和雷电过电压的影响，并对串补电容器组在以上过电压作用时的工作条件进行了计算分析。

In order to achieve the aim of this study, a survey was conducted via a self-designed questionnaire of 403 novice teachers who had no more than three years of teaching experience in 28 junior high schools in Hsinchu County. Adopting SPSS to analyze the data thus collected, this study performed such statistical analyses as arithmetic mean, standard difference, t-test, One-Way Analysis of Variance, Pearson's correlation etc to verify hypotheses.

为达研究目的，本研究采用问卷调查法，研究对象为新竹县境内二十入所公立国民中学，任教年资在三年以下之新手教师，共403名，并使用研究者自编之「国中新手教师工作经验感受问卷调查表」为调查工具，将所得资料运用社会科学统计套装软体进行算术平均数、标准差、t考验、单因子变异数分析、皮尔逊积差相关等统计分析以验证假设。

The reason the default produced is analyzed and a new latest available unscheduled channel with smallest void algorithm is presented. The performance of the two algorithms is simulated. The results show that in LAUC-SV algorithm the effective window of the packet loss versus unit delay time of fiber delay lines is expanded significantly and the packet loss ratio is decreased about 100.5. The algorithm complexity of the LAUC-SV is only increased arithmetically with LAUC. Both the algorithms can not support delay reservation protocol effectively.

分析了产生此缺陷的原因并提出了一种LAUC算法的改进算法LAUC-SV算法，采用仿真的方法分析比较了两种算法的性能，结果表明LAUC-SV算法比LAUC算法的丢包率下降100.5，且LAUC-SV算法下的丢包率关于光纤延时线单元延时时间的工作窗口与传统LAUC相比大大展宽，而前者的算法复杂度与后者相比仅呈算术增长，但两算法均不能有效支持延时预约协议。

Therefore, the chiru attracted a lot of attentions of the Chinese government, conservation scientists and other conservative organizations in the world.In the present study, 57 chiru individuals were sampled from Arjin Shan Nature Reserve in Xinjiang, Chang Tang Nature Reserve in Tibet and Kekexili Nature Reserve in Qinghai. The present study, based on the analyses of the chiru mitochondrial control region with MEGA, DnaSP and ARLEQUIN programs, investigated into the genetic diversity background, evolutionary history and population relationships and aimed to provide scientific basis for the protection of the chiru.

本研究以采集于新疆阿尔金山自然保护区、西藏羌塘自然保护区和青海可可西里自然保护区的57个藏羚羊个体为研究对象，应用MEGA、DnaSP和ARLEQUIN等分析软件对其线粒体DNA控制环区序列进行分析，以研究当前藏羚羊种群的遗传多样性背景，地理种群关系及其进化历史中种群变化情况，并为藏羚羊的保护工作提供科学依据。

This paper analyzed and researched the characteristics of Schmitt trigger, single-stable-state trigger and astable multivibrator constituted by 555 timer based on PSPICE. Against the phenomenon of astable multivibrator constituted by 555 timer has no oscillation in PSPICE, an effective analysis method was brought out for 555 timer circuit to simulate the actual oscillator.

作者在文中应用PSPICE对555定时器构成的施密特触发器、单稳态触发器和多谐振荡器的工作特性进行了仿真分析和研究，针对PSPICE中555定时器构成的多谐振荡器不起振的问题提出了模拟振荡电路的有效起振方法，对电子电路的分析与设计具有一定的参考意义。

And discuss some key point of integrated management system design, include hazard identification and risk assessment and risk control in the occupational health and safety management, the measure of satisfaction target of customer, the flawlessness of law system, the integration of the integrated management system and enterprise standardization system, unify lead institution and work orgnization, integreted internal audit and integrated management review.

同时，论述了一体化管理体系构建中的几个主要问题，包括职业健康安全管理中的危险源辨识、风险评价和风险控制、顾客满意度的科学监测、法律、法规体系的完善、一体化管理体系与企业标准化体系的有机结合、统一的领导机构和工作机构、一体化的内部审核和管理评审。

Deepwater Taranaki is investigated for its petroleum potential, using all available seismic data tied to shallow-water wells.

运用与浅水井相关的现有全部震波探测数据考察了深海区塔拉纳基盆地的油藏前景。