TSM系统之异步切换的功率控制实现过程

简单介绍了TSM系统的发展和"远近效应"对系统的影响,以及克服“远近效应”的主要方法--功控制,接着介绍了TSM系统的切换分类,然后以异步切换过程为例%着重介绍相关的功率控制的实现过程,包括开环功率的计算方法和闭环功率的实现机理3这对TSM系统的异步切换过程的深入了解和功率控制的实现过程的正确全面的认识,以及对TSM系统的终端协议软件之异步切换部分的软件实现都具有一定的指导和促进作用。     

WCDMA上行功率控制的研究

功率控制是WCDMA系统中的一项关键技术，本文将从上行内、外环功率控制等两个方面简要介绍了上行功率控制：同时说明了上行功率控制能够克服“远近效应”等现象，从而提高了系统的容量又保证的各个用户的业务质量。     

CDMA系统的功率控制技术探讨

功率控制技术是CDMA系统中的核心技术之一，它有效的解决了远近效应。本文介绍了CDMA系统反向和前向链路的一些功率控制技术，并分析了功率控制中存在的一些问题。     

功率控制在CDMA以及实际接收机中的应用

本文从功率控制（Power Control，Pc）解决的几个现象（远近效应near—far，共道干扰co—channel，信道衰落channel fading）的定义，功率控制的分类以及不足（power based，SINR based），功率控制应用的结构种类（逆向reverse，同向forward）算法以及衰落的问题分析综述；举例说明设计接收机应该选用哪一种功率控制，举出公式以及硬件实现的对应文章分析。综述了功率控制方面的发展。     

交流电动机恒功率控制探讨

本文探讨了交流异步电动机的恒功率控制．简单介绍了调节电动机转速和转矩的方法．     

CDMA系统中的系统容量与软切换关系的研究

主要研究了CDMA移动通信系统中软切换和系统容量之间关系,介绍了CDMA系统软切换的过程以及软切换所涉及的关键参数,通过CDMA系统容量的计算方法分析得到软切换对系统容量的增减起到了一定的作用。并且在此基础上通过使用仿真工具CE4仿真得到在软切换状态下移动台发射功率和基站接收功率以及不同移动台的切换控制比例对于基站接收功率的影响,从而得出软切换可以在一定程度上提升系统容量的结论,对实际系统参数的设置有一定的指导作用。     

基于DSP异步机直接转矩控制系统的设计

介绍了异步电动机直接转矩控制系统的基本原理，阐述了基于TSM320F240DSP为核心的控制系统的设计方案和软硬件的设计方法，实践表明，该系统具有良好的性能。     

直驱式波浪发电系统的状态切换控制方法

通过对直驱式波浪发电系统的功率捕获优化方法进行研究,文中提出一种基于直线发电机的状态切换控制方法.即基于直驱式波浪发电系统中直线发电机在空载状态的速度比发电状态时的速度高的特点,控制直线发电机使其在空载状态和发电状态之间进行切换,从而提高发电机在发电状态时的运行速度,最终实现捕获功率的进一步提高.与其他功率捕获优化方法...     

采用超级电容的太阳能与市电切换系统的设计

设计一种采用超级电容作为能量的缓冲和短时储能,当外界阳光辐射能不足或超级电容暂存能量不足时自动切换到市电供电的即充即用系统.系统采用最大功率点跟踪控制方法,利用单片机控制开关管的占空比来实现光伏阵列最大功率输出,并用干扰观测法实现太阳能电池的最大功率跟踪.实验结果表明:该系统能有效地利用太阳能电池,提高系统效率和降低成本,白天基本不会切换到市电供电,符合设计要求.     

基于PLC和组态技术的异步电机综合实验系统

基于可编程控制器和组态技术,采用梯形图语言编程对异步电机进行控制以及MCGS组态软件进行组态设计,实现了对电机当前运行状态的监控;介绍了基于MCGS组态软件与欧姆龙公司CQM1H系列可编程序控制器的异步电动机综合实验系统的设计及组态过程.对系统的硬件结构和软件结构进行了详细的说明,设计了控制系统的动态监控画面;在MCGS和PLC串行通信的基础上,通过计算机控制PLC实现了对异步电动机的控制.     

Markedness and its Interpretation in Language Use

Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.     

Features of Women's language

Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women＇s language from these perspectives： pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women＇s language, more attention should be paid to language use in social context. What＇s more, the linguistic phenomena in a speaking community can be understood more thoroughly.     

An Analysis of Catherine＇s Character——Wuthering Heights

Wuthering Heights, Emily Bronte＇s only novel, was published in December of 1847 under the pseudonym Ellis Bell. The book did not gain immediate success, but it is now thought one of the finest novels in the English language. Catherine is the key character of this masterpiece, because everybody and everything center on her though she had a short life. We can understand this masterpiece better if we know Catherine well.     

Lower Paleozoic oil relationships within Williston Basin, Canada

The Williston Basin is a significant petroleum province, containing oil production zones that include the Middle Cambrian to Lower Ordovician, Upper Ordovician, Middle Devonian, Upper Devonian and Mississippian and within the Jurassic and Cretaceous. The oils of the Williston Basin exhibit a wide range of geochemical characteristics defined as "oil families", although the geochemical signature of the Cambrian Deadwood Formation and Lower Ordovician Winnipeg reservoired oils does not match any "oil family". Despite their close stratigraphic proximity, it is evident that the oils of the Lower Palaeozoic within the Williston Basin are distinct. This suggests the presence of a new "oil family" within the Williston Basin. Diagnostic geochemical signatures occur in the gasoline range chromatograms, within saturate fraction gas chromatograms and biomarker fingerprints. However, some of the established criteria and cross-plots that are currently used to segregate oils into distinct genetic families within the basin do not always meet with success, particularly when applied to the Lower Palaeozoic oils of the Deadwood and Winnipeg Formation.     

低渗透非均质砂岩油藏启动压力梯度研究

理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。     

On Tragic Consciousness In The Works By Ernest Hemingway

As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.     

Achieving Unusual States of Matter Under High Pressure

正The periodicity of the elements and the non-reactivity of the inner-shell electrons are two related principles of chemistry,rooted in the atomic shell structure.Within compounds,Group I elements,for example,invariably assume the+1 oxidation state,and their chemical properties differ completely from those of the p-block elements.These general rules govern our understanding of chemical structures and reactions.Using first principles calcula-     

Exchange-Correlation and Electronic Excitation Energies from Pairing Matrix Fluctuations

We have developed an adiabatic connection to formulate the ground-state exchange-correlation energy in terms of pairing matrix linear fluctuations.This formulation of the exchange-correlation energy opens a new channel for density functional approximations based on the many-body perturbation theory.We illustrate the potential of such approaches with an approximation based on the particle-particle Random Phase Approximation(pp-RPA).This re-     

Density Functional Theory for the Response of Periodic Systems to Electric Fields Based on the Vector Potential Approach

正The electronic and nuclear(structural/vibrational)response of 1D-3D nanoscale systems to electric fields gives rise to a host of optical,mechanical,spectral,etc.properties that are of high theoretical and applied interest.Due to the computational difficulty of treating such large systems it is convenient to model them as infinite and periodic(at least,in first approximation).The fundamental theoretical/computational problem in doing so is that     

On the Thermodynamic Limit for Responses to Static Electromagnetic Fields

For molecular systems,the quantum-mechanical treatment of their responses to static electromagnetic fields usually employs a scalar-potential treatment of the electric field and a vector-potential treatment of the magnetic field.Although the potential for each field separately is associated with the choice of an(unphysical)origin,the precise choice of the origin for the electrostatic field has little consequences for the results.This is different for the