电缆附件国产高压电缆走向市场的最大障碍

"电缆附件是个高利润率的产品,它的利润远高于电力电缆.现在正有企业逐渐挤入这个行业,但这一行业有门槛,技术难度大,投资高.国内基本还处于仿制阶段." 北京电力电缆公司副经理李华春告诉记者.在高压电缆这一利润较高产品引起业内众多媒体关注时,高压电缆附件似乎被很多人忽视了.而这一与电缆相比用量少的多的附件却已经影响到国内高压电缆的销售.……     

以环保品质打造绿色厨房概念——海尔橱柜亮相“中国广州国际厨房家具和电器展览会”

首届《中国广州国际厨房家具和电器展览会》(简称:广州厨房展)将于2008年3月27日在广州中国进出口商品交易会琶洲展馆隆重登场。该展会是由德国科隆国际展览有限公司(Koelnmesse GmbH)     

SINOCES将在青岛举行

日前获悉,一年一度的SINOCES(中国国际消费电子博览会)将于2008年7月10日～13日在青岛拉开帷幕.据组委会人士介绍,今年参展商招募情况十分乐观,松下、惠普、甲骨文、GE、杜比实验室、东芝、蓝光、海尔、TCL、海信、长虹、闪联等企业和机构均表示参加,并有望展出与互联网有关的最新消费电子产品;沃尔玛、百思买、家乐福,百思买、国美、苏宁等届时也将到会采购.     

改革开放焕发STI英姿与时俱进再创STI辉煌

2005年夏天,花繁叶茂,STI迎来了45华诞. 45年,弹指一挥间,STI已由一株幼苗长成为一棵参天大树.为了STI的今天,我国德高望重的著名变压器专家汤明奇、周茂培、王文铮、周仲民、史习禁、朱英浩、于海年、贺以燕、陈道辉、张文相、李文海等白发染鬓的老一辈奉献了他们的一生心血,任重道远的中年人奉献了他们的青春年华,意气风发年轻人正在将他们的满腔热血奉献给一代又一代STI人开创的变压器事业.     

流水线结构RS译码器的超大规模集成电路设计

RS码已经广泛地应用于通信系统、数字电视和计算机存储系统中,用来提高数据可靠性.以数字电视广播(DVB)标准中定义的RS(204,188)译码器为例,详细介绍了改进的欧几里德(ME)算法及以此算法为基础的RS译码器的超大规模集成电路VLSI实现,采用了流水线结构,对译码器的各个模块进行了分析和建模.通过对流程的仿真和综合验证,发现这些模块能较好的满足设计要求,能纠正不大于8个的误码.     

假名牌市场的存在机理及其对策分析

假名牌市场的普遍存在,严重扰乱了我国社会主义市场经济秩序,影响了企业间的公平竞争,同时也反映出目前我国消费市场上,市场运行机制不完善,政府执法监督不严等诸多问题.结合对假名牌市场相关信息的调查数据,本文通过对假名牌市场的现状,以及给我国市场经济所带来的危害分析,从消费者,制造商、政府三方面探讨了假名牌市场存在的原因,再针对我国目前在打击假名牌方面存在的问题,参考国外的打假经验,提出了几点打假建议.     

核2、3级承压设备制造过程中的成型工艺评定——RCCM标准和ASME规范的应用体会

随着我国核电建设高潮的到来,越来越多的核级设备制造将实现国产化,目前,2个主要的核电技术标准RCCM和ASME也正得到或将得到广泛的应用.通过对这2个标准在核2、3级承压设备制造过程中的要求和成型工艺评定方面的比较,列出了2个标准要求的侧重点和按2个标准实施成型工艺评定的不同之处,以期给读者有益的启迪及参考.     

将并购进行到底国美控股三联商社

现场参与竞拍的有4位竞买人,每家缴纳1000万元保证金,牌号分别为11、18、77、88。上午九时,拍卖会正式开始。当每股竞价很快达到6元以上后,竞拍人只剩下77号与11号竞买方。此后,双方进行了一场堪称"疯狂"的竞价,拍卖师以不足一秒一价的速度提高着喊价。当每股竞拍价格升至16.8元时,代表三联集团的77号中年男子稍有迟疑,接了个电话。随后双方继续加价,竞拍价到19.9元时,77号竞拍人停下来打了一个电话,随后无奈地放弃了竞价……     

天正：登高望远 借势突围——访天正集团销售总公司总经理高天放

2004年对于天正集团而言是不同寻常的一年。不论是参与南京“三联动”企业改制成功收购南京市机电产业集团下属的耐特机电集团公司和容光达电子有限公司,还是在南京江宁区投资1.5亿元打造变压器产业基地,或者是收购内蒙古电线电缆厂,都引起了业内外人士的广泛关注。天正,正在发     

奇迪在竞争中凸显实力

饮水机市场混乱,质量良莠不齐有数据显示,全国家庭饮水机的拥有量已经超过1.2亿台,仅去年我国饮水机市场就已达到3300万台的销量。据不完全统计,2006年在国内市场上销售的饮水机品牌大约500多个。我国最大的饮水机产业基地——慈溪地区,就聚集了200多家饮水机生产企业。众多良莠不齐的企业混在一起,严重威胁着规范企业的生存,阻碍了行业的进步。     

Control strategies for semiconductor-quantum-dot-based single and double qubits

External quantum control of qubits poses an inverse problem known as Hamilton identification. We present several strategies for achieving specific physical operations, such as driving a system along a specified quantum trajectory, state trapping, entanglement generation in quantum gate realizations, and state-independent quantum operations.     

Quantum correction for DG MOSFETs

The characteristics of modern semiconductor devices are strongly influenced by quantum mechanical effects. Due to this fact, purely classical device simulation is not sufficient to accurately reproduce the device behavior. For instance, the classical semiconductor equations have to be adapted to account for the quantum mechanical decrease of the carrier concentration near the gate oxide. Several available quantum correction models are derived for devices with one single inversion layer and are therefore only of limited use for thin double gate (DG) MOSFETs where the two inversion layers interact. We present a highly accurate quantum correction model which is even valid for extremely scaled DG MOSFET devices. Our quantum correction model is physically based on the bound states that form in the Si film. The eigenenergies and expansion coefficients of the wave functions are tabulated for arbitrary parabolic approximations of the potential in the quantum well. Highly efficient simulation of DG MOSFET devices scaled in the decananometer regime in TCAD applications is made possible by this model.     

Photon Number Resolving Detector at Telecom Wavelengths: Charge Integration Photon Detector (CIPD)

A photon number resolving detector (PNRD) is the basic device for many optics applications, especially for developing optical quantum computer. The implementation of universal nonlinear quantum gates typically requires high quantum efficiency and a wide dynamic range up to a few tens of photons. We have developed a charge integration photon detector (CIPD) as a PNRD with a quantum efficiency of 80% and multiphoton measuring over ten photons at telecom wavelengths. This detector has a signal-to-noise ratio of 3 and operates at 40 Hz at present. In this paper, we introduce the principle of our CIPD and report the capability of detecting different types of photon statistics with a high linearity to incident photon numbers.     

Adaptive actuator failure compensation for cooperative robotic manipulators with parameter uncertainties

This article develops a new framework of adaptive actuator failure compensation control for cooperative manipulator systems with parameter uncertainties in addition to actuator failures, and designs and analyzes effective actuator failure compensation schemes for such robotic systems. The new adaptive control design uses an integration of multiple individual failure compensators and direct adaptation to handle various types of uncertainties in such robotic systems. The design can also be used for concurrent actuator failure cases, to expand the capability of adaptive actuator failure compensation. With a complete proof and performance analysis, it is shown that the proposed control scheme guarantees the desired closed-loop stability and asymptotic output tracking, despite actuator failures whose patterns, time instants and values are all unknown. Simulation results of a benchmark cooperative manipulator system are presented to verify the desired control performance of the system with both typical constant and square-wave actuator failure signals.     

Simulation of Entanglement Dynamics for Scattering Between a Free and a Bound Carrier in a Quantum Wire

The decoherence of a quantum system is ascribed to its enetanglement with another system considered as the environment, thus the quantitative evaluation of entanglement formation dynamics can shed light on the transition between quantum and classical behavior of a carrier that undergoes to a scattering event. We present here a numerical solution of the time-dependent 1D Schroedinger equation of a two-particle system consisting of a free carrier scattered by a bound one. The real-space entanglement between them is computed, at different times, for various initial conditions. The maximum entanglement corresponds to equal probability of transmission and reflection of the free particle.     

A navigation system for increasing the autonomy and the security of powered wheelchairs.

Assistive technology is an emerging area where some robotic devices can be used to strengthen the residual abilities of individuals with motor disabilities or to substitute their missing function thus helping them to gain a level of independence at least in the activities of daily living. This paper presents the design of a navigation system and its integration with a commercial powered wheelchair. The navigation system provides the commercial wheelchair with a set of functions which increase the autonomy of elderly and people with motor disabilities. In general, a robot device must be adapted to assistive applications in such a way as to be easily managed by the user. Users, especially young ones, prefer to directly control the robotic device and this aspect of usability has to be managed without affecting the security and efficiency of the navigation module. These aspects have been considered as specifications for the navigation module of powered wheelchairs. Different autonomy levels of the navigation module and proper user interfaces have been developed. Two autonomy levels have been designed. Simple collision avoidance is also implemented in order to stop the mobile base when an obstacle is detected. The preliminary technical tests performed on the navigation system have shown satisfactory results in terms of security and response time. A modular solution for the navigation module was considered in order to simplify the adaptation of the module to different powered wheelchairs.     

Quantum Imaging

One of the most surprising consequences of quantum mechanics is the entanglement of two or more distant particles. Although questions regarding fundamental issues of quantum theory still exist, quantum entanglement has started to play important roles in practical engineering applications. Quantum imaging is one of these exciting areas. Quantum imaging has demonstrated two peculiar features: 1) reproducing "ghost" images in a "nonlocal" manner and 2) enhancing the spatial resolution of imaging beyond the diffraction limit. In this paper, we start with the review of classical imaging to establish the basic concepts and formalisms of imaging. We then analyze two-photon imaging with particular emphasis on the physics of spatial resolution enhancement and the "ghost" imaging phenomenon.     

Effects of scattering resonances on carrier-carrier entanglement in charged quantum dots

We address the problem of the entanglement generation in an electron-scattering by a 1D double-barrier resonant tunnelling device. In particular we analyze the role played by transport resonances in the appearance of quantum correlations between the energy states of the electrons. The entanglement is not sensitive to the presence of Breit-Wigner resonances, while it may be controlled by manipulating Fano resonances. Such a behavior is ascribed to the different mechanisms characterizing the two types of processes.     

Error models for long-distance qubit teleportation

A recent proposal for realizing long-distance, high-fidelity qubit teleportation is reviewed. This quantum communication architecture relies on an ultrabright source of polarization-entangled photons plus a pair of trapped-atom quantum memories, and it is compatible with long-distance transmission over standard telecommunication fiber. Models are developed for assessing the effects of amplitude, phase, and frequency errors in the entanglement source, as well as fiber loss and imperfect polarization restoration, on the throughput and fidelity of the system.     

面向电力场景的量子保密通信纠缠退化理论模型

基于纠缠态作为信息载体的量子保密通信技术中,纠缠是其中的核心资源。如何保证通信中双光子态的纠缠度是量子保密通信的主要问题之一。研究了基于单模光纤的量子保密通信过程中的环境噪声,特别是电力架空光缆所处恶劣环境引入的噪声,可能导致量子纠缠退化的模型。分别从折射率的各向异性和吸收系数的各向异性讨论了环境噪声引起的量子纠缠横向退相干和纵向退相干效应。研究结果将对基于纠缠技术的量子保密通信在电力系统及其他恶劣电磁环境中的应用提供一定的参考。