非损伤光嫩肤技术的最新进展

非损伤激光嫩肤技术作为一种很有前途的技术 ,它的优点是保护表皮不受损伤而刺激真皮胶原蛋白的再生 ,预防和治疗皮肤衰老 ,目前这种技术尚处于探索阶段。本文根据光源类型介绍了非损伤光嫩肤技术的最新进展 ,并探讨目前的研究热点和存在的难题 ,为进一步的研究提供参考     

NC—2T系列机芯加装KAIDA系列遥控频道转换噪声及消除方法

本文分析了彩色ＮＣ－２Ｔ系列机芯加装ＫＡＩＤＡ系列遥控功能后产生频道转换品噪声的原因及消除方法。     

Channel length influenced contribution of hole and electron trapping effect to threshold voltage stability in organic field effect transistors

Effect of channel length on hysteresis and threshold voltage shift in copper phthalocyanine (CuPc) based organic field effect transistors was studied. Contrary to expectation, longer channel length devices exhibited minimum threshold voltage shift. Influence of channel length on the contribution of hole and electron trapping to threshold voltage stability was determined. Shortest channel length devices exhibited highest electron trapping effect while longest channel devices exhibited minimum hole as well as electron trapping. Lower hole trap effect for longer channel length devices was suggested to be due to reduced longitudinal field between source and drain electrodes while minimum electron trapping was attributed to suppression of drain current by increased hole trap centres.     

Performance Analysis of a Novel Cooperative Diversity Scheme

The traditional cooperative diversity could improve the system performance enormously, which has already widely been investigated by researchers. How-ever, it didn＇t exploit channel code and Distributed space-time block code （DSTBC） together to achieve both diversity gain and coding gain. Therefore, in order to further improve system performance, a novel cooperative diver-sity scheme based on concatenating the channel code and DSTBC is proposed in this paper. The closed-form expres-sions of channel capacity, outage probability and Bit error rate （BER） are derived to evaluate the performance of the proposed scheme. Also, computer simulations are conducted to validate our scheme, showing that, even though the interuser channel is noisy, the proposed scheme out-performs the traditional cooperative diversity in terms of channel capacity, outage probability and BER with distinct system gains.     

稀疏码分多址系统一种改进的检测算法

稀疏码分多址(SCMA)系统中基于球形译码算法(SD)由于具有优良的性能受到越来越多的关注,然而现有基于SD的算法只能用于某些特定星座结构的检测,导致其应用受限.该文提出一种适用于任意星座且性能达到最大似然(ML)算法性能的改进球形译码(ISD)算法.该算法将用户星座图拆分,并将用户星座图转换为多层树结构,利用对树结构...     

皮肤阻抗检测系统隔离刺激器的设计与实现

隔离刺激器是皮肤阻抗检测系统中重要的组成部分,根据检测系统的具体要求,提出一种新型的刺激器设计方案。该方案采用LM317HV调整刺激器信号的电压输出幅度,最高可达80 V;通过HV632调整输出脉冲的宽度和周期,从而实现一个幅度、脉宽和周期均可调的高压脉冲发生器。该刺激器具有操作简便、性能稳定、精度高和脉冲波形好等优点,可广泛应用于需要高压可调脉冲的场合,亦可对其进行扩展,满足具体的工程需求。     

Personally customizable content authoring service for Internet Protocol television subscribers

In this paper, we propose a personally customizable content authoring service (C2Channel) using an Internet Protocol television (IPTV) platform, in which a user terminal such as a PC or set‐top box sends various kinds of multimedia files from a camera or camcorder to a remotely located authoring server (C2Channel server). The C2Channel server creates personalized content in real time by combining special effects with the multimedia files transmitted from the user terminal and then retransmits them to a predefined relevant service group as a personal IPTV channel through an IPTV network provider. This content authoring service supplies an automatic multimedia editing/composition service and offers unicast, multicast, and groupcast services for a large number of interested groups via an IPTV‐based real‐time media delivery platform (Open Live IPTV Engine [OLIVE]), in which a service management server is used for user identification through the IPTV personal channel. Because this platform uses a remote server resource when authoring personally customizable content, resources remaining at the user's terminal can be variously utilized. Copyright © 2012 John Wiley & Sons, Ltd.     

An optimal scheduling and routing under adaptive spectrum-matching framework for MIMO systems

Multi-users (MUs) along the communication links cause noise and traffic in the channel. The prediction of availability and the optimal usage of channels are the main objectives of the multi-input multi-output (MIMO) system. Several optimisation algorithms select the optimal channel for the users effectively. But the high-error rate and the probability values are the two major problems in traditionally optimised channel selection methods. The bandwidth allotted for information transmission is minimum. Moreover, the outage probability values are maximum in traditional scheduling algorithms. This paper proposes the new optimisation algorithm that predicts the channels for transmission and adaptive spectrum matching concept to predict the suitable channel from allocated bands. Also, the prioritisation on high-spectrum intensity basis assures an efficient data delivery to the receiver. The scheduling of available channels and data prioritisation minimises the error probability rates. This paper investigates the effectiveness of proposed optimal channel utilisation against the different modulation schemes such as three-dimensional complementary codes, linear network coding with the quadrature phase shift keying in terms of the average block error probability and bit error rate.     

基WMSA信道估计技术的WCDMA上行链路性能分析

本文对用控制信道中的导频符号,有杉多时隙加权平均信道估计技术的ＷＣＤＭＡ上行链路进行了性能仿真研究。仿真结果表明,参与信道估计的时隙数目、加权系数的选取应针对不同的信道衰落环境。结合仿真结果,讨论分析了前向纠划、ＲＡＫＥ接收机的指峰数及信道中可分解路径的平均功率之差对ＷＣＤＭＡ上行链路性能的影响。     

High SNR sum capacity analysis of BD MIMO BC systems with imperfect CSI

We investigate the sum capacity of Block Diagonalization precoding Multiple Input Multiple Output Broadcast Channels (BD MIMO BC) with imperfect Channel State Information (CSI) at the base station. Since it is difficult to obtain the exact expression, a lower and an upper bounds of the sum capacity under Gaussian channel estimation errors are drived instead. Analyses show that the gap between two bounds is considerably tight at all Signal to Noise Ratio (SNR) region. From the lower bound of the sum capacity, we can see that the multiplexing gain tends to be zero at high SNR region, which indicates that the BD MIMO BC system with channel estimation errors is interference-limited at high SNR.