LDPC-Coded Cooperation with Receive Multi-Antenna and Unknown CSI in the Destination

This paper studies a coded cooperation scheme with receive multi-antenna in the destination. A kind of simple-encoding irregular systematic low-density-parity-check (LDPC) codes is applied to the scheme. For Rayleigh block fading channels, in the unknown channel state information scenario, space-based adaptive least-mean square (LMS) transversal filters are adopted in the destination to realize receive diversity gain. The filtered signals from the source and relay are decoded by a joint “Min-Sum” iterative decoding algorithm. This algorithm agrees with the bilayer Tanner graph that can be used to fully characterize two distinct irregular systematic LDPC codes employed by the source and relay. Simulation results verify the effectiveness of the space-based adaptive LMS transversal filters in the coded cooperation scheme. Meanwhile, theoretical analysis and numerical simulation show that the proposed coded cooperation scheme can well combine cooperation diversity, multi-receive diversity and channel coding gains, and clearly outperforms the coded non-cooperation one under the same conditions.     

直流反应磁控溅射法制备CdIn2O4薄膜的光电性能研究

利用直流反应磁控溅射法制备了CdIn2O4(CIO)薄膜,研究了氧浓度、基片温度、溅射时间和退火处理对薄膜光电性能的影响.结果表明电阻率随着氧浓度的增加和溅射时间的减小而增加,随着基片温度的升高先减小后增加;透光率随着氧浓度、基片温度的增加和溅射时间的减小而增加.退火处理后,薄膜的电阻率降低,光吸收边发生"蓝移".点缺陷对薄膜的光电性能产生重要影响,光吸收边的移动是"Burstein-Moss"效应和多体效应共同作用的结果.综合实验结果和理论研究,推荐了直流反应磁控溅射法制备CIO薄膜的最佳条件.此条件下制备薄膜的电阻率为2.95×10-4 Ω·cm,波长为628 nm时薄膜的透光率高达91.7%.     

先进树脂基结构复合材料的发展EI

综述了先进树脂基结构复合材料的发展现状，分析了目前树脂基复合材料制备技术、性能评定及结构设计方面的问题，提出了今后先进树脂基复合材料的发展方向。     

助老助残服务机器人家庭环境下标签的识别

在复杂的家庭环境下视觉干扰物太多,因此作者通过使用标签技术来识别目标.设计了一种专门的标签,以标签各个部分的颜色和它们的组成结构作为标签的图像特征.提出了一种有效的连通分量结构法,以标签各部分各个之间的位置关系作为判断依据,从而实现了标签的识别.同时也能通过识别标签的一些特征来判断标签所代表的目标的类型及其状态.图像处理的准确结果为接下来的伺服控制打下了良好的基础.     

影响蜂窝夹层结构滚筒剥离强度主要因素的研究EI

对预浸料与蜂窝直接接触共固化成形的蜂窝夹层结构的滚筒剥离强度进行了研究，主要讨论了树脂基体、预浸料树脂含量及织物构成对滚筒剥离强度的影响。     

电力信息系统的耦合建模方法

考虑电力网和信息网的耦合,对建立电力信息系统模型具有重要意义。本文以IEEE9节点系统为例,首先分析系统的运行机理,描述信息网和电力网之间的数据闭环流动全过程。然后,利用矩阵描述系统内部数据传输结构,进而建立考虑电力网和信息网耦合关系的电力信息系统模型。最后,通过PowerFactory分析负荷变化时,该模型仍可保持节点电压稳定这一特点,验证了模型的准确性。     

Distributed polar-coded OFDM based on Plotkin’s construction for half duplex wireless communication

A Plotkin-based polar-coded orthogonal frequency division multiplexing (P-PC-OFDM) scheme is proposed and its bit error rate (BER) performance over additive white gaussian noise (AWGN), frequency selective Rayleigh, Rician and Nakagami-m fading channels has been evaluated. The considered Plotkin’s construction possesses a parallel split in its structure, which motivated us to extend the proposed P-PC-OFDM scheme in a coded cooperative scenario. As the relay’s effective collaboration has always been pivotal in the design of cooperative communication therefore, an efficient selection criterion for choosing the information bits has been inculcated at the relay node. To assess the BER performance of the proposed cooperative scheme, we have also upgraded conventional polar-coded cooperative scheme in the context of OFDM as an appropriate bench marker. The Monte Carlo simulated results revealed that the proposed Plotkin-based polar-coded cooperative OFDM scheme convincingly outperforms the conventional polar-coded cooperative OFDM scheme by 0.5 ~ 0.6 dBs over AWGN channel. This prominent gain in BER performance is made possible due to the bit-selection criteria and the joint successive cancellation decoding adopted at the relay and the destination nodes, respectively. Furthermore, the proposed coded cooperative schemes outperform their corresponding non-cooperative schemes by a gain of 1 dB under an identical condition.     

制水厂氯气储存及使用安全问题探讨

氯气作为一种消毒剂被制水行业广泛应用于饮用水消毒,但氯气是一种剧毒物品,若管理不善或使用不当,将会对人和设备造成恶性伤害。经过多年的实践和探索,总结出制水行业储存、使用氯气过程中的几大问题,为制水行业安全使用氯气提供借鉴。     

我国复合材料工业的发展概况

回顾了我国复合材料发展历史。通过列举玻璃纤维、ACM用特种纤维等增强材料和不饱和聚酯树脂、环氧树脂、酚醛树脂等基体材料以及复合材料机械化成型进展情况,纤维缠绕管道与贮罐、压力容器、SMC／BMC、拉挤型材等技术产品开发情况,介绍了我国复合材料的发展。     

一种可实现高精度时间同步的数据传输方法

KM2A探测器阵列是高海拔宇宙线观测站(LHAASO)的主体探测器阵列之一,近7000个探测器平均分布在1.3 km 2的实验范围内。针对大面积分布式布局的高能物理实验中读出电子学系统的时间同步和数据传输问题,提出一种可实现高精度时间同步的数据传输方法。借助TCP/IP协议栈和White Rabbit时钟同步技术融合时钟网络与数据网络,TCP/IP协议栈在仅保留PC通信协议的基础上,无需增加额外硬件,即可实现高效可靠的数据传输和高精度时钟同步。测试结果表明,该方法可以实现探测器阵列内LHAASO KM2A读出电子学插件间时间同步精度优于1 ns,同时保证了数据传输的可靠性。