Novel time-frequency differential space-time modulation for multi-antenna OFDM systems

1.INTRODUCTIONRecently,there has been considerable interest in thewireless communication system with multiple trans-mit and receive antennas[1,2].So far,most researchon space-ti me modulation has assumed that accuratechannel esti mations are available at the receivers.Differential space-ti me(DST)modulationschemes were proposed to achieve diversity gainswithout channel state information(CSI)[3].DSTmodulation schemes allowfor slowly changing chan-nels that have to remaininvariant within…     

单模激光定态几率分布的内插近似

用内插程序计算了单模激光的定态几率分布，并将其结果和数值模拟及统一色噪声近似理论的结果，在不同噪声关联时间τ值的情况下进行了比较．发现在激光系统中用内插法得到定态几率分布，不仅在大τ和小τ的情况下和数值模拟曲线吻合，而且对中等范围取值τ也和数值模拟结果吻合．     

双酚功能化的咪唑盐一种新的断裂方式

双酚功能化的咪唑盐在K2CO3存在下会发生断裂,生成了1-(4,6-二叔丁基-2-羟基苄基)咪唑,其通过了核磁、元素分析和X-Ray单晶衍射的表征.     

集中质量矩阵替代一致质量矩阵的合理性与局限性

文中分析了集中质量矩阵取代采用一致质量矩阵后对体系自振频率造成的误差,并指出集中质量矩阵应该有条件的使用。并根据相对容许误差,给出了实际计算中采用集中质量矩阵时单元尺寸的选取方法。     

超载、高温条件下半刚性基层沥青路面车辙试验研究

采用车辙试验检验沥青路面抗车辙能力的方法,介绍了沥青混和料车辙试验的试验过程,并分析了高温和超载对动稳定度的影响,最后对减小车辙病害提出了建议.     

结合GFDM的空间调制技术及其检测算法研究

针对SM-OFDM系统不能很好适应未来5G通信系统的问题,提出了结合广义频分复用(generalized frequency division multiplexing, GFDM)的空间调制(spatial modulation, SM)系统SM-GFDM。利用矩阵的稀疏性,研究了一种低复杂度的SM-GFDM系统检测算法,对比了在GFDM接收端分别采用基于矩阵稀疏性的MF(matched filtering),ZF(zero-forcing),MMSE(minimum mean-square error)检测算法时的系统误码率。仿真结果表明,在SM端采用ML(maximum likelihood)检测的前提下,GFDM端采用基于矩阵稀疏性的MMSE检测算法时可获得较低的误码率,与传统的MMSE检测算法相比,其复杂度有所降低。同时进一步仿真对比了SM-GFDM系统、SM-OFDM系统以及V-BLAST GFDM系统的BER曲线,结果表明,SM-GFDM系统与SM-OFDM系统相比误码率略有上升,但却优于V-BLAST GFDM系统。结合SM技术的特点,SM-GFDM系统可以很好地适用于未来5G系统。     

The heteromeric cyclic nucleotide-gated channel adopts a 3A:1B stoichiometry

Cyclic nucleotide-gated (CNG) channels are crucial for visual and olfactory transductions. These channels are tetramers and in their native forms are composed of A and B subunits, with a stoichiometry thought to be 2A:2B (refs 6, 7). Here we report the identification of a leucine-zipper-homology domain named CLZ (for carboxy-terminal leucine zipper). This domain is present in the distal C terminus of CNG channel A subunits but is absent from B subunits, and mediates an inter-subunit interaction. With cross-linking, non-denaturing gel electrophoresis and analytical centrifugation, this CLZ domain was found to mediate a trimeric interaction. In addition, a mutant cone CNG channel A subunit with its CLZ domain replaced by a generic trimeric leucine zipper produced channels that behaved much like the wild type, but less so if replaced by a dimeric or tetrameric leucine zipper. This A-subunit-only, trimeric interaction suggests that heteromeric CNG channels actually adopt a 3A:1B stoichiometry. Biochemical analysis of the purified bovine rod CNG channel confirmed this conclusion. This revised stoichiometry provides a new foundation for understanding the structure and function of the CNG channel family.     

Dieldrin and endrin removal from water by triolein-embedded adsorbent

A novel triolein-embedded adsorbent for removal of persistent organic pollutants （POPs） from water was developed. In this paper, taking dieldrin and endrin as the target pollutants, different factors （temperature, ion strength, pH, and concentration of humic acid） that affect the adsorption rate were investigated. Adsorption isotherms of these two pollutants fitted to Freundlich model well identified the partition mechanism between the adsorbent and water. However, the equilibrium constant of dieldrin was larger than that of endrin due to larger octanoi-water coefficient of dieldrin. Adsorption rate of dieldrin increased with the increase of temperature, the decrease of ion strength, pH and concentration of humic acid, whereas adsorption rate of endrin decreased with the increase of temperature and pH. Humic acid firstly increased, and then decreased the adsorption rate of endrin. Ion strength hardly affected the adsorption rate of endrin.     

BSO晶体空间光学双稳态的理论分析

本文对基于ＢＳＯ（硅酸铋）晶体的电控自聚焦效应实现空间光学双稳态进行了理论分析，在理论上给出输出光强随输入光功率变化的“Ｓ”形关系曲线．     

矿井通风机励磁控制线路的改进

针对矿井通风机励磁电压易波动等问题，以使用较为广泛的KGLF11型可控硅励磁装置为基础，采用以TC787AP为核心的新型移相电路，彻底解决了因元器件的选用及控制原理的欠缺引起的波动问题，从而实现了控制系统安全、可靠、高效的运行。