IPv6过渡机制讨论

本文在简要地介绍Ngtrans工作组提出的大多数过渡机制的基础上，尝试对它们进行区分、分类，并对每一种过渡机制的优缺点进行分析。另外．还对这些机制的布置以及一部分支持这些机制的产品平台进行讨论。     

WCDMA的软切换算法和TD-SCDMA的接力切换算法的分析与比较

本文概述了WCDMA的软切换算法和TD-SCDMA中的接力切换算法,分析和比较了这两种算法的各自得特点.     

Peracetic acid pretreatment of sugarcane bagasse for enzymatic hydrolysis: a continued work

Previous work has shown that the enzymatic hydrolysis of sugarcane bagasse could be greatly enhanced by peracetic acid (PAA) pretreatment. There are several factors affecting the enzymatic digestibility of the biomass, including lignin and hemicelluloses content, cellulose crystallinity, acetyl group content, accessible surface area and so on. The objective of this work is to analyze the mechanism of the enhancement of enzymatic digestibility caused by PAA pretreatment. Delignification resulted in an increase of the surface area and reduction of the irreversible absorption of cellulase, which helped to increase the enzymatic digestibility. The Fourier transform infrared (FTIR) spectrum showed that the absorption peaks of aromatic skeletal vibrations were weakened or disappeared after PAA pretreatment. However, the infrared crystallization index (N.O'KI) was increased. X‐ray diffraction (XRD) analysis indicated that the crystallinity of PAA‐treated samples was increased owing to the partial removal of amorphous lignin and hemicelluloses and probable physical change of cellulose. The effect of acetyl group content on enzymatic digestibility is negligible compared with the degree of delignification and crystallinity. The results indicate that enhancement of enzymatic digestibility of sugarcane bagasse by PAA pretreatment is achieved mainly by delignification and an increase in the surface area and exposure of cellulose fibers. Copyright © 2008 Society of Chemical Industry     

Formation of composites fabricated by exothermic dispersion reaction in A1-TiO2-B2O3 system

The formation of aluminum matrix composites fabricated by exothermic dispersion reaction in A1-TiO2-B2O3 system was investigated. The thermal analysis results show that the reactions are spontaneous and exothermic. The Gibbs free energy of α-Al2O3 is the lowest among all the combustion products, followed by TiB2 and Al3Ti. It is noted that when the B2O3/TiO2 mole ratio is below 1, the reaction products are composed of particle-like α-Al2O3, TiB2 and rod-like Al3Ti. The α-Al2O3 crystallites, resulting from the reaction between A1 and TiO2 or B2O3, are segregated at the grain boundaries due to a lower wettability with the matrix. SEM micrographs show that rod-like Al3Ti phase distributes uniformly in the matrix. When the BEO3/TiO2 mole ratio is around 1, the Al3Ti phase almost disappears in the composites, and the distribution of α-Al2O3 particulates is improved evidently.     

Local residence time,residence revolution,and residence volume distributions in twin‐screw extruders

This work was aimed at studying the overall, partial, and local residence time distributions (RTD); overall, partial and local residence revolution distributions (RRD) and overall, partial and local residence volume distributions (RVD) in a co‐rotating twin screw extruder, on the one hand; and establishing the relationships among them, on the other hand. Emphasis was placed on the effects of the type and geometry of mixing elements (a gear block and various types of kneading elements differing in staggering angle) and process parameters on the RTD, RRD and RVD. The overall and partial RTD were directly measured in‐line during the extrusion process and the local ones were calculated by deconvolution based on a statistical theory. The local RTD allowed comparing the mixing performance of mixing elements. Also it was confirmed both experimentally and theoretically that specific throughput, defined as a ratio of throughput (Q) over screw speed (N), controlled all the above three types of residence distributions, be they local, partial or overall. The RRD and RVD do not provide more information on an extrusion process than the corresponding RTD. Rather they are different ways of representing the same phenomena. POLYM. ENG. SCI., 48:19–28, 2008. © 2007 Society of Plastics Engineers     

企业以顾客为中心的营销策略过程研究

试图构建企业以顾客为中心的营销策略过程的一般模型，并利用已有的研究成果对其构成要素进行了深入分析．在此基础上，对此模型所形成的企业营销策略循环进行分类分析，并以实例说明它们所代表的现实意义，从而为企业的决策提供帮助．     

One-to-Many and Many-to-One Optical Chaos Communications Using Semiconductor Lasers

A theoretical construction of one-to-many (OTM) and many-to-one (MTO) chaos synchronization communications using semiconductor lasers is presented. One center laser provides strong injections (strong link) to other side lasers, and the side lasers also provide weak injections (weak link) to the center one. Simulation results show that the side lasers synchronize with the center laser through injection-locking. In addition, messages transmitted via the strong links or the weak links experience strong chaos pass filtering, enabling us to realize OTM and MTO communications.     

美国火灾报警系统的新技术需要更多的培训

如今市场上大多数火灾报警系统的运行需要程序化的软件。随着软件技术的发展，消防行为已担心在安装的可靠性上可能下降。 如今的软件技术为火灾报警系统提供了更多灵活的和可操作的控制，安装维修系统的技艺更灵活更可操作控制需要更多的投资。但是这种灵活的和可操作的控制是需要成本的，还需要安装和维修系统的技术人员掌握一定的工程技巧。     

Space–Time Power Schedule for Distributed MIMO Links Without Instantaneous Channel State Information at the Transmitting Nodes

A space-time optimal power schedule for multiple distributed multiple-input multiple-output (MIMO) links without the knowledge of the instantaneous channel state information (CSI) at the transmitting nodes is proposed. A readily computable expression for the ergodic sum capacity of the MIMO links is derived. Based on this expression, which is a non-convex function of power allocation vectors, a projected gradient algorithm is developed to optimize the power allocation. For a symmetric set of MIMO links with independent identically distributed channels, it is observed that the space-time optimal power schedule reduces to a uniform isotropic power schedule when nominal interference is low, or to an orthogonal isotropic power schedule when nominal interference is high. Furthermore, the transition region between the latter two schedules is seen to be very sharp in terms of nominal interference-to-noise ratio (INR). For MIMO links with correlated channels, the corresponding space-time optimal power schedule is developed based on the knowledge of the channel correlation matrices. It is shown that the channel correlation has a great impact on the ergodic capacity and the optimality of different power scheduling approaches.     

塔顶放大器在工程设计中的应用探讨

塔顶放大器在移动通信领域有较为广泛的应用，它通过降低(改善)等效接收噪声系数，从而提高上行接收灵敏度。本文将简要介绍塔顶放大器的应用和提高接收机灵敏度的计算。