一种低复杂度的基站信道处理器实现方法

本文提出了一种降低基站信道处理器计算复杂度的方法.通过利用插值二阶多项式滤波器对IDFT滤波器组进行整形处理,IDFT滤波器组可以直接用作基站信道处理器.实现此信道处理器的复杂度更低,因此适合在以软件无线电技术实现的基站中采用.理论分析和仿真结果表明,在保持系统性能基本不变的条件下,该方法在实现信道滤波器方面比K.C.Zangi等^[1]提出的开放滤波器组(OFB)信道处理器提高效率17%.     

半监督中文事件抽取中的模板过滤和转换方法

事件模板是指导事件抽取工作的依据,半监督方法下模板的准确性显得尤为重要.目前,基于双视图的“触发词-论元”模板的中文信息事件抽取系统不能有效地解决触发词一词多义的现象和模板稀疏现象.提出了一种借助论元进行触发词语义消歧的方法,并利用该方法进行模板过滤以消除无效模板的影响.另外,针对几种特殊的中文句型,根据句法结构提出了模板转换规则,从而提高了模板的适用性.在ACE2005中文语料上的测试表明,该方法可有效地提高半监督中文信息事件抽取系统的性能.     

Optimization of the working cycle for a hydrogen production and power generation plant based on aluminum combustion with water

The working cycle of a novel hydrogen and power generation system based on aluminum combustion with water is analyzed in order to evaluate the best performance in terms of energy conversion efficiency. The system exploits the exothermic reaction between aluminum and steam and produces thermal power for a super-heated steam cycle and hydrogen as a by-product of the reaction.     

A new reactor concept for combining oxidative coupling and steam re‐forming of methane: modeling and analysis

A new and very promising application of auto‐thermal reactors is the coupling of endothermic and exothermic reactions where the product of the endothermic reaction is the desired one. Therefore, in this work, a reactor in which oxidative coupling of methane (OCM) and steam re‐forming of methane (SRM) reactions take place simultaneously was modeled. The results were obtained in a wide range of different conditions such as inlet feed, inlet temperature, portions of OCM and SRM catalysts, and inlet velocity. In selection of the catalysts, more attention was drawn to prevent re‐forming of OCM products. The main parameters of each reaction under different conditions such as conversion of the feed components, products selectivity and yield, temperature in the length of reactor, and component's concentration in the reactor were considered in course of this study. The results revealed that simultaneous OCM and SRM reactions in one reactor will tend to be auto‐thermal, and the waste of energy will be reduced. The results also show that complete conversion of water and majority of methane and oxygen will decrease the amount of unwanted products at the reactor's discharge–a constraint that exists in single reactors of each reaction specially OCM. Copyright © 2011 John Wiley & Sons, Ltd.     

化工过程灰箱建模中采用灰色聚类技术的研究

利用灰色聚类方法建立灰箱模型,进行预测化工生产过程中催化反应的进料量和填装量等参数。实验结果表明,采用灰色聚类技术分析预测,对催化反应的数据预测结果在精度上明显优于传统化工方法,可使催化反应在原料成本最小的条件下获得较高的转化率。     

Phage‐mediated transfer of virulence genes

Bacteriophages as accessory genetic elements play a crucial role in the dissemination of genes and the promotion of genetic diversity within bacterial populations. Such horizontal transfer of DNA is critical in the emergence of new pathogenic organisms, through the dissemination of genes encoding virulence factors such as toxins, adhesins and agressins. Phages can transfer genes that are not necessary for bacteriophage persistence and are generally recognised by their ability to convert their host bacteria to new phenotypes. This phenomenon is known as phage conversion. If such converting genes encode for virulence factors, the consequences of phage infection may include increased virulence of the host bacteria, and the conversion of a non‐pathogenic strain to a potentially dangerous pathogen. A number of virulence factors in bacteria causing diseases in plants, animals and humans are encoded by converting phages, the vast majority of which are temperate as opposed to lytic in nature. © 2001 Society of Chemical Industry     

高浓度SO_2转化技术在金隆公司的应用

介绍高浓度SO2 烟气〔φ(SO2 ) 10 %～ 13%〕制酸装置转化系统的工艺设计参数和实际运行情况。采用环状中、低温催化剂和含铯环状低温催化剂 ,合理分配各段催化剂的装填量和转化率 ,对设备和管道进行良好的热膨胀补偿。装置运行情况稳定 ,转化率达到 99 8%     

Influence of the zeolite structure and acidity on the hydroisomerization of n-heptane

Different acid solids loaded with 1 wt.% of Pt have been studied in n-heptane hydroisomerization in order to determine the influence of porosity and acidity (considered measured by the activity) on selectivities. The open solids like Y and β zeolites and a pillared clay present different activities towards n-C₇ conversion but similar selectivities. Consequently, acidity seems to be a less important parameter in n-C₇ isomerization than porosity. Very different results were obtained as a function of the solid structure and so n-heptane hydroconversion appears to be a simple and rapid method to obtain data concerning the porosity of unknown zeolite structures. The highest content of multibranched isomers was obtained on open solids but the value predicted by the thermodynamic was never reached due to the fact that cracking of multibranched isomers is initiated quickly.     

略谈耐硫低变催化剂的使用

结合实际经济,论述了耐硫低变催化剂的装填、硫化、正常使用及维护应注意的一些问题。     

用Fe~0-H_2O_2氧化法处理高浓度有机废液研究

提出了用于工业废水处理的Fe0 -H2 O2 氧化法 ,并用高浓度苯酚 (5 0 0 0mg/L)和甲酚 (40 0 0mg/L)进行实验 ,结果表明Fe0 -H2 O2 氧化法在 330min后 ,DOC转化率达 80 % ,中和后污泥产生量少 ,而传统Fenton氧化法 ,同等实验条件下 ,DOC转化率仅为 6 0 % ,而且后者再提高转化率 ,中和时伴随大量污泥产生 ,因此认为Fe0 -H2 O2 氧化法优于Fenton氧化法