一种新改进的DS/CDMA多用户检测器

提出了一种利用盲信号分离技术(BSS)与RAKE接收相结合的新多用户检测器.利用基于高阶累积量快速定点的独立分量分析(ICA)算法,从CDMA系统的多址干扰信号中较好地分离出需要用户的多径混合信号和多址干扰信号,进而通过RAKE接收需要的用户信号.     

用ASP和SQL Server建立高校科研信息管理系统

根据高校科研管理的特点对高校科研管理信息系统的需求进行了研究,提出了采用微软公司的ASP SQL Server系统的解决方案,该方案采用B rowser/Server结构,浏览器的客户端无需安装任何组件,就可以使用本系统的所有功能;探讨了该解决方案的需求分析、程序设计、程序测试的全过程,系统总结了建立高效率科研管理信息系统的方法.     

A Class of Second-Order Consensus Protocol in Multi-Agent Systems with Multiple Input Delays

This paper is concerned with the consensus problems for second-order multi-agent systems with multiple input delays. Different from all standard consensus algorithms with uniform delays, the authors aim to find the largest input-delay margin which can guarantee the consensus for the case when delays are nonuniform. Based on frequency domain analysis and matrix theory, an upper bound for maximum tolerable input-delay is given in terms of the relationship with scaling strengths and largest eigenvalue of the Lapalician matrix. Simulation results are provided to illustrate the obtained results.     

基于SolidWorks 渐开线齿轮的三维辅助设计

探讨了基于SolidW orks的二次开发技术,研究如何利用V isual Basic程序语言在SolidW orks中强大的三维绘图功能进行计算机三维辅助设计;并以渐开线齿轮的设计与绘制为例,提出了通过程序计算后利用SolidW orks曲线连接阵列点构建封闭齿廓的方法。实践证明该方法为其它CAD二次开发平台绘画渐开线齿轮提供可借鉴之处。     

窖水中主要无机离子对光催化灭除大肠杆菌(E.coli)的影响研究

采用自主开发的N-TiO_2作为光催化剂,在流动相光催化反应装置中,对窖水中所含Ca~(2+)、Cl~-、CO_3~(2-)、HCO_3~-、SO_4~(2-)等主要无机离子对光催化剂灭除E.coli的影响,以及复配模拟窖水和实际窖水对光催化灭除E.coli的影响进行了实验研究,并分析了其影响机理。实验结果表明:Ca~(2+)、HCO_3~-对光催化灭除E.coli有抑制作用,CO_3~(2-)对光催化灭除E.coli有明显的促进作用,而SO_4~(2-)、Cl~-对光催化灭除E.coli无影响。在对实际窖水进行光催化灭除E.coli菌落总数的实验中,经60min反应,窖水中菌落总数和总大肠菌群均为零,达到国家饮用水卫生标准,说明自主开发的NTiO_2光催化剂在农村窖水深度处理灭除E.coli效果好,可推广应用。     

Diet composition of an invasive population of Lithobates catesbeianus (American Bullfrog) from Argentina

The American bullfrog Lithobates catesbeianus has been introduced around the world, with invasive populations reported from almost all South American countries. A population of this species was introduced in the Calingasta department of San Juan province, which is an arid environment in western Argentina. This work provides information on the dietary composition of an invasive population of L. catesbeianus, and compares the degree of dietary overlap between adults and juveniles. Stomach contents of 169 bullfrogs (82 adults and 87 juveniles) were analysed. Adults consumed 40 prey taxa and Hymenoptera (Insecta) was the most numerous prey item (41.8%), followed by Araneae (13.6%) and Aeglidae (13.4%). Juveniles consumed 29 prey taxa and Hymenoptera constituted the highest percentage in prey number (77.2%). The trophic overlap niche index at the same level shows a value of 0.64 overlap in dietary community between adults and juveniles of this bullfrog. Aeglidae was volumetrically the most important trophic item (25.4%), followed by Anura (25.02%). Our results showed that cannibalism in bullfrogs is more common than the consumption of native anurans, coinciding with that reported in other populations of introduced bullfrogs. The high similarity in the diets of both size classes and the association between the size of the predator and prey suggest that the impact caused by bullfrogs throughout their ontogeny is high and probably has an impact on their prey. Freshwater crabs are the main items in the diet of Lithobates catesbeianus in other introduced populations and are usually the most conspicuous at our study site. The crabs in freshwater ecosystems are part of the lowest trophic level in the food chain. The major threats to the southern region’s freshwater crabs include deforestation, farming and exotic species. Lithobates catesbeianus has a generalist diet and high overlap between adults and juveniles.     

玉米套种的栽培技术要点

简要介绍了玉米套种甘蓝复播架豆角的栽培技术及其收益.     

颈型颈椎病功能锻炼的研究概述

近年来,颈型颈椎病的发病率不断增高,对人们的工作、生活造成严重影响。研究表明,功能锻炼对颈型颈椎病的康复有重要作用,功能锻炼的方法分为传统中医气功锻炼法、肌力锻炼和保健操3类,这些方法实用、有效、方便,在颈型颈椎病的治疗中可以综合运用这些方法,从而在更短的时间里收到比以往更好的疗效。     

科技智库研究方法:进展与趋势

 对全球科技智库的学科领域、理论体系、具体方法以及实践成果进行了调研与分析。调研结果显示,经济管理、政治法律、安全社会、能源环境等学科领域是科技智库研究方法关系网的核心,交通建筑、天文地学、生物医药、材料化学、数学物理、信息通信等学科领域处于辅助地位。科技智库的研究理论经由科技规划、科技评估、科技路线图的实践,逐渐向DⅡS研究体系发展。科技智库研究的具体方法可分为数据收集方法、信息整合方法、综合研判方法、方案构建方法4类,具有多主体、多对象、多介质、多因子、多组合、多渠道、多层次、多维度、多阶段、多角色等特征。随着科学技术在公共服务和决策咨询中的应用,科技智库的研究方法以可视化平台、跟踪调查平台、综合检索平台为依托,将进一步深化、拓展、完善。     

新中国成立以来科技研发经费体系的发展

 梳理了新中国成立以来科技研发经费体系的发展历程。以科技研发经费发放全过程为视角,分析了科技研发经费发放主体、数量、领域及类别、对象。通过数据描述和文本分析,发现：（1）各部委尤其是财政部和科技部是政府经费发放的主体,财政部主要负责财政拨款,科技部主要负责经费分配,但总体来说企业在科技研发中投入更多经费;相应地,R&D经费支出的执行部门按支出数量排序,依次为企业、研究与开发机构、高等学校;（2）中国科技研发经费投入不断增加;国家财政科技拨款占公共支出的比例递减,但近年来稳定在4%左右;R&D经费投入强度逐年递增,且已超过一些发达国家;（3）虽然基础研究在R&D内部支出中所占比例最低,但科技经费的管理方开始越发重视基础学科;（4）科技专项计划类型的资助面向关乎国计民生的重要现实需求,说明中国科技研发经费体系兼顾基础研究和现实问题。