电子商务与展览业联手──新世纪的完美组合

随着网络经济的发展，电子商务在新经济舞台上扮演着越来越重要的角色，它必将对我国的朝阳产业——展览业产生重大影响。电子商务就是信息流的数字化、电子化，它最拿手的就是对信息和数据的快速传递、交换和处理，促进交流，增加信息透明度，降低交易成本，而展览在其本质意义上说首要功能是传播信息。因此，电子商务与展览业一拍即合，展览业成为电子商务可大显身手的舞台，从而加速我国展览业与国际接轨

计算机信息检索(IR)在药学方面的应用

介绍信息检索产生的背景以及信息检索的分类和方法,分析计算机信息检索在药学应用方面迅速发展的原因,比较计算机检索和手工检索的关系,得出药学信息检索最快速、最合理的方法是以计算机检索为主和手工检索为辅,两种方法结合起来使用

An Improved Algor ithm of K- means

摘要: K- means 算法是最常用的聚类算法之一, 有很多的优点, 但也存在着不足。它不仅对样本的输入顺序敏感, 可能产 生局部最优解, 而且受孤立点的影响很大。文章正是针对这些不足, 提出了一种改进的K- means 算法, 主要从数据预处 理、初始聚类中心的选择方面进行了改进, 并做了改进前后算法的对比实验。结果表明, 改进后的算法不但更具稳定性, 准 确度也高, 受孤立点的影响也大大降低。英文摘要：Abstr act:K- means algorithm is one of the most widespread methods in clustering, including both strong points and also shortages. Not only is it sensitive to the order of sample data, but also it may make out the local excellent and be affected by the outliers. Given these shortages, an improved algorithm is discussed, which makes improvements in data preprocessing and selection of original clustering center. Check experiment was done, which indicates the improved one is more stable, more accurate and the affection by the outliers is down to a much low figure

前移回归分析法在广西省经济预测中的应用

经济指标是多项相关因素的函数,一个时间段内各项指标(自变量)值会影响下一时间段待预测指标(因变量)的取值。本文以广西省12项主要经济指标为实例,采用前移回归方法预测了人均gdP,进而预测了其余指标2008--2009年的取值。这种方法克服了以往时间序列预测只是自身拓展而不考虑多项因素(变量)的不足,也弥补了回归分析预测法必须已知同时期各个自变量值才能预测的缺陷,取得较好的效果。福建省自然科学基金计划资助项目(2006J0407

氨燃料缓解能源安全及替代天然气的可行性分析

文章主要针对我国面临的能源安全问题及现阶段出现的北方地区\"气荒\"现象,结合氨燃料储能密度高、燃烧清洁、热值较高、易储存运输、产业基础完善、用处广泛的特点以及厦门大学的锅炉及发电机掺氨燃烧运行成功的实验结果,定量分析氨燃料可缓解能源安全问题的程度及解决\"气荒\"问题的规模与容量。分析结果表明:引入氨能源体系可以有效优化中国的能源结构,改善过度依赖能源进口的现状,解决天然气短缺的问题。福建省闽江学者经费项目(X170300101);;\n厦门大学能源学院-金融昌氨能源及动力联合研发中心经费项目(0290K8110075

Spectroscopic Characterization on Interaction of Gold (Au ~(3+)) Biosorption by Bacillus megaterium D01

对休眠的巨大芽孢杆菌 (Bacillusmegatherium)D0 1菌体吸附Au3 + 的作用过程进行了谱学表征 .运用AAS考察了pH、时间和温度对D0 1菌体吸附Au3 + 过程的化学动力学和热力学相关参数的影响 .D0 1菌粉中硫元素含量的EDX分析说明该菌体中对Au3 + 具有还原作用的L 半胱氨酸和蛋氨酸的含量极少 ;D0 1菌体水解后葡萄糖含量的UV vis测定说明该菌体水解产物中含有一定量的还原糖 .空白的和吸附Au3 + 的D0 1菌体的FTIR检测表明该菌体细胞壁肽聚糖层糖类化合物的羟基和肽链侧链氨基酸残基离子化羧基为吸附Au3 + 的活性基团 ;肽聚糖层部分多糖的水解产物低聚糖、二糖及单糖等还原糖的半缩醛羟基游离态醛基为电子供体 ,将Au3 + 原位还原成Au0 .葡萄糖和Au3 + 相互作用的XRD和FTIR表征证明Au3 + 是在还原糖的醛基上直接被还原成Au0Biosorptive interaction of gold with resting cell of Bacillus megatherium D01 biomass has been characterized by spectroscopic techniques. The effects of pH, time and temperature on the correlation parameters of chemical kinetics and thermodynamics of the binding reaction has been investigated through the determination of the gold ion binding to the biomass using atomic absorption spectrophotometry (AAS). The analysis for sulfur content in dry powder of the D01 biomass by energy dispersive X-ray (EDX) shows that cysteine and methionine being capable of reducing Au 3+ to Au0 is very small, whereas the glucose content in hydrolysates of the biomass analyzed by ultraviolet-visible spectrophotometry (UV-vis) indicates that the amount of the reducing sugars in the biomass is much larger than 3.33%. The Fourier transform infrared (FTIR) spectroscopy on blank and gold-loaded biomass demonstrates that the active groups such as the hydroxyl group of saccharides and the ionized carboxyl group of amino acid residues on the cell wall seem to be the sites for Au 3+ binding, and the free aldehyde group of the hemiacetalic hydroxyl group from reducing sugars, i.e. the hydrolysates of the polysaccharides, serving as the electron donor, in situ reduces the Au 3+ to Au0. X-ray powder diffractometry (XRD) and FTIR spectroscopic characterizations of the interaction of Au 3+ with glucose confirm that the reduction of Au 3+ to Au0 can directly occur in the aldehyde group of the reducing sugars

Preventive effect and mechanisms of 3,3-diindolylmethane on oxidative stress induced by hydrogen peroxide in HaCaT cells

目的:探究3,3'-二吲哚甲烷(dIM)对过氧化氢(H_2O_2)诱导人角质形成细胞(HACAT)氧化应激作用的预防效应及可能机制。方法:体外培养HACAT细胞,用H_2O_2建立氧化应激模型。采用CCk-8法检测不同浓度(1~20μMOl/l)dIM对HACAT细胞生长的抑制作用;流式细胞术检测dIM作用前后细胞内活性氧自由基(rOS)含量的变化;WESTErn blOT检测不同浓度dIM(0、5、10μMOl/l)对HACAT氧化应激相关蛋白核因子(nf-κb)和丝裂原活化蛋白激酶(MAPkS)磷酸化表达水平的影响。结果:成功建立了HACAT氧化应激模型。CCk-8法研究结果显示1-10μMOl/l dIM对HACAT细胞无明显毒性作用(P>0.05);流式细胞术检测结果表明10μMOl/l dIM预处理可有效预防由H_2O_2诱导的HACAT内rOS产生(P0.05).Flow cytometry results indicated that pretreatment with DIM(10 μmol/L) could inhibit the level of intracellular ROS(P<0.05).With increasing concentration of DIM,the levels of p-p38-MAPK,p-JNK and p-NF-κB were significantly depressed.CONCLUSION:DIM could protect HaCaT cells from H_2O_2-induced oxidative stress via suppressing production of ROS levels and down-regulating the expression of NF-κB and members of MAPKs.DIM might be used as an effective drug to treat or reduce oxidative stressmediated injury in skin cells.国家自然科学基金青年基金(81101562); 广东省科技计划项目(2012B060300005); 广东省自然科学基金(S2012010009633

Design and implementation of distributed system of computerapplication ability test

传统的基于“集中式”的计算机应用水平考试系统存在诸多弊端,如过分依赖中心服务器、造成服务器的负载过大以及系统的扩展性和安全性差。同时,传统的集中控制模式使得系统的维护变得复杂和困难。介绍了分布式计算机应用水平考试系统的软件结构,描述了系统实现过程中的主要技术,对基于网络的考试系统的安全性、主观题阅卷系统的智能化设计进行了详细论述。Traditional testing systems of computer application ability test based on centralized-control have some shortcomings. The host server burdens all the functions of the testing system, which causes the poor expansibility and security of testing systems. And the traditional pattern makes the maintenance of testing systems difficult and complex. This paper introduced the structure of distributed system of computer application ability test, and described the main techniques in the course of realization, and at the same time gives a discussion about the security of the computer testing system based on network and the intelligent design of marking system of the subjectivity exam questions

Lotus and It's Application in the E-government with Domino as Performance Monitor of Web Application

本文提出一种依托lotusdomino强大的安全性和开放性优势,来建构web性能监视器的方法,从而解决系统在工作时对其性能的监测和优化问题.This article suggests a new method of building Web performance invigilator,which rely on the great security and opening of lotus domino.This method can solve the problem of invigilating and optimizing the working system

CPU仿真器结构分析及其IU模块的设计实现

CPU仿真器是进行硬件设计评估,系统软件设计开发和计算机体系结构研究的有力工具。在CPU的研制阶段通常也要同时进行操作系统的开发,为了在新型CPU问世之前运行和调试目标操作系统,就必须开发支持操作系统功能的CPU仿真器。因此,CPU仿真器在嵌入式系统的开发中扮演了重要的角色。本文详细分析了CPU仿真器的结构以及其核心模块IU(Instruction Unit)部分的实现