Building a highly available and intrusion tolerant database security and protection system (DSPS)

INTRODUCTIONHowtoprotectthedatabase ,thekernelre sourcesofinformationwarfare,isbecomingmoreandmoreimportantsincetherapiddevelopmentofcomputerandcommunicationtechnology .TheArtificialIntelligenceInstituteofZhejiangUni versityhasprototypedaDatabaseSecuritya…     

Mathematical Analysis of Energy Efficiency in IEEE 802.11 DCF

The standardized IEEE ,802. II distributed coordination function （ DCF） provides a contention-based distributed channel access mechanism for mobile stations to share the wireless medium. However, when stations are mobile or portable units, power consumption becomes a primary issue since terminals are usually battery driven. This paper proposes an analytical model that calculates the energy efficiency of both the basic and the RTS/CTS access mechanisms of the IEEE 802. II protocol. The model is validated with simulation results using NS-2 simulation package. The effects of the network size, the average packet length, the initial contention window and maximum backoff stages on the energy efficiency of both access mechanisms are also investigated. Results show that the basic scheme has low energy efficiency at large packet length and large network size, and depends strongly on the number of stations and the backoff procedure parameters. Conversely, the RTS/CTS mechanism provides higher energy efficiency when the network size is large, and is more robust to variations in the backoff procedure parameters.     

浅谈高校合并中财务管理应注意的问题

从当前高等教育改革现状高校合并财务合并是关键，并就如何面对合并，如何解决新问题谈出自己对于加强财务管理的几点看法。     

A novel method for mobile robot simultaneous localization and mapping

INTRODUCTION A key prerequisite for a truly autonomous robot is that it can simultaneously localize itself and accu-rately map its surroundings (Kortenkamp et al., 1998), which is known as Simultaneous Localization and Mapping (SLAM), which, when phrased as a state estimation problem, involves a variable number of dimensions. Murphy and Russell (2001) adopted Rao-Blackwellized particle filters (RBPFs) as an effective way for representing alternative hypotheses on robot paths and ass…     

完善高校成人教育学籍档案管理之我见

分析了高校成人教育学生学籍档案管理的现状,以及建立电子学籍档案的必要性,提出完善学生学籍档案管理工作的途径,以此提高学籍档案的使用效益和教学管理工作。     

阮元教育思想探析

清代著名学者阮元,创办了新式书院诂经精舍和学海堂,旨在培养有"经世致用"、对社会有用的人才.书院提倡德才兼备;主张因材施教,自由探讨;强调实事求是,学以致用;学术研究和教学相结合;确立破旧立新、推举学长的教学体制.倡导了实践,培养了学生的实际能力.阮元的教育思想和实践对清末的教育界产生了深远的影响,为中国的教育事业做出了突出的贡献.     

EBF网络特征映射和恢复及其在鲁棒话者识别中的应用

The performance of speaker verification systems is often compromised under real-world environments. For example, variations in handset characteristics could cause severe performance degradation. This paper presents a novel method to overcome this problem by using a non-linear handset mapper. Under this method, a mapper is constructed by training an elliptical basis function network using distorted speech features as inputs and the corresponding clean features as the desired outputs. During feature recuperation, clean features are recovered by feeding the distorted features to the feature mapper. The recovered features are then presented to a speaker model as if they were derived from clean speech. Experimental evaluations based on 258 speakers of the TIMIT and NTIMIT corpuses suggest that the feature mappers improve the verification performance remarkably.     

以实用教学内容培养高职专业人才--计算机信息管理专业"会计学"课程教改初探

计算机信息管理专业的《会计学》课程从内容上应该吸纳《基础会计》，《财务会计》，《会计模拟实习》几门学科的相关内容，从体系上应该以《基础会计》内容为主线，以《财务会计》内容为核心，以《财务会计》作业作为《会计模拟实习》经济业务内容；在教学方式上应突出直观性教学，并在实践教学环节注重交叉渗透，在考核手手段上集模拟实习作业，笔试，口试于一体，综合评定成绩。并在实践教学环节注重交叉渗透；在考核手段上集模拟实习作业，笔试，口试于一体，综合评定成绩。     

5-溴水杨醛甘氨酸修饰碳糊电极测定微量Cu2+的研究

在pH=9.0 H3BO3-Na2B4O7缓冲体系中,以5-溴水杨醛甘氨酸修饰碳糊电极为工作电极,Cu2 于 120mV(vs.SCE)处产生一灵敏的吸附波,其二阶导数峰电流与Cu2 浓度在4.0×10-9~8.0×10-7mol.dm-3范围内呈良好的线性关系,相关系数为0.9964,检出限为6.0×10-10mol.dm-3(3倍信噪比)。应用该法测定发样中Cu2 的含量,结果令人满意。     

高校信息管理系统的安全关键技术

高校信息管理系统面临的安全威胁问题日趋多样化和复杂化，系统通过统一身份认证、访问控制、数字签名等一系列安全技术设计并实现了实用有效的安全防范机制，为高校信息化办公提供有力的保证。