基于网络的智能辅导模式研究与系统设计

针对目前辅导行业的现状,为解决课后辅导的自动化、实时化的问题,分析了学生课后学习掌握知识的过程,提出了一个基于学生课后学习规律的辅导模型,建立了面向问题的多层面知识辅导新模式,构建了基于此模式的网络智能家教系统的框架结构。该系统采用基于知识的自动推理技术使得推理过程得以完整保存来分析后续的多层面辅导信息,采用资源模型分解知识粒度保证抽象度,采用网络服务模式满足用户的实时使用。以学生提出的几何问题为实例,展示了多层面辅导过程,实验结果表明了该模式和系统设计的可行性。     

Performance Analysis of Gradient Neural Network Exploited for Online Time-Varying Matrix Inversion

This technical note presents theoretical analysis and simulation results on the performance of a classic gradient neural network (GNN), which was designed originally for constant matrix inversion but is now exploited for time-varying matrix inversion. Compared to the constant matrix-inversion case, the gradient neural network inverting a time-varying matrix could only approximately approach its time-varying theoretical inverse, instead of converging exactly. In other words, the steady-state error between the GNN solution and the theoretical/exact inverse does not vanish to zero. In this technical note, the upper bound of such an error is estimated firstly. The global exponential convergence rate is then analyzed for such a Hopfield-type neural network when approaching the bound error. Computer-simulation results finally substantiate the performance analysis of this gradient neural network exploited to invert online time-varying matrices.     

一种用于入侵检测的改进人工免疫算法

通过对基于信息熵和基于欧氏距离的免疫算法的分析和改进,提出一种新的适用于入侵检测的人工免疫算法（AIAID）。该算法引入马氏距离的思想,改进相似度和期望繁殖率的计算,把抗体不同特征的重要性和取值范围加入到相关运算中,对算法流程进行优化。设计一种新的基于AIAID的入侵检测系统模型。实验表明,将AIAID用于入侵检测能够明显缩短训练时间,提高检测效率。     

分辨矩阵法耗时推算

针对粗集理论的分辨矩阵方法求解知识约简过程中时空性能上存在的问题,提出分辨矩阵法耗时推算的原理和算法,包括2个耗时段的推算及推算结果的可靠性验证。推算可预知分辨矩阵法处理数据所消耗的时间,对数据挖掘实验的可行性进行预测。     

Continuous-variable quantum homomorphic signature

Quantum cryptography is believed to be unconditionally secure because its security is ensured by physical laws rather than computational complexity. According to spectrum characteristic, quantum information can be classified into two categories, namely discrete variables and continuous variables. Continuous-variable quantum protocols have gained much attention for their ability to transmit more information with lower cost. To verify the identities of different data sources in a quantum network, we propose a continuous-variable quantum homomorphic signature scheme. It is based on continuous-variable entanglement swapping and provides additive and subtractive homomorphism. Security analysis shows the proposed scheme is secure against replay, forgery and repudiation. Even under nonideal conditions, it supports effective verification within a certain verification threshold.     

医院超声图象管理系统的设计与实现

介绍了医院超声图象管理系统的功能和特点,并阐述了其关键技术。     

一种低压低功耗共源共栅带隙基准电压源的实现

提出了一种低压低功耗的带隙基准电压源电路,设计基于0.5μm2P3M BiCMOS Process,并使用了低压共源共栅电流镜结构减少了对电源电压的依赖,消除了精度与余度之间的矛盾,并用HL50S-S3.1S.lib库文件用HSPICE进行了仿真,其电源抑制比PSRR大约为-78.9dB。     

太湖流域水灾害应急对策研究

太湖流域是我国经济社会高度发达的地区之一,发生水灾害时往往会造成重大经济损失。对发生各类水灾害时的应急对策展开研究总结,以减轻水灾害,避免人员伤亡,保障经济社会可持续健康稳定发展,并通过分析典型案例的实际应对过程,为今后开展类似工作提供参考。     

Repeated Price Search

Consumers check few sites in online purchases. Previous research and experiments we perform demonstrate that consumers can not calculate the optimal strategy for price search. They use heuristics whose performance is better than random and less than optimal. To investigate online price search performance we survey student online textbook purchases. Students achieve good performance because they start with a good strategy and online market organization of marketplace and meta-search sites. An important factor is that algorithms at sites searched perform calculations that reduce the computational complexity of the search.