基于用户映射的CAS单点登录系统设计与实现

随着信息化进一步发展,企业应用系统越来越多。用户每使用一个系统时都必须登录一次,给用户带来不便,而单点登录机制能很好的解决这一问题。本文介绍一个基于用户映射的单点登录系统的设计与实现,系统采用CAS实现统一用户认证,为用户登录多应用系统提供统一的入口,实现基于LDAP的人员组织架构管理,并通过用户映射机制实现多应用系统的整合。     

MEMS-tunable vertical-cavity SOAs

We present the signal gain, wavelength tuning characteristics, saturation properties, and noise figure (NF) of MEMS-based widely tunable vertical-cavity semiconductor optical amplifiers (VCSOAs) for various optical cavity designs, and we compare the theoretical results to data generated from a number of experimental devices. Using general Fabry-Pe/spl acute/rot relationships, it is possible to model both the wavelength tuning characteristics and the peak signal gain of tunable vertical-cavity amplifiers, while a rate-equation analysis is used to describe the saturation output power and NF as a function of the VCSOA resonant wavelength. Additionally, the basic design principles for an integrated electrostatic actuator are outlined. It is found that MEMS-tunable VCSOAs follow many of the same design trends as fixed-wavelength devices. However, with tunable devices, the effects of varying mirror reflectance and varying single-pass gain associated with the MEMS-based tuning mechanism lead to changing amplifier properties over the wavelength span of the device.     

小型电机的工程设计

在Windows平台上，利用C＋＋Builder可视化、反馈性和调试功能，可供专业工程技术人员学习和掌握简单易学的实践性和应用性强的工程设计，实现小型异步电机的数据分析和处理。形成了比较完善的工程设计软件。     

基于混沌序列的相干OCDMA系统性能分析

文章把二进制的双极性混沌序列应用到两个相干光码分多址(OCDMA)系统中,推导了信噪比和误码率的表达式,仿真分析了误码率随用户数的变化曲线,并和使用Gold序列的同一方案进行了比较,研究结果表明基于混沌序列的系统有较低的误码率和较高的安全性.     

Direction of arrival estimation via reweighted $$l_1$$ norm penalty algorithm for monostatic MIMO radar

In this paper, a reweighted \(l_1\) norm penalty algorithm for direction of arrival (DOA) estimation in monostatic multiple-input multiple-output radar is proposed. In the proposed method, exploiting the inherent multidimensional structure of received data after matched filtering, the singular value decomposition (SVD) technique of the data matrix is employed to reduce the dimension of the received signal. Then a novel weight matrix is designed for reweighting the \(l_1\) norm minimization by exploiting the coefficients of the reduced-dimensional Capon (RD-Capon) spatial spectrum. The proposed algorithm enhances the sparsity of the solution by the reweighted \(l_1\) norm constraint minimization, and the DOAs can be estimated by finding the non-zero rows of the recovered matrix. Owing to utilizing the SVD technique and the novel weight matrix, the proposed algorithm can provide better angle estimation performance than RD-Capon and \(l_1\)-SRACV algorithms. Furthermore, it is suitable for coherent sources and has a low sensitivity to the incorrect determination of the source numbers. The effectiveness and superior performance of the proposed algorithm are demonstrated by numerical simulations.     

Remove key escrow from the BF and Gentry identity-based encryption with non-interactive key generation

Key escrow is inherent in identity based encryption (IBE) since it was first put forward by Shamir. A key generation center (KGC) or private key generator is in charge of generating the user’s secret key, therefore a malicious one can decrypt any ciphertext without being found. This paper introduces a new scheme to eliminate key escrow from IBE. This scheme is based on the security concept of anonymous ciphertext indistinguishability against key generation center (ACI-KGC) which is introduced by Chow. We equip the Boneh and Franklin IBE (BF-IBE) and Gentry-IBE with our scheme and give the security analysis to show the accuracy and the security of it. In contrast to Chow’s scheme, to generate the secret key, our approach does not require the interactive protocol which brings about much extra costs.     

Strong UV intensity enhancement in ZnO nanorods via surface modification of formic acid

The ZnO nanorods arrays synthesized by the chemical bath deposition method were surface modified by the formic acid at room temperature in a very short time. The optical properties of the samples before and after modification had been investigated in detail. The results showed a remarkable strong enhancement of UV emission intensity by almost a factor of 14 after the formic acid modification, which is mainly attributed to the great suppression of the surface recombination since the formic acid can effectively remove a part of OH bonds on the surface of ZnO nanorods.     

NON-PARAMETRIC TOPIC MODEL FOR DISCOVERING GEOGRAPHICAL TOPIC VARIATIONS

This paper presents a non-parametric topic model that captures not only the latent topics in text collections, but also how the topics change over space. Unlike other recent work that relies on either Gaussian assumptions or diseretization of locations, here topics are associated with a distance dependent Chinese Restaurant Process （ddCRP）, and for each document, the observed words are influenced by the document＇s GPS-tag. Our model allows both unbound number and flexible distribution of the geographical variations of the topics＇ content. We develop a Gibbs sampler for the proposal, and compare it with existing models on a real data set basis.     

简易数字存储示波器电子综合实验项目设计

设计了一个电子综合实验项目简易存储示波器,让学生利用低频,数字电路、单片机技术、EDA技术等相关专业技能,完成方案设计,电路制作、直到最后的调试验收整个项目开发过程。培养学生应用已学的专业基础知识,进行项目设计和开发的能力。