Remote Sensing Image Enhancement Based on Orthogonal Wavelet Transformation and Pseudo-color Image Processing

针对基于正交小波分析的图像增强技术一般只适用于黑白图像;而伪彩色处理技术不能够充分处理图像中某些细节信息的缺陷,提出了基于正交小波分析和伪彩色的遥感图像增强处理方法;实验结果表明,增强后的遥感图像无论在视觉效果上还是在噪声特性上都有了很大的改善;该方法简便易行且计算量小,在应用中有较大的灵活性;该方法还具有运算速度快和可操作性强等特点,在遥感图像增强研究方面具有广泛的应用前景。Image enhancement technique based on wavelet analysis is only applicable to black-and-white image,and pseudo-color image processing technology can not adequately deal with some of the details information of the image.In this paper,enhancement approach of remote sensing image based on orthogonal wavelet analysis and pseudo-color image processing is put forward.Enhanced remote sensing image have been greatly improved in both visual effects and noise characteristics.The method is simple to implement,and need less calculation,and its application is more flexible.This method also has the characteristics of faster computing speed and operating feasibly and so on.It has broad application prospects in research of remote sensing image enhancement.国家自然科学基金项目(60873179);广西教育厅科研项目(200707LX196

强制医保制度下无保险人群的健康状况研究

因为就业单位不缴或欠缴医疗保险费而被迫无法纳入医疗保险体系的城镇职工在本文中被称为“医保夹心层”。据估算，我国目前存在上千万的医保夹心层人群。本文利用国务院关于城镇居民基本医疗保险试点评估调查2007－2009年的跟踪调查微观数据，研究了医保夹心层的健康及其医疗服务利用情况。我们发现，在控制了个人特征、就业状况、保险状态以及家庭经济状况后，医保夹心层职工的健康状况较差；其无保险状态会直接影响医疗服务利用，表现为医保夹心层更少接受住院服务（但在门诊服务方面没有差别），但一旦住院，夹心层住院花费及其负担都会更重；其次，医疗保险状态还会影响健康意识，表现为夹心层人群在了解医疗保健知识、定期身体健康检查方面缺乏积极性。本文发表在《经济研究》2013年第7期，118-131

Design of Carrier Synchronization Based on Costas Loop

介绍了平方变换法相干解调原理,从工程角度完善了载波提取的电路结构,消除了频移载波的误锁问题.提出用科斯塔斯环法来实现从2dPSk信号中提取相干载波,解决了提取的载波信号存在180度的相位含糊问题,为通信系统提高抗噪性能提供了条件.当载波频率很高时,工作频率较低的科斯塔斯环易于实现.并用SIMulInk设计出科斯塔斯环法提取载波的仿真电路图和进行相应的仿真实验.Theory of coherent demodulation based on method of square counterchange is introduced in this article.The structure of circuit for carrier recovery is perfected in engineering,and the problem of error-lock for frequency-shift carrier is eliminated.Costas Loop is put forward to achieve coherent carrier from 2DPSK signal in this article.The 180° phase's inexplicit problem which exist in carrier recovery is resolved.It improves the resisting noise property of communication system.When carrier frequency is higher,Costas loop is easy to implement carrier synchronization.Because the operating frequency of Costas loop is lower than square PLL.We scheme out emulational circuit diagram for carrier distilling with Costas loop by using simulink and process corresponding emulational experiment.国家自然科学基金项目(60873179);广西教育厅科研项目(200707LX196

High efficient and secure group key management scheme based on optimized GDH

针对gdH(grOuP dIffIE-HEllMAn)方案中节点可能成为系统的瓶颈以及计算复杂度、通信代价和存储复杂度远高于某些集中式方案等缺陷,提出并实现了一种基于优化gdH协商的高效安全的动态群组密钥管理方案,并对其安全性进行了证明。通过对计算量和通信量进行分析比较表明,优化gdH协商协议具有很大的优势,并且能够快速产生或更新组密钥,具有很强的实用性。There are some defects in GDH(group diffie-hellman) scheme,such as the node that may become the bottleneck of the system,and the computational complexity,cost of communications and storage complexity that are much higher than some centralized group key management program.An efficient and secure dynamic group key management scheme based on optimized GDH is proposed and implemented and its security is proven.The optimized GDH consensus agreement has great advantage than GDH by comparing and analysing the volume of calculating and traffic.At the same time,the optimized GDH consensus agreement can quickly produce and update group key,and it owns highly practicability.国家自然科学基金资助项目(60873179);广西教育厅科研资助项目(200707LX196

A quickly-speed running watermarking algorithm based on quantum evolutionary algorithm

针对传统基于人类视觉系统特性的空间域与变换域相结合的水印算法中嵌入信息量小、嵌入位置定位及检测准确率低和算法运行速度慢等缺陷,提出并实现一种基于量子进化算法(QEA)的快速水印新算法。仿真实验结果表明,新算法不仅生成水印图像的速度快,而且对各种攻击具有良好的敏感性和鲁棒性。新算法在应用中有较大的灵活性,并且具有可嵌入信息容量大、运算速度快和可操作性强等特点。There are limitations such as smaller embedded information capacity,lower accurate rate for positioning embedded location and detection and slower running speed in traditional watermarking algorithm which combines spatial domain and transform domain based on characteristics of human visual system.A quickly-speed running watermarking algorithm based on quantum evolutionary algorithm is proposed and implemented.The simulation results show that the proposed algorithm owns not only faster watermark image generation,but also have good sensitivity and robustness for all kinds of attacks.The proposed algorithm is more flexible in application,and it can embed more information and improve the computing speed.The method can be easily operated.国家自然科学基金资助项目(60873179);广西教育厅科研资助项目(200707LX196

基于状态方面的Web服务动态替换

随着面向服务计算技术的成熟,服务复合已成为Internet上开发企业间业务协作的一种新模式,WS-BPEL是服务复合事实上的标准。但是由于复合服务所依赖的第三方伙伴服务的分布、自治和松散耦合等特性,在执行过程中易受到伙伴服务失效的影响,可靠性无法得到保证,因此需要支持在运行时对伙伴服务进行动态替换。目前的BPEL规范只提供有限的服务替换功能,当与伙伴服务的交互涉及到一系列有状态的会话操作时,服务替换就更加复杂。通过对面向方面的研究,提出面向BFEL语言的状态方面扩展。通过状态方面,记录与伙伴服务交互过程中中国计算机学

Preparation of silicon nitride fibers by pyrolysis nitridation of polycarbosilance

将PCS电子束交联丝在氨气氛中氮化热解、脱碳氨化,继在氮气氛中高温热引发缩合/转氨基反应,生成硅氮烷并最终形成氮化硅(SI3n4)纤维。所制备的SI3n4纤维白色透明,横截面和表面均光滑致密,无明显缺陷和孔洞。还研究了氮化热解的反应机理以及热解工艺对氮化硅(SI3n4)纤维结构和性能的影响。红外光谱和元素分析的结果显示,氮化热解脱碳彻底,SI3n4纤维C含量<1%;烧结温度提高,n含量随之增加,O含量则先增后减;烧结温度不超过1500℃,纤维为无定型。力学性能结果分析表明,随热解温度的提高,纤维力学性能先提后降,1300℃时达到最大值。氮化热解过程是采用nH3进行脱碳氨化,并在n2气氛下高温热引发缩合/转氨基反应产生硅氮烷并最终形成SI3n4的过程。In this work,PCS cured fibers were pyrolysis nitridation in the ammonia atmosphere for carbon removal and amination,and then condensation/nitridation reaction at high temperature in the nitrogen to produce Si3 N4 fibers.Results showed that as-prepared Si3 N4 fibers were colorless and transparent.What was more,the skin of the fiber was smooth and the cross section was rather dense without identifiable defects.This paper also discussed the mechanism of nitridation and the influence of pyrolysis conditions on the structure and properties of Si3 N4 fibers.The results of FT-IR spectra and elemental analysis showed that the carbon content was extremely low after amination and pyrolysis,which was less than 1%,while the nitrogen content increased with the elevated pyrolysis temperature,and the oxygen content first increased and then decreased with the elevated pyrolysis temperature.The fibers were amorphous when the pyrolysis temperature was less than 1500℃,while the tensile strength reached a maximum at 1300℃.The processes of pyrolysis nitridation were a process of decarburization and ammonification,and then condensation/nitridation at high temperature in the nitrogen,finally producing Si3N4fibers.国家自然科学基金面上资助项目(51002127;51072169