等离子体表面氮掺杂对非晶碳膜场发射特性的影响.doc

第4期不完备信息系统中Rough集的扩充模型尹旭日 商 琳 （337）定义可计算函数时不动点算子的不必要性戴静安 宋方敏 （342）等离子体表面氮掺杂对非晶碳膜场发射特性的影响 李 伟 岑展鸿 钱 波 梅嘉欣 徐 骏 陈坤基 （346）自动指纹识别系统预处理技术及细节特征提取算法的研究杨小冬 宁新宝 尹义龙 （351）一款基于新型Field Programmable Gate Array芯片的投影仪梯形校正系统研究与实现曹凤莲 沈庆宏 盛任农 高敦堂 （362）关于支持向量机DirectSVM算法的探讨肇 莹 刘红星 高敦堂 （368）小波域分形编码数字水印的研究李 杨 都思丹 （373）基于球麦克风阵列的三维空间多声源定位林志斌 徐柏龄 （384）润滑脂壁滑移管流测试系统的设计张晓光 张兴敢 孙 正 （395）基于改进模型的网络拥塞控制策略陆锦军 王执铨 （403）多囊卵巢综合征诊断指标与雌激素代谢的关系曲军卫 吴效科 王 勇 侯丽辉 （417）长江大通水文站径流量的时间系列分析张 瑞 汪亚平 潘少明 （423）研究简报三种兽药添加剂对赤子爱胜蚓体内纤维素酶和SOD酶的活性影响陈海刚 李兆利 徐 韵 陈营军 孔志明 （435）Extension Model of Rough Set under Incomplete Information Yin Xu-Ri Shang Lin (337)To -define the Computable Functions without the Fixed Point OperatorsDai Jing-An Song Fang-Min (342)The Improvements in Field Electron Emission Characteristics of Amorphous Carbon Films due to Nitrogen Surface DopingLi Wei Cen Zhan-Hong Qian Bo et al (346)Fingerprint Image Preprocessing Technique and Feature Extraction AlgorithmYang Xiao-Dong Ning Xin-Bao Yin Yi-Long （351）Realization of Keystone Correction based on a New Field Programmable Gate Array Chip Cao Feng-Lian Shen Qing-Hong Sheng Ren-Nong et al（362）Investigation on DirectSVM Algorithm for Support Vector MachineZhao Ying Liu Hong-Xing Gao Dun-Tang （368）Digital Watermarking based on Fractal Coding in Wavelet Domain Li Yang Du Si-Dan （373）Three-dimensional Localization of Multiple Acoustic Sources Using Spherical Microphone ArrayLin Zhi-Bin Xu Bo-Ling （384）The Wall-Slip Testing System of Lubrication Grease in Flowing PipeZhang Xiao-Guang Zhang Xing-Gan Sun Zheng（395）Network Congestion Control Strategy based on the Improved ModelLu Jin-Jun Wang Zhi-Quan (403)Estrogen Synthesis and Glucose Metabolism in Women with Polycystic Ovary SyndromeQu Jun-Wei Wu Xiao-Ke Wang Yong et al（417）Analyses with Wavelet and Hilbert-Huang Transform on Monthly Water Discharges at Datong Station, Yangtze River Zhang Rui Wang Ya-Ping Pan Shao-Min （423）NotesCellulase and Superoxide Dismutase Activities in the Earthworm Eisenia foetida Exposed to Three Veterinary Drugs and Additives Chen Hai-Gang Li Zhao-Li Xu Yun et al（435）不完备信息系统中Rough集的扩充模型基金项目：国家自然科学基金（60503022）收稿日期：2005-09-12通讯联系人，E-mail:尹旭日1,商 琳2（1. 解放军汽车管理学院军事交通仿真实验室，蚌埠，233011；2. 南京大学计算机软件新技术国家重点实验室，南京，210093）摘 要: 经典的Rough集理论所处理的信息系统必须是完备的.为了能够分析处理不完备的信息系统，需要建立新的扩充Rough集模型.对现有的几种比较有影响的Rough集扩展模型进行了分析研究，提出了一种带约束的相似关系Rough集模型，并将这些扩充模型之间的关系进行了分析比较.结果显示，基于约束相似关系的扩充Rough集模型优于基于容差关系的扩充Rough集模型和基于相似关系的扩充Rough集模型，使得对象的划分更加合理，符合人们在处理数据时的直观感觉. 关键词: Rough集，不完备信息系统，容差关系，相似关系，约束相似关系中图分类号： TP 18Extension Model of Rough Set under Incomplete InformationYin Xu-Ri1,Shang Lin2(1. Simulation Laboratory of Military Traffic, Institute of Automobile Management of the Peoples Liberation Army, Bengbu, 233011,China;2. National Laboratory for Novel Software Technology, Nanjing University, Nanjing, 210093,China)Abstract: The classical rough set theory is based on complete information systems. The starting point of the rough set theory is an observation that objects with the same description are indiscernible with respect to the available information. It classifies objects using upper and lower-approximation defined on an indiscernibility relation， a kind of equivalent relation. But the indiscernibility relation may be too rigid in some situations. Therefore several generalizations of the rough set theory have been proposed， some of which extend the indiscernibility relation using more general similarity or tolerance relations. Unfortunately, these extensions have their own limitation. In this paper, several extension model of rough set under incomplete information are discussed. A concept of constrained similarity relation as a new extension of rough sets theory is introduced, and the upper-approximation and lower-approximation defined on constrained similarity relation are proposed. Furthermore, the performances of these extended relations are compared also. Analysis result shows that this relation can effectively process incomplete information and generate rational object classes. Key words: rough set, incomplete information system, tolerance relation, similarity relation, constrained similarity relation定义可计算函数时不动点算子的不必要性收稿日期：2005-05-21通讯联系人，E-mail:戴静安，宋方敏（南京大学计算机软件新技术国家重点实验室，南京，210093）摘 要: 演算这种计算模型，是一种良好的数学工具，与递归函数密切相关.-演算中的不动点算子，增强了系统的表达能力，表达了递归函数中递归的性质，但同时也略有不足，因为常见不动点算子，都没有-范式.介绍了一种方法，可以不借助不动点算子，利用Church数字系统的特点，用-范式定义所有可计算函数.关键词: 不动点算子，-范式中图分类号： TN 131To -define the Computable Functions without the Fixed Point OperatorsDai Jing-An, Song Fang-Min(State Key Laboratry for Novel Software Technology, Nanjing University, Nanjing, 210093,China)Abstract: -Calculus is a model of computation. It is related with Recursive function, another model of computation. There are fixed point combinators in -Calculus expressing the recursive nature in Recursive function. However, as the fixed point combinators such as Y,have no -Normal Forms, most terms defining recusive functions by using fixed point combinators have no -Normal Forms. This paper introduces a method that can define all the computable functions by using -Normal Forms, without the fixed point combinators. It is based on the particularity of the Churchs numeral system, where the recursive nature is hidden inherently. A problem is how to keep combinations of -Normal Forms -defining functions that still have -Normal Forms, as it is necessary to -define sets of computable functions.Key words: fixed point combinators, -Normal Form等离子体表面氮掺杂对非晶碳膜场发射特性的影响基金项目：国家自然科学基金(50472066, 90301009)，国家重点基础研究发展规划(973)项目(2001CB610503)收稿日期：2006-02-12通讯联系人，E-mail:李 伟，岑展鸿，钱 波，梅嘉欣，徐 骏，陈坤基（南京大学物理系, 固体微结构物理国家重点实验室, 南京，210093）摘 要: 氢化非晶碳膜作为一种场致阴极电子发射材料已被广泛研究，通过对薄膜进行掺杂以提高其场发射特性已被证明是行之有效的方法之一. 利用常规等离子体化学气相淀积技术制备了氢化非晶碳薄膜材料，在原位利用氮等离子体对碳膜表面进行N型掺杂.通过不同手段研究了氮表面掺杂前后非晶碳膜的微结构和化学键的变化，对表面掺杂前后的薄膜的场电子特性的测量表明，在氮表面掺杂后其场电子发射特性有了明显改善，特别是场发射的阈值电场从掺杂前的3.2 V/m下降到掺杂后的1.0 V/m.初步实验分析表明：由于氮表面掺杂后，在碳膜表面形成N-H键，从而导致碳膜表面的有效功函数降低使场电子发射特性得以提高.关键词: 场发射, 氢化非晶碳, 表面掺杂中图分类号： TN 412The Improvements in Field Electron Emission Characteristics of Amorphous Carbon Films due to Nitrogen Surface DopingLi Wei, Cen Zhan-Hong, Qian Bo, Mei Jia-Xin, Xu Jun, Chen Kun-Ji(National Laboratory of Solid State Microstructures, Department of Physics, Nanjing University, Nanjing, 210093, China)Abstract: Hydrogenated amorphous carbon films have been widely investigated as one of cathode field emission materials. It has been recognized that the film microstructures, surface chemical compositions and even the film thickness can strongly influence the electron emission characteristics from amorphous carbon materials. By using Ar, H and O2 plasma to treat amorphous carbon film surface, the field emission characteristics can be modified obviously due to the modification of the film surface configurations and morphology. It has been verified that doping of nitrogen in the films is one of the effective ways to improve the field emission characteristics. In this paper, we prepared hydrogenated amorphous carbon films in conventional r.f. plasma enhanced chemical vapor deposition (PECVD) system at low substrate temperature and performed N type in situ doping on the surface of carbon films by nitrogen plasma surface treatments. The change of the surface structures and bonding configurations were investigated by different measurements techniques for samples with and without nitrogen surface doping. The field electron emission characteristics of the films before and after nitrogen surface doping were studied and it is shown that the field emission properties had been improved obviously, especially the threshold electric field for electron emission which is defined as the electric field at the emission current density of 10-6 A/cm2. The threshold electric field is reduced from 3.2 V/m to 1.0 V/m after nitrogen surface doping. Preliminarily analysis showed that the improvement of field emission properties can be attributed to the decrease of the effective work function of the front surface of amorphous carbon film due to the formation of N-related states on the surface after nitrogen plasma surface doping.Key words: field emission, amorphous hydrogenated carbon, surface doping自动指纹识别系统预处理技术及细节特征提取算法的研究基金项目：南京大学重大应用研究预研项目(2001-03)收稿日期：2005-12-15通讯联系人，E-mail:杨小冬，宁新宝，尹义龙（南京大学电子科学与工程系，生物医学电子工程研究所，南京，210093）摘 要: 指纹图像预处理是自动指纹识别系统(AFIS)的关键步骤，它的好坏直接影响到整个系统的速度和准确率. 详细介绍了预处理过程中指纹图像与背景分离、方向信息提取、纹线提取、二值化、细化，以及细节特征提取等关键技术.在这些模块中，提出了一些改进算法和新的思想.根据人指纹本身是一个曲面结构的特点，采用一种自适应的局部阈值分离方法，解决处于不同深浅区域的指纹图像均能有效地同背景分离；提出了一种改进的、基于非彻底细化图像的细节特征提取算法，在不对纹线进行任何处理的情况下，直接从细化指纹图像上提取原始细节特征点集合，并针对各种噪声产生的伪特征点进行修复；另外，还介绍了一种基于灰度纹线跟踪直接提取指纹图像细节特征的新方法，并与传统算法进行了比较.这种方法不经过二值化、细化等过程，能显著减少预处理带来的累计误差，加快处理速度，在一定程度上提高了准确率.实验证明，以上算法行之有效，在实际应用和严格测验中取得了较好的效果.关键词: 指纹预处理，细节特征提取，纹线跟踪中图分类号： TP 391Fingerprint Image Preprocessing Technique and Feature Extraction AlgorithmYang Xiao-Dong , Ning Xin-Bao, Yin Yi-Long(Department of Electronic Science and Engineering,Institute of Biomedical Electronic Engineering, Nanjing University, Nanjing, 210093,China)Abstract: The biologic identification technology that is delegated by fingerprint has widely developed in recent years. It is recognized to bring a revolution in identification area. The study of fingerprint has high academic vague as well as social benefit, and is becoming one of the research hotspots in many countries. Of the whole Automatic Fingerprint Identification System(AFIS), fingerprint image preprocessing is the core and key step. The input fingerprint image should be preprocessed first before feature extraction and matching can be done afterwards. These processes can influence the speed and accuracy of the entire system. In this paper, we made a deep research on these preprocessing techniques, which included the separation of foreground and background regions, the orientation information extraction, ridge extraction, image enhancement, binarization, image thinning, as well as feature extraction. In these process modules, we brought forward some new algorithms and novel thoughts. Therefore, the AFIS was complemented and perfected in several aspects. According to the characteristic structure that the fingerprint itself is a curving plane, we introduced a separating method using selfadaptive local threshold, which could solve the problems that fingerprint images in areas of different depth could all be separated from background effectively. We also presented an improved non-thorough thinning-image-based feature extraction method. In the premise of not dealing with the ridge anywhere, we extracted the feature points set of the original fingerprints directly from the thinned images. Then, we repaired these feature points by deleting those fake minutiae brought by some sorts of yawp. This algorithm greatly increased the feature extraction speed. The accurate rate was achieved to above eighty seven percent. But when the fingerprint images were of very poor quality, the inherent flaw of this algorithm would delete some true minutiae. In addition, we also introduced a novel feature extraction method, which was based on the following fingerprint ridgelines. The minutiae were directly extracted from the original gray scale fingerprints that had not been preprocessed, such as binarization and thinning etc. Compared with traditional methods, this one could markedly reduce the accumulated errors produced by preprocessing processes. So, the speed was increased and the accurate rate was enhanced to some degree too. In the end of this paper, we tested the performance of this AFIS under NJU-2000 database. The testing items included seven aspects such as Average Enroll Time, Average Match Time, False Rejection Rate, and False Acceptance Rate, etc. Using the FRR as the function of FAR, we drew the Receiver Operating Curve then. The experiment results showed that this system could achieve better results and performance indexes. The preprocessing time by using these improved methods mentioned above was less than that of the traditional algorithms. After testing many fingerprint images of different qualities, we arrive at the conclusions that the FRR is less than two percent, the FAR is less than zero point zero one percent, and the identification time is not more than two seconds. These performance indexes all reach an advanced level. Key words: fingerprint image preprocessing, feature extraction, ridge following一款基于新型Field Programmable Gate Array芯片的投影仪梯形校正系统研究与实现基金项目：南京大学应用开发基金（YY200403）收稿日期：2005-11-01通讯联系人，E-mail:曹凤莲1，沈庆宏1，盛任农2，高敦堂1（1. 南京大学电子科学与工程系，南京，210093；2. 北京电子技术应用研究所，北京，100091）摘 要: 投影设备配备的梯形校正普遍存在校正范围小，画面的一些线条和字符边缘会出现毛刺和不平滑现象，矫正效果不理想. 如果采用通用的图像处理芯片和复杂的算法，可以解决上述问题，但又会导致成本急剧上升. 为了解决上述矛盾，提出一种基于FPGA(Field Programmable Gate Array)芯片的新型梯形校正实现方案，解决了校正范围与锯齿失真的矛盾问题，并为进一步成为芯片级产品铺平了道路. 图像处理采用kaiser窗函数和sinc函数相结合的方法进行插值，这样的滤波器改善了旁瓣抑制，具有较好的通带性能. 介绍了梯形失真的产生和校正原理，提出了利用FPGA芯片XC3S400作为核心图像处理单元的梯形校正系统的硬件和软件实现，说明了该芯片结构、功能及特性，最后提供了校正的效果图. 关键词: 图像处理，梯形校正，Field Programmable Gate Array，锯齿失真中图分类号： TP 274Realization of Keystone Correction based ona New Field Programmable Gate Array ChipCao Feng-Lian1,Shen Qing-Hong1,Sheng Ren-Nong2,Gao Dun-Tang1(1. Department of Electronic Science and Engineering, Nanjing University, Nanjing, 210093, China;2. Beijing Application Institute of Electronic Technology, Beijing, 100091, China)Abstract: Nowadays the keystone correction has become the basic function of a projector. But there are several ubiquitous problems, such as small rectification scope as well as unsmoothed edge of some lines and characters on the screen. Sometimes the calibration result is unacceptable. The above problems can be resolved by adopting universal image processing DSP and a complicated algorithm, the price of which will rise dramatically. In order to avoid this conflict and reduce the cost of the projector, this paper provides a new keystone correction solution based on the FPGA (Field Programmable Gate Array) chip. It solves the problem of rectification scope and jaggy distortion and provides the building block for being a chip class product. The image data is processed by the combination of Kaiser window function and Sinc function. Kaiser window has an adjustable parameter. The parameter controls how steeply it approaches zero at the edges. This kind of filters can relieve side-lobe suppression and has better pass-band capability. This paper introduces the theory about how the keystone distortion comes about and how it can be corrected. It puts forward a method to implement the hardware and software of keystone correction system by using FPGA chip XC3S400 as a kernel of image processing unit. It explains the architecture, function and characteristics of the chip and finally gives the image samples of the correction effect.Key words: image processing, keystone correction, Field Programmable Gate Array, jaggy distortion关于支持向量机DirectSVM算法的探讨基金项目：国家自然科学基金（60275041）收稿日期：2005-12-24通讯联系人，E-mail:肇 莹，刘红星，高敦堂（南京大学电子科学与工程系，南京，210093）摘 要: DirectSVM算法是求解支持向量机的一种简单快速迭代算法，具有最好的几何直观性.算法将线性可分的两类样本中距离最近的两个异类样本点作为支持向量，以该两点连线的垂直平分面作为初始分类超平面，然后根据分类情况逐步确定新的支持向量，即逐步优化出最优分类超平面.对该算法进行了测试，发现该算法具有局限性，并对算法局限性产生的根源进行了分析，对如何合理使用DirectSVM算法进行了讨论.结论是：用DirectSVM算法直接求解最优分类面是不可靠的，但可以作为支持向量机的一种近似算法，也可以作为求解候选支持向量集的方法，再与其他经典算法结合使用.关键词: 支持向量机，直接支持向量机，最优分类面中图分类号： TP 18Investigation on DirectSVM Algorithm for Support Vector MachineZhao Ying, Liu Hong- Xing, Gao Dun-Tang(Department of Electronic Science and Engineering, Nanjing University, Nanjing, 210093, China)Abstract: Support vector machines (SVMs), which are based on the principle of structural risk minimization, are by far the most sophisticated and powerful classifiers available today. Training an SVM classifier is substantially solving a quadratic programming (QP) problem. Among those SVM training algorithms, Sequential Minimal Optimization and Nearest Point Algorithm are of much concern. Platts Sequential Minimal Optimization algorithm is a fast iterative algorithm which divides the large scale QP problem into a series of small scale QP sub-problems, thus overcoming the difficulties of the original QP problem which needs enormous matrix storage and does expensive matrix operations. The NPA algorithm transforms a particular SVM classification formulation into a problem of calculating the nearest training samples between two closed convex polytopes in the hidden feature space formed by the two training sample sets. DirectSVM is a very simple iterative algorithm for constructing support vector machine classifiers, and it is most intuitive geometrically. The DirectSVM algorithm is based on the proposition that the two closest training points of the opposite class in a training set are support vectors. Other support vectors are found by using the following conjecture: the training point that maximally violates the current hyper-plane is also a support vector. Th