Reconstructing the Nonlinear Dynamical Systems by Evolutionary Computation Techniques     

LIU Minzhong KANG Lisha 《武汉大学学报：自然科学英文版》2006,11(3):520-524

We introduce a new dynamical evolutionary algorithm（DEA） based on the theory of statistical mechanics and investigate the reconstruction problem for the nonlinear dynamical systems using observation data. The convergence of the algorithm is discussed. We make the numerical experiments and test our model using the two famous chaotic systems （mainly the Lorenz and Chen systems）. The results show the relatively accurate reconstruction of these chaotic systems based on observational data can be obtained. Therefore we may conclude that there are broad prospects using our method to model the nonlinear dynamical systems.  相似文献   

A New Algorithm for On-Line Handwriting Signature Verification Based on Evolutionary Computation   总被引：6，自引：0，他引：6  

ZHENG Jianbin ZHU Guangxi 《武汉大学学报：自然科学英文版》2006,11(3):596-600

The paper proposes an on-line signature verification algorithm, through which test sample and template signatures can be optimizedly matched, based on evolutionary computation （EC）. Firstly, the similarity of signature curve segment is defined, and shift and scale transforms are also introduced due to the randoness of on-line signature. Secondly, this paper puts forward signature verification matching algorithm after establishment of the mathematical model. Thirdly, the concrete realization of the algorithm based on EC is discussed as well. In addition, the influence of shift and scale on the matching result is fully considered in the algorithm. Finally, a computation example is given, and the matching results between the test sample curve and the template signature curve are analyzed in detail, The preliminary experiments reveal that the type of signature verification problem can be solved by EC.  相似文献   

Residential environment index system and evaluation model established by subjective and objective methods   总被引：5，自引：0，他引：5  

Ge J  Hokao K 《浙江大学学报(自然科学英文版)》2004,5(9):1028-1034

In this research, the residential environment index system and evaluation model were established by means of subjective and objective methods. The methodology for establishing the evaluation system for residential environment was first analyzed; then the subjective evaluation data-base was established by questionnaire survey; and at the same time, the objective evaluation data-base was constructed by Geographic Information System (GIS); and then the related equation system between subjective and objective system was developed by multiple regression analysis. This research could benefit evaluation of the residential environment quality for various purposes, and also provide important rudimentary data-base for the development and improvement of residential environment for officials. Furthermore, the index system and evaluation model established in this research could construct a strong relation between subjective evaluation and objective data; and thus could provide a comprehensive, efficient and effective methodology for the evaluation of residential environment.  相似文献   

Ultrastructure of spermatozoa of Bullacta exarata （philippi） and its significance on reproductive evolution and physio-ecological adaptation     

Ying XP  Yang WX  Jiang NC  Zhang YP 《浙江大学学报(自然科学英文版)》2004,5(10):1211-1217

The morphology and ultrastructure of Bullacta exarata spermatozoa observed by light and transmission electron microscopy are presented in this paper. The spermatozoon is composed of head with a simple acrosomal complex and an elongated nucleus, and tail with a midpiece, principal piece and an end piece. The midpiece consists of a mitochondrial ring, and the principal piece is composed of axoneme and lateral fin. The structure of B. exarata spermatozoa differs significantly from that of other gastropods, especially in the lateral fin and the principal piece, which was described scarcely before. A comparison is made between B. exarata and other gastropods, and its significance on reproductive evolution and physio-ecological adaptation is preliminarily discussed.  相似文献   

Pollen record from red clay sequence in the central Loess Plateau between 8.10 and 2.60 Ma   总被引：5，自引：1，他引：4  

MA Yuzhen WU Fuli FANG Xiaomin LI Jijun AN Zhisheng WANG Wei 《科学通报(英文版)》2005,50(19):2234-2243

The origin and development of Asian monsoon circula-tion, the desertification and aridification of Asian inland in relation to vegetation evolution and the soil erosion in northwest China have been more and more drawing inten-sive scientific and society attention. Recently the studiesof monsoon evolution from some Tertiary Red Clay sec-tions located at the central Loess Plateau in the eastern Liupan Mountains, based on chronology, dust flux, grains size, magnetic susceptibility, and rates o…  相似文献   

Investigation on Relationship between Cost and Software Reliability   总被引：1，自引：0，他引：1  

XURen-zuo HANYi-fan HUANGCan YAOJun-feng 《武汉大学学报：自然科学英文版》2005,10(1):9-12

Based on the fact that the software development cost is an important factor to control the whole project, we discuss the relationship between the software development cost and software reliability according to the empirical data collected from the development process. By evolutionary modeling we get an empirical model of the relationship between cost and software reliability, and validate the estimate results with the empirical data.  相似文献   

Evolutionary Design of Boolean Functions     

WANGZhang-yi ZHANGHuan-guo QINZhong-ping MENGQing-shu 《武汉大学学报：自然科学英文版》2005,10(1):179-182

We use evolutionary computing to synthesize Boolean functions randomly. By using specific crossover and mutation operator in evolving process and modifying search space and fitness function, we get some high non-linearity functions which have other good cryptography characteristics such as autocorrelation etc. Comparing to other heuristic search techniques, evolutionary computing approach is more effective because of global search strategy and implicit parallelism.  相似文献   

Evolvable Hardware Based Software-Hardware Co-Designing Platform ECDP     

TU Hang WU Tao-jun LI Yuan-xiang 《武汉大学学报：自然科学英文版》2005,10(6):977-982

Based on the theories of EA （Evolutionary Algorithm） and EHW （Evolvable Hardware）, we devise an EHW based software-hardware co designing platform ECDP, on which we provided standards for hardware system encoding and evolving operation designing, as well as circuit emulating tools. The major features of this system are： two layer-encoding of circuit structure, off-line evolving with software cmulation and the evolving of genetic program designing. With this system, we implemented the auto designing of sonic software-hardware systems, like the random number generator.  相似文献   

用体外定向进化的方法对EPSPS合酶基因草苷膦抗性机制的研究     

王劲  徐婧  金丹  杜世章 《四川大学学报(自然科学版)》2007,44(1):155-159

为了寻找EPSP合酶中某些与草苷膦抗性相关的位点，利用体外定向进化技术，对可变盐单胞菌HT7的EPSP合酶基因，荧光假单胞菌G2的EPSP合酶基因以及按植物偏爱密码子合成G2的EPSP合酶基因，进行DNA shuffling，通过EPSP合酶缺陷型菌株E.coil ER2799的功能互补筛选，获得了7个草苷膦抗性有较大变化的EPSP合酶突变体.  相似文献   

同工酶在梨属系统发育分析中的应用   总被引：2，自引：0，他引：2  

马兵钢  牛建新  冯建荣  刘艳  覃伟铭 《石河子大学学报》2003,7(2):119-123

对新疆梨属的26份样本用POD和EST同工酶电泳，共产生23条带，Nei相似系数为0．316～1．000。构建UPG-MA、NJ树，对西洋梨系统、砂梨系统及部分秋子梨系统内品种能较好地确定其位置，对新疆梨系统、白梨系统、部分秋子梨系统品种及香梨的位置较难确定，且各系统之间相似系数亦较高，bootstrap支持率较低。  相似文献