Fatigue life calculation by means of the cycle counting and spectral methods under multiaxial random loading

The paper contains a new algorithm for estimation of fatigue life in HCF regime under multiaxial random loading using spectral methods. Loading of Gaussian distribution and narrow‐ and broad‐band frequency spectra were assumed. Various characteristic states of multiaxial loading were considered. The equivalent stress history was determined with use of the failure criteria of multiaxial fatigue based on the critical plane. For determination of the critical plane position, the method of variance was applied. During simulation, the authors compared the results obtained by a spectral method in the frequency domain with those from the rain‐flow algorithm in the time domain. The paper also contains the results of fatigue tests for 18G2A structural steel subjected to bending and combined bending with torsion. The tests were performed in order to verify the proposed algorithms for determination of fatigue life. It has been shown that under multiaxial random loading results of fatigue life calculated according to the considered algorithms in frequency and time domains are well correlated with the results of experiments.     

基于离散泰勒级数的新型联想记忆系统

基于离散泰勒级数提出一种对任意阶多维函数可实现无差逼近的新型联想记忆系统，详细讨论了该系统的插值算法、训练规则及寻址机制，新型联想记忆系统相对于CMAC具有逼近精度更高、占用存储单元较少、学习速度较快等优点，该系统在信号处理、模式识别、过程建模及高精度实时智能控制等领域具有广泛的应用价值，仿真实例表明了系统的可行性与有效性。     

遗传-多点退火接力混合算法的应用

遗传-多点退火接力混合算法是先进行遗传算法操作,再接力使用模拟退火法操作的一种尝试。其关键在于遗传算法中变异的处理及退火中初始温度和降温值的处理。给出了该方法的基本过程和原型过程的数学描述,对算法中的罚因子,变异情况及温度值的选取进行了分析。通过具体实例的计算结果表明,将此方法用于非线性约束优化是可行的。     

基于Agent的遗传算法描述与演化模型研究

Agent是指具有智能的人或其它智能物.它具有自治、反响、推测、协作、自学习和相互学习等能力,本文基于Darwin自然进化论与Mendel遗传变异理论,给出Agent的遗传算法与演化模型.这些理论的提出,进一步丰富和完善了Agent的研究内容.     

OSPF路由协议及其实现算法

随着网络规模的不断扩大，路由器在沟通子网连接和实现信息交换方面的重要作用逐渐被人们所认知。介绍了OSPF(Open Shortest Path First)路由协议的特征、实现算法和工作原理等内容。OSPF已成为目前Internet广域网和Itranet企业网采用最多，应用最广泛的路由协议之一。OSPF路由协议是由IETF(Internet Engineering Task Force)IGP工作小组提出的，是一种基于SPF算法的路由协议。     

Mapping of Sahelian vegetation parameters from ERS scatterometer data with an evolution strategies algorithm

The West African Sahel rainfall regime is known for its spatio-temporal variability at different scales which has a strong impact on vegetation development. This study presents results of the combined use of a simple water balance model, a radiative transfer model and ERS scatterometer data to produce map of vegetation biomass and thus vegetation cover at a spatial resolution of 25 km. The backscattering coefficient measured by spaceborne wind scatterometers over Sahel shows a marked seasonality linked to the drastic changes of both soil and vegetation dielectric properties associated to the alternating dry and wet seasons. For lack of a direct observation, METEOSAT rainfall estimates are used to calculate temporal series of soil moisture with the help of a water balance model. This a priori information is used as input of the radiative transfer model that simulates the interaction between the radar wave and the surface components (soil and vegetation). Then, an inversion algorithm is applied to retrieve vegetation aerial mass from the ERS scatterometer data. Because of the nonlinear feature of the inverse problem to be solved, the inversion is performed using a global stochastic nonlinear inversion method. A good agreement is obtained between the inverse solutions and independent field measurements with mean and standard deviation of −54 and 130 kg of dry matter by hectare (kg DM/ha), respectively. The algorithm is then applied to a 350,000 km² area including the Malian Gourma and Seno region and a Sahelian part of Burkina Faso during two contrasted seasons (1999 and 2000). At the considered resolution, the obtained herbaceous mass maps show a global qualitative consistency (r²=0.71) with NDVI images acquired by the VEGETATION instrument.     

Knight：一个通用知识挖掘工具

现有知识挖掘系统普遍存在通用性不好，发现方法单一的弱点。     

Retrieval Of Morphological Variants In Searches Of Latin Text Databases

This paper reports a detailed evaluation of the effectiveness of a system that has been developed for the identification and retrieval of morphological variants in searches of Latin text databases. A user of the retrieval system enters the principal parts of the search term (two parts for a noun or adjective, three parts for a deponent verb, and four parts for other verbs), this enabling the identification of the type of word that is to be processed and of the rules that are to be followed in determining the morphological variants that should be retrieved. Two different search algorithms are described. The algorithms are applied to the Latin portion of the Hartlib Papers Collection and to a range of classical, vulgar and medieval Latin texts drawn from the Patrologia Latina and from the PHI Disk 5.3 datasets. The effectiveness of these searches demonstrates the effectiveness of our procedures in providing access to the full range of classical and post-classical Latin text databases. This revised version was published online in July 2006 with corrections to the Cover Date.     

基于神经元网络的燃油锅炉烟气氧含量的软

针对目前各种氧含量检测仪表在运行过程中的可靠性差、使用寿命短及价格昂贵等诸多不足，通过探寻锅炉运行中的其他参数与烟气氧含量的映射关系，建立ＢＰ神经元网络，提出了燃油锅炉烟气氧含量的软测量方法。结果表明，其精度完全达到了设计要求。     

遗传算法在混合H_2/H_∞优化控制设计中的应用

介绍了现已成为关键智能计算之一的一种新的全局优化搜索算法—遗传算法，并探讨了在混合Ｈ２／Ｈ∞最优指标下优化控制设计中的应用。其最大特点是：本质并行、全局优化，它不要求目标函数连续和可微，比梯度法和随机搜索算法更适合于ＰＩＤ混合Ｈ２／Ｈ∞优化问题。