Aeronumeric optimal design of a wing-in-ground-effect craft

An optimization technique was used to generate a wing-in-ground-effect (WIG) configuration which can achieve the maximum lift and satisfy the height stability criteria within the design constraints. For the analysis of the aerodynamic coefficients, the vortex lattice method (VLM) was applied with the inviscid and potential flow approximations. The sequential quadratic programming (SQP) method, which is a nonlinear optimization method, was employed as an optimization tool. The lift and moment coefficients, including the stability analysis computed by VLM, were compared with the experimental results of a medium-sized WIG, and a good correlation was found between them. In addition, the optimization tool was validated by finding the optimal position of the side wing attached on the WIG craft. Then, various optimum examples are shown, with generation of the wing section, the determination of the planform configuration, the aspect ratio, and the position of the tail wing within the design constraints. It was shown that the present optimization tool can be used effectively for the optimal design of a WIG craft.     

模糊商空间理论两个定理的补充

张铃等在“模糊粒度计算方法”中,核心定理证明中构造的等价关系是循环定义的,且没有证明它的截关系与商空间所对应的等价关系是相等的;模糊等价关系的粗细定义与模糊集理论的意义不一致,容易引起歧义．本文用通用的模糊数学符号和序代数理论的方法和观点对其进行修正和补充,给出两个定理的完整证明,使得相关结果的表达更简洁和规范,完善了模糊商空间理论．     

预应力锚杆格子梁加固技术在边坡工程中的应用研究

预应力锚杆格子梁以其造价低廉、治理效果良好在边坡工程中得以大量应用。结合某高速公路k253＋700-k254＋220边坡工程,将预应力锚杆格子梁加固技术应用于该工程,然后选取该边坡农机天桥下方k253＋900边坡,建立有限元模型并分析了预应力锚杆格子梁加固方案的加固效果。分析结果表明,采用一级边坡锚杆预应力格子梁加固方案的加固效果非常职显。最后结合现场监测的数据分析,验证了该加固方案的有效性。     

天津海河隧道抗震研究概述

天津地处华北地震区的华北平原地震带上,中央大道海河隧道是抗震重点工程。该文介绍了海河隧道的工程地质概况,在此基础上,上海交通大学提出了用大型有限元三维仿真模拟和经典的等效质点-弹簧模型两种方法进行抗震分析,并首次提出了"SSUM(Sophisticated and Simple Unified Method)"抗震分析方法,对今后类似工程有重要的借鉴作用。     

铁路货运数据仓库多维视图的组织及其物化策略

合理地组织数据仓库的多维视图，并将部分视图物化，是提高数据仓库查询性能的一个有效途径，本文结合铁路货运数据仓库模型的研究，探讨了数据仓库数据立方体多维视图的依赖格组织法及其物化策略，介绍了物化视图选择的贪心法和空间边界法，并结合空间边界法提出了一种新的价值模型。     

雷达辐射源的两种识别算法比较

针对雷达辐射源识别中采用的马氏距离法和改进的格贴近度法两种相似性测量方法进行研究,分析了两种算法的相同和相异点及优劣性.指出了两种算法在雷达辐射源识别中的特点和存在的问题.     

浅析高边坡防护设计实例

锚拉格构梁是近年高边坡防护应用的较多形式之一。该文结合工程实例,浅谈高达40m以上的五级边坡支护的设计与计算。     

A Characterization of Weak Sequential Continuity of Lattice Operations on Banach Lattices

This paper deals with a characterization for a Banach lattice in which the lattice operations are weakly sequentially continuous. As an application an elementary proof for an important result due to Wickstead is provided.     

PERSISTENT CURRENT IN A ONE-DIMENSIONAL MESOSCOPIC RING WITH ELECTRON-PHONON INTERACTION IN THE LATTICE MODEL

IntroductionSince the pioneering work of Büttiker etal[1,2 ] ,the problem of persistentcurrent in a meso-scopic ring has attracted much recent atten-tion[3～ 6] . In a normal- metal ring threaded by amagnetic flux,a persistent current exists as longas the phase coherence of electron is pre-served[1,2 ,4 ] . With the gauge transformation,thevector potential can be removed from Schrodingerequation with a modified boundary conditionψn(x L ) =exp(2πi/0 )ψn(x) ,where0 =h/e is theflux q…     

Ideal resolution principle for lattice-valued first-order logic based on lattice implication algebra

As a continuate work,ideal-based resolution principle for lattice-valued first-order logic system LF(X) is proposed,which is an extension of α-resolution principle in lattice-valued logic system based on lattice implication algebra.In this principle,the resolution level is an ideal of lattice implication algebra,instead of an element in truth-value field.Moreover,the soundness theorem is given.In the light of lifting lemma,the completeness theorem is established.This can provide a new tool for automated reasoning.