模糊综合评价技术在住宅综合性能评估中的应用研究

依据《商品住宅性能评定方法和指标体系》正确地对商品住宅地性能进行评价 ,是评定商品住宅质量等级的重要依据。本文主要论述如何运用数学方法分析和处理住宅综合质量评定中大量存在的模糊问题以及如何建立相应的等级评价准则和进行等级评判     

线性规划模型的自动生成与求解

本文描述了《有色企业经济活动分析决策支持系统》模型库中线性规划模型的自动生成与求解系统的设计思想、方法及实现     

Asymptotic deformation and stress fields at the tip of a sharp notch in an elastic-plastic material

The singular elastic-plastic stress, strain and the displacement fields at the tip of a sharp notch for both plane stress and plane strain conditions are investigated analytically. The material is assumed to be governed by the deformation theory of plasticity with linear strain hardening characteristic. Since the elastic strain is retained in the analysis, the final strain and displacement fields can be separated into the elastic and the plastic parts. In the case with zero notch angle, the results reduce to the classical crack problem. The relationship of the amplitude of the near crack tip elastic-plastic field to the elastic far field is obtained. Both mode I and mode II cases are investigated. The mixed mode case is also discussed.     

有机电沉积涂料的新动向

阴极电沉积涂料是 2 0世纪 70年代以来发展起来的一种新的涂装方法 ,具有挥发性有机物 (VOCs)和有害空气污染物(HAPs)含量低、防蚀能力强、漆膜质量好、涂料利用率高、适合涂装结构复杂的构件和设备等特点。介绍了近年来阴极电沉积涂料研发的新动向。它们主要集中在有机双层电涂和高分子 聚电解质 /低聚物电解质复合物多层电涂体系 ,这些新的电涂体系在涂料的稳定性以及涂层的物理化学性质和力学性能方面具有明显的改进。     

瑞典Laholm沼气厂的运行实践

瑞典沼气的总产量约为1400GW·h,约有60%产自200多家市政污水处理厂的污泥消化池,垃圾填埋场的产量占30%,剩余的10%主要来源于工业废水处理厂和混合消化厂。一般情况下,沼气用作热源和发电,也可以作为汽车燃料。有机废物转化成沼气的同时还产生了消化残余物,可用作生物肥料。在瑞典有机废物填埋要课以重税,并且自2005年开始该国已严禁有机物的填埋处理,所以人们逐渐开始了对有机物混合消化的重视和研究。目前瑞典约有10家沼气厂利用厌氧消化处理收集来的各种有机废料,总处理能力>20×104t/a。多数沼气厂将牲畜粪便作为主要原料,再辅以其他…     

套管液压式φ106mm密封加固系统研究

针对套管液压式φ100mm密封加固系统在实际应用中的缺点,开展了大通径密封加固技术专题研究.研制的套管液压式φ106mm密封加固器承压达30 MPa以上,悬挂力达到500kN以上,可下入φ100mm小直径分层管柱.现场应用见到了明显的效果,为提高小直径分采分注管柱寿命创造了条件.     

Diffusion Behaviour of Fe-Cu Interface of Copper Brazed Double-wall Steel Tubes

By means of electron probe(EPMA),scanning electron microscope(SEM),and optical microscope(QM),the diffusion behaviour on the Fe-Cu interface of copper brazed double-wall steel tubes andthe microstructure of the diffusion layer have been investigated.There are three kinds of metallurgicalbonds between copper plating layer and steel substrate: (1)the Cu diffusing into steel substratealong grain boundary of ferrite;(2)the Cu diffusion into grain bulk of ferrite: (3)the Fe diffusing intoCu layer.The copper brazed double-wall steel tubes are formed by the combination of the diffusionsmentioned above and this is the reason for excellent mechanical and technological properties of thecopper brazed double-wall steel tubes.     

A COMPUTER-AIDED UNIFIED APPROACH TO MODELING PWM AND RESONANT CONVERTERS

This letter puts forward a method of modeling for the steady-state and small signal dynamic analysis on PWM, quasi-resonant and series/（parallel） resonant switching converters based on pulse-waveform integral approach. As an example, PWM and quasi-resonant converters are used to discuss the principle of the approach. The results are compared with those in the relative literatures. Computer aided analysis are made to confirm the correctness.     

An efficient approach for calculating the dispersions of photonic-crystal fibers: design of the nearly zero ultra-flattened dispersion

A novel and efficient approach is proposed to calculate the dispersions of the guided modes of the photonic-crystal fibers (PCFs). Based on the vector boundary-element method (VBEM), the surface integral equations for the first and second derivatives of the propagation constants with respect to the wavelength are explicitly derived. Compared with the three-point finite-difference approach, which needs to solve and search three effective indexes near the interested wavelength, this approach can determine the dispersions of the PCFs by only solving one effective index at this wavelength based on the derived formulations. This novel approach saves over 60% computing time without losing the accuracy. Based on this approach, a novel four-ring PCF is designed by optimizing only three geometrical parameters to achieve the nearly zero ultra-flattened dispersion property. Compared with previously presented dispersion-flattened PCFs, the design procedure for the four-ring structure could be more efficient and easier because relatively lesser parameters need to be optimized.     

60Co辐照预处理对苹果片脱水特性和品质的影响

进行了不同辐照剂量、热风温度、切片厚度对苹果脱水速率及品质的影响试验,结果表明该三因子影响苹果片的脱水速率和外观质量.辐照剂量增加,热风温度增高,脱水速率高,VC含量和复水比下降.辐照剂量、热风温度、切片厚度三因素对脱水速率和干制品的外观质量、VC含量、复水比等四指标大都呈显著影响.