共查询到20条相似文献,搜索用时 11 毫秒
1.
《武汉理工大学学报》2006,(Z3)
With Visual C 6.0 as the language,following the traditional waterfall model and the software engineering theory,utilizing the technique of the dialog box,picture synthesis in VC,the writers present the developing of the woven fabric CAD system under the environment of Windows98.The system includes weave designing,yarn simulating,color matching,han- dling hand sample fabric and the testing effect. The basic methods and effect evaluation have been discussed and developed for the weave designing,yarn appearance simulat- ing and fabric color matching,as well as handling hand sample states the image processing,such as DIB(Device-independent bitmap);meanwhile,the developed system has been tested and run in actual design and textile mill trials.The operated results show that the system runs steadily,efficiently and smart,it can be widely used in yarn and fabric design by using with the merits of convenience,celerity and nicety in shortening the developing periods of product;additionally,it provides in fact a new ap- proach to technical design for textile mills. 相似文献
2.
Based on the loading conditions of engine, applying difference method to solve the hydrodynamic lubrication equation of piston skirt movement, the force acting on piston skirt and the moment on wrist pin were obtained. A computer program for simulating the piston second order motion was conducted to calculate the lateral motion of the upper part and the bottom part of piston skirts of the engine of automotive model CA1091. From the simulated result, the maximal impacting phase and the maximal impacting region of the piston were obtained. The result can be used for designing engine, diagnosing the noise of piston knocking cylinder wall and explaining many practical fault phenomena in theory. 相似文献
3.
Modification of Bitumen with Desulfurized Crumb Rubber in the Present of Reactive Additives 总被引:1,自引:0,他引:1
YEZhigang ZHANGYuzhen KONGXianming 《武汉理工大学学报(材料科学英文版)》2005,20(1):95-97
Bitumen was modified with desulfurized crumb rubber (DCR) in the present of reactive additives . The effect of the kinds and content of the reactive additive on properties of DCR modified bitumen (DCRMB)was investigated. The morphology of DCRMB was characterized by SEM and the changes of the chemical structure of DCRMB without and with the addition of the reactive additive were analyzed by FTIR. The experimented results show that the softening point, the elasticity recoveray and the storage stability of DCRMB were improved significantly by the addition of the reactive additive. This is because that a network structure of rubber in DCRMB was formed and the chemical reaction between C = C double bonds in bitumen and DCR has happened after the reactive additive was added into DCRMB. 相似文献
4.
The determination of the link with the smallest end-to-end network latency in ethernet architecture 总被引:1,自引:0,他引:1
Ethernet fundamental and its data transmission model are introduced in brief and end-to-end network latency was analyzed in this paper. On the premise of not considering transmission quality and transmission cost, latency was the function of the rest of network resource parameter (NRP). The relation between the number of nodes and that of end-to-end links was presented. In ethernet architecture, the algorithm to determine the link with the smallest latency is a polynomial issue when the number of network nodes is limited, so it can be solved by way of polynomial equations. Latency measuring is the key issue to determine the link with the smallest network latency. 3-node brigade (regiment) level network centric warfare (NCW) demonstration platform was studied and the latency between the detectors and weapon control stations was taken as an example. The algorithm of end-to-end network latency and link information in NCW was presented. The algorithm program based on Server/Client architecture was developed. The data transmission optimal link is one whose end-to-end latency is the smallest. This paper solves the key issue to determine the link whose end-to-end latency is the smallest in ethernet architecture. The study can be widely applied to determine the optimal link which is in the complex network environment of multiple service provision points. 相似文献
5.
FAN Ping LIU Qingquan LI Jiachun & SUN Jianping Division of Engineering Science Institute of Mechanics Chinese Academy of Sciences Beijing China 《中国科学E辑(英文版)》2005,48(Z1)
1 Introduction It has been widely accepted that the rainfall infiltration through fractures is one of the most probable factors for slope failure. Recent studies have focused on the relationships between rainfall and slope failure, but the mechanisms of rainfall-induced slope failures have not been fully understood. As a result, many experiments and theoretical studies have been carried out to simulate the infiltration in the fractured soil[1—3]. Aimed at the infiltration in unsaturated rock … 相似文献
6.
EfectsofBreak┐throughStateandSystemRigidityonVibrationandNoiseinBlankingGUOBin(郭斌)LIChunfeng(李春锋)LIUGang(刘钢)GUOTao(郭涛)(Dept.o... 相似文献
7.
桥梁等效静力风荷载广义荷载-响应相关法
董锐1,2,葛耀君2,赵林2,韦建刚1,3
(1.福州大学 土木工程学院,福州350108;
2.同济大学 土木工程防灾国家重点实验室,上海 200092;
3.福建工程学院 土木工程学院, 福州 350118)
摘 要:
根据荷载和响应之间的关系,结构的等效静力风荷载可采用荷载-响应相关法,即LRC(Load-response correlation)法计算。LRC法是计算结构背景响应等效静力风荷载的精确方法。LRC法经典表达式根据结构某一关键位置处的某一关心响应推导得到,并且具有唯一性。本文根据结构全部位置处的某一关心响应推导得到LRC法广义表达式,并将结构的等效静力风荷载以矩阵的形式表达为荷载-响应相关系数、响应-响应相关系数、脉动风荷载RMS值和峰值因子的乘积。与LRC法广义表达式相比较,经典表达式是广义表达式的一种特例。LRC法广义表达式引入了响应-响应相关系数,为结构工程师计算等效静力风荷载提供了更多的选择,同时对LRC法的本质有了更深入的认识。最后,分别以斜拉桥、三跨连续梁桥和悬索桥为例验证了LRC法广义表达式的正确性。
关键词:桥梁;等效静力风荷载;荷载-响应相关法;背景响应;广义表达式;荷载-响应相关系数;响应-响应相关系数
相似文献8.
Nation modified Pt nano-particles with size about 4nm were synthesized. The modified particles were absorbed on the surface of carbon nanotubes and used as electro-catalysts for proton exchange membrane fuel cell. Due to the plentiful proton channels provided by the modifying Nation ionomers, the single fuel cell with the modified Pt catalyst has a promised performance . The output was 0.282 W/cm^2 with Pt loading of 0.1 mg/cm^2 ,better than that of unmodified one, which was 0.273 W/cm^2 with Pt loading of 0.1mg/cm^2 . 相似文献
9.
郁鸽 《中国科学E辑(英文版)》1996,(5)
The fundamentals of a new method of theoretically studying the kinetics of the phase transformation with nudeation and growth mechanism are demonstrated.Startingfromfinite,heterogeneous system,the survival probability of the individual sites for the given annealing time can be calculated by the present treatment,so that the kinetics equation under general conditions can be derived.In comparison to the classical treatment,the new derivations are not only rigorous and transparent,but also can be used to deal with the non-homogeneous systems and the non-steady process.Also the problems concerning the interference of more than one simultaneously occurring transformations and the correlation between different sites can be studied. 相似文献
10.
Determination of the solvation film thickness of dispersed particles with the method of Einstein viscosity equation 总被引:1,自引:0,他引:1
Changsheng Peng Shaoxian Son Shouci Lu 《北京科技大学学报(英文版)》2005,12(4):370-375
The dispersion of a solid particle in a liquid may lead to the formation of solvation film on the particle surface, which can strongly increase the repulsive force between particles and thus strongly affect the stability of dispersions. The solvation film thickness, which varies with the variation of the property of suspension particles and solutions, is one of the most important parameters of the solvation film, and is also one of the most difficult parameters that can be measured accurately. In this paper, a method, based on the Einstein viscosity equation of dispersions, for determining the solvation film thickness of particles is developed. This method was tested on two kinds of silica spherical powders (namely M1 and M2) dispersed in ethyl alcohol, in water, and in a water-ethyl alcohol mixture (1:1 by volume) through measuring the relative viscosity of dispersions of the particles as a function of the volume fraction of the dry particles in the dispersion, and of the specific surface area and the density of the particles. The calculated solvation film thicknesses on M1 are 7.48, 18.65 and 23.74 nm in alcohol, water and the water-ethyl alcohol mixture, 12.41, 12.71 and 13.13 nm on M2 in alcohol, water and the water-ethyl alcohol mixture, respectively. 相似文献
11.
Dequan Peng Xinde Bai and Baoshan Chen Department of Materials Science Engineering Tsinghua University Beijing China Jianzhong Chemical Corperation Yibin China 《北京科技大学学报(英文版)》2006,13(2):158-163
1. IntroductionZIRLO alloy is widely used in the nuclear industrybecause of its low thermal neutron capture cross sec-tion, favorable mechanical properties, and good corro-sion resistance. For example, ZIRLO alloy can serve asfuel cladding, spreaders for … 相似文献
12.
YIN Meizhen HAN Yingchao DAI Honglian LI Shipu 《武汉理工大学学报(材料科学英文版)》2006,21(4):102-104
The inhibition effect of hydroxyapatite ( HAP ) nanoparticles on hepatocarcinoma was investigated in vivo. The human hepatocarcinoma cell line Bel- 7402 was transplanted subcutaneously into nude mice. Hydroxyapatite nanoparticles suspension at a dose of 0. 2 mL was injected into the transplanted tumors every day for 2 weeks, and saline was used us control. The efficacy of hydroxyapatite nanoparticles on this carcinoma was surveyed and morphological changes of tissue and cells were observed by light microscopy and transmission electron microscopy (TEM). Experimental results show that hydroxyapatite nanoparticles have a visible destructive effect on the structures of hepatocarcinoma cells and tissue. The inhibition rates of tumor growth were 77.21% and 51. 32% after intra-tumor injection of hydroxyapatite nanoparticles for 1 week and 2 weeks, respectively. Compared with the control group, hydroxyapatite nanoparticles can also prolong the survival time of the nude mice bearing this cancer significantly. This indicates that hydroxyapatite nanoparticles have the therapeutic potential on hepatoma in vivo. 相似文献
13.
Synthesis and Properties of Water-soluble CdSe/ZnS Nanocrystals with the Type-Ⅰ Core/Shell Structure
The synthesis of CdSe/ZnS core/shell nanocrystals though aqueous phase using the coprecipitation method was reported. The influences of factors such as injection methods and dosages of precursors, reaction duration of water-bathing and the initial CdSe:ZnS molar ratio were discussed. In comparison to the CdSe plain core nanocrystals, the CdSe/ZnS core/shell nanocrystals show much brighter photoluminescence demonstrated by the photoluminescence spectra. The epitaxial growth of the core/shell structures was verified by TEM and XRD. 相似文献
14.
Validation of the numerical simulation of fluid flow in the continuous casting tundish 总被引:1,自引:0,他引:1
LifengZhang 《北京科技大学学报(英文版)》2005,12(2):116-122
The 3-dimensional fluid flow in a water model of the continuous casting tundish is simulated with the k-ε two-equation turbulence model. The methods to decide the size of wall-adjacent grids and the effects of residuals and mesh size on the simulation accuracy are discussed. The current investigation concludes that the following condition should be satisfied to get accurate enough simulation results: (1) If the dimension of the domain is in the order of cubic meters, the average size of cells in the mesh system should be at least smaller than 30 mm; (2) The normalized non-scaled residual should be reached at least smaller than 10^-4. 相似文献
15.
R/S Analysis and its Application in the Forecast of Mine Inflows 总被引:1,自引:0,他引:1
YANG Yong-guo YUAN Jian-fei CHEN Suo-zhong 《中国矿业大学学报(英文版)》2006,16(4):425-428
1 Introduction As the first and foremost energy source of China, the irreplaceable role of coal will be played in the national economy for quite a long time. The hydro- geological conditions of coal mines in China are complicated: Karst water is dominant in coal mines of the Carboniferous and Permian periods in North China and of late the Permian period in South China, while alluvial water dominates the mines of the Qua- ternary period in the Huanghuai Plain. Many mining areas in China, … 相似文献
16.
YAN Zhi-gang ZHANG Hai-rong DU Pei-jun 《中国矿业大学学报(英文版)》2006,16(4):433-438
To recognize the presence of the headstream of gushing water in coal mines, the SVM (Support Vector Machine) was proposed to analyze the gushing water based on hydrogeochemical methods. First, the SVM model for headstream analysis was trained on the water sample of available headstreams, and then we used this to predict the unknown samples, which were validated in practice by comparing the predicted results with the actual results. The experimental results show that the SVM is a feasible method to differentiate between two headstreams and the H-SVMs (Hierachical SVMs) is a preferable way to deal with the problem of multi-headstreams. Compared with other methods, the SVM is based on a strict mathematical theory with a simple structure and good generalization properties. As well, the support vector W in the decision function can describe the weights of the recognition factors of water samples, which is very important for the analysis of headstreams of gushing water in coal mines. 相似文献
17.
《中国科学E辑(英文版)》2005,(Z2)
With the requirement of quantitative application of remote sensing, it is more pressing to improve the accuracy of remote sensing. Slater proposed a calibration method using a large homogeneous surface target [1], which has been proved promising and has been applied to many sensors[2―10], such as TM, ETM+, HRVIR. However, this method re-quired so much labor and fund that it could not produce enough calibration coefficients. In addition, it could not be applied to history data. Later, many… 相似文献
18.
AStudyontheMovingAccuracyoftheSlideinthePress¥(陈维民)(曹喜滨)(刘刚)(高乃光)CHENWeimin;CAOXibin;LIUGang;GAONaiguang(Dept.ofMaterialScien... 相似文献
19.
In an anode baking horizontal flue ring furnace, the temperature distribution is one of the key factors influencing the quality of baked anode and is closely correlated with the gas flow. To understand the gas flow distribution in the flue, Navier-Stokes equation with “k-ε“ two-equation turbulence model was adopted and the simulation on the gas flow was performed. The numerical simulation results showed that the even direction of gas flow should be considered in the design of flue baffles and the gas flow distribution was really uneven in the flue in practical use. By adjusting the number and location of flue baffles rationally, the even distribution of gas flow can be improved obviously. 相似文献
20.
This paper presents an analysis of the changes of the longitudinal and lateral profiles in the meander- ing reach of the Lower Wei River over the period from October 1973 to October 1976 during the course of degradation.Analysis results indicated that retrogressive erosion and subsequent downstream erosion occurred in the reach due to the lowering in the Tongguan elevation and the inflowing water carrying low sediment con- centrations.At the end of the degradation,the main channel widths of the majority of sections were increased by 70 to 110 percent,and the elevation differences between the main channel and the floodplain were de- creased slightly by 2 to 45 percent,which caused a decrease in the water stage under the same discharge,the formation of a channd with relatively wide and shallow cross-sectional profiles,and an increase of 50 to 150 percent in the geomorphological coefficients.Therefore,the degradation in this reach was mainly characterized by channel widening,not by channel undercutting. 相似文献