TopSolid CAD/CAM系统--高端的功能,中端的价格

一、前言 法国Missler公司是一家专业的CAD/CAM软件开发商,总部位于法国巴黎,拥有众多的欧洲、美洲用户,法国汽车制造商雷诺(Renault)就是其典型用户之一.在亚洲,越来越多的企业选择了Missler公司的产品作为其工具,日立(Hitachi)公司则是典型代表.     

智通电子笔迹技术推动电子政务快速发展

随着无纸化办公和电子商务的普及和发展,我们正处于一个移动电子商务的时代。智通公司的产品Sign-it~(TM)代表了新一代的生物鉴别方法,用户可以电子地签署电子文档以使得整个批准和授权过程变得更自然、更直观,此种技术可防止无意或恶意地篡改文档,并且它是可靠的、有效和可行的批准和处理电子文档的方法。Sign-it~(TM)的应用领域包括:工程文件/图档的管理、销售过程的自动化、医疗文件的追踪、财务文     

ENGINE解决方案与3G

爱立信的ENGINE解决方案采用了3GPP定义的网络架构,与爱立信3G网络解决方案使用统一的业务网络和相同的核心网络,为将来3G的引入、固定网和移动网的融合打下了坚实的基础。1.相同的网络架构ENGINE和3GPP均采用分层的网络结构,即业务层、控制层、承载层和接入层等层面。控制层面中的服务器,通过控制承载层中的边缘节点(Edge)中的媒体网关,为相应的接入网络的用户提供业务支持。根据所支持的终端和业务的不同,分为三种支持系统:固定电话业务域的电话业务软交换系统(TeS)、多媒体业务域的多媒体业务软交换系统BBCS/IMS,以及移动电…     

2G通向3G的成功运营模式

随着3G在全球的发展,GSM网络运营商所面临的任务是快速、经济地建立3G网络,提供多样化的数据服务。但如何平稳地从2G过渡到3G模式,采用何种策略快速、经济地部署和运营3G系统,是当前GSM网络运营商面临的挑战。一、GSM与WCDMA过渡阶段由于市场竞争的压力,许多GSM运营商将会积极地部署WCDMA,推出多媒体移动互联网服务,在未来几年里提供数据服务。GSM运营商将主要经历三个阶段:譹以语音为中心的纯GSM业务;譺全国范围内的GPRS无线数据服务,并在某些地区开展高速WCDMA业务;譻高速多媒体移动互联网WCDMA与GSM业务。各阶段不同…     

Effects of sulfurous acid on anodic process of gold electrode in thiourea solution

Thioureaitselfisunstableunderanappropriateoxidizingconditionandcanbeoxidized .Theoxida tion productsofthioureadependontheoxidants ,suchashydrogenperoxide ,ferriciron .Itwasreport edthatwithferricironetc ,thioureadecomposedasfollows[7] .2SC(NH2 ) 2 (SC(NH)NH2 ) 2 + 2H++ 2e(2 )ThepotentiodynamicpolarizationcurvesshowninFig .1wereobtainedin 0 .0 5mol/Lthiourea(TU )solutionforafreshlygroundstationarygoldelectrodestartsfrom 0to 1.2 0VvsSCE .FromFig .1itcanbeseenthatthefirstanodicshoulderais…     

A numerical method based on probability theory

1　INTRODUCTIONAprobabilisticcomputingmethodfora 3 dimension alDirichlet problemwasproposedin Ref.[1].ItisknownthatneitherfiniteelementmethodnordifferencemethodcansolvetheDirichletproblemsoverdomainswithcomplexboundaries.Howeveraccordingtothechar acteristicsofBrownianfamilywithdriftandsomeotherprobabilistictheoryamethodwhichcansolvethemeasilyisobtained .Hencethismethodcanbeappliedtomanyphysicalproblems.Moreover,whenweonlywanttokownthevalueofthesolutiononseveralpointsinthedo main ,themet…     

Optimization principle of combined surface and underground mining and its applications

The pit limit optimization is discussed, which is one of the most important problems in the combined mining method, on the basis of the economic model of ore-blocks. A new principle of the limit optimization is put forward through analyzing the limitations of moving cone method under such conditions. With a view to recovering as much mineral resource as possible and making the maximum profit from the whole deposit, the new principle is to maximize the sum of gain from both open-pit and underground mining. The mathematical models along the horizontal and vertical directions and modules for software package (DM&MCAD) have been developed and tested in Tonglushan Copper Mine. It has been proved to be rather effective in the mining practice.     

Prediction control of active power filters

A prediction method to obtain harmonic reference for active power filter is presented. It is a new use of the adaptive predictive filter based on FIR. The delay inherent in digital controller is successfully compensated by u-sing the proposed method, and the computing load is not very large compared with the conventional method. Moreover, no additional hardware is needed. Its DSP-based realization is also presented, which is characterized by time-variant rate sampling, quasi synchronous sampling, and synchronous operation among the line frequency, PWM generating and sampling in A/D unit. Synchronous operation releases the limitation on PWM modulation ratio and guarantees that the electrical noises resulting from the switching operation of IGBTs do not interfere with the sampled current. The simulation and experimental results verify the satisfactory performance of the proposed method.     

Optimization of efficient stable reagent of alkaline thiourea solution for gold leaching

1　INTRODUCTIONThiourea ,asanontoxic goldleachingreagentsubstitutingcyanide ,hasattractedtheinterestofmanyresearchersallovertheworldsincethedissolu tionofgoldinthioureasolutionwasfirstreportedin194 1,andaseriesofstudiesonthetheoryandtech nologyforleachinggoldbythioureahavebeencon ducted[1 3] .Mostreportson golddissolutioninthioureasolutionwereconcernedwithacidicmedia .Itwasdifficultforgoldtodissolveinalkalinesolutionbecauseofthepassivationofelementsulfurproducedbytheirreversibledecompositi…     

Effects of symmetrically alternative rotating flow on flocculation

1　INTRODUCTIONTheflocculationisusuallydefinedasaprocessinwhichthedestabilizedsolidparticlesareaggregatedbythebridgingofpolymericflocculants .Theformationofflocsisdeterminedbytwosteps.Oneistheap proachingandcollision ,theotheristheflocgrowing .Thecollisionisachievedbythreemechanismsinclud ingtheBrownianmotionof particles ,namedasperikineticflocculation ;thedifferencesinsettlingve locityofparticleswithvarioussizes ,socalleddiffer entialsettlingandtheimposedfluidvelocitygradientsfrommixing …