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291.
带光学窗口的ICF低温冷冻靶用低温恒温器 总被引:1,自引:0,他引:1
研制了一种热梯度法制备核聚变低温冷冻靶用低温恒温器,通过上下热连接杆使试样盒冷却,配合电加热器以及控温系统,使样品盒的平均温度可以控制在10-40K试验温度范围内,并实现均匀温度梯度。 相似文献
292.
This paper presents an efficient robot calibration method with non-contact vision metrology. Using the coplanar pattern to calibrate camera made the active-vision-based end-effector pose measurement be a feasible and cost-effective way. Kinematic parameter errors were linearized and identified through two-step procedure, thus the singular and non-linear condition was overcome. These errors were then compensated using inverse model method. The whole calibration process is flexible, easy to implement and prevents the error propagation from the earlier stages to the later ones. Calibration was performed on MOTOMAN SV3 industrial robot. Experiment results show that the proposed method is easy to setup and with satisfactory accuracy. 相似文献
293.
The totally coded method (TCM) reveals the same objective law, which governs the gain calculating for signal flow graph as Mason formula does. This algorithm is carried out merely in the domain of code operation. Based on pure code algorithm, it is more efficient because figure searching is no longer necessary. The code-series (CS), which are organized from node association table, have the holoinformation nature, so that both the content and the sign of each gain-term can be determined via the coded method. The principle of this method is obvious and it is suited for computer programming. The capability of the computeraided analysis for Switched Capacitor (SCN) can be enhanced. 相似文献
294.
Meshing Theoretical Study and Simulation on Cylindrical Tri-sine Oscillating Tooth Gear Drive 总被引:2,自引:0,他引:2
The structure of cylindrical tri-sine oscillating tooth gear drive is presented. Based on the space meshing theory, equations of meshing and tooth profile are established and its meshing theory is studied. Using Pro/E, this system is modeled and simulated,which is compared with the above-established equations. 相似文献
295.
A combined first and second-order model, which includes bulk decay and wall decay, was developed to describe chlorine decay in water distribution systems. In the model the bulk decay has complex relationships with total organic carbon (TOC), the initial chlorine concentration and the temperature. Except for the initial stages they can be simplified into a linear increase with TOC, a linear decrease with initial chlorine concentration and an exponential relationship with the temperature. The model also explains why chlorine decays rapidly in the initial stages. The parameters of model are determined by deriving the best fitness with experimental data. And the accuracy of model has been verified by using the experimental data and the monitoring data in a distribution system. 相似文献
296.
IntroductionTheappraisementofenterprisehumanresourcehaspositiveinfluenceonenterpriseandstaff.Throughtheappraisement,anenterprisecanmakegooduseofitsstaff.Meanwhile,thestaffcanfindthepositionfitforhim.Nevertheless,thereisagreatamountoflinguisticinformationintheappraisementofenterprisehumanresource,whichbringsmanydifficultiesforappraisement.Ifthelinguisticvalueinthecourseofappraisementisnotprocessedproperly,thereasonabilityandusefulnessofappraisementresultwillbelargelyreduced.Whatevernumericalap… 相似文献
297.
IntroductionThehandleoffabricshasbeenthesubjectofaverylargenumberofstudiesformorethan30years.FromthepioneeringworkofPierceinthe1930stomorerecenttechniques[1],manystudieshavesoughttorelatehandletospecificfabricmechanicalpropertiesandthroughthemtofiberproperties.Althoughsmoothness,softness,andstiffnessdeterminethephysicalandmechanicalbehaviorofafabricandthesubjectiveassessmentofqualitywhenitishandled,thesensationsperceivedfromthecontactofclothingwiththeskincangreatlyinfluenceouroverallstateofcom… 相似文献
298.
Localization of a Robotic Capsule for GI Motility Inspection with a Portable Ultrasonic System 总被引:5,自引:0,他引:5
IntroductionResearchesonmicromedicaldeviceandmicromedicalrobot,especiallytheinvivoinspectionsystemworkinginalimentarycanalorinbloodvesselwithlittledamageornondamagetohumanbodyhavebeenundertakenandreportedbyexpertsinmanycountries.Thesesystemsusuallyownmanyadvantagessuchas:smallvolume,lowpowerconsumption,littleinterferencetoworkingsurroundings,socangreatlyenlargethescopesofmedicalexaminationandrelievethepatientsofdiscomfortcausedbynormalprocedures.Thecapsuleendoscope“NORIKAsystem”developedby… 相似文献
299.
IntroductionComparedtotraditionalindustry ,microelectronicfab ricationhasthreecharacteristics :highcomplexity ,highprecisionandhighautomatization .Tomeettheprecision ,speedandreliabilityrequirements,machinevisiontech niques,suchasvisionaidedinspectionandregistration ,havebeenintroducedineveryworkingprocedureofinte grated circuitfabricationandsurfacemounttechnology(SMT) .Inspectionandregistrationprecisionmustbecon stantlyincreasedasthesizeofthecomponentbecomessmallerandsmaller .Therefore ,the… 相似文献
300.
教育技术的现代化将在21世纪的教育中起到重要作用,教师的现代化是教育技术现代化的根本,是重中之重。本文从教师思想、角色、基本功和技能技巧、教学方法等方面论述了教育技术现代化对教师的影响。 相似文献