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Visual fatigue relief zone in an extra-long tunnel using virtual reality with wearable EEG-based devices 被引量:6
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作者 LI Xiao-jun LING Jia-xin SHEN Yi 《Journal of Central South University》 SCIE EI CAS CSCD 2021年第12期3871-3881,共11页
Long-time driving and monotonous visual environment increase the safety risk of driving in an extra-long tunnel. Driving fatigue can be effectively relieved by setting the visual fatigue relief zone in the tunnel. How... Long-time driving and monotonous visual environment increase the safety risk of driving in an extra-long tunnel. Driving fatigue can be effectively relieved by setting the visual fatigue relief zone in the tunnel. However, the setting form of visual fatigue relief zone, such as its length and location, is difficult to be designed and quantified. By integrating virtual reality(VR) apparatus with wearable electroencephalogram(EEG)-based devices, a hybrid method was proposed in this study to assist analyzers to formulate the layout of visual fatigue relief zone in the extra-long tunnel.The virtual environment of this study was based on an 11.5 km extra-long tunnel located in Yunnan Province in China.The results indicated that the use of natural landscape decoration inside the tunnel could improve driving fatigue with the growth rate of attention of the driver increased by more than 20%. The accumulation of driving fatigue had a negative effect on the fatigue relief. The results demonstrated that the optimal location of the fatigue relief zone was at the place where driving fatigue had just occurred rather than at the place where a certain amount of driving fatigue had accumulated. 展开更多
关键词 virtual reality visual environment driving fatigue extra-long tunnel EEG-based device
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A Review in the Core Technologies of 5G: Device-to-Device Communication, Multi-Access Edge Computing and Network Function Virtualization 被引量:2
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作者 Ruixuan Tu Ruxun Xiang +1 位作者 Yang Xu Yihan Mei 《International Journal of Communications, Network and System Sciences》 2019年第9期125-150,共26页
5G is a new generation of mobile networking that aims to achieve unparalleled speed and performance. To accomplish this, three technologies, Device-to-Device communication (D2D), multi-access edge computing (MEC) and ... 5G is a new generation of mobile networking that aims to achieve unparalleled speed and performance. To accomplish this, three technologies, Device-to-Device communication (D2D), multi-access edge computing (MEC) and network function virtualization (NFV) with ClickOS, have been a significant part of 5G, and this paper mainly discusses them. D2D enables direct communication between devices without the relay of base station. In 5G, a two-tier cellular network composed of traditional cellular network system and D2D is an efficient method for realizing high-speed communication. MEC unloads work from end devices and clouds platforms to widespread nodes, and connects the nodes together with outside devices and third-party providers, in order to diminish the overloading effect on any device caused by enormous applications and improve users’ quality of experience (QoE). There is also a NFV method in order to fulfill the 5G requirements. In this part, an optimized virtual machine for middle-boxes named ClickOS is introduced, and it is evaluated in several aspects. Some middle boxes are being implemented in the ClickOS and proved to have outstanding performances. 展开更多
关键词 5th Generation Network virtualIZATION device-To-device COMMUNICATION Base STATION Direct COMMUNICATION INTERFERENCE Multi-Access EDGE COMPUTING Mobile EDGE COMPUTING
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INTELLIGENT VIRTUAL CONTROL:MEASURING INSTRUMENT FROM WHOLE TO PART 被引量:19
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作者 Qin Shuren Tang BaopingCollege of Mechanical Engineering, Chongqing University, Chongqing 400044, China 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2002年第2期131-135,共5页
A new concept called intelligent virtual control (IVC), which can be drivenby measuring functions, is put forward. This small 'intelligent measurement instrument unit (IMIU)',carrying with functions of instrum... A new concept called intelligent virtual control (IVC), which can be drivenby measuring functions, is put forward. This small 'intelligent measurement instrument unit (IMIU)',carrying with functions of instrument, consists of different types of intelligent virtualinstrument (IVI) through individual components together as building blocks and can be displayeddirectly on the computer screen. This is a new concept of measuring instrument, and also animportant breakthrough after virtual instrument (VI). Virtual control makes instrument resourcesobtain further exploitation. It brings about a fundamental change to the design and manufacturingmode. The instrument therefore, can not only be produced directly inside a PC, but the product isinvolved in the 'green product' system. So far, all the present digital instruments will grow to bereplaced by intelligent control with green characteristics. 展开更多
关键词 Intelligent virtual control Measurement instrument Whole Part
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DEVELOPMENT OF VIRTUAL INSTRUMENT IN CHARACTERISTIC ANALYSIS OF ROTATING MACHINERY BASED ON INSTANTANEOUS FREQUENCY ESTIMATION 被引量:4
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作者 YangJiongming QinShuren +1 位作者 JiZhong GuoYu 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2004年第4期490-493,共4页
Based on the recently quick-developing time-frequency analysis (TFA)technique and virtual instrument (VI) technique, a virtual instrument in characteristic analysis ofrotating machinery is researched and developed suc... Based on the recently quick-developing time-frequency analysis (TFA)technique and virtual instrument (VI) technique, a virtual instrument in characteristic analysis ofrotating machinery is researched and developed successfully. By utilizing instantaneous frequencyestimation (IFE) theoretics of TFA technique, and based on IFE of peak searching on thetime-frequency spectrum, order analysis (OA) functions is put forward and implemented, such as orderspectrum, order spectrum matrix, order tracking, order tracking filtering, and order componentextraction, etc. Unlike the home and abroad existing popular characteristic analyzers, which needkey phasing devices such as shaft encoder, phase-locked loop (PLL), phase-locked multiple frequency,tachometer, etc, to implement constant angle sampling directly or indirectly, whereas thisinstrument only uses the vibration signal of rotating machinery to carry out OA. This instrumentmakes up the shortage of these traditional instruments in analyzing the non-stationary signal ofrun-up and run-down process of rotating machinery. Therefore, it is a great breakthrough for theexisting order analyzers. 展开更多
关键词 Rotating machinery Time-frequency analysis Instantaneous frequency Orderanalysis virtual instrument
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Design of Onboard Instrument Based on Virtual Instrument Technology 被引量:2
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作者 TANG Baoping ZHONG Yuanchang QIU Jianwei (Department of Mechatronics,College of Mechanical Engineering,Chongqing University,Chongqing 400030,China 《武汉理工大学学报》 CAS CSCD 北大核心 2006年第S2期412-416,共5页
After analyzing and comparing the traditional automobile instrument,the onboard instrument based on virtual instrument technology is designed in this paper.The PC/104 computer was employed as the core processing unit ... After analyzing and comparing the traditional automobile instrument,the onboard instrument based on virtual instrument technology is designed in this paper.The PC/104 computer was employed as the core processing unit of the onbaard in- strument,and the several intelligent data acquisition nodes are set and connected by the CAN bus,through which the nodes can com- municate with the core processing unit.The information of the vehicle’s working condition can be displayed synthetically by adopt- ing virtual instrument technology.When the working condition goes beyond its limit,the system can emit an alarm,record and storage the abnormal condition automatically,and suggest how to deal with the abnormity urgently.The development background and design idea of onboard information system were elaborated in the paper.The software,the hardware architecture and the principle of onboard information system were introduced in detail. 展开更多
关键词 virtual instrument EMBEDDED TECHNOLOGY PC/104 CAN BUS
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V–L decomposition of a novel full-waveform lidar system based on virtual instrument technique 被引量:2
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作者 徐帆 王元庆 《Chinese Physics B》 SCIE EI CAS CSCD 2015年第10期262-273,共12页
A novel three-dimensional(3D) imaging lidar system which is based on a virtual instrument technique is introduced in this paper. The main characteristics of the system include: the capability of modeling a 3D objec... A novel three-dimensional(3D) imaging lidar system which is based on a virtual instrument technique is introduced in this paper. The main characteristics of the system include: the capability of modeling a 3D object in accordance with the actual one by connecting to a geographic information system(GIS), and building the scene for the lidar experiment including the simulation environment. The simulation environment consists of four parts: laser pulse, atmospheric transport,target interaction, and receiving unit. Besides, the system provides an interface for the on-site experiment. In order to process the full waveform, we adopt the combination of pulse accumulation and wavelet denoising for signal enhancement.We also propose an optimized algorithm for data decomposition: the V-L decomposition method, which combines Vondrak smoothing and laser-template based fitting. Compared with conventional Gaussian decomposition, the new method brings an improvement in both precision and resolution of data decomposition. After applying V-L decomposition to the lidar system, we present the 3D reconstructed model to demonstrate the decomposition method. 展开更多
关键词 lidar system virtual instrument Vondrak smoothing laser-template based fitting
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Virtual instrument for monitoring process of brush plating 被引量:1
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作者 JING Xue-dong XU Bin-shi WANG Cheng-tao ZHU Sheng DONG Shi-yun 《中国有色金属学会会刊:英文版》 CSCD 2004年第z1期126-131,共6页
A virtual instrument(Ⅵ) was developed to monitor the technological parameters in the process of brush plating, including coating thickness, brush-plating current, current density, deposition rate, and brush plating v... A virtual instrument(Ⅵ) was developed to monitor the technological parameters in the process of brush plating, including coating thickness, brush-plating current, current density, deposition rate, and brush plating voltage. Meanwhile two approaches were presented to improve the measurement accuracy of coating thickness. One of them aims at eliminating the random interferences by moving average filtering; while the other manages to calculate the quantity of electricity consumed accurately with rectangular integration. With these two approaches, the coating thickness can be measured in real time with higher accuracy than the voltage-frequency conversion method. During the process of plating all the technological parameters are displayed visually on the front panel of the Ⅵ. Once brush current or current density overruns the limited values, or when the coating thickness reaches the objective value, the virtual will alarm. With this Ⅵ, the solution consumption can be decreased and the operating efficiency is improved. 展开更多
关键词 BRUSH PLATING virtual instrument COATING thickness MEASUREMENT NANO-COMPOSITE COATING
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Exciting Forces for a Wave Energy Device Consisting of a Pair of Coaxial Cylinders in Water of Finite Depth 被引量:1
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作者 Mohammad Hassan Swaroop Nandan Bora 《Journal of Marine Science and Application》 2013年第3期315-324,共10页
Two coaxial vertical cylinders-one is a riding hollow cylinder and the other a solid cylinder of greater radius at some distance above an impermeable horizontal bottom,were considered.This problem of diffraction by th... Two coaxial vertical cylinders-one is a riding hollow cylinder and the other a solid cylinder of greater radius at some distance above an impermeable horizontal bottom,were considered.This problem of diffraction by these two cylinders,which were considered as idealization of a buoy and a circular plate,can be considered as a wave energy device.The wave energy that is created and transferred by this device can be appropriately used in many applications in lieu of conventional energy.Method of separation of variables was used to obtain the analytical expressions for the diffracted potentials in four clearly identified regions.By applying the appropriate matching conditions along the three virtual boundaries between the regions,a system of linear equations was obtained,which was solved for the unknown coefficients.The potentials allowed us to obtain the exciting forces acting on both cylinders.Sets of exciting forces were obtained for different radii of the cylinders and for different gaps between the cylinders.It was observed that changes in radius and the gap had significant effect on the forces.It was found that mostly the exciting forces were significant only at lower frequencies.The exciting forces almost vanished at higher frequencies.The problem was also investigated for the base case of no plate arrangement,i.e.,the case having only the floating cylinder tethered to the sea-bed.Comparison of forces for both arrangements was carried out.In order to take care of the radiation of the cylinders due to surge motion,the corresponding added mass and the damping coefficients for both cylinders were also computed.All the results were depicted graphically and compared with available results. 展开更多
关键词 DIFFRACTION finite depth virtual boundary exciting force wave energy device coaxial cylinder
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Feature Extraction and Diagnosis System Using Virtual Instrument Based on CI 被引量:1
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作者 Renping Shao Xinna Huang Yonglong Li 《Journal of Software Engineering and Applications》 2010年第2期177-184,共8页
Through investigating intelligent diagnosis method of Computational Intelligence (CI) and studying its application in fault feature extraction, a gear fault detection and Virtual Instrument Diagnostic System is develo... Through investigating intelligent diagnosis method of Computational Intelligence (CI) and studying its application in fault feature extraction, a gear fault detection and Virtual Instrument Diagnostic System is developed by using the two hybrid programming method which combines both advantages of VC++ and MATLAB. The interface is designed by VC++ and the calculation of test data, signal processing and graphical display are completed by MATLAB. The pro-gram converted from M-file to VC++ is completed by interface software, and a various multi-functional gear fault di-agnosis software system is successfully obtained. The software system, which has many functions including the intro-duction of gear vibration signals, signal processing, graphical display, fault detection and diagnosis, monitoring and so on, especially, the ability of diagnosing gear faults. The method has an important application in the field of mechanical fault diagnosis. 展开更多
关键词 virtual instrument (VI) COMPUTATIONAL INTELLIGENCE (CI) FAULT Diagnosis Feature Extraction GEAR System
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LabVIEW-based auto-timing counts virtual instrument system with ORTEC 974 Counter/Timer 被引量:2
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作者 YAN Jie LIU Rong +6 位作者 LI Cheng JIANG Li LU Xinxin ZHU Tonghua WANG Mei WEN Zhongwei LIN Jufang 《Nuclear Science and Techniques》 SCIE CAS CSCD 2009年第5期307-311,共5页
In order to achieve the auto-timing counts measurement of nuclear radiation using ORTEC 974 Counter/Timer, an auto-timing counts virtual instrument system based on the LabVIEW virtual instrument development platform a... In order to achieve the auto-timing counts measurement of nuclear radiation using ORTEC 974 Counter/Timer, an auto-timing counts virtual instrument system based on the LabVIEW virtual instrument development platform and GPIB instrument control and transmission bus protocol is designed in this paper. By introducing software timing technique, the minimum time base of factory setting improves from 0.1 s to 0.03 s. The timing counts performance and longtime stability are also discussed in detail. The automatic data recording and saving facilitates data analysis and processing. Its real-time display and statistic function is very convenient for monitoring the nuclear radiation. 展开更多
关键词 ORTEC 原子能 放射 GPIB
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Virtual instrument for controlling and monitoring digitalized power supply in SSRF 被引量:2
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作者 TANG Jun-Long XU Rui-Nian +2 位作者 CHEN Huan-Guang SHEN Tian-Jian LI De-Ming 《Nuclear Science and Techniques》 SCIE CAS CSCD 2006年第3期129-134,共6页
The Shanghai Synchrotron Radiation Facility (SSRF) needs extremely precise power supplies for their various magnets. A digital controller is being developed for the power converters of the SSRF power supply (PS). In t... The Shanghai Synchrotron Radiation Facility (SSRF) needs extremely precise power supplies for their various magnets. A digital controller is being developed for the power converters of the SSRF power supply (PS). In the digital controller, a fully digital pulse-width modulator (PWM) directly controls the power unit insulated gate bipolar transistor (IGBT) of the PS. A program in LabVIEW language has been developed to control and monitor the digital PS via serial communication (RS232) from a PC and to modify its parameters as well. In this article, the software design of the virtual instrument for controlling and monitoring digitalized PS and its associated functions are described, and the essential elements of the program graphical main-VI and sub-VI source code are presented and explained. The com- munication protocol and the structure of the developed system are also included in this article. 展开更多
关键词 数字功率供给 虚拟工具 SSRF PWM
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Software Engineering in the Application of Virtual Instrument-Based Dynamics Testing System for UAV 被引量:3
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作者 Jing Huang Jihong Zhu Xiaming Yuan 《通讯和计算机(中英文版)》 2013年第7期926-932,共7页
关键词 动态测试系统 软件工程 虚拟仪器 无人机 LabVIEW 应用 软件开发平台 编程语言
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Application of Virtual Instrument Technology in General Test System of Launcher 被引量:1
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作者 夏晓珍 余祖俊 +1 位作者 毛建锋 左玉东 《Defence Technology(防务技术)》 SCIE EI CAS 2006年第3期194-197,共4页
关键词 虚拟手段 VXI 运载火箭 数据处理
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A Method for Modeling the Virtual Instrument Automatic Test System Based on the Petri Net 被引量:1
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作者 马敏 陈光 《Journal of Electronic Science and Technology of China》 2005年第2期157-160,共4页
Virtual instrument is playing the important role in automatic test system. This paper introduces a composition of a virtual instrument automatic test system and takes the VXIbus based a test software platform which is... Virtual instrument is playing the important role in automatic test system. This paper introduces a composition of a virtual instrument automatic test system and takes the VXIbus based a test software platform which is developed by CAT lab of the UESTC as an example. Then a method to model this system based on Petri net is proposed. Through this method, we can analyze the test task scheduling to prevent the deadlock or resources conflict. At last, this paper analyzes the feasibility of this method. 展开更多
关键词 virtual instrument automatic test system VXIBUS Petri net model system
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Virtual Instrument System for Teaching Lab
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作者 Yao, Yonggang Yao, Bowen Pan, Zhong 《Wuhan University Journal of Natural Sciences》 EI CAS 1998年第3期65-68,共4页
Virtual Instruments, which have the most brilliant prospect in the domain of instruments, are the combination of the computers and traditional instruments. According to the constructions and the characters of the Teac... Virtual Instruments, which have the most brilliant prospect in the domain of instruments, are the combination of the computers and traditional instruments. According to the constructions and the characters of the Teaching Lab Instruments, the paper introduces the principle and design of Virtual Instrument System. Meanwhile, a practical application is indicated. 展开更多
关键词 virtual instruments lab virtual instrument system modularized design
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Automatic measurement of the working band of a digital attenuator based on virtual instrument
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作者 孙天锡 王亚军 《Journal of Measurement Science and Instrumentation》 CAS 2012年第1期18-21,共4页
To measure the working band of a digital attenuator automatically,a program based on virtual instrument was carried out,using Agilent E8362B network analyzer as its measuring tool.In the program,the attenuation values... To measure the working band of a digital attenuator automatically,a program based on virtual instrument was carried out,using Agilent E8362B network analyzer as its measuring tool.In the program,the attenuation values can be automatically written into Excel table to form the frequency-attenuation curve.Finally,through analyzing the attenuation in different frequency,the best working band of the digital attenuator can be determined easily,and the whole process is automated.Compared with the traditional way of changing the measured parameters manually and recording the measured data one by one,the developed method in the paper can avoid the cumbersome manual operation and its possible errors to improve the measurement accuracy and efficiency. 展开更多
关键词 microwave attenuator working band GPIB interface virtual instrument computer automation
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Code mechanical solidification and verification in MEMS security devices
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作者 张卫平 陈文元 +2 位作者 赵小林 李胜勇 姜勇 《Journal of Shanghai University(English Edition)》 CAS 2006年第4期334-338,共5页
The virtual machine of code mechanism (VMCM) as a new concept for code mechanical solidification and verification is proposed and can be applied in MEMS (micro-electromechanical systems) security device for high c... The virtual machine of code mechanism (VMCM) as a new concept for code mechanical solidification and verification is proposed and can be applied in MEMS (micro-electromechanical systems) security device for high consequence systems. Based on a study of the running condition of physical code mechanism, VMCM's configuration, ternary encoding method, running action and logic are derived. The cases of multi-level code mechanism are designed and verified with the VMCM method, showing that the presented method is effective. 展开更多
关键词 MEMS (micro-electromechanical systems) security device code mechanical solidification and verification virtual machine of code mechanism (VMCM) ternary system.
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Reconstruction Model of Ocean Observing Complex Virtual Instrument
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作者 QIU Zhijin GUO Zhongwen +3 位作者 WANG Yu HU Tong LIU Chao LI Ting 《Journal of Ocean University of China》 SCIE CAS CSCD 2018年第5期1159-1170,共12页
With the newly proposed Global Ocean Observing Integration, ocean observing scope has been expanded from the region to the global, therefore the need of large-scale ocean observing system integration has become more a... With the newly proposed Global Ocean Observing Integration, ocean observing scope has been expanded from the region to the global, therefore the need of large-scale ocean observing system integration has become more and more urgent. Currently, ocean observing systems enabled ocean sensor networks are commonly developed by different organizations using specific technologies and platforms, which brings several challenges in ocean observing instrument (OOI) access and ocean observing system seamless integration. Furthermore, the development of ocean observing systems often suffers from low efficiency due to the complex prograrmning and debugging process. To solve these problems, a novel model, Complex Virtual Instrument (CVI) Model, is proposed. The model provides formal definitions on observing instrument description file, CVI description file, model calculation method, development model and interaction standard. In addition, this model establishes mathematical expressions of two model calculation operations, meanwhile builds the mapping relationship between observing instrument description file and CVI description file. The CVI based on the new model can achieve automatic access to different OOIs, seamless integration and communication for heterogeneous environments, and further implement standardized data access and management for the global unified ocean observing network. Throughout the development, integration and application of such CVI, the rationality and feasibility of the model have been evaluated. The results confirm that the proposed model can effectively implement heterogeneous system integration, improve development efficiency, make full usage of reusable components, reduce development cost, and enhance overall software system quality. We believe that our new model has great significance to promote the large-scale ocean observing system integration. 展开更多
关键词 ocean observing complex virtual instrument seamless integration model calculation development platform
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MEMS Test System Based on Virtual Instrument Technology
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作者 胡晓东 栗大超 +2 位作者 郭彤 胡春光 胡小唐 《Transactions of Tianjin University》 EI CAS 2007年第2期88-92,共5页
On account of the multiformity of MEMS devices, it is necessary to integrate with some optical measurement techniques for meeting static and dynamic unit test requirements. In this paper, an automated MEMS test system... On account of the multiformity of MEMS devices, it is necessary to integrate with some optical measurement techniques for meeting static and dynamic unit test requirements. In this paper, an automated MEMS test system is built of some commercially available components and instruments based on virtual instrument technology. The system is integrated with stroboscopic imaging, computer micro-vision, microscopic Mirau phase shifting interferometry, and laser Doppler vibrometer, and is used for the measurement of full-view in-plane and out-of-plane geometric parameters and periodical motions and single spot out-of-plane transient motion. The system configuration and measurement methods are analyzed, and some applications of the measurement of in-plane and out-of-plane dimensions and motions were described. The measurement accuracy of in-plane dimensions and out-of-plane dimensional is better than 0.2 um and 5 nm respectively. The resolution of measuring in-plane and out-of-plane motions is better than 15 nm and 2 nm respectively. 展开更多
关键词 MEMS optical measurement technique stroboscopic imaging virtual instrument dynamic test
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Ventilator performance evaluation system based on virtual instruments
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作者 戴文 任旭颖 林青 《Journal of Measurement Science and Instrumentation》 CAS 2012年第1期22-25,共4页
A virtual instrument system is proposed to test the performance parameters of local-ventilator installed under coal mines,which can do ventilator parameter acquisition automatically,as well as plot and analyze the ven... A virtual instrument system is proposed to test the performance parameters of local-ventilator installed under coal mines,which can do ventilator parameter acquisition automatically,as well as plot and analyze the ventilator performance curve.The whole system is designed using the virtual instrument technology combined with network technology based on Labview platform.Experimental results show that it can monitor and evaluate ventilator’s performance parameters automatically and efficiently,which provides critical information for ventilator safety under coal mine. 展开更多
关键词 virtual instrument ventilator performance evaluation remote transmission
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