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Study on a conical bearing for acceleration-sensitive equipment
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作者 Pang Hui Xu Wen +1 位作者 Dai Junwu Jiang Tao 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2024年第1期103-128,共26页
Seismic isolation effectively reduces seismic demands on building structures by isolating the superstructure from ground vibrations during earthquakes.However,isolation strategies give less attention to acceleration-s... Seismic isolation effectively reduces seismic demands on building structures by isolating the superstructure from ground vibrations during earthquakes.However,isolation strategies give less attention to acceleration-sensitive systems or equipment.Meanwhile,as the isolation layer’s displacement grows,the stiffness and frequency of traditional rolling and sliding isolation bearings increases,potentially causing self-centering and resonance concerns.As a result,a new conical pendulum bearing has been selected for acceleration-sensitive equipment to increase self-centering capacity,and additional viscous dampers are incorporated to enhance system damping.Moreover,the theoretical formula for conical pendulum bearings is supplied to analyze the device’s dynamic parameters,and shake table experiments are used to determine the proposed device’s isolation efficiency under various conditions.According to the test results,the newly proposed devices have remarkable isolation performance in terms of minimizing both acceleration and displacement responses.Finally,a numerical model of the isolation system is provided for further research,and the accuracy is demonstrated by the aforementioned experiments. 展开更多
关键词 seismic isolation acceleration-sensitive equipment the conical pendulum bearing shake table tests isolation performance numerical model
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Design on Model-based Visualization System for Civil Aircraft Airborne Equipment Identification Test
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作者 ZHANG Juan MA Xiaojun A Dina 《International Journal of Plant Engineering and Management》 2024年第3期167-184,共18页
To meet the needs of complex system equipment testing and realize the visual management of different test projects,this article establishes a test project management system based on the actual situation of aviation eq... To meet the needs of complex system equipment testing and realize the visual management of different test projects,this article establishes a test project management system based on the actual situation of aviation equipment testing system and the concept of big data,using visual data management and analysis techniques.This system solves the comprehensive management of multi-type test projects.Combined with the actual engineering verification process,it can be found that the system can realize the visual management of test projects and effectively ensure the smooth completion of the identification test project of a certain type of aircraft′s complex system. 展开更多
关键词 onboard equipment qualification testing visual system
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Modeling and Simulation for Complex Repairable System with Built-in Test Equipment 被引量:1
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作者 吕学志 于永利 +1 位作者 张柳 任帆 《Defence Technology(防务技术)》 SCIE EI CAS 2011年第2期119-125,共7页
In order to research the effects of built-in test(BIT) on the system and select BITand test strategy,the complex repairable systems with BITequipment are modeled and simulated by using Simulink.Based on the model,the ... In order to research the effects of built-in test(BIT) on the system and select BITand test strategy,the complex repairable systems with BITequipment are modeled and simulated by using Simulink.Based on the model,the influences of different built-in test equipments,maintenance time and error probabilities on the system usability are evaluated.The simulation results showthat they effect on the system differently.The simulation method of complex system based on Simulink provides a technique approach to research the effects of BITon the system and select BITand test strategy. 展开更多
关键词 computer application complex system built-in test equipment SIMULinK
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Research of in-situ hydraulic test method by using double packer equipment 被引量:1
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作者 JI Rui-li ZHANG Ming +3 位作者 SU Rui GUO Yong-hai ZHOU Zhi-chao LI Jie-biao 《Journal of Groundwater Science and Engineering》 2016年第1期41-51,共11页
Double packer equipment for hydraulic test can be used to measure pressure of test zone directly, and it is frequently used to perform many kinds of hydraulic tests and take groundwater sample from borehole. The test ... Double packer equipment for hydraulic test can be used to measure pressure of test zone directly, and it is frequently used to perform many kinds of hydraulic tests and take groundwater sample from borehole. The test method of this equipment mainly includes the test design, implementation, interpretation and synthetic analysis. By adopting the double packer equipment for hydraulic test, the parameter distribution of rock permeability along borehole can be acquired, as well as the connectivity, water conductivity and water bearing capacity of the disclosed structure and the chemical characteristics of the deep groundwater. It is a necessary method for the research and evaluation of the complex hypotonicity terrace site selection under geological conditions. This method is not only suitable for the geological disposal of high level radioactive waste, but also can be used in the site selection of underground facilities such as storage of petroleum and carbon dioxide. Meanwhile, it has a good application prospect in other hydrogeological investigation fields. 展开更多
关键词 Lower PERMEABILITY rock DOUBLE PAcKER equipment BOREHOLE in-SITU test method
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Study on rate ripple and its adaptive suppression method in inertia guidance test equipment
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作者 张元生 徐国柱 刘樾 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2007年第1期144-148,共5页
This paper discusses causes of the rate ripple in inertia guidance test equipment IGET, systematically analyses their effects an the rate ripple in IGTE. The analysis result shows: The rate ripple caused by the perio... This paper discusses causes of the rate ripple in inertia guidance test equipment IGET, systematically analyses their effects an the rate ripple in IGTE. The analysis result shows: The rate ripple caused by the periodic errors of inductosyn and angular encoder is higher at high speed than that caused by magnetic ripple torque and friction torque, and it cannot be eliminated by adjusting control parameters of the system. And based on the nonlinear adaptive control system theory, the paper puts forward a new control system scheme to eliminate the rate ripple caused by the periodic errors of inductosyn and angular encoder, develops the adaptive control rules and makes simulation and test. Experimental result shows a significant improvement on those tables for the period disturbs under the system scheme designed. By this plan, with the input of rate 200°/s, the rate ripple falls from 5°/s to 0. 4°/s within about 6s adaptive adjustment time, being a twelfth of before adaptation, which can not be reached by common classical controls. The experimental results conform with the simulation, which proves the validity and practicability of the plan. 展开更多
关键词 rate ripple period disturb adaptive control nonlinear system inertia guidance test equipment
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Machines and Testing Equipment
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《China's Refractories》 CAS 2007年第4期54-55,共2页
National Quality Supervision & Inspection Center for Refractories Business scope: Selective examination for national quality supervision; Identification of production license; Arbitration inspection and technical ac... National Quality Supervision & Inspection Center for Refractories Business scope: Selective examination for national quality supervision; Identification of production license; Arbitration inspection and technical achievements evaluation; Commodities inspection and otherquality inspections . 展开更多
关键词 test Machines and testing equipment
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Application of Using Standard Equipment for Dental Scaler Tip Testing according to ISO 18397
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作者 Chompoonoot Hirunyapruk Tassanai Sanponpute 《Journal of Mechanics Engineering and Automation》 2020年第2期52-59,共8页
The objective of this work was to study the use of standard equipment in amplitude and frequency tests of dental scaler tip according to ISO 18397.Four types of standard equipment:a laser displacement sensor,a microsc... The objective of this work was to study the use of standard equipment in amplitude and frequency tests of dental scaler tip according to ISO 18397.Four types of standard equipment:a laser displacement sensor,a microscope,a tachometer,and an ultrasonic frequency meter,were experimentally investigated to test a tip.The standard laser displacement sensor and the standard microscope were used to test the unloaded amplitude of the scaler tip.It was found that two types of standard equipment were able to measure the unloaded amplitude of the tip.The standard microscope was also employed for the loaded amplitude test.This test was performed by pressing the scaler tip with a load of 1 N,which was measured by a load cell set.The peak-to-peak amplitude found from the test was 116.7 m.The frequency test of the scaler tip was conducted using the standard laser displacement sensor,the tachometer and the ultrasonic frequency meter.All three types of standard equipment were found to be able to test the frequency of the tip without cooling liquid.Nevertheless,only the standard tachometer was capable of measuring the frequency of the tip with cooling liquid applied. 展开更多
关键词 Dental scaler tip ISO 18397 testinG standard equipment
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Design of multi-section luffing apple pruning equipment and cutting test of the key components
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作者 Siyuan Tong Wenbin Li +2 位作者 Yaxiong Wang Lei Zhang Feng Kang 《International Journal of Agricultural and Biological Engineering》 SCIE 2024年第1期109-117,共9页
In order to reduce the labor intensity and improve the efficiency of pruning,this study designed a multi-section luffing apple pruning equipment suitable for apple orchards in hilly and mountainous areas of China.In t... In order to reduce the labor intensity and improve the efficiency of pruning,this study designed a multi-section luffing apple pruning equipment suitable for apple orchards in hilly and mountainous areas of China.In the essay,the structure and working principle of the equipment are expounded,the cutter was analyzed,and the parameters were determined.Using the self-made test bench to simulate the field experiment,this study selected the ratio of cutting speed to feeding speed and feeding speed as the influencing factors and took the cut-off rate,cutting efficiency and cutting power as the objectives to carry out single factor experiment and quadratic regression orthogonal experiment.The test results show that the cutting power increases with the increase of ratio of cutting speed to feeding speed,and the cut-off rate and cutting efficiency first increase and then decrease.As the feeding speed increases,the cutting efficiency and power increase,and the cut-off rate decreases.When the cutoff rate was greater than 80%,the optimal combination of operating parameters was the feeding speed of 0.55 m/s and ratio of cutting speed to feeding speed of 1.29.Under this combination,the cut-off rate was 84.9%,the cutting efficiency was 13.1,and the cutting power was 175.7 W.The error between the predicted target value of the model and the average measured target value was less than 7%,so the test results are reliable.According to the obtained optimal operating parameters,the actual cutting experiment of the pruning equipment in the field was carried out,and the cutting rate was 96.3%,which meet the design requirements.This study can also meet the needs of mechanized pruning of fruit trees with different crown shapes,improve the applicability of pruning equipment,and provide support for the development of mechanized pruning equipment in China. 展开更多
关键词 APPLE pruning equipment cutting test optimal parameters regression analysis
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Development of in-situ testing equipment of rock and soil thermophysical properties
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作者 Qinghua WANG Youhong SUN Qiang LI 《Global Geology》 2008年第4期237-241,共5页
A mobile in-situ testing equipment used to detect geotechnical thermophysical properties was developed. The equipment is composed of a heat pump, frequency pumps, an electric tee joint regulator valve, some sensors, a... A mobile in-situ testing equipment used to detect geotechnical thermophysical properties was developed. The equipment is composed of a heat pump, frequency pumps, an electric tee joint regulator valve, some sensors, an electric control system, data acquisition and control system, which can do tests under the condition of extracting and storing subsurface heat. Applying the line source and the cylinder source heat transfer model, and combining the parameters estimation, the average thermophysieal property parameters of rock and soil will be calculated, which provides the basis for designing the ground source heat pump systems. 展开更多
关键词 thermophysical properties field testing equipment data processing systems heat transfer model
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Making your own Automatic Test Equipment has never been easier
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作者 WK Bohannon 《电子与封装》 2005年第4期23-24,4,共3页
Using Planet ATE's SOC 'all-in-one' pin electronics solutions it is easy to make your owntester, ATE or to modify load boards for more advanced test capabilities.
关键词 ATE SOc PMU 测试要求 集成电路
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基于ATML标准的SCATS在机载电子系统通用自动测试设备中的应用
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作者 吴国宝 宋帆 +1 位作者 曾俊华 游洪顺 《计算机测量与控制》 2024年第3期340-345,352,共7页
SCATS是一款由成都天奥测控技术有限公司开发的,基于最新AMTL标准的面向信号的国产自动测试程序集开发软件;ATML标准的显著特征,便是采用了可扩展标记语言(XML),以实现测试信息描述的标准化和测试信息的可交互,通过生成的基于ATML标准... SCATS是一款由成都天奥测控技术有限公司开发的,基于最新AMTL标准的面向信号的国产自动测试程序集开发软件;ATML标准的显著特征,便是采用了可扩展标记语言(XML),以实现测试信息描述的标准化和测试信息的可交互,通过生成的基于ATML标准的描述文档,实现对被测对象的特征信息、测试信号、测试路径、测试策略、故障诊断等内容的表述,进而实现通用测试设备的通用化设计,有效克服了传统面向信号的测试设备测试程序集开发软件存在的语言形式复杂、信号模型少、软件架构开放性差等不足;SCATS软件采用纯中文开发界面,测试程序集采用无代码开发,软件界面友好、可读性强,大大降低了测试程序集开发人员的技术门槛,内置信号模型丰富可满足现代机载电子系统测试需求;通过在机载电子系统通用测试设备中的应用表明,使用SCATS软件开发的机载电子系统测试程序集具有开发速度快、故障定位准确、通用性和可移植性好等特点。 展开更多
关键词 ATML ScATS 机载电子系统 测试设备
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水文测验中定点式ADCP设备运行维护及故障处理方法
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作者 黄炜 张晨旭 《江苏水利》 2024年第3期66-68,72,共4页
自动流量测验设备在水文测验中具有时效强、量程大、安全性高等优势,定点式ADCP是目前较为常见的实时在线自动流量测验设备,其设备运行状况直接决定了测验精度、测验稳定性以及测验长效性。结合近年来水文测验中的应用实例,详细阐述定点... 自动流量测验设备在水文测验中具有时效强、量程大、安全性高等优势,定点式ADCP是目前较为常见的实时在线自动流量测验设备,其设备运行状况直接决定了测验精度、测验稳定性以及测验长效性。结合近年来水文测验中的应用实例,详细阐述定点式ADCP测验设备运行维护的要点,并对常见故障及处理方法进行分析。 展开更多
关键词 流量测验 ADcP设备 故障处理 运行维护
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Experimental and analytical studies on multiple tuned mass dampers for seismic protection of porcelain electrical equipment 被引量:9
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作者 Bai Wen Dai Junwu +2 位作者 Zhou Huimeng Yang Yongqiang Ning Xiaoqing 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2017年第4期803-813,共11页
Porcelain electrical equipment (PEE), such as current transformers, is critical to power supply systems, but its seismic performance during past earthquakes has not been satisfactory. This paper studies the seismic ... Porcelain electrical equipment (PEE), such as current transformers, is critical to power supply systems, but its seismic performance during past earthquakes has not been satisfactory. This paper studies the seismic performance of two typical types of PEE and proposes a damping method for PEE based on multiple tuned mass dampers (MTMD). An MTMD damping device involving three mass units, named a triple tuned mass damper (TTMD), is designed and manufactured. Through shake table tests and finite element analysis, the dynamic characteristics of the PEE are studied and the effectiveness of the MTMD damping method is verified. The adverse influence of MTMD redundant mass to damping efficiency is studied and relevant equations are derived. MTMD robustness is verified through adjusting TTMD control frequencies. The damping effectiveness of TTMD, when the peak ground acceleration far exceeds the design value, is studied. Both shake table tests and finite element analysis indicate that MTMD is effective and robust in attenuating PEE seismic responses. TTMD remains effective when the PGA far exceeds the design value and when control deviations are considered. 展开更多
关键词 current transformer DAMPinG porcelain electrical equipment finite element analysis multiple tuned massdampers shake table test
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Random Vibration Analysis of the Electronic Equipment Cabinet 被引量:3
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作者 LIU Yanping~1 LIU Dongqing~2 1.Key Laboratory of Condition Monitoring and Control for Power Plant Equipment of Ministry of Education,North China Electric Power University,Beijing 102206 ,China 2.Beijing University of Science and Technology,Beijing 100083,China 《武汉理工大学学报》 CAS CSCD 北大核心 2006年第S2期709-713,共5页
In order to understand the vibration characteristic of system structure of electronic equipment cabinet within the particular vibration frequency,the finite element analysis software-ANSYS is used to simulate the test... In order to understand the vibration characteristic of system structure of electronic equipment cabinet within the particular vibration frequency,the finite element analysis software-ANSYS is used to simulate the tests of random vibrations of the cabinet system and obtain the isopleths graph of deformation and stress of the cabinet.It can confirm maximum of deformation and stress of the cabinet and position happened.Through more analysis of the frequency response curve,which can confirm harm- ful consequences random vibrations caused and weak link of the cabinet structure.The numerical simulation results are in good a- greement with the experimental results.It shows that this research provides an efficient method for the anti-seismic design and the dynamic optimization design. 展开更多
关键词 RANDOM vibrations test vibration cHARAcTERISTIc NUMERIcAL simulation FinITE ELEMENT analysis electronic equipment cABinET ANSYS software
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Optimization of dynamic sequential test strategy for equipment health management 被引量:3
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作者 Shuming Yang Jing Qiu Guanjun Liu Peng Yang 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2012年第1期71-77,共7页
Testing is the premise and foundation of realizing equipment health management (EHM). To address the problem that the static periodic test strategy may cause deficient test or excessive test, a dynamic sequential te... Testing is the premise and foundation of realizing equipment health management (EHM). To address the problem that the static periodic test strategy may cause deficient test or excessive test, a dynamic sequential test strategy (DSTS) for EHM is presented. Considering the situation that equipment health state is not completely observable in reality, a DSTS optimization method based on partially observable semi-Markov decision pro- cess (POSMDP) is proposed. Firstly, an equipment health state degradation model is constructed by Markov process, and the control limit maintenance policy is also introduced. Secondly, POSMDP is formulated in great detail. And then, POSMDP is converted to completely observable belief semi-Markov decision process (BSMDP) through belief state. The optimal equation and the corresponding optimal DSTS, which minimize the long-run ex- pected average cost per unit time, are obtained with BSMDP. The results of application in complex equipment show that the proposed DSTS is feasible and effective. 展开更多
关键词 equipment health management (EHM) dynamic sequential test strategy (DSTS) partially observable semi-Markov decision process (POSMDP) optimal equation.
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Automatic Extraction Method of Weld Weak Defect Features for Ultra-High Voltage Equipment
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作者 Guanghua Zheng Chaolin Luo +3 位作者 Mengen Shen Wanzhong Lv Wenbo Jiang Weibo Yang 《Energy Engineering》 EI 2023年第4期985-1000,共16页
To solve the problems of low precision of weak feature extraction,heavy reliance on labor and low efficiency of weak feature extraction in X-ray weld detection image of ultra-high voltage(UHV)equipment key parts,an au... To solve the problems of low precision of weak feature extraction,heavy reliance on labor and low efficiency of weak feature extraction in X-ray weld detection image of ultra-high voltage(UHV)equipment key parts,an automatic feature extraction algorithm is proposed.Firstly,the original weld image is denoised while retaining the characteristic information of weak defects by the proposed monostable stochastic resonance method.Then,binarization is achieved by combining Laplacian edge detection and Otsu threshold segmentation.Finally,the automatic identification of weld defect area is realized based on the sequential traversal of binary tree.Several characteristic analysis dimensions are established for weld defects of UHV key parts,including defect area,perimeter,slenderness ratio,duty cycle,etc.The experiment using theweld detection image of the actual production site shows that the proposedmethod can effectively extract theweak feature information ofweld defects and further provide reference for decision-making. 展开更多
关键词 UHV equipment WELD nondestructive testing weak feature extraction
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CINRAD/SA天气雷达光纤链路测试工装系统设计与实现
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作者 姚雷 朱毅 +1 位作者 吴嘉伟 储晨曦 《气象水文海洋仪器》 2023年第4期107-111,共5页
针对当前CINRAD/SA天气雷达伺服系统中光纤链路故障率较高的问题,文章设计了一套天气雷达光纤链路测试工装系统。文章详细研究了测试工装系统的电路组成和角码时序程序流程,通过测试和判断实现对CINRAD/SA天气雷达中光纤链路的测试和故... 针对当前CINRAD/SA天气雷达伺服系统中光纤链路故障率较高的问题,文章设计了一套天气雷达光纤链路测试工装系统。文章详细研究了测试工装系统的电路组成和角码时序程序流程,通过测试和判断实现对CINRAD/SA天气雷达中光纤链路的测试和故障诊断。借助该测试工装系统进行伺服系统相关组件的快速故障诊断定位,可缩短维修时间,提高维修效率,该系统能够成为天气雷达省级维修测试平台的重要组成部分。 展开更多
关键词 cinRAD/SA天气雷达 光纤链路 测试工装 故障诊断
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Predicting stability of integrated circuit test equipment using upper side boundary values of normal distribution
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作者 Zhan Wenfa Hu Xinyi +3 位作者 Zheng Jiangyun Yu Chuxian Cai Xueyuan Zhang Lihua 《The Journal of China Universities of Posts and Telecommunications》 EI CSCD 2024年第2期85-93,共9页
In response to the growing complexity and performance of integrated circuit(IC),there is an urgent need to enhance the testing and stability of IC test equipment.A method was proposed to predict equipment stability us... In response to the growing complexity and performance of integrated circuit(IC),there is an urgent need to enhance the testing and stability of IC test equipment.A method was proposed to predict equipment stability using the upper side boundary value of normal distribution.Initially,the K-means clustering algorithm classifies and analyzes sample data.The accuracy of this boundary value is compared under two common confidence levels to select the optimal threshold.A range is then defined to categorize unqualified test data.Through experimental verification,the method achieves the purpose of measuring the stability of qualitative IC equipment through a deterministic threshold value and judging the stability of the equipment by comparing the number of unqualified data with the threshold value,which realizes the goal of long-term operation monitoring and stability analysis of IC test equipment. 展开更多
关键词 K-means clustering algorithm the upper side boundary of normal distribution THRESHOLD integrated circuit(Ic)test equipment stability analysis
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Implementation of a Subjective Visual Vertical and Horizontal Testing System Using Virtual Reality
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作者 Sungjin Lee Min Hong +1 位作者 Hongly Va Ji-Yun Park 《Computers, Materials & Continua》 SCIE EI 2021年第6期3669-3679,共11页
Subjective visual vertical(SVV)and subjective visual horizontal(SVH)tests can be used to evaluate the perception of verticality and horizontality,respectively,and can aid the diagnosis of otolith dysfunction in clinic... Subjective visual vertical(SVV)and subjective visual horizontal(SVH)tests can be used to evaluate the perception of verticality and horizontality,respectively,and can aid the diagnosis of otolith dysfunction in clinical practice.In this study,SVV and SVH screen version tests are implemented using virtual reality(VR)equipment;the proposed test method promotes a more immersive feeling for the subject while using a simple equipment configuration and possessing excellent mobility.To verify the performance of the proposed VR-based SVV and SVH tests,a reliable comparison was made between the traditional screen-based SVV and SVH tests and the proposed method,based on 30 healthy subjects.The average results of our experimental tests on the VR-based binocular SVV and SVH equipment were−0.15◦±1.74 and 0.60◦±1.18,respectively.The proposed VR-based method satisfies the normal tolerance for horizontal or vertical lines,i.e.,a±3◦error,as defined in previous studies,and it can be used to replace existing test methods. 展开更多
关键词 Subjective visual vertical subjective visual horizontal virtual reality UNITY3D FOVE HMD vestibular function tests diagnostic equipment
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带包覆层承压设备的PECT应用研究
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作者 孙杰 陈俊仰 +3 位作者 付跃文 李绪丰 王亚星 宾伟淇 《机电工程技术》 2024年第10期96-100,共5页
特种设备如压力容器、压力管道等,在石油、精细化工、火电、核电等行业得到了大规模应用;其安全健康运行对于保障装置的稳定生产具有重要作用。采用脉冲涡流检测(PECT)技术可对设备包覆层下存在的内外壁腐蚀缺陷进行快速在线检测,对于... 特种设备如压力容器、压力管道等,在石油、精细化工、火电、核电等行业得到了大规模应用;其安全健康运行对于保障装置的稳定生产具有重要作用。采用脉冲涡流检测(PECT)技术可对设备包覆层下存在的内外壁腐蚀缺陷进行快速在线检测,对于保障核心设备的本质安全有着重要意义。介绍了带包覆层承压特种设备的脉冲涡流检测应用研究背景,并对带包覆层承压特种设备PECT技术原理进行了介绍。通过对比试验,对PECT检测探头结构进行了深入研究,总结出U形磁芯探头具有更加良好的检测灵敏度;通过试验观察,相邻金属构件和金属保护层搭接位置是PECT结果主要的干扰因素,通过对探头施加金属屏蔽层可有效滤除周边金属构件干扰,同时发现铁磁性材料的金属保护层搭接的干扰信号难以去除;现场实际应用案例,证明了PECT技术对带包覆层承压设备腐蚀具有良好的适用性。 展开更多
关键词 包覆层 承压设备 腐蚀缺陷 在线检测 脉冲涡流检测
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