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Automatic Recognition Method for Optical Measuring Instruments Based on Machine Vision 被引量:2
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作者 宋乐 林玉池 郝立果 《Transactions of Tianjin University》 EI CAS 2008年第3期202-207,共6页
Based on a comprehensive study of various algorithms, the automatic recognition of traditional ocular optical measuring instruments is realized. Taking a universal tools microscope(UTM) lens view image as an example, ... Based on a comprehensive study of various algorithms, the automatic recognition of traditional ocular optical measuring instruments is realized. Taking a universal tools microscope(UTM) lens view image as an example, a 2-layer automatic recognition model for data reading is established after adopting a series of pre-processing algorithms. This model is an optimal combination of the correlation-based template matching method and a concurrent back propagation(BP) neural network. Multiple complementary feature extraction is used in generating the eigenvectors of the concurrent network. In order to improve fault-tolerance capacity, rotation invariant features based on Zernike moments are extracted from digit characters and a 4-dimensional group of the outline features is also obtained. Moreover, the operating time and reading accuracy can be adjusted dy-namically by setting the threshold value. The experimental result indicates that the newly developed algorithm has optimal recognition precision and working speed. The average reading ratio can achieve 97.23%. The recognition method can automatically obtain the results of optical measuring instruments rapidly and stably without modifying their original structure, which meets the application requirements. 展开更多
关键词 automatic recognition optical measuring instruments template matching neural network
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National Verification Regulations and Calibration Specifications of Measuring Instruments of P.R.China in 2009
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《China Standardization》 2009年第4期69-69,共1页
关键词 JJG National Verification Regulations and Calibration Specifications of measuring instruments of P.R.China in 2009
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National Verification Regulations and Calibration Specifications of Measuring Instruments of P.R.China in 2010(2010 No.131)
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《China Standardization》 2011年第1期80-80,共1页
General Administration of Quality Supervision,Inspection and Quarantine of P.R.China has approved the following 8 national measuring verification regulations in 2010 and publicize now.
关键词 National Verification Regulations and Calibration Specifications of measuring instruments of P.R.China in 2010 No.131
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National Verification Regulations and Calibration Specifications of Measuring Instruments of P.R.China in 2008 2008 NO.35
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《China Standardization》 2008年第6期63-63,共1页
General Administration of Quality Supervision,Inspection and Quarantine of P.R.China has approved the following 11 national measuring verification regulations in 2008 and publicize now.
关键词 National Verification Regulations and Calibration Specifications of measuring instruments of P.R.China in 2008 2008 NO.35 JJG NO
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National Verification Regulations and Calibration Specifications of Measuring Instruments of P.R.China in 2008
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《China Standardization》 2008年第4期53-54,共2页
General Administration of Quality Supervision,Inspection and Quarantine of P.R.China hasapproved the following 24 national measuring verification regulations in 2008 and publicize now.
关键词 JJG National Verification Regulations and Calibration Specifications of measuring instruments of P.R.China in 2008
全文增补中
National Verification Regulations and Calibration Specifications of Measuring Instruments of P.R.China in 2008 2008 No.22
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《China Standardization》 2008年第3期54-54,共1页
General Administration of Quality Supervision,Inspection and Quarantine of P.R.China has approved the following 10 national measuring verification regulations in 2008 and publicize now.
关键词 JJG National Verification Regulations and Calibration Specifications of measuring instruments of P.R.China in 2008 2008 No.22
全文增补中
Magnetic field regression using artificial neural networks for cold atom experiments
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作者 陈子霆 黃建陶 +6 位作者 Bojeong Seo 黄明琛 Mithilesh K.Parit 何逸飞 甄浩廷 Jensen Li Gyu-Boong Jo 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第2期46-51,共6页
Accurately measuring magnetic fields is essential for magnetic-field sensitive experiments in areas like atomic,molecular,and optical physics,condensed matter experiments,and other areas.However,since many experiments... Accurately measuring magnetic fields is essential for magnetic-field sensitive experiments in areas like atomic,molecular,and optical physics,condensed matter experiments,and other areas.However,since many experiments are often conducted in an isolated environment that is inaccessible to experimentalists,it can be challenging to accurately determine the magnetic field at the target location.Here,we propose an efficient method for detecting magnetic fields with the assistance of an artificial neural network(NN).Instead of measuring the magnetic field directly at the desired location,we detect fields at several surrounding positions,and a trained NN can accurately predict the magnetic field at the target location.After training,we achieve a below 0.3%relative prediction error of magnetic field magnitude at the center of the vacuum chamber,and successfully apply this method to our erbium quantum gas apparatus for accurate calibration of magnetic field and long-term monitoring of environmental stray magnetic field.The demonstrated approach significantly simplifies the process of determining magnetic fields in isolated environments and can be applied to various research fields across a wide range of magnetic field magnitudes. 展开更多
关键词 ultracold gases trapped gases measurement methods and instrumentation
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Measurement of solidprecipitation and blowing snow: current status and challenges
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作者 PAN Rui LIU Xichuan SHI Jiayi 《Advances in Polar Science》 CSCD 2024年第3期289-302,共14页
In this article,the relevant instruments and techniques for measuring solid precipitation and blowing snow are reviewed,with a focus on the in situ instrument measurements.Moreover,a literature review and specific obs... In this article,the relevant instruments and techniques for measuring solid precipitation and blowing snow are reviewed,with a focus on the in situ instrument measurements.Moreover,a literature review and specific observation activities for solid precipitation are provided,the working principles of several instruments are introduced,and the advantages and disadvantages,measurement performance,and specific application scenarios of the instruments are evaluated.Currently,there are numerous solid precipitation measurement instruments available,and the standardization and sustainability of these measurements also need to be considered.The purpose of the review is not to be exhaustive but to provide readers with information on the current status of the development of relevant technologies and the prospects for their application in the polar regions. 展开更多
关键词 solid precipitation blowing snow measurement instruments
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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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Self-heating Probe Instrument and Method for Measuring High Temperature Melting Volume Change Rate of Material 被引量:2
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作者 WANG Junwei WANG Zhiping +1 位作者 LU Yang CHENG Bo 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2013年第2期371-376,共6页
The castings defects are affected by the melting volume change rate of material. The change rate has an important effect on running safety of the high temperature thermal storage chamber, too. But the characteristics ... The castings defects are affected by the melting volume change rate of material. The change rate has an important effect on running safety of the high temperature thermal storage chamber, too. But the characteristics of existing measuring installations are complex structure, troublesome operation and low precision. In order to measure the melting volume change rate of material accurately and conveniently, a self-designed measuring instrument, self-heating probe instrument, and measuring method are described. Temperature in heating cavity is controlled by PID temperature controller; melting volume change rate υ and molten density are calculated based on the melt volume which is measured by the instrument. Positive and negative υ represent expansion and shrinkage of the sample volume after melting, respectively. Taking eutectic LiF+CaF2 for example, its melting volume change rate and melting density at 1 123 K are -20.6% and 2 651 kg/m–3 measured by this instrument, which is only 0.71% smaller than literature value. Density and melting volume change rate of industry pure aluminum at 973 K and analysis pure NaCl at 1 123 K are detected by the instrument too. The measure results are agreed with report values. Measuring error sources are analyzed and several improving measures are proposed. In theory, the measuring errors of the change rate and molten density which are measured by the self-designed instrument is nearly 1/20-1/50 of that measured by the refitted mandril thermal expansion instrument. The self-designed instrument and method have the advantages of simple structure, being easy to operate, extensive applicability for material, relatively high accuracy, and most importantly, temperature and sample vapor pressure have little effect on the measurement accuracy. The presented instrument and method solve the problems of complicated structure and procedures, and large measuring errors for the samples with high vapor pressure by existing installations. 展开更多
关键词 high temperature volume expansion rate molten density measuring instrument measuring method
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CHARACTER OF RETROREFLECTOR’S LIGHT FIELD’S ENERGY DISTRIBUTION AND ITS MEASURING TECHNOLOGY 被引量:2
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作者 杜颖 李真 张国雄 《Transactions of Tianjin University》 EI CAS 2000年第2期117-121,共页
The formation of the retroreflected light field is introduced in the paper and the components of the retroreflected light field are analyzed.Furthermore,a deep analysis of the factors affecting energy distribution of ... The formation of the retroreflected light field is introduced in the paper and the components of the retroreflected light field are analyzed.Furthermore,a deep analysis of the factors affecting energy distribution of the retroreflected light,such as design deviation,angle of incidence,was made.The simulation of the retroreflected light field was done.Recommendation is made in detail on both the energy distribution of the retroreflected light field at different working distances and the energy distribution of the retroreflected light field at a short distance when the diverging light comes.At last,two kinds of measuring instrument for the retroreflector are introduced,one is the long tunnel measuring instrument,the other is the minitype measuring instrument based on the character of the retroreflector when the diverging light comes. 展开更多
关键词 retroreflector retroreflected light field photometric measurement measuring instrument
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Research on Solar Simulation System for Test of Solar Radiation Measuring Instrument 被引量:5
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作者 ZhengRu Zhang Guoyu +3 位作者 Lyu Wenhua Yan Jiajun Su Shi Zhang Jian 《Instrumentation》 2017年第1期3-11,共9页
Since traditional solar simulators are mainly applied to spacecraft and photovoltaic industry,they are not suitable for solar radiation measuring instrument test. Therefore,a deep research is carried out on solar simu... Since traditional solar simulators are mainly applied to spacecraft and photovoltaic industry,they are not suitable for solar radiation measuring instrument test. Therefore,a deep research is carried out on solar simulators to test of solar radiation measuring instrument,so that obtain the requirements of performance test of solar radiation measuring instrument. With a combination of the requirements for national regulations of metrological verification and performance test of pyranometer and pyrheliometer,it lays emphasis on the research of design methods for improving radiation uniformity and stability of solar simulators; it also focuses on design methods of multidimensional detection workbench,which achieves different detection of solar radiation. After practical test,solar irradiation is within Φ60 mm; irradiation non-uniformity is better than ±0.8%; instability is better than ±0.72%;rotating angle precision is better than 0.09°. Then,solar simulator is used to carry out pyranometer sensitivity test,pyranometer directional response test,pyranometer tilt response test and non-linearity test for radiation instruments. Test results showthat the solar simulator meets the testing requirements of solar radiation measuring instruments. 展开更多
关键词 Solar Simulation System Irradiation Non-uniformity Irradiation Stability Solar Radiation measuring Instrument TEST
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Application of a Soil Nutrient Measuring Instrument in Vegetable Seedling Substrate
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作者 Wang Pengcheng Zhang Jian +4 位作者 Tian Hongmei Jiang Haikun Wang Yan Wang Mingxia Fang Ling 《Meteorological and Environmental Research》 CAS 2015年第11期39-42,共4页
[Objective] The aim was to find an efficient method to measure available nitrogen, phosphorus and potassium content in vegetable seedling substrate. [ Method] The suitable dosage of leaching agent, ratio of the substr... [Objective] The aim was to find an efficient method to measure available nitrogen, phosphorus and potassium content in vegetable seedling substrate. [ Method] The suitable dosage of leaching agent, ratio of the substrate to water and leaching time for the detection of nutrient contents in the substrate by a soil nutrient measuring instrument were discussed firstly, and then the results of nutrient contents measured by the soil nutrient measuring instrument were compared with that by conventional approaches. [ Result] In compadson with the conventional methods, the av- erage content of available nitrogen measured by the soil nutrient measuring instrument was slightly higher, while the average content of available phosphorus measured by the instrument was lower; the average content of available potassium measured by the instrument was close to that by the conventional method. [ Conclusion] This study could provide us a new method to detect available nitrogen, phosphorus and potassium content in seedling substrate efficiently. 展开更多
关键词 Soil nutrient measuring instrument Seedling substrate Available nitrogen Available phosphorus Available potassium Measurement method
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Implementation of Vibrancy Awaking Pressure Measuring Instrument for Single Hydraulic Prop
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作者 郑丰隆 王丽玲 +2 位作者 朱凯 陈洋 姚文静 《Journal of Measurement Science and Instrumentation》 CAS 2011年第1期92-95,共4页
An instnmaent awakened by means of vibration for single hydraulic prop pressame measuring is described in this paper. The principle and implementation of this metlmd are introduced in detail. The instnznent uses the h... An instnmaent awakened by means of vibration for single hydraulic prop pressame measuring is described in this paper. The principle and implementation of this metlmd are introduced in detail. The instnznent uses the hgh-perftmnance single chip C8051F310 as its MCU and vibration sensor as its awaking device. It has such advantages as small vohane and low power consmnption, and moreover it could resolve the problem that traditional pressure measming instrument on single hydraulic prop can't be used in coal mine. 展开更多
关键词 single hydraulic trop vibration sensor low power cansumption pressure measuring instrument
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A novel wide-range precision instrument for measuring three-dimensional surface topography
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作者 杨旭东 《Journal of Chongqing University》 CAS 2008年第1期52-57,共6页
We developed a measuring instrument that had wide range, high precision, small measuring touch force. The instrument for three-dimensional (3D) surface topography measurement was composed of a high precision displacem... We developed a measuring instrument that had wide range, high precision, small measuring touch force. The instrument for three-dimensional (3D) surface topography measurement was composed of a high precision displacement sensor based on the Michelson interference principle, a 3D platform based on vertical scanning, a measuring and control circuit, and an industrial control computer. It was a closed loop control system, which changed the traditional moving stylus scanning style into a moving platform scanning style. When the workpiece was measured, the lever of the displacement sensor returned to the balanced position in every sample interval according to the zero offset of the displacement sensor. The non-linear error caused by the rotation of the lever was, therefore, very small even if the measuring range was wide. The instrument can measure the roughness and the profile size of a curved surface. 展开更多
关键词 instrument circuit surface topography measurement error wide range precision instrument displacement sensor 3D platform
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Gold Measuring Instrument
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《China's Foreign Trade》 1995年第2期37-37,共1页
The China Energy Science Research Institute has developed an instrument to check the colour of gold, which can quickly measure the content of gold and silver ingots, chains, ornaments and placer gold and does not harm... The China Energy Science Research Institute has developed an instrument to check the colour of gold, which can quickly measure the content of gold and silver ingots, chains, ornaments and placer gold and does not harm the objects. It is an ideal apparatus for gold and silver shops and processing departments. Composed of a main machine, a computer and a printer, the instrument shows at once the content through graphs and a print-out of figures. It is easy to operate and highly accurate. 展开更多
关键词 Gold measuring Instrument
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A CAD-based inspection planning strategy for video measuring instrument
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作者 LU Rong-sheng SHI Yan-qiong XIA Rui-xue CHEN Lin 《Computer Aided Drafting,Design and Manufacturing》 2012年第2期78-83,共6页
A CAD-based inspection planning strategy for video measuring instrument is proposed to improve manufacturing effec- tiveness. The system consists of a video probe that enables itself to inspect a work piece based on a... A CAD-based inspection planning strategy for video measuring instrument is proposed to improve manufacturing effec- tiveness. The system consists of a video probe that enables itself to inspect a work piece based on a CAD model. The measurement software includes CAIP module and MDP module. The CAIP module is developed based on a CAD development platform whose kernel is the Open CASCADE. The entire system was tested, and relevant examples show that the system can accomplish automatic inspection planning task for common parts efficiently. 展开更多
关键词 video measuring instrument CAD-based inspection planning
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On Quality Evaluation and Analysis of Metrological Verification and Detection
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作者 Meng Xiaobo 《Journal of Environmental Science and Engineering(B)》 2022年第1期24-30,共7页
With the rapid development of China’s economy and society,under the existing economic system,measurement work is of great significance to promote market development and improve people’s living standards.The quality ... With the rapid development of China’s economy and society,under the existing economic system,measurement work is of great significance to promote market development and improve people’s living standards.The quality evaluation of testing work is an important means to ensure the accuracy of measurement.Based on the analysis of several factors affecting the quality of measurement work,this paper takes the ionizing radiation monitoring quality as an example,and makes a concrete exposition on the evaluation and analysis of the quality of metrological verification work. 展开更多
关键词 Metrological verification test the quality of work measuring instruments ionization chamber
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生产率损失测量工具的比较研究 被引量:2
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作者 周沛宇 席晓宇 《中国卫生资源》 北大核心 2022年第5期570-576,共7页
目的 比较可用于卫生技术评估中的生产率损失测量工具,厘清可用于卫生技术评估中的生产率损失测量工具的应用条件,以期为相关研究者在选择生产率损失的测量工具时提供参考。方法 检索PubMed、Web of Science、中国知网、万方、维普等中... 目的 比较可用于卫生技术评估中的生产率损失测量工具,厘清可用于卫生技术评估中的生产率损失测量工具的应用条件,以期为相关研究者在选择生产率损失的测量工具时提供参考。方法 检索PubMed、Web of Science、中国知网、万方、维普等中外数据库,检索时间从数据库建库至2021年11月,由2名研究者按照纳入与排除标准独立筛选文献、识别生产率损失测量工具、提取资料。结果 共识别出5种可用于卫生技术评估领域中的生产率损失测量工具,包括工作能力和活动受损量表(work productivity activity and impairment,WPAI)、工作能力局限调查问卷(work limitations questionnaire,WLQ)、健康与工作绩效问卷(Health and Work Performance Questionnaire,HPQ)、损失产能的估值(Valuation of Lost Productivity Questionnaire,VOLP)和医疗技术评估研究院(Institute for Medical Technology Assessment,IMTA)的生产力成本问卷(IMTA Productivity Questionnaire,IPCQ)。其中WPAI和WLQ是测量属性证据最为充足的工具;VOLP是成本涵盖最全的工具;WLQ是数据敏感性最强的工具;IPCQ是货币转化方法最多的工具;WPAI是获取使用最方便的工具。结论 对于卫生技术评估中的生产率损失测量的标准工具尚未存在统一共识,研究者可根据自身研究选取生产率损失测量工具。 展开更多
关键词 生产率损失productivity loss 间接成本indirect cost 测量工具measure instrument 卫生技术评估health technology assessment
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Methodological quality(risk of bias) assessment tools for primary and secondary medical studies: What are they and which is better? 被引量:44
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作者 Lin-Lu Ma Yun-Yun Wang +3 位作者 Zhi-Hua Yang Di Huang Hong Weng Xian-Tao Zeng 《Military Medical Research》 SCIE CAS CSCD 2020年第3期359-370,共12页
Methodological quality(risk of bias)assessment is an important step before study initiation usage.Therefore,accurately judging study type is the first priority,and the choosing proper tool is also important.In this re... Methodological quality(risk of bias)assessment is an important step before study initiation usage.Therefore,accurately judging study type is the first priority,and the choosing proper tool is also important.In this review,we introduced methodological quality assessment tools for randomized controlled trial(including individual and cluster),animal study,non-randomized interventional studies(including follow-up study,controlled before-and-after study,before-after/pre-post study,uncontrolled longitudinal study,interrupted time series study),cohort study,case-control study,cross-sectional study(including analytical and descriptive),observational case series and case reports,comparative effectiveness research,diagnostic study,health economic evaluation,prediction study(including predictor finding study,prediction model impact study,prognostic prediction model study),qualitative study,outcome measurement instruments(including patient-reported outcome measure development,content validity,structural validity,internal consistency,cross-cultural validity/measurement invariance,reliability,measurement error,criterion validity,hypotheses testing for construct validity,and responsiveness),systematic review and meta-analysis,and clinical practice guideline.The readers of our review can distinguish the types of medical studies and choose appropriate tools.In one word,comprehensively mastering relevant knowledge and implementing more practices are basic requirements for correctly assessing the methodological quality. 展开更多
关键词 Methodological quality Risk of bias Quality assessment Critical appraisal Methodology checklist Appraisal tool Observational study Qualitative study Interventional study Outcome measurement instrument
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