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Evaluation Test Research of DR Inspection System for Circumferential Welds in Long Distance Pipeline
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作者 WANG Changjiang WANG Xue +4 位作者 ZHANG Shimin ZHAO Yan LYU Xinyu ZHONG Qian ZHOU Guangyan 《材料导报》 EI CAS CSCD 北大核心 2024年第22期223-229,共7页
Digital radiographic(DR)testing equipment has been widely promoted and applied in the inspection of circumferential welds in oil and gas pipelines.In order to establish a comprehensive quality control system for digit... Digital radiographic(DR)testing equipment has been widely promoted and applied in the inspection of circumferential welds in oil and gas pipelines.In order to establish a comprehensive quality control system for digital radiographic testing and fully evaluate the integrated system inspection ability of equipment,personnel,and processes,a scientific and standardized evaluation method to the system is very necessary.Here investigates the precedents of relevant non-destructive testing evaluation methods at home and abroad,considers the testing characteristics of DR equipment,develops a complete set of DR testing system evaluation procedures.It deeply studies the adaptability methods of program processes from defect production to slicing processing and data statistical calculation for digital radiographic testing evaluation.To check the repeatability and reliability of the detectable system,five process welds with 200 real metallographic defects were fabricated in the laboratory.From the detected results,the DR system has good repeatability in image quality,and the detectable defect size reaches 0.85 mm under achieving 90%detection probability at a confidence level of 95%,the error of detected defect length is±2 mm,and the error of detected defect localization is±5 mm.The qualitative and quantitative detection of defects are accurate and reliable.The test further confirmed the reliable detection ability of the DR detection system,and fully validated the scientific and practical evaluation method designed.The research on the evaluation test method can serve as an important link in the quality control system for the on-site application of digital ray equipment in long-distance pipelines.The designed program,test,and evaluation content can serve as an important basis for the formulation of relevant specifications or standards. 展开更多
关键词 digital ray evaluation test REPEATABILITY RELIABILITY
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A virtual test and evaluation method for fully mechanized mining production system with diferent smart levels
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作者 Jiacheng Xie Fuxiang Ge +1 位作者 Tao Cui Xuewen Wang 《International Journal of Coal Science & Technology》 EI CAS CSCD 2022年第3期151-170,共20页
A smart fully mechanized coal mining working face is comprised of various heterogeneous equipment that work together in unknown coal seam environments.The goal is to form a smart operational system with comprehensive ... A smart fully mechanized coal mining working face is comprised of various heterogeneous equipment that work together in unknown coal seam environments.The goal is to form a smart operational system with comprehensive perception,decisionmaking,and control.This involves many work points and complex coupling relationships,indicating it needs to be performed in stages and coordinated to address key problems in all directions and along multiple points.However,there are no existing unifed test or analysis tools.Therefore,this study proposed a virtual test and evaluation method for a fully mechanized mining production system with diferent smart levels.This is based on the concept of“real data processing–virtual scene construction–setting key information points–virtual operation and evaluation.”The actual operational data for a specifc working face geology and equipment were reasonably transformed into a visual virtual scene through a movement relationship model.The virtual operations and mining conditions of the working face were accurately reproduced.Based on the sensor and execution error analyses for diferent smart levels,the input interface for sensing,decision-making,and control was established for each piece of equipment,and an operation evaluation system was constructed.The system comprehensively simulates and tests the key points of sensing decision-making and control with various smart levels.The experimental results showed that the virtual scene constructed based on actual operational data has a high simulation degree.Users can simulate,analyze,and evaluate the overall operations of the smart mining 2.0–4.0 working face by inputting key information.The future direction for the smart development of fully mechanized mining is highlighted. 展开更多
关键词 Smart mining Mining robot Digital twin Virtual simulation test and evaluation
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Question Bank Construction and Test Paper Auto-generation System Implementation Based on Delphi
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《International English Education Research》 2014年第1期4-6,共3页
Nowadays, the computer is increasingly popular, and college examination is developing in the direction of traditional examination means to automation and intelligence ones gradually, all these make it inevitable to co... Nowadays, the computer is increasingly popular, and college examination is developing in the direction of traditional examination means to automation and intelligence ones gradually, all these make it inevitable to construct question bank for courses, and to generate test paper using computers. This paper uses the Delphi technique, to make improvements to existing components, combining with VBA programming, and use of SQL Server to implement the question bank management and test paper auto-generation system, which could generate test paper in Word Document. A large number of tests show that the software is running stably and system features are functioning correctly on Windows 2000/XP/2003 platform with Office XP/2003 environment. 展开更多
关键词 Question Bank test paper Generation DATABASE VBA
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What to test and how to test: An evaluation of the Academic version of the International English Language Testing System
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作者 孙由之 《海外英语》 2014年第15期103-104,106,共3页
An attempt was made to evaluate what is tested and how it is tested in the IELTS academic test from a thinking-based perspective. The analysis framework is an incorporation of Bloom's taxonomy of educational objec... An attempt was made to evaluate what is tested and how it is tested in the IELTS academic test from a thinking-based perspective. The analysis framework is an incorporation of Bloom's taxonomy of educational objectives and Bachman's classification of language knowledge. It is found that the IELTS test exemplifies an assessment of test-takers' language knowledge and cognitive processes. 展开更多
关键词 test evaluation thinking-based TAXONOMY of educati
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Pulsed Eddy Current Non-destructive Testing and Evaluation:A Review 被引量:31
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作者 Ali Sophian Guiyun Tian Mengbao Fan 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2017年第3期500-514,共15页
Pulsed eddy current (PEC) non-destructive test- ing and evaluation (NDT&E) has been around for some time and it is still attracting extensive attention from researchers around the globe, which can be witnessed th... Pulsed eddy current (PEC) non-destructive test- ing and evaluation (NDT&E) has been around for some time and it is still attracting extensive attention from researchers around the globe, which can be witnessed through the reports reviewed in this paper. Thanks to its richness of spectral components, various applications of this technique have been proposed and reported in the lit- erature covering both structural integrity inspection and material characterization in various industrial sectors. To support its development and for better understanding of the phenomena around the transient induced eddy currents, attempts for its modelling both analytically and numeri- cally have been made by researchers around the world. This review is an attempt to capture the state-of-the-art development and applications of PEC, especially in the last 15 years and it is not intended to be exhaustive. Future challenges and opportunities for PEC NDT&E are also presented. 展开更多
关键词 Non-destructive testing - Pulsed eddy currentsMaterial characterization Structural integrity Non-destructive evaluation
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Analysis of the integrated test and evaluation methods of tidal current energy generating devices in the offshore testing site
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作者 郭文瑞 朱永强 +3 位作者 叶青 李雪临 王鑫 段春明 《Marine Science Bulletin》 CAS 2014年第2期60-71,共12页
Actual sea condition testing and inspection and evaluation method research are carried out for tidal energy devices to provide scientific and effective technical support for the ocean high-tech achievement transformat... Actual sea condition testing and inspection and evaluation method research are carried out for tidal energy devices to provide scientific and effective technical support for the ocean high-tech achievement transformation and marine renewable energy development. By analyzing three core indicators, including the power output characteristics of the tidal current device, the generating capacity, energy conversion efficiency, proposed the test contents and evaluation methods of indicators are proposed in this paper; and based on the research of wind farms, power quality testing and assessment methods of offshore tidal energy device are proposed; given the security access to the test contents of tidal current energy device, tidal current energy device running conditions in the testing ground are comprehensively assessed. 展开更多
关键词 testing ground tidal current energy generating device integrated test evaluation method
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Testing and Evaluation for Web Usability Based on Extended Markov Chain Model 被引量:2
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作者 MAOCheng-ying LUYan-sheng 《Wuhan University Journal of Natural Sciences》 EI CAS 2004年第5期687-693,共7页
As the increasing popularity and complexity of Web applications and the emergence of their new characteristics, the testing and maintenance of large, complex Web applications are becoming more complex and difficult. W... As the increasing popularity and complexity of Web applications and the emergence of their new characteristics, the testing and maintenance of large, complex Web applications are becoming more complex and difficult. Web applications generally contain lots of pages and are used by enormous users. Statistical testing is an effective way of ensuring their quality. Web usage can be accurately described by Markov chain which has been proved to be an ideal model for software statistical testing. The results of unit testing can be utilized in the latter stages, which is an important strategy for bottom-to-top integration testing, and the other improvement of extended Markov chain model (EMM) is to present the error type vector which is treated as a part of page node. this paper also proposes the algorithm for generating test cases of usage paths. Finally, optional usage reliability evaluation methods and an incremental usability regression testing model for testing and evaluation are presented. Key words statistical testing - evaluation for Web usability - extended Markov chain model (EMM) - Web log mining - reliability evaluation CLC number TP311. 5 Foundation item: Supported by the National Defence Research Project (No. 41315. 9. 2) and National Science and Technology Plan (2001BA102A04-02-03)Biography: MAO Cheng-ying (1978-), male, Ph.D. candidate, research direction: software testing. Research direction: advanced database system, software testing, component technology and data mining. 展开更多
关键词 statistical testing evaluation for Web usability extended Markov chain model (EMM) Web log mining reliability evaluation
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Correction to: Recent developments in photoacoustic imaging and sensing for nondestructive testing and evaluation 被引量:2
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作者 Sung-Liang Chen Chao Tian 《Visual Computing for Industry,Biomedicine,and Art》 EI 2021年第1期90-90,共1页
Following publication of the original article[1],the authors identified an error in the article title.The first word ‘Review’ is added mistakenly by the typesetter.
关键词 testing MISTAKE evaluation
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Evaluation of a Rapid Diagnostic Test, Boson Biotech SARS CoV-2 Ag, for the Detection of SARS-CoV-2 in Gabon
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作者 Samira Zoa Assoumou Ulrich Leger Davy Mouangala +6 位作者 Ludovic Mewono Davy-Christ Angoune Ndong Guy Paterne Malonga Mbembo Nely Meungang Alain Moutsinga Elvyre Anita Mbongo Kama Rodrigue Mintsa Nguema 《Advances in Infectious Diseases》 CAS 2024年第2期469-477,共9页
1) Background: Rapid and acurate diagnostic testing for case identification, quarantine, and contact tracing is essential for managing the COVID 19 pandemic. Rapid antigen detection tests are available, however, it is... 1) Background: Rapid and acurate diagnostic testing for case identification, quarantine, and contact tracing is essential for managing the COVID 19 pandemic. Rapid antigen detection tests are available, however, it is important to evaluate their performances before use. We tested a rapid antigen detection of SARS-CoV-2, based on the immunochromatography (Boson Biotech SARS-CoV-2 Ag Test (Xiamen Boson Biotech Co., Ltd., China)) and the results were compared with the real time reverse transcriptase-Polymerase chain reaction (RT-PCR) (Gold standard) results;2) Methods: From November 2021 to December 2021, samples were collected from symptomatic patients and asymptomatic individuals referred for testing in a hospital during the second pandemic wave in Gabon. All these participants attending “CTA Angondjé”, a field hospital set up as part of the management of COVID-19 in Gabon. Two nasopharyngeal swabs were collected in all the patients, one for Ag test and the other for RT-PCR;3) Results: A total of 300 samples were collected from 189 symptomatic and 111 asymptomatic individuals. The sensitivity and specificity of the antigen test were 82.5% [95%CI 73.8 - 89.3] and 97.9 % [95%CI 92.2 - 98.2] respectively, and the diagnostic accuracy was 84.4% (95% CI: 79.8 - 88.3%). The antigen test was more likely to be positive for samples with RT-PCR Ct values ≤ 32, with a sensitivity of 89.8%;4) Conclusions: The Boson Biotech SARS-CoV-2 Ag Test has good sensitivity and can detect SARS-CoV-2 infection, especially among symptomatic individuals with low viral load. This test could be incorporated into efficient testing algorithms as an alternative to PCR to decrease diagnostic delays and curb viral transmission. 展开更多
关键词 SARS-CoV-2 Rapid Diagnostic test evaluation COVID-19 ANTIGEN Performance
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Recent developments in photoacoustic imaging and sensing for nondestructive testing and evaluation 被引量:2
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作者 Sung-Liang Chen Chao Tian 《Visual Computing for Industry,Biomedicine,and Art》 EI 2021年第1期50-62,共13页
Photoacoustic(PA)imaging has been widely used in biomedical research and preclinical studies during the past two decades.It has also been explored for nondestructive testing and evaluation(NDT/E)and for industrial app... Photoacoustic(PA)imaging has been widely used in biomedical research and preclinical studies during the past two decades.It has also been explored for nondestructive testing and evaluation(NDT/E)and for industrial applications.This paper describes the basic principles of PA technology for NDT/E and its applications in recent years.PA technology for NDT/E includes the use of a modulated continuous-wave laser and a pulsed laser for PA wave excitation,PA-generated ultrasonic waves,and all-optical PA wave excitation and detection.PA technology for NDT/E has demonstrated broad applications,including the imaging of railway cracks and defects,the imaging of Li metal batteries,the measurements of the porosity and Young’s modulus,the detection of defects and damage in silicon wafers,and a visualization of underdrawings in paintings. 展开更多
关键词 Photoacoustic imaging Photoacoustic sensing Nondestructive testing Nondestructive evaluation Photoacoustic microscopy
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Multilevel Tests and Measurement Evaluation Methods for the Application of Composite Materials in Spacecraft Structures 被引量:1
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作者 WANG Yuhang GUO Liangshuai +2 位作者 ZHOU Peng ZHANG Tao WANG Fuhui 《上海航天(中英文)》 CSCD 2022年第1期111-121,共11页
With the implementation of new-generation launch vehicles,space stations,lunar and deep space exploration,etc.,the development of spacecraft structures will face new challenges. In order to reduce the spacecraft weigh... With the implementation of new-generation launch vehicles,space stations,lunar and deep space exploration,etc.,the development of spacecraft structures will face new challenges. In order to reduce the spacecraft weight and increase the payload,composite material structures will be widely used. It is difficult to evaluate the strength and life of composite materials due to their complex mechanism and various phenomena in damage and failure.Meanwhile,the structures of composite materials used in spacecrafts will bear complex loads,including the coupling loads of tension,pressure,bending,shear,and torsion. Static loads,thermal loads,and vibration loads may occur at the same time,which asks for verification requirements to ensure the structure safety. Therefore,it is necessary to carry out a systematic multi-level experimental study. In this paper,the building block approach (BBA) is used to investigate the multilevel composite material structures for spacecrafts. The advanced measurement technology is adopted based on digital image correlation (DIC) and piezoelectric and optical fiber sensors to measure the composite material structure deformation. The virtual experiment technology is applied to provide sufficient and reliable data for the evaluation of the composite material structures of spacecrafts. 展开更多
关键词 composite material structure SPACECRAFT multilevel test measurement evaluation
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Construction of an evaluation index system for the innovativeness of nursing papers using the Delphi method 被引量:1
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作者 Shi-Fan Han Rui-Fang Zhu +1 位作者 Jin-Lian Cheng Yan Cao 《Chinese Nursing Research》 CAS 2017年第3期151-154,共4页
Objective: The goal of this study was to construct an evaluation index system for the innovativeness of nursing papers. Methods: A total of 17 nursing experts were consulted for two rounds, and the reliability and w... Objective: The goal of this study was to construct an evaluation index system for the innovativeness of nursing papers. Methods: A total of 17 nursing experts were consulted for two rounds, and the reliability and weight of the constructed evaluation index system for the innovativeness of nursing papers were determined. Results: An evaluation system for the innovativeness of nursing papers was constructed, including 3 primary indexes, 8 secondary indexes, 14 tertiary indexes, and 8 quaternary indexes. The 3 primary indexes with their weights were new argument (0.547), new evidence (0.345), and new conclusion (0.109). Conclusions: The representativeness, the enthusiasm for the study, the degree of authority, the degree of coordination, and the convergence of the experts were high: therefore, an evaluation index system for the innovativeness of nursing papers based on the Delphi method can comprehensively and scientifically evaluate the innovativeness of nursing papers. 展开更多
关键词 Delphi Nursing paper lnnovativeness evaluation Index system
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Evaluation on washback effects of College English Test Band 4 被引量:1
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作者 WANG Wen-jun 《Sino-US English Teaching》 2010年第2期35-40,共6页
The paper is an evaluative research on the possible washback effects of College English Test. By comparing and analyzing the differences between the old and new tests, it points out three major changes and their possi... The paper is an evaluative research on the possible washback effects of College English Test. By comparing and analyzing the differences between the old and new tests, it points out three major changes and their possible washback effects on the process of English language teaching and learning: abandon the part of Grammar & Vocabulary, increase the proportion of listening test and change the test reporting form. 展开更多
关键词 washback effects test evaluation College English test
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The effect of grade entitlement attitudes on English programs in Japanese universities language testing and evaluation: Foreign language skill development 被引量:1
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作者 Kelly Quinn Chikako Matsuura 《Sino-US English Teaching》 2010年第2期12-16,29,共6页
This paper deals with the effect of grade entitlement on English programs in Japanese universities. For years, teachers and administrators have noted that even though Japan is one of the highest spending countries on ... This paper deals with the effect of grade entitlement on English programs in Japanese universities. For years, teachers and administrators have noted that even though Japan is one of the highest spending countries on English education, there has not been a commensurate increase in English ability. Most research to explain this disparity has thus far focused on methodology, class size and teacher qualifications. Recent research dealing with academic entitlement at US universities may offer an alternative explanation for some of the lack of success that Japanese universities have experienced. Ellen Greenberger, one of the author's of Self-entitled college students: Contributions of personality, parenting and motivational factors, which appeared in 2008 in The Journal of Youth and Adolescence claims that in recent years, the number of students appealing their grades and expecting to be rewarded for effort rather than results has increased. Greenberger's paper motivated this study. 200 Japanese students completed a survey that presented a number of grade scenarios. The students were asked, based on test grades and completed assignments, what grade a student should receive in each hypothetical situation. Similarly, full-time and part-time teachers were asked what grade they would give in each situation. This paper explains the different situations, students' and teachers' responses to the scenarios, and then discusses the implications for English education in Japan. 展开更多
关键词 evaluation student feedback testing
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Evaluation of an Oral Test Paper
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作者 曾艾玲 《海外英语》 2012年第8X期108-110,共3页
This paper is to evaluate an oral test paper for the middle school graduates of Jiangsu Province according to its validity and reliability.And then the advice on how to improve the reliability is given.
关键词 ORAL test paper validity RELIABILITY evaluation
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CHINA FOUNDRY Outstanding Paper Award Evaluation Results
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《China Foundry》 SCIE 2017年第6期541-542,共2页
CHINA FOUNDRY,begun in August 2004,sponsored by Shenyang Research Institute of Foundry,the only foundry research institution in China’s foundry industry,is a peer-revewed and SCI-E-indexed scholarly journal.It is now... CHINA FOUNDRY,begun in August 2004,sponsored by Shenyang Research Institute of Foundry,the only foundry research institution in China’s foundry industry,is a peer-revewed and SCI-E-indexed scholarly journal.It is now published jointly by Foundry Journal Agency and Springer in English to a worldwide readership.In order to recognize high quality and highly cited papers,and to enhance the quality and academic level of journal publication,CHINA FOUNDRY journal agency assessed articles published in 2015 and 2016. 展开更多
关键词 ZHANG CNY CHINA FOUNDRY Outstanding paper Award evaluation Results
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Effect of Rating Scales and Test Parts of Body on the Evaluation Results of Fabric-evoked Prickle
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作者 王革辉 RON Postle 张渭源 《Journal of Donghua University(English Edition)》 EI CAS 2006年第3期102-105,共4页
The effect of rating scales and test parts of body on the fabric-evoked prickle evaluation results are studied by carrying out subjective evaluation tests under controlled environment conditions (24 4±1)℃, (6... The effect of rating scales and test parts of body on the fabric-evoked prickle evaluation results are studied by carrying out subjective evaluation tests under controlled environment conditions (24 4±1)℃, (65 =l= 5) %RH. Ten college female students aged about 20 were chosen as the subjects, who have participated a preliminary training on subjective prickle evaluation. The prickle of a range of 9 light-weight worsted woven wool and wool blend fabrics and a cotton fabric were tested by using a 1 - 5 rating scale and using a 0 - 10 rating scale respectively at different test parts of body respectively such as forearm, upper arm ball and neck back. The test results were statistically analyzed. It is found that there is a significant correlation coefficient between the evaluation results of using the 1 - 5 rating scale and of using the 0- 10 rating scale. It is also found that there are highly significant correlation coefficients between the evaluation results of using the forearm prickle test and the neck back prickle test, between the evaluation results of using the neck back prickle test and the upper arm ball prickle test, and between the evaluation results of using the forearm prickle test and the upper arm ball prickle test. It is suggested that the forearm prickle test is preferable in evaluating fabric-evoked prickle for its convenience and sensitivity. 展开更多
关键词 subjective evaluation fabric-evoked prickle rating scale forearm test.
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Numerical test and evaluating method of impact trend of rock-coal system
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作者 蒋金泉 程家国 +1 位作者 曲华 董建军 《Journal of Coal Science & Engineering(China)》 2008年第1期12-18,共7页
The impact trend of reck-coal system was studied by the method of accumulating and releasing of deformation energy and interaction of rock-coal system. The system model of roof-coal-floor was established. Based on the... The impact trend of reck-coal system was studied by the method of accumulating and releasing of deformation energy and interaction of rock-coal system. The system model of roof-coal-floor was established. Based on the RFPA software, rock fracture process analysis system, the numerical test of deformation, fracture and energy transmission of nonlinear and nonhomogeneous rock-coal system, and the numerical test and evaluating method of impact trend of reck-coal system were achieved. When the same coal seam was in different roof and floor conditions, the fracture process of reck-coal system can be classified as gradual, sudden and delayed fracture three kinds, and their impact trend can be classified as void, intense and medium correspondingly. The rock-coal system's impact trend is evaluated by the system impact index p and burst expanding forms. The criteria μ are μ〈1.0, 1.0≤μ〈l .5 and μ≥1.5 when the impact trend is void, intense or medium, which are tested and verified by the No.2 and No.4 coal seams in Sun- cun mine. 展开更多
关键词 impact trend rock-coal system numerical test impact energy index evaluating method
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Design and Evaluation of a Differential Accelerometer for Drop-Tower Equivalence Principle Test with Rotating Masses
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作者 Feng-Tian Han Tian-Yi Liu +1 位作者 Xiao-Xia He Qiu-Ping Wu 《Chinese Physics Letters》 SCIE CAS CSCD 2017年第10期13-17,共5页
A differential accelerometer comprising of two rotating masses made of the same material is proposed for drop tower-based free-fall testing of the spin-spin force between the rotating mass and the Earth. The measureme... A differential accelerometer comprising of two rotating masses made of the same material is proposed for drop tower-based free-fall testing of the spin-spin force between the rotating mass and the Earth. The measurement is performed by placing the two concentric masses of very different momenta in a vacuum drop capsule which is falling freely in the Earth's gravitational field. A nonzero output of the differential aeeelerometer is an indication of possible violation of new equivalence principle (NEP). We present the conceptual design of a modified free-fall NEP experiment which can be performed at the Belting drop tower. Design and evaluation of the differential accelerometer with a hybrid electrostatic/magnetic suspension system are presented to accommodate for operation on ground and drop-tower tests. Details specific to the measurement uncertainty are discussed to yield an NEP test accuracy of 7.2×10^-9. 展开更多
关键词 TM Design and evaluation of a Differential Accelerometer for Drop-Tower Equivalence Principle test with Rotating Masses NEP
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Evaluation of HCV core antigen ELISA test system in Korean blood donors
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《中国输血杂志》 CAS CSCD 2001年第S1期404-,共1页
关键词 HCV ELISA CORE evaluation of HCV core antigen ELISA test system in Korean blood donors
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