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A dual-RPA based lateral flow strip for sensitive,on-site detection of CP4-EPSPS and Cry1Ab/Ac genes in genetically modified crops 被引量:1
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作者 Jinbin Wang Yu Wang +7 位作者 Xiuwen Hu Yifan Chen Wei Jiang Xiaofeng Liu Juan Liu Lemei Zhu Haijuan Zeng Hua Liu 《Food Science and Human Wellness》 SCIE CSCD 2024年第1期183-190,共8页
Traditional transgenic detection methods require high test conditions and struggle to be both sensitive and efficient.In this study,a one-tube dual recombinase polymerase amplification(RPA)reaction system for CP4-EPSP... Traditional transgenic detection methods require high test conditions and struggle to be both sensitive and efficient.In this study,a one-tube dual recombinase polymerase amplification(RPA)reaction system for CP4-EPSPS and Cry1Ab/Ac was proposed and combined with a lateral flow immunochromatographic assay,named“Dual-RPA-LFD”,to visualize the dual detection of genetically modified(GM)crops.In which,the herbicide tolerance gene CP4-EPSPS and the insect resistance gene Cry1Ab/Ac were selected as targets taking into account the current status of the most widespread application of insect resistance and herbicide tolerance traits and their stacked traits.Gradient diluted plasmids,transgenic standards,and actual samples were used as templates to conduct sensitivity,specificity,and practicality assays,respectively.The constructed method achieved the visual detection of plasmid at levels as low as 100 copies,demonstrating its high sensitivity.In addition,good applicability to transgenic samples was observed,with no cross-interference between two test lines and no influence from other genes.In conclusion,this strategy achieved the expected purpose of simultaneous detection of the two popular targets in GM crops within 20 min at 37°C in a rapid,equipmentfree field manner,providing a new alternative for rapid screening for transgenic assays in the field. 展开更多
关键词 Genetically modifi ed crops on-site detection Lateral fl ow test strips Dual recombinase polymerase amplification (RPA)
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Acceptance Sampling Plans with Truncated Life Tests for the Length-Biased Weighted Lomax Distribution 被引量:1
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作者 Amer Ibrahim Al-Omari Ibrahim M.Almanjahie Olena Kravchuk 《Computers, Materials & Continua》 SCIE EI 2021年第4期285-301,共17页
In this paper,we considered the Length-biased weighted Lomax distribution and constructed new acceptance sampling plans(ASPs)where the life test is assumed to be truncated at a pre-assigned time.For the new suggested ... In this paper,we considered the Length-biased weighted Lomax distribution and constructed new acceptance sampling plans(ASPs)where the life test is assumed to be truncated at a pre-assigned time.For the new suggested ASPs,the tables of the minimum samples sizes needed to assert a specific mean life of the test units are obtained.In addition,the values of the corresponding operating characteristic function and the associated producer’s risks are calculated.Analyses of two real data sets are presented to investigate the applicability of the proposed acceptance sampling plans;one data set contains the first failure of 20 small electric carts,and the other data set contains the failure times of the air conditioning system of an airplane.Comparisons are made between the proposed acceptance sampling plans and some existing acceptance sampling plans considered in this study based on the minimum sample sizes.It is observed that the samples sizes based on the proposed acceptance sampling plans are less than their competitors considered in this study.The suggested acceptance sampling plans are recommended for practitioners in the field. 展开更多
关键词 acceptance sampling plan producer’s risk truncated life tests operating characteristic function length-biased weighted lomax distribution consumer’s risk
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New Explorations of Laboratory and On-site Testing of Broadband Seismographs in China
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作者 XIE Jianbo YANG Dake +6 位作者 LI Xiaojun YUAN Songyong TONG Wanglian MA Jiemei XU Weiwei DING Lisha YE Shishan 《Earthquake Research in China》 CSCD 2019年第1期9-23,共15页
According to different testing purposes, methods and available environmental conditions, the seismograph testing can be divided into laboratory and on-site testing, respectively. The testing of the seismograph's k... According to different testing purposes, methods and available environmental conditions, the seismograph testing can be divided into laboratory and on-site testing, respectively. The testing of the seismograph's key parameters and other concerning technical specifications are well described in guide documents(China Earthquake Administration, 2017). This includes seismometer sensitivity, linearity and clip levels based on the shake table test, as well as the seismometer natural period, damping constant based on electrical calibration(Wang Guangfu,1986; Ple?inger A.,1993) and instrumental self-noise collocation estimation(Holcomb L.G., 1989; Sleeman R. et al., 2006). However, with the development of seismic observation technology, many new requirements for the performance evaluation of seismographs have been put forward, and new testing items and methods have emerged. 展开更多
关键词 BROADBAND seismographs LABORATORY testING on-site testING
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Traceability in Acceptance Testing
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作者 Jean-Pierre Corriveau Wei Shi 《Journal of Software Engineering and Applications》 2013年第10期36-46,共11页
Regardless of which (model-centric or code-centric) development process is adopted, industrial software production ultimately and necessarily requires the delivery of an executable implementation. It is generally acce... Regardless of which (model-centric or code-centric) development process is adopted, industrial software production ultimately and necessarily requires the delivery of an executable implementation. It is generally accepted that the quality of such an implementation is of utmost importance. Yet current verification techniques, including software testing, remain problematic. In this paper, we focus on acceptance testing, that is, on the validation of the actual behavior of the implementation under test against the requirements of stakeholder(s). This task must be as objective and automated as possible. Our first goal is to review existing code-based and model-based tools for testing in light of what such an objective and automated approach to acceptance testing entails. Our contention is that the difficulties we identify originate mainly in a lack of traceability between a testable model of the requirements of the stakeholder(s) and the test cases used to validate these requirements. We then investigate whether such traceability is addressed in other relevant specification-based approaches. 展开更多
关键词 VALIDATION acceptance testING MODEL-BASED testING TRACEABILITY SCENARIO Models
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Problems of Environmental Acceptance Tests on Power Transmission and Transformation Projects
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作者 Zhang Lei Environmental Engineering Assessment Center, Ministry of Environmental Protection Zhang Jianping 《Electricity》 2011年第4期58-61,共4页
Based on the experience of environmental acceptance tests for power transmission projects, the problems found in acceptance tests and the system shortcomings of acceptance test itself are analyzed. Recommendations are... Based on the experience of environmental acceptance tests for power transmission projects, the problems found in acceptance tests and the system shortcomings of acceptance test itself are analyzed. Recommendations are provided to improve the future work. 展开更多
关键词 power transmission project environmental acceptance test environmental assessment
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Northeast China's largest transmission and substation project passed the acceptance test
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《Electricity》 2001年第4期51-51,共1页
关键词 Northeast China’s largest transmission and substation project passed the acceptance test LINE
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An Experience of On-site PD Testing for Condition Monitoring of an 11 kV PILC Cable Insulation System
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作者 Xiaosheng Peng Chengke Zhou Xiaodi Song 《Journal of Energy and Power Engineering》 2012年第1期140-145,共6页
A cable circuit of a substation in the United Kingdom showed high level of PD activities during a survey using hand hold PD testing equipment. The authors were invited to carry out on-site PD testing experiment to fur... A cable circuit of a substation in the United Kingdom showed high level of PD activities during a survey using hand hold PD testing equipment. The authors were invited to carry out on-site PD testing experiment to further diagnose and locate the potential problem of the cable system. This paper presents the experience of the present authors carrying out the cable test. Following a brief introduction to the experiment equipments and physical connections, the paper analyses the data collected from the testing, including PD pulse shape analysis, frequency spectrum analysis and phase resolved PD pattern analysis. Associated with PD propagation direction identification, PD source diagnosis and localisation was made. Four different types of sensors, which were adapted during the testing, are shown to have different frequency bandwidths and performed differently. Aider comparing the parameters of the sensor and the PD signals detected by individual sensor, optimal PD monitoring bandwidth for cable system is suggested. 展开更多
关键词 PD identification on-site testing PILC cable switchgear box insulation defect PD propagation direction sensor.
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120-ton Thrust Liquid-Oxygen/Kerosene Engine Passed Acceptance Test
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《Aerospace China》 2012年第2期24-24,共1页
On May 28, the 120-ton thrust liquid-oxygen/kerosene engine developed by the Academy of Aerospace Liquid Propulsion Technology (AALPT) passed the acceptance test organized by China National Space Administration (CNSA)... On May 28, the 120-ton thrust liquid-oxygen/kerosene engine developed by the Academy of Aerospace Liquid Propulsion Technology (AALPT) passed the acceptance test organized by China National Space Administration (CNSA). The 120-ton thrust liquid-oxygen/kerosene engine is a non-pollution, non-toxic, high performance and reliable basic pro- 展开更多
关键词 ENGINE ton Thrust Liquid-Oxygen/Kerosene Engine Passed acceptance test high
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An Acceptance Model of Using Mobile-Government Services(AMGS) 被引量:2
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作者 Ahmad Althunibat Mohammad Abdallah +2 位作者 Mohammed Amin Almaiah Nour Alabwaini Thamer Ahmad Alrawashdeh 《Computer Modeling in Engineering & Sciences》 SCIE EI 2022年第5期865-880,共16页
In recent years,the telecommunications sector is no longer limited to traditional communications,but has become the backbone for the use of data,content and digital applications by individuals,governments and companie... In recent years,the telecommunications sector is no longer limited to traditional communications,but has become the backbone for the use of data,content and digital applications by individuals,governments and companies to ensure the continuation of economic and social activity in light of social distancing and total closure inmost countries in the world.Therefore,electronic government(e-Government)andmobile government(m-Government)are the results of technological evolution and innovation.Hence,it is important to investigate the factors that influence the intention to use m-Government services among Jordan’s society.This paper proposed a new m-Government acceptance model in Jordan(AMGS);this model combines the Information System(IS)Success Factor Model and Hofstede Cultural Dimensions Theory.The study was conducted by surveying different groups of the Jordanian community.Astructured questionnaire was used to collect data from203 respondents.Multiple regression analysis has been conducted to analyze the data.The results indicate that the significant predictors of citizen intention to use m-Government services in Jordan are Information Quality,Service Quality,Uncertainty Avoidance,and Indulgence vs.restraint.While,the results also suggest that Power Distance is not a significant predictor of citizen intention to use m-Government services. 展开更多
关键词 acceptance test E-GOVERNMENT m-Government acceptance model IS success factor model Hofstede cultural dimensions theory
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Assessing the Acceptability and Willingness to Use HIV Self-Testing among Student Nurses in a Private Nursing College, Gauteng Province, South Africa
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作者 Sphiwe Madiba Molly Segobola Mathildah Mokgatle 《World Journal of AIDS》 2015年第3期208-216,共9页
Globally, there is increasing evidence that HIV self-testing (HIVST) is commonly practiced among health care workers (HCWs). Although HIVST kits are available in South Africa, their distribution and use remain unregul... Globally, there is increasing evidence that HIV self-testing (HIVST) is commonly practiced among health care workers (HCWs). Although HIVST kits are available in South Africa, their distribution and use remain unregulated and its acceptability, undocumented. The aim of the study was to explore the acceptability of HIV self-testing among student nurses, examine their willingness to use self-testing, and evaluate their views on the implementation of a regulated HIV self-testing programme. This was a qualitative explorative study, and six focus group discussions were conducted with 67 student nurses recruited from a private nursing college, in Pretoria, South Africa. Thematic analysis and NVivo10 qualitative software were used for data analysis. The nurses perceived HIVST as an acceptable option for HIV testing and most were willing to self-test. Self-testing will provide confidential and accessible HIV testing services, reduce the stigma associated with the condition, and increase partner testing and disclosure. HIVST is more likely to be practised if self-testing kits are easily accessible and affordable, and there are strategies to educate people before the adoption of HIVST. The lack of pre- and post-test counselling, the risk of inaccurate test results, and lack of strategies for the confirmation of self-testing results were the main arguments against HIVST. The high acceptance of HIVST among nurses suggests that HIVST is a feasible option to increase the uptake of HIV-testing among HCWs. However, pre- and post-test counselling should be considered important components in the implementation of self-testing services. Educational and awareness campaigns should precede the roll-out of the self-testing programs. 展开更多
关键词 HIV SELF-testING Nurses acceptABILITY South AFRICA Health Care Workers
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开关柜合格性检验的力矩奇异性特征分析方法
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作者 张铁 杨明达 邹焱飚 《机械设计与制造》 北大核心 2024年第4期361-367,共7页
面向开关柜的合格性检验,提出一种基于力矩信号奇异性分析的检验算法。根据开关柜的合格性与力矩信号的奇异性特征的相关性,提出将力矩信号的12个统计学特征通过Fisher判别法压缩至5个,并将由该特征组成的样本集输入至SVM分类器中训练... 面向开关柜的合格性检验,提出一种基于力矩信号奇异性分析的检验算法。根据开关柜的合格性与力矩信号的奇异性特征的相关性,提出将力矩信号的12个统计学特征通过Fisher判别法压缩至5个,并将由该特征组成的样本集输入至SVM分类器中训练出能判别开关柜合格性的SVM模型。最后对所提算法进行了实验验证,结果表明所提算法对开关柜的合格性检验的识别率达100%,延迟在30ms以内,所识别点均落在设定区域内。阻尼干扰下,与小波变换理论算法相比,在兼顾快速响应的同时鲁棒性更好,且不需要大量的训练样本和训练时间。 展开更多
关键词 机器人 合格性检验 力矩 奇异性特征分析
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上海市域铁路新建项目工程验收办法及安全评估方案研究
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作者 刘智平 刘洋 《城市轨道交通研究》 北大核心 2024年第4期61-66,共6页
[目的]上海市域铁路已有多个项目开工建设,但目前尚无明确的市域铁路新建项目工程验收办法及安全评估管理办法。为了对市域铁路新建项目工程验收、安全评估等管理办法的制定提供合理化建议,亟需开展市域铁路项目工程验收办法及安全评估... [目的]上海市域铁路已有多个项目开工建设,但目前尚无明确的市域铁路新建项目工程验收办法及安全评估管理办法。为了对市域铁路新建项目工程验收、安全评估等管理办法的制定提供合理化建议,亟需开展市域铁路项目工程验收办法及安全评估方案的研究。[方法]从主要技术标准、建设及运营特点两方面,分析了市域铁路同地铁、国家铁路的差异。阐述了地铁、国家铁路建设项目工程验收及安全评估程序,讨论了二者在项目验收组织、验收程序及验收内容等方面的差异。在此基础上,针对上海市域铁路新建项目工程验收及安全评估的具体工作流程,提出了2个备选方案(方案一、方案二),并对2个方案进行了比选,提出适用于上海市域铁路新建项目验收及安全评估工作流程的建议方案。[结果及结论]上海市域铁路新建项目的工程验收及安全评估建议采用方案二,即上海市域铁路项目工程验收的程序及组织方式基本沿用地铁模式,并参照国家铁路项目的标准设置联调联试流程。 展开更多
关键词 市域铁路 新建项目 工程验收 安全评估 联调联试
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全厂及汽轮机岛性能试验标准比对和实践研究
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作者 李麟 张朋飞 +1 位作者 罗碧星 陆梁 《热力透平》 2024年第2期113-117,共5页
性能验收试验是燃煤发电机组建设工程验收的关键一环,其准确有效的前期规划和实践管理对于燃煤电站建设工程的合同制定和项目移交起着至关重要的作用。结合海外燃煤发电工程项目和国内燃煤发电工程项目性能验收试验实践现状,对比分析了... 性能验收试验是燃煤发电机组建设工程验收的关键一环,其准确有效的前期规划和实践管理对于燃煤电站建设工程的合同制定和项目移交起着至关重要的作用。结合海外燃煤发电工程项目和国内燃煤发电工程项目性能验收试验实践现状,对比分析了国标和相应ASME标准关于全厂及汽轮机性能验收试验的差异,结合二者在工程实践中的应用情况,提出了前期技术协议规划和现场实践中的注意要点。研究成果可为海外燃煤发电工程项目的前期规划和项目管理提供指导,同时可为性能试验的标准化研究提供参考。 展开更多
关键词 燃煤电站 性能验收试验 国标体系 ASME体系
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液化天然气(LNG)接收站高倍数泡沫灭火系统安装测试及试运行的控制要点
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作者 周怀发 《石油工业技术监督》 2024年第1期44-46,52,共4页
针对LNG接收站集液池所配高倍数泡沫灭火系统在安装测试及试运行中存在的问题,以某接收站高倍数泡沫灭火系统为例,通过总结高倍数泡沫灭火系统的结构特点、工作原理和应用现状,对系统测试、试运行期间的水力试验、气密性测试、发泡效果... 针对LNG接收站集液池所配高倍数泡沫灭火系统在安装测试及试运行中存在的问题,以某接收站高倍数泡沫灭火系统为例,通过总结高倍数泡沫灭火系统的结构特点、工作原理和应用现状,对系统测试、试运行期间的水力试验、气密性测试、发泡效果试验和联锁测试应注意的问题进行了分析,并对高倍数泡沫灭火系统试运行过程中可能出现的泄漏、发泡效果差、通讯故障等问题提出了解决办法,为今后LNG高倍数泡沫灭火系统的系统选型和测试验收提供了参考。 展开更多
关键词 LNG 高倍数 泡沫 灭火 测试验收
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普通话噪声接受度追踪测试材料的开发与等价性评估 被引量:1
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作者 郑雨晴 龚嘉敏 +7 位作者 管鹏飞 冯佳玲 肖永涛 樊婷 代阿强 周柔嘉 李华伟 王云峰 《听力学及言语疾病杂志》 CAS CSCD 北大核心 2024年第4期302-307,共6页
目的开发普通话噪声接受度追踪(tracking of noise tolerance,TNT)测试材料并进行等价性评估。方法开发6组易于普通大众理解的言语材料(主题分别为日常生活、娱乐、家庭、节日、户外和学校);选取21例听力正常人分别进行6组测试材料的4分... 目的开发普通话噪声接受度追踪(tracking of noise tolerance,TNT)测试材料并进行等价性评估。方法开发6组易于普通大众理解的言语材料(主题分别为日常生活、娱乐、家庭、节日、户外和学校);选取21例听力正常人分别进行6组测试材料的4分钟TNT测试,分别计算获得31~240 s、31~120 s、151~240 s三个时间窗的可容忍噪声水平(tolerable noise level,TNL)和TNT分数。结果听力正常个体间TNL值存在差异(F=43.611,P<0.05)。6组测试材料的标准化(z-scored)分数在三个时间窗内均有统计学差异(P<0.05),事后比较发现,所有的显著性差异结果都涉及家庭和/或日常生活主题。结论本研究开发的娱乐、节日、户外和学校的主题测试材料可作为普通话TNT测试的正式测试材料,可应用于实验研究和临床测试。 展开更多
关键词 噪声接受度追踪测试 可接受噪声级 言语识别测试 等价性
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临时造口患者造口接受度现状及其与自我管理行为的关系研究
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作者 王汐嬅 绳宇 +6 位作者 李敏 程悦 郭淑丽 肖毅 侯文红 张冠南 牛备战 《护士进修杂志》 2024年第8期785-789,794,共6页
目的了解临时造口患者的造口接受度现状,分析其影响因素及其与自我管理行为的关系。方法采用便利抽样法,选取2022年3-11月在北京协和医院普外科行临时造口患者126例,采用一般资料调查表、造口自我管理行为问卷、中文版造口接受度问卷进... 目的了解临时造口患者的造口接受度现状,分析其影响因素及其与自我管理行为的关系。方法采用便利抽样法,选取2022年3-11月在北京协和医院普外科行临时造口患者126例,采用一般资料调查表、造口自我管理行为问卷、中文版造口接受度问卷进行问卷调查。结果临时造口患者中文版造口接受度问卷总分为(33.52±2.92)分,条目均分为(2.79±0.73)分,处于中等水平。单因素分析结果显示:不同年龄、文化程度、保留造口时间、主要照顾者及有无合并症对患者造口接受度有影响(P<0.05);Pearson相关性分析结果显示:造口接受度总分与自我管理行为总分及其5个维度均呈正相关(r=0.589、0.617、0.178、0.235、0.416、0.306,P<0.05);多元线性回归分析显示:文化程度、有无合并症及自我管理行为中造口护理维度是造口接受度的影响因素(P<0.01)。结论临时造口患者回归社会后的心理状态是医护人员亟待关注的问题,其造口接受度处于中等水平,可根据影响因素构建有效干预措施提高患者造口接受度,促进自我管理行为,帮助其顺利适应造口生活。 展开更多
关键词 临时造口 接受度 自我管理行为 影响因素 相关性检验 护理
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普通话噪声接受度追踪测试材料的复测信度分析
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作者 关亚琼 付佳蕾 +6 位作者 代阿强 肖永涛 樊婷 管鹏飞 龚嘉敏 周柔嘉 王云峰 《听力学及言语疾病杂志》 CAS CSCD 北大核心 2024年第5期398-402,共5页
目的对普通话噪声接受度追踪(tracking of noise tolerance,TNT)测试材料进行复测信度评估,并比较测试结果的平均可容忍噪声水平(average tolerable noise level,aTNL)与程序估算的TNL值(estimated tolerable noise level,eTNL)是否存... 目的对普通话噪声接受度追踪(tracking of noise tolerance,TNT)测试材料进行复测信度评估,并比较测试结果的平均可容忍噪声水平(average tolerable noise level,aTNL)与程序估算的TNL值(estimated tolerable noise level,eTNL)是否存在差异。方法对25例听力言语正常的成年受试者在测试当天先后进行两次普通话版TNT测试[分别为测试一(C1),测试二(C2)],13例于1周后进行复测[测试三(C3),言语材料主题同C2],三次测试的刺激声条件均为言语声0°,连续语谱噪声180°。通过比较C1与C2、C2与C3的TNT分数和aTNL值的相关性来分别评估普通话版TNT测试材料期内、期间测试的复测信度。结果25例受试者C1、C2的aTNL值分别为83.42±3.09、83.50±3.18 dB SPL,eTNL值分别为84.08±3.53、83.95±3.85 dB SPL;13例受试者C3的aTNL值和eTNL值分别为83.16±2.13、83.18±2.64 dB SPL。期内比较(C1与C2)、期间比较(C2与C3)的TNT分数差值的95%CI分别为2.36、2.75 dB,Pearson相关性分析显示期内(r=0.837,P<0.001)、期间(r=0.867,P<0.001)的复测信度良好。除C1的aTNL与eTNL存在统计学差异(P<0.05)之外,其余TNT测试的aTNL与eTNL均无统计学差异(均P>0.05),且90%以上的受试者可在1分钟内获得eTNL。结论普通话版TNT测试的复测信度良好,具有高可靠性、高效性。 展开更多
关键词 噪声接受度追踪测试 可接受噪声水平 复测信度
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Research advances in enhanced coal seam gas extraction by controllable shock wave fracturing
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作者 Chaojun Fan Hao Sun +6 位作者 Sheng Li Lei Yang Bin Xiao Zhenhua Yang Mingkun Luo Xiaofeng Jiang Lijun Zhou 《International Journal of Coal Science & Technology》 EI CAS CSCD 2024年第3期1-31,共31页
With the continuous increase of mining in depth,the gas extraction faces the challenges of low permeability,great ground stress,high temperature and large gas pressure in coal seam.The controllable shock wave(CSW),as ... With the continuous increase of mining in depth,the gas extraction faces the challenges of low permeability,great ground stress,high temperature and large gas pressure in coal seam.The controllable shock wave(CSW),as a new method for enhancing permeability of coal seam to improve gas extraction,features in the advantages of high efficiency,eco-friendly,and low cost.In order to better utilize the CSW into gas extraction in coal mine,the mechanism and feasibility of CSW enhanced extraction need to be studied.In this paper,the basic principles,the experimental tests,the mathematical models,and the on-site tests of CSW fracturing coal seams are reviewed,thereby its future research directions are provided.Based on the different media between electrodes,the CSW can be divided into three categories:hydraulic effect,wire explosion and excitation of energetic materials by detonating wire.During the process of propagation and attenuation of the high-energy shock wave in coal,the shock wave and bubble pulsation work together to produce an enhanced permeability effect on the coal seam.The stronger the strength of the CSW is,the more cracks created in the coal is,and the greater the length,width and area of the cracks being.The repeated shock on the coal seam is conducive to the formation of complex network fracture system as well as the reduction of coal seam strength,but excessive shock frequency will also damage the coal structure,resulting in the limited effect of the enhanced gas extraction.Under the influence of ground stress,the crack propagation in coal seam will be restrained.The difference of horizontal principal stress has a significant impact on the shape,propagation direction and connectivity of the CSW induced cracks.The permeability enhancement effect of CSW is affected by the breakage degree of coal seam.The shock wave is absorbed by the broken coal,which may hinder the propagation of CSW,resulting in a poor effect of permeability enhancement.When arranging two adjacent boreholes for CSW permeability enhancement test,the spacing of boreholes should not be too close,which may lead to negative pressure mutual pulling in the early stage of drainage.At present,the accurate method for effectively predicting the CSW permeability enhanced range should be further investigated. 展开更多
关键词 Controllable shock wave Permeability enhancement Gas extraction Basic principle Experimental test Mathematical models on-site test
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药品抽检收检环节常见问题分析
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作者 李杏芳 胡碧波 +2 位作者 林瑶琪 张昕 何宇峰 《广东化工》 CAS 2024年第15期85-86,103,共3页
目的:汇总药品抽检中收检环节发现的问题,提出改进方法和建议,进一步规范药品收检工作,从而提高收检工作效率。方法:介绍药品收检工作流程,以2019~2023年国家药品收检工作实践为基础,汇总分析样品接收、样品核对、样品受理、样品购买等... 目的:汇总药品抽检中收检环节发现的问题,提出改进方法和建议,进一步规范药品收检工作,从而提高收检工作效率。方法:介绍药品收检工作流程,以2019~2023年国家药品收检工作实践为基础,汇总分析样品接收、样品核对、样品受理、样品购买等多个节点容易出现的问题,提出注意事项。结果与结论:提高抽样队伍和收检人员的知识技能和专业水平,规范收检工作流程,端正工作态度,明确个人职责分工,全面提升抽检工作质量。 展开更多
关键词 药品抽检 收检环节 样品接收 样品核对 样品受理 样品购买
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基于贝叶斯方法的混凝土强度接收准则研究 被引量:1
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作者 蒋利学 郑士举 王卓琳 《结构工程师》 2024年第5期102-113,共12页
以一次计量抽样检验理论为依据,综合平衡生产方风险和使用方风险,并适当考虑保护生产方利益,提出无论对于标准差已知统计方法还是标准差未知统计方法,混凝土强度平均值的评定系数k均应对应于90%的等效保证率(0.9分位值);并以贝叶斯理论... 以一次计量抽样检验理论为依据,综合平衡生产方风险和使用方风险,并适当考虑保护生产方利益,提出无论对于标准差已知统计方法还是标准差未知统计方法,混凝土强度平均值的评定系数k均应对应于90%的等效保证率(0.9分位值);并以贝叶斯理论为依据确定了标准差未知统计方法的抽样方案。样本容量很小时,以平均质量标准差为依据建立了非统计方法的接收准则,并根据一次计数抽样检验理论提出最小值接收准则,并作为平均值接收准则的补充。采用贝叶斯方法,将前一检验周期内的样本和本次抽样样本合并,通过扩大样本容量,提高了标准差已知统计方法接收准则的检验功效;同时采用贝叶斯方法,综合考虑平均质量标准差和实测样本标准差,提高了非统计方法接收准则的检验功效。本文建议的接收准则具有更明确的统计学依据,通过采用统一的等效保证率使各种方法保持了较接近的检验功效,并用贝叶斯方法将各种方法统一于标准差未知统计方法。实例分析表明,本文建议的接收准则总体上略比GB/T 50107—2010严格,但变动幅度在可接受范围;采用合理的先验标准差后,本文建议的贝叶斯改进方法可以得到科学合理的评定结果。 展开更多
关键词 贝叶斯方法 混凝土强度 接收准则 检验功效 标准差
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