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Research on Automatic Test System of Engine Blade Natural Frequency
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作者 LU Yonghua LIU Jingjing +2 位作者 YANG Haibo HUANG Chuan MA Zhicheng 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI CSCD 2024年第4期476-487,共12页
Blades are one of the important components on aircraft engines.If they break due to vibration failure,the normal operation of the entire engine will be offected.Therefore,it is necessary to measure their natural frequ... Blades are one of the important components on aircraft engines.If they break due to vibration failure,the normal operation of the entire engine will be offected.Therefore,it is necessary to measure their natural frequency before installing them on the engine to avoid resonance.At present,most blade vibration testing systems require manual operation by operators,which has high requirements for operators and the testing process is also very cumbersome.Therefore,the testing efficiency is low and cannot meet the needs of efficient testing.To solve the current problems of low testing efficiency and high operational requirements,a high-precision and high-efficiency automatic test system is designed.The testing accuracy of this system can reach ±1%,and the testing efficiency is improved by 37% compared to manual testing.Firstly,the influence of compression force and vibration exciter position on natural frequency test is analyzed by amplitude-frequency curve,so as to calibrate servo cylinder and fourdimensional motion platform.Secondly,the sine wave signal is used as the excitation to sweep the blade linearly,and the natural frequency is determined by the amplitude peak in the frequency domain.Finally,the accuracy experiment and efficiency experiment are carried out on the developed test system,whose results verify its high efficiency and high precision. 展开更多
关键词 BLADE vibration failure natural frequency automatic test system
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Automatic Control of Automobile Transmission Performance Test Stand
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作者 阎清东 项昌乐 冯永存 《Journal of Beijing Institute of Technology》 EI CAS 1998年第2期178-183,共6页
To realize automatic control of automobile transmission performance test stand Methods The automatic control technique of the lubricant temperature,the program- controll- edautomaticshifting of the transmission,the c... To realize automatic control of automobile transmission performance test stand Methods The automatic control technique of the lubricant temperature,the program- controll- edautomaticshifting of the transmission,the continuous adjusting of revolution speed and load, data-acquisition and data real-time processing were adopted.Results The lubricant temperature was controlled at the set temperature ±2℃.The automatic shifting of the trans- mission is simple,reliable and accurate.The automatic adjusting of load and rotation speed is rapidandaccurate,the torque divergence is ±1N·m,the rotation speed divergence is ±5r/min Conclusion The four kinds of techniques are applied into the automobile transmission perfor- mance test stand successfully. mancetest stand successfully. 展开更多
关键词 automobile transmission performance test computer-aided test automatic control
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城轨全自动运行线路中心ATS系统智能提升方案研究
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作者 邓翔飞 王飞 《铁道通信信号》 2024年第6期15-20,共6页
城市轨道交通全自动运行线路将列车司机的职能交由列车自动控制系统和控制中心相关系统共同完成,而运营控制模式也由传统的司机、控制中心调度员、车站值班员共同参与控制,转变为控制中心调度员直接面向列车运行进行控制。通过分析运营... 城市轨道交通全自动运行线路将列车司机的职能交由列车自动控制系统和控制中心相关系统共同完成,而运营控制模式也由传统的司机、控制中心调度员、车站值班员共同参与控制,转变为控制中心调度员直接面向列车运行进行控制。通过分析运营调度需求及既有运营调度痛点问题,针对新建线路和既有改造线路,分别提出控制中心ATS系统智能提升架构;从供电分区行车数量卡控、行车关键信息融合、全自动编图及行车评估、运维联动、故障及应急指挥等方面,提出具体实施方案,旨在提高全自动运行线路运营效率和故障处理能力。 展开更多
关键词 全自动运行 调度需求 列车自动监控系统 智能提升 运营效率
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城轨全自动运行线路ATS自动洗车功能设计与实现
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作者 高明生 刘灵 +1 位作者 王胜 周公建 《铁道通信信号》 2024年第6期69-74,共6页
自动洗车是城市轨道交通全自动运行线路的一项必备功能。为提高全自动运行项目自动洗车设计效率,减少软件开发成本,提出一种基于序列化动作的自动洗车设计方案。通过分析不同项目自动洗车需求,识别项目之间的共性和区别;设计一套ATS系... 自动洗车是城市轨道交通全自动运行线路的一项必备功能。为提高全自动运行项目自动洗车设计效率,减少软件开发成本,提出一种基于序列化动作的自动洗车设计方案。通过分析不同项目自动洗车需求,识别项目之间的共性和区别;设计一套ATS系统洗车流程数据配置模板,通过修改数据配置即可实现新项目的洗车功能需求;软件采用状态设计模式开发实现,仅需进行一次开发,即可根据数据配置和设备状态自动执行洗车流程。该方案在成都、上海、深圳、郑州等多条全自动运行线路的成功实践,可为类似的全自动功能设计提供思路。 展开更多
关键词 全自动运行 列车自动监控系统 自动洗车功能 状态设计模式 列车工况 列车进路 洗车机
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Comparative study of model tests on automatically formed roadway and gob-side entry driving in deep coal mines 被引量:19
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作者 Qi Wang Manchao He +4 位作者 Shucai Li Zhenhua Jiang Yue Wang Qian Qin Bei Jiang 《International Journal of Mining Science and Technology》 SCIE EI CAS CSCD 2021年第4期591-601,共11页
Automatically formed roadway(AFR)by roof cutting with bolt grouting(RCBG)is a new deep coal mining technology.By using this technology,the broken roadway roof is strengthened,and roof cutting is applied to cut off str... Automatically formed roadway(AFR)by roof cutting with bolt grouting(RCBG)is a new deep coal mining technology.By using this technology,the broken roadway roof is strengthened,and roof cutting is applied to cut off stress transfer between the roadway and gob to ensure the collapse of the overlying strata.The roadway is automatically formed owing to the broken expansion characteristics of the collapsed strata and mining pressure.Taking the Suncun Coal Mine as the engineering background,the control effect of this new technology on roadways was studied.To compare the law of stress evolution and the surrounding rock control mechanisms between AFR and traditional gob-side entry driving,a comparative study of geomechanical model tests on the above methods was carried out.The results showed that the new technology of AFR by RCBG effectively reduced the stress concentration of the roadway compared with gob-side entry driving.The side abutment pressure peak of the solid coal side was reduced by 24.3%,which showed an obvious pressure-releasing effect.Moreover,the position of the side abutment pressure peak was far from the solid coal side,making it more beneficial for roadway stability.The deformation of AFR surrounding rock was also smaller than the deformation of the gob-side entry driving by the overload test.The former was more beneficial for roadway stability than the latter under higher stress conditions.Field application tests showed that the new technology can effectively control roadway deformation.Moreover,the technology reduced roadway excavation and avoided resource waste caused by reserved coal pillars. 展开更多
关键词 automatically formed roadway Roof cutting Bolt grouting Roadway control Model test
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Testing Forms in Web Applications Automatically 被引量:2
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作者 XU Lei XU Baowent 《Wuhan University Journal of Natural Sciences》 EI CAS 2006年第3期561-566,共6页
Forms enhance both the dynamic and interactive abilities of Web applications and the system complexity. And it is especially important to test forms completely and thoroughly. Therefore, this paper discusses how to ca... Forms enhance both the dynamic and interactive abilities of Web applications and the system complexity. And it is especially important to test forms completely and thoroughly. Therefore, this paper discusses how to carry out the form testing by different methods in the related testing phases. Namely, at first, automatically abstracting forms in the Web pages by parsing the HTML documents; then, ohtai ning the testing data with a certain strategies, such as by requirement specifications, by mining users' hefore input informarion or by recording meehanism; and next executing the testing actions automatically due to the well formed test cases; finally, a case study is given to illustrate the convenient and effective of these methods. 展开更多
关键词 Web application form testing testing process automatic testing
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Automatic well test interpretation based on convolutional neural network for a radial composite reservoir 被引量:5
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作者 LI Daolun LIU Xuliang +2 位作者 ZHA Wenshu YANG Jinghai LU Detang 《Petroleum Exploration and Development》 2020年第3期623-631,共9页
An automatic well test interpretation method for radial composite reservoirs based on convolutional neural network(CNN) is proposed, and its effectiveness and accuracy are verified by actual field data. In this paper,... An automatic well test interpretation method for radial composite reservoirs based on convolutional neural network(CNN) is proposed, and its effectiveness and accuracy are verified by actual field data. In this paper, based on the data transformed by logarithm function and the loss function of mean square error(MSE), the optimal CNN is obtained by reducing the loss function to optimize the network with "dropout" method to avoid over fitting. The trained optimal network can be directly used to interpret the buildup or drawdown pressure data of the well in the radial composite reservoir, that is, the log-log plot of the given measured pressure variation and its derivative data are input into the network, the outputs are corresponding reservoir parameters(mobility ratio, storativity ratio, dimensionless composite radius, and dimensionless group characterizing well storage and skin effects), which realizes the automatic initial fitting of well test interpretation parameters. The method is verified with field measured data of Daqing Oilfield. The research shows that the method has high interpretation accuracy, and it is superior to the analytical method and the least square method. 展开更多
关键词 radial composite reservoir well testing interpretation convolutional neural network automatic interpretation artificial intelligence
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Study on Test Compaction in High-Level Automatic Test Pattern Generation (ATPG) Platform 被引量:1
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作者 Ayub Chin Abdullah Chia Yee Ooi 《Circuits and Systems》 2013年第4期342-349,共8页
Advancements in semiconductor technology are making gate-level test generation more challenging. This is because a large amount of detailed structural information must be processed in the search process of automatic t... Advancements in semiconductor technology are making gate-level test generation more challenging. This is because a large amount of detailed structural information must be processed in the search process of automatic test pattern generation (ATPG). In addition, ATPG needs to deal with new defects caused by process variation when IC is shrinking. To reduce the computation effort of ATPG, test generation could be started earlier at higher abstraction level, which is in line with top-down design methodology that has become more popular nowadays. In this research, we employ Chen’s high-level fault model in the high-level ATPG. Besides shorter ATPG time as shown in many previous works, our study showed that high-level ATPG also contributes to test compaction. This is because most of the high-level faults correlate with the gate-level collapsed faults especially at input/output of the modules in a circuit. The high-level ATPG prototype used in our work is mainly composed by constraint-driven test generation engine and fault simulation engine. Experimental result showed that more reduced/compact test set can be generated from the high-level ATPG. 展开更多
关键词 automatic test Pattern Generation (atPG) Constraint Logic Programming (CLP) Verilator Circuit-Under-test (CUT) test COMPACTION
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Reducing Item Exposure in Computerized Adaptive Testing Systems Using Automatic Item Generation 被引量:1
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作者 Harutyun Terteryan 《Computer Technology and Application》 2014年第1期21-24,共4页
This paper studies the technics of reducing item exposure by utilizing automatic item generation methods. Known test item calibration method uses item parameter estimation with the statistical data, collected during e... This paper studies the technics of reducing item exposure by utilizing automatic item generation methods. Known test item calibration method uses item parameter estimation with the statistical data, collected during examinees prior testing. Disadvantage of the mentioned item calibration method is the item exposure; when test items become familiar to the examinees. To reduce the item exposure, automatic item generation method is used, where item models are being constructed based on already calibrated test items without losing already estimated item parameters. A technic of item model extraction method from the already calibrated and therefore exposed test items described, which can be used by the test item development specialists to integrate automatic item generation principles with the existing testing applications. 展开更多
关键词 Item exposure calibration IRT (item response theory) adaptive testing automatic item generation item model.
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A Method for Modeling the Virtual Instrument Automatic Test System Based on the Petri Net 被引量:1
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作者 马敏 陈光 《Journal of Electronic Science and Technology of China》 2005年第2期157-160,共4页
Virtual instrument is playing the important role in automatic test system. This paper introduces a composition of a virtual instrument automatic test system and takes the VXIbus based a test software platform which is... Virtual instrument is playing the important role in automatic test system. This paper introduces a composition of a virtual instrument automatic test system and takes the VXIbus based a test software platform which is developed by CAT lab of the UESTC as an example. Then a method to model this system based on Petri net is proposed. Through this method, we can analyze the test task scheduling to prevent the deadlock or resources conflict. At last, this paper analyzes the feasibility of this method. 展开更多
关键词 virtual instrument automatic test system VXIBUS Petri net model system
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An Automatic Testing System of Scheduling Strategies in Real-Time UNIX
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作者 Qin Xiao, Pang Liping & Han Zongfen Department of Computer Science, Huazhong University of Science and Technology, Wuhan 430074, P. R. China 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2001年第2期59-62,共4页
This paper proposes a formal model of the automatic testing system for scheduling strategies in real-time UNIX and describes the algorithm of the key part of the system. The model of the system is an important technol... This paper proposes a formal model of the automatic testing system for scheduling strategies in real-time UNIX and describes the algorithm of the key part of the system. The model of the system is an important technology of the automatization of software development. According to the model presented in the paper, many different kinds of automatic testing systems can be designed and developed easily. At the end of the paper, the prototype proves the feasibility of the model and design. 展开更多
关键词 ALGORITHMS automatic testing Real time systems SCHEDULING Software prototyping
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Automatic lifting system design and application of large load powered support test rig
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作者 LIU Xin-ke 《Journal of Coal Science & Engineering(China)》 2012年第4期428-431,共4页
This paper presented a design of an automatic lifting system. It is used for large load powered support and improves the old method wherein powered support lifting depends on manual control. This system applies a high... This paper presented a design of an automatic lifting system. It is used for large load powered support and improves the old method wherein powered support lifting depends on manual control. This system applies a high accuracy gear shunt motor to match the flow for 4 lifting cylinders, and also allocates bypass throttles to realize automatic lifting. Through the dis- placement sensor feedback the height deviation among 4 lifting cylinders during the whole lifting process, when the deviation is up to the sitting value, the corresponding bypass throttle is operated immediately to reduce the deviation, so that the moving platform of the powered support would not be stuck. Through real application, it is shown that this system can realize automatic lifting of powered support; the lifting speed is controlled between 5 and 10 mm/s, and the final aligning accuracy is up to 1 mm. 展开更多
关键词 powered support automatic lift hydraulic system design test rig large load
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Aware Time in Bug Fix—A Novel Automatic Test Case Selection for Prioritization of Version Control
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作者 G. Parkavi D. Jeya Mala 《Circuits and Systems》 2016年第7期1140-1154,共15页
The supreme goal of the Automatic Test case selection techniques is to guarantee systematic coverage, to recognize the usual error forms and to lessen the test of redundancy. It is unfeasible to carry out all the test... The supreme goal of the Automatic Test case selection techniques is to guarantee systematic coverage, to recognize the usual error forms and to lessen the test of redundancy. It is unfeasible to carry out all the test cases consistently. For this reason, the test cases are picked and prioritize it. The major goal of test case prioritization is to prioritize the test case sequence and finds faults as early as possible to improve the efficiency. Regression testing is used to ensure the validity and the enhancement part of the changed software. In this paper, we propose a new path compression technique (PCUA) for both old version and new version of BPEL dataset. In order to analyze the enhancement part of an application and to find an error in an enhancement part of an application, center of the tree has been calculated. Moreover in the comparative analysis, our proposed PCUA- COT technique is compared with the existing XPFG technique in terms of time consuming and error detection in the path of an enhancement part of BPEL dataset. The experimental results have been shown that our proposed work is better than the existing technique in terms of time consuming and error detection. 展开更多
关键词 automatic test Cases PRIORITIZatION Regression testing BPEL Dataset Composite Services PCUA test Tree COT test Tree
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Test Method for Evaluating the Cleaning Performance of Proteases in Automatic Dishwashing Detergent
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作者 Xu Lu Ji Jing Pieter Augustinus 《China Detergent & Cosmetics》 2021年第2期69-73,共5页
A test method was developed to better evaluate the cleaning performance of protease in Chinese automatic dishwashing detergent(ADD)and differentiate the washing performance of different ADD formulations on protein sta... A test method was developed to better evaluate the cleaning performance of protease in Chinese automatic dishwashing detergent(ADD)and differentiate the washing performance of different ADD formulations on protein stains.Steamed egg stain,which was a Chinese-consumers-relevant soil,was used as monitor.The response curves of the stain to different amounts of protease were measured under laboratory conditions,and the stain removal ability of commercially available ADDs was tested with this method.The results showed that the soil removal rate of ADD without protease was less than 10%,and the soil removal rate increased with the increase of protease dosage in the range of 0~2.0%.Steamed egg stain had a good response to protease,and it could effectively distinguish the cleaning performance of commercial ADDs.The test method could be used in the development,screening and evaluation of ADD formulations. 展开更多
关键词 PROTEASE automatic dishwashing DETERGENT stain REMOVAL test method
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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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Application of clutch to clutch gear shift technology for a new automatic transmission 被引量:5
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作者 鲁曦 王书翰 +1 位作者 刘艳芳 徐向阳 《Journal of Central South University》 SCIE EI CAS 2012年第10期2788-2796,共9页
For the purpose of engineering development for a new 8-step speed automatic transmission,a simplified dynamic model for this gearbox was established and key parameters which affected the shift quality were analyzed.Ai... For the purpose of engineering development for a new 8-step speed automatic transmission,a simplified dynamic model for this gearbox was established and key parameters which affected the shift quality were analyzed.Aiming at four different shift types,the ideal characteristics of shift clutch and engine control were set up.By using torque estimation method,PI slip control algorithm and engine coordinated control principle,the control model and transmission controller were well developed for three shift phases which included rapid-fill phase,torque phase and inertia phase.The testing environment on the rig and prototype vehicle level was built and the testing results obtained in ultimate condition could verify the accuracy and feasibility of this shift control strategy.The peak jerk during shift process was controlled within ±2 g/s where the smooth gearshift was obtained.The development proposal and algorithm have a high value for engineering application. 展开更多
关键词 automatic transmission shift clutch shift strategy vehicle testing peak jerk gearshift control algorithm
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基于ATE的高速DAC射频参数SFDR测试技术优化
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作者 沈锺杰 张一圣 +1 位作者 孔锐 王建超 《现代电子技术》 北大核心 2024年第2期16-20,共5页
利用集成电路自动测试设备(ATE)测试高速DAC射频参数时,由于ATE测试板PCB走线较长、损耗较大以及机台提供的信号抖动比实装大等原因,导致ATE上高速DAC射频参数测试指标低于实装测试值。为此,文中介绍DAC电路的工作原理和测试方法;其次... 利用集成电路自动测试设备(ATE)测试高速DAC射频参数时,由于ATE测试板PCB走线较长、损耗较大以及机台提供的信号抖动比实装大等原因,导致ATE上高速DAC射频参数测试指标低于实装测试值。为此,文中介绍DAC电路的工作原理和测试方法;其次为解决上述问题,对测试码的生成以及PCB的布局等进行一系列改进,并将改进前后的测试值与典型值进行对比。结果表明,改进措施成效显著,大大优化了高速DAC射频参数的测试指标,使得SFDR等高频DAC动态类参数指标接近或达到实装测试值。 展开更多
关键词 集成电路 自动测试设备(atE) 高速数模转换器 射频参数 SFDR参数 测试码 PCB测试板
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呼和浩特地铁2号线ATS系统主备中心的设计与实现 被引量:1
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作者 吕涛 周公建 《铁道通信信号》 2023年第7期60-66,72,共8页
呼和浩特城市轨道交通工程首次采用云平台统一承载业务,实现了列车自动监控系统(ATS)在云平台上的集成运行。为确保信号系统入云后整个系统运行的稳定性和可靠性,设计部署主备控制中心。结合呼和浩特市ATS系统主备控制中心的建设要求,... 呼和浩特城市轨道交通工程首次采用云平台统一承载业务,实现了列车自动监控系统(ATS)在云平台上的集成运行。为确保信号系统入云后整个系统运行的稳定性和可靠性,设计部署主备控制中心。结合呼和浩特市ATS系统主备控制中心的建设要求,分析云平台相关设计需求;提出一套基于云平台的主备控制中心切换方案,并对主备控制中心之间、中心与云外设备之间的数据流向进行分析,实现了主备中心相关功能以及在云平台上的业务应用部署,解决了业务系统转为云平台部署后所带来的问题,为其他轨道交通主备中心云平台建设提供参考。 展开更多
关键词 云平台 信号系统 主用中心 备用中心 列车自动监控系统
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ATS与CI接口码位自动输出工具的设计与实现
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作者 周泓旭 《现代工业经济和信息化》 2023年第5期115-116,共2页
提出了一种针对CBTC(基于通信的列车自动控制系统)中ATS子系统与CI(联锁)子系统接口码位间配置文件自动输出的设计方案,通过读取联锁提供的ATS与联锁接口码位表,重新定义设备数据存储结构,将接口方案转化为输出控制逻辑。提供人机交互... 提出了一种针对CBTC(基于通信的列车自动控制系统)中ATS子系统与CI(联锁)子系统接口码位间配置文件自动输出的设计方案,通过读取联锁提供的ATS与联锁接口码位表,重新定义设备数据存储结构,将接口方案转化为输出控制逻辑。提供人机交互界面、检查输入文件的正确性和完整性,满足多个联锁区的ATS与联锁接口码位配置文件批量输出的需求,从而减少数据制作强度,提高配置的准确性。 展开更多
关键词 ats CI 自动测试 接口码位
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Investigation into the automatic recognition of time series precursor of earthquakes
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作者 黄汉明 范洪顺 +1 位作者 边银菊 邹立晔 《Acta Seismologica Sinica(English Edition)》 EI CSCD 1998年第5期87-96,共10页
In this paper, a new method of quantitative description of earthquake precursors is proposed; by this method, the precursory pattern of time series can be quantitatively described with a two-dimensional matrix. On thi... In this paper, a new method of quantitative description of earthquake precursors is proposed; by this method, the precursory pattern of time series can be quantitatively described with a two-dimensional matrix. On this basis, a method of automatic recognition or automatic acquirement of precursory pattern, called simply the AA method, is put forward. Then, taking North China region as an example, various seismological precursors such as the frequency, energy, b -value, etc . and various nonlinear parameter precursors such as the capacity dimension, information dimension, correlation dimension, Hurst index and its difference, etc. are analyzed and the 8 time series so obtained are recognized automatically using the proposed precursory pattern and AA method. Besides, C-method tests and very rigorous HF (history and future) tests are made. The result shows that the R-value of prediction efficacy assessment is fairly high. 展开更多
关键词 earthquake prediction precursory pattern automatic recognition C-method test HF test
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