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CONTROL WORK IN CLOSE RANGE PHOTOGRAMMETRY 被引量:2
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作者 FENG Wenhao 《Geo-Spatial Information Science》 2001年第4期66-72,共7页
The purpose, classification, required accuracy and surveying methods of control work for close range photogrammetry have been briefly stated. The different methods for definition of space, object coordinate system are... The purpose, classification, required accuracy and surveying methods of control work for close range photogrammetry have been briefly stated. The different methods for definition of space, object coordinate system are also reviewed. It is suggested that the habitu-ally-practised rotation angle system for aerophotogrammetry in China should be used for the future teaching and resaarching work in the close range photogrammetry, and that the rotation angle system for terrestrial deformation photogrammetry should be left out in order to avoid the confuse and reduce the amount of expanse for making softwares. It has been emphasized that there are three improtant aspects in the close range control work with high accurary using the conventional method of engineering surveying: the use of standard scale for measurement of distance between two general stations, the accurate determination of start direction line between two general stations and the handling method of influence of 2C change. A method for setting up industrial surveying control net with extra-high accuracy ±(0.05–0.20) mm is presented by the author. This kind of industrial control net is necessary for batch process of large industrial components with purposes of measurement, inspect and lofting. There are some special methods of control work in the close range photogrammetry, including two methods presented by the author. 展开更多
关键词 close range photogrammetry control work high accuracy industrial control net
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Comparison of erosion and erosion control works in Macedonia,Serbia and Bulgaria 被引量:1
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作者 Ivan Blinkov Stanimir Kostadinov Ivan Ts.Marinov 《International Soil and Water Conservation Research》 SCIE 2013年第3期15-28,共14页
While soils are as essential to human society as air and water,soil degradation has not received nearly as much attention as the threats to these other elements.On the map of water erosion of Europe,Southern Europe is... While soils are as essential to human society as air and water,soil degradation has not received nearly as much attention as the threats to these other elements.On the map of water erosion of Europe,Southern Europe is red"colored".Erosion in the Balkan countries,through both on and offsite effects is a major cause of soil and water degradation.This paper compares erosion control works in several countries from the Balkan region(Macedonia,Serbia,and Bulgaria).The basis for comparative analyses was various country reports as well as available published papers.Quantitative method-text analyze method was used for these study.Natural conditions in the Balkan countries contribute to the appearance of various erosion forms and the intensity of the erosion processes.Over the history of these countries,people who settled this region used the available natural resources to fill their needs(tree cutting,incorrect plugging,overgrazing),which contributed to soil erosion.Organized erosion control works in the Balkans started in the beginning of the 20th century(1905 in Bulgaria).The highest intensity of erosion control works were carried out during the period 1945-1990.Various erosion control works were launched.Bulgaria had a large anti-erosion afforestation,almost 1 million ha.Bulgaria's ecological river restoration approach has been in use for almost 50 years.Serbia contributed significant erosion and torrent control works on hilly agricultural areas.Specific screen barrages and afforestation on extremely dry areas are characteristic in Macedonia.A common characteristic for all countries is a high decrease in erosion control works in the last 20 years. 展开更多
关键词 EROSION Erosion control works BALKAN
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CONSTANT WORK-POINT CONTROL FOR PARALLEL HYBRID SYSTEM WITH CAPACITOR ACCUMULATOR IN HYDRAULIC EXCAVATOR 被引量:4
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作者 ZHANG Yanting WANG Qingfeng XIAO Qing FU Qiang 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2006年第4期505-508,共4页
Limitations of various accumulators in hybrid hydraulic excavator are analyzed. A program using capacitor as the accumulator based on constant work-point control is put forward. A simulating experimental system of hyb... Limitations of various accumulators in hybrid hydraulic excavator are analyzed. A program using capacitor as the accumulator based on constant work-point control is put forward. A simulating experimental system of hybrid construction machinery is established, and experimental study on constant work-point control for parallel hybrid system with capacitor accumulator is carried out using the pressure and flow rate derived from boom cylinder of hydraulic excavator in actual work as the simulating loads. A program of double work-point control is proposed and proved by further experiments. 展开更多
关键词 Hybrid Hydraulic excavator Capacitor accumulator Constant work-point control Double work-point control
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A Combining Call Admission Control and Power Control Scheme for D2D Communications Underlaying Cellular Networks 被引量:7
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作者 Xujie Li Wenna Zhang +1 位作者 Honglang Zhang Wenfeng Li 《China Communications》 SCIE CSCD 2016年第10期137-145,共9页
As device-to-device(D2D) communications usually reuses the resource of cellular networks, call admission control(CAC) and power control are crucial problems. However in most power control schemes, total data rates or ... As device-to-device(D2D) communications usually reuses the resource of cellular networks, call admission control(CAC) and power control are crucial problems. However in most power control schemes, total data rates or throughput are regarded as optimization criterion. In this paper, a combining call admission control(CAC) and power control scheme under guaranteeing QoS of every user equipment(UE) is proposed. First, a simple CAC scheme is introduced. Then based on the CAC scheme, a combining call admission control and power control scheme is proposed. Next, the performance of the proposed scheme is evaluated. Finally, maximum DUE pair number and average transmitting power is calculated. Simulation results show that D2 D communications with the proposed combining call admission control and power control scheme can effectively improve the maximum DUE pair number under the premise of meeting necessary QoS. 展开更多
关键词 device-to-device(D2D) call admission control power control cellular networks
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Evaluation of Merge Control Strategies at Interstate Work Zones under Peak and Off-Peak Traffic Conditions 被引量:1
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作者 Ossama E. Ramadan Virginia P. Sisiopiku 《Journal of Transportation Technologies》 2016年第3期118-130,共13页
Maintenance and rehabilitation projects of interstate facilities typically mandate lane closures. Lane closures require merging maneuvers that often result in reduced speeds and traffic bottlenecks. Work zone impacts ... Maintenance and rehabilitation projects of interstate facilities typically mandate lane closures. Lane closures require merging maneuvers that often result in reduced speeds and traffic bottlenecks. Work zone impacts on traffic operations are magnified when project durations are extended. Conventionally, work zone traffic control plans are developed to address work zone impacts. This study evaluated various merge control strategies at interstate work zones peak and off-peak traffic conditions and summarized related impacts. A comprehensive microscopic simulation model was developed in full consideration of driver/vehicle behavior at work zones. The analysis of simulation results revealed that merge control strategies, when implemented during peak and off-peak conditions, can preserve the level of service and provide favorable mobility, safety, and environmental impacts. In addition, results indicate that transportation agencies’ practice of scheduling work zone activities during the off-peak may not be the most optimum approach. Overall, the findings of this study highlight the need for evaluation of work zone scheduling practices in full consideration of agency, user, and project costs. 展开更多
关键词 Traffic Simulation BOTTLENECKS work Zone Traffic control Traffic Congestion
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How Work Organization Affects the Prevalence of WMSDs: A Case-control Study 被引量:12
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作者 LIU Lu CHEN Song Gen +6 位作者 TANG Shi Chuan WANG Sheng HE Li Hua GUO Ze Hua LI Jing Yun YU Shan Fa WANG Zhong Xu 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2015年第9期627-633,共7页
Objective In this study, we aimed at exploring the association between work-related musculoskeletal disorders(WMSDs) and work organization based on a case-control study. Methods A total of 1938 workers who claimed t... Objective In this study, we aimed at exploring the association between work-related musculoskeletal disorders(WMSDs) and work organization based on a case-control study. Methods A total of 1938 workers who claimed to suffer from WMSDs were selected from Beijing, Henan, Hubei, and the Guangdong province. The control group consisted of 2009 workers employed in similar industries without severe disease or musculoskeletal discomforts. We used a modified version of the questionnaire developed by the NMQ and the DMQ to investigate individual and work-related factors. Results A total of 13 variables(P〈0.1) were selected by the chi-square test and finally, 7 variables entered into the equation, with 6 variables reaching statistical significance(P〈0.05). The odds ratios(OR) of 'work changing with season' and 'sufficient rest time' did not reach 1(0.749 and 0.441, respectively). In addition, 'sufficient rest time' seemed to be the stronger protective factor according to its higher standardized coefficient. And 'repetitive work every minute', 'constantly repetitive work'(every day), 'shortage of site personnel', and 'often switching shifts with others' seemed to be the risk factors. Conclusion Work organization may have comprehensive effects on the occurrence of WMSDs. This pattern of associations suggests that further investigation into the mechanism of how work organization affects the prevalence of WMSDs is required. 展开更多
关键词 WMSDs work organization Case-control study Prevalence Risk factors
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Synchronization in a fractional-order dynamic network with uncertain parameters using an adaptive control strategy 被引量:1
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作者 Lin DU Yong YANG Youming LEI 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2018年第3期353-364,共12页
This paper studies synchronization of all nodes in a fractional-order complex dynamic network. An adaptive control strategy for synchronizing a dynamic network is proposed. Based on the Lyapunov stability theory, this... This paper studies synchronization of all nodes in a fractional-order complex dynamic network. An adaptive control strategy for synchronizing a dynamic network is proposed. Based on the Lyapunov stability theory, this paper shows that tracking errors of all nodes in a fractional-order complex network converge to zero. This simple yet prac- tical scheme can be used in many networks such as small-world networks and scale-free networks. Unlike the existing methods which assume the coupling configuration among the nodes of the network with diffusivity, symmetry, balance, or irreducibility, in this case, these assumptions are unnecessary, and the proposed adaptive strategy is more feasible. Two examples are presented to illustrate effectiveness of the proposed method. 展开更多
关键词 fractional-order chaotic system SYNCHRONIZATION complex dynamic net-work adaptive control
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A Study on Control System of Robot Working Unit for Automatically Welding Nipples onto Header of Boiler
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作者 陶谦 于树锋 +1 位作者 姜山 曹佩军 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 1996年第2期64-68,共5页
The difficult problem of automatically welding nipples onto the header is first analyzed in this paper, and then the overall structure and operating principle of the robot working unit are introduced. The robot and th... The difficult problem of automatically welding nipples onto the header is first analyzed in this paper, and then the overall structure and operating principle of the robot working unit are introduced. The robot and the measuring device are located by employing the traveling lorry, and this unit enables the robot to adjust the tracks according to the errors received from the measuring device, and then the nipples are welded properly. This paper emphases on the development of the master-slave control system, in which the prograrmmable Logic Controller (PLC) is used as the master computer. 展开更多
关键词 ss:Header nipple PLC ROBOT control WELDING working UNIT master-slave control
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Assessing Work Zone Traffic Control Options for 3-to-1 Lane Closures 被引量:1
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作者 Troyee Saha Virginia P. Sisiopiku 《Journal of Transportation Technologies》 2020年第1期50-64,共15页
The presence of highway construction zones hinders mobility and affects traffic operations. A 2002 study by Wunderlich & Hardesty reported that nearly 20% of the National Highway System roads have scheduled constr... The presence of highway construction zones hinders mobility and affects traffic operations. A 2002 study by Wunderlich & Hardesty reported that nearly 20% of the National Highway System roads have scheduled construction work during the peak construction season. Additionally, approximately 24% of non-recurring delays on freeways are caused by work zones. To minimize time lost by travelers due to work zone induced traffic congestion, it is important to efficiently plan temporary traffic control (TTC) at work zones. Earlier research conducted by Sisiopiku & Ramadan, 2017 confirms that the majority of State Departments of Transportation currently rely on their earlier experience when planning for work zones, rather than consider operational and safety impacts. Using a study corridor in Birmingham, Alabama as a test bed, this study investigated the operational impacts of TTC options for work zones with 3-to-1 lane drop configuration using traffic data collected from the Alabama Department of Transportation. The VISSIM simulation platform was used to conduct the experiments. The experimental design considered two TTC strategies (i.e., static late and early merge) under 3-to-1 lane drop configuration for work-space length of 500 ft for long- and short-term lane closures. The study concluded that the 3-to-1 lane-drop configuration should not be scheduled for long-term duration. Maintenance work can be scheduled from midnight to early morning and under the 3-to-1 lane closure scenario the performance of early and late merge traffic control is similar. Overall, this study used simulation modeling to compare the effectiveness of two traffic control strategies at work zones on the basis of different performance measures. The results provide information about the impact of each control strategy on density, speed, travel time etc. They also help determine what time of the day is best for lane closings in order to reduce adverse impacts from capacity reduction. Thus, the findings are expected to provide valuable guidance for agencies responsible for planning, design, and operations of work zones in the future. 展开更多
关键词 work Zone Traffic control Early MERGE LATE MERGE VISSIM Simulation
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Robot Position Control Using Force Information for Cooperative Work in Remote Robot Systems with Force Feedback 被引量:1
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作者 Satoru Ishikawa Yutaka Ishibashi +1 位作者 Pingguo Huang Yuichiro Tateiwa 《International Journal of Communications, Network and System Sciences》 2021年第1期1-13,共13页
This paper proposes robot position control using force information for cooperative work between two remote robot systems with force feedback in each of which a user operates a remote robot by using a haptic interface ... This paper proposes robot position control using force information for cooperative work between two remote robot systems with force feedback in each of which a user operates a remote robot by using a haptic interface device while observing work of the robot with a video camera. We also investigate the effect of the proposed control by experiment. As cooperative work, we deal with work in which two robots carry an object together. The robot position control using force information finely adjusts the position of the robot arm to reduce the force applied to the object. Thus, the purpose of the control is to avoid large force so that the object is not broken. In our experiment, we make a comparison among the following three cases in order to clarify how to carry out the control effectively. In the first case, the two robots are operated manually by a user with his/her both hands. In the second case, one robot is operated manually by a user, and the other robot is moved automatically under the proposed control. In the last case, the object is carried directly by a human instead of the robot which is operated by the user in the second case. As a result, experimental results demonstrate that the control can help each system operated manually by the user to carry the object smoothly. 展开更多
关键词 Remote Robot System Haptic Interface Device Force Feedback Cooperative work Robot Position control EXPERIMENT
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WORKING LIQUID PRESSURE AND ITS CONTROL IN HYDRAULIC DRAWING PROCESSES OF CUPS
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作者 Liu Yan,Bai Shujie,Kang Guosheng,Li Tianyou (Department of Mechanical Engineering, Taiyuan Heavy Machinery Institute) 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2001年第3期279-281,285,共4页
A method of setting up a pressure-stroke characteristic of the working liquid in hydraulic drawing is studied. A pressure-stroke characteristic and software for controlling its forming process are also developed. An... A method of setting up a pressure-stroke characteristic of the working liquid in hydraulic drawing is studied. A pressure-stroke characteristic and software for controlling its forming process are also developed. And a set of pressure controlling devices with PLC as a central processor are designed. It can be got from the relevant experiments that the pressure-stroke characteristic is correct and its control for forming process is available. 展开更多
关键词 Hydraulic drawing working liquid pressure Pressure control
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Relationship among Eating Behavior, Effortful Control, and Working Memory in Female Young Adults
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作者 Katsumasa Momoi Kumiko Ohara +4 位作者 Yoshimitsu Okita Tomoki Mase Chiemi Miyawaki Tomoko Fujitani Harunobu Nakamura 《Health》 CAS 2016年第12期1187-1194,共9页
The management of eating behavior plays an important role in health maintenance. In this study, we investigated the relationship between eating behavior and effortful control in female young adults. Participants compl... The management of eating behavior plays an important role in health maintenance. In this study, we investigated the relationship between eating behavior and effortful control in female young adults. Participants completed the questionnaire measures of effortful control and eating behaviors and Stroop cognitive interference task. The results showed that restrained eating was positively correlated with activation control;emotional eating was negatively correlated with inhibitory control and attentional control;external eating was negatively correlated with inhibitory, activation, and attentional control. The scores for activation control and restrained eating were higher for participants with a low Stroop error rate than for those with a high Stroop error rate. These results indicate that restrained eating has a different association with effortful control than doing emotional and external eating. 展开更多
关键词 Executive Function working Memory Effortful control Eating Behavior
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Humanoid Based Intelligence Control Strategy of Plastic Cement Die Press Work-Piece Forming Process for Polymer Plastics
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作者 Dekuan Liu Shuang Jin Hu Xu 《Journal of Materials Science and Chemical Engineering》 2016年第6期9-16,共8页
The plastic cement belongs to a sort of polymer material, the chemical composition is very complex, and the plastic cement work-piece is generally manufactured by die press forming. Aimed at being difficult to control... The plastic cement belongs to a sort of polymer material, the chemical composition is very complex, and the plastic cement work-piece is generally manufactured by die press forming. Aimed at being difficult to control in parameters of forming process, the paper explored the humanoid based intelligence control strategy. In the paper, it made the anatomy in control puzzle resulted in uncertainty such as chemical component of plastic cement etc., summarized up the characteristic of cybernetics in forming process, researched on the humanoid based intelligence control strategy, and constructed the control algorithm of forming process in plastic cement work-piece. Taking the process experiment of temperature and pressure control as an example, it validated the good dynamic and static control quality through simulation of control algorithm constructed in this paper. The experimental results show that the control algorithm explored in this paper is reasonably available. 展开更多
关键词 Plastic Cement Polymer Plastics Die Press work-Piece Forming Process Humanoid Based Intelligence control
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基于SolidWorks二次开发的三维实时运动仿真方法 被引量:6
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作者 黄晓辰 张明路 +2 位作者 李满宏 孙凌宇 张小俊 《机械设计》 CSCD 北大核心 2014年第12期12-15,共4页
针对机器人三维实时运动仿真常用方法中不能与控制系统开发平台相融合、缺乏算法支持的问题,以用于检测压力容器的检测机器人为研究对象,设计出针对该机器人的三维实时控制系统软件。此软件将控制系统与三维实时仿真平台相融合,不仅能... 针对机器人三维实时运动仿真常用方法中不能与控制系统开发平台相融合、缺乏算法支持的问题,以用于检测压力容器的检测机器人为研究对象,设计出针对该机器人的三维实时控制系统软件。此软件将控制系统与三维实时仿真平台相融合,不仅能够远程对检测机器人生成并下达控制指令,而且利用Visual C#软件对Solid Works软件二次开发后形成的三维实时仿真平台,对机器人的运动状态进行实时仿真。现场使用结果表明,使用此软件能够安全可靠地对压力容器进行检测,三维实时仿真平台能有效提高仿真的精确度,实现对检测机器人运动状态进行全方位观测。 展开更多
关键词 机器人 控制系统 SOLIDworkS二次开发 三维实时仿真
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QoE Assessment of Group Synchronization Control Scheme with Prediction in Work Using Haptic Media 被引量:1
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作者 Pingguo Huang Yutaka Ishibashi +1 位作者 Norishige Fukushima Shinji Sugawara 《International Journal of Communications, Network and System Sciences》 2012年第6期321-331,共11页
This paper proposes a group synchronization control scheme with prediction in work using haptic media. The scheme adjusts the output timing among multiple terminals and keeps the interactivity high. It outputs positio... This paper proposes a group synchronization control scheme with prediction in work using haptic media. The scheme adjusts the output timing among multiple terminals and keeps the interactivity high. It outputs position information by predicting the future position later than the position included in the last-received information by a fixed amount of time. It also advances the output time of position information at each local terminal by the same amount of time. We deal with two different types of work using haptic media so as to demonstrate the effectiveness of the scheme. We assess the output quality of haptic media for the two types of work subjectively and objectively by Quality of Experience (QoE) assessment. We further clarify the relationship between subjective and objective assessment results. 展开更多
关键词 Group Synchronization control PREDICTION control HAPTIC MEDIA Remote Drawing Instruction Play with Building Blocks Collaborative work QOE ASSESSMENT
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LonWorks在电除尘器实验系统中的应用 被引量:2
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作者 王洋 王宁会 《仪器仪表学报》 EI CAS CSCD 北大核心 2001年第z2期280-281,共2页
本文论述了 L onworks现场总线在火电厂电除尘器实验系统中的应用。该系统以研究电除尘器稳态工作的条件为目的 ,要求完成对现场所有设备的监控、以及对现场所有数据的处理等功能。由于 L on Works的应用 ,满足了该实验系统的稳定性、... 本文论述了 L onworks现场总线在火电厂电除尘器实验系统中的应用。该系统以研究电除尘器稳态工作的条件为目的 ,要求完成对现场所有设备的监控、以及对现场所有数据的处理等功能。由于 L on Works的应用 ,满足了该实验系统的稳定性、开放性的要求 。 展开更多
关键词 现场总线控制系统 LONworkS
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基于Lon Works的PID控制器在过控系统中的应用 被引量:1
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作者 胡敦利 马秀坤 《仪器仪表学报》 EI CAS CSCD 北大核心 2003年第z1期323-325,共3页
本文介绍了一种基于 L on Works网络的 PID控制器的设计 ,分析了水位控制系统的构成 ,采用了带 Smith补偿的 PID算法 ,给出了控制器硬件实现原理及软件流程 ,将其用于实际的水位过程控制系统 。
关键词 LON workS 过程控制 Smith补偿 PID
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使用Component Works GPIB ActiveX控件快速组建基于VB环境的测试系统
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作者 薛红朝 张义忠 +1 位作者 孟晨 王坚 《国外电子测量技术》 2001年第z1期33-35,共3页
本文以组建GPIB的测试系统为例,介绍了在Visual Basic 5.0环境下,利用Component Works控件快速组建某测试系统的一种方法。详细说明了系统的组建过程及其应注意的一些问题。
关键词 Componentworks ACTIVEX控件 测试系统
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基于LonWorks技术的现代智能测控系统创新实验设计 被引量:2
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作者 高安邦 《哈尔滨理工大学学报》 CAS 2008年第3期1-4,共4页
指出该设计是"机电一体化"高新技术的最高端应用和最前沿发展领域,分析了该技术目前在国内外蓬勃发展的研究概况,给出了本集成设计中15项创新实验项目的主要内容、本设计实现的基本功能框图和物理连线结构框图、本设计的研究... 指出该设计是"机电一体化"高新技术的最高端应用和最前沿发展领域,分析了该技术目前在国内外蓬勃发展的研究概况,给出了本集成设计中15项创新实验项目的主要内容、本设计实现的基本功能框图和物理连线结构框图、本设计的研究重点和网络拓扑框图,说明了本设计的创新点和应用价值. 展开更多
关键词 LON works技术 智能网络测控 创新实验
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How to Strengthen the Prevention and Control of Animal Diseases in Animal Husbandry
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作者 ZHONGXiaowei 《外文科技期刊数据库(文摘版)自然科学》 2022年第8期099-102,共4页
In recent years, with the continuous acceleration of the development process of the animal husbandry and aquaculture industry, the scale of aquaculture shows the trend of expansion, and the continuous occurrence of an... In recent years, with the continuous acceleration of the development process of the animal husbandry and aquaculture industry, the scale of aquaculture shows the trend of expansion, and the continuous occurrence of animal diseases has become the main factor affecting the healthy development of the animal husbandry and aquaculture industry. How to better prevent and control animal diseases has become a difficult problem that the current animal husbandry and veterinary staff and aquaculture management personnel need to focus on. In view of the current occurrence and epidemic situation of animal epidemic diseases in animal husbandry, the types of epidemic diseases are gradually increased, and many infectious diseases present new epidemic characteristics with significantly increased drug resistance and gradually deteriorated prevention and control effect. Some zoonotic infectious diseases and the spread of major infectious diseases may cause a large number of animal deaths and great losses to the life and property safety of aquaculture personnel. Therefore, it is necessary to properly prevent and control the epidemic diseases during animal husbandry to effectively reduce the occurrence of animal epidemic diseases, ensure the healthy development of animals, and promote the healthy development of aquaculture industry. 展开更多
关键词 animal husbandry animal diseases prevention and control work
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