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The Design and Implementation of Multi-user Data Sharing Platform for Remote Monitoring System Based on Virtual Instruments
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作者 Ma GuoSheng Xia XiaoBo 《International Journal of Technology Management》 2014年第8期79-82,共4页
Remote data monitoring system which adopts virtual instrument usually applies data sharing, acquisition and remote transmission technology via internet. It is able to finish concurrent data acquisition and processing ... Remote data monitoring system which adopts virtual instrument usually applies data sharing, acquisition and remote transmission technology via internet. It is able to finish concurrent data acquisition and processing for multi-user and multi-task and also build a personalized virtual testing environment for more people but with fewer instruments. In this paper, we' 11 elaborate on the design and implementation of information sharing platform through a typical example of how to build multi-user concurrent virtual testing environment based on the virtnal software LabVIEW. 展开更多
关键词 virtual Testing Environment data Sharing Platform Concurrent data Acquisition and Transmission data Redundancy
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Application of Virtual Instrumentation in HL-2A DAPS
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作者 ZHAO Li CHEN Liaoyuan LUO Cuiwen LIYongge PAN Wei SONG Xianming WANG Minghong 《Southwestern Institute of Physics Annual Report》 2005年第1期79-81,共3页
HL-2A DAPS is a large scale special data system for HL-2A tokamak . Technology of network, communication, data acquisition, data processing, real-time display, data management and systems management have been used in ... HL-2A DAPS is a large scale special data system for HL-2A tokamak . Technology of network, communication, data acquisition, data processing, real-time display, data management and systems management have been used in this system. With higher quality products and lower design costs, virtual instrumentation has been widely used in HL-2A DAPS. Vh-tual instrumentation combines mainstream commercial technologies, with flexible software and a wide variety of measurement and control hardware. It's easily to create user-defined systems that meet the exact application needs for the experiment. 展开更多
关键词 virtual instrumentation LabVIEW data acquisition
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DEVELOPMENT OF VIRTUAL INSTRUMENT IN CHARACTERISTIC ANALYSIS OF ROTATING MACHINERY BASED ON INSTANTANEOUS FREQUENCY ESTIMATION 被引量:4
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作者 YangJiongming QinShuren +1 位作者 JiZhong GuoYu 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2004年第4期490-493,共4页
Based on the recently quick-developing time-frequency analysis (TFA)technique and virtual instrument (VI) technique, a virtual instrument in characteristic analysis ofrotating machinery is researched and developed suc... Based on the recently quick-developing time-frequency analysis (TFA)technique and virtual instrument (VI) technique, a virtual instrument in characteristic analysis ofrotating machinery is researched and developed successfully. By utilizing instantaneous frequencyestimation (IFE) theoretics of TFA technique, and based on IFE of peak searching on thetime-frequency spectrum, order analysis (OA) functions is put forward and implemented, such as orderspectrum, order spectrum matrix, order tracking, order tracking filtering, and order componentextraction, etc. Unlike the home and abroad existing popular characteristic analyzers, which needkey phasing devices such as shaft encoder, phase-locked loop (PLL), phase-locked multiple frequency,tachometer, etc, to implement constant angle sampling directly or indirectly, whereas thisinstrument only uses the vibration signal of rotating machinery to carry out OA. This instrumentmakes up the shortage of these traditional instruments in analyzing the non-stationary signal ofrun-up and run-down process of rotating machinery. Therefore, it is a great breakthrough for theexisting order analyzers. 展开更多
关键词 Rotating machinery Time-frequency analysis Instantaneous frequency Orderanalysis virtual instrument
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The Path to Reshaping the Structure and Chain System of the Publishing Industry in the Era of Big Data
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作者 DENG Liyan 《Management Studies》 2023年第6期322-328,共7页
Today,we are living in the era of“big data”where massive amounts of data are used for quantitative decisions and communication management.With the continuous penetration of big data-based intelligent technology in a... Today,we are living in the era of“big data”where massive amounts of data are used for quantitative decisions and communication management.With the continuous penetration of big data-based intelligent technology in all fields of human life,the enormous commercial value inherent in the data industry has become a crucial force that drives the aggregation of new industries.For the publishing industry,the introduction of big data and relevant intelligent technologies,such as data intelligence analysis and scenario services,into the structure and value system of the publishing industry,has become an effective path to expanding and reshaping the demand space of publishing products,content decisions,workflow chain,and marketing direction.In the integration and reconstruction of big data,cloud computing,artificial intelligence,and other related technologies,it is expected that a generalized publishing industry pattern dominated by virtual interaction will be formed in the future. 展开更多
关键词 the era of big data data analysis scenario service virtual publishing
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V–L decomposition of a novel full-waveform lidar system based on virtual instrument technique 被引量:2
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作者 徐帆 王元庆 《Chinese Physics B》 SCIE EI CAS CSCD 2015年第10期262-273,共12页
A novel three-dimensional(3D) imaging lidar system which is based on a virtual instrument technique is introduced in this paper. The main characteristics of the system include: the capability of modeling a 3D objec... A novel three-dimensional(3D) imaging lidar system which is based on a virtual instrument technique is introduced in this paper. The main characteristics of the system include: the capability of modeling a 3D object in accordance with the actual one by connecting to a geographic information system(GIS), and building the scene for the lidar experiment including the simulation environment. The simulation environment consists of four parts: laser pulse, atmospheric transport,target interaction, and receiving unit. Besides, the system provides an interface for the on-site experiment. In order to process the full waveform, we adopt the combination of pulse accumulation and wavelet denoising for signal enhancement.We also propose an optimized algorithm for data decomposition: the V-L decomposition method, which combines Vondrak smoothing and laser-template based fitting. Compared with conventional Gaussian decomposition, the new method brings an improvement in both precision and resolution of data decomposition. After applying V-L decomposition to the lidar system, we present the 3D reconstructed model to demonstrate the decomposition method. 展开更多
关键词 lidar system virtual instrument Vondrak smoothing laser-template based fitting
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Cost-Aware Multi-Domain Virtual Data Center Embedding 被引量:1
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作者 Xiao Ma Zhongbao Zhang Sen Su 《China Communications》 SCIE CSCD 2018年第12期190-207,共18页
Virtual data center is a new form of cloud computing concept applied to data center. As one of the most important challenges, virtual data center embedding problem has attracted much attention from researchers. In dat... Virtual data center is a new form of cloud computing concept applied to data center. As one of the most important challenges, virtual data center embedding problem has attracted much attention from researchers. In data centers, energy issue is very important for the reality that data center energy consumption has increased by dozens of times in the last decade. In this paper, we are concerned about the cost-aware multi-domain virtual data center embedding problem. In order to solve this problem, this paper first addresses the energy consumption model. The model includes the energy consumption model of the virtual machine node and the virtual switch node, to quantify the energy consumption in the virtual data center embedding process. Based on the energy consumption model above, this paper presents a heuristic algorithm for cost-aware multi-domain virtual data center embedding. The algorithm consists of two steps: inter-domain embedding and intra-domain embedding. Inter-domain virtual data center embedding refers to dividing virtual data center requests into several slices to select the appropriate single data center. Intra-domain virtual data center refers to embedding virtual data center requests in each data center. We first propose an inter-domain virtual data center embedding algorithm based on label propagation to select the appropriate single data center. We then propose a cost-aware virtual data center embedding algorithm to perform the intra-domain data center embedding. Extensive simulation results show that our proposed algorithm in this paper can effectively reduce the energy consumption while ensuring the success ratio of embedding. 展开更多
关键词 virtual data CENTER EMBEDDING MULTI-DOMAIN cost-aware LABEL PROPAGATION
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Study on Building and Modeling of Virtual Data of Xiaosha River Artificial Wetland 被引量:1
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作者 Qun Miao Lei Bian +1 位作者 Xipeng Wang CHang Xu 《Journal of Environmental Protection》 2013年第1期48-50,共3页
From the viewpoint of systems science, this article takes Xiaosha River artificial wetland under planning and construction as object of study based on the systems theory and takes the accomplished and running project ... From the viewpoint of systems science, this article takes Xiaosha River artificial wetland under planning and construction as object of study based on the systems theory and takes the accomplished and running project of Xinxuehe artificial wetland as reference. The virtual data of quantity and quality of inflow and the quality of outflow of Xiaosha River artificial wetland are built up according to the running experience, forecasting model and theoretical method of the reference project as well as the comparison analysis of the similarity and difference of the two example projects. The virtual data are used to study the building of forecasting model of BP neural network of Xiaosha River artificial wetland. 展开更多
关键词 Xiaosha RIVER artificial WETLAND virtual data BP NEURAL network
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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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Estimation of Natural Mortality Coefficient from Fish Abundance and Catch Data Using Virtual Population Analysis(VPA)
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作者 WANG Yingbin LIU Qun WANG Yanjun 《Journal of Ocean University of China》 SCIE CAS 2007年第1期53-59,共7页
Natural mortality coefficient (M) was estimated from fish abundance (N) and catch (C) data using a Virtual Population Analysis (VPA) model. Monte Carlo simulations were used to evaluate the impact of different error d... Natural mortality coefficient (M) was estimated from fish abundance (N) and catch (C) data using a Virtual Population Analysis (VPA) model. Monte Carlo simulations were used to evaluate the impact of different error distributions for the simulated data on the estimates of M. Among the four error structures (normal, lognormal, Poisson and gamma), simulations of normally dis-tributed errors produced the most viable estimates for M, with the lowest relative estimation errors (REEs) and median mean absolute deviations (MADs) for the ratio of the true to the estimated Ms. In contrast, the lognormal distribution had the largest REE value. Errors with different coefficients of variation (CV) were added to N and C. In general, when CVs in the data were less than 10%, reliable estimates of M were obtained. For normal and lognormal distributions, the estimates of M were more sensitive to the CVs in N than in C; when only C had error the estimates were close to the true. For Poisson and gamma distributions, opposite results were obtained. For instance, the estimates were more sensitive to the CVs in C than in N, with the largest REE from the scenario of error only in C. Two scenarios of high and low fishing mortality coefficient (F) were generated, and the simulation results showed that the method performed better for the scenario with low F. This method was also applied to the published data for the anchovy (Engraulis japonicus) of the Yellow Sea. Viable estimates of M were obtained for young groups, which may be explained by the fact that the great uncertainties in N and C observed for older Yellow Sea anchovy introduced large variation in the corresponding estimates of M. 展开更多
关键词 natural mortality COEFFICIENT FISH ABUNDANCE CATCH data virtual population analysis
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ROUTE SELECTION IN VIRTUAL CIRCUIT DATA NETWORKS BASED ON GENETIC ALGORITHMS
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作者 He Cuihong Ou Yishan(Guangdong Institute of Technology, Guangzhou 510090)Cheng Huowang(University of National Defense of Technology, Changsha 410073) 《Journal of Electronics(China)》 1997年第4期311-317,共7页
This paper addresses the problem of selecting a route for every pair of communicating nodes in a virtual circuit data network in order to minimize the average delay encountered by messages. The problem was previously ... This paper addresses the problem of selecting a route for every pair of communicating nodes in a virtual circuit data network in order to minimize the average delay encountered by messages. The problem was previously modeled as a network of M/M/1 queues. Agenetic algorithm to solve this problem is presented. Extensive computational results across a variety of networks are reported. These results indicate that the presented solution procedure outperforms the other methods in the literature and is effective for a wide range of traffic loads. 展开更多
关键词 ROUTE SELECTION virtual CIRCUIT data networks GENETIC ALGORITHMS
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Data Virtualization with SAP HANA Smart Data Access
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作者 Abani Pattanayak 《Journal of Computer and Communications》 2017年第8期62-68,共7页
Digital transformation has been corner stone of business innovation in the last decade, and these innovations have dramatically changed the definition and boundaries of enterprise business applications. Introduction o... Digital transformation has been corner stone of business innovation in the last decade, and these innovations have dramatically changed the definition and boundaries of enterprise business applications. Introduction of new products/ services, version management of existing products/ services, management of customer/partner connections, management of multi-channel service delivery (web, social media, web etc.), merger/acquisitions of new businesses and adoption of new innovations/technologies will drive data growth in business applications. These datasets exist in different sharing nothing business applications at different locations and in various forms. So, to make sense of this information and derive insight, it is essential to break the data silos, streamline data retrieval and simplify information access across the entire organization. The information access framework must support just-in-time processing capabilities to bring data from multiple sources, be fast and powerful enough to transform and process huge amounts of data quickly, and be agile enough to accommodate new data sources per user needs. This paper discusses the SAP HANA Smart Data Access data-virtualization technology to enable unified access to heterogenous data across the organization and analysis of huge volume of data in real-time using SAP HANA in-memory platform. 展开更多
关键词 SAP HANA In-Memory Computing SMART data Access (SDA) data virtualIZATION & data FEDERATION virtual data Model And Big data
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Automatic measurement of the working band of a digital attenuator based on virtual instrument
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作者 孙天锡 王亚军 《Journal of Measurement Science and Instrumentation》 CAS 2012年第1期18-21,共4页
To measure the working band of a digital attenuator automatically,a program based on virtual instrument was carried out,using Agilent E8362B network analyzer as its measuring tool.In the program,the attenuation values... To measure the working band of a digital attenuator automatically,a program based on virtual instrument was carried out,using Agilent E8362B network analyzer as its measuring tool.In the program,the attenuation values can be automatically written into Excel table to form the frequency-attenuation curve.Finally,through analyzing the attenuation in different frequency,the best working band of the digital attenuator can be determined easily,and the whole process is automated.Compared with the traditional way of changing the measured parameters manually and recording the measured data one by one,the developed method in the paper can avoid the cumbersome manual operation and its possible errors to improve the measurement accuracy and efficiency. 展开更多
关键词 microwave attenuator working band GPIB interface virtual instrument computer automation
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Reconstruction Model of Ocean Observing Complex Virtual Instrument
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作者 QIU Zhijin GUO Zhongwen +3 位作者 WANG Yu HU Tong LIU Chao LI Ting 《Journal of Ocean University of China》 SCIE CAS CSCD 2018年第5期1159-1170,共12页
With the newly proposed Global Ocean Observing Integration, ocean observing scope has been expanded from the region to the global, therefore the need of large-scale ocean observing system integration has become more a... With the newly proposed Global Ocean Observing Integration, ocean observing scope has been expanded from the region to the global, therefore the need of large-scale ocean observing system integration has become more and more urgent. Currently, ocean observing systems enabled ocean sensor networks are commonly developed by different organizations using specific technologies and platforms, which brings several challenges in ocean observing instrument (OOI) access and ocean observing system seamless integration. Furthermore, the development of ocean observing systems often suffers from low efficiency due to the complex prograrmning and debugging process. To solve these problems, a novel model, Complex Virtual Instrument (CVI) Model, is proposed. The model provides formal definitions on observing instrument description file, CVI description file, model calculation method, development model and interaction standard. In addition, this model establishes mathematical expressions of two model calculation operations, meanwhile builds the mapping relationship between observing instrument description file and CVI description file. The CVI based on the new model can achieve automatic access to different OOIs, seamless integration and communication for heterogeneous environments, and further implement standardized data access and management for the global unified ocean observing network. Throughout the development, integration and application of such CVI, the rationality and feasibility of the model have been evaluated. The results confirm that the proposed model can effectively implement heterogeneous system integration, improve development efficiency, make full usage of reusable components, reduce development cost, and enhance overall software system quality. We believe that our new model has great significance to promote the large-scale ocean observing system integration. 展开更多
关键词 ocean observing complex virtual instrument seamless integration model calculation development platform
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MEMS Test System Based on Virtual Instrument Technology
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作者 胡晓东 栗大超 +2 位作者 郭彤 胡春光 胡小唐 《Transactions of Tianjin University》 EI CAS 2007年第2期88-92,共5页
On account of the multiformity of MEMS devices, it is necessary to integrate with some optical measurement techniques for meeting static and dynamic unit test requirements. In this paper, an automated MEMS test system... On account of the multiformity of MEMS devices, it is necessary to integrate with some optical measurement techniques for meeting static and dynamic unit test requirements. In this paper, an automated MEMS test system is built of some commercially available components and instruments based on virtual instrument technology. The system is integrated with stroboscopic imaging, computer micro-vision, microscopic Mirau phase shifting interferometry, and laser Doppler vibrometer, and is used for the measurement of full-view in-plane and out-of-plane geometric parameters and periodical motions and single spot out-of-plane transient motion. The system configuration and measurement methods are analyzed, and some applications of the measurement of in-plane and out-of-plane dimensions and motions were described. The measurement accuracy of in-plane dimensions and out-of-plane dimensional is better than 0.2 um and 5 nm respectively. The resolution of measuring in-plane and out-of-plane motions is better than 15 nm and 2 nm respectively. 展开更多
关键词 MEMS optical measurement technique stroboscopic imaging virtual instrument dynamic test
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Ventilator performance evaluation system based on virtual instruments
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作者 戴文 任旭颖 林青 《Journal of Measurement Science and Instrumentation》 CAS 2012年第1期22-25,共4页
A virtual instrument system is proposed to test the performance parameters of local-ventilator installed under coal mines,which can do ventilator parameter acquisition automatically,as well as plot and analyze the ven... A virtual instrument system is proposed to test the performance parameters of local-ventilator installed under coal mines,which can do ventilator parameter acquisition automatically,as well as plot and analyze the ventilator performance curve.The whole system is designed using the virtual instrument technology combined with network technology based on Labview platform.Experimental results show that it can monitor and evaluate ventilator’s performance parameters automatically and efficiently,which provides critical information for ventilator safety under coal mine. 展开更多
关键词 virtual instrument ventilator performance evaluation remote transmission
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Parameter Test of ROIC for IRFPA Based on Virtual Instrument Technology
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作者 JIA Gong xian, YUAN Xiang hui, HUANG You shu, LU Guo lin (School of Photoelectric Eng., Chongqing University, Chongqing 400044, CHN) 《Semiconductor Photonics and Technology》 CAS 2001年第3期150-154,162,共6页
The readout integrated circuit (ROIC) technology is one of the critical technologies in the research of an infrared focal plane array (IRFPA). Based on the virtual instrument technology, a system for parameter test of... The readout integrated circuit (ROIC) technology is one of the critical technologies in the research of an infrared focal plane array (IRFPA). Based on the virtual instrument technology, a system for parameter test of ROIC is developed for IRFPA. The complex programmable logic device (CPLD) is applied into the system to increase its flexibility. With high reliability and precision, along with the integrated software and hardware environment, the system can test all kinds of ROICs. 展开更多
关键词 virtual instruments ROIC IRFPA CPLD
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The engine performance LabVIEW virtual instrument test system design
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作者 (Information and communication engineering institute,North university of China & National Key Laboratory For Electronic Measurement Technology Taiyuan,030051 China) Wang Xiao Han Yan(Institute of Computer Application,Shijiazhuang Railway Institute,Shijiazhuang,050043 China)Mao WanDui(UFIDA Software CO.LTD,Beijing,100085,China)Si Xiao-Hong 《微计算机信息》 北大核心 2008年第7期65-67,共3页
This paper adopts American National Instruments (NI) Company’s LabVIEW and LabVIEW RT virtual instrument softwareplatform and lots of things for this engine performance LabVIEW virtual instrument test system, such as... This paper adopts American National Instruments (NI) Company’s LabVIEW and LabVIEW RT virtual instrument softwareplatform and lots of things for this engine performance LabVIEW virtual instrument test system, such as the matched NI PCI dataCollection Card, NI SCXI signal-adjusting instrument and NI compact FieldPoint (cFP) distributed I/O real time system hardware.This system has realized multi performances’parallel test; and it can complete load, torsional moment, rotate speed, power, pressureand temperature’s real time monitoring automatically according to user’s setting; and finally through TCP/IP protocol it realizes testdata’s teleshare and telecontrol that user put on the test system. This system has such character as short development period, highuse efficiency and low cost, at the same time it has strong extensibility and reusability, so it has very high applied cost. 展开更多
关键词 engine performance LabVIEW virtual instrument test system
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Testing System Based on Virtual Instrument for Readout Circuit of Infrared Focal Plane Array
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作者 XUE Lian MENG Li-ya YUAN Xiang-hui 《Semiconductor Photonics and Technology》 CAS 2008年第2期102-106,114,共6页
Readout integrated circuit(ROIC) is one of the most important components for hybrid-integrated infrared focal plane array(IRFPA). And it should be tested to ensure the product yield before bonding. This paper presents... Readout integrated circuit(ROIC) is one of the most important components for hybrid-integrated infrared focal plane array(IRFPA). And it should be tested to ensure the product yield before bonding. This paper presents an on-wafer testing system based on Labview for ROIC of IRFPA. The quantitative measurement can be conducted after determining whether there is row crosstalk or not in this system. This low-cost system has the benefits of easy expansion, upgrading, and flexibility, and it has been employed in the testing of several kinds of IRFPA ROICs to measure the parameters of saturated output voltage, non-uniformity, dark noise and dynamic range, etc. 展开更多
关键词 virtual instrument infrared focal plane array ROIC TESTING
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Electric Parameter Measurement System Based on Virtual Instrument
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作者 戴文 林青 +1 位作者 魏淑艳 曹明革 《Journal of Measurement Science and Instrumentation》 CAS 2011年第1期9-12,共4页
In this paper, virtual instnnnent technology is applied in the development of an electric parameter measta'ement system for mobile power stations. Virtual inset technology is used to lmasure and analyze electric para... In this paper, virtual instnnnent technology is applied in the development of an electric parameter measta'ement system for mobile power stations. Virtual inset technology is used to lmasure and analyze electric parameters of mobile power stations. The whole measurement system is mmpmed of computer, data acquisition card and LabView virtual instnnnent platform. It can be used to monitor, record, and analyze electric parameters of sinusoidal alternating ciroait These parameters include voltage, effective value of ctaxent, phase differences, power, and etc. Experimental results show that this virtual measuring device satisfy the requirement of mobile power station montoring anti dynamic property analysis. Hardware and software design of the system will be discussed in detail. 展开更多
关键词 virtual inset electric parameter measnt data acquisition mobile power station
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基于Data Fabric的多模数据管理方法 被引量:2
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作者 郑新俊 田国良 黄飞虎 《华东师范大学学报(自然科学版)》 CAS CSCD 北大核心 2023年第5期164-181,共18页
随着政府和企业在信息化向数字化演进历程中信息化程度的加深,各类应用系统生成的数据日益多模化、多源化、海量化,这对数据管理造成了新的挑战.为了解决这些挑战,数据管理领域涌现出了许多新的技术和理念,其中Data Fabric (数据编织)... 随着政府和企业在信息化向数字化演进历程中信息化程度的加深,各类应用系统生成的数据日益多模化、多源化、海量化,这对数据管理造成了新的挑战.为了解决这些挑战,数据管理领域涌现出了许多新的技术和理念,其中Data Fabric (数据编织)便是一种新兴的数据管理技术和方法,它将分布式数据存储、处理和应用整合为一个整体,并提供了一套可视化的接口进行管理.本文首先分析了Data Fabric的技术架构、技术特点、技术价值和对多模数据进行管理与应用的完整流程.其次,提出了基于时序指标的多模多源数据的异常监测方法、基于日志数据的多模多源数据的异常监测方法,它们通过Data Fabric技术的使用,处理速度分别提高了33.3%和42.2%, F1-score分别提高12.2个和14.8个百分点,进一步说明了Data Fabric技术和本文新提出方法的高效性和应用价值. 展开更多
关键词 data Fabric 多模数据管理 数据虚拟化
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