• Journal of Power Electronics
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• v.12 no.5
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• pp.813-820
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• 2012

This paper presents the development of a software supported acquisition system for metrological verification and testing of the equipment for monitoring and analysis of the basic electrical power quality parameters. The described procedure consists of two functionally connected segments. The first segment involves generation of the reference three-phase voltage signals, including the possibility of simulation of the various power quality disturbances, typical for electrical power distribution networks. The second part of this procedure includes the real-time recording of power quality disturbances in three-phase distribution networks. The procedure is functionally supported by the virtual instrumentation concept, including a software application developed in LabVIEW environment and data acquisition boards NI 6713 and NI 9215A. The software support of this system performs graphical presentation of the previously generated and recorded signal waveforms. A number of the control functions and buttons, implemented on the virtual instrument front panels, are provided to adjust the basic signal acquisition, generation and recording parameters.

• Journal of the Korea Convergence Society
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• v.10 no.3
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• pp.31-37
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• 2019

In this paper, we propose an approach to get the requirement of drone acquisition for the efficient dronebot combat system using brute force algorithm. We define parameters, such as width, depth, and important surveillance area for the surveillance mission in the Army battalion and company units based on real military operation environment and brute force algorithm with 4 steps including first, next, valid, output is applied to get the requirement of drone acquisition and each drone's path planning using computer simulation. As a result, we could get the requirement of drone acquisition and each drone's path planning, the Army could utilize our proposed approach in the Army dronebot combat system. In the future research, we will study on the reliability of our proposed approach to get the requirement of drone acquisition for the efficient dronebot combat system.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2008.03a
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• pp.16-21
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• 2008

Aero-engine, as one kind of rotating machinery with complex structure and high rotating speed, has complicated vibration faults. Therefore, condition monitoring and fault diagnosis system is very important for airplane security. In this paper, a vibration data acquisition and intelligent fault diagnosis system is introduced. First, the vibration data acquisition part is described in detail. This part consists of hardware acquisition modules and software analysis modules which can realize real-time data acquisition and analysis, off-line data analysis, trend analysis, fault simulation and graphical result display. The acquisition vibration data are prepared for the following intelligent fault diagnosis. Secondly, two advanced artificial intelligent(AI) methods, mapping-based and rule-based, are discussed. One is artificial neural network(ANN) which is an ideal tool for aero-engine fault diagnosis and has strong ability to learn complex nonlinear functions. The other is data mining, another AI method, has advantages of discovering knowledge from massive data and automatically extracting diagnostic rules. Thirdly, lots of historical data are used for training the ANN and extracting rules by data mining. Then, real-time data are input into the trained ANN for mapping-based fault diagnosis. At the same time, extracted rules are revised by expert experience and used for rule-based fault diagnosis. From the results of the experiments, the conclusion is obvious that both the two AI methods are effective on aero-engine vibration fault diagnosis, while each of them has its individual quality. The whole system can be developed in local vibration monitoring and real-time fault diagnosis for aero-engine.

• Journal of the Korean Society of Systems Engineering
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• v.8 no.1
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• pp.77-82
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• 2012

In Weapons acquisition process, if the requirements are not clear, it leads to confusion and conflict in business. In the development of next-generation weapons, to define and derive requirements has to start from decision of operational concept. It is difficult task and has many uncertainties. This paper has goal about development of knowledge acquisition process that derive military operational scenario-based requirements acquisition process and framework that classify and save the derived requirements for next project. That framework can generate new class and category, also suggest that verification of requirements. It help to derive and manage the requirements, and make it easy to grasp the requirements. Accordingly, it can help make military requirement plan and weapon acquisition process.

• Journal of Korean Library and Information Science Society
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• v.14
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• pp.217-240
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• 1987

The purpose of this study is to analyse the current theses acquisition in university libraries and to suggest some useful findings for the more efficient acquisition of the theses. The results of the study can be summarized as follows (1) Depositary copies of each thesis in the libraries should be increased. (2) Under cooperative efforts, libraries must establish the exchange system of the theses by region or subject or characteristics of universities. (3) Each library should set up concrete selection criteria for the receiving of theses. (4) Development of purchase system would be necessary for economic and prompt acquisition of theses. (5) Theses should be microformed so as to save their storage space. (6) To give su n.0, pport to effective acquisition activity, various bibliographies about theses should be published.

• Journal of the Korean Institute of Telematics and Electronics A
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• v.33A no.5
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• pp.24-30
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• 1996

In this paper, we propose a fast code acquisition method that can reduce drastically the mean acquisition time of the direct sequence spread spectrum (DS-SS) system by using and integrated search and verification (ISV) scheme. The proposed method performs simultaneously the search and verification processes at every search cell, through storing sufficiently long signal samples enough to perform the verification process form the previously received samples. We analyze and acquisition performance in the case of Gaussian channel to evaluate theacquisition perfomrance of the proposed method. From the simple numericl analysis result, we have shown that the acquisition performance of the proposed method is better than that of the conventional serial search method, and the performance improvement becomes more prominent as the channel environment becomes degraded.

• Korean Journal of Geomatics
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• v.1 no.1
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• pp.85-93
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• 2001

Geospatial database, which is the basis for Geo-Spatial Information Systems, is produced by conventional mapping methods. Recently, with increased demand for digital forms of the geospatial database, studies are carried out to automate its production. The automated mapping system is composed of the image acquisition subsystem, positioning subsystem, point referencing subsystem and the visualization subsystem. The image acquisition subsystem is the most important part of the overall production line because it is the starting point and will affect all subsequent processes. This paper presents a software analysis and design of the image acquisition subsystem. The design was carried out using the Unified Modeling Language which is a modeling method used extensively in the software engineering field.

• Journal of the Korean Institute of Telematics and Electronics S
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• v.34S no.8
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• pp.10-19
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• 1997

In this paper, perfodrmance of matched-filter (MF) acquisition scheme is analyzed for a direct-sequence/code-division-multiple-access (DS/CDMA) system in a microcellular environment. Mean acquistion time is used as a performance measure. It is demonstrated that acquisition performance is enhanced using interference suppression filter in a Rician fading channel. To apply for multiuser environments, multiple access interference is considered in the performance analysis. From the numerical results, it is shown that mean acquistion time decreases with the increasing SNR/chip, and acquisition performance is improved as the number of taps of interference suppression filter. It is also shown that mean acquisition time increases with the number of users in the system, and acquistion performance is degraded as the icrease of narrowband interference bandwidth. The analysis in this paper can be applied to a DS/CDMA overlay environment.

• Proceedings of the Korea Committee for Ocean Resources and Engineering Conference
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• 2001.05a
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• pp.166-171
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• 2001

A digital seismic data acquisition and processing system using a PC has been developed in order to replace the analog data acquisition system of shallow marine seismic survey. An A/D converter that has 12bits of resolution and 225KHz of conversion rate was ued to acquire data, and a data acquisition software was developed as a Windows program which provides convenience of use. Raw data acquired at field has been saved to the hard-disk simultaneously. The signal to noise ratio, vertical and horizontal resolution could be improved by a digital data processing of the raw data. The digital processing of the raw data includss gain recovery, filtering, deconvolution, and muting. With the prediction deconvolution algorithm multiple reflections appearing on the shallow marine seismic section could be removed successfully.

• Journal of the Korea Society of Computer and Information
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• v.7 no.3
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• pp.128-134
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• 2002

In this paper, the performance on the PN code acquisition of DS/CDMA system was analyzed using the Nakagami-m probability density function considered fading environment. The equations on detection probability, $P_D$ and false alarm probability, $P_{FA}$, decision variables affecting the PN code acquisition time were derived and proved using simulation in order to analyze the performance. In conclusion, It was necessary increasing the gain of PLL for correcting phase errors and improving the acquisition performance of PN code in apply to the rake receiver.