• Proceedings of the IEEK Conference
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• 2000.06a
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• pp.252-255
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• 2000

In this paper, a fast pseudo-noise (PN) code acquisition with novel adaptive architecture is presented in direct-sequence spread- spectrum (DS-SS) systems. Since an existing acquisition system has a fixed correlation tap size and threshold value, this system cannot adapt to various mobile communication environments and results in a low detection probability or a high false alarm rate and long acquisition time. Therefore, if a correlation tap size and a threshold value can be controlled adaptively according to received signals, problems of ail existing system will be solved. The system parameter varies adaptively by using constant false alarm rate (CFAR) algorithm well known in a field of detection and proposed signal-to-noise ratio (SNR) measurement system. By deriving formulas of the proposed system, the performance is analyzed.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.21 no.5
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• pp.1230-1239
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• 1996

This paper analyzes matched-filter acquistion performance of a direct-sequence spread-specturm multiple-access system in a Rayleigh fading channel. For an application of multiple access system, multiple access interference is considered in the performance analysis. A signal flow graph technique is used to derive mean acquisition time in terms of detection and false alarm probabilities. As aresult of performance analysis, it is shown that mean acquisition time increases as fading rate becomes faster andthe numbre of users increases, and it decreases as a matched-filter length becomes logner. The variation of parameter values hs much influence on acquisition performance as SNR/chip becomes smaller.

• Journal of Astronomy and Space Sciences
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• v.28 no.4
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• pp.345-354
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• 2011

Earth acquisition is to solve when earth can be visible from satellite after Sun acquisition during launch and early operation period or on-station satellite anomaly. In this paper, the algorithm and test result of the Communication, Ocean and Meteorological Satellite (COMS) Earth acquisition are presented in case of on-station satellite anomaly status. The algorithms for the calculation of Earth-pointing attitude control parameters including those attitude direction vector, rotation matrix, and maneuver time and duration are based on COMS configuration (Eurostar 3000 bus). The coordinate system uses the reference initial frame. The constraint calculating available time-slot to perform the earth acquisition considers eclipse, angular separation, solar local time, and infra-red earth sensor blinding conditions. The results of Electronics and Telecommunications Research Institute (ETRI) are compared with that of the Astrium software to validate the implemented ETRI software.

• Proceedings of the Korean Nuclear Society Conference
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• 1998.10a
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• pp.73-73
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• 1998

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.11 no.5
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• pp.151-157
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• 2011

This study analyzed the posture balance of time variation for exercising body a period of time. Posture balance measured output values for the posture balance system of body moving in the multi-parameter. Posture moving variation had three methods such as open and closed eye, head moving and upper body moving. There were checked a parameter that measured vision, vestibular, somatosensory, CNS. This system was evaluated a data through the stability. This system has catched a signal for physical condition of body data such as a data acquisition system, data signal processing and feedback system. The output signal was generated Fourier analysis that using frequency of 0.1Hz, 0.1-0.5Hz, 0.5-1Hz and 1Hz over. The posture balance system will be used to support assessment for body moving the posture balance of time variation. It was expected to monitor a physical parameter for health verification system.

• Journal of Aerospace System Engineering
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• v.11 no.2
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• pp.1-8
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• 2017

Delivering clear requirements of the military in the defense acquisition process is a key activity for successful weapon acquisition. In the field of defense, Operational Requirements Documents (ORDs) are prepared to derive and deliver the requirements of the military. In this study, we compare and analyze the form and content of the recent domestic ORD with reference to the US Department of Defense (DoD) ORD. As a result of the study, it is found that the domestic ORD form needs to be supplemented with in accordance with the purpose of the operation, while the requirement parameter, which is a core item of ORD, is insufficient. In order to address these issues, detailed contents of the ORD form suitable for the purpose of this study are presented. Also, we provide clear definitions, explanations, and examples of the operational system's key performance parameters and suggest ways to clearly communicate the requirements of the military.

• Proceedings of the Korean Association of Geographic Inforamtion Studies Conference
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• 2008.06a
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• pp.310-317
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• 2008

Although aerial LiDAR had been launched commercially several years ago, it is still difficult to study data acquisition conditions and effects with various datasets because of its acquisition cost. Thus, this research was performed to study data acquisition conditions and effects with virtually various datasets. For this research, 3D tree models and forest stand models were built to represent graded tree sizes and tree plantation densities. Also, a variable aerial LiDAR acquisition model was developed. Then, through controlling flight height parameter, one of the data acquisition parameters, virtual datasets were collected for various data acquisition densities. From those datasets, forest canopy volumes and maximum tree heights were estimated and the estimated results were compared. As the results, the estimated is getting closer to the expected during the data acquisition density increase. This research would be helpful to perform further studios on relations between forest inventory accuracy and LiDAR cost.

• Annual Conference on Human and Language Technology
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• 1989.10a
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• pp.296-301
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• 1989

본 논문의 목적은 매개변항(parameter)과 부분집합원리(subset principle)를 재귀대명사 구조분석 및 습득에 적용하여 보편문법(Universal Grammar)과 언어습득의 상호관계를 검토하는 데에 있다. 본 논문은 첫째, 재귀대명사 '자기'를 매개변항이론에 근거하여 분석하고, 둘째, 재귀사의 구조를 부분집합원리에 적용하여 '자기'의 습득과정을 관찰한다. 본 논문의 목적을 위해 두 가지 가설을 세워 실험적으로 검증하였다. 실험결과, 선행사자격 습득단계의 가설이 확증되었으며, 지배변항 습득단계의 가설은 결정적 증거가 미비해 앞으로의 과제로 남아 있다.

• The Korean Journal of Nuclear Medicine
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• v.38 no.6
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• pp.540-542
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• 2004

Although artifacts in tomographic imaging can arise from a number of sources, this case presents an artifact caused by using inadequate acquisition parameters which do not match the collimator with which a camera equipped in Tc-99m ECD brain SPECT. Whenever the collimator in tomographic studies is changed, we should take care to use suitable parameters of acquisition protocol according to the collimator with which a camera is fitted. Other ways to prevent an error of this type is to use a point source.

• Journal of Information Processing Systems
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• v.16 no.2
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• pp.394-405
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• 2020

The parameters of transmission lines have an influence on the electromagnetic environment surrounding the line. This paper proposes a method based on phasor measurement unit (PMU) and supervisory control and data acquisition (SCADA) to achieve online estimation of transmission line full parameters, such as resistance, reactance and susceptance. The proposed full parameter estimation method is compared with the traditional method of estimating resistance independently based on SCADA system. Then, the electromagnetic environment is analyzed based on the different parameter estimation methods. The example results illustrate that online estimation of transmission line full parameters is more accurate in the analysis of electromagnetic environment, which further confirms its necessity and significance in engineering application.