• 대한전기학회:학술대회논문집
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• 대한전기학회 2002년도 하계학술대회 논문집 A
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• pp.163-165
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• 2002

In this paper a new numerical algorithm for fault distance calculation and arcing fault recognition based on one terminal data and derived in lime domain is presented. The algorithm is derived for the case of most frequent single-phase line to ground fault. The faulted phase voltage at the fault place is modeled as a serial connection of fault resistance and arc voltage. The fault distance and arc voltage amplitude are estimated using Least Error Squares Technique. The algorithm can be applied for distance protection, intelligent autoreclosure and for fault location. The results of algorithm tested through computer simulation are given.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2001년도 하계학술대회 논문집 A
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• pp.220-222
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• 2001

This paper represents impedance calculation of the distance relay using PSCAD/EMTDC software for transmission line involving the UPFC (Unified Power Flow Controller) device, which is the most vigorous component of FACTS. The presence of the UPFC significantly affects the line parameters of transmission system, which are also influenced by the distance relay setting. Moreover depending on the UPFC location and its parameters, zones of setting the distance relay will be changed. The presence of the UPFC in the fault loop affects both voltage and current seen by relay. Therefore, the distance relay should be taken into account the variable injected voltage of the UPFC.

• Advances in concrete construction
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• 제8권4호
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• pp.277-283
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• 2019

In evaluating explosion-protection capacity, safety distance is broadly accepted as the distance at which detonation of a given explosive causes acceptable structural damage. Safety distance can be calculated based on structural response under blast loading and damage criteria. For the applicability of the safety distance, the minimum required stand-off distance should be given when the explosive size is assumed. However, because of the nature of structures, structural details and material characteristics differ, which requires sensitivity analysis of the safety distance. This study examines the safety-distance sensitivity from structural and material property variations. For the safety-distance calculation, a blast analysis module based on the Kingery and Bulmash formula, a structural response module based on a Single Degree of Freedom model, and damage criteria based on a support rotation angle were prepared. Sensitivity analysis was conducted for the Reinforced Concrete one-way slab with different thicknesses, reinforcement ratios, reinforcement yield strengths, and concrete compressive strengths. It was shown that slab thickness has the most significant influence on both inertial force and flexure resistance, but the compressive strength of the concrete is not relevant.

• 한국정보통신학회논문지
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• 제17권2호
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• pp.473-480
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• 2013

본 논문은 개선된 삼변측량법을 이용하여 위치인지에 대한 정확도를 향상시킨 위치인지 알고리즘을 개발하였다. 개발한 위치인지 알고리즘은 첫째, 측정된 신호세기를 기반으로 노드와의 거리를 계산한다. 특정한 위치에 노드를 배치한 후 노드와의 거리 측정시 오차가 발생했다는 가정 하에 설계하였다. 노드(수신기, 중계기)들로 부터 거리데이터가 전송되면 구역에 따라 위치 계산에 쓰일 인접한 노드를 선택한다. 위치계산은 두 원을 그룹으로 생성한 후 두 교점을 이용해서 사각형 영역 안의 네점의 위치를 구한다. 둘째, 구역 필터링 알고리즘 적용하였다. 노드들이 구성하는 4개의 구역이 있다고 가정하고, 한 구역은 6개의 위치인지 좌표를 담당하게 하였다. RF의 특성상 실제 거리가 멀수록 신호세기에 의한 거리 오차는 커지게 되어있다. 이를 구역 필터링을 통하여 1차 필터링을 하고 2차적으로 개선된 알고리즘을 적용하여 위치인지 오차를 최소화하였다.

• Bulletin of the Korean Chemical Society
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• 제35권7호
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• pp.1944-1950
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• 2014

Employment of a time consuming, sophisticated calculation using the all-atom force field and generalized-Born implicit solvent model (GBIS) for refinement of NMR structures has become practical through advances in computational methods and capacities. GBIS refinement improves the qualities of the resulting NMR structures with reduced computational times. However, the contribution of GBIS to NMR structures has not been sufficiently studied in a quantitative way. In this paper, we report the effects of GBIS on the refined NMR structures of ubiquitin (UBQ) and GB1 with subsets of distance restraints derived from experimental data. Random omission prepared a series of distance restraints 0.05, 0.1, 0.3, 0.5, and 0.7 times smaller. For each number, we produced five different restraints for statistical analysis. We then recalculated the NMR structures using CYANA software, followed by GBIS refinements using the AMBER package. GBIS improved both the precision and accuracy of all the structures, but to varied levels. The degrees of improvement were significant when the input restraints were insufficient. In particular, GBIS enabled GB1 to form an accurate structure even with distance restraints of 5%, revealing that the root-mean-square deviation was less than 1 ${\AA}$ from the X-ray backbone structure. We also showed that the efficiency of searching the conformational space was more important for finding accurate structures with the calculation of UBQ with 5% distance restraints than the number of conformations generated. Our data will provide a meaningful guideline to judge and compare the structural improvements by GBIS.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2000년도 추계종합학술대회 논문집(4)
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• pp.255-258
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• 2000

This thesis shows controlling the mobile robot with distance information gotten with ultrasonic sensors, and analysis of captured image. The ultrasonic sensors supplies more accurate distance data in limited area but shows unstable data unlimited area while image data generally shows stable data, but this requires so much time because of amounts of calculation. So this thesis considers the merits of ultrasonic sensors and image to implement robot system .

• 한국융합학회논문지
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• 제4권3호
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• pp.35-41
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• 2013

Grouping problem with similarities between DNA sequences are studied. The similaritymeasure and the distance measure showed the complementary characteristics. Distance measure can be obtained by complementing similarity measure, and vice versa. Similarity measure is derived and proved. Usefulness of the proposed similarity measure is applied to grouping problem of 25 cockroach DNA sequences. By calculation of DNA similarity, 25 cockroaches are clustered by four groups, and the results are compared with the previous neighbor-joining method.

• Journal of applied mathematics & informatics
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• 제29권1_2호
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• pp.327-335
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• 2011

Explicit formulas are given for the first and second Zagreb index, degree-distance and Wiener-type invariants of splice and link of graphs. As a consequence, the first and second Zagreb coindex of these classes of composite graphs are also computed.

• International Journal of Fuzzy Logic and Intelligent Systems
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• 제15권1호
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• pp.20-26
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• 2015

It is very difficult to design an underwater communication system because of multipath, Doppler effects, noise, and attenuation. These factors lead to errors in the communication performance and maximum propagation distance. In this study, we calculate the distance that can be realized using the direct-sequence code division multiple access (DS-CDMA) technique with direct-sequence spread spectrum (DSSS) in an underwater communication system considering only the attenuation and noise. We also compare the estimated and calculated propagation distances obtained for several different scenarios.

• Journal of Electrical Engineering and Technology
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• 제3권3호
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• pp.346-353
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• 2008

This paper defines the concept of “protectability” for the performance evaluation of distance relay considering its sensitivity and selectivity. The paper starts from the probabilistic modeling of the errors, and based on this model, a detailed explanation of protectability calculation for each zone of the distance relay is presented. An effect of the Weighting Rate and the Measurement Deviation on the protectability evaluation is also given. By considering this effect, the optimization of relay setting can be realized. The proposed method is applied to a typical model system to show its effectiveness