• 방송공학회논문지
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• 제18권1호
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• pp.59-65
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• 2013

최근 지상파 방송은 아날로그 TV방송에서 디지털 TV방송으로의 전환이 진행 중에 있다. 이러한 디지털 TV방송 전환 이후에 동일 채널 간섭으로 인한 TV White space (TVWS)의 재할당 및 배치가 필요하다. 본 논문에서는 방송서비스 전파모델로 가장 많이 사용되고 있는 Longley-Rice와 ITU-R P.1546 전파모델에서 동일채널간섭 (CCI; co-channel interference)으로 인해 발생되는 TVWS에 대해 연구한다. 또한 디지털 방송에서 송신 안테나 높이와 송신전력에 따른 서비스 커버리지 반경과 CCI 반경을 분석한다. 분석결과에 의하면, Longley-Rice와 ITU-R P.1546 전파모델의 평균적인 CCI 반경 대 서비스 커버리지 반경의 비는 각각 2.54, 2.07이었다.

• 한국정보통신학회논문지
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• 제18권7호
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• pp.1547-1556
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• 2014

본 논문에서는 인접성(Proximity)과 적시성(Timeliness)의 특징을 가지고 있는 D2D 통신과 소셜 커머스 서비스가 결합된 저비용/고효율의 소셜 커머스 서비스 기반 D2D 광고 시나리오를 제안하고, D2D 통신과 소셜 커머스 서비스의 결합을 통한 광고 효과를 알아보기 위하여, 섹터의 수에 따른 광고 확산 효과(Advertisement Dissemination Effect)를 수학적으로 분석해 본다. 또한, 시뮬레이션을 통하여 정규 D2D 커버리지(Normalized D2D Coverage), 유효 범위내 광고 전달을 위한 평균 Relay 단말 수, 단위 전송 단말 당 평균 D2D 커버리지에 대해 살펴보고, 수학적 분석 결과와 시뮬레이션 결과를 비교함으로써 D2D 광고 커버리지에 대한 수학적 분석의 정확성을 알아본다.

• 보건행정학회지
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• 제31권3호
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• pp.344-354
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• 2021

Background: The purpose of this study was to analyze the effect of national health insurance coverage of Chuna therapy in April 2019 on the costs and service uses in automobile insurance. Methods: This study used the claim data from Health Insurance Review and Assessment Service. A total of 189,912 inpatients and 1,550,497 outpatients who received Chuna therapy covered by automobile insurance in oriental medical institutions were included. The analysis period was from July 2018 to December 2019, and a total of 18 months before and after April 2019, when Chuna therapy was covered by national health insurance. Interrupted time series analysis was applied to analyze the impact on the costs and service uses of Chuna therapy in automobile insurance before and after April 2019. Results: From July 2018 to December 2019, for 189,912 inpatients the cost and the number of times for Chuna therapy per capita were increased by 22.0% and decreased by 7.3% respectively right after the implementation of the policy. In the case of 1,550,497 outpatients, the cost of Chuna therapy per capita tends to be increased by 0.4% in overall study periods and increased 28.4% immediately after the implementation of the policy. Meanwhile, the number of times and visits for Chuna therapy per capita tends to be increased by 0.4% in overall study periods but decreased by 0.4% after the implementation of the policy. Conclusion: Results suggest that if the national health insurance coverage of oriental medicine services increases according to the policy stance for benefit expansion in national health insurance, the criteria for providing national health insurance benefits should be considered with the comprehensive impacts on the costs and service uses of automobile insurance.

• 한국경영과학회:학술대회논문집
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• 한국경영과학회 2007년도 추계학술대회 및 정기총회
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• pp.316-321
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• 2007

The hierarchical covering location problem emphasizes the issue of locating of hierarchical facilities in order to maximize the number of customers that can be covered. In the classical HCLP(Hierarchical Covering Location Problem), it is assumed that the customers are covered completely if they are located within a specific distance from the facility, and not covered otherwise. The generalized HCLP is introduced that the coverage of customers is measured to be any real value rather than 0 or 1, where the service level may decrease according to the distance. Mixed integer programming formulation for the generalized HCLP is suggested with a partial coverage of service. Solutions are found using OPL Studio, and are evaluated for various cases.

• 한국항해항만학회:학술대회논문집
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• 한국항해항만학회 2001년도 Proceeding of KIN-CIN Joint Symposium 2001 on Satellite Navigation/AIS, lntelligence , Computer Based Marine Simulation System and VDR
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• pp.6-12
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• 2001

Korea government decided to provide the NDGSP service and the conceptional design report are presented here. The coverage of the exiting MDGPS stations of inland area is measured and the positions and characteristics of additional inland NDGPS sites are proposed for the full-coverage of inland areas of Korea.

• 한국항해항만학회:학술대회논문집
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• 한국항해항만학회 2001년도 Proceeding of KIN-CIN Joint Symposium 2001 on Satellite Navigation/AIS, lntelligence , Computer Based Marine Simulation System and VDR
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• pp.7-12
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• 2001

Korea government decided to provide the NDGSP service and the conceptional design report are presented here. The coverage of the exiting MDGPS stations of inland area is measured and the positions and characteristics of additional inland NDGPS sites are proposed for the full-coverage of inland areas of Korea.

• Korean Journal of Radiology
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• 제25권6호
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• pp.508-510
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• 2024

• 한국정보통신학회논문지
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• 제15권10호
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• pp.2059-2064
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• 2011

우리나라는 GPS 보정시스템인 DGPS 위성항법보정시스템이 해안용 11곳과 내륙용 6곳의 기준국이 설치 되어 운용되고 있다. 내륙 기준국은 위성항법 보정신호를 500W 출력으로 서비스하고 있으나, 산간 지역 등 국내 지역에 따라 음영지역이 발생한다. 본 논문에서는 내륙 기준국의 출력을 1kW 이내에서 증강할 경우, 내륙 기준국별 서비스 영역을 해석하고, 6곳의 내륙 기준국과 11곳의 해안 기준국과의 이중 서비스 영역을 고려하여 국내 내륙지역의 DGPS 서비스 음영지역을 분석한다. DGPS 전파 모델로는 중파 대역 전파 모델을 사용하고, 내륙 지역의 도전율은 보정된 지표 도전율을 적용하여 출력에 따른 서비스 영역을 해석한다.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2005년도 춘계학술대회 논문집
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• pp.1468-1471
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• 2005

This Paper is to find out a solution for the full-coverage algorithm requiring the real-time processing such as mobile home service robots and vacuum cleaner robots. Previous methods are used by adopting based grid approach method. They used lots of sensors, a high speed CPU, expensive ranger sensors and huge memory. Besides, most full-coverage algorithms should have a map before obstacle avoidance. However, if a robot able to recognize the tangent vector of obstacles, it is able to bring the same result with less sensors and simplified hardware. Therefore, this study suggests a topological based approach and a local obstacle voidance method using a few of PSD sensors and ultra sonic sensors. The simulation results are presented to prove its applicability.

• 한국항공운항학회지
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• 제22권3호
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• pp.74-81
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• 2014

The coverage area of GNSS regional ionospheric correction model is mainly determined by the disribution of GNSS ground monitoring stations. Outside the coverage area, GNSS users may receive ionospheric correction signals but the correction does not contain valid correction information. Extrapolation of the correction information can extend the coverage area to some extent. Three interpolation methods, Kriging, biharmonic spline and cubic spline, are tested to evaluate the extrapolation accuracy of the ionospheric delay corrections outside the correction coverage area. IGS (International GNSS Service) ionosphere map data is used to simulate the corrections and to compute the extrapolation error statistics. Among the three methods, biharmonic method yields the best accuracy. The estimation error has a high value during Spring and Fall. The error has a high value in South and East sides and has a low value in North side.