• 제목/요약/키워드: Association

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Resource allocation algorithm for space-based LEO satellite network based on satellite association

  • Baochao Liu;Lina Wang
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • 제18권6호
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    • pp.1638-1658
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    • 2024
  • As a crucial development direction for the sixth generation of mobile communication networks (6G), Low Earth Orbit (LEO) satellite networks exhibit characteristics such as low latency, seamless coverage, and high bandwidth. However, the frequent changes in the topology of LEO satellite networks complicate communication between satellites, and satellite power resources are limited. To fully utilize resources on satellites, it is essential to determine the association between satellites before power allocation. To effectively address the satellite association problem in LEO satellite networks, this paper proposes a satellite association-based resource allocation algorithm. The algorithm comprehensively considers the throughput of the satellite network and the fairness associated with satellite correlation. It formulates an objective function with logarithmic utility by taking the logarithm and summing the satellite channel capacities. This aims to maximize the sum of logarithmic utility while promoting the selection of fewer associated satellites for forwarding satellites, thereby enhancing the fairness of satellite association. The problems of satellite association and power allocation are solved under constraints on resources and transmission rates, maximizing the logarithmic utility function. The paper employs an improved Kuhn-Munkres (KM) algorithm to solve the satellite association problem and determine the correlation between satellites. Based on the satellite association results, the paper uses the Lagrangian dual method to solve the power allocation problem. Simulation results demonstrate that the proposed algorithm enhances the fairness of satellite association, optimizes resource utilization, and effectively improves the throughput of LEO satellite networks.

소아외과의 지수 질환 - 대한소아외과학회 정회원을 대상으로 한 2000년도 전국 조사 - (Index Cases in Pediatric Surgery - a National Survey by the Korean Association of Pediatric Surgeons, 2000 -)

  • 이명덕;김상윤;김우기;김인구;김성철;김신곤;김재억;김재천;김현학;박귀원;박우현;서정민;송영택;오수명;유수영;이두선;이석구;이성철;정상영;정성은;정을삼;정풍만;조마해
    • Advances in pediatric surgery
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    • 제7권2호
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    • pp.147-156
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    • 2001
  • 대한소아외과학회의 연례 행사인 2000년도 주제토의를 소아외과의 지수 질환으로 정하여 1999년 말 현재 3년 이상의 진료 실적을 가진 대한소아외과학회 정회원 36명을 대상으로 미리 작성된 조사서에 의하여 2차례의 수술 증례 수 등록을 시행하였다. 대상 환자는 1997년부터 1999년 말까지 3년간 수술이 시행된 환자로 하였으며, 1차 조사에서 30명이 응답하였고, 미비점 보완을 위한 2차 조사에는 26명이 응답하여 이 성적을 요약하였다. 본 성적을 바탕으로 향 후 대한소아외과학회의 지수 질환 대상 목록표를 작성 제시하였으며, 이를 코드화 하고자 제안하였다.

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담도폐쇄증 -대한소아외과학회 회원 대상 전국 조사- (Biliary Atresia -A Survey by the Korean Association of Pediatric Surgeons in 2011-)

  • 오정탁;김대연;김성철;김인구;김해영;김현영;남소현;박귀원;박우현;박진영;서정민;이남혁;이명덕;이석구;이성철;정상영;정성은;정재희;최금자;최순옥;최승훈;최윤미;한석주;홍정
    • Advances in pediatric surgery
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    • 제19권1호
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    • pp.1-13
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    • 2013
  • The Korean Association of Pediatric Surgeons (KAPS) performed the second nationwide survey on biliary atresia in 2011. It was a follow-up study to the first survey, which was performed in 2001 for the retrospective analysis of biliary atresia between 1980 and 2000. In the second survey, the authors reviewed and analyzed the clinical data of patients who were treated for biliary atresia by the members of KAPS from 2001 to 2010. A total of 459 patients were registered. Among them, 435 patients primarily underwent the Kasai operation. The mean age of patients who underwent the Kasai operation was $66.2{\pm}28.7$ days, and 89.7% of those patients had type III biliary atresia. Only five patients (1.4%) had complications related to the Kasai operation. After the Kasai operation, 269 (61.8%) of the patients were re-admitted because of cholangitis (79.9%) and varices (20.4%). One hundred and fifty-nine (36.6%) of the patients who underwent the Kasai operation subsequently underwent liver transplantation. The most common cause of subsequent liver transplantation was persistent hyperbilirubinemia. The mean interval between the Kasai operation and liver transplantation was $1.1{\pm}1.3$ years. Overall the 10-year survival rate after the Kasai operation was 92.9% and the 10-year native liver survival rate was 59.8%. We had 23 patients for primary liver transplantation without the Kasai operation. The mean age patients who underwent primary liver transplantation was $8.6{\pm}2.9$ months. In summary, among the 458 Kasai-operation and liver-transplantation patients, 373 lived, 31 died, and 54 were unavailable for follow up. One-third of the patient who survived have had complications correlated with biliary atresia. In comparison with the first survey, this study showed a higher survival rate and a greater number of liver transplantation.

선천성 장폐쇄증 2차 조사 - 대한소아외과학회 회원을 주 대상으로 한 전국조사 - (Intestinal Atresia - The Second National Survey)

  • 김성철;김대연;김상윤;김인구;김인수;김재억;김재천;김현영;박귀원;박우현;박진영;서정민;설지영;오수명;오정탁;이남혁;이명덕;이석구;이성철;정상영;정성은;정연준;정풍만;최금자
    • Advances in pediatric surgery
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    • 제16권1호
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    • pp.1-10
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    • 2010
  • 본 조사는 2007년부터 2009년까지 3년간 본 학회 정회원들에 의하여 수술받은 장폐쇄증 환아를 대상으로 한 후향적 조사이다. 또한 본 학회에서는 1994년부터 1996년까지 3년간의 증례를 대상으로 같은 조사(1 차조사)를 진행한 바 있다. 1 차 조사와 비교하여 본 조사에서 보이는 특징은 아래와 같이 요약할 수 있다. - 총 증례 수는 비슷하였으나 출생률을 감안하여야 할 것이다. - 각 기형별 비율은 비슷하였다. - 미숙아 및 저출생체중아의 비율은 증가 하였다. - 산전진단율은 증가하였다. - 복부단순촬영만 한 경우는 감소하였다. - 다른 기형이 동반된 예가 증가하였다. - 사망률이 13.8 %에서 3.6 %로 감소하였다. 장운동의 회복은 공장폐쇄증에서 십이지장이나 회장폐쇄증에서 보다 더뎠다. 하지만 십이지장-공장 이행부에서 문합부까지의 거리가 기술되지 않은 예가 많아 소위 "High Jejunal obstruction"에서의 장운동 회복기간을 알아 보지 못 하는 아쉬움이 있었다. 또한 주름형성술(plication) 또는 장의 직경을 줄이는 수술(tapering)의 효과도 시행한 예수가 작고, 문합부 위치의 기술 부족으로 알아 보지 못 하였다. 십이지장폐쇄증의 화타씨유두부와 위치 역시 향후 보다 정확한 수술기록을 토대로 조사되어야 할 것으로 생각된다. 치료 성적의 눈부신 향상은 여러 회원들의 각고의 노력과 의학의 발달에 기인한 것으로, 사망률 0 %를 향한 노력이 지속되어야 할 것이다.

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Recently Trend of Korean Study in the Field of Climatology and Environmental Geography in the Association of Japanese Geographer

  • 박혜숙
    • 대한지리학회:학술대회논문집
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    • 대한지리학회 2002년도 추계학술대회 요약집
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    • pp.9-18
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    • 2002
  • I. Trend of the Association of Japanese Geographers in 1970-1980. II. Reformation of the Association of Japanese Geographers Since 1980. III. Changing Era Revolution of Universities. IV. Geographical Education in the Association of Japanese Geographers. V. Overseas field WOrs in the Association of Japanese Geographers. VI. Recently Trend of Korean Study in the Field of Climatology and Environmental Geography in the Association of Japanese Geographers.

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시론 - 대한치과의사협회의 금연활동 (No Smoking Activities of Korean Dental Association)

  • 김경선
    • 대한치과의사협회지
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    • 제48권5호
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    • pp.342-348
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    • 2010
  • Korean dental association (KDA) intensively drives no smoking activities for a healthy life of Korean people. In this article, hazardous facts of smoking in oral system are reviewed from the point of view of dental science. Various activities against smoking including campaigns, conferences, polls, exhibitions and publications driven by KDA are introduced.

Statistical Decision making of Association Threshold in Association Rule Data Mining

  • 박희창;송금민
    • Journal of the Korean Data and Information Science Society
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    • 제13권2호
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    • pp.115-128
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    • 2002
  • One of the well-studied problems in data mining is the search for association rules. In this paper we consider the statistical decision making of association threshold in association rule. A chi-squared statistic is used to find minimum association threshold. We calculate the range of the value that two item sets are occurred simultaneously, and find the minimum confidence threshold values.

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Statistical Decision making of Association Threshold in Association Rule Data Mining

  • Park, Hee-Chang;Song, Geum-Min
    • 한국데이터정보과학회:학술대회논문집
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    • 한국데이터정보과학회 2002년도 춘계학술대회
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    • pp.169-182
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    • 2002
  • One of the well-studied problems in data mining is the search for association rules. In this paper we consider the statistical decision making of association threshold in association rule. A chi-squared statistic is used to find minimum association threshold. We can calculate the range of the value that two item sets are occurred simultaneously, and can find the minimum confidence threshold values.

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A Systematic and Efficient Approach for Data Association in Topological Maps for Mobile Robot using Wavelet Transformation

  • Doh, N.L.;Lee, K.;Chung, W.K.
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 2004년도 ICCAS
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    • pp.2017-2022
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    • 2004
  • Data association is a process that matches a recent observation with known data set, which is used for the localization of mobile robots. Edges in topological maps have rich information which can be used for the data association. However, no systematic approach on using the edge data for data association has been reported. This paper proposes a systematic way of utilizing the edge data for data association. First, we explain a Local Generalized Voronoi Angle(LGA) to represent the edge data in 1-dimension. Second, we suggest a key factor extraction procedure from the LGA to reduce the number by $2^7-2^8$ times, for computational efficiency using the wavelet transformation. Finally we propose a way of data association using the key factors of the LGA. Simulations show that the proposed data association algorithm yields higher probability for similar edges in computationally efficient manner.

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