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네트워크 분석기법을 이용한 광역도시권 설정방안 - 부산광역권 설정사례를 중심으로 - (The Boundary Delimitation of Busan Metropolitan Area using Network Analysis)

  • 심재헌;조연호
    • Spatial Information Research
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    • 제19권6호
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    • pp.75-86
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    • 2011
  • 본 연구는 부산권을 사례대상으로 하여 보완된 광역도시권 설정방안을 제시하고 실증적인 설정결과를 현행 광역도시권 설정사례와 비교하였다. 분석의 공간적 대상선정과 관련해서는 네트워크 분석 기법의 하나인 서비스 권역 분석을 통하여 중심도시의 반경권이 아닌 광역교통망의 실제 분포를 반영하였으며, 중심도시와 주변지역 간의 연계성 분석은 기종점 통행량 자료를 사용하여 통근 통학과 더불어 업무 구매 여가 친교 등의 다양한 통행행위를 고려하였다. 또한 주변지역의 도시적 특성은 지표항목을 추가적으로 적용하고, 분석과정에서 토지피복지도를 사용하여 분석의 정확도를 높이고자 하였다. 본 연구에서 설정한 광역도시권의 설정범위는 현행 광역도시권 설정사례와 비교하여 일부지역에서 차이를 나타내며, 이는 인접한 지역 간에 새롭게 형성된 동질적 생활권의 양상이 반영된 점에 따른 것으로 사료된다.

Neighborhood coreness algorithm for identifying a set of influential spreaders in complex networks

  • YANG, Xiong;HUANG, De-Cai;ZHANG, Zi-Ke
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • 제11권6호
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    • pp.2979-2995
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    • 2017
  • In recent years, there has been an increasing number of studies focused on identifying a set of spreaders to maximize the influence of spreading in complex networks. Although the k-core decomposition can effectively identify the single most influential spreader, selecting a group of nodes that has the largest k-core value as the seeds cannot increase the performance of the influence maximization because the propagation sphere of this group of nodes is overlapped. To overcome this limitation, we propose a neighborhood coreness cover and discount heuristic algorithm named "NCCDH" to identify a set of influential and decentralized seeds. Using this method, a node in the high-order shell with the largest neighborhood coreness and an uncovered status will be selected as the seed in each turn. In addition, the neighbors within the same shell layer of this seed will be covered, and the neighborhood coreness of the neighbors outside the shell layer will be discounted in the subsequent round. The experimental results show that with increases in the spreading probability, the NCCDH outperforms other algorithms in terms of the affected scale and spreading speed under the Susceptible-Infected-Recovered (SIR) and Susceptible-Infected (SI) models. Furthermore, this approach has a superior running time.

Variation in Solar Limb Darkening Coefficient Estimated from Solar Images Taken by SOHO and SDO

  • Moon, Byeongha;Jeong, Dong-Gwon;Oh, Suyeon;Sohn, Jongdae
    • Journal of Astronomy and Space Sciences
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    • 제34권2호
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    • pp.99-103
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    • 2017
  • The sun is not equally bright over the whole sphere, but rather is darkened toward the limb. This effect is well-known as limb darkening. The limb darkening coefficient is defined by the ratio of the center intensity to limb intensity. In this study, we calculate the limb darkening coefficient using the photospheric intensity estimated from solar images taken by solar and helispheric observatory (SOHO) and solar dynamics observatory (SDO). The photospheric intensity data cover almost two solar cycles from May 1996 to December 2016. The limb darkening coefficient for a size of 0.9 diameter is about 0.69 and this value is consistent with solar limb darkening. The limb darkening coefficient estimated from SOHO shows a temporal increase at solar maximum and a gradual increase since the solar minimum of 2008. The limb darkening coefficient estimated from SDO shows a constant value of about 0.65 and a decreasing trend since 2014. The increase in the coefficient reflects the effect of weakened solar activity. However, the decrease since 2014 is caused by the aging effect.

Geometric Optimization of a Mathematical Model of Radiofrequency Ablation in Hepatic Carcinoma

  • Wang, Kai-Feng;Pan, Wei;Wang, Fei;Wang, Gao-Feng;Madhava, Pai;Pan, Hong-Ming;Kong, De-Xing;Liu, Xiang-Guan
    • Asian Pacific Journal of Cancer Prevention
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    • 제14권10호
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    • pp.6151-6158
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    • 2013
  • Radio frequency ablation (RFA) is an effective means of achieving local control of liver cancer. It is a particularly suitable mode of therapy for small and favorably located tumors. However, local progression rates are substantially higher for large tumors (>3.0 cm). In the current study, we report on a mathematical model based on geometric optimization to treat large liver tumors. A database of mathematical models relevant to the configuration of liver cancer was also established. The specific placement of electrodes and the frequency of ablation were also optimized. In addition, three types of liver cancer lesion were simulated by computer guidance incorporating mathematical models. This approach can be expected to provide a more effective and rationale mechanism for employing RFA in the therapy of hepatic carcinoma.

경관지수와 생태계용역가치를 활용한 대구광역도시권 경관의 구조적·기능적 변화 분석 (The Structural and Functional Analysis of Landscape Changes in Daegu Metropolitan Sphere using Landscape Indices & Ecosystem Service Value)

  • 최원영;정성관;오정학;유주한
    • 한국지리정보학회지
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    • 제8권4호
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    • pp.102-113
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    • 2005
  • 생태계는 인간, 생물 무생물적 환경의 집합체이며, 경관은 생태계가 단위지역에 나타나는 현상이다. 이러한 경관은 다양한 경관요소가 시 공간적으로 나타나는 토지 모자이크이며, 토지이용과 피복 변화는 경관의 구조를 변화시키는 주요 요인이다. 본 연구에서는 경관을 구조적 기능적 측면에서 정량화하는 경관지수와 생태계용역가치(Ecosystem Service Value: ESV)를 이용하여 대구광역도시권의 산림경관의 시 공간적 변화패턴에 관하여 분석하였다. 분석결과, 산림경관의 잠식과 파편화는 택지 및 공업단지조성 등의 대규모 개발행위 보다는 도로 등의 선형적 개발에 의해 발생되었으며, 핵심지역의 상대적 비율은 점진적으로 감소한 것으로 나타났다. 이러한 현상은 생물종의 주요 서식처가 되는 핵심지역을 감소시켜 그 건전성을 저하시킬 가능성이 있을 것으로 판단되었다. 또한 ESV가 산림경관의 면적변화와 밀접한 관계를 가지는 것을 알 수 있었다. 이러한 연구결과들은 향후 생태계를 대상으로 한 개발과 보존의 논리 사이에서 객관적인 평가의 기틀을 마련하고, 광역도시계획 등의 개발계획 수립에서 생태계 가치를 충분히 반영하기 위한 기본적인 척도로 활용 가능할 것이다.

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Crimean Citizen Journalism: Genesis and Trends in Communication Network

  • Iuksel, Gaiana Z.;Sydorenko, Natalііa M.;Dosenko, Anzhelika K.;Sytnyk, Oleksii V.;Dubetska, Oksana O.
    • International Journal of Computer Science & Network Security
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    • 제22권2호
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    • pp.63-74
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    • 2022
  • Repressive measures in the Crimea against the Ukrainian media and the ban on the entry of international and Ukrainian monitoring missions created the conditions for the function of providing information to be performed by representatives of civil society. Such a phenomenon was called Crimean citizen journalism and became a post-occupation phenomenon characteristic of the Crimean information sphere. The journalists' activities are aimed at reporting on human rights violations and repression against Ukrainian citizens who find themselves in conditions of information bans and restrictions. Crimean citizen journalism, which connects the peninsula with the mainland of Ukraine, is monothematic in nature, and its emergence has become a form of nonviolent resistance to the occupation of Crimea. The purpose of the study is to cover the characteristic features, the development of common Crimean citizen journalistic movement features as a social phenomenon, a phenomenon that arose after the occupation through the identification of a modern journalist portrait. The study uses the general scientific method of empirical research as the main one, the sociological method of a questionnaire survey, as well as the methods of classification, generalisation, observation, statistical calculation. An analysis of a survey of Crimean citizen journalists demonstrates the existence of an active, mobile community in Crimea that seeks to provide information and human rights nonviolent resistance to the occupation.

SPECT/CT에서 인공고관절에 대한 감쇠보정지도(Attenuation Map)의 매개변수 변화에 따른 금속 인공물(Metal Artifact)의 영향 평가 (Evaluation of the Effect of Metal Artifacts Varying the Parameters of the Attenuation Map for the artificial Hip Joint in SPECT/CT)

  • 김상규;김정열;박민수;조승현;임한상;김재삼
    • 핵의학기술
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    • 제18권2호
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    • pp.3-7
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    • 2014
  • CT를 기반으로 감쇠보정이 시행되는 SPECT/CT 검사에서는 금속 삽입물에 의한 선속경화현상으로 인접한 부위의 과대평가를 유발하며, 영상의 질을 저하시킨다. 이에 대해, 본 연구에서는 인공고관절이 삽입된 팬텀을 이용하여 감쇠보정지도의 매개변수 변화에 따른 금속 인공물이 SPECT/CT 영상에 미치는 영향을 알아보고자 한다. SPECT/CT 장비는 Siemens사의 Symbia T16을 사용하였다. SPECT/PET 팬텀에 인공고관절을 삽입하고, CT영상에서 Bright Streak 영역에 직경 17 mm의 구를 배후방사능 대비 8배가 되도록 Tc-99m을 채웠다. 이후 감쇠보정지도에서 Wide Beam Coefficient[수동모드(0.1~0.9), 자동모드]변화에 따른 열소와 배후방사능의 계수를 측정하였고, 고관절의 유무에 따라 Metal과 Non-Metal의 병소 대 배후방사능 비(Region to Background Ratio, RBR)를 산출 및 비교 분석하였다. 수동모드의 값이 증가할수록 Metal과 Non-Metal의 열소 계수는 증가하는 경향을 나타냈으며, 수동모드 0.4와 0.5에서 두 군과의 열소 계수비가 가장 일치하게 나타났다(수동모드 0.4=1.001, 0.5=0.999). 또한 $RBR^{Metal}$$RBR^{Non-Metal}$의 비는 자동모드에서 1.135이였고, 수동모드 0.4와 0.5에서 통계적으로 유의한 차이를 보이지 않았다(0.4=0.999, 0.5=1.028, p=0.78). 감쇠보정지도에서 Wide Beam Coefficient의 자동모드는 13.52% 과 보정 되는 것을 알 수 있었으며, 수동모드 중 0.4와 0.5에서 인공물에 의한 과 보정을 최소화 할 수 있었다. 이를 활용하여 환자에게 적용하기 위해서는 추가적인 연구가 이루어져야 할 것이며, 고관절전치환술 환자의 인공고관절 주변에서 금속 인공물에 의한 과 보정을 감소시켜 진단능을 향상시킬 수 있을 것으로 사료된다.

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국제상사조정 및 중재제도 개선에 관한 UNCITRAL 논의동향 (Discussion by UNCITRAL for Development of International Commercial Conciliation and Arbitration Systems)

  • 이강빈
    • 한국중재학회지:중재연구
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    • 제10권1호
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    • pp.3-25
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    • 2000
  • At its thirty-second session in 1999, the UNCITRAL had before it the requested note entitled "Possible future work in the area of international commercial arbitration." After concluding the discussion on its future work in the area of international commercial arbitration, it was agreed that the priority items for the working group should be conciliation, requirement of written form for the arbitration and enforceability of interim measures of protection. the Commission entrusted the work to the Working Group on Arbitration which held its thirty-second session at Vienna from 20 to 31 March 2000. The Working Group discussed agenda item 3 on the basis of the report of Secretary General entitled "Possible uniform rules on certain issues concerning settlement of commercial disputes : conciliation, interim measures of protection, written form for arbitration agreement." At its thirty-three session in 2000, the UNCITRAL had before it the report of Secretary General on agenda item 3 discussed by the Working Group. The Working Group discussed the issues relating to certain aspects of conciliation proceedings ; (1) Admissibility of certain evidence in subsequent judicial or arbitral proceedings ; (2) Role of conciliatior in arbitration or court proceedings ; (3) Enforceability of settlement agreements reached in conciliation proceedings ; (4) Other possible items for harmonized treatment : a) Admissibility or desirability of conciliation by arbitrators b) Effect of an agreement to conciliate on judicial or arbitral proceedings c) Effect of conciliation on the running of limitation period d) Communication between the conciliator and parties ; disclosure of information e) Role of conciliator. It was generally considered that decisions as to the form of the text to be prepared should be made at a later stage when the substance of prepared solutions would become clearer. However, it was noted that model legislative provisions seemed to be appropriate form for a number of matters proposed to be discussed in the area conciliation. There was general support in the Working Group for the proposition to perpare a legislative regime governing the enforcement of interim measures of protection ordered by arbitral tribunals. It was generally considered that legislative regime should apply to enforcement of interim measures issued in arbitration taking place in State where enforcement was sought as well as outside that State. It was generally observed that there was a need for provisions which conformed to current practice in international trade with regard to requirements of written form for arbitration agreement. The view was adopted by the Working Group that the objective of ensuring a uniform interpretation of the form requirement that responded to the needs of international trade could be achieved by : preparing a model legislative provision clarifying, for avoidance of doubt, the scope of article 7(2) of the UNCITRAL Model Law on International Commercial Arbitration : and adopting a declaration, resolution or statement addressing the interpretation of the New York Convention that would reflect a broad understanding of the form requirement. There was general agreement in the Working Group that, in order to promote the use of electronic commerce for international trade and leave the parties free to agree to the use of arbitration in the electronic commerce sphere, article II(2) of the New York Convention should be interpreted to cover the use of electronic means of communication as defined un article 2 of the Model Law on Electronic Commerce and that it required no amendment to do that. The UNCITRAL may wish to consider to the desirability of preparing uniform provisions on any of those issues concerning conciliation and arbitration proceedings, possibly indicating whether future work should be towards a legislative text or non-legislative text.

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