• 제목/요약/키워드: route finding

검색결과 169건 처리시간 0.028초

THE DEVELOPMENT OF THE SILK ROAD: THE POSTAL RELAY ROUTE OF MONGOL AND GORYEO

  • KIM, TSCHUNG-SUN
    • Acta Via Serica
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    • 제1권1호
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    • pp.105-117
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    • 2016
  • The Silk Road named by Ferdinand von Richthofen was not designated as a specific route. A lot of East-West trade routes had already existed across the continent and the geographical scope and definition of the Silk Road is still expanding. In particular, the claim that the Eastern end of the Silk Road reaches Gyeongju is an example of this expansion. Burial treasures from tombs on the Korean Peninsula have already been identified as products from the Sassanian Dynasty of Persia, and various archaeological and epical evidences support this finding. However, the specific route where these exchanges were made, around the 6th-8th centuries, has yet to be identified. Maritime as well as inland routes can easily be hypothesized. The Silk Road was largely activated by the Yam postal system with the expansion of the Mongol Empire. It not only served as an effective pathway for the Yuan to rule over the Goryeo, but also connected the Eastern end of the Silk Road to Gyeongju. This can explain the situation since the 13th century. Therefore, this paper claims that the Yeokcham system had been operating on the Korean Peninsula since the Unified Silla Kingdom, the previous period of Goryeo, or perhaps even before then. The Yeokcham should thus be regarded as a prototype of the Mongolian Yam, and the Korean peninsula should be recognized as another route which contributed specifically to the development of the Silk Road, not just as a user or a beneficiary.

A Study on Developing Navigation for a Moving Destination Target

  • Jang, Eun-Gyeom;Lee, Won Joo
    • 한국컴퓨터정보학회논문지
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    • 제21권9호
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    • pp.65-72
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    • 2016
  • Vehicle and marine navigation which are currently being commercialized provide route guidance service by specifying a fixed position as a destination. In the route guidance service of existing navigation, if the destination has to be changed in the middle, a new destination must be designated again to obtain the navigation service. However, if the destination can't be designated, it is difficult to clearly use it. In this paper, in order to overcome the difficulties of directions in the existing navigation, a new navigation specifying moving targets as the destination has been developed to get the directions. A proposed system is that a group is made and a group manager is appointed as a destination and then a user can get the route guidance based on location of the group manager. In the service way, relationship between the group manager and user is one-to-many and relationship between the user and group manager is one-to-one. The proposed technology is able to provide services that the user can easily find the moving targets such as the positioning surrogate drivers, tracking routes and location among travelers and finding children.

AODV 기반 모바일 Ad-hoc 네트워크의 노드 Disjoint 다중경로 라우팅 프로토콜 (A Node-Disjoint Multi-Path Routing Protocol in AODV-based Mobile Ad-hoc Networks)

  • 김태훈;정상화;강수영;유영환
    • 한국통신학회논문지
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    • 제34권12B호
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    • pp.1371-1379
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    • 2009
  • 본 논문에서는 모바일 노드들의 움직임이 심한 MANET 환경에서 데이터의 전송을 보다 안정적이고 신뢰성 있게 하기 위해 소스 목적지 간의 다중 경로를 찾는 새로운 방법을 제시하고자 한다. 새로운 다중경로 라우팅은 먼저 AODV에 기반을 두어 주경로를 설정하고 주경로로 설정된 노드는 보조경로 탐색에 참여하지 못하도록 하여 주경로와 보조경로를 노드 비 겹침(disjoint)하게 형성한다. 또한 주경로가 설정된 후 바로 데이터 전송을 시작하고 데이터 전송이 되고 있는 중에 백그라운드로 보조경로 탐색을 실행하여 경로 탐색 시에 발생하는 데이터 전송의 지연을 주경로 탐색 시에만 발생하도록 한다. 주경로와 보조경로 중 하나의 경로가 단절되면 즉시 다른 경로로 데이터 전송을 하게 되고 단절된 경로는 경로유지를 통해 다시 노드 비 겹침 경로를 찾는다. Qualnet 기반 시뮬레이션을 수행한 결과, 제안한 라우팅 프로토콜을 사용한 경우 주경로가 단절되었을 때 62.5%정도 보조경로가 존재하여 보조경로를 통한 지연 없는 데이터 전송을 하며, AODV, AODV-Local Repair에 비해 패킷 전송률이 2~3%향상되고, 종단 간 지연시간이 10%정도 줄어든다.

On Finding a Convenient Path in the Hierarchical Road Network

  • Sung, Ki-Seok;Park, Chan-Kyoo;Lee, Sang-Wook;Doh, Seung-Yong;Park, Soon-Dal
    • Management Science and Financial Engineering
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    • 제12권2호
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    • pp.87-110
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    • 2006
  • In a hierarchical road network, all roads can be classified according to their attributes such as speed limit, number of lanes, etc. By splitting the whole road network into the subnetworks of the highlevel and low-level roads, we can reduce the size of the network to be calculated at once, and find a path in the way that drivers usually adopt when searching out a travel route. To exploit the hierarchical property of road networks, we define a convenient path and propose an algorithm for finding convenient paths. We introduce a parameter indicating the driver's tolerance to the difference between the length of a convenient path and that of a shortest convenient path. From this parameter, we can determine how far we have to search for the entering and exiting gateway. We also propose some techniques for reducing the number of pairs of entries and exits to be searched in a road network. A result of the computational experiment on a real road network is given to show the efficiency of the proposed algorithm.

출발지와 도착지의 경로인지특성을 반영한 One-to-One 최적경로탐색 (출발지기반 수식 및 알고리즘을 중심으로) (Finding the One-to-One Optimum Path Considering User's Route Perception Characteristics of Origin and Destination (Focused on the Origin-Based Formulation and Algorithm))

  • 신성일;손기민;조종석;도철웅;김원근
    • 대한교통학회지
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    • 제23권7호
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    • pp.99-110
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    • 2005
  • 출발지와 도착지를 연결하는 경로의 총통행비용은 경로를 구성하는 링크통행비용과 경로인지비용의 합으로 구성된다. 링크인지비용이 출발지와 도착지에 따라 상이한 경우 경로인지비용을 고려한 최적경로탐색은 경로열거문제에 직면하여 현실 적용에는 한계가 있다. 본 연구에서는 출발지와 도착지 간 경로의 열거문제를 발생시키지 않으면서 경로상에 상이한 링크인지비용을 반영하는 최적경로탐색 최적식과 알고리즘을 제안한다. 경로의 최소단위를 링크로 정의하고 링크의 비교가 경로의 비교로 확대되는 최적경로탐색기법을 제안한다. 출발지와 목적지에서 링크의 인지특성을 반영하기 위하여 출발지기반 최적경로탐색과 목적지기반 최적경로탐색을 동시에 적용하는 방안을 제안한다. 양방향 탐색에 의한 경로탐색은 최적해가 보장되지 못하므로 목적지기반 최적링크인지경로트리를 먼저 구축하고 출발지기반 최적경로탐색의 제약조건으로 반영하는 수식과 알고리즘을 제안한다. 주변지 역에 대한 경로정보의 다양성과 도로위계에 대한 인지비용을 포함한 사례연구를 통해 제안된 수식과 알고리즘이 실제 교통망에서 출발지와 도착지의 특성이 반영된 경로인지행태를 적절하게 반영하는 지에 대하여 검토한다.

애드혹 네트워크에서의 보조 경로 설정 기법에 관한 연구 (A Study on Backup Route Setup Scheme in Ad Hoc Networks)

  • 정세원;이채우
    • 대한전자공학회논문지TC
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    • 제43권8호
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    • pp.47-58
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    • 2006
  • 애드 혹 네트워크는 노드의 이동에 의해 데이터 수신율의 저하, 지연 시간의 증가, 그리고 라우팅 오버헤드의 증가 등의 문제가 발생한다. 이를 해결하기 위한 보조 경로 기법은 노드의 이동에 의한 통신 성능 저하를 방지하기 위해 사전에 보조 경로를 설정해두어 링크 손상이 발생하더라도 패킷 손실이 없는 신속한 경로 복구가 가능하다. 보조 경로 기법은 노드의 이동이 잦은 상황에서 단일 경로 기법보다 데이터 수신율, 지연 시간, 및 라우팅 오버헤드 측면에서 더 좋은 성능을 보인다. 하지만 보조 경로 기법은 경로 탐색 단계에 설정된 보조경로만을 사용하기 때문에 네트워크 토폴로지 변화에 의한 새로운 보조경로를 사용하지 못한다. 본 논문에서 제안하는 리액티브 보조 경로 알고리즘(Reactive Backup Routing Algorithm, RBR)은 선택적 보조 경로 유지와 보조 경로 재 탐색을 통해 적은 오버헤드로 이동이 잦은 환경에서도 안정적인 데이터 수신율과 지연 시간을 보장하는 알고리즘이다. RBR은 설정된 모든 보조 경로를 주기적으로 확인하는 기존 방식과는 달리 보조 경로의 우선순위를 결정하고 보조 경로의 선택적 유지 및 사용으로 라우팅 오버헤드를 감소시킨다. 또한, RBR은 노드의 이동에 의해 보조 경로가 모두 손상되거나 경로가 변경되면 토폴로지 변화에 따라 새롭게 보조 경로를 설정하여 데이터 수신율을 높이고 지연 시간을 감소시킨다. 본 논문에서는 성능 검증을 위해 OPNET을 사용하여 단일 경로 기법 및 기존 보조 경로 기법과 RBR의 성능을 비교 분석한다.

수도권 복합 대중교통망의 복수 대안 경로 탐색 알고리즘 고찰 (A Study on Finding the K Shortest Paths for the Multimodal Public Transportation Network in the Seoul Metropolitan)

  • 박종훈;손무성;오석문;민재홍
    • 한국철도학회:학술대회논문집
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    • 한국철도학회 2011년도 정기총회 및 추계학술대회 논문집
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    • pp.607-613
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    • 2011
  • This paper reviews search methods of multiple reasonable paths to implement multimodal public transportation network of Seoul. Such a large scale multimodal public transportation network as Seoul, the computation time of path finding algorithm is a key and the result of path should reflect route choice behavior of public transportation passengers. Search method of alternative path is divided by removing path method and deviation path method. It analyzes previous researches based on the complexity of algorithm for large-scale network. Applying path finding algorithm in public transportation network, transfer and loop constraints must be included to be able to reflect real behavior. It constructs the generalized cost function based on the smart card data to reflect travel behavior of public transportation. To validate the availability of algorithm, experiments conducted with Seoul metropolitan public multimodal transportation network consisted with 22,109 nodes and 215,859 links by using the deviation path method, suitable for large-scale network.

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흡수경로에 따른 약물동태학적 고찰 (The Study on Pharmacokinetics According to the Administration Route)

  • 박민철;김환영;조은희
    • 한방안이비인후피부과학회지
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    • 제22권3호
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    • pp.95-107
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    • 2009
  • Objective : The purpose of this study is to search for more effective administraion route of herbal medicine. Methods : Pharmacokinetic issues with the methods in experimental papers, which deal with finding the effectiveness of two or more administration routes of herbal medicine, searched from KERIS, KSI, KISTI and KTKP, have been analyzed by, first, categorizing the papers and comparing the validity of administration routes. Results and Conclusions : 1. Upon comparing in total of 24 papers on the basis of each administration route, per oral(PO)-herbal acupuncture(HA) was most superior in terms of number in that there were 13 cases and PO-per rectal(PR) was next superior in that there were 5 cases. PO-per dermal(PD)-inhalation therapy(IT), PO-IT and PO-PR-HA had 3, 2 and 1 cases respectively. 2. Out of the total 24 papers which compares different administration routes, 16 of them were pharmacokinetically appropriate, whereas, the remaining 8 were pharmacokinetically inappropriate. 3. Comparisons were made between PO-HA, PO-PR, PO-IT, PO-PD-IT and PO-PR-HA routes. However, none of them was not particularly effective regardless of the administered medicine or target organ. 4. No route was particularly effective against a particular drug target as a result of comparing damaged liver, asthma, endometriosis and anti-inflammation. 5. In the case of Injinhotang in medicine comparison, HA tended to be more associated with hepatotoxicity over PO. However, Cordyceps Militaris Mycelia, Gagamsohaphyangwon and Hongdeungtang showed no prominent effective administration route.

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정교화 가능성 모형에 의한 IT 피교육자 신용 믿음 변화의 종단분석 (An Longitudinal Analysis of Changing Beliefs on the Use in IT Educatee by Elaboration Likelihood Model)

  • 이웅규
    • Asia pacific journal of information systems
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    • 제18권3호
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    • pp.147-165
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    • 2008
  • IT education can be summarized as persuading the educatee to accept IT. The persuasion is made by delivering the messages for how-to-use and where-to-use to the educatee, which leads formulation of a belief structure for using IT. Therefore, message based persuasion theory, as well as IT acceptance theories such as technology acceptance model(TAM), would play a very important role for explaining IT education. According to elaboration likelihood model(ELM) that has been considered as one of the most influential persuasion theories, people change attitude or perception by two routes, central route and peripheral route. In central route, people would think critically about issue-related arguments in an informational message. In peripheral route, subjects rely on cues regarding the target behavior with less cognitive efforts. Moreover, such persuasion process is not a one-shot program but continuous repetition with feedbacks, which leads to changing a belief structure for using IT. An educatee would get more knowledge and experiences of using IT as following an education program, and be more dependent on a central route than a peripheral route. Such change would reformulate a belief structure which is different from the intial one. The objectives of this study are the following two: First, an identification of the relationship between ELM and belief structures for using IT. Especially, we analyze the effects of message interpretation through both of central and peripheral routes on perceived usefulness which is an important explaining variable in TAM and perceived use control which have perceived ease of use and perceived controllability as sub-dimensions. Second, a longitudinal analysis of the above effects. In other words, change of the relationship between interpretation of message delivered by IT education and beliefs of IT using is analyzed longitudinally. For achievement of our objectives, we suggest a research model, which is constructed as three-layered. While first layer has a dependent variable, use intention, second one has perceived usefulness and perceived use control that has two sub-concepts, perceived ease of use and perceived controllability. Finally, third one is related with two routes in ELM, source credibility and argument quality which are operationalization of peripheral route and central route respectively. By these variables, we suggest five hypotheses. In addition to relationship among variables, we suggest two additional hypotheses, moderation effects of time in the relationships between perceived usefulness and two routes. That is, source credibility's influence on perceived usefulness is decreased as time flows, and argument quality's influence is increased. For validation of it, our research model is tested empirically. With measurements which have been validated in the other studies, we survey students in an Excel class two times for longitudinal analysis. Data Analysis is done by partial least square(PLS), which is known as an appropriate approach for multi-group comparison analysis with a small sized sample as like this study. In result. all hypotheses are statistically supported. One of theoretical contributions in this study is an analysis of IT education based on ELM and TAM which are considered as important theories in psychology and IS theories respectively. A longitudinal analysis by comparison between two surveys based on PLS is also considered as a methodological contribution. In practice, finding the importance of peripheral route in early stage of IT education should be notable.

전문가시스템을 이용한 최적경로 탐색시스템(X-PATH)의 개발 (Development of Optimal-Path Finding System(X-PATH) Using Search Space Reduction Technique Based on Expert System)

  • 남궁성;노정현
    • 대한교통학회지
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    • 제14권1호
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    • pp.51-67
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    • 1996
  • The optimal path-finding problem becomes complicated when multiple variables are simultaneously considered such as physical route length, degree of congestion, traffic capacity of intersections, number of intersections and lanes, and existence of free ways. Therefore, many researchers in various fields (management science, computer science, applied mathematics, production planning, satellite launching) attempted to solve the problem by ignoring many variables for problem simplification, by developing intelligent algorithms, or by developing high-speed hardware. In this research, an integration of expert system technique and case-based reasoning in high level with a conventional algorithms in lower level was attempted to develop an optimal path-finding system. Early application of experienced driver's knowledge and case data accumulated in case base drastically reduces number of possible combinations of optimal paths by generating promising alternatives and by eliminating non-profitable alternatives. Then, employment of a conventional optimization algorithm provides faster search mechanisms than other methods such as bidirectional algorithm and $A^*$ algorithm. The conclusion obtained from repeated laboratory experiments with real traffic data in Seoul metropolitan area shows that the integrated approach to finding optimal paths with consideration of various real world constraints provides reasonable solution in a faster way than others.

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