• Spatial Information Research
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• 제19권1호
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• pp.83-91
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• 2011

The route finding analysis is an essential geo-related decision support tool in a LBS(Location based Services) and previous researches related to route guidance have been mainly focused on route guidances for vehicles. However, due to the recent spread of personal computing devices such as PDA, PMP and smart phone, route guidance for pedestrians have been increasingly in demand. The pedestrian route guidance is different from vehicle route guidance because pedestrians are affected more surrounding environment than vehicles. Therefore, pedestrian path finding needs considerations of factors affecting walking. This paper aimed to extract factors affecting walking and charting the factors for application factors affecting walking to pedestrian path finding. In this paper, we found various factors about environment of road for pedestrian and extract the factors affecting walking. Factors affecting walking consist of 4 categories traffic, sidewalk, network, safety facility. We calculated weights about each factor using analytic hierarchy process (AHP). Based on weights we calculated scores about each factor's attribute. The weight is maximum score of factor. These scores of factor are used to optimal pedestrian path finding as path finding cost with distance, accessibility.

• Journal of Communications and Networks
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• 제5권3호
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• pp.266-274
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• 2003

One of the major issues in current on-demand routing protocols for ad hoc networks is the high resource consumed by route discovery traffic. In these protocols, flooding is typically used by the source to broadcast a route request (RREQ) packet in search of a route to the destination. Such network-wide flooding potentially disturbs many nodes unnecessarily by querying more nodes than is actually necessary, leading to rapid exhaustion of valuable network resources such as wireless bandwidth and battery power. In this paper, a simple optimization technique for efficient route discovery is proposed. The technique proposed herein is location-based and can be used in conjunction with the existing Location-Aided Routing (LAR) scheme to further reduce the route discovery overhead. A unique feature of our technique not found in LAR and most other protocols is the selective use of unicast instead of broadcast for route request/query transmission made possible by a novel reuse of routing and location information. We refer to this new optimization as the UNIQUE (UNIcast QUEry) technique. This paper studies the efficacy of UNIQUE by applying it to the route discovery of the Dynamic Source Routing (DSR) protocol. In addition, a comparative study is made with a DSR protocol optimized with only LAR. The results show that UNIQUE could further reduce the overall routing overhead by as much as 58% under highly mobile conditions. With less congestion caused by routing traffic, the data packet delivery performance also improves in terms of end-to-end delay and the number of data packets successfully delivered to their destinations.

• 대한원격탐사학회:학술대회논문집
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• 대한원격탐사학회 2003년도 Proceedings of ACRS 2003 ISRS
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• pp.843-845
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• 2003

Shortest Path Problems are among the most studied network flow optimization problems, with interesting applications in various fields. One such field is the route determination service, where various kinds of shortest path problems need to be solved in location-based service. Our research aim is to propose a route technique in real-time locationbased service (LBS) environments according to user’s route preferences such as shortest, fastest, easiest and so on. Turn costs modeling and computation are important procedures in route planning. There are major two kinds of cost parameters in route planning. One is static cost parameter which can be pre-computed such as distance and number of traffic-lane. The other is dynamic cost parameter which can be computed in run-time such as number of turns and risk of congestion. In this paper, we propose a new cost modeling method for turn costs which are traditionally attached to edges in a graph. Our proposed route determination technique also has an advantage that can provide service interoperability by implementing XML web service for the OpenLS route determination service specification. In addition to, describing the details of our shortest path algorithms, we present a location-based service system by using proposed routing algorithms.

• 한국산업정보학회논문지
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• 제16권5호
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• pp.45-54
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• 2011

현재 스마트 기기 용도의 다양한 시내버스관련 어플리케이션이 있으며, 시내버스의 도착시간, 노선정보 등의 정보를 제공하고 있다. 하지만, 사용자의 이동에 따른 다양한 방법을 제공하지 못 하고 있다. 이에 본 연구에서는 사용자의 6가지 패턴을 알고리즘으로 설계하고, 이를 이용하여 구현된 Server와 Android Application이 서로 교신하면서 사용자가 가고자하는 목적지로 이동하는 방법을 제공한다. 또 구글 맵과 위치기반정보를 통하여 탑승지와 환승지, 그리고 도착지를 지도상에 출력함과 동시에 사용자의 현재 위치도 함께 제공한다. 보다 실용적이고 효율적인 정보를 제공함으로써 사용자는 시내버스를 보다 쉽게 이용할 수 있다.

• 한국IT서비스학회지
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• 제14권1호
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• pp.217-236
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• 2015

The purpose of this study is to propose the effective location-based IoT service acceptance model by integrating ELM (Elaboration Likelihood Model) with UTAUT (Unified Theory of Acceptance and Use of Technology). The Partial Least Squares was used to analyze the causal relationships with respect to the effects of central route and peripheral route on acceptance intention. The results shows that central route has more significant impacts on perceived usefulness than peripheral route and CFIP (Concern for Information Privacy) weaken the relationship of acceptance intention and perceived usefulness. Our findings indicate some meaningful implications in the acceptance research of IOT services. First, we noted that the easy of use significantly affects the adoption of location-based IoT service. Furthermore, it is important to build the secured mechanism of privacy protection to adopt of location-based IoT service. Second, we tried to attempt the newly integrated approach to technical acceptance using UTAUT's variables and ELM by Petty and Cacioppo (1986). Finally this research empirically analyzed the adoption case of location-based IoT service which is not well-known yet within our country.

• 대한조선학회 특별논문집
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• 대한조선학회 2017년도 특별논문집
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• pp.63-66
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• 2017

All passenger ships aboard more than 36 passengers are to be able to easily find escape routes when the escape way by fire with flame spread were onboard vessel (incl. Ferry, Passenger, Ro-pax, Inland Ferry) It should be impossible by ordinary emergency lights. The international Maritime Organization (IMO) gives special requirement for luminescent evaluation onboard test procedure and applicable location of low location lighting. In order to maintain the residual light source for a certain time in the low location lighting with a strip-shaped light source, the light source material must be sufficiently exposed to the light due to the proper placement of the escape route. The lighting arrangement influence how maintain low location lighting strip luminescent which measured onboard in connection with what elements are mainly sustain luminescent.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2004년도 ICEIC The International Conference on Electronics Informations and Communications
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• pp.42-46
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• 2004

Mobile IP [9] was introduced to help the mobile user to be contacted with a single IP address even though the point-of-access changes. However, mobile IP creates the so-called 'triangle routing' which makes the delays for data packets longer, as well as creating unnecessary traffic at the home network of the mobile user. To overcome this, Route Optimization (RO) for mobile IP [1] was proposed, which eliminated the triangle routing phenomenon. But [l] requires that the network protocol stack of all existing hosts to change. Privacy is also another matter to be considered. This paper introduces a scheme called Peer Agent scheme to implement RO for mobile IP without requiring existing hosts to change. Method to preserve location privacy while still enabling RO is also considered.

• International Journal of Computer Science & Network Security
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• 제22권3호
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• pp.285-291
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• 2022

WSN is the major component for information transfer in IoT environments. Source Location Privacy (SLP) has attracted attention in WSN environments. Effective SLP can avoid adversaries to backtrack and capture source nodes. This work presents a Two-Level Randomized Sector-based Routing (TLRSR) model to ensure SLP in wireless environments. Sector creation is the initial process, where the nodes in the network are grouped into defined sectors. The first level routing process identifies sector-based route to the destination node, which is performed by Ant Colony Optimization (ACO). The second level performs route extraction, which identifies the actual nodes for transmission. The route extraction is randomized and is performed using Simulated Annealing. This process is distributed between the nodes, hence ensures even charge depletion across the network. Randomized node selection process ensures SLP and also avoids depletion of certain specific nodes, resulting in increased network lifetime. Experiments and comparisons indicate faster route detection and optimal paths by the TLRSR model.

• 인터넷정보학회논문지
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• 제12권4호
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• pp.173-180
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• 2011

오늘날, 3G와 WiFi 통신을 이용한 수많은 스마트폰용 위치기반 서비스들이 존재한다. 본 논문에서는 안드로이드 플랫폼에서 실행 가능한 발전된 위치 기반 응용 프로그램인 MARS를 제안, 개발하였고, 이를 기존 유사 서비스와 성능을 비교하였다. MARS는 기본적으로 경로 등록, 경로 검색, 경로 평가 등 3가지 기능을 사용자들에게 제공하며 이들은 웹 및 데이터베이스서버, 그리고 사용자의 이동 단말기에 의해 동적으로 관리된다. 사용자들은 스마트폰을 이용하여 위치 정보를 검색 및 업데이트할 때, 서버들은 필요한 정보를 제공하여 사용자들이 자유롭게 자신들이 등록한 정보를 추가, 수정, 그리고 제거를 할 수 있도록 하며, 다른 사용자의 정보에 대해서는 평가를 수행 할 수 있도록 한다. 이는 기존의 다른 지도 서비스들이 사용자들로부터 직접적으로 정보 입력을 허락하지 않는 것과 달리 사용자들에게 정보 입력을 담당하게 한다는 점에서 구별된다. 본 논문에서는 MARS의 구현 과정과 함께 각 동작에 대한 실험 결과를 보여주며, 마지막으로 기존 서비스들과의 성능 평가를 통해, MARS가 더 나은 성능을 제공할 수 있음을 설명하기로 한다.

• 국제학술발표논문집
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• The 8th International Conference on Construction Engineering and Project Management
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• pp.510-519
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• 2020

Within an intelligent automated cyber-physical system, the realization of the autonomous mechanism for data collection, data integration, and data analysis plays a critical role in the design, development, operation, and maintenance of such a system. This construct is particularly vital for fault-tolerant route-finding systems that rely on the imprecise GPS location of the vehicles to properly operate, timely plan, and continuously produce informative feedback to the user. More essentially, the integration of digital twins with cyber-physical route-finding systems has been overlooked in intelligent transportation services with the capacity to construct the network routes solely from the locations of the operating vehicles. To address this limitation, the present study proposes a conceptual architecture that employs digital twin to autonomously maintain, update, and manage intelligent transportation systems. This virtual management simulation can improve the accuracy of time-of-arrival prediction based on auto-generated routes on which the vehicle's real-time location is mapped. To that end, first, an intelligent transportation system was developed based on two primary mechanisms: 1) an automated route finding process in which predictive data-driven models (i.e., regularized least-squares regression) can elicit the geometry and direction of the routes of the transportation network from the cloud of geotagged data points of the operating vehicles and 2) an intelligent mapping process capable of accurately locating the vehicles on the map whereby their arrival times to any point on the route can be estimated. Afterward, the digital representations of the physical entities (i.e., vehicles and routes) were simulated based on the auto-generated routes and the vehicles' locations in near-real-time. Finally, the feasibility and usability of the presented conceptual framework were evaluated through the comparison between the primary characteristics of the physical entities with their digital representations. The proposed architecture can be used by the vehicle-tracking applications dependent on geotagged data for digital mapping and location tracking of vehicles under a systematic comparison and simulation cyber-physical system.