• The KIPS Transactions:PartC
• /
• v.17C no.3
• /
• pp.243-250
• /
• 2010

Vehicular communication networking is one of the most important building blocks of Intelligent Transportation System (ITS). The vehicular communication network is a wireless communication system enabling vehicles to communicate with each other as well as with roadside base stations. Mobility management of vehicles which move at high speeds and occasionally make a long journey is an interesting research area of vehicular communication networks. Recently, The Proxy Mobile IPv6 (PMIPv6) protocol is proposed for network-based mobility management to reduce the overhead of mobile nodes. PMIPv6 shifts the burden of the mobility management from mobile nodes to network agents to decrease the overhead and latency for the mobility management. In this paper, we derive the scenario of deploying PMIPv6 in vehicular communication networks and propose a new LMA handover mechanism for realizing the scenario. By carrying out the ns-2 based simulations, we verify the operability of the proposed mechanism.

• Journal of the Korea Institute of Information and Communication Engineering
• /
• v.13 no.8
• /
• pp.1587-1592
• /
• 2009

RFID is Playing a central role in ubiquitous technology according with the advent of the ubiquitous era, and the development of an RFID reader is also emerging as an important technical development field. In this paper, we developed a hardware system which is able to make use of the 13.56MHz RFID infrastructure being used as a transportation card, a credit card, and so on as well as the 125KHz RFID infrastructure being used in security company, and which is applicable to a location identification, an entrance and exit control, and security control over the TCP/IP communication. The existing local RFID methods have some problems which bottlenecks such as administrative problems, technical problems, and so force frequently occur because a casual server is placed and operated in a company. Hence, in this paper we developed an RFID multi reader which is connected to a central administrable server over the TCP/IP in order to solve these problems, and we make it be possible to keep an security control and be easy to install, transfer and administrate RFID infrastructures.

• Journal of the Korea institute for structural maintenance and inspection
• /
• v.16 no.1
• /
• pp.120-130
• /
• 2012

As long span and complex bridges are constructed often recently, safety estimation became a big issue. Various types of measuring instruments are installed in case of long span bridge. New wireless technologies for long span bridges such as sending information through a gateway at the field or sending it through cables by signal processing the sensing data are applied these days. However, The case of occurred accidents related to bridge in the world have been reported that serious accidents occur due to lack of real-time proactive, intelligent action based on recognition accidents. To solve this problem in this study, the idea of "communication among things", which is the basic method of RFID/USN technology, is applied to the bridge monitoring system. A sensor node module for USN based intelligent bridge system in which sensor are utilized on the bridge and communicates interactively to prevent accidents when it captures the alert signals and urgent events, sends RF wireless signal to the nearest traffic signal to block the traffic and prevent massive accidents, is designed and tested by performing TinyOS based middleware design and sensor test free Space trans-receiving distance.

• Journal of Korean Society of Transportation
• /
• v.18 no.1
• /
• pp.47-59
• /
• 2000

The purpose of this study is to develop travel-time estimation model using neural networks and prediction model using neural networks and kalman-filtering technique. The data used in this study are travel speed collected from inductive loop vehicle detection systems(VDS) and travel time collected from the toll collection system (TCS) between Seoul and Osan toll Plaza on the Seoul-Pusan Expressway. Two models, one for travel-time estimation and the other for travel-time Prediction were developed. Application cases of each model were divided into two cases, so-called, a single-region and a multiple-region. because of the different characteristics of travel behavior shown on each region. For the evaluation of the travel time estimation and Prediction models, two Parameters. i.e. mode and mean were compared using five-minute interval data sets. The test results show that mode was superior to mean in representing the relationship between speed and travel time. It is, however shown that mean value gives better results in case of insufficient data. It should be noted that the estimation and the Prediction of travel times based on the VDS data have been improved by using neural networks, because the waiting time at exit toll gates can be included for the estimation of travel time based on the VDS data by considering differences between VDS and TCS travel time Patterns in the models. In conclusion, the results show that the developed models decrease estimation and prediction errors. As a result of comparing the developed model with the existing model using the observed data, the equality coefficients of the developed model was average 88% and the existing model was average 68%. Thus, the developed model was improved minimum 17% and maximum 23% rather then existing model .

• Journal of Korean Society of Transportation
• /
• v.24 no.6 s.92
• /
• pp.89-102
• /
• 2006

The purpose of this paper is to develop a dynamic OD estimating model to overcome the limitation of depicting teal situations in dynamic simulation models based on static OD trip. To estimate dynamic OD matrix we used the hybrid discrete choice model(called the 'Demand Simulation Model'), which combines travel departure time with travel mode and travel path. Using this Demand Simulation Model, we deduced that the traveler chooses the departure time and mode simultaneously, and then choose his/her travel path over the given situation In this paper. we developed a hybrid simulation model by joining a demand simulation model and the supply simulation model (called LiCROSIM-P) which was Previously developed. We simulated the hybrid simulation model for dependent/independent networks which have two origins and one destination. The simulation results showed that AGtt(Average gap expected travel time and simulated travel time) did not converge, but average schedule delay gap converged to a stable state in transportation network consisted of multiple origins and destinations, multiple paths, freeways and some intersections controlled by signal. We present that the hybrid simulation model can estimate dynamic OD and analyze the effectiveness by changing the attributes or the traveler and networks. Thus, the hybrid simulation model can analyze the effectiveness that reflects changing departure times, travel modes and travel paths by demand management Policy, changing network facilities, traffic information supplies. and so on.

• Journal of Digital Convergence
• /
• v.14 no.12
• /
• pp.405-411
• /
• 2016

Seoul city is publishing new plans to increase modal share rate of bicycle every year, such as, maintaining bicycle related facilities. But bicycle's modal share rate in Seoul stayed same for the last decade and people are still facing difficulties using bicycle related facilities. These problems are causing bicycle usage as connecting transportation of public transit to decrease. This study looked at the high bicycle modal countries, such as, Netherlands, Germany and Japan to find applicable solutions by analyzing cases and comparing them with cases of highly populated subway station of Sindorim in Seoul. For example, in Germany and Netherlands there is bicycle-parking system to help bikers to access subway easier, in Japan there is underground bicycle parking tower to safely keep high volume of bicycles with in small space. For Seoul city to increase its modal share rate, they should look at problems from users' prospective and solve it by fixing it and improving the services, not by making more facilities.

• Proceedings of the ESK Conference
• /
• 1998.04a
• /
• pp.65-69
• /
• 1998

기존에 사용자 인터페이스 디자인 개발시 다양한 사용자 니즈들이 수집되고 이러한 정보들의 효과적 활용을 위하여 여러 가지 분석방법들이 활용, 개발되고 있다. 그중 Video Ethnography는 특정 시스템 상에서 나타나는 사용자의 행동을 중심으로 한 환경내의 변화를 비디오를 이용해 저장하고 저장된 상황 의 변화요인을 해석 체계에 의거해 분석하는 기법이다. 이는 기존의 다른 방법에 비해 사용자의 자연스 러운 작업의 수행을 분석하는 데 초점을 맞추고 있기 때문에 실험실에서 행해지는 계획된 실험에서 얻 을 수 없는 시스템에 관한 발견점을 찾아낼 수 있다는 장점이 있다. 하지만 현재 Video Ethnography를 수행하는 과정에서 수집된 사용성 정보들이 총체적인 관점에서 체계적으로 관리, 분석되지 못하고 있고, 관리 시스템의 부재로 인하여 비디오 데이터를 분석, 관리하는데 필요이상의 시간과 노력이 필요한 실정 이다. 본 연구에서는 이러한 어려움을 해결하고자 Video Ethnography를 통해 얻어진 사용자 니즈를 체 계적으로 수집,해석, 관리하는 효과적인 도구의 개발에 중점을 두었다. 특정한 사용상황에 맞추어 수집 된 다양한 형태의 사용자 니즈들은 먼저 컴푸터를 통해 입력되고 입력된 데이터는 과업의 목적, 주변상황, 시스템과 사용자와의 상호작용 등 다양한 변수에 의해 분석된다. 이러한 분석의 과정을 통해특정 시스템 에 대한 사용자의 니즈가 도출되고 새로운 디자인 해결안이 제시될 수 있는 것이다. 이러한 일련의 과정 은 사용자 니즈 데이터베이스로 구축되며 추후 제품 개발의 근거로서 활용될 수 있다. 앞으로 다양한 사 용환경에 대한 사용자 니즈 데이터베이스가 확충되면 각 사용상황하의 사용성 문제 해결안뿐만 아니라 서로 관련이 있는 사용상황간의 연계 연구를 통해 좀 더 광범위한 개념의 제품 개발도 가능해 질 수 있을 것이다.와 만족도와의 관계 및 이상형에 대해 구체적으로 파악할 필요가 있다. 또한, 신체에 대한 이상형은 시대의 여러 여건에 따라서 변화할 수 있으므로 의복 착용자가 의복을 통해서 표현하고자 하는 이상형의 시대적 변화를 살펴볼 필요가 있다. 따라서 본 연구에서는 신체에 대한 인식도 및 만족도, 이상형에 대한 설문지 조사와 신체측정을 통하여 신체 크기에대한 만족도를 객관적인 척도로 고찰하고, 이상형과 실제 체형에 관하여 고찰하고자 한다. 도한, 1992년도 자료와의 비교를 통하여 시대에 따른 신체만족도와 이상형의 변화를 파악하고자 한다. 이를 기초로 한 의복원형 제작 및 의복 디자인에 대한 연구를 통해 의복의 맞음새가 좋을뿐만 아니라 의복착용자들 에게 심리적 만족을 줄 수 있는 의복 제작에 도움이 될 수 있을 것이다.적입지로 분석되었다.등 다양한 모형들을 고려해 본 뒤, 적절한 모형을 적용할 것이다. 가로망 설계 모형에서 신호제어를 고려하기 위해서는 주어진 가로망에 대한 통행 배정과정에서 고려되는 통행시간을 링크통행시간과 교차로 지체시간을 동시에 고려해야 하는데, 이러한 문제의 해결을 위해서 최근 활발히 논의되고 있는 교차로에서의 신호제어에 대응하는 통행배정 모형을 도입하여 고려하고자 한다. 이를 위해서 지금까지 연구되어온 Global Solution Approach와 Iterative Approach를 비교, 검토한 뒤 모형에 보다 알맞은 방법을 선택한다. 차량의 교차로 통행을 고려하는 performance function의 경우 비신호 교차로와 신호교차로에 대한 적절한 비교가 현재로서는 고려되고 있지 못하기 때문에, 구성되는 가로망의 경우 신호교차로들로만 구성되며, 부득이한 경우 입체교차의 형태로 구성되는 것으로 가정한다. 실제 가로망의 경우, 교통향이 많은 도시부의 경우 주가로망은 대부분 신호교차로와 입체교차로 구성되기 때문에

• Journal of Convergence for Information Technology
• /
• v.11 no.4
• /
• pp.19-25
• /
• 2021

This study proposes a digital twin implementation method through simulation so that the manufacturing process can be optimized in a manual manufacturing site. The scope of the proposal is a knowledge management mechanism that collects manual motion with a sensor and optimizes the manufacturing process with repetitive experimental data for motion recognition. In order to achieve the research purpose, a simulation of the distribution site was conducted, and a plan to create an optimized digital twin was prepared by repeatedly experiencing the work simulation based on the basic knowledge expressed by the worker's experience. As a result of the experiment, it was found that it is possible to continuously improve the manufacturing process by transmitting the result of configuring the optimized resources to the physical system by generating the characteristics of the work space configuration and working step within a faster time with the simulation that creates the digital twin.

• Journal of the Korean Society for Railway
• /
• v.13 no.4
• /
• pp.412-418
• /
• 2010

This paper presents the methods to acquire the Safety Certificate from Independent Safety Assessment based on the IEC standard62279 which is commonly applied to railway system for Automatic Train Control(ATC) system in accordance with Urban Maglev project. This also shows approach methods and relative activities for project life- cycle to accomplish and ensure the system requirements of ATC system, RAMS and S/W quality activities. Furthermore, the key tasks conducted with ISA are noted in detail. These kind of activities for software quality of ATC system to obtain S afety Certificate could be a CASE model to improve the quality of domestic railway system and products, and also contribute to the growth of railway business and toward the achievement of overseas' railway signaling markets.

• 한국공간정보시스템학회:학술대회논문집
• /
• 2005.05a
• /
• pp.53-58
• /
• 2005

21세기 지식정보화사회로 접어들어 GIS가 부각됨에 따라 GIS의 활성화를 위한 기본지리 정보에 대한 중요성이 대두되고 있다. 기본지리정보를 관리 감독하는 국토지리정보원에서는 2000년부터 기본지리정보구축에 관한 연구 등을 수행하여, 기본지리정보의 범위 선정과 데이터모델 표준화가 이루어 졌으며, 기본지리정보 유통과 구축에 필요한 생산사양이 이루어짐에 따라 기본지리정보의 품질 및 활용성에 대한 검토가 필요한 실정이다. 본 연구에서는 시설물분야 기본지리정보 생산사양에 따른 기본지리정보를 3단계에 걸쳐 구축하였으며 기 구축된 교통, 수자원, 행정경계 기본지리정보와 통합하여 활용성 평가를 수행하였다.