• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.5 no.3 s.11
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• pp.1-12
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• 2006

Nowdays ITS is being installed in each local autonomous entity, and BIS installation and operation is prior to other ITS sub systems for the public service. The methods of positioning md wireless communication in BIS are DSRC+DSRC, GPS+wireless communication, Beacon+Beacon, which are chosen and operated as the local features. Before this study, the before and after survey of BIS' quality have only been done without performance evaluation of BIS. So the method of BIS' evaluation have been established including performance test in this paper. And the evaluation of some BIS' reliability and efficiency have been done using the reliability of arriving data and the wireless communication response rates after choosing typical BIS' sub system.

• The Journal of the Korea institute of electronic communication sciences
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• v.10 no.5
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• pp.539-548
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• 2015

In this paper, shared memory feature was developed in multi-core system with different OS for different processor-specific bus, while conducting an experiment on shared memory feature between the two processors based on embedded Linux system. For the purpose of developing shared memory in dual bus structure, memory controller was used, while managing shared memory segment through list data structure. For AMP multi-core test, Linux OS was installed in 2 processor cores. In addition, it verified the creation and use of shared memory by using kernel module implemented to test shared memory.

• Journal of the Korea Institute of Information Security & Cryptology
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• v.30 no.6
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• pp.1023-1030
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• 2020

Wearable devices, such as a smart watch and a wrist band, store owner's private information in the devices so that security in a high level is required. Applications developed by third parties in Tizen request for an access to designated services through the desktop bus (D-Bus). The D-Bus verifies application's privileges to grant the request for an access. We developed a fuzzing tool, so-called DAN (the D-bus ANalyzer), to detect errors in implementations for privilege verifications and access controls within Tizen's system services. The DAN has found a number of vulnerable services which granted accesses to unauthorized applications. We built a proof-of-concept application based on those findings to demonstrate a bypass in the privilege examination.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.31 no.4D
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• pp.527-538
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• 2011

Currently, the only established criteria is on the location of bus stops on principal roads where uninterrupted flow mainly occurs. There are no clear guidelines on any method to locating bus stops considering the characteristics of bus operation and pedestrians. If the location or exterior of a bus stop is inappropriate, road users including bus drivers and pedestrians will be caused serious dangerous and inconvenience. In this study, the research below was performed in order to propose rational criteria for the location of bus stops integrated with or separated from speed-change lanes at signalized intersections considering smooth traffic flow and the characteristics of bus operation and pedestrians as well as traffic safety : First, the appropriate length of each of the near-side and far-side bus stops was calculated by categorizing bus stops to be constructed into those integrated with speed-change lanes and those separated from speed-change lanes. Secondly, the appropriate length of each of the bus stops divided into near-side bus stops and far-side bus stops and integrated with or separated from speed-change lanes was selected by considering the characteristics of pedestrians. Thirdly, whether the construction locations of bus stops were appropriate or not was determined based on the appropriate length of bus stops integrated with or separated from speed-change lanes, which was calculated and selected by considering traffic flow and the characteristics of pedestrians and considering traffic safety. The method for locating bus stops considering traffic flow, the characteristics of pedestrians, and traffic safety will be able to help suggestion criteria of bus stop and the location of safe and pleasant bus stops.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.7 no.6
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• pp.81-91
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• 2008

In this study, data collection delay time generated in bus information system is analysed and improvement on system reliability by minimizing the delay time is suggested. To minimize the data collection delay time (call setup time), factors on data collection phase are analyzed. Each connecting time that it occurs from wireless communication during data collection phase, is selected as a main effective variable and a model for selecting an optimum communication point to minimize the effect of data delay time by each connecting time is suggested. In this model, minimization of the point between the time carrying out wireless communication and vehicle moving time, is calculated and the difference between the bus arrival time and information delivered time to the passenger is reduced. The test results for the proposed model in BIS using a CDMA (Code Division Multiple Access) communication show that delay time in real system operation has been improved. The minimum data collection delay time based on optimal communication position leads to the better reliability for Bus Information System. This study can be applied to the selection of optimal communication position and detection position instead of empirical methods.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.8 no.5
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• pp.57-70
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• 2009

According to the change of the traffic conditions, the requirement of controlling the separated left(or right) turn, the median bus lane and bicycle signal is increasing. However, the traffic signal controller standard based on the four-set lights restricts to control the three-set lights which control the separated direction and kind of traffics. This study suggests the method to control the three-set lights signal by improving the hardware and software for the traffic signal controller which is operated currently in the traffic scene. The 6 output ports of Load Signal Unit(LSU) which is consisted of Pedestrian Red, Pedestrian Green, Red, Yellow, Arrow and Green signal reconstitute 2 rows of the Red, Yellow, Green for three-set lights while the Signal Map data's code values which control the signal step of an individual Ring and LSU are established to adjust the LSU's output ports(R1 Y1 G1 R2 Y2 G2) of the three-set lights. The effect of using the separated through/left turn and the median lane bus signal of three-set lights is analyzed from a Mangwoo intersection in Seoul. The results of analysis show that the delay time of the east-west direction where the median bus lane is operated is especially improved with over 70 sec/veh.

• The Science & Technology
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• v.32 no.10 s.365
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• pp.88-89
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• 1999

10여년간 카드개발에만 전념해온 경덕전자(주)는 카드한장으로 버스와 택시, 지하철 등 모든 대중교통 요금을 자동 지불하는 '하나로 교통카드 시스템'을 개발한 벤처기업이다. 하나로시스템은 현재 버스 3천5백여대, 1,2호 지하철 9백여대, 택시 7천6백여대에 이미 설치해 운영하고 있으며 고속도로 통행료와 주차요금을 포함시킬 수 있는 연구를 계속하고 있다. 자동인식분야에서 국내 시장의 74%를 장악하고 있는 경덕전자(주)는 세계 25개국에 대리점망도 구축했다.

• Journal of the Korean Society for Railway
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• v.3 no.4
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• pp.23-35
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• 2000

지난 30년간 수도권은 많은 변화를 겪어왔다. 무엇보다도 1970년에 948만 인에 불과하던 인구가 1990년에는 거의 투 배인 1,859만 인으로. 1998년에는 2,130만 인으로 계속 증가하였다. 버스만으로는 대중교수단의 역할을 수행할 수 없게 되자 1970년대 초반부터 도시철도를 건설하기 시작하였다. 이후 도시철도는 서울시전역에서 건설되기 시작해서 이제 서울시내 만에도 8개 노선, 총 연장 280 km의 지하철망을 구축하게 되었다. 지하철 외에 서울시 외곽 도시를 연결하는 7개 노선, 총 연장 172 km의 전철망 또한 구축되었다. 지하철망과 전철망을 합한 수도권내 도시철도망은 이제 14개 노선, 총 연장 452 km에 달하며, 승객수송 분담율에 있어서도 버스보다 더 높은 비중을 차지하고 있다. (중략)

• Journal of the Economic Geographical Society of Korea
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• v.18 no.4
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• pp.539-555
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• 2015

This study proposes the methodology for measuring the time-distance accessibility on the Seoul bus system based on the T-card transaction databases and analyzes the results. T-card transaction databases contain the time/space information of each passenger's locations and times of the departure, transfers, and destination. We introduce the bus network graph and develop the algorithms for time-distance accessibility measurement. We account the average speed based on each passenger's get-in and getoff information in the T-card data as well as the average transfer time from the trip chain transactions. Employing the modified Floyd APSP algorithm, the shortest time distance between each pair of bus stops has been accounted. The graph-theoretic nodal accessibility has been given by the sum of the inverse time distance to all other nodes on the network. The results and spatial patterns are analyzed. This study is the first attempt to measure the time-distance accessibility for such a large transport network as the Seoul bus system consists of 34,934 bus stops on the 600 bus routes, and each bus route can have different properties in terms of speed limit, number of lanes, and traffic signal systems, and thus has great significance in the accessibility measurement studies.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.5 no.2 s.10
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• pp.44-54
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• 2006

The share rate of bus mode has been decreasing continuously. To solve this problem, the local governments implement Bus Management System(BMS) or Bus Impormation System(BIS). In operating the public transportation preferential policy, it is very important to verify the effectiveness of the projects. This study performed the effectiveness of BMS through before and after study based on the field data. Moreover, this study analyzed the factors affecting to BMS. We anticipate that the results of this study would be useful reference in local government's BMS planning.