• Transactions of the Korean Society of Automotive Engineers
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• v.6 no.6
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• pp.1-6
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• 1998

A leaf spring plays an important role in a passenger bus. Since characteristic of a leaf spring has a hysteresis behaviour, modeling technique for a leaf spring is an important issue for passenger bus analysis. In this paper, modeling technique for a leaf spring is presented. First, non-linear FEM model of a leaf spring is constructed then it is used to make an approximated model to be used in dynamic analysis. The modeling procedure is ex-plained in step by step approach. Then, this model is applied to dynamic analysis of a mini-bus with flexible body and non-linear dynamic force element. The results are compared with test data.

• Journal of IKEEE
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• v.27 no.3
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• pp.355-367
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• 2023

Local Interconnect Network (LIN) is a low-speed in-vehicle network bus, and it is widely used in body applications such as windows, doors, HVAC, and lighting. This review explains protocols and message frames of LIN bus in detail. LIN bus basically transmits ID and payloads in data frame. How to interpret ID and payloads is defined in LIN Description file (LDF). Each LIN bus has unique LDF and its corresponding unique configuration. This review also explains syntax and example of LDF in detail.

• Journal of Auto-vehicle Safety Association
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• v.16 no.1
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• pp.49-54
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• 2024

This paper provides an analysis of the experimental procedures and results to ensure the reliability of the system manufactured for testing the hydrogen permeability of a 175 L compressed hydrogen container for a hydrogen bus. Based on the hydrogen permeability standard of 6 cc/(h·L), it was injected into the permeability test chamber at 10% intervals, and the permeated hydrogen concentration according to the injected amount was measured and compared with the actual amount of hydrogen permeated. As a result of the experiment, the measured value represented 96.34% of the actual permeation amount, which can be used as basic data for the hydrogen bus vessel permeability test system being built in Korea.

• 전자공학회논문지 IE
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• v.45 no.3
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• pp.5-12
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• 2008

We propose efficient scan testing method capable of reducing the test data and power dissipation for digital logic circuits. The proposed testing method is based on a hybrid run-length encoding which reduces test data storage on the tester. We also introduce modified Bus-invert coding method and scan cell design in scan cell reordering, thus providing increased power saving in scan in operation. Experimental results for ISCAS'89 benchmark circuits show that average power of 96.7% and peak power of 84% are reduced on the average without fault coverage degrading. We have obtained a high reduction of 78.2% on the test data compared the existing compression methods.

• Journal of Korean Society of Transportation
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• v.17 no.5
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• pp.123-135
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• 1999

The rapid increase of Passenger cars which is caused by the discomfort of Public transit and the Preference of automobiles is the major factor of increasing traffic congestions in Seoul With the point that leading the automobilists to the Public transit can be the most important Policy to ease these traffic congestions, this study focuses on the behavioral aspects of company employees and university students and investigates factors influencing bus ridership. To be brief, by estimating bus ridership through count models, this study investigates factors which influence bus ridership and elicits Political suggestions which lead automobilists to Public transit. The Purpose in this study is the application of appropriate count data model. The count data models have been widely applied to the economic area from the middle of the 1980s and to transportation aspect mainly in the foreign countries from the latter half of the 1980s. Even though a few studies in this country employed count data model to count data. all of them were Poisson regression models without suitable tests for the importance of the model specification. In the end, as the result of statistical test, negative binomial regression model which is suitable for overdispersed data was found to be appropriate for the data of weekly bus ridership. To emphasize the importance of model specification, both of poisson regression model and negative binomial regression model were estimated and the results were compared.

• Journal of the Economic Geographical Society of Korea
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• v.15 no.2
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• pp.332-342
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• 2012

The current research aims at classifying the bus stops as transfer center in order to establish the rational bus transfer systems. Existing research typically identifies characteristics of demands for bus stops and land use surrounding the bus stops and classifies and profiles the bus stops. A common problem with this type of research is that the results with cross-sectional characteristics of land use and bus stop usage do not capture the details of trip chain, the fundamental characteristics of the trips with transfer. This paper therefore examines bus stop classifications with such variables as transport mode chains, intermediate stop chains and timing chains. The analysis on the data collected on Monday 20 April 2009 for passengers of Gyeong-gi bus results in a clear classification among bus stops in terms of such trip chain variables. The research would provide useful information for the decision support of transfer stops location choice and infrastructure design.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.10 no.5
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• pp.14-22
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• 2011

This study is to estimate delay time model of signalized intersection by using travel data of Bus Information System. BIS, which applies the advanced information technology to an existing bus system, has been developing and operating in many cities. However, even though some useful traffic informations have been collected from BIS operation, utilization of real-time data to the traffic operation has not been promoted due to the inhomogeneity of modal speeds. Accordingly, in this study, a fundamental research is performed for traffic controls in urban areas and providing a traffic information throughout a methodology for estimating delay time using the data from BIS was developed. This delay time model setting bus travel time excluding service time of a bus stop as explanatory variables was constructed as a regression model, and the coefficient of determination of a linear regression model most highly appeared as 0.826. As a result of performing T-test with field survey values and model estimation values for verifying constructed models statistically, it was analyzed to be statistically significant in a confidence level of 95%.

• Journal of Korean Society of Transportation
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• v.27 no.6
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• pp.45-53
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• 2009

This study presumes the efficiency of each route by utilizing data of Seoul's exclusive bus routes for the 2008 and the DEA model. In the estimation, it is assumed that the number of passengers and profits of each route is calculated by considering the number of buses and stops, travel distance, intervals and management cost. This study computed the efficiency scores of each bus line in Seoul based on the data for the first half of 2008 and one of the DEA models, namely the BCC model. After analysis using the input-oriented BCC model, out of a total of 18 lines of interest, there were 2 CRS lines and 16 IRS lines. Also, the Tobit Regression Analysis that helps identify the impact of the elements used in the analysis on efficiency scores proved that the most influential element to exclusive buses is the length of intervals.

• Smart Media Journal
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• v.1 no.1
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• pp.27-35
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• 2012

In this paper, the performance analysis for multimedia video codec(MPEG-4, H.264) on on-chip network communication architecture is presented. The On-Chip Network (OCN) is the new communication architecture of multimedia SoC design that overcomes the limits of On-Chip Bus architecture by providing higher data traffic bandwidth, reusability and higher scalability. We compared the performance of MPEG-4, H.264 decoder based on-chip network and AMBA on-chip bus. Experimental results show that the performance of MPEG-4, H.264 based on on-chip network is improved over 33~56% compared to the design based on AMBA on-chip bus.

• 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.