• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.22 no.4
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• pp.211-225
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• 2023

In the future, infotainment systems are expected to play a pivotal role in mobility ecosystems connecting users and vehicles. This study draws user-experience factors from reviews of Android Auto, a car infotainment application, and analyzes factors that affect satisfaction. The user-experience factors of infotainment have been redefined based on previous studies. To analyze actual user-experience factors, topics are obtained, applied, and interpreted from user discourse through topic modeling. Sentiment analysis and logistic regression are used to determine positive and negative user-experience factors that affect satisfaction. Results of the empirical analysis show that Ease of Use and Understandability are factors that have the greatest impact on satisfaction, and Flexibility, Safety, and Playfulness are factors that have the most critical effect on dissatisfaction. Therefore, this paper suggests ways to improve the satisfaction level of the infotainment system, and establishes a strategy accordingly.

• Archives of design research
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• v.19 no.4 s.66
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• pp.175-186
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• 2006

In the 21C, each nation controls exhaust fumes from automobiles and makes an effort to develop alternative energy because of serious environmental problem. Jechon area has many historical and cultural archeological sites. And Jechon city sponsors various cultural events. But the way of transportation which is connected with Jecheon and around sightseeing places is general and not ready yet. Therefore, if a special means of vehicle is developed, it could play an another role of sightseeing resources. Special identity of Jecheon area for establishment of green vehicle traffic system which gives Jecheon area specific character was investigated for theoretical background. Traffic system was studied for establishment of direction through existent successful case study. Moreover content, method, structure and advantage & shortcoming etc. of vehicle that use green energy resource such as solar car, fuel cell car, hybrid car, natural gas car etc. were examined. The suitable means of vehicle for Jechon area was proposed to three directions with research and investigation. After comparison and investigation by inquiry of each section's experts, the most suitable traffic system of which energy resource of car, form of vehicles, the complement, dimension of vehicles etc. were decided. Design proposal should be drawn according to process of automobile design in decided direction. Special Exterior design of vehicle that use green energy resource connecting Jecheon and around area should be suggested in Jecheon City Hall and Chungchong-bukdo provincial office for vivify image of cleanliness area.

• Korean Journal of Oriental Medicine
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• v.14 no.1
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• pp.145-160
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• 2008

Nelumbinis Semen(NS) has been used in traditional medicine to treat diseases such as depression and diarrhea. In inflammatory responses, microglia produces molecules which are known to play roles in the central nervous system. And we previously studied NS inhibited nitric oxide synthase and secretion of tumor necrosis factor alpha. To explore the global gene expression profiles in BV-2 microglial cell line treated with NS, microarray analysis was performed. The cells were treated with LPS or NS plus LPS for 30min, Ih, 3h, and 6h, respectively. Of 45,101 known genes, with cutoff value of 3-fold change in the expression, 340, 644, 280 and 219 genes were upregulated and 503, 570, 694 and 484 were downregulated in NS treated cells at each time point. The results of the present study shows that treatment of NS reversed the LPS-induced upregulation of such genes as Ecoxsackievirus and adenovirus receptor(CAR), pellino 1, and S100P binding protein. It is thought that microarrays will play an ever-growing role in the advance of our understanding of the pharmacologic actions NS.

• Wind and Structures
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• v.19 no.2
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• pp.145-167
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• 2014

Wind-vehicle-bridge (WVB) interaction can be regarded as a coupled vibration system. Aerodynamic forces and moment on vehicles and bridge decks play an important role in the vibration analysis of the coupled WVB system. High-speed vehicle motion has certain effects on the aerodynamic characteristics of a vehicle-bridge system under crosswinds, but it is not taken into account in most previous studies. In this study, a new testing system with a moving vehicle model was developed to directly measure the aerodynamic forces and moment on the vehicle and bridge deck when the vehicle model moved on the bridge deck under crosswinds in a large wind tunnel. The testing system, with a total length of 18.0 m, consisted of three main parts: vehicle-bridge model system, motion system and signal measuring system. The wind speed, vehicle speed, test objects and relative position of the vehicle to the bridge deck could be easily altered for different test cases. The aerodynamic forces and moment on the moving vehicle and bridge deck were measured utilizing the new testing system. The effects of the vehicle speed, wind yaw angle, rail track position and vehicle type on the aerodynamic characteristics of the vehicle and bridge deck were investigated. In addition, a data processing method was proposed according to the characteristics of the dynamic testing signals to determine the variations of aerodynamic forces and moment on the moving vehicle and bridge deck. Three-car and single-car models were employed as the moving rail vehicle model and road vehicle model, respectively. The results indicate that the drag and lift coefficients of the vehicle tend to increase with the increase of the vehicle speed and the decrease of the resultant wind yaw angle and that the vehicle speed has more significant effect on the aerodynamic coefficients of the single-car model than on those of the three-car model. This study also reveals that the aerodynamic coefficients of the vehicle and bridge deck are strongly influenced by the rail track positions, while the aerodynamic coefficients of the bridge deck are insensitive to the vehicle speed or resultant wind yaw angle.

• Proceedings of the KSR Conference
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• 2011.10a
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• pp.3278-3288
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• 2011

Bulk freight is transported by a freight car, ship and tank lorry without packaging in a state of particles or powders. In korea, the main bulk freight include oil, grain, coal, cement, iron ore and these are occupied nearly 30% of the volume of gross domestic freight transportation. Therefore it is in important to transport efficient bulk freight transport system for the improvement of national distribution competitive as raw material for industry. Generally environment-friendly transfer modes such as railway and sea transport play an important role in bulk freight transport due to the mass transfer characteristics of bulk freight. This study is carried out for examining the problem of oil, grain, coal, cement, ore transportation through analyzing distribution flow of items and understanding characters of transfer modes.

• Proceedings of the KOR-KST Conference
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• 1996.06a
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• pp.131-137
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• 1996

This paper discusses the necessity, strategy and objectives of the rail transportation recently developed in Shanghai. The objective should not be regarded just as a term project, but should be taken as an urgent mission with the 21st century, Shanghai should possess a network of about 100km of rail transport lines. To this end, the following measures are suggested : grade separation of all lines on elevated structures ; developing the rail car industries ; full utilization of all available transportation facilities ; optimizing the use of the space resources of highways ; bringing into play the initiatives of all parties concerned. Recently, it has become a popular consensus that the development of high-speed, safe, punctual, comfortable, non-pollution rail transport with large capacity is the best and only solution to Shanghai urban transportation. In this respect, this dissertation deals with the development strategy for current Shanghai rail construction, together with the infractructure in Shanghai, positioning the developing target; meanwhile, some proposals and solutions to hit this target will be put forward for the reference of leaders and experts.

• Transactions of the Korean Society of Automotive Engineers
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• v.8 no.4
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• pp.194-201
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• 2000

It is called vehicle pull when a vehicle drifts in the lateral direction under the straight-ahead motion with no steering or external input. Recently vehicle pull draws attention as one of the critical evaluation items from the customers on the vehicle quality. It is generally recognized that the vehicle pull is complex phenomena due to internal and external factors. In this paper the relations between vehicle pull and ire were investigated through close survey on the road test results from the final inspection of car manufactures. Through this investigation the factors are identified which play an important role in causing vehicle pull problem.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.10 no.1
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• pp.8-15
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• 2011

ATV(All Terrain Vehicle) has been developed to be used for agricultural fields on unpaved roads but now it is mostly used to transport a short distance and play leisure sports at mountains. Recently, main concerns on the automobile industry is developing not only a car safe, high fuel efficient and friendly related with environment but also two-wheeled vehicles. In order to maintain high fuel efficiency and safety of two-wheeled vehicle, it is essential that ATV should be set up differential gear. But we worried for ATV which had been set up differential gear not to run on unpaved roads. Therefore, it is necessary to develop LSD(Limited Slip Differential) that maintains existing advantages of ATV and ensures ATV to travel safely on roads. Now LSD equipped cars have a complicated structure, so setting up on ATV is unsuitable. Therefore, in this study, we have developed simple, small and well operating LSD.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 1996.04a
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• pp.25-28
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• 1996

This paper addresses the issues and difficulties encountered in developing a 12-axis measurement system for the assessment of whole-body vibration exposed from the body contact area. The contents of related survey work and the ideas from Professor Griffin in ISVR, that have led to its successful development, are introduced here. The developed 12-axis measurement system is shown to satisfy the international standards of ISO 2631 and BS 6841 in EC. This system is expected to play a key role in assessing the ride quality of passenger cars that is rapidly becomes much interest in Korean car-makers and tyre-makers.

• Proceedings of the KSR Conference
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• 2010.06a
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• pp.1542-1548
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• 2010

Transportation cost takes a major portion on logistics cost. The reduction of transportation cost is a key issue to achieve national competitiveness and logistics cost reduction. And railway must play a important role to shift from road freight transport to environment-friendly transport. There are many idle freight cars in railway freight transportation and they give rise to inefficient operation of freight car. It is well known that the main reason of idle freight cars is unbalanced demand according to direction. In this study, we analysed the current status on idle freight cars in railway at the level of daily data. This results help follow-up research to cut down idle freight cars in railway.