• Title/Summary/Keyword: U-Car

Search Result 108, Processing Time 0.026 seconds

A Study on Development of Brake System of Light Eco-Friendly Car Considering Heat Load and Regenerative Braking Characteristic (열부하 및 회생 제동 특성을 고려한 경형 친환경차의 제동시스템 개발에 관한 연구)

  • Shim, J.H.;Shin, U.H.;Lee, J.H.;Hwang, S.R.;Yim, W.S.;Kim, B.C.
    • Journal of Auto-vehicle Safety Association
    • /
    • v.12 no.2
    • /
    • pp.7-13
    • /
    • 2020
  • Recently, there is a big issue of downsizing on brake system according to fuel efficiency and regenerative braking cooperation control. Especially, small cars have improved in a variety ways such as electric vehicle and smart car compared to previous small cars. So, small brake system is strongly required in the car industry. A new small brake system for light compact vehicles was proposed in this paper. For this system, the solid type disc and caliper were newly developed. And the important design factors were considered to reduce brake size. First, we calculated the temperature rise of disc through heat capacity formula and CAE analysis. Second, we analyzed the housing and carrier stiffness of caliper to select the reasonable condition. Finally, the superiorities of the developed brake system were verified by heat capacity, consumption liquid level, braking feeling, judder, wear test and regenerative braking cooperation control analysis. A developed brake system is expected to be useful for brake system of light compact platform.

입환 작업을 위한 RFID 실증 연구

  • Won, Jong-Un;Na, Hui-Seung;Jang, Yun-Seok
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
    • /
    • 2009.11a
    • /
    • pp.145-145
    • /
    • 2009
  • In this paper, we suggest how to adapt RFID system to train switching process, and then what we get the merit or problem. We analyze the train switching process to adapt RFID system on the process and have field test. The role of RFID system in train switching process is to automatically read car position information. The specification of the test system is 900MHz, and Gen2 passive tag. If we get the system which automatically read car position information in train switching yard, it prevents human errors and makes more reliability, the performance of train operation will grow up. Even though the environment of train switching yard is outdoors, the test result gives us the ability to adapt RFID system to train switching process and the process will be more simple.

  • PDF

경쟁력제고를 위한 한국 자동차산업의 최적 유통구조에 대한 소고

  • 전달영
    • Journal of Distribution Research
    • /
    • v.2 no.1
    • /
    • pp.59-85
    • /
    • 1997
  • The automobile industry in Korea has grown to the fifth in the world in terms of production capacity. In spite of the production growth, the marketing aspects such as distribution and customer service in the auto industry are still behind the world-class. Thus, the major purposes of this paper are as follows. The first is to analyze competitive structure of the industry and to compare distribution strategies of the major auto firms(Hyundai, Daewoo, and Kia). The second is to theoretically explain the transition from the vertical marketing system to the dealer system using transaction cost analysis. The third is to compare auto distribution channels in Korea with those in the U.S. and Japan. Finally, an optimal channel stucture in the auto industry is suggested after reviewing five alternative channel structures such as corporate-owned VMS, sales-specializing firm, multiplex system(VMS+limited dealer system), dual sales channel, and advanced dealer system. In the short-run, sales-specilizing firm was suggested as an optimal channel system to enhance customer satisfaction by integrating sales and customer service. In the long-run, advanced dealer system through regional differentiation was desirable for an optimal channel structure by organically integrating new car sales, used car sales, and after service to provide total marketing service to customers.

Freedom Cooperative Automotive Research (산.학.연 공동 프로젝트 "FreedomCAR")

  • Choi, Dae
    • Journal of the korean Society of Automotive Engineers
    • /
    • v.25 no.3
    • /
    • pp.34-37
    • /
    • 2003
  • 미국내에서 National Benefits와 관련하여 언급되고 있는 각종 Program 가운데 에너지 유효이용을 목적으로 하는 Energy 관련 Program이 주목을 받고 있다. 차세대 첨단 자동차 기술개발을 통한 에너지 유효이용 또한 프로그램 목표 달성을 위한 주요 수단이 되고 있다. 따라서 이를 참고하는 것을 미국 자동차 기술개발의 미래를 가늠하는데 도움이 될 것이라 판단된다. 다만, 일본.독일 등을 포함한 자동차 기술선진국들과는 달리, 미연방을 구성하고 있는 각 주마다 나름대로의 독특한 장.단기프로그램을 갖고 시행하고있기 때문에 미국을 대표하면서도 포괄적인 기술개발 동향을 파악하는 것은 그다지 쉬운 일이 아니다. 따라서 가능하다면 미국내 산.학.연을 모두 연계하는 R&D 프로그램을 참조하는 것이 유익하다 하겠다. 대표적인 예로서 미연방정부의 Department of Energy에 의해 시행되고 있는 $\ulcorner$FreedomCAR$\lrcorner$ Program을 들 수 있는데, 이는 상기 조건을 만족하는 첨단 자동차 기술개발을 위한 장기 프로젝트라 할 수 있다.

  • PDF

Human Sensibility Ergonomics Investigation of Car Navigation System Digital Map Color Structure

  • Cha, Doo-Won;Park, Peom
    • Journal of Korean Society of Industrial and Systems Engineering
    • /
    • v.23 no.60
    • /
    • pp.47-55
    • /
    • 2000
  • Two experiments were conducted to examine the relationships between the color structure and the user preference of a CNS (Car Navigation System) digital map in terms of HSE (Human Sensibility Ergonomics). In the first experiment, the user's preference of color structures were investigated from the subjects' self-designed digital maps using a CNS digital map UIMS (User Interface Management System): in the second, statistical relation models between the user's color structure satisfaction level and the color components of CIE (Commission Internationale de ι'Eclairage) of the real products were suggested. For each experiment, CIE L*u*v* and CIE LCH color space were adapted, respectively, because they have their own characteristics of perceptual uniformity which enables the color components to transform a linear function.

  • PDF

FCM Algorithm for Application to Fuzzy Control

  • KAMEI, Katsuari
    • Proceedings of the Korean Institute of Intelligent Systems Conference
    • /
    • 1998.06a
    • /
    • pp.619-624
    • /
    • 1998
  • This paper presents a new clustering algorithm called FCM algorithm for the design of fuzzy controller. FCM is an extended version of FCM(Fuzzy c-Means) algorithm and can estimate the number of clusters automatically and give membership grades $u_{ik}$ suitable for making fuzzy control rules. This paper also shows an example of its application to the line pursuit control of a car.

  • PDF

Design and fabrication of the GPS antenna system including RF-stage (RF 수신부를 내장한 GPS 안테나 시스템의 설계 및 제작)

  • 홍성일;이정호;변건식;정만영
    • Journal of the Korean Institute of Telematics and Electronics A
    • /
    • v.33A no.6
    • /
    • pp.99-107
    • /
    • 1996
  • When GPS (global positioning system) is used as synchronous signal in CDMA digital cellular base station system and high speed digital synchronous communication network, antenna cable length is increased, comparing with other GPS application such as positioning or car navigation. In this paper, it is proposed that a type of new GPS antenna system including RF stage for reduction of cable loss in case of long cable.The antenna system with TMPA(truncated-corners microstrip patch antenna) is designed and fabricated because GPS signal has RHCP (right-hand circular polarization), consequently antenna size can be made small size. LNA (low noise amplifier) is designed by using HEMT(high electron mobility transistor)which has lower noise figurae and better AGC characteristics at low voltage than GaAs FET, and we equiped mixer, in GPS antenna unit, which converts from 1575.42MHz to 75.42MHz. As result of comparing between typical system and proposed system when cable length is 60m, 63dB, 55dB and 25dB gain are obtained for RG-316/U, RG-58C/U and RG-213/U, and better characteristics are achieved than typical system as far as cable length is longer.

  • PDF

Brand Personality of Global Automakers through Text Mining

  • Kim, Sungkuk
    • Journal of Korea Trade
    • /
    • v.25 no.2
    • /
    • pp.22-45
    • /
    • 2021
  • Purpose - This study aims to identify new attributes by analyzing reviews conducted by global automaker customers and to examine the influence of these attributes on satisfaction ratings in the U.S. automobile sales market. The present study used J.D. Power for customer responses, which is the largest online review site in the USA. Design/methodology - Automobile customer reviews are valid data available to analyze the brand personality of the automaker. This study collected 2,998 survey responses from automobile companies in the U.S. automobile sales market. Keyword analysis, topic modeling, and the multiple regression analysis were used to analyze the data. Findings - Using topic modeling, the author analyzed 2,998 responses of the U.S. automobile brands. As a result, Topic 1 (Competence), Topic 5 (Sincerity), and Topic 6 (Prestige) attributes had positive effects, and Topic 2 (Sophistication) had a negative effect on overall customer responses. Topic 4 (Conspicuousness) did not have any statistical effect on this research. Topic 1, Topic 5, and Topic 6 factors also show the importance of buying factors. This present study has contributed to identifying a new attribute, personality. These findings will help global automakers better understand the impacts of Topic 1, Topic 5, and Topic 6 on purchasing a car. Originality/value - Contrary to a traditional approach to brand analysis using questionnaire survey methods, this study analyzed customer reviews using text mining. This study is timely research since a big data analysis is employed in order to identify direct responses to customers in the future.

VTA* Algorithm: A* Path-Finding Algorithm using Variable Turn Heuristic (VTA* 알고리즘: 가변적인 턴 휴리스틱을 적용한 A* 경로탐색 알고리즘)

  • Kim, Ji-Soo;Cho, Dae-Soo
    • Journal of the Korea Institute of Information and Communication Engineering
    • /
    • v.14 no.3
    • /
    • pp.663-668
    • /
    • 2010
  • In driving a car, turns such as left turns, right turns, or u-turns, make the speed of the car decrease considerably. A more straight path, therefore, is probably faster to arrive at the destination than zig-zag path with same distance. In this paper, we have newly proposed the turn heuristic to make more straight path. The path navigation algorithm with turn heuristic(called as TA* algorithm) could enhance the straightness of a path by putting the turned-edges to the turn cost. It requires higher cost to use TA* algorithm than traditional A* algorithm because the straight-edge first searching have increased the search space. We have improved the TA* algorithm into the variable TA* algorithm(called as VTA* algorithm) which adopt the turn-heuristic during the a portion of the whole path.

Sensitivity Analysis of Engine Mount System using FRF-based Substructuring Method (전달함수합성법을 이용한 엔진마운트계의 민감도 해석)

  • Lee, Du-Ho;Hwang, U-Seok;Kim, Chan-Muk
    • Transactions of the Korean Society of Mechanical Engineers A
    • /
    • v.25 no.1
    • /
    • pp.153-160
    • /
    • 2001
  • A general procedure for the design sensitivity analysis of structural dynamic problems has been presented in frame of the FRF-based substructuring formulation. For a system response function, the proposed method gives a parametric design sensitivity formula in terms of the partial derivatives of the connection element properties and the transfer matrix of the subsystems. The derived design sensitivity formula is applied to an engine mount system. An interior noise problem in the passenger car is analyzed using the FRF-based substructuring method and the proposed formulation is adopted to study the response variations with respect to the dynamic characteristics of the engine mounts and the bushes. To obtain the FRFs, a finite element model is built for the engine mount structures, and test data is used for the trimmed body including cabin cavity. The comparison of sensitivities derived by the proposed method and the finite difference method shows that the proposed method is efficient and accurate. The proposed sensitivity analysis method indicates effectively the most sensitive location to the interior noise among the engine mounts and the bushes.