• Title/Summary/Keyword: self-operated

검색결과 389건 처리시간 0.027초

Water Lubricated Guide Bearing with Self-aligning Segments

  • Oguma, Tadashi;Nakagawa, Naritoshi;Mikami, Makoto;Thantrong, Long;Kizaki, Yasumi;Takimoto, Fumio
    • International Journal of Fluid Machinery and Systems
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    • 제6권2호
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    • pp.49-55
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    • 2013
  • Water lubricated guide bearing was newly released and has been applied to actual hydro turbines with vertical shaft. As a result, they can have not only high bearing performance but environmental advantages in meeting the demand for reducing river pollution by oil leakage from oil lubricated guide bearing. The PTFE composite guide bearing was tested by experimental equipment operated under conditions similar to those of actual hydro turbines. Circumferential and axial tilting bearing segments help to improve the bearing performance and efficiency due to low friction loss in the bearing system. Furthermore, bearing cooling systems could be eliminated and maintenance periods could be extended, thus the initial investment and operating costs of the hydroelectric power plant are reduced.

대학 구내식당의 이용실태 및 급식 서비스에 대한 만족도 조사-서울지역을 중심으로- (A Study on Attitude and Satisfaction of Service Quality in University Foodservices)

  • 박수정;김진아;이심열
    • 동아시아식생활학회지
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    • 제14권1호
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    • pp.83-91
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    • 2004
  • The purposes of the study was to measure attitude and satisfaction concerning the service quality of university foodservices. The survey was conducted to 500 university students using questionnaires, of which 457 questionnaires were analyzed. A statistical data analysis was completed using SAS programs by the descriptive analysis. The results of the study were summerized as follows: 1) The mean frequencies of visiting the university foodservices per week were higher in males than females. The factor affecting the students on their first choice of the foodservices depended on the distance. The first complaint factor concerning the university foodservices was the taste of foods. 2) The students were not satisfied with the service quality of university foodservices personnels. The actual mean score of the service quality was 3.92 out of 5, but the perceived one was 2.94. Therefore, the satisfaction degree of the service quality was calculated as-0.98. 3) The students were more satisfied with the food quality of contracted foodservice management than that of self-operated one.

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6자유도 조작장치의 설계와 기구학적 특성에 관한 연구 (A study on the design and characteristics of kinematics of 6 degree-of-freedom manipulators)

  • 김정태;김문생
    • 대한기계학회논문집A
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    • 제22권2호
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    • pp.467-475
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    • 1998
  • The Six Degree-of-Freedom manipulators are generally operated by linear actuators which are hydraulic cylinder, pneumatic cylinder, ball-screw. But these actuators are not adequate to have a wide work-space, and furthermore some of them have a self-locking property. Therfore, we have designed a new manipulator which fully overcomes these demerits. The new manipulating system consists of 6 DC-motors to generate operation forces and 6 position transducers to feedback displacement signals. This paper presents an overview of the design and characteristics of 6 Degree-of-Freedom force feedback manipulators for vitual reality implementation. we can operate Six Degree-of-Freedom manipulator with six motors and six potentiometers.

5-Tap Adaptive PRML Architecture for High-Density Optical Disc Channel

  • Choi, Goang-Seog
    • 한국멀티미디어학회논문지
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    • 제10권12호
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    • pp.1585-1590
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    • 2007
  • This paper introduces adaptive PRML (Partial Response Maximum Likelihood) architecture with PR (a,b,c,d,e) channel type for the improved readability of high-density optical discs with capacity greater than 30GB. The proposed PRML architecture consists of an adaptive equalizer, a Viterbi detector and a channel identifier. Detailed description for each component is included. The architecture is implemented in chip and also confirmed its performance on the test board mounting the chip. Test results show that the proposed 5-tap PRML architecture is well operated, and less than $2{\times}10^{-4}$ of BER (Bit Error Rate) is achieved with radial and tangential tilt margin of ${\pm}0.6^{\circ}$ on self-made 30GB BD at 1x speed.

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HEV용 중대형 2차전지 충전기 설계 및 해석 (Design and Analysis of Large Capacity Lithium Polymer Battery Charger for Hybrid Electrical Vehicle)

  • 오동섭;오성업;성세진;최재동
    • 전력전자학회:학술대회논문집
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    • 전력전자학회 2004년도 전력전자학술대회 논문집(1)
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    • pp.87-91
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    • 2004
  • In this paper, the paralleled forward converter, that is generally used as the power supply for the low voltage, high current load, is described. The proposed forward converter for battery charging could be provided the power without failure not only in steady state but also in the transient period by the step load variation or the unexpected faults among the converter modules. Each converter nodule designed is operated alone with the self closed controller for the elevation of stability, performance, reliability, and maintainability. The frequency response of the designed converter module is analyzed, and the stability is confirmed in analytic method. And the experiments of the paralleled battery charger are carried out in steady state, in the step load variation.

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악안면기형의 술후변화 및 평가 (Evaluation on the Late Results of Operation on the Patients of Maxillofacial Deformities)

  • 김종원
    • 대한치과의사협회지
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    • 제22권12호통권187호
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    • pp.1043-1046
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    • 1984
  • The clinical and statistical evaluation on the patients of maxillofacial deformities who were operated by author were analyzed after several month or years or se. Pre and post operative cephalometric radiographs of 45 orthognathic surgery patients were compared. The post operative radiographs had been taken at least 9 month to several years. Measurements were made between constructed hard tissue and soft tissue points located on each before and after film tracing. The items studied and evaluated are as follows: 1) Classification and divid of patients 2) Operation technic adopted by operator. 3) Motives of patients for operation and their untowards. 4) Self satisfication of patients after operation. 5) Post operative changes of soft and hard tissue. 6) Side action during and after operation.

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Experimental Study on Adjustment of Inlet Nozzle Section to Flow Rate Variation for Darrieus-type Hydro-Turbine

  • Watanabe, Satoshi;Shimokawa, Kai;Furukawa, Akinori;Okuma, Kusuo;Matsushita, Daisuke
    • International Journal of Fluid Machinery and Systems
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    • 제5권1호
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    • pp.30-37
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    • 2012
  • A two dimensional Darrieus-type turbine has been proposed for the hydropower utilization of extra-low head less than 2m. In a practical use of Darrieus-type hydro-turbine, head and flow rate may be varied temporally and seasonally. Considering that the cost advantage is required for the low head hydro turbine system, the Darrieus turbine should be operated with high efficiency in the wider range of flow rate possibly by using an additional device with simpler mechanism. In the present paper, an adjustment of inlet nozzle section by lowering the inlet nozzle height is proposed to obtain the preferable inlet velocity in low flow rate conditions. Effects of resulting spanwise partial inlet flow are investigated. Finally, an effective modification of inlet nozzle height over flow rate variation is shown.

임대주택 입주자의 관리참여 방안 (A M anagement Scheme by Rexidents in Rental Apartments)

  • 박은규
    • 한국주거학회:학술대회논문집
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    • 한국주거학회 1994년도 학술발표대회논문집 하
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    • pp.43-49
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    • 1994
  • In Korea, the rental apartments for low-income bracket have greatly been built and are being built now. But their management system is quite unstable and the residents' participation in the management is excluded throughly from the beginning. As a result, there are increasing complaints about their low quality of management as well as a self-righteous managerial behavior by the housing company. Therefore, it is required to be managed by residents in the rental apartmenr and especially the organization of management, such as decision making-executing-audition body, should be operated by the residents. To achieve this purpose, the management law should be consolidated into one and the method o imposing the expenses of repairing and maintenance should be improved by The Ministry of Construction and Transportation.

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Implementation of Low-Voltage Operation of Pentacene Thin Film Transistors using a self-grown metal-oxide as gate dielectric

  • Kim, Kang-Dae;Song, Chung-Kun
    • 한국정보디스플레이학회:학술대회논문집
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    • 한국정보디스플레이학회 2006년도 6th International Meeting on Information Display
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    • pp.190-193
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    • 2006
  • we implemented pentacene TFTs able to operate at low voltage less than 2V by using ultrathin Al2O3 layer as a gate insulator. The OTFTs exhibited a mobility of $0.27{\pm}0.05\;cm^2/Vs$, an outstanding subthreshold slope of $0.109{\pm}0.027$, and an on/off current ratio of $2.87{\pm}1.07{\times}10^4$. OTFT operated at low voltage, producing 3.5uA at $V_GS$= 2V and $V_DS$= 1.5V.

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대학정보시스템의 도입성과에 영향을 미치는 요인에 관한 연구

  • 강문석;정영수;정철호
    • 한국데이타베이스학회:학술대회논문집
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    • 한국데이타베이스학회 2010년도 춘계국제학술대회
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    • pp.65-74
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    • 2010
  • Most university has provided the information system that fit with their university peculiarity only, but there is not proper evaluation on the user satisfaction by that. In this study, first of all, it analysed which factors give satisfaction to the users when university operated the information systems and inquired the needed outcome variables in order to operate successful university information system. Through the inquisition of fitting supposition, we got something that organizational support and computer self efficacy which is personal factors were effected as an affirmative side to make a user satisfactions of information system. In more detail, organizational support and personal factors effected as an affirmative side to the quality of information system. And, so the quality of information system was influenced to user satisfaction that it raised the work result and increased the work products in organization through personal outcomes.

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