• Title/Summary/Keyword: class room

Search Result 300, Processing Time 0.025 seconds

Water Tests of Fuel Pump for 75-ton Class Liquid Rocket Engine (75톤급 액체로켓엔진용 연료펌프의 수류시험)

  • Kim, Dae-Jin;Choi, Chang-Ho;Hong, Soon-Sam;Kwak, Hyun-D.;Kim, Jin-Han
    • The KSFM Journal of Fluid Machinery
    • /
    • v.14 no.1
    • /
    • pp.61-65
    • /
    • 2011
  • A series of water tests of a fuel pump for liquid rocket engines are performed at a room temperature. According to the test results, the head coefficient of the pump follows the conventional similarity rule - unlike this, the pump shows better efficiency with higher rotational speed. Also, it is found that the pressure at the rear bearing outlet is higher than expected because the inlet of bypass pipe line is narrow. Furthermore, the cavitation performance of the fuel pump is found to be sufficient for the engine operation and is better at the lower flow ratio and higher rotational speed.

Stability Improvement of the Ultra-High Speed Micro Turbocharger Supported by Air Foil Bearings (공기 포일 베어링으로 지지되는 초고속 마이크로 터보차져의 구동 안정성 향상에 관한 연구)

  • Kwak, Yong-Suk;Kim, Chang-Ho;Chung, Jin-Taek;Lee, Yong-Bok
    • Transactions of the Korean Society of Mechanical Engineers A
    • /
    • v.32 no.7
    • /
    • pp.541-548
    • /
    • 2008
  • To improve the operational stability of the 100 Watts class Micro Gas Turbine, the air foil bearing with additional damping material has been investigated. The key of structure is that a viscoelastic material is coated under the top foil. The compliant foil journal bearing and thrust bearing are designed to withstand high load of vibrations at the operational speed 870,000 rpm. Test is executed in room temperature. Rotor has stably operated above 480,000 rpm. It is over 55% of the designed speed 870,000 rpm. Synchronous and subsynchronous vibrations are both well controlled. Vibration amplitude diminished over 50%. With the help of increased damping resulting from the viscoelasticity, the rotor stability of Micro turbocharger has been improved.

An Analysis of Factors in Class Room Design Based on Human Engineering (교육시설(敎育施設)의 인간공학적(人間工學的) 분석준거(分析準據))

  • Han, Eun-Sook
    • Journal of the Korean Institute of Educational Facilities
    • /
    • v.2 no.2
    • /
    • pp.41-50
    • /
    • 1995
  • The large increase in the number of students and the current rapid social change requires the expansion of educational facilities for the improvement of the educational content and its method, the usefulness of educational media, and the improvement of teaching and learning activities. The educational facilities have largely served is done efficiently and it results in a functional harmony of these two aspects. In order to maximize this harmony, and thus maximize the efficiency of school education, we must analyze the human engineering factors of educational facilities through human being that is the main subject of education, humans. Therefore to maximize the efficiency of school education, we must analyze the human engineering factors of educational facilities through human being that is the main subject in learning and living. In Conclusion we suggest the following six analying standards on human engineering of educational facilities; 1. adequacy 2. suitability 3. healthfulness 4. safety 5. beauty 6. modernity.

  • PDF

A Study on the Homemakers' Housing Notion according to Unit Size in Apartment - focus on 20pyung∼50pyung - (공동주택 평형별 주부들의 주거관에 관한 조사연구 - 20평형대∼50평형대를 중심으로 -)

  • 장경수;김경순
    • Korean Institute of Interior Design Journal
    • /
    • no.38
    • /
    • pp.116-124
    • /
    • 2003
  • The purpose of this study was provide basic data for homemakers' housing notion according to unit size in apartment. This study was conducted by questionnaires that concerning about middle class homemakers whom they lived in Bundang. The results of this study were as follows; 1) In research on the homemakers' general quality, 20pyung unit size was alike 30pyung unit size and 40pyung unit size was similar to 50pyung unit size. 2) Homemakers' perception according to unit size in apartment was various; (a) 20pyungㆍ30pyung unit size-effective household space for husbands' participation, more sports facilities, parking lot space etc. (b) 40pyungㆍ50pyung unit size-homemakers' individual room, ordering and variable unit plan etc. 3) In research on the homemakers' needs, each of unit size was analogous to storage, common facility, new design and new housing form etc.

Standardization of Cautious blasting (정밀발파의 표준화(下))

  • Huh, Ginn
    • Journal of the Korean Professional Engineers Association
    • /
    • v.23 no.6
    • /
    • pp.41-46
    • /
    • 1990
  • First of all, Under given condition such as bit gage of 36mm Drill bit with right class of jack-logs experimental test carried out from two face of Bench, firing of each hole brought 90 degree Angle face and them measured length of Burden and charged ammount of powder as following. (equation omitted) A=Activated Area A=ndi=m S=Peripheral length of Charged. room Ca=Rock Coeffiecency d : di=Hole diameter When constructed subway of Seoul in 1980 the blasting works increased complaint of ground vibration. in order to prevent the damage to structures. Some empirical equations were made as follows on condition with Jackleg Drill (Bit Gage ø 36mm) and within 30 meter distance between blasting site and structures. V=K(D / W)$\^$-n/ N=1.60-1.78 K=48-138 Project one of contineous works to above a determination of empirical equation on the cautious blasting vibration with Crawler Drill(ø 70-75mm) in long distance. V=41(equation omitted) V=124(equation omitted).

  • PDF

Instrumentation and Control Systems for Nuclear Power Plants (뉴스초점 - 원자력 발전소 계측제어 시스템)

  • Koo, In-Soo
    • Journal of the Korean Professional Engineers Association
    • /
    • v.43 no.2
    • /
    • pp.45-52
    • /
    • 2010
  • At the end of last year, Korean nuclear power plants, APR-1400 and a research reactor have been contracted to build plants at United Arab Emirates and Jordan. Since 1959, a historical background of nuclear technologies in Korea is summarized. The safety requirements for Instrumentation and Control (I&C) systems in Nuclear Power Plants (NPP) are discussed. Specific descriptions on the typical safety classification of I&C systems, the definitions of the electrical class 1E and the countermeasures against common caused failures are provided. And summaries of typical I&C systems such as the protection systems, the control systems, the instrumentations, the monitoring systems and a control room in NPP are introduced. Strict requirements on the development of the digital computer systems in nuclear applications are described.

  • PDF

A Study on an Evaluation Method for Human/System Interface of Advanced Supervisory Control Systems in Nuclear Power Plant (신형 원자력발전소 감시제어체계의 인간/체계 인터페이스 평가 방법에 관한 연구)

  • Lee, Dong-Ha;Im, Hyeon-Gyo;Jeong, Byeong-Yong
    • Journal of the Ergonomics Society of Korea
    • /
    • v.18 no.3
    • /
    • pp.153-169
    • /
    • 1999
  • The design of nuclear control room is advancing toward totally computer based human system interfaces (HSI). Computer based interfaces offer the opportunity to provide improved support of operator performance, but if not properly deployed, can introduce new challenges. This paper reviews the Westinghouse AP-600 Human Factors Verification and Validation Plan selected for HSI evaluation model of Korea next generation nuclear control rooms. The AP-600 HSI evaluation model addressed 15 evaluation issues considering major activity class of operator and task complexity factors. This paper also describes the test procedures experimenters should follow to evaluate the addressed issues.

  • PDF

An Architectural Proposal of Nursing Home by Remodeling a Closed School (폐교의 리모델링을 통한 유료노인전문요양시설 건축제안)

  • Moon Chang-Ho;An Jong-Lak
    • Journal of the Korean housing association
    • /
    • v.16 no.5
    • /
    • pp.83-90
    • /
    • 2005
  • This study aimed to examine the possibility of remodeled nursing home utilizing a closed school in Kunsan, where the number of closed schools increases and the ratio of elderly population grows. Major contents of research were understanding architectural characteristics of closed school and elderly housing in the sample area, and a suggestion of remodeling a closed school into nursing home. Conclusions can be summarized as follows; understanding the high ratio of elderly population and increases of closed schools in sample area, verification of overall possibility in remodeling a closed school into elderly facility, confirmation of availability in changing regular class room to residential rooms, and some proposals of principal points in floor planning - homelike atmosphere by small scaled residential units(10 persons), spatial hierarchy for residents' mental comfort, sliding door for accessibility, kitchen and dining space in residential unit for the residents' participation in houseworks.

Analysis on the Architectural Characteristics of Super High Rise Apartments (초고층 공동주택의 건축적 특성 분석)

  • Park, Hyeon-Ku;Song, Hyuk;Go, Seong-Seok
    • Journal of the Korean housing association
    • /
    • v.18 no.1
    • /
    • pp.11-18
    • /
    • 2007
  • At the economical crisis of Korea in 1997, self-determined price for apartment and the revision increasing the ratio of residential area for mixed-use residential building were introduced to activate the construction industry, which causes construction companies to build super high rise apartment discriminative and high class orientated. This study aims to classify the super high rise building which is planned to build or built recently and to analyze the architectural characteristics. The objects are 288 unit households in 26 apartment complexes higher than twenty five story since 1998. As a result, super high rise building comparing with existing apartments were being varied in plan types of main building and unit household and in construction types. As for the plan, the number of walls having opening to outdoor were increased and it is considered that high rise building can take advantage of a view, lighting and sunshine. The location of living room that used to be in the center of unit in existing apartment was moved freely without rule.

A Study on the High Temperature Characteristics of LDMOSFET under various Gate Length (Gate length에 따른 LDMOS 전력 소자의 고온동작 특성연구)

  • Park, Jae-Hyoung;Koo, Yong-Seo;Koo, Jin-Gun;An, Chul
    • Proceedings of the IEEK Conference
    • /
    • 2002.06b
    • /
    • pp.13-16
    • /
    • 2002
  • In this study, the electrical characteristics of 100v-Class LDMOSFET for high temperature applicat -ions such as electronic control systems of automo -biles and motor driver were investigated. Measurement data are taken over wide range of temperature(300k-SOOK) and various gate length(1.5 #m-3.0#m, step 0.3). In high temperature condition(>500k), drain current decreased over 30%, and specific on- resistance increased about three times in comparison with room temperature. Moreover, the ratio ROJBV, a figure of merit of the device, increased with increasing temperature.

  • PDF