• Title/Summary/Keyword: Area standards

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음속 노즐의 임계 압력비에 대한 저 레이놀즈수의 영향 (Evaluation of Critical Pressure Ratios Sonic Nozzle at Low Reynolds Numbers)

  • 최용문;박경암;차지선;최해만;윤복현
    • 대한기계학회논문집B
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    • 제24권11호
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    • pp.1535-1539
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    • 2000
  • A sonic nozzle is used as a reference flow meter in the area of gas flow rate measurement. The critical pressure ratio of sonic nozzle is an important factor in maintaining its operating condition. ISO9300 suggested the critical pressure ratio of sonic nozzle as a function of area ratio. In this study, 13 sonic nozzles were made by the design of ISC9300 with different half diffuser angles of 2。 to 8。 and throat diameters of 0.28 to 4.48 mm. The test results of half diffuser angles below 8。 ar quite similar to those of ISO9300. On the other hand, the critical pressure ratio for the nozzle of 8。 decreases by 5.5% in comparison with ISO9300. However, ISO9300 does not predict the critical pressure ratio at lower Reynolds numbers than 10(sup)5. Therefore, it is found that it is a better way for the flow of low Reynolds number to express the critical pressure ratio of sonic nozzle as a function of Reynolds number than area ratios. A correlation equation of critical pressure is introduced with uncertainty $\pm$3.2 % at 95% confidence level.

정주계층별 농촌생활서비스 기능정립 및 취약지역 기준에 관한 연구 (A Study on Establishment of Rural Living Service Functions by Settlement Class)

  • 조영재;윤정미;한승석;조승현
    • 농촌계획
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    • 제29권4호
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    • pp.13-26
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    • 2023
  • Recently, South Korea has prepared laws and systems to systematically manage rural spaces in response to the era of population decline and is making various efforts to promote related policies. However, various basic studies that can support this are still insufficient. In particular, in this study, the functions and roles of each settlement class were established along with the classification of the sedentary classes in rural areas, and the classification system for rural living services was established, and the hierarchy by functional facilities and the minimum standards for vulnerable areas (accessibility) were established. Specifically, in this study, the settlement class was divided into 4 classes of "central area - midpoint area - small point area - hinterland", and each function and role was presented, and the rural living service classification system was finally reestablished as 10 sectors and 31 functional facilities. In addition, the hierarchy and accessibility standards of rural living service functional facilities was set within 5 to 15 minutes for 'lower and basic services', within 10 to 20 minutes for 'medium and basic services', within 15 to 30 minutes for 'intermediate and complex services', within 20 to 60 minutes for 'high car/complex service' and within 10 minutes for 'urgent service'.

개방형 환경과 국가지리정보체계(NGIS) 표준화 (A study on the Open System Environment and NGIS Standards)

  • 진희채
    • 대한공간정보학회지
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    • 제3권2호
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    • pp.83-90
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    • 1995
  • 국가지리정보체계의 표준화는 정보의 공동활용 및 상호운용성의 확보 등을 이유로 중요한 존재로 부과되고 있다. 이의 표준화는 현재 구체적으로 추진되고 있는 현재 국제적으로 추진되고 있는 OSE/RM을 참조하여 발전할 수 있으며 이의 구조에 맞는 국가 표준의 제정이 요구된다. 현재 추진하고 있는 국가지리정보체계 표준화는 국가 기본도 표준화와 공통데이터교환포맷 표준화가 있으며 국가 기본도 표준화에서는 지형지물 코드 및 속성 부분데이타 모델링 등을 추진하고 있고 공통데이터교환포맷 표준화에서는 국외표준의 국내수용으로 그 기본 방향을 유지하고 있다.

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제어실의 인적오류 예방에 적용 가능한 ISO 표준 검토 (A Review on ISO Standards Applicable for a Human Error Tolerant Control Center Design)

  • 이동하
    • 대한인간공학회지
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    • 제30권1호
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    • pp.161-168
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    • 2011
  • Objective: The aim of this study is to review the ISO(the International Organization for Standardization) standards recommendations on a human error tolerant control room design. Background: ISO TC(Technical Committee) 159 published a variety of international standards on design of mental and physical work, design of displays and controls, and workstation layout design. A proper edition of these standards can be a good resource for a human error tolerant control center design guidelines. Method: Recommendations of ISO TC 159 standards were grouped into arrangement of control suite, layout of control room, layout and dimensions of workstations, design of displays and controls, environmental design, alarm, automation, management system design, procedure and training. Results: It was found that some standards on the design of supervisory control and data acquisition(SCADA), alarm, automation, layout, workload management, and environment can be used for human error prevention guidelines in the control center design. Conclusion: ISO TC 159 standards were not sufficient to cover all the ergonomics area of control center design. Application: Designers can have technical aids from these ISO standards to improve ergonomic performance of their control center.

개발권양도제 적용방안에 관한 연구 - 광주광역시 주거지를 중심으로 - (A Study on Application Methods of the Transfer of Development Rights - Focused on Residential Areas of Gwangju -)

  • 정우곤
    • 한국주거학회논문집
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    • 제23권5호
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    • pp.61-73
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    • 2012
  • This study applied the value of floor-area-ratio standard calculation method to case areas and analyzed them to overcome the limits of previous studies in calculation methods for area standards and land price (value) standard development rights. The results are presented as follows: First, criteria to select sending areas and receiving areas are needed. Second, calculation methods based on the value of floor-area-ratio standard can be widely used as standardized criteria in various areas. Third, for the connection of sending areas with receiving areas, the connections of 1:1, n:1, 1:n, and n:n are available and the location of possible dealing areas should be considered. Also, the choice of connecting unions that meet the purpose of TDR presented by local governments is available. Fourth, for Gwangju, as receiving areas downtown provide higher profits than previous renewal projects, the application of TDR is available. Application methods to overcome problems are presented as follows: First, criteria to select sending and receiving areas should be prepared and implemented in an order of priority. Second, in calculating development rights, methods based on the value of floor-area-ratio standard should be used. Third, the standards and principles of sending and receiving areas should be designated and possible dealing areas should not be limited.

친환경건축물인증학교의 생태환경요소에 대한 실태조사 (Survey of actual status of ecological environment elements of certification schools of environment friendly architecture)

  • 송병준;조진일
    • 교육녹색환경연구
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    • 제7권1호
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    • pp.39-55
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    • 2008
  • The purpose of this study is to suggest improvement of certification standards of environment friendly architecture in ecological environment field by surveying and analyzing actual status of actual certification schools of environment friendly architecture per ecological environment elements through extracting ecological environment elements which is possible to analyze in quantity certification standards of environment friendly architecture. As contents of the study, first, certification as an examination on certification system of environment friendly architecture, summary of certification system of environment friendly architecture, ecological environment elements which is possible for quantitative analysis of ecological environment certification standards were extracted. Second, actual status of ecological environment elements per school grade, region, and population increase by collecting actual data of certification schools of environment friendly architecture. Third, using analysis data of ecological environment elements, ecological area ratio of certification schools of environment friendly architecture per weighted values of space types was calculated and the results were analyzed as the follows. (1) In case of preliminary certification out of total objects of investigation schools was average 34.06% but in this case of certification, it was reduced to 33.07%. However, it is difficult to make judgment as actual evidence data since ecological area ratio of actual preliminary certification is data based on drawing planes. Therefore, in case of this certification, elementary schools was investigated at average 33.11%, middle schools 34.81%, and high schools 31.28% and middle school showed the highest relatively. (2) Besides, average composition ratio of ecological area ratio was 63.04% in case of this certification regardless of school grade and region and it was analyzed that about 70% of ecological area ratio is composed of the natural based green area including pure natural based green land and 6.89% of ecological learning institute.

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택지개발사업지구의 공원녹지계획 지표연구 (A Study on the Planning Standards of Parks and Open Space Planning)

  • 김귀곤;성현찬;황기현
    • 한국조경학회지
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    • 제22권1호
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    • pp.179-198
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    • 1994
  • Urban parks and open spaces provide the community residents with the most easily accessible source for outdoor recreation, contributing also to the improvement of quality of natural environment in urban area. The demands of urban residents' for more and better green area are ever-increasing. However, the level of most urban open spaces which are easily accessible for residents are not satisfactory to meet the residents' demand in availability and in quality as well. Most existing urban open spaces are simply built of green areas only or have been developed in almost identical design with little consideration for individual uniqueness of the site. When developing neighbourhood parks in urban housing complexes, for example, little consideration is being given to topographical conditions, interrelation with the adjacent green area, or viability of the urban ecosystem. In many cases, urban park development projects are being done with serious negligence of natural properties of the site, by even destroying existing healthy woodlands. for instance. The objectives of this study are; -To survey on the domestic and the overseas cases of regulatory systems, development status and planning methods for urban open space. -To identify underlying issues of residental park developments in urban housing projects and establish appropriate improvement measures thereof, by studing and analyzing current-use data of developed urban parks and management status thereof. -To establish improved standards for urban open space planning, by integrating above surveys and studies, and recommendation for revision of related legislation is also presented to implement these standards.

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Infrared Thermography Characterization of Defects in Seamless Pipes Using an Infrared Reflector

  • Park, Hee-Sang;Choi, Man-Yong;Park, Jeong-Hak;Lee, Jea-Jung;Kim, Won-Tae;Lee, Bo-Young
    • 비파괴검사학회지
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    • 제32권3호
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    • pp.284-290
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    • 2012
  • Infrared thermography uses infrared energy radiated from any objects above absolute zero temperature, and the range of its application has been constantly broadened. As one of the active test techniques detecting radiant energy generated when energy is applied to an object, ultrasound infrared thermography is a method of detecting defects through hot spots occurring at a defect area when 15~100 kHz of ultrasound is excited to an object. This technique is effective in detecting a wide range affected by ultrasound and vibration in real time. Especially, it is really effective when a defect area is minute. Therefore, this study conducted thermography through lock-in signal processing when an actual defect exists inside the austenite STS304 seamless pipe, which simulates thermal fatigue cracks in a nuclear power plant pipe. With ultrasound excited, this study could detect defects on the rear of a pipe by using an aluminium reflector. Besides, by regulating the angle of the aluminium reflector, this study could detect both front and rear defects as a single infrared thermography image.

가정과교육에서 "나와 가족생활" 영역의 교육목표와 내용체계 연구 (The Development of Educational Objectives and Systemization of Contents for 'Family Life' Area in Home Economics Education)

  • 유태명
    • 한국가정과교육학회지
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    • 제18권2호
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    • pp.79-95
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    • 2006
  • 이 연구는 가정과 교육과정 개발의 이론적 체계를 틀로 하고 선행 연구와 교육과정 동향의 분석, 교육내용 요구조사를 고려하여 $\ulcorner$나와 가족생활$\lrcorner$ 영역의 교육목표와 내용체계를 구안하였다. 개발된 시안은 전문가 협의와 워크숍을 통해 다양한 의견을 수렴하여 수정 보완하여 최종안을 구안하였다. $\ulcorner$나와 가족생활$\lrcorner$ 영역의 교육목표는 '나와 가족생활을 개인과 가족, 사회, 문화의 맥락에서 이해하고 나와 가족생활 중에 일어나는 실천적 문제를 해결하여 건강한 가족생활을 영위할 수 있다.'로 선정하였다. 개발된 내용체계를 요약하면 다음과 같다.

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국내 공동주택의 품질향상을 위한 BIM기반 면적산정 방법의 실효성 연구 (An Analysis on Effectiveness of BIM-based Area Calculation Method for Improving Quality of Korean Apartment Housing)

  • 김준규;류정림;추승연
    • 한국주거학회논문집
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    • 제24권2호
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    • pp.45-52
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    • 2013
  • The Purpose of this study is to improve construction quality with area calculation methods from BIM design technology. BIM has been supporting public-private-organizations and academic circles as a solution technology to manage and produce informations effectively from construction field including facility manage one. BIM standards are necessary but not sufficient for achieving perfect practical application in South Korea. In particular, development of architectural rule based area calculation methods is very urgent and important to improve construction quality. To solve those problems, methods and standards on area calculation are developed and its effectiveness of the proposed BIM-based methods is defined through the analysis between the existed area calculation method and process which are 2D based. This study will not only improve economic efficiency and accuracy of the construction quality but also settle the BIM environment in the domestic architecture.