• Title/Summary/Keyword: Area standards

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

  • Choe, Yong-Mun;Park, Gyeong-Am;Cha, Ji-Seon;Choe, Hae-Man;Yun, Bok-Hyeon
    • Transactions of the Korean Society of Mechanical Engineers B
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    • v.24 no.11
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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.

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

  • Cho, Young-Jae;Yun, Jeong-Mi;Han, Seung-seok;Jo, Seoung-Hyun
    • Journal of Korean Society of Rural Planning
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    • v.29 no.4
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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'.

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

  • Jin, Heui-Chae
    • Journal of Korean Society for Geospatial Information Science
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    • v.3 no.2 s.6
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    • pp.83-90
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    • 1995
  • The standardization of NGIS emerges as an important subject because of the needs for sharing information and assuring of information inter-operability. The standardization could be developed by refering OSE/RM, which is promoted internationally, that the corresponding national standards are required. The standardization of NGIS, that has been promoting, consists of standardization of national electronic base-map and common data exchange format. The process for standardization of base-map has been taken in the area of feature-attribute code and data modeling. In the area of common data exchange format, we have been accepted the accommodation of international standards as the national standard.

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

  • Lee, Dhong-Ha
    • Journal of the Ergonomics Society of Korea
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    • v.30 no.1
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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.

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

  • Jeong, Woo-Gon
    • Journal of the Korean housing association
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    • v.23 no.5
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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.

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

  • Song, Byung-joon;Cho, Jin-il
    • The Journal of Sustainable Design and Educational Environment Research
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    • v.7 no.1
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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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A Study on the Planning Standards of Parks and Open Space Planning (택지개발사업지구의 공원녹지계획 지표연구)

  • 김귀곤;성현찬;황기현
    • Journal of the Korean Institute of Landscape Architecture
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    • v.22 no.1
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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
    • Journal of the Korean Society for Nondestructive Testing
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    • v.32 no.3
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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.

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

  • Yoo Tae-Myung
    • Journal of Korean Home Economics Education Association
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    • v.18 no.2 s.40
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    • pp.79-95
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    • 2006
  • This study was based on the conceptual framework of Home Economics curriculum development carried by Korean Institution of Curriculum and Instruction. The purpose of this study was to develop the educational objectives and content standards for family life area In home economics education. To achieve this, literature review and need assessment on curriculum contents for family life were performed, and expert group meeting and workshop were held. The results form various meetings and workshop were reflected in developing educational objectives and content standards. The educational objectives were developed in both general and specific levels. Content standards were developed according to educational objectives in specific level and major concepts for each content standard were proposed. The curriculum materials proposed in this study can be considered as a precious research for the upcoming future development of national curriculum and textbooks.

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

  • Kim, Jun-Gyu;Ryu, Jung-Rim;Choo, Seung-Yeon
    • Journal of the Korean housing association
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    • v.24 no.2
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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.