• Title/Summary/Keyword: Design Height

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Numerical Optimization of Heat Transfer Surfaces with Staggered Ribs (엇갈린 리브가 부착된 열전달면의 수치최적설계)

  • Kim, Hong-Min;Kim, Kwang-Yong
    • Proceedings of the KSME Conference
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    • 2003.11a
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    • pp.735-740
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    • 2003
  • In this study, a numerical optimization to find the optimal shape of streamwise periodic ribs mounted on both of the principal walls is performed to enhance turbulent heat transfer in a rectangular channel. The optimization is based on Navier-Stokes analysis of flow and heat transfer with $k-{\varepsilon}$ turbulence model and is implemented using response surface method. The width-to-height ratio of a rib, rib height-to-channel height ratio, rib pitch to rib height ratio and distance between opposite ribs to rib height ratio are chosen as design variables. The object function is defined as a function of heat transfer coefficient and friction drag coefficient with weighting factor. Optimum shapes of the rib have been investigated for the range of 0.0 to 0.1 of weighting factor.

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Ergonomic Studies of Arm Shapes and Sleeves : Arm length depending on Arm movements (상지 형태와 의복소매에 관한 인간 공학적 연구(제2보) - 동작에 의한 상지 길이 변화 -)

  • Jo, Gyeong-Ae
    • Journal of the Ergonomics Society of Korea
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    • v.18 no.1
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    • pp.91-108
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    • 1999
  • In our previous work using a motion analyzer and 3-dimensional sonic digitizer, the arm shapes for 23 women in their early twenties were classified into three characteristic types. In order to design sleeves, suitable for arm movements for the three characteristic arm shapes, a relationship between arm length variation and shoulder/elbow angles has been investigated for four cases of arm movements (flexion, extension, adduction and abduction). Each arm movement can be characterized by the changes in shoulder angle and the changes in elbow angle at the maximal shoulder angle. In all the four cases of arm movements, the changes of shoulder length and cap height are largest at the maximal shoulder angle. These changes were little affected by changes in elbow angle. The changes in the lower arm length and the difference between cap height and upper arm length are the largest at the maximal elbow angle of the maximal shoulder angle. There is a linear relationship between cap height and shoulder angle during arm movements; thus, in designing sleeves the cap height can be determined from the regression of cap height vs. shoulder angle.

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Improvement plan for the standard for calculating the height of the stair railing for Barrier Free (BF) certification system (장애물 없는 생활환경(BF) 인증제도 계단 난간 높이 산정기준 개선안)

  • Lee, Sang-Soo;Bang, Hong-Soon;Kim, Ok-Kyue
    • Proceedings of the Korean Institute of Building Construction Conference
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    • 2022.04a
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    • pp.218-219
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    • 2022
  • Among the Barrier Free (BF) certification evaluation items for public facilities, at which position the standard for the effective height of the stair railing handle should be calculated is not clearly determined. Because of this, not only the evaluation standards of the certification authority and the evaluation committee are different, but disputes are occurring between the ordering organization, the design company, and the construction company. Therefore, the stair railing installation standard laws for public facilities were analyzed and through a case study of institutions that obtained the BF certification, problems were analyzed. The results of problem analysis reveal the following. 1) The standards of the Ministry of Health and Welfare and the Ministry of Land, Infrastructure, and Transport were different. 2) The effective height calculation standard was ambiguous, and disputes occurred frequently. To solve this problem, we proposed improvement plans for calculating the height of the stair railing that can comply with laws while ensuring safety.

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A Study on the Architectural Design Characteristics of the Plan and the Structure in Sudeok Temple's Daeung-Jean (건축설계 측면에서 본 수덕사 대웅전의 평면과 가구 특성에 관한 연구)

  • Kim, Do-Kyoung
    • Journal of architectural history
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    • v.17 no.4
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    • pp.97-112
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    • 2008
  • In this study, I attempted to the architectural design characteristics of Daeung-Jeon in Sudeok Temple. For this purpose, After I set up several assumptions in the basis of the general characteristics of Korean wood architecture, and then, analyzed floor plan, structural formation and section sizes of structure and bracket members in relation to module and unit. As the results, the characteristics of the design process of plan and structure are follows. (1) 1 ja(尺), the unit applied to this building is measured $307.6{\sim}318.3mm$) and the average is 312.9mm (2) It is estimated that the floor plan designed on the basis of the top of columns. By the applied unit, every bay of the front side and the side is each designed by 15 ja and 8.5 ja. (3) The section is composed of piled members which have same section size. As basic module of section size called 'jae(재;材)', it is estimated at width 0.45 ja by height 0.75 ja. And as the secondary module, height between jae and is called 'gyoe(계;)' and it wes designed by three height size of 0.25 ja, 0.27 ja and 0.30 ja, (4) It is estimated that the section plan was designed by the order as follows. Firstly, the horizontal position of purlins wes decided on the basis of the intersection point of long and short rafters, and then the position and the section size of purlins and jangheyo(長舌) wes decided on the basis of the slope of roof and rafters. Secondly, going down from purlins, the members of structure composed of 'jae' and 'gyoe' was repeated. Lastly, for the purpose of linking the structure members located on the center line of adjacent purlins organically, the height of whaban(화반) was controlled.

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Independence and Homogeneity Tests of the Annual Maxima Data used to Estimate the Design Wave Height (설계파고 추정에 사용한 연 최대 자료의 독립 및 분포 동질 검정)

  • Cho, Hong Yeon;Jeong, Weon Mu;Back, Jong Dai
    • Journal of Korean Society of Coastal and Ocean Engineers
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    • v.32 no.1
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    • pp.26-38
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    • 2020
  • A statistical test was carried out on the IID (Independently and Identically Distributed) assumption of the AM (Annual Maxima) data used to estimate the design wave height. The test was divided into independence (randomness) test and homogeneity test, and each test was conducted on AM data of 210 and 310 stations in coastal and inner coastal grids in typhoon and non-typhoon (monsoon) conditions. As a result of the independence test, the rejection ratios of the test are in the range of 1.8~5.3% and 1.4~6.0% for the non-typhoon and typhoon data sets, respectively. On the other hand, in the distribution difference test of typhoon data and nontyphoon data, the same distribution hypothesis was found to be rejected in the range of 47~79% according to the test method for both coastal grid and inner coastal grid. Therefore, in estimating design wave height by extreme value analysis, the estimation process by dividing the typhoon and non-typhoon data is appropriate.

Derivation of Optimal Design Variables Considering Carbon Monoxide Emission Characteristics of Commercial Gas Stove Burners (업소용 가스레인지 버너의 일산화탄소 배출 특성을 고려한 최적 설계변수 도출)

  • Il Kon Kim;Taehoon Kim
    • Journal of the Korean Society of Safety
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    • v.39 no.1
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    • pp.1-8
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    • 2024
  • Commercial gas stoves feed primary air to the burner and burn the fuel-air mixture in a partially premixed combustion. This mechanism produces carbon monoxide during combustion. In this study, design parameters of a commercial gas stove were optimized by considering the carbon monoxide emission. Gas consumption rate, carbon monoxide emission, and water boiling temperature as a heating performance were determined. Carbon monoxide emission was measured using a Korean Industrial Standards standard collector. Water boiling temperature was measured by first soaking the pot in water for approximately 10 min and then heating the pot filled with water. A thermocouple was installed inside the pot. Carbon monoxide increased as the nozzle diameter was increased and the burner-pot height was decreased. This result was due to the insufficient mixing between the fuel and air. Heating performance was enhanced when the nozzle diameter was increased and the burner-pot height was decreased. However, the heating performance deteriorated when the nozzle diameter was 1.8 mm and the burner-pot height was reduced to 50 mm. This phenomenon was due to the formation of a flame on the side of the pot. A merit factor was defined to find the optimal design parameters to satisfy gas consumption rate, carbon monoxide emission, and heating performance. Optimal design values were established to be a nozzle diameter of 1.5 mm and a burner-pot height of 60 mm.

A Study on the Design Optimization of Corner Pprotection for LNG Storage Tank (LNG저장탱크 코너프로텍션의 설계 최적화에 관한 연구)

  • Kim, Hyung-Sik;Hong, Seong-Ho;Seo, Heung-Seok
    • Transactions of the Korean Society of Mechanical Engineers A
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    • v.28 no.9
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    • pp.1384-1390
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    • 2004
  • The full containment Liquefied Natural Gas(LNG) storage tank is based on a double liquid container concept : two separate containers, one within the other, are capable of containing the LNG. The outer concrete tank provides comer protection(secondary containment) to withstand and safely contain any spill from the inner tank. The comer protection is installed on inside corner surface of outer concrete tank. Because of high and complex stresses, corner protection is designed by ASME section ⅧI Div. 2, Appendix 4 on behalf of API 620 which is main design code for LNG tank. Design guidelines to determine design factors such as liner thickness and knuckle radius are not well understood because Appendix 4 is the design method not based on equation but FEM. Recently, the volume of LNG tank shows a tendency to increase. So it is necessary to set up the design guidelines to cope with change of LNG tank capacity and height/diameter ratio. In this paper, optimum design of corner protection was performed and the design guidelines were suggested by the results of FEM for LNG tanks which have different capacities and height/diameter ratio.

Survey on the Dimension of the Bathroom Equipment for the Korean Elderly (한국 노인에게 적정한 욕실설비 치수에 대한 실험 조사)

  • Ju Seo-Ryeung;Lee Ji-Ye;Kim Min-Kyoung
    • Journal of the Korean housing association
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    • v.17 no.1
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    • pp.165-176
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    • 2006
  • In the design guideline about the existing elderly housing, the equipment related to bathroom are the most important in the secure and functional aspect. On the other hand, the present elderly housing is being designed according to foreign design guideline or common housing form instead of reflecting living and physical qualities of the Korean elderly. Therefore, in this study based on the guideline of the existing literature, we made Mockup furnished with the equipments of bathroom and conducted an experiment in finding proper position and height for Korean elderly enough to use the bathroom conveniently and independently. The equipments of bathroom consist of different height wash bowls, toilet stools, grab bars, and a bathtub. As a result, suitable height of wash bowl is 760 mm $\pm{\alpha}$. We can realized that elderly feel comfortable to grab perpendicular bars of toilet stools more than horizontal ones. So it is necessary for elderly to grip perpendicular of grab bars added to prevention slipping and made shape easy to hold. Most of elderly told us that 500 mm of the bathtub setting is suitable. But many other people feel high. So height of the bathtub must be established lower than 500 mm for safety in the bathroom and for convenience.

Study on Body Proportion Using Body Indexes of Mongolian Men and Women in 20's (몽골 20대 남녀의 지수치를 이용한 인체 프로포션 연구)

  • Im, Soon
    • Journal of the Korea Fashion and Costume Design Association
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    • v.14 no.2
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    • pp.89-100
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    • 2012
  • The purpose of this research is to compare the body proportion of the Mongolian and Korean men and women in their 20' s by comparing the characteristics of the body type that uses the body indexes, in order to provide the base data for the increased fit of the apparels. The results are as follows. 1) Histogram of the Rohrer' s Index for the Mongolian men and women in their 20s was examined. the Mongolian men, normal body type took up 48.0% while small body type comprised 50.0% and obese body type comprised 2.0%. the Mongolian women, normal body type comprised 61.5%, small body type comprised 22.1% and obese body type comprised 16.4%. 2) The body proportion of Korean men has 1:1.62 with upper body and low body part on a waist basis, and Mongolian men has 1:1.65. Thus Mongolian men has longer pan of lower body than Korean men. 3) Mongolian women has longer part of lower body and has higher rates of hip height, crotch height, knee height than Korean women. Mongolian women has high rate of hip line and calf length. 4) As a result comparison using the body index of Mongolian and Korean women (bust thickness/ bust width, waist thickness / waist width, hip thickness / hip width, when regarding the height as 100 ), it was found that Mongolian women are flatter than korean women.

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Effect of the building envelope on heating and cooling load in super tall building considering the meteorological changes with height (높이별 기상변화를 고려한 초고층 건축물의 외피종류별 냉난방 부하특성 분석)

  • Choi, Jong-Kyu;Kim, Yang-Soo;Song, Doo-Sam
    • 한국태양에너지학회:학술대회논문집
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    • 2012.03a
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    • pp.337-344
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    • 2012
  • Today, the number of super tall buildings are under construction or being planed in Middle East and Asian Countries. For example the burj Khalifa, the tallest building in the world, is completed in 2008 and the height of that is about 800m. Also, Lotte World Tower is under construction in Korea. External environmental conditions such as wind speed, air temperature, humidity and solar radiation around the super tall building differs according to the building height due to the vertical micro climate change. However, the meteorological information used for AC design of building is obtained typically from standard surface meterological station data(~2m above the ground). In this paper the effect of the building envelope on heating and cooling load in super tall building considering the meteorological changes with height was analyzed with simulation method. As results of this research, the guideline to select the building envelop alternatives for super tall building will be suggested in this paper.

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