• Title/Summary/Keyword: Covering materials

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Measurement and Comparison of Overall Heat Transfer Coefficients for Greenhouse Covering Materials with Thermal Screens (온실용 피복재 및 보온재의 관류열전달계수 측정 및 비교)

  • Diop, Souleymane;Lee, Jong Won;Lee, Hyun Woo
    • Journal of The Korean Society of Agricultural Engineers
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    • v.56 no.4
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    • pp.41-51
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    • 2014
  • 천공복사를 구현할 수 있는 관류열전달계수 측정용 실내실험장치를 제작하고 국내에서 사용되고 있는 온실 피복재 및 보온재의 관류열전달계수를 측정하여 실외실험에서 측정된 결과와 비교하여 타당성을 평가하였다. 외부피복은 0.1 mm 두께의 폴리에틸렌 필름을 사용하여 일중 및 이중피복으로 처리하였다. 이중외부피복조건의 경우 4가지 종류의 보온재를 처리하여 총 6가지 피복처리에 대하여 실험을 실시하였다. 모든 피복처리조건에 대하여 야간복사 유무에 따른 관류열전달계수 측정실험이 수행되었다. 천공복사의 유무에 따라 온실피복재의 관류열전달계수의 변화 경향이 크게 차이가 있었기 때문에 실내실험을 통해 관류열전달계수를 측정하기 위해서는 반드시 실제의 천공복사를 구현할 수 있는 실험장치가 필요할 것으로 판단된다. 실내 실험결과와 실외 실험결과가 비교적 잘 일치하였으며 실내실험장치를 이용하여 관류열전달계수를 측정하는 것이 타당성이 있음을 확인할 수 있었다. 천공복사 유무에 따른 관류열전달계수의 차이는 핫박스 내외부의 온도차이가 증가함에 따라 감소하는 것으로 나타났다.

Application Case of Test of Revegetation Measures on Design of Slopes Revegetation and Tentative Instruction on Construction Work -With a Case of Slopes Along the National Road Between Nongseo and Eomo - (비탈면 녹화 설계 및 시공 잠정 지침 적용사례 -농소어모구간 국도비탈면을 중심으로-)

  • Jeon, Gi-Seong
    • Journal of the Korean Society of Environmental Restoration Technology
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    • v.10 no.4
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    • pp.95-108
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    • 2007
  • Test application of revegetation measure was made on the roadside slope damaged by Nongseo-Eomo national road improvement project in a bid to prevent the soil from being washed out as well as to restore the ecological environment, and the survey for assessment of the effect of slope revegetation measures was conducted, beginning May 11 through Nov 7, 2006. In the wake of comprehensive reviewing and evaluating the surrounding topographic environment, physical and chemical characteristics of soil, germination of revegetation plants, analysis of bio mass, covering ratio and the plants appeared, measure b was found to have been most appropriate to cut blasting rock slope, and alternatively measure c. For cut ripping rock slope, measure c-1 appeared to be effective in revegetation effect, and alternatively, b-1.When it comes to cut soil slope, measure c-2 was found to be effective, and b-2 to be a good alternative. And for embankment soil slope, measure b-3 appeared to be most efficient in revegetation effect and measure f as alternative.

Molecular Screening for P53 Mutations among Tobacco Smokers in a Surveyof Awareness of Links between Tobacco, Alcohol Use and Cancer in Saudi Arabia

  • Alshammari, Fawaz D
    • Asian Pacific Journal of Cancer Prevention
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    • v.16 no.16
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    • pp.6845-6849
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    • 2015
  • Background: Roles of tobacco and alcohol use in etiology of cancer are well established. Alterationin in P53 have essential roles neoplastic change by preventing genome mutation; the aim of this study was to assess the association between P53 mutation and tobacco and alcohol consumption, as well as to assess the epidemiology of tobacco and alcohol use as risk factors for cancer in the adult population of northern Saudi civilians. Materials and Methods: A cross-sectional survey from October 2014 to January 2015, covering 3,398 adults, was performed. P53 mutation molecular detection was performed for 100 tobacco and alcohol users, usingDNA extracted from buccal cells. Results: Of the 3,398 participants 3,253/3398(95.7%) responded, with a male female ratio of 1.10: 1.00. Out of these, 24.8% had smoked tobacco in their lifetime and 2.7% were consumers of alcoholic beverages. None was identified with any P53 mutation. Conclusions: The prevalence of tobacco smoking among the northern Saudi civilians was relatively high. Females' attitudes in tobacco and alcohol related issues were found to be affected by social stigma. Tobacco and alcohol use has no link to P53 gene mutations.

Agronomic Characteristics as Affected by Polyethlene Film Mulching and Sowing Date in Vegetable Perilla (잎들깨 멀칭재배 및 파종기에 따른 생육특성)

  • 김동관;정찬식;천상욱;국용인;김명석;방극필
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.49 no.3
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    • pp.184-187
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    • 2004
  • In case of a semi-forcing culture for vegetable perilla, the following research results on the effect of black polyethylene mulching, the optimum sowing season, and the seedling stand improvement method were drawn. Soil temperature was higher and the emergence was faster in a black polyethylene mulching culture than in a non-mulching culture. However, the mature was late, the main stem were larger, and the seed yield, as well as the leaf yield, was greater in a mulching culture than in a non-mulching culture. Considering growth and chilling injury, the stable sowing season of vegetable perilla was judged to be the early in January. The covering materials for improvement of the seedling stand can be a non-woven fabric and hyaline polyethylene. However, the non-woven fabric seemed to be quite suitable in view of the stability and convenience of control after the emergence of perilla.

Deconstructive Features of Headdress Found in Jean Paul Gaultier's Collection (Jean Paul Gaultier 컬렉션에 나타난 헤드드레스의 해체적 특성)

  • Kim, Sun-Young
    • Journal of the Korean Society of Clothing and Textiles
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    • v.36 no.5
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    • pp.489-500
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    • 2012
  • This work surveys the trend and dissolution characteristics in headdress that appear in Jean Paul Gaultier's collection. Along with a related literature review, a total of 903 headdress pieces shown in collections 40 times (excluding the common caps and hats) were analyzed, covering from 2001S/S to 2010 F/W of Jean Paul Gaultier's Haute Couture and Pret-a-Porter. The headdress trend indicated in his collections was divided into such subgroup forms of folklore, usage of natural things, usage of artificial things, religion, retro, scarf, variations in headgear, mask and veil, atypical type and abstract. Such an expression tendency was so unique and mixed characteristic that it was hard to define its form and structure thanks to enlargement and exaggeration, extremity in ornaments, and use of foreign materials, which led to creative dynamics. Gaultier's headdress also reflected the following characteristics: first, expression of difference indicative of time deconstruction; second, uncertainty of meanings via deconstruction; third, text interactivity via deconstruction of gender and material adopted; fourth, decentralization through dissolution of the Orient and the Occident.

Contribution of Road Capital in Industry and Optimal Level of Road Capital in South Korea (한국 도로 자본의 산업에 대한 영향과 도로자본 스톡의 최적수준 분석)

  • Kook, Woo Kag
    • International Journal of Highway Engineering
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    • v.15 no.3
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    • pp.137-149
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    • 2013
  • PURPOSES: This study is to suggest the Contribution of Road Capital in Industry and Optimal Level of Road Investment in South Korea METHODS: Based on the literature review, This research is empirically estimated using disaggregate and disaggregated data composed of 10-sectors covering the entire korea economy for the period 1970~2000. The relevant policy questions addressed in this report are : cost reduction and Scale elasticities of road, effect of road capital stock on demand for labor, capital and materials, marginal effect of road, industry TFP growth decomposition, Net Social Rates of Returns, optimal of road capital. RESULTS : The marginal benefits of the road capital at the industry level were calculated using the estimated cost elasticities. Demand for the road capital services varies across industries as do the marginal effects. The marginal benefits are positive for the principal industries. This suggests that for these industries the existing stock of road capital may be under supplied. CONCLUSIONS: This results emerges is that the ratio of the optimum to actual road capital, measured by road, was high at beginning of the period 1970s and declined 1990s. There appears to be evidence of under-investment in road capital. That is continuous and premeditated investment for road which lead to saving time and finance.

A Study on Middle School Students' Interests in Housing Education Contents of Technology Home Economics Subject - Based on Jeonbuk Province - (중학생의 기술 가정교과 중 주생활 교육내용에 대한 흥미도 연구 - 전북지 역을 중심으로 -)

  • Kwark, Kyoung-Sook
    • Korean Journal of Human Ecology
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    • v.15 no.1
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    • pp.177-185
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    • 2006
  • The purpose of this study is to research middle school students' interests in the housing education contents of Technology Home Economics Subject - to classify the contents into three units, we have application of living space, indoor environment and equipments, support and repair of housing. This study has a subject of 529 middle schoolers living in Jeonbuk province. In this statistical analysis, SPSS program was utilized to analyze percentage, mean and standard deviation. These materials were also verified by t-test. The results of this research were as follows: Middle school students' interests in housing education contents stayed at a mid-level. There was a significant difference in contents interest according to their gender - boys appeared to have a higher interest than girls. On the basis of these results, it can be suggested that these results offer fundamental information for improving students' critical practice in their real life. Since this study has conducted a limited research with a topic of housing education only, it is essential that further research covering a wider array of themes be done in the future.

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Mechanical Properties of Steel-Fiber Reinforced Concrete (강섬유보강콘크리트의 역학적 거동 특성)

  • 홍성구;권숙국
    • Magazine of the Korean Society of Agricultural Engineers
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    • v.31 no.3
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    • pp.81-91
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    • 1989
  • The aims of this study were to determine mechanical properties of steel-fiber reinforced concrete under splitting tensile, flexural and compressive loading, and thus to improve the possible applications of concrete. The major factors experimentally investigated in this study were the fiber content and the length and the diameter of fibers. The major results obtained are summarized as follows : 1.The strength, strain, elastic modulus and energy obsorption capability of steel-fiber reinforced concrete under splitting tensile loading were significantly improved by increasing the fiber content or the aspect ratio. 2.The flexural strength, central deflection, and flexural toughness of steel4iber reinforced beams were significantly improved by increasing the fiber content or the aspect ratio. And flexural behavior characteristic was good at the aspect ratio of about 60 to 75. 3.The strength, strain, and energy absorption capability in compression were increased with the increase of the fiber content. These effects were not so sensitive to the aspect ratio. The energy absorption capability was improved only slightly with the increase of the fiber length. 4.The elastic modulus, transverse strains, and poisson's ratios in compression were not influenced by the fiber content. 5.The steel-fibers were considered to be appropriated as the materials covering the weakness of concrete because the mechanical properties of concrete in tension and flexure were significantly improved by steel-fiber reinforcement.

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A Study on the Analysis of the User's Degree of Satisfaction in Urban Pedestrian Sidewalk -Case Study of Urban Pedestrian Sidewalk in Taejon City- (도시가로 보행자 공간의 만족요인 분석에 관한 연구 -대전시 도시 가로 보행자 공간을 중심으로-)

  • 김대현
    • Journal of the Korean Institute of Landscape Architecture
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    • v.22 no.3
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    • pp.29-40
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    • 1994
  • The purpose of this study was to investigate factors and variables which have significant effects on satisfaction of urban pedestrian sidewalk in taejon city, and to suggest basic information for urban pedestrian sidewalk. These works consist of two phase; The first, tested the user's degree of satisfaction for 37 spots of pedestrian sidewalk slide and then selected 10 spots slide by the stratified random sampling method. The second, analyzed factors and variables of satisfaction of urban pedestrian sidewalk using the semantic differential scale method, and then processed by mean score, correlation, factor analysis, multiful algorithm. The results were summarized as follows; 1) The relationship between the man group and the woman group was highly correlated as well as between the student group.1 and the student group.2 hense these groups statistically showed no difference in satisfaction ratings. 2) Pedestrian sidewalk width, cleanness, pavement materials and construction condition can be significant variables of satisfaction of urban pedestrian sidewalk. 3) Factors covering the satisfaction of urban pedestrian sidewalk have been found to be Environment of pedestrian sidewalk, Vegetation of pedestrian sidewalk and Form of pedestrian sidewalk. By using the control method for the number of factors, C.P. has been obtained as 62.8%.

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Assessment on Thermal Environment and Human Thermal Comfort in Residential Building Block through Field Measurement (실측을 통한 공동주택 단지 내에서의 온열환경 및 거주자 쾌적감 평가에 관한 연구)

  • Lim, Jong-Yeon;Hwang, Hyo-Keun;Song, Doo-Sam;Kim, Tae-Yeon
    • 한국태양에너지학회:학술대회논문집
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    • 2008.04a
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    • pp.311-317
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    • 2008
  • As outdoor environment become worse due to concentration of population in large cities, the importance of environmental control strategies such as the arrangement of green space or water space and ventilation paths, has been increasingly recognized. However, most of the studies focus on the assessment on outdoor thermal environment, few studies focus on the interrelationship between thermal environment in residential block and human thermal comfort. The aims of this study is to develop the outdoor planning method to reduce the heating/cooling load in an apartment unit or entire block by the sustainable approaches in outdoor environmental design. In this paper, on the basis of the prior studies, the effect of the outdoor thermal environment on human thermal comfort will be analysed.

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