• Title/Summary/Keyword: Bedding Factor

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A Study on the Thermo-mechanical Behavior of Underground Openings in lsotropic and Structurally Snisotropic Rock Masses (등방 및 이방성 암반내 공동의 열역학적 거동에 관한 전산모델연구)

  • 문현구;주광수
    • Tunnel and Underground Space
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    • v.1 no.2
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    • pp.181-203
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    • 1991
  • The effects of geologic structures such as rock joins and bedding planes on the thermal conductivity of a discontinuous rock mass are studied. The expressions for the equivalent thermal conductivities of jointed rock masses are derived and found to be anisotropic. The degree of anisotropy depends primarily on the thermal properties contrast between the joint phase and surrounding intact rock, the joint density expressed as volume fraction and the inclination angle of the joint. Within the context of 2-dimensional finite element heat transfer scheme, the isotherms around a circular hole are analyzed for both the isotropic and anisotropic rock masses in 3 different thermal boundary conditions. i.e. temperature, heat flux and convection boundary conditions. The temperature in the stratified anisotripic rock mass is greatly influenced by the thermal properties of the rock formation in contact with the heat source. Using the excavation-temperature coupled elastic plastic finite element method, analyzed is the thermo-mechanical stability of a circular opening subjected to 10$0^{\circ}C$ at a depth of 527m. It is found that the thermal stress concentration was enough to deteriorate the stability and form a plastic yield zone around the opening, in contrast to the safety factor greater than 2 resulted form the excavation-only analysis.

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House Dust Mites and Associated Environmental Factors in Homes of Atopic Children: a Case-Control Study (아토피 아동 가정내 집먼지 진드기 농도와 환경요인: 환자 대조군 연구)

  • Kim, Sung-Ho;Park, Dong-Jin;Byun, Hyae-Jeong;Lee, Hyun-Soo;Oh, In-Bo;Sim, Chang-Sun;Kim, Yang-Ho;Yoon, Chung-Sik
    • Journal of Environmental Health Sciences
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    • v.38 no.3
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    • pp.204-212
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    • 2012
  • Objectives: The purpose of this study was to determine house dust mite concentrations in living rooms and bedding materials in atopic case-control groups. Methods: Fifty four homes with children suffering atopic diseases as cases and fifty one homes without atopic diseases as controls were selected after diagnosis at three elementary schools in Ulsan City. Dust samples were collected from the living rooms and bedding materials in each home during summer and winter with a vacuum cleaner and analyzed for house dust mites using enzyme-linked immunosorbent assay (ELISA). Environmental factors and family history were surveyed during sampling. Results: Both species of house dust mite Dermatophagoides farina (Der f 1) and Dermatophagoides pteronyssinus (Der p 1) were found in all homes. Derf1 concentrations were much higher than Der P1 concentrations, both in atopic homes (1518.9 vs. 27.0 ng/g. dust, respectively) and non-atopic homes (810.8 vs. 44.3 ng/g. dust, respectively). Der f 1 concentrations were significantly higher in the atopic group than in the non-atopic group (atopic: 1518.9 ng/g.dust, non-atopic: 810.8 ng/g.dust, p = 0.035). However, total house dust mite Der p 1 concentrations were significantly higher in the non-atopic group than in the atopic group (atopic: 27.0 ng/g.dust, non-atopic: 44.3 ng/g.dust, p = 0.035). Multiple regression implied that mothers with family history of atopic diseases (OR = 4.79, 95% CI = 1.81-12.69), Der f 1 concentrations (OR = 1.74, 95% CI = 1.07-2.81), and air freshener use (OR = 4.60, 95% CI = 1.72-12.34) had significant associations with atopic children. Conclusion: House dust mite Der f 1 concentrations were associated with atopic children. This study suggests that parents should reduce house dust mite Der f 1 concentrations through environmental controls.

A Study on the Technique for Evaluating Geological Suitability about the Route of a Linear Civil Engineering Structure (선형토목구조물에 대한 지질학적 측면 노선의 적정성 평가기술)

  • Hwang, Hak-Soo;Moon, Sang-Ho;Kim, Yong-Il;An, Dong-Kwang;Ha, Sung-Ho;Song, Moo-Young
    • The Journal of Engineering Geology
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    • v.18 no.4
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    • pp.501-509
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    • 2008
  • It is very important in designing civil engineering structures that the quantification of geological informations must be carried out in terms of importance. In this study, the geological informations are quantified and evaluated using analytic hierarchy process (AHP). A professional group was organized with 30 people in the field of civil engineering, transport, and geology. On the assumption that the civil engineering structure is linear such as highway or railroad, a survey of the group in terms of geological and hydro-geological elements has found that the hierarchy structure is composed of four levels. And fault structure is a primary factor which causes the stability of a linear civil engineering structure. The importance of geological items are arranged with fault (0.456), foliation/bedding plane(0.l65), lineation(0.144), ground water(0.124), and rock type(0.111).

Tafoni Geomorphic Development in the Western Coast of Dongdo of Dokdo, Korea (독도 동도 서쪽 해안의 타포니 지형 발달)

  • Hwang, Sang-Ill;Park, Kyung-Geun
    • Journal of the Korean association of regional geographers
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    • v.13 no.4
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    • pp.422-437
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    • 2007
  • Dokdo has historical and political meaning in relation to the territorial problems with Japan. The area can be the main factor to explain the formation and development process of East-Sea as exposure volcanic island at East-Sea with Ulreong-island. Accordingly, it also has an important meaning of physical geography aspects In this research, it is perceived the geomorphological development process of slope due to the salt weathering which is considered as the most important factor to understand whole geomorphology of Dokdo. And researched how a geomorphology of this sort affects to animal and plants. The peculiar geomorphology is tafoni which is a weathering geomorphology and one of the remarkable geomorphology in preservation of Dokdo. Tafoni at west part of Dongdo is distributed intensively near shoreline which is composed tuff. The shape of tafoni is mainly massive, circle and oval in Massive tuff breccia layer also is formed toward horizontality bedding direction in Bedded lapilli tuff. Tafoni in Dokdo is constituted after middle of Holocene. This fact can be proved by ranging at surface of sea-cliff which is formed wave erosion after middle of Holocene sea-level reaching to present level. Tafoni is also the most contribute factor of geomorphology dissection of Dokdo as it is eroded the bed rock with salt weathering. In bottom part of tafoni it has an important function for habitat of birds. Herbaceous plants are on it. To procrastinate of bed rock dissection by growth of Tafoni, conservation of vegetation and soil are most important factor.

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A Study on the Original Form and Architectural Elements in the Palace of Yu, Jin gyeong's Hanok (유진경 가옥(현 북촌문화센터)의 원형과 궁궐요소 차용)

  • Park, Sang-Wook
    • Journal of architectural history
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    • v.23 no.5
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    • pp.7-22
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    • 2014
  • It is identified that an initial person who built of 'Seoul Gyedong Modernized Hanok(former Min Hyeong-gi house)' used as 'Bukchon Culture Center' in present, was not Min Hyeong-gi, but his wife, Yu Jin-gyeong, and she built it when 8 years went on after his death(1879~1973), and the construction year was at the gate of Chuseok in 1921. Yu Jin-gyeong was Head Family's Eldest Daughter-in-law in family of Yeo Heung-min who was an influential person at the late Joseon Dynasty and was widow who had only son for 3 generations. And she built this house and moved to gain daughter and live futher grandchilds together in law in new nest. It is arranged that an annex surrounds with main building as the central figure. And this house emulates Yeonkeong-dang in backyard of the Changdeok Palace for 'preservation of main building' and Chim-bang-ga-toe applied on a bedroom in a palace is applied around nobleman family's the main room. It is rare case and expresses that a palace factor is borrowed. Yu Jin-gyeong's house is that a tradition Hanok is adjusted closely in city and central and basing mode as 'protective bedding' and building concept as 'a noble and protective architecture' is realized. So it has a character that development of Hangrang architecture is appeared and Head Family's Eldest Daughter-in-law widow of modern upper class had a special benefit. As well as, a meaning that it is experimental house based on tradition and is build of Hanok with housekeeping as the central figure for appear a form which has minimal Hangrang for housekeeping in yangban family of modern city, can be found.

A Study on the Stability and Mechanism of Three-Hinge Failure (Three-Hinge 파괴의 메커니즘 및 안정성에 관한 분석)

  • Moon, Joon-Shik;Park, Woo-Jeong
    • Journal of the Korean Geotechnical Society
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    • v.33 no.4
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    • pp.5-15
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    • 2017
  • Three-hinge failure occurs in a jointed rock slope with a joint set parallel with slope and a conjugate joint set. Limit Equilibrium Method (LEM) and Finite Element Method (FEM) which are commonly used for slope design, are not suitable for evaluating stability against three-hinge failure, and this study performed parametric study to analyze the failure mechanism and to find influence factors causing three-hinge failure using UDEC which is a commercial two-dimensional DEM based numerical program. Numerical analyses were performed for various joint structural conditions and joint properties as well as ground water conditions. It was found that pore water pressure is the main factor triggering the three-hinge failure and the mode of failure depends on friction angle of basal joint and bedding joint set. The results obtained from this study can be used for adequate and economic footwall slope reinforcement design and construction.

A Case Study on Living Lifestyle Shop Brands focusing on Store Experiential Factors and an Empirical Study on Store Usage Behavior, Product Purchase Motives, Store Attitudes of Living Lifestyle Shop Consumers (리빙 라이프 스타일 숍 브랜드의 매장 체험요소 사례분석과 소비자들의 매장이용행태, 제품구매동기, 매장태도에 대한 실증적 연구)

  • Seo, Gowoomi;Oh, Kyung Wha
    • Fashion & Textile Research Journal
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    • v.19 no.4
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    • pp.448-467
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    • 2017
  • Attention to living lifestyle shops covering with the wide product range including household items, interior decoration, and bedding have recently increased since consumers have been improving their standard of living and income levels and they are getting more interested in up-to-date trends of global living lifestyles. The purpose of this study is first, to analyze the market situation of living lifestyle shops using the case study method and second, to investigate consumer's store usage behavior, product purchase motives, and attitudes to the living lifestyle shops using the empirical study method. For an empirical study, the survey was conducted with 20s to 50s female respondents who have visited living lifestyle shops and a total of 227 responses were analyzed using SPSS 18.0. The results of this study were as follows. The most frequently visit store was MUJI and most of respondents tended to visit the store once a month and their interest and purchase items were household items. Only impulsive purchase motives among other motives of living lifestyle shops, such as others-oriented, situational, and reasonable motives, significantly had a positive effect on store attitudes toward living lifestyle shops. There were differences in purchasing items at living lifestyle shops depending on marriage status and occupation. Purchase motives of living lifestyle products were statistically influenced by demographic factors such as age, marriage status and income level, however store attitudes were not. The managerial implications for living lifestyle shops are discussed limitations and areas for future research as well.

A study on the P.O.P response for the buying trends of General Supermarket (종합슈퍼마켓의 소비자들의 구매경향별 POP광고반응에 관한 연구)

  • Kim, Tae-Sung;Kim, Pan-Jin
    • Journal of Distribution Science
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    • v.8 no.1
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    • pp.35-42
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    • 2010
  • This study is for finding out the relationship between reactions on POP per consumer purchase trends and major factor for making final purchasing decisions after being exposed to POP from large supermarkets. The following results were obtained after the research. First, consumers displayed higher reaction scores on End-Cap in general among POP advertisements. The factors for making final purchase decision are in the order of function > price > brand for household electrical goods, price > design > function for sundry goods and design > price > function for clothing (including bedding). Second, the results of analyzing the differences based on age on impulsive purchase showed that the lower the age the higher the tendency. Unplanned purchase trend also showed higher when younger. The results of this study showed that there are discrepancies in the theory related with existing POP advertisements, that is, the theory that impulsive purchasers have higher POP responses.

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Assessment of Evaporation Rates from Litter of Duck House (오리사 바닥재의 수분 증발량 평가)

  • Lee, Sang-Yeon;Lee, In-Bok;Kim, Rack-Woo;Yeo, Uk-Hyeon;Decano, Cristina;Kim, Jun-gyu;Choi, Young-Bae;Park, You-Me;Jeong, Hyo-Hyeog
    • Journal of The Korean Society of Agricultural Engineers
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    • v.61 no.5
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    • pp.101-108
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    • 2019
  • The domestic duck industry is the sixth-largest among the livestock industries. However, 34.3% of duck houses were the duck houses arbitrarily converted from plastic greenhouses. This type of duck house was difficult to properly manage internal air temperature and humidity environment. Humidity environment inside duck houses is an important factor that directly affects the productivity and disease occurrence of the duck. Although the humidity environments of litters (bedding materials) affect directly the inside environment of duck houses, there are only few studies related to humidity environment of litters. In this study, evaporation rates from litters were evaluated according to air temperature, relative humidity, water contents of litters, and wind speed. The experimental chamber was made to measure evaporation rates from litters. Temperature and humidity controlled chamber was utilized during the conduct of the laboratory experiments. Using the measured data, a multi linear regression analysis was carried out to derive the calculation formula of evaporation rates from litters. In order to improve the accuracy of the multi linear regression model, the partial vapor pressure directly related to evaporation was also considered. Variance inflation factors of air temperature, relative humidity, partial vapor pressure, water contents of litters, and wind speed were calculated to identify multicollinearity problem. The Multiple $R^2$ and adjusted-$R^2$ of regression model were calculated at 0.76 and 0.71, respectively. Therefore, the regression models were developed in this study can be used to estimate evaporation rates from the litter of duck houses.

Stability Analysis of Open Pit Slopes in the Pasir Coal Field, Indonesia (인도네시아 Pasir 탄전에서의 노천채탄장 사면의 안전성해석)

  • 정소걸;선우춘;한공창;신희순;박연준
    • Proceedings of the Korean Society for Rock Mechanics Conference
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    • 2000.09a
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    • pp.183-193
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    • 2000
  • A series of studies such as geological logging data analysis, detailed geological survey, rock mass evaluation, in-situ and laboratory tests, rock strength and mechanical properties of the rock were concerned. The stability of the slope were carried out inorder to design the pit slope and individual benches using the stereographic projection analysis and numerical methods in Roto Pit of Pasir coal fetid. The bedding plane was one of the major discontinuities in the Roto Pit and the dip of which is about $60^{\circ}$in the northern part and $83^{\circ}$in the southern part. The dip of bedding becomes steeper from north to south. The plane and toppling failures are presented in many slopes. In laboratory test the average uniaxial compressive strength of mudstone was 9 MPa and that of weak sandstone was 10 MPa. In-situ test showed that the rocks of Roto north mining area are mostly weak enough to be classified in grade from R2(weak) to R3(medium strong weak) and the coal is classified in grades from R1(Very weak) to R2(Weak). The detailed stability analysis were carried out on 4 areas of Roto north(east, west, south and north), and 2 areas of Roto south(east and west). In this paper, the minimum factor of safety was set to 1.2 which is a general criterion for open pit mines. Using the stereographic projection analysis and the limit equilibrium method, slope angles were calculated as 30~$36^{\circ}$for a factor of safety greater than 1.2. Then these results were re-evaluated by numerical analysis using FLAC. The final slope angles were determined by rational described abode. A final slope of 34 degrees can guarantee the stability for the eastern part of the Roto north area, 33 degrees for the western part, 35 degrees for the northern part and 35 degrees for the southern part. For the Roto south area, 36 degrees was suggested for both sides of the pit. Once the pit slope is designed based on the stability analysis and the safety measures. the stability of 니ope should be checked periodically during the mining operations. Because the slope face will be exposed long time to the rain fall, a study such aspreventive measures against weathering and erosion is highly recommended to be implemented.

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