• Title/Summary/Keyword: Settlement period

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Influence of Rheological Properties of Lightweight Foamed Concrete on Preventing Foam Collapse (경량 기포 콘크리트의 레올로지 특성이 소포억제에 미치는 영향)

  • Lee, Hyang-Sun;Jeon, Jong-Woon;Jo, Mujin;Kee, Seong-Hoon;Han, Dongyeop
    • Journal of the Korean Recycled Construction Resources Institute
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    • v.6 no.4
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    • pp.304-310
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    • 2018
  • The aim of the research is to provide possibility of quality controlling by rheological properties for lightweight foamed concrete. The lightweight foamed concrete achieves its low density by containing air bubbles (foam) produced during the mixing process. Therefore, containing foamed volume during setting period is critical for the securing the performance as an insulating material. In this research, regarding foam collapse during the setting period, rheolgocial properties of fresh state lightweight foamed concrete were assessed to get its relationship with volume stability, or foam stability. For the experiment regarding foaming factors including mixing time, mix design of contents for materials, rheological properties of fresh state lightweight foamed concrete were tested with its density and settling depth. Based on the settling depth with various factors, relationship with rheological properties was analyzed, and especially, close relationship of plastic viscosity and settling depth was found. Therefore, from the results of this research, it is considered to contribute on suggesting a new approach of quality controlling for lightweight foamed concrete using rheological test method.

Longitudinal Trajectories of Mental Health Among North Korean Defectors: A Four-Year Follow-Up Study of Loneliness, Depression, and Life Satisfaction (북한이탈주민 정신건강의 종단적 추세: 외로움, 우울, 삶의 만족도에 대한 4년 추적 연구)

  • Park, So Hee;Hong, Jin Pyo;An, Ji Hyun;Lee, Hye Rin;Kim, Myung Hyun;Chang, Hyein
    • Anxiety and mood
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    • v.17 no.2
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    • pp.49-58
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    • 2021
  • Objective : The purpose of this study was to investigate the longitudinal trajectories of life satisfaction, loneliness, and depression and to identify the factors that influence these trajectories in North Korean Defectors (NKD). Methods : NKD (n=300) who registered in the multi-regional adaptation center (Hana Center), within three years of settling in South Korea, were recruited into this study. Life satisfaction, loneliness, and depression were assessed with self-report questionnaires over a period of 4 years (7 waves of data). Latent growth modeling was conducted to assess the changes in life satisfaction, loneliness, and depression. Results : Findings from both unconditional and conditional models (with gender, South Korea settlement age, household income, marital status, and PTSD at wave 1) indicated a linear increase in loneliness and depression, and a linear decrease in life satisfaction over the 4-year period. In the conditional model, gender predicted the intercept of life satisfaction and depression. In addition, PTSD predicted the intercept of life satisfaction, loneliness, and depression and slope of depression. Conclusion : Our finding suggests that the mental health of NKD tends to deteriorate over time after settling in South Korea. Therefore, continuous support is necessary for their successful adaptation to the South Korean Society.

Analgesis of Clearly Reinforced Soil Wall Behavior by Model Test (모형시험에 의한 점성토 보강토벽의 거동분석)

  • 이용안;이재열;김유성
    • Proceedings of the Korean Geotechical Society Conference
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    • 1999.11c
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    • pp.85-94
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    • 1999
  • Reinforced Soil Wall has several merits comparing with conventional retaining wall. The conventional method has the limit of wall height, ununiform settlement of the foundation ground, quality assurance of the embankment body, shortening of construction period, economical construction and so on. Basis of previous mentioned things reinforced soil wall is the substitutional method of conventional retaining wall and its necessity is continuously increasing. The embanking material used in reinforced soil wall is generally limited such as a good quality sandy soil, and in many case constructors have to transfer such a good embanking material from far away to construction site. As a result, they would pressed by time and economy. If poor soils could be used embanking material, for example, clayey soil produced in-situ by cutting and excavation, the economical merit of reinforced soil wall would be increased more and more. Likewise, a lot of study about laboratory experimental behavior of reinforced soil wall using a good quality soil is being performed, but is rare study about clayey soil containing much volume of fine particle relatively in korea. In this study, the authors investigated behavior of the geosynthetic reinforced and unreinforced soil walls using clayey soil as embanking material in view of horizontal movement of walls, bearing capacity and reinforcement stress.

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Nature and Issues of Hospital Management (병원관리학의 본질과 과제)

  • 황인경
    • Health Policy and Management
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    • v.1 no.1
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    • pp.153-160
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    • 1991
  • Hospital Management, as a branch of science, is now in a formative period in Korea. Proper understanding on the scienctific nature and issues of the subject, therefore, is important for both its developement and education of the students. As an academic subject, Hospital Management can be pointed out to have three characteristics, Firstly, when looking it in teleological viewpoint, it is a branch of health science. Ultimate goal of the hospital lies in promoting and keeping health of the people residing in the catchment area in which it places, Secondly, in terms of its contents, Hospital Management can be divided into tow subsubjects ; hospital administrative management and hospital business management. The former stands at the point of looking the hospital as the object of goverment administration, while the latter as the subject of organizational operation. Flanlly, Hospital Management, in its academic appoach, is a science that adopts management theories, what is called, traditional and/or modern. For the settlement and development of the Hospital Management, four major issues were suggested for discussion now and in the future. They include ; (1) boundary between Hospital Management and its related academic fields (2) subdivision of the subject and its contents, (3) activation of study, theortical and empirical, and (4) distinction of the level of lecture among lecfnical, four-year and gradudate courses.

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The Effects of individual Characteristics and Health Beliefs on North Korean Refugees' Health Behavior (하나원 입소 북한 이탈주민의 개인적 특성과 건강 신념이 건강 행위에 미치는 영향)

  • Jeon, Jeung-Hee;Park, Young-Suk
    • Research in Community and Public Health Nursing
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    • v.23 no.1
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    • pp.82-90
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    • 2012
  • Purpose: The purpose of this study is to provide base data for preparing plans that North Korean (NK) Refugees can adjust themselves to our society with a healthy mind after they get over their health problems using the Health Belief Model, knowing the relationship between individual characteristics and health beliefs, and health behavior. Methods: The subjects were 304 NK adult refugees in Hanawon. Data were collected by demographic questionnaire, health behavior scale, self-efficacy scale, perceived benefit scale, perceived barrier scale, perceived seriousness, perceived sensibility, and individual characteristics. Results: The factors influencing the health behavior of NK refugees were perceived benefits, self-efficacy, the period in the third country and experience in being expelled to NK, and these variables were describing 31.4% of the health behaviors of refugees. Conclusion: The perceived benefits and self-efficacy of health belief and specific experiences related to refugee affected NK refugees' health behavior.

Evaluation of Applicability of HMS-25 as the Railroad Roadbed Material (철도 노반재로서의 수경성 입도 조정 고로슬래그(HMS-25)의 적용성 평가)

  • 황선근;이성혁;이시한;최찬용
    • Journal of the Korean Geotechnical Society
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    • v.16 no.1
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    • pp.157-165
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    • 2000
  • The applicability and performance of HMS-25 as the railroad roadbed materials were evaluated through the model and laboratory tests. The uniaxial compression test of HMS-25, model soil box test, and combined resonant column and torsional shear test were performed for static and dynamic analysis of railroad roadbed. The uniaxial compression test result of HMS-25 shows steady increase in strength due to hardening chemical reaction between HMS-25 and water. The result of model soil box test reveals that railroad roadbed of HMS-25 is better than that of soil in several aspects such as bearing capacity and settlement. The combined resonant column and torsional that shear test result indicates that shear modulus of HMS-25 increases with the power of 0.5 to the confining pressure and that shear modulus increases with the increase of curing period.

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Artificial Habitat Creation of Luciola lateralis (Coleoptera: Lamphyridae) and Research of Breeding Technique for Festival at Hwadamsup, Korea

  • Kang, Seung-Ho;Jeon, Mi-Kyung;Kwon, Soon-Jik;Na, Seok-Jong;Kim, Kyung-Ho;Jeong, Jong-Chul
    • Journal of Forest and Environmental Science
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    • v.34 no.4
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    • pp.275-283
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    • 2018
  • This study created the running water (Bandibooliwon) and lentic water (Sooryunwon) artificial habitats of Luciola lateralis in Hwadamsup, Gwangju-si, Gyunggi-do from April 2014 to February 2016. Through various habitat types, metapopulation was formed, and more sound population was induced to be maintained via interactions between habitats. We investigated coenosite at the habitat creation-target site, and 20 species in the lentic water site and 38 species in running water site were found. After releasing L. lateralis, we checked the status of settlement of L. lateralis larvae through traps and macroscopy, controlled the flow velocity of the habitats in line with the life cycle of L. lateralis (hatching, larva period, landing, pupation, copulation, and oviposition), and shaped gentle slope at water side, and planted moss. We artificially supplied melanian snails (Semisulcospira sp.), the food source, in the running water site and induced stable feeding. Also, We created artificial insectary, bred larvae stably in winter, and secured firefly population for a festival. Through night time observation, the time most suitable for a festival was confirmed to be from 20:30 to 22:00.

A Study on the Vernacular Houses of Ulleung-Island (울릉도 민가에 관한 연구)

  • Kim Chan-Yeong
    • Journal of the Korean housing association
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    • v.15 no.5
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    • pp.107-118
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    • 2004
  • The purpose of this study is to analyze the unique characteristics of the vernacular house of Ulleung-Do(island), which shows a different residential culture from the main land. For this purpose, this study examined the characteristics of the location, spatial arrangement, and floor-plan of the house and also tried to understand how these basic elements were changed and why these changes were occurred. The result of this study is as follows: First, the house was located on the mountain area and was oriented toward the various bearings. Second, the house usually did not have annexes and most residential space was installed on a main building. Third, the floor-plan of the house was developed from a basic two-Kan (with single row) house type in a early settlement period to three-Kan, four-Kan, and five-Kan house types in later periods. While the development of house type proceeded. the main building was functioned as a complex space for both residential and storage purposes. Some houses were gradually developed into a middle and upper-class house shape by installing annexes. The change of the floor-plan and the house size was the result of self-sustained living culture influenced by the natural environment of the island and of changes of residential conditions as well.

Interaction assessment and optimal design of composite action of plastered typha strawbale

  • Olatokunbo, Ofuyatan;Adeola, Adedeji;Maxwell, Omeje;Simon, Olawale
    • Advances in materials Research
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    • v.6 no.2
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    • pp.221-231
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    • 2017
  • The concept design of the typha strawbale masonry came up as a result of the urgent demand for a means of constructing sustainable buildings, both in rural and urban settlement, not only suitable for dwellers but for keeping farm products by structures that will respond to the environmental eco-system, coupled with the fact that such structures are also affordable, durable and easy to maintain during their service period. The effects of contact between plaster and the stacked strawbale of a masonry needs to be established and design optimization for durability and stability of the masonry be obtained. The assessment will involve the application of plaster materials (cement and natural earth) to the wall specimen panels. Past works have shown that plastered strawbale walls have adequate resistance against the appropriate vertical loads, and further showed that the earth plaster can bear higher stress than the cement plastered straw bale. There is the implication that the collapse or response of the earth-strawbale wall is significantly higher compared to that of cement-strawbale from other straw-based masonries. Therefore the allowable stresses of plastered typha strawbale shall be predicted for their optimum values using SAP2000. The stress stability of each masonry is obtained by analytical model using the best fit variables for the wall height and thickness.

A Study on the Analysis of Landscape Preference in the Rural Settlement by Land Use Transition (토지이용변화를 이용한 농촌경관 선호성 분석에 관한 연구)

  • 서주환;최현상
    • Journal of the Korean Institute of Landscape Architecture
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    • v.27 no.2
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    • pp.69-79
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    • 1999
  • This study identifies the features of landscape elements on the fifteen districts with the idea of land use area and visual quantity of pictures by analyzing the air photo. Therefore, the sensibility of observer is comprehended through simulating the landscape evaluation and the landscape preference with using slide film. The study is divided into three periods to understand the transition of rural landscape as the social and cultural environments have been changed. The first period is the New Community Movement which affected the rapid change of social and cultural environments. The second and third periods are the prior and post time at the rearrangement of administration district in the Tae-Jeon Broad City. The result of this study is explained below part; 1. The transition of rural landscape has been occurred as the land use pattern has been altered. The change of pattern has affected an increase of the natural space and the structure change of agricultural productive space. 2. In the regression analysis, the regression model of landscape preference and land use ratio show; Landscape preference = 3.632 - 11.618 (Residential Area) - 4.227 (Equipped Farm). The explanation variables defined as Residential Area and Equipped Farm, and the relationship of those factors shows negative. Therefore, the increase of other building will make the rural landscape lower and worse.

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