• Wind and Structures
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• 제3권3호
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• pp.143-158
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• 2000

This report presents the findings of a one-year monitoring effort to empirically characterize and evaluate the nature of near-ground winds for structural engineering purposes. The current wind engineering practice in the United States does not explicitly consider certain important near-ground wind characteristics in typical rough terrain conditions and the possible effect on efficient design of low-rise structures, such as homes and other light-frame buildings that comprise most of the building population. Therefore, near ground wind data was collected for the purpose of comparing actual near-ground wind characteristics to the current U.S. wind engineering practice. The study provides data depicting variability of wind speeds, wind velocity profiles for a major thunderstorm event and a northeaster, and the influence of thunderstorms on annual extreme wind speeds at various heights above ground in a typical rough environment. Data showing the decrease in the power law exponent with increasing wind speed is also presented. It is demonstrated that near-ground wind speeds (i.e., less than 10 m above ground) are likely to be over-estimated in the current design practice by as much as 20 percent which may result in wind load over-estimate of about 50% for low-rise buildings in typical rough terrain. The importance of thunderstorm wind profiles on determination of design wind speeds and building loads (particularly for buildings substantially taller than 10 m) is also discussed. Recommendations are given for possible improvements to the current design practice in the United States with respect to low-rise buildings in rough terrain and for the need to study the impact of thunderstorm gust profile shapes on extreme value wind speed estimates and building loads.

• Computers and Concrete
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• 제17권1호
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• pp.1-27
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• 2016

Final construction project cost is significantly determined by construction rate. The Industrialized Building System (IBS) was promoted to enhance the importance of prefabrication technology rather than conventional methods in construction. Ensuring the stability of a building constructed by using IBS is a challenging issue. Accordingly, the connections in a prefabricated building have a basic, natural, and essential role in providing the best continuity among the members of the building. Deficiencies of conventional precast connections were observed when precast buildings experience a large induced load, such as earthquakes and other disasters. Thus, researchers aim to determine the behavior of precast concrete structure with a specific type of connection. To clarify this problem, this study investigates the capacity behavior of precast concrete panel connections for industrial buildings with a new type of precast wall-to-wall connection (i.e., U-shaped steel channel connection). This capacity behavior is compared with the capacity behavior of precast concrete panel connections for industrial buildings that used a common approach (i.e., loop connection), which is subjected to monotonic loading as in-plane and out-of-plane loading by developing a finite element model. The principal stress distribution, deformation of concrete panels and welded wire mesh (BRC) reinforcements, plastic strain trend in the concrete panels and connections, and crack propagations are investigated for the aforementioned connection. Pushover analysis revealed that loop connections have significant defects in terms of strength for in-plane and out-of-plane loads at three translational degrees of freedom compared with the U-shaped steel channel connection.

• Tribology and Lubricants
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• 제30권4호
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• pp.205-211
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• 2014

Recent studies emphasize the importance of pivot stiffness in the analysis of tilting pad bearings (TPBs). The present paper develops a finite element model of the pad pivot and compares the predicted pivot stiffness to the results of Hertzian contact model calculations. Specifically, a finite element analysis generates tetrahedral mesh models with ~40,000 nodes for a ball-socket pivot and ~50,000 nodes for a rocker-back pivot. These models assume a frictionless boundary condition in the contact area. Increasing the applied loads on the pad in conjunction with increasing time steps ensures rapid convergence during the nonlinear numerical analysis. Predictions are performed using the developed finite element model for increasing the differential diameters between the pad pivot (or ball) and the bearing housing (or socket). The predictions show that the pivot contact area increases with decreasing differential diameters and increasing applied loads. Further, the maximum deformation occurring at the pivot center increases with increasing differential diameters and increasing applied loads. The pivot stiffness increases nonlinearly with decreasing differential diameters and increasing applied loads. Comparisons of results of the developed finite element model to those of Hertzian contact model calculations assuming a small contact area show that the latter model underestimates the pivot stiffnesses predicted by the finite element models of the ball-socket and rocker-back pivots, particularly for small differential diameters. This result implies the need for cautionduring the design of pivot stiffness by the Hertzian contact model.

• 마케팅과학연구
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• 제17권4호
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• pp.223-245
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• 2007

Purpose: While empirical importance of dimensionality of perceived value is widely accepted, our understanding of experiential value dimensions in other retail channels and other cultures has not been explicitly tested. This study attempted to determine if the dimensions of experiential value scale (EVS) by Mathwick, Malhotra, and Rigdon (2001) identified in US catalog and Internet contexts could be applied in other international markets (South Korea) and in other retail channels (department store versus Internet shopping mall). Methodology/Approach: Two data sets, one from 220 department store shoppers and the other from 359 Internet shopping mall shoppers, were analyzed. Findings: Confirmatory factor analysis confirmed four different EVS dimensions by retail channels. Overall, entertainment and intrinsic enjoyment values were found to be more important in department store while economic and efficiency value dimensions were interpreted critical in Internet shopping mall context. Visual appeal aspect constitutes distinct value dimension in two channels. Practical Implications: One separate dimension of time efficiency in Internet shopping mall suggests that more efficient web design and functions that can save time and promote convenience are needed to better accommodate their customers. Internet has heavily relied on traditional attributes, such as factual information, price comparability, and brand name reliance. However, this study suggests that Internet shopping mall retailer should offer visual diversion and stimulation just as brick and mortar shopping malls do. Originality /Value of Paper: Although the research findings must be viewed as tentative because the results are from one country, they provide a rich basis for further understanding the dimensions of experiential value in other international markets and other retail channels. Category: Research Paper

• 대한가정학회지
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• 제38권6호
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• pp.149-169
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• 2000

The purpose of this study was to examine the environmental characteristics of adolescents in low-income families, identify the high-risk & protective factors among environmental contexts surrounding adolescents, and investigate the relative importance of high-risk & protective factors to adolescents'psychological and behavioral adjustment separately. The present study was the primary research of developing prevention program for adolescents'deviant behaviors in low-income families. Subjects of this study consisted of 176 adolescents drawn from 8 social-welfare institutions in Chungbuk province. The pilot study was done to examine the applicability of survey instrument. Data were analyzed by the frequency, percentage, Pearson correlation, stepwise regression using SPSS/WIN program. The results were as followings: 1. There was statistically correlated with each other in environmental high-risk and protective factors except an housing environment. The results implies that environmental contexts itself surrounding adolescents in low-income families can be either high-risk factors or protective factors. 2. The adolescents in low-income families perceived that stresses from consumer and school environments were high-risk factors among other environmental contexts. 3. The adolescents in low-income families perceived that resources from friend and school were protective factors among other environmental contexts. 4. The stresses from friend and eating behaviors were significant factors predicting adolescents'relative psychological adjustment. However, the behavioral adjustment was not predicted by environmental contexts. 5. The resources from school, consumer, and eating behaviors were significant factors predicting adolescents'relative psychological adjustment. Also, the resources from school, eating behavior, and family were predictors of behavioral adjustment. This research implies that the findings can be based on the development of prevention program for adolescents deviant behaviors in low-income families.

• KIEAE Journal
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• 제16권3호
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• pp.47-55
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• 2016

Purpose: This study was aimed at providing the basic checklist as a means to assess the crime risk in physical environment of the pedestrian passage at residential area. Method: For this purpose, the preliminary checklists were selected according to the review of the precedent studies of checklists in exterior pedestrian passage. The usefulness and the importance of the preliminary checklists were analyzed through the seven expert group meetings, the 87 questionnaires survey of the crime experts & the architectural/urban experts, preliminary assessment and field survey. Results: The assessment categories of checklists were sorted into six types, i.e. spatial structure & function, lighting, landscaping, security facilities, other facilities and cleaning & maintenance. The 49 checklists were proposed according to the assessment categories. The final checklists were divided key checklists and general checklists based on the results of experts' weighting of each list item. There were significant differences between crime experts' weighting and architectural/urban experts' weighting in several checklists, i.e. dividing between pavements and streets, the brightness of light, white light.

• International Journal of Human Ecology
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• 제14권2호
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• pp.53-68
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• 2013

The purpose of this study was to highlight the importance of 'marital preparation skill' by focusing on more substantial and tangible skills in marriage life, and to conduct an exploratory research to examine the current conditions and gender differences in marital preparation skills of college students. Data were gathered through a self-administered questionnaire in four universities located in Seoul and Gyeong-gi areas in the spring of 2013, and a total of 332 senior students chosen were used for data analysis. Based on the instrument used in Olson & Olson's(2000) PREPARE/ENRICH Program, the present study sought to suggest a measurement tool with the moniker of 'marital preparation skill' that included seven domains: conflict resolution skill, sexual relationship skill, household labor skill, financial management skill, leisure management skill, parenting preparation skill, and parental role skill. Each domain consisted of four items and thus, a total of 28 items were utilized for this study. Descriptive statistics were analyzed in order to examine the degree of marital preparation skills, and t-tests were conducted in order to assess the gender differences in marital preparation skills. The main results of this study are as follows: First, overall the degree of marital preparation skills of male students was higher than that of female students. Particularly, female students were lower than male students in the skills of financial management and conflict resolution. Second, regarding the basic household labor skill related to clothing and housing life, male students showed higher than female students, implying the impact of military life. Third, even though the degree of consciousness about appropriate preparation of parenthood and parental role seemed to be heightened, the actual degree of readiness of college students revealed to be insufficient. Male students had a much higher degree of confidence and sacrifice acceptance about parenthood, and understanding about their parents' child-rearing style than female students, while the mindset of child-rearing participation of male students was lower than that of female students. Findings of this study can be used as basic data for developing more effective and differentiated educational programs of marital preparation skills for men and women.

• 한국건설관리학회:학술대회논문집
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• 한국건설관리학회 2006년도 정기학술발표대회 논문집
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• pp.692-697
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• 2006

건축물의 유지관리에 대한 중요성이 부각되고 건축물의 수명연장에 대해 많은 관심이 집중되고 있다. 최근 수도권을 중심으로 도심지 등의 주택용지가 부족함에 따라 해결책으로 주상복합건물의 건설이 빠른 속도로 증가하고 있다. 주상복합건물은 부지 내에서 토지이용의 극대화를 가져왔지만, 유지관리단계에서는 관리비용 분담과 관리범위 한계 등으로 인해 상가시설과 주거시설 이해당사자간에 갈등이 발생하는 등 많은 문제점을 내포하고 있다. 본 논문의 목적은 건축물의 초기성능을 유지하고 개선할 수 있도록 설계단계에서 유지관리성능 향상을 위한 체크리스를 제시하는 것이다. 이를 위해 문헌조사 및 설문조사를 실시하여 유지관리의 문제점을 도출하고 설계단계에서의 검토항목을 작성하여 건축계획분야를 중심으로 건축물의 유지관리성능 향상을 위한 가이드라인을 제시하였다. 본 연구결과는 건축물의 생애기간동안 사회적, 물리적, 기능적 변화 요구에 대응하여 유지관리 성능향상에 도움을 줄 것으로 기대된다.

• 자원ㆍ환경경제연구
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• 제29권2호
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• pp.171-194
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• 2020

본 연구는 유가충격이 거시경제에 미치는 영향을 재고찰하고 이 영향이 경기변동에 따라 어떻게 달라지는지 분석했다. 우선 로지스틱 확률분포를 통해 1980년 이후 한국의 경기침체 확률을 추정하고 이를 통계청에서 발표한 경기순환주기와 일치하도록 교정하였다. 본 연구에서는 유가충격에 대한 거시경제변수의 반응을 경기확장국면과 경기침체국면에 따라 분석하기 위해 비교적 최근 논의되고 있는 평활국면전환 백터자기회귀(STVAR)모형을 설정하였다. 분석 결과, 불황기의 유가상승 충격은 국내총생산에 중장기적으로 음의 영향을 미치나, 호황기의 국내 총생산은 유가상승 충격에 통계적으로 유의미한 반응을 하지 않는 것으로 나타났다. 이러한 결과는 호황기에 나타난 견고한 소비수요 증진과 경상수지 증가의 복합적인 요인 때문인 것으로 추측된다. 또한 유가충격이 물가에 미치는 영향은 물가상승의 지속성 측면에서 경기침체국면과 경기확장국면에 매우 상이하게 관찰되었다. 이러한 연구결과는 최근 에너지경제학에서 다양하게 활용되고 있는 국면전환모형(regime switching model)이 갖는 중요성을 보여준다.

• 한국농촌건축학회논문집
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• 제19권4호
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• pp.1-8
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• 2017

The purpose of this study is to deduce dwelling selection criterion and to consider change of values and consciousness of dwelling on people who return to farming & going to village. For that, questionnaire of evaluation of housing choice is conducted by people who return to farming & going to village in Jellanam-do by the AHP. The results are as follows. First, four factors as the primary hierarchy structure and 12 factors as the secondary hierarchy structure of dwelling selection criterion are deduced. The primary hierarchy are "education environment", "economic & Convenience in life", "residence safety and image", and "economic value". Second, weight value deduced from the primary hierarchy structure is showed that "economic & convenience in life(0.345)" is the highest and next is "education environment(0.262)". "Residence safety and image(0.237)", and e "economic value(0.157)" is relatively low(C.I. 0.213). Third, for the secondary hierarchy structure, the case of life convenience is showed that economic condition(0.403) is the highest, the case of educational condition is showed that education facilities(0.479), the case of residence safety and image is showed that residence area(0.490) is the highest, and the case of economic importance is showed that financial technology(0.470) is the highest.