• 한국지반공학회논문집
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• 제20권7호
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• pp.99-105
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• 2004

포화점토가 보오링공에서 불교란시료로써 채취되면, 부의 간극수압이 체적팽창을 억제한다. 이 점토시료에는 지반중에서 작용한 평균주응력이 등방적으로 작용하며, 이 평균주응력은 수직응력보다 작고, 수평응력보다 크다. 그러므로 시료는 비배수조건하에서 수직으로 늘어나고, 수평으로 수축하게 된다. 통상적인 압밀시험은 이와 같이 변형된 시료를 그대로 사용하여 압밀링 크기와 똑같이 성형한 후 수행한다. 따라서 지반중의 유효상재압이 재하되면, 이 압력이 수평응력보다 크기 때문에 압밀량이 늘어나게 된다. 즉 압밀시험공시체는 현장의 압밀거동을 정확하게 나타내지 못하고 항상 아래에 위치하게 된다. 이 논문에서는 상기와 같은 시료변형의 영향을 고려하여, 압밀시험 공시체에 유효상재압이 재하되었을때 수평방향으로 비배수 변형하여 압밀링 내경에 밀착해도록 하였다. 그리고 제안하는 시험법의 적용성과 결과를 통상적인 압밀시험결과와 검토하였다.

• 전기학회논문지
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• 제58권3호
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• pp.467-477
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• 2009

Renewable Portfolio Standard (RPS) is a regulatory policy that requires the generation companies to increase the proportion of renewable energy sources such as wind, solar, LFG, fuel cell, and small hydro. Recently, Korean government decided to increase the portion of renewable energy to 3% to total electricity generation by 2012 from the current level of 0.13%. To achieve this goal, an innovative plan for market competitiveness would be required in addition to the present Feed-In-Tariff (FIT). That is Korean government has taken it into consideration to introduce a Renewable Portfolio Standard (RPS) as an alternative to FIT. This paper reviews the impact of RPS on the long-term fuel mix in 2020. The studies have been carried out with the GATE-PRO (Generation And Transmission Expansion PROgram) program, a mixed-integer non-linear program developed by Hongik university and Korea Energy Economics Institute. Detailed studies on long-term fuel mix in Korea have been carried out with four RPS scenarios of 3%, 5%, 10% and 20%. The important findings and comments on the results are given to provide an insight on future regulatory policies.

• Environmental Engineering Research
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• 제20권4호
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• pp.342-346
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• 2015

Haloacetonitriles (HANs) are nitrogenous disinfection by-products (DBPs) that have been reported to have a higher toxicity than the other groups of DBPs. The adsorption process is mostly used to remove HANs in aqueous solutions. Functionalized composite materials tend to be effective adsorbents due to their hydrophobicity and specific adsorptive mechanism. In this study, the removal of dichloroacetonitrile (DCAN) from tap water by adsorption on thiol-functionalized mesoporous composites made from natural rubber (NR) and hexagonal mesoporous silica (HMS-SH) was investigated. Fourier-transform infrared spectroscopy (FTIR) results revealed that the thiol group of NR/HMS was covered with NR molecules. X-ray diffraction (XRD) analysis indicated an expansion of the hexagonal unit cell. Adsorption kinetic and isotherm models were used to determine the adsorption mechanisms and the experiments revealed that NR/HMS-SH had a higher DCAN adsorption capacity than powered activated carbon (PAC). NR/HMS-SH adsorption reached equilibrium after 12 hours and its adsorption kinetics fit well with a pseudo-second-order model. A linear model was found to fit well with the DCAN adsorption isotherm at a low concentration level.

• International Journal of CAD/CAM
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• 제3권1_2호
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• pp.19-29
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• 2003

Disassembly is a fundamental process needed for component reuse and material recycling in all assembled products. Integral attachments, also known as 'snap' fits, are favored fastening means in design for assembly (DFA) methodologies, but not necessarily a favored choice for design for disassembly. In this paper, design methods of a new class of integral attachments are proposed, where the snapped joints can be disengaged by the application of localized heat sources. The design problem of reversible integral attachments is posed as the design of compliant mechanisms actuated with localized thermal expansion of materials. Topology optimization technique is utilized to obtain conceptual layout of snap-fit mechanisms that realizes a desired deformation of snapped features for joint release. Two design approaches are attempted and design results of each approach are presented, where the geometrical configuration extracted from optimal topologies are simplified to enhance the manufacturability for the conventional injection molding technologies. To maximize the magnitude of deformation, a design scheme has been proposed to include boundary conditions as design variables. Final designs are verified using commercial software for finite element analysis.

• 한국조리학회지
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• 제14권2호
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• pp.170-180
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• 2008

The purpose of this study was to measure the causal relationships between past consumption, health belief, subjective, attitude, intention and purchase of organic foods. Total 326 copies of questionnaire were completed. The structural equation model was used to measure the causal effect among constructs. The results demonstrated that the confirmatory factor analysis model provided a good model fit. The proposed model yielded a significantly better fit to the data than the baseline model and the extended model. The effects of past consumption, health belief and subjective norm on attitude and intention were statistically significant. The effects of attitude on intention and behavior to purchase organic food were statistically significant. As expected, health belief and subjective had significant effects on behavior to purchase organic foods. Moreover, past consumption, health belief and subjective norm had indirect influences on intention through mediated variables. Based on the empirical results and findings, some suggestions are provided to the institutions concerned so as to facilitate this organic sector's on-going expansion in the food industry.

• 대한가정학회지
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• 제18권4호
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• pp.31-39
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• 1980

The basic pattern of skirt should be functional in addition to be fit the body. The author paid special attention to the expansion and contraction of the shell which were made the lower trunk and thigh caused by sitting motions. The replicas of the shell were taken by using a gypsum method on 1 female under 4 standardized motions; standing motion, (basic motion), sitting on the chair with flextion 90' at the hip and the knee joints sitting with dropping knees, and sitting with benting legs side wards. Those replicas obtained were developed to the patterns and changes in shape and area of those were measured. Typical displacement and transformation of the shell surface patterns were showed geographycally fig 5-1 to 5-4. mean values of expansion and constriction were obtained by measuring the shell surface on 60 female under the 4 motions. the mean values of it were showed numerically in Table 1-1 to 1-3. The following results were obtained; 1. Vertical constriction of front of the shell were observed near sulcus in guinalis, and vertical extension were near the knees. Horizontal extension were observed near the thighs and the knees. 2. Vertical constrictions of the back of the shell were observed near the knees. It seemed to be influnced the flexion angles of knee points. vertical extension were near gluteus and thighs. Horizontal constriction were small, and horizonlal extension were near gluteus. 3. The high rates of constriction and extension were found near sulcus in guinalis, glutes, and knees. 4. The rates of constriction and extension on the waist line were very low. 5. The highest values of constriction and extension were found in hip and knees.

• 유통과학연구
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• 제10권11호
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• pp.21-30
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• 2012

Purpose - This study aimed to analyze the strategy of late domestic entrants into the Chinese retail market, focusing on the case of Lotte-Mart, given that there are few studies on market entry strategies of domestic retail companies in China. Research Design, data, methodology - The methodology of this paper is a case study approach, focusing on literature reviews and a few interviews. We conducted a survey by disseminating questionnaires and conducting interviews focusing on the Chinese retail market, and analyzed Lotte-Mart's market entry strategy in China. Results - Lotte-Mart chose M&A as the mode of entry, pursuing quick market entry and rapid expansion. It chose small to medium size cities with relatively less competition. Subsequently, Lotte-Mart devoted significant effort towards localization, attempting to organize stores and assorting products to fit the Chinese consumers' preferences. It operated CSR programs to increase its brand awareness and to create a favorable brand image. Conclusions - Lotte-Mart now needs to devise alternative corporate strategies for business expansion and growth. An understanding of the Chinese retail market and the case study analysis of Lotte-Mart's market entry strategy offers significant insights for domestic retail companies looking to expand into China.

• 천문학회보
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• 제45권1호
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• pp.50.4-51
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• 2020

We report our discovery of Raman-scattered He II λ6545 feature in young planetary nebulae NGC 6886 and NGC 6881 which indicates the existence of atomic hydrogen components. Considering sharply increasing cross-section of hydrogen atom near the resonance, Raman-scattered He II features are a useful diagnostic tool to investigate the distribution and kinematics of H I region in planetary nebulae. The high-resolution spectroscopic observation was carried out using BOES installed on the 1.8 m telescope of BOAO. We estimate the column density of H I region and its expansion velocity using our grid-based Monte-Carlo radiative transfer code. We assume that the H I region is uniformly distributed in spherical shell geometry with an opening angle and expands with constant speed. Our best-fit model is shown with the column density NHI = 3 × 1020 cm-2 and expansion speed vexp = 25 km s-1 with the opening angle ~ 25° for NGC 6886, and NHI = 4 × 1020 cm-2 and vexp = 30 km s-1 with the opening angle ~ 35° for NGC 6881. We present brief discussions on the late-stage of evolution of stars with mass > 3 M⊙.

• 한국항해항만학회:학술대회논문집
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• 한국항해항만학회 2019년도 춘계학술대회
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• pp.125-126
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• 2019

컨테이너 부산김해공항은 부산 경남 지역의 중요 항공 거점이며, 세계 5대 항만인 부산항과 근접해 있으면서도 그 규모나 역할에 맞지 않게 약소한 실정이다. 현재, 김해공항의 지속적인 취항 노선의 증가 및 이용 항공사가 증가하고 있지만, 포화 상태인 시설 및 군사공항을 겸하고 있어 높은 한계성에 직면하고 있다. 본 연구에서는 부산김해공항의 현 시점 및 개발 계획을 기초로 선용품물류를 중심으로 하여 부산국제공항의 발전을 예상하여, 국제공항의 시설 확충에 따른 물류비용 및 시간의 저감을 고려한다. 또한, 선용품물류를 기준으로 주요 항공노선의 우선순위를 검토하여 부산의 항만물류산업에 기여를 검토하고자 한다.

• 보건의료산업학회지
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• 제11권2호
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• pp.129-142
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• 2017

Objectives : The purpose of this study was to identify the main variables of difference in high school students' oral health promotion behaviors among adolescents and to improve their academic and oral health promotion behaviors. Methods : The research subjects consisted of 311 high school students in Jeonju. Results : The adequacy of the hypothetical model accounted for 46.9 % of the oral health promotion behavior. The Redundancy of all variables showed the value of the positive values, indicating that the Goodness of fit was greater than the optimum value of the model, and the model of the PLS was a desirable model. The effects of perceived benefits, self efficacy, and social support on oral health promotion behaviors were found to be higher in oral health promotion behaviors. Conclusions : This study is expected to have a significant impact on the perception of the oral health promotion for adolescents in the future and will contribute to the expansion and generalization of Pender's oral health promotion model.