• Structural Engineering and Mechanics
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• 제50권5호
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• pp.589-603
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• 2014

Expressions for determining the value of the impact force as reported in the literature and incorporated into code provisions are essentially quasi-static forces for emulating deflection. Quasi-static forces are not to be confused with contact force which is generated in the vicinity of the point of contact between the impactor and target, and contact force is responsible for damage featuring perforation and denting. The distinction between the two types of forces in the context of impact actions is not widely understood and few guidelines have been developed for their estimation. The value of the contact force can be many times higher than that of the quasi-static force and lasts for a matter of a few milli-seconds whereas the deflection of the target can evolve over a much longer time span. The stiffer the impactor the shorter the period of time to deliver the impulsive action onto the target and consequently the higher the peak value of the contact force. This phenomenon is not taken into account by any contemporary codified method of modelling impact actions which are mostly based on the considerations of momentum and energy principles. Computer software such as LS-DYNA has the capability of predicting contact force but the dynamic stiffness parameters of the impactor material which is required for input into the program has not been documented for debris materials. The alternative, direct, approach for an accurate evaluation of the damage potential of an impact scenario is by physical experimentation. However, it can be difficult to extrapolate observations from laboratory testings to behaviour in real scenarios when the underlying principles have not been established. Contact force is also difficult to measure. Thus, the amount of useful information that can be retrieved from isolated impact experiments to guide design and to quantify risk is very limited. In this paper, practical methods for estimating the amount of contact force that can be generated by the impact of a fallen debris object are introduced along with the governing principles. An experimental-calibration procedure forming part of the assessment procedure has also been verified.

• 경영과정보연구
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• 제36권4호
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• pp.1-19
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• 2017

최근 공유가치창출(CSV: Creating Shared Value)이 초미의 관심을 끌고 있다. 이는 기존의 기업의 사회적 책임(CSR: Corporate Social Responsibility) 성과에 사회적 경제적 가치창출이라는 사회적 문제해결의 대안이 될 수 있다는 시각이 작용하기 때문이다. CSR과 CSV의 성과를 구분하여 확인하기는 어려움이 있다. 따라서 CSV 성과에 대한 실증분석 기법의 개발과 소비자의 CSV에 대한 인식 및 태도가 검증될 수 있는 방법론의 개발이 필요하다. 기업은 가치사슬의 혁신을 통한 사회문제의 해결과 더불어 경쟁우위를 점할 수 있어야 한다. 진일보한 CSV 논의가 필요한 시점으로 파악하는 까닭은 아직 CSV가 초기 연구 단계에 머물러 있는 실정이기 때문이다. 이에 본 연구는 우선적으로 CSV 의의와 필요한 배경, 기업의 사회적 책임(CSR)과 공유가치창출(CSV)의 상호비교 분석을 하였다. 더 나아가 CSV의 기존 연구의 범위가 매우 협소했던 한계점을 넘어 가치사슬에서 CSV의 필요성을 피력하고자 한다. 오늘날 다수의 기업들은 기업의 사회적 책임을 수행하기 위한 노력을 기울여 왔다. 그러나 기업의 지속성장성 측면에서 단순히 CSR의 충족만으로는 수익창출을 위한 비즈니스모델로써는 한계가 있음이 지적되었다. 하나의 대안으로 최근 공유가치창출 도입의 필요성이 제기되고 있는 것이다. 선행연구를 통해 가치사슬관점의 CSV를 경제적 사회적 문화적 가치가 기업이미지 및 기업신뢰도를 매개로 구매의도로 이어지는 인과관계를 실증분석을 통해 밝혀 보았으며 구체적인 연구 결과는 다음과 같다. 첫째, 사회적 가치와 문화적 가치는 기업이미지에 긍정적 영향을 미치는 것으로 나타났다. 이는 CSV 활동을 통하여 소비자들이 해당 기업에 좋은 인상을 가질 수 있도록 하는 단초가 됨을 시사한다. 둘째, 사회적가치는 기업신뢰도에 긍정적 영향을 미치는 것으로 파악되었다. 따라서 CSV가 기업의 비용으로만 인식되는 것이 아닌 미래의 발전과 더불어 상생의 대안이 될 수 있다는 관점으로 접근해 나가야 할 것이다. 셋째, 기업이미지와 기업신뢰도 모두 구매의도에 영향을 미치는 것으로 나타났다. CSV 활동을 통해 기업에 대한 호의적인 평가를 유도할 수 있다는 관점에서 기업의 최종 목표인 지속적 이익창출과 연계된다는 것을 감안하여 중장기적 전략으로 접근할 필요성이 있다고 판단된다.

• 한국생활과학회지
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• 제7권1호
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• pp.39-51
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• 1998

This study was carried out with the purpose of capturing current state of Korean family life culture related to childrearing. The Questionnaire developed for this study in order to delineate the values and perceptions related to general childrearing practices in present Korean families consisted of 73 items concerning prenatal care and child birth, child caring and rearing, and role division and value education. Subjects were mothers of young and primary school children currenly residing in Seoul area and Choongchung province of South Korea. Four hundred and four questionnaires were analyzed, and the summary of results were as follows. First, both the respect for children's individual needs concerning food, clothing, and health-related behaviors and the pursuit of convenience in everyday life on the part of mothers appeared to be important and valued by Korean mothers. Second, the basic values and traditional meanings of family events such as prenatal care, children's birthday, especiall the first one, and family rituals and gatherings still appeared to be exsiting and influential, but there seemed to have been some changes both in their formal aspects and detail contents. Third, meaningful differences in childrearing attitudes were found according to mother's place of growth, educational level, and her employment status. Finally, traditional distinction between sexes and sex-role division in childrearing seemed to have weakened to some extent, which was particularly among mothers with higher educational level or residing in big cities.

• 한국건설관리학회논문집
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• 제13권6호
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• pp.71-83
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• 2012

최근 행정중심복합도시와 혁신도시, 미군기지 이전사업을 중심으로 건설공사에서의 비용절감 및 품질향상, 기술개발 및 가치구현을 목적으로 기술제안입찰방식 적용이 확대되고 있다. 이로 인하여 기술제안입찰에서 중요 평가항목 중의 하나인 '생애주기비용 개선방안'에 대한 관심이 높아지고 있으며, 특히 건축물 생애주기비용에 대한 신뢰성 확보 및 객관적인 평가를 수행할 수 있는 방안을 마련하기 위해 노력하고 있다. 하지만 기술제안입찰에서의 생애주기비용 개선방안에 대한 적용사례의 부족, 원안에 대한 초기공사비의 왜곡, 불변가와 현재가의 혼재, 입찰업체간 산정기준의 모호성, 용어의 불명확성, 작성양식의 미흡 등의 문제점이 지적되고 있는 실정이다. 따라서 본 연구에서는 기술제안입찰에서의 평가항목 중 생애주기비용 개선방안에 대한 참여업체별 변별력을 확보하고 체계적인 생애주기비용 평가를 수행하기 위하여 작성지침 및 분석기준, 작성양식에 대한 개선방안을 제시하였다.

• 한국지역사회생활과학회지
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• 제15권4호
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• pp.127-136
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• 2004

Local fairs are often part of the economic development strategy of rural areas. This study aims to find out marketing strategies for promoting the sales of regional specialty products through local festivals in rural Korea. The data were collected in late 2003 (from a sample of interviews and surveys from 351 visitors. The data were analyzed using the SPSS computer program. The results were as follows; First, the factors that visitors were considered in purchasing were quality (49.5％), commemorative value (36.9％), and reliability (33.0％). And the top reasons cited for not buying were lack of distinction (45.1％) and high prices (26.6％). The discount rates expected in markets was 16.8％. Second, 49.8％ of visitors has spent over 10,000 won and their purchase pattern has been for themselves and their family. Third, the public organizations for certi(ication for visitors were the National Agricultural Cooperative Fedration (37.9％) and the Ministry of Agriculture and Forestry (MAF) (22.5％). In conclusion, it was important for local stakeholders to provide more locally-manufactured, seasonal and traditional food, and to plan more locally characteristic events for their fairs. Further recommendations have included having a guide showing pricing and quality standards for products bought at rural fairs, developing product ideas for inducing impulse purchases, active promotion and marketing at event sites, and setting a standard system of warranties on products under the certification of the local authorities and with the financial support of the MAF Such recommendations were aimed at increasing the sale of traditional and regional specialty products at local festivals.

• Journal of Animal Science and Technology
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• 제47권3호
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• pp.481-490
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• 2005

Nitrate contamination in water system is a critical environmental problem caused by excessive application of chemical fertilizer and concentration of livestock. In order to prevent further contamination, therefore, it is necessary to understand the origin of nitrate in nitrogen loading sources and manage the very source of contamination. The objective of this study was to examine the nitrate contamination sources in different agricultural system by using nitrogen isotope ratios. Groundwater and runoff water samples were collected on a monthly basis from February 2003 to November 2003 and analyzed for nitrogen isotopes. The nitrate concentrations of groundwater in livestock fanning area were higher than those in conventional and organic fanning area and exceeded the national drinking water standard of 10mg N/ l. The ${\delta}^{15}N$ranges of chemical fertilizer and animal manure were - 3.7${\sim}$+2.3$\textperthousand$ and +12.5${\sim}$26.7$\textperthousand$, respectively. The higher ${\delta}^{15}N$ of animal manure than those of chemical fertilizer reflected isotope fractionation and volatilization of '''N. The different agricultural systems and corresponding average nitrate concentrations and ${\delta}^{15}N$ values were: conventional farming, 5.47mg/e, 8.3$\textperthousand$; organic fanning, 5.88mg/e, 10.1$\textperthousand$; crop-livestock farming, 12.5mg/e, 17.7%0. These data indicated that whether conventional or organic agriculture effected groundwater and runoff water quality. In conclusions, relationship between nitrate concentrations and ${\delta}^{15}N$ value could be used to make a distinction between nitrate derived from chemical fertilizer and from animal manure. Additional investigation is required to monitor long-term impact on water quality in accordance with agricultural systems.

• 한국약용작물학회지
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• 제26권1호
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• pp.26-31
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• 2018

Background: Angelica gigas, A. sinensis, and A. acutiloba are commercially important in the herbal medicine market, and among them, A. gigas has the highest economic value and price. However, their similar morphological traits are often used for fraud. Despite their importance in herbal medicine, recognition of the differences between Angelica species is currently inadequate. Methods and Results: A multiplex polymerase chain reaction (PCR) method was developed for direct detection and identification of A. gigas, A. sinensis, and A. acutiloba. The gene for the distinction of species was targeted at ITS in the nucleus and trnC-petN gene in chloroplasts. The optimized multiplex PCR in the present study utilized each Angelica species-specific primer pairs. Each primer pair yielded products of 229 base pairs (bp) for A. gigas, 53 bp for A. sinensis, 170 bp for A. acutiloba. Additionally non-specific PCR products were not detected in similar species by species-specific primers. Conclusions: In the present study, a multiplex-PCR assay, successfully assessed the authenticity of Angelica species (A. gigas, A. sinensis, and A. acutiloba). and whole genome amplification (WGA) was performed after DNA extraction to identify, the species in the product. The detection method of raw materials developed in the present study could be applied to herbal medicine and health functional food management.

• 한국작물학회지
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• 제36권1호
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• pp.22-33
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• 1991

간장이 다른 수도 2품종에 대하여 NaCl, KCl, Mannitol을 처리하고 잎의 신장과 광합성능의 반응을 조사하였다. 그리고 염처리에 의하여 잎의 신장이 일시적으로 정지하고 신장률이 둔화되는 현상 및 높은 농도에서 광합성능이 저하되는 원인에 대하여 고찰하였다.

• 자원환경지질
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• 제13권3호
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• pp.159-166
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• 1980

A model study was conducted for the investigation of apparent resistivity variation along with electric resistivity variation of host rock and dip variation of bed. Experiments were carried out for the cases of horizontal and dipping beds in a water tank by using Wenner and Schlumberger arrays and by changing salinity of water. The ratios of resistivity values of the bed to that of brine were 1 : 10, 1 : 50, 1 : 100 and 1 : 500. Natural coally-shale of $55cm{\times}35cm{\times}3.5cm$ was used as a bed for experimental model, and brine as a host rock. Equi-resistivity curves and characteristic curves were obtained for each case of the experiment. The equi-resistivity curve was drawn both on the cross section parallel to strike of bed and longitudinal section perpendicular to it. The characteristic curve was drawn on the cross section. In the case of dipping bed of different dips, the curves are parallel to the boundary of the bed in the upper part of the bed, and are inclined to the opposite direction with the same angle of the dip of bed in the lower part. We can deduce, from the equi-resistivity curves, the location, shape and dip of the bed. It is shown in the characteristic curves that when the ratio of resistivity value of bed to that of host rock increases, the slope of curves becomes steeper, location of low-resistivity zone lower, and the width of it narrower. The slope of curves also becomes steeper when dip of bed increases. We can deduce, from the characteristic curves, the ratio of resistivity values between adjacent beds. It was found out from the experiments that electric resistivity method could be applicable to prospecting for underground geology with an electric resistivity contrast of 1 : 10. This fact strongly suggests that distinction of coal from coally-shale could be possible in a certain field condition.

• 한국통신학회논문지
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• 제39C권5호
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• pp.447-455
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• 2014

본 논문에서는 무안경식 3차원 영상처리 기법 중 대표적인 집적 영상 기법을 고려하여 전송 에러를 극복하여 영상 품질을 향상시키는 우선순위 전송 기법을 제안한다. 집적 영상의 각 복셀을 구성하고 있는 픽셀들의 유사성에 기반하여 전송 우선순위를 다르게 설정하고 이에 따라 변조 방식을 다르게 적용한다. 즉, 복셀을 구성하는 해당 픽셀들의 분산값이 작은 경우에는 높은 우선순위를 부여하여 에러에 강인한 특성을 갖는 변조 레벨을 사용하여 전송하고, 복셀을 구성하는 해당 픽셀의 분산값이 큰 경우에는 낮은 우선순위를 부여하여 에러율은 높아지지만 빠른 전송률을 제공하는 변조 기법을 사용하여 전송한다. 우선순위의 구분 없이 동일한 변조 레벨을 사용하는 기존 방식 대비, 우선순위가 높은 중요한 영상 데이터 비트열에 에러에 강인한 변조 레벨을 적용한 제안 방식의 경우에 수신 영상의 peak to sidelobe ratio (PSR)이 개선됨을 확인할 수 있다.