• 한국물환경학회지
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• 제26권5호
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• pp.841-849
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• 2010

Soil erosion is an natural phenomenon. However accelerated soil erosion has caused many environmental problems. To reduce soil loss from a watershed, many management practices have been proposed worldwide. To develop proper and efficient soil erosion best management practices, soil erosion rates should be estimated spatially and temporarily. The Universal Soil Loss Equation (USLE) and USLE-based soil erosion and sediment modelling systems have been developed and tested in many countries. The Sediment Assessment Tool for Effective Erosion Control (SATEEC) system has been developed and enhanced to provide ease-of-use interface to the USLE users. However many researchers and decision makers have requested to enhance the SATEEC system for simulation of soil erosion and sediment reflecting effects of single storm event. Thus, the SATEEC R factors were estimated based on 5 day antecedent rainfall data. The SATEEC 2.1 daily R factor was applied to the study watershed and it was found that the R2 and EI values (0.776 and 0.776 for calibration and 0.927 and 0.911 for validation) with the daily R were greater than those (0.721 and 0.720 for calibration and 0.906 and 0.881 for validation) with monthly R, which was available in the SATEEC 2.0 system. As shown in this study, the SATEEC with daily R can be used to estimate soil erosion and sediment yield at a watershed scale with higher accuracy. Thus the SATEEC with daily R can be efficiently used to develop site-specific soil erosion best management practices based on spatial and temporal analysis of soil erosion and sediment yield at a daily-time step, which was not possible with USLE-based soil erosion modeling system.

• 한국지구과학회지
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• 제39권3호
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• pp.275-290
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• 2018

본 연구는 과학공학 융합 수업을 통해 학생들의 공학과 공학자에 대한 인식이 어떻게 변화되었는지 알아보기 위한 연구이다. 본 연구에서 사용한 과학공학 융합 수업은 제한된 예산과 시간동안 공학적 문제를 해결하는 24차시 수업으로 설계되었으며 20명의 초등 과학 영재 학생들에게 적용하였다. 본 연구의 주요데이터는 공학자 그림 그리기와 설명문항, 그리고 이에 대한 개별 인터뷰와 초점 집단 면접을 통해 수집되었으며, 공학자 그리기에 대한 설명과 인터뷰는 전사내용을 토대로 양적(빈도분석과 대응표본 t-검증), 질적 분석 방법을 모두 사용하여 분석하였다. 과학공학 융합 수업은 과학 영재 학생들의 공학 설계에 대한 이해에 긍정적인 영향을 미치는 것으로 나타났다. 또한 공학과 공학자, 그리고 공학과 사회의 관계에 대한 인식도 바람직한 방향으로 변화하였다. 공학은 여러 명이 협력하는 사회적인 활동이라는 인식, 그리고 공학자의 윤리의식, 공학의 사회적 가치 등 공학과 사회의 관계에 대한 인식도 바람직하게 변화하였다.

• 한국항해항만학회지
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• 제40권6호
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• pp.413-420
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• 2016

우리나라에서 항만은 국가전체 교역 물동량의 90% 이상을 처리하고 있어 경제적 중요성이 높으며, 항만건설에 대한 막대한 투자와 국가경쟁력에 미치는 영향을 고려한다면 항만의 지속가능한 운영은 중요한 이슈이다. 하지만 항만의 경쟁력과 지속가능성을 다룬 기존의 연구들은 항만의 시설규모, 항만효율성 등의 항만 내 물류활동을 중심으로 연구가 이루어져 외부환경변화에 대처하고 중장기적인 지속가능한 경쟁력을 확보하기 위해서는 항만이용자들의 기대와 요구뿐만 아니라 지역사회 및 환경적 요인 등의 외부적인 환경변화를 고려한 항만경쟁력 확보 방안에 관한 연구가 필요한 시점이다. 이에 본 연구에서는 주변지역과 경제적, 사회적, 환경적 연결성을 가지고 있는 항만의 지속가능한 경쟁력 확보를 위한 유럽연합(EU)의 SuPorts와 PPRISM 사례를 분석하여 외부환경변화, 공급사슬 내 성과를 고려한 중장기적인 관점에서의 성과측정지표 개발의 필요성과 항만별 특성에 맞는 평가기준의 필요성, 국내실정에 맞는 항만의 지속가능한 성과측정 방안에 대한 시사점을 도출하였다.

• 한국토양비료학회지
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• 제43권1호
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• pp.105-112
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• 2010

벼 유기농업은 한국에서 빠르게 확산되고 있다. 유기재배에서 벼 생육은 토양 물리적 특성과 토양 미생물의 기능에 크게 의존한다. 본 연구는 무경운 답에서 유기농업을 위하여 토양 물리성과 미생물 생체량에 미치는 녹비작물의 효과를 검토하였다. 시험구는 무경운, 무경운+볏짚, 무경운+호밀, 무경운+자운영 그리고 경운구를 3반복으로 죽곡통에서 2005년 5월에서 2006년 10월까지 수행하였다. 경운구는 2005년과 2006년 모두 토양 가밀도가 가장 높은 반면 공극률은 가장 낮았다. 무경운+호밀 처리구는 공극률이 가장 높았으며 무경운 처리구의 표토 관입저항은 경운구 보다 낮았다. 담수 전 2005년과 2006년 토양 미생물 생체량 탄소 함량은 무경운+자운영 처리구가 477 mg $kg^{-1}$ 및485 mg $kg^{-1}$으로 가장 높았고 무경운+호밀 처리구는 413 mg $kg^{-1}$ 및 484 mg $kg^{-1}$였으며 경운 처리구는 363 mg $kg^{-1}$ 및 445 mg $kg^{-1}$을 나타냈다. 시기적으로 토양 미생물 생체량 탄소 함량은 유수형성기에 낮아지는 경향이었다. 연구결과 녹비작물을 시용한 무경운 재배기술은 경운에 비해 토양 공극률과 토양 미생물 생체량 탄소 함량을 크게 개선하였다.

• Journal of Nutrition and Health
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• 제31권1호
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• pp.96-101
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• 1998

The prevalence of iron deficiency in later infancy and the toddler years(25% to 40% at 1 year of age) has not decreased remarkably , except in Western countries. The purpose of this study was to 1) determine the relationship between current feeding practices and iron status, and 2) assess compliance to infant feeding instructions. Two groupsof infants were examined. The first group of 302 infants aged 6 to 24months was seen at a well baby clinic while the second group of 135 infants of the same age group was assessed by venipuncture. Cutoff values for laboratory tests were as follows ; hemoglobin<11g/dL, mean corpuscular volume (MCV) <72fl ; red cell distribution width(RDW)>15% ; serum ferritin level<10ng/ml ; and transferrin saturation (serum iron(TIBC)<10%. The diagnosis of iron deficiency anemia (IDA) was made when a low hemoglobin level was associated with either low ferritin orlow transferrin saturation . Of the 302 children brought to the well baby clinic , 12.3%(n=37) were found to have anemia (hemoglobin<11.0/dL). In terms of children grouped according to feeding practices, it was found that children with anemial comprised 32.0% (24/75) of the prolonged breast-fed group (Group A), significantly more than the 4.0%(7/176) of the artificial milk feeding group(Group B). and 3.9%(2/51) of the switched from breast milk to iron -fortified weaning foods group(Group C).Among the 107 children with IDA , iron deficiency in 105 children(98.1%) was suggested by their dietary histories ; exclusive or prolonged breast-feeding for more than 6 months without iron fortification in 98 infants ; cow's milk consumption> 500ml/day without iron fortification during infancy(n=12), or >800ml without iron-fortified foods after infancy(n=15) ; and the use of unfortified forumula or unbalanced diets, mainly limited to rice gruel. Despite the relatively high (79.6%) motivation on the part of the infants mothers and supervison by professional personnel, the poor results in the infants receiving iron fortified foods were due to poor compliance(85.75). Among the mothers of 98 IDA patients who were contacted by telephone , it was revealed that 29% did not give the oral iron preparation for more than 2 months. Furthermore, negligence or disregard by the parents occurred in 14% of the case , discontinuance of the oral iron preparation by the parents due to side effects occurred in 6%, and the children's refusal or poor oral intake and no further trial occurred in 6%. The dietary history of a large group of infants was highly predictive of their risk for anemia . Continued consumption of breast milk until the age of 1 year is not warranted unless iron-fortified foods are given concomitantly. Because there is a problem with compliance, more successful and safe strategies for preventing iron deficiency woold included dual coverage in the from of therapeutic iron supplementation as well use of iron-fortified foods for teddlers who are at risk of iron deficiency.

• 한국정밀공학회지
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• 제17권10호
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• pp.192-199
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• 2000

The design of multi-stage gear drives is a time-consuming process because it includes more complicated problems, which are not considered in the design of single-stage gear drives. The designer has no determine the number of reduction stages and the gear ratios of each reduction stage. In addition, the design problems include not only dimensional design but also configuration design of gear drive elements. There is no definite rule or principle for these types of design problems. Thus the design practices largely depend on the sense and the experiences of the designer, and consequently result in undesirable design solution. A new and generalized design algorithm has been proposed to support the designer at the preliminary phase of the design of multi-stage gear drives. The proposed design algorithm automates the design process by integrating the dimensional design and the configuration design process. The algorithm consists of four steps. In the first step, the user determines the number of reduction stages. In the second step, gear ratios of every stage are chosen using the random search method. The values of the basic design parameters of a gear are chose in the third step by using the generate and test method. Then the values of the dimensions, such as pitch diameter, outer diameter and face width, are calculated for the configuration design in the next step. The strength and durability of each gear is guaranteed by the bending strength and the pitting resistance rating practices by using AGMA rating formulas. In the final step, the configuration design is carried out using simulated annealing algorithm. The positions of gears and shafts are determined to minimize the geometrical volume (size) of a gearbox while avoiding interferences between them. These steps are carried out iteratively until a desirable solution is acquired. The proposed design algorithm is applied to the preliminary design of four-stage gear drives in order to validate the availability. The design solution has considerably good results in both aspects of the dimensional and the configuration design.

• 한국습지학회지
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• 제17권3호
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• pp.245-250
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• 2015

지방자치단체 수준에서의 습지 보전 현황을 파악하기 위해 경상남도를 대상으로 실행계획과 과제현황을 분석하였다. 습지보전실천계획은 기반체계(습지조사, 습지보호지역 람사르습지 관리, 습지관리전략 수립), 습지보전 및 현명한 이용(습지복원, 생물관리, 이용시설조성), 교육 및 인식증진, 협력체계구축(국내외 습지보전기관과의 협력)으로 구분하였다. 2010년부터 2013년 까지 총 42개 과제(145건)가 수행되었고 총 88,899백만원이 경상남도의 14개 기관에서 수행된 것으로 분석되었다. 과제의 규모와 예산은 점차 감소하는 추세에 있지만 지속적으로 추진되는 과제가 많으며, 수행 주체는 일부 지방자치단체에 집중되어 있는 양상을 보였다. 각 과제가 얼마나 많은 성과를 만들었는가를 판단하기에 앞서, 전통적인 습지관리방법이나 행정적 법적 지원이 충분하지 않은 상황에서 여러 가지 시도를 통해 지방정부 차원에서 습지를 관리하고 이를 조례로 입법화한 것은 지방자치단체 수준의 습지보전에 높은 의미를 가지는 것으로 평가할 수 있었다. 단일 지방자치단체의 역량만으로 국가 네트워크를 통한 자료 공유 또는 법적 제제는 무리가 따르므로 이를 위한 중앙정부차원의 법적 근거 마련과 타 지방자치단체와의 협력체계 구축이 시급한 것으로 판단된다.

• Journal of Nutrition and Health
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• 제42권2호
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• pp.183-188
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• 2009

There has been a need to update the current Codex nutrient reference values (NRVs) which had been established following the Helsinki Consultation in 1988. The main purposes of NRVs are to help consumers compare the nutrient content of different food products and estimate the usefulness of a food product in terms of its percentage contribution to the overall healthful diets. The establishment of Codex NRVs for labelling purposes is intended to facilitate the goals of protecting consumers' health and ensuring fair practices in food trade. When revising the Codex NRVs several issues are needed to discussed, which are: 1) Consideration of population groups whether to have one set of NRVs for general population or to have several sets of NRVs for each population groups, 2) Determination of scope of nutrients such as what nutrients to include and what reference values to choose and 3) Development of principles for establishing NRVs such as the selection of suitable reference values among many including recommended intake/recommended dietary allowances, estimated average requirement and upper levels to extract NRVs. This paper will discuss the above issues and the inputs and efforts that the Korean Nutrition Society had put into to carry out the project, "International Collaboration on the Revision and Addition of the Codex Nutrient Reference Values for Food Labelling Purposes," and to ascertain relevant scientific principles and evidences that are utilized for establishment and revision of the Codex NRVs.

• 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.

• 한국생활과학회지
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• 제21권3호
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• pp.505-526
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• 2012

The purpose of this research is to investigate changes in ethical consumption practices after taking an undergraduate course 'Consumption and Ethics'. Through Qualitative & Quantitative research methods, students' pre-course and post-course attitudes were compared to understand changes in behavior. Before taking the course 'Consumption and Ethics', undergraduate participants displayed little regard for ethical consumption, instead displaying primary sensitivity to price and values based on self-centered and conspicuous consumption. After taking the course 'Consumption and Ethics', participants displayed a more altruistic awareness of consumption on society and the environment. In addition, participants displayed a stronger sense of pride as ethical consumer. These emerging values were contrasted with conflicting feelings resulting from the higher prices often associated with ethical products, feelings of regret resulting from ethically-based impulse purchases, and an inability to categorically evaluate the reliability of available information on the ethical products. However, participants demonstrated a willingness to practice ethical consumption and recommend ethical consumption to their friends and neighbors. Overall, participants in the study demonstrated a strong shift to be an ethical consumer as a result of taking the course 'Consumption and Ethics'.