• 콘크리트학회논문집
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• 제14권6호
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• pp.813-822
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• 2002

본 연구에서 초기재령 콘크리트의 단면 내 수화도와 온도 및 습도분포를 구하는 3차원 유한요소 해석 프로그램을 개발하기 위한 수화도에 따른 재료 모델을 제시하고, 수치해석 절차에 관하여 정립하였다. 재료물성이 급격히 변화하는 초기재령 콘크리트의 거동을 모사하는 과정에서 온도 및 습도에 관련된 재료 물성이 수화도에 따라 결정하였다. 또한 수분거동 연구는 경화한(mature) 콘크리트에 대해서는 여러 연구자에 의해 수행되었지만, 초기재령 콘크리트의 전달계수, 수분용량에 관한 연구는 제대로 정립되지 않은 실정이다. 또한 일반적으로 보통콘크리트에서 무시되는 수분감소항은 고강도 및 고성능 콘크리트의 자기건조(self-desiccation)와 관련된 자기수축(autogenous shrinkage)을 유발하고, 이는 구조물의 장기 내구성 및 사용성 측면에서 중요한 관심사이다. 따라서 본 연구는 초기재령 콘크리트의 온도 및 수축에 의한 응력을 평가하기 위하여, 고강도 및 고성능 콘크리트를 포함한 초기재령 콘크리트의 온도 및 수분거동을 적절히 표현하는 수학적 재료 모델을 제시하고, 콘크리트의 단면 내 수화도와 온도 및 습도분포를 결정하는 3차원 유한요소 해석 프로그램을 개발하였다. 개발된 해석프로그램을 이용한 수치해석 결과는 실험결과와의 비교를 통하여 그 타당성을 검증하였다.

• 한국작물학회:학술대회논문집
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• 한국작물학회 2017년도 9th Asian Crop Science Association conference
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• pp.186-186
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• 2017

Relay intercropping system of direct seeded rice and winter cereal is labor saving cultivation and has high land use efficiency in Japan. In this system, rice seeds are direct seeded into inter-row space of winter cereals (wheat or barley) in March or April. If the direct seeding of rice is conducted before stem elongation phase or using suitable seeder, these are little effect to yield of winter cereals. Though the seeds are generally thiuram treated, it's a matter that seedling establishment rate (SER) of direct seeded rice is low and unstable. The cause of low SER has not been revealed. In present study, with the aim to reveal causes of low SER, we conducted experiments and investigated the SER, and analyzed some factors that might affect SER. Experiment1: In 2015, 2016, we buried rice seeds underground, and investigated the transition of the seed survival rates (SSR). Seeds were thiuram-treated or non-treated. In 2 periods, SSR of thiuram-treated seeds were significantly higher than non-treated seeds. In 2016, thiuram-treated seeds were high in SSR (almost 75%) at April 30th, but low SER (10~27%) after harvest of winter cereals. Therefore, almost all of seed death might have been happen after germination. Analysis 1: We investigated the SER and cultivation conditions in Ibaraki pref. for several years. Meteorological factors were referred from the nearest point of AMeDAS. From mean temperature (MT) among 5days after and before the day, we divided the period of seeding ~June 20 to phase1~4. We defined each phase as below; Phase1: $MT{\leq}10^{\circ}C$, Phase2: $10^{\circ}C<MT{\leq}15^{\circ}C$, Phase3:$15^{\circ}C<MT{\leq}20^{\circ}C$, Phase4: $MT>20^{\circ}C$. We analyzed the correlation of SER and meteorological factors by each phase. Total number of days in phase 1~4 was significantly negative correlated with SER. In phase1, total rain fall and number of soil wetting days were significantly negative correlated with SER. In phase2~4, only MT was significantly positive correlated with SER. This result suggested that rainfalls in phase1 declined seed vigor to emergence from soil surface, by repeated water absorption and re-dry. From these present studies, it was suggested that one of factors of low SER of direct seeded rice in relay intercropping system is changing of water condition by rainfalls in phase1 ($MT{\leq}10^{\circ}C$). To improve SER, it's necessary to consider something seed treatments such as prevent water absorption during phase1. However, 58~60% of seeds seemed to die during May. It's suggested that, if seeds are thiuram treated, almost all of seeds can germinate underground, but the seed vigor to emergence from soil surface are insufficient. Further studies are needed to reveal the rest causes that is happening during emergence from soil surface.

• 한국해안해양공학회지
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• 제18권4호
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• pp.372-382
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• 2006

기존 방파제의 대부분은 항내외 흐름을 차단시키는 불투과성 방파제로서 항내의 수질오염을 심화시키고 있다. 이러한 문제점을 해결하기 위해 최근에 여러 형식의 해수교환방파제가 제안되고 있다. 해수 교환 방파제의 형식에는 흐름을 이용한 조류제, 파랑을 이용한 월류제 등이 있다. 이 중에서 파랑에너지에 의한 해수교환 형식은 항내로 월파되는 월파량의 계산시 적절한 유량계수의 산정을 필요로 한다. 본 연구는 적절한 유량계수의 도입을 통해서 정량적인 월파량을 계산하고, 월류식 해수교환방파제의 해수교환 효과를 검토한 것이다. 파량의 계산은 정상상태의 하천에서 월류제를 넘어가는 월류량을 산정하는데 사용되고 있는 Forchheimer의 식을 시간의존 완경사방정식에 적용하여 가능하도록 하였다. 이 때 가장 중요한 매개변수인 유량계수는 수리모형실험으로 추정하였다. 이와 같은 방법을 제주외항 서방파제의 해수교환 구간에 적용하고 해수교환 성능을 검토해 보았다. 평상 파랑 조건이 파고 3.7 m, 주기 8.5 s, NNW방향일 때, 항내로 공급되는 월파량은 $27.5m^3/s$로 산정 되었다.

• 한국수자원학회논문집
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• 제39권2호
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• pp.99-108
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• 2006

부유사의 거동을 나타내는 데는 이송-확산 방정식이나 이 방정식을 간략화한 식들이 이용된다 이 방정식은 여러 가지 가정하에서 유도되었으나, 이러한 가정에 대해서는 심도있는 검토가 되지 못한 상태에 있다 그 이유는 난류의 측정 자체가 매우 힘들며, 유사가 혼합된 흐름의 경우 물과 유사의 속도를 구별해서 측정하기 매우 힘들기 때문이다. 본 연구는 입자 영상 유속계(PIV, Particle Image Velocimeoy)의 일종인 입자 추적 유속계(PTV, Particle Tracking Velocimetry)를 이용하여 개수로 난류에서 물과 유사의 속도를 측정하는 실험적 연구이다. 측정 결과, 하상에서 어느 정도 떨어진 영역에서는 유사의 속도가 물보다 느린 경향을 보였다. 이 속도 지체의 양은 본 연구의 경우 평균 유속 의 약 $5\%$ 정도였으며, 속도 지체가 최대에 이르는 지점은 $g/h\approx0.05\;(g^{+}=30\~50)$정도인 것으로 나타났다. 유사 입자가 물보다 느리게 이동하는 것은 전적으로 유사의 비중이 물보다 크기 때문으로 보인다. 반면, 하상에 근접한 점성 저층에서는 오히려 유사 입자의 속도가 물보다 빠르게 나타났으며, 이것은 물은 고체 경계면에서 점착 조건에 종속되는 데 반하여, 유사 입자는 점성의 영향을 받지 않기 때문으로 보인다.

• 간호행정학회지
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• 제3권1호
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• pp.119-133
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• 1997

Continuing shift service of clinical nurses can be not only the cause of occupational dissatisfaction by being connected with the change of circadian rhythm and the burden of duties to be applicable to such changes. But also of inviting the lowering of nursing quality by being affected to the resignation of the nurses as the threat to the health of the nurses. This study has selected 500 nurses at random under non-probability sampling who have been serving by shift in 7 general hospitals which have over 400 sickbeds for the purpose of cross-sectional survey design from Sep. 7 through 20, 1996. Standardized modification of the CMI has been used which was designed for Koreans with Cornell Medical Index developed by Broadman and his fellow workers as the study device. The structure of the device was composed of 35 questions on physical appeal(Chronbach's ${\alpha}=8507$) and 22 questions of mental appeal(Cronbach's ${\alpha}=.8166$ totalling 57 questions. The collected data has been computerrized by using SPSS. General character, present symptom, perceived symptom and others are sought by practical number and percentage, and the health condition comparison followed by general characters was conducted by t-test and ANOVA. The post test was by Duncan's test by the level of p<.05. 1) The items of the answer that they have the physical symptom presently by 50% or over of the nurses were as "Do you often have spells of severe dizziness", "Are your eyes often red or inflamed", "Does press or pain in the head often make like miserable", "Are your ankles often badly swollen", "Do pains in the back make it hard for you to keep up with your work". 2) The items of the answer by over 50% of the nurses as the mental symptom at present were "do you fell bad when criticized?", "Do you get angry when everything is against your will?", "do you get angry when ordered to do this and that?", "do you feel uneasy by such a trifle thing?", "do you tremble or are you freightened by sudden sound?". The mental and physical symptoms which have appeared presently in connection with the shift service have been agreed with each other. But the physical condition has been worse than the mental one. 3) In the physical health conditions followed by demosociological character, there were the significant differences by sex, religion and place of residence(p<.05), and in the mental health conditions, there were the significant differences by age, marital status, residence place and the required time for attending hospital(p<.05). 4) There was significant difference by the degree of satisfaction about the duty in both the physical and mental health conditions. In short, the higher the degree of duty satisfaction, the better the health conditions. 5) There were the significant difference according to the times of night duty and whether they take the drug or not or the kinds of the drugs in the physical health conditions related with the characters of night shift. Mental health conditions in the night shift case showed significant differences according to their taking drug or not or the kinds of the drugs(p<.05). I can confirm that the nurses have been affected continuously by the shift service mentally and physically. The maintenance of the physical and mental health of the nurses and its promotion are very important problem to guarantee the quality nursing in the performance of the nursing service continuously and effectively, so the hospital should make every effort to improve the duty conditions by finding out the causes affecting to their health. In the nursing management viewpoint, I think that elevating the satisfaction degree about the duty would be a great help to the promotion of physical and mental health conditions. But what is most important is that the nurses themselves should take care of themselves in maintaining the good conditions in their service in the hospital.

• 한국농촌건축학회논문집
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• 제13권2호
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• pp.1-8
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• 2011

Due to rapid decrease in population of farming and fishing villages and drain of young rural manpower to the cities, aging is being intensified, and the conditions of housing and welfare of elderly households are inadequate. Currently, group home is being discussed as part of specialized housing and welfare support policy for the people in the vulnerable class with poor self-supporting abilities such as the aged living alone in farming and fishing villages, and aged farming and fishing households. So the purpose of this research is to present the basic data for proposing the policy of supplying group home through examining the realities of housing and welfare of the people in the vulnerable class in farming and fishing villages. Survey was conducted on the 4 regions -Cheonan-si, Gongju-si, Yesan-gun, and Seosan-si - whose apartments were all occupied by the residents among the group homes for the elderly living alone in Chungcheongnam-do and the following results were derived from the analysis on the data collected from the survey. First, great effects can be attained at small costs by reorganizing and utilizing the public facilities that are unused or little used and the existing houses that are exposed to risks due to improper maintenance. Second, it can be pointed out that the residential environment of the vulnerable members of society was improved without impairing the existing village landscape. Third, housing welfare was enhanced without investing a large sum of money and the system to promptly cope with negligent accidents and emergency can be built and operated. Fourth, the cases promoted to solve the problems of the poor, unhygienic, and unsafe housing of the elderly and the vulnerable members of society were very positive and well worthy of being presented as planning direction of future group homes in farming and fishing villages. Finally, if they are operated entirely for free, it will cause the lack of the sense of ownership and the problems in securing the budget, so the ways of paying minimum individual housing expenses should be examined. The alternatives of housing welfare for the vulnerable members of farming and fishing villages are needed and the ways of constructive planning and researches should be continuously made. Also, the government's support policy should be actively promoted.

• 한국조경학회지
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• 제18권3호통권39호
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• pp.171-190
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• 1990

It is the purpose of this study to address how to manage the urban vegitation using the concept of Urban Forestry which is relatively new to Korea. When we consider the Urban Forestry as a science, We should understand it interdisciplinary subject which includes Forestry, Horticulture, Urban Planning, Landscape Design, Landuse Planning, Business and Humanities. It may say that people and tree are the fundermental components of Urban Forestry. So there are two ways of Urban Forestry Applications-How people care for trees and How trees care for People-. For the application, this study places the focus on the monetary valuation, tree inventory system and traditional forestry application to urban forest management. Pubic Relation, Communication, Ordinances and Budget are also mentioned as a part of Urban Forestry Policy. Monetary valuation of trees and forests is very important for the proper cognition of their real value. So that, they may be equated and weighed against conflicting uses which would cause to be removed or severely mutilated. A tree inventory system which is the essential part of urban tree management can provide the pertinent information about the present condition of urban tree resource. It may aid in reducing the subjectivity of tree management decisions and stimulate them to be made rapidly and can help reduce potential municipal liability by identifying serious problems in time for corrective maintenance practices to be applied for the maximize community benefits and minimimize public nuisances or hazards. Managers can derive the information from the inventory and use it for the various management plan. When we see the structure of tree inventory system as one of the data base management system, Computer is the best equipment for the efficient management plan. Public relation and communication is also important factors to care the people for urban vegetation management. Volunteer management system is a good example for the public relation and communication. Those skills are need to develop for using the priceless, valuable human resources. Budget holds the key to the execution of Urban Forestry. Good inventory can provide for efficient budgeting stratiges through it's scientific analysis for the way of maximum benefits and minimum costs. Forest can be play a vital role for the aesthetic improvement and recreation in the city. This study suggests that the traditional sivicultural application not only improve the quality of scenic beauty and recreation but also the products of timber. So it is more needed to study for strong and scientific application to urban forest management.

• 유통과학연구
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• 제9권3호
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• pp.47-54
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• 2011

This paper presents exploratory research on consumer awareness and attitudesabout organic food, for which consumer demand continues to increase the paper also assesses consumers' organic food distribution channel preferences. By conducting a literature review, a case study has been carried out in order to glean customer behavior, market condition and typesof distribution channels, and development of specialty stores for organic foods. The early research indicates that consumer awareness and customer attitudes toward organic food are mostly positive however, organic food's high price, as well as a lack of organic food stores, cause a negative effect on consumers' purchase intention. Secondly, the U.S. organic food retail channel consists of such mainstream supermarket/grocery stores and leading natural and organic food supermarket chains as Whole Foods, Trader Joe's, and Sunflower Farmers Market. For the current retail distribution of organic food in Korea, off-line stores are composed of direct management stores and franchise chains. Most of the organic food retail distribution operates through the Internet shopping mall, and are commonly located at retail distribution centers as multi-channel, shop-in-shop stores. Moreover, unlike in the U.S., association and consumers' cooperatives (Co-Ops), and such other member-direct retail stores as Hansallim, iCOOP, Nature Dream,and online shopping malls, are all active in Korea. Thirdly, as a result of an analysis of the present state of the organic food retail channel, as well as building a case for organic food specialty stores, the distinctive featuresand rapid growth of such unique organic food stores as Whole Foods Market, or Trader Joe's successful downsizing strategies, as well as Sunflower Farmers Market low-price approach, show steady industry growth. Moreover, as a result of a case studyof such domestic representative organic food specialty stores as "Olga" and "Chorokmaeul," a similar management style to the United States' "Whole Foods Market" and "Trader Joe's," respectively, can be seen. Similar to the U.S. market, Korean organic food markets should also implement active retail distribution opportunities, allowing consumers to select from various diverse and differentiated choices. In order to accomplish this goal, it is necessary to prepare such measures as sustaining reasonable prices, securing various suppliers for unique products,and improving consumer trust through advertisement strategies that are suitable for each company's branding processes.

• 디자인학연구
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• 제18권1호
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• pp.59-68
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• 2005

시대변화에 따라 제품에 대한 소비자의 구매 결정기준과 제품 공급방법은 끊임없는 변화가 거듭되었다. 디지털기술을 응용한 on-line 시스템이 상품에 대한 정보를 전달하고 생산과 구매가 동시적으로 일어나는 시장체제가 형성하게 되었다. 그 결과 소비자 중심의 브랜드 구축이 중요한 과제가 되고 있다. 따라서 실증조사를 통하여 경제 사회 환경 변화에 따른 소비자의 의식구조를 파악하고, 이 변화에 따른 소비자의 구매결정 기준을 이해하고자 한다. 소비자의 구매태도를 만족, 선호, 재구입, 추천으로 기준을 설정하고, 이들 4개의 기준에 미칠 수 있는 브랜드 이미지의 요인들의 영향을 파악하였다. 브랜드 이미지의 효율적 형성을 위하여서 생성되는 소비자(고객) 중심의 브랜드 가치는 실증분석을 통하여 얻어진 결과를 보면 사회생활가치, 정서가치, 개성적가치 수용하여 브랜드이미지에 적용하는 것이 효과적인 것으로 나타났다. 연구결과에서 도출된 브랜드 이미지의 공통적 요인으로는 차별성가 고객 중심의 일관성 및 개성적, 감성적 요인들을 부각 시를 수 있는 행태로 브랜드 이미지화를 도모할 필요가 있다는 결과가 나타났다. 따라서 본 연구는 미래 지향적이고, 소비자에게 인지 연상되는 기능을 보다 효과적으로 증대시킬 수 있도록 고객 중심의 브랜드 창출을 위한 가이드라인을 제시하였다.

• 생태와환경
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• 제43권3호
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• pp.409-417
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• 2010

본 연구는 Pb의 농도와 노출 기간이 붕어(Carassius auratus) 조직의 미세구조와 생리적 변화에 미치는 영향을 조사하였다. 아가미, 뼈와 근육 조직에서 Pb의 축적 농도는 노출 40일에 증가하였다. 아가미 조직 내 Pb의 축적량은 다른 조직에 비하여 높았으며, 아가미, 뼈 및 근육 조직에서 노출기간이 길어질수록 증가하였다. Pb에 노출된 아가미, 뼈와 근육 조직의 항산화효소 활성은 아가미와 근육 조직에서 높았으며, 신장 조직에서 가장 낮은 활성을 보였다. 또한 항산화효소 중 superoxide dismutase의 활성은 대조군에 비해 2배 정도 증가하였으나, glutathion peroxidas의 활성은 매우 낮았다. Pb에 노출된 아가미 조직에서 점액세포는 수가 증가하였으며, 곤봉화와 부종이 이차새변에서 나타났다. 또한 40일간 Pb에 노출된 아가미 조직 내 미토콘드리아와 핵에서는 막의 손상이 관찰되었으며, 신장 조직 내 사구체는 수축되어 보우만 주머니의 공간이 넓게 관찰되었다. 이러한 결과로 보아 붕어 조직 이 장기간 고농도의 Pb에 노출이 되면 비정상적인 형태로 변형되며, 이에 따라 매우 유해한 영향을 받을 수 있을 것으로 생각된다.