• 한국강구조학회 논문집
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• 제13권5호
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• pp.493-502
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• 2001

본 연구에서는 아직 설계법이 정립되지 않은 리브로 보강된 RBS 철골모멘트 접합부의 내진설계법을 등가 스트럿 모델에 의거하여 제시하였다. 종종 엔지니어가 리브를 사용하여 철골모멘트접합부의 내진성능을 높이고자 할 경우 고전 휨이론에 의거하여 리브와 보로 구성된 일체단면의 단면2차모멘트로서 그루브 용접부의 인장응력도 예측하려 하는데 이는 타당치 않다. 리브접합부의 응력전달 메커니즘은 고전 휨이론에 의한 메카니즘과는 전혀 다르다. 즉 리브는 고전 휨이론에 의한 기대와는 달리 리브의 대각선 기울기 방향으로 스트럿 거동을 보인다. 필자는 이 같은 점에 주목하여 리브를 스트럿 요소로 파악하여 리브 접합부의 설계에 활용될 수 있는 등가 스트럿 모델을 이미 제시한 바가 있다. 본 연구에서는 이 등가 스트럿 모델을 기초로 리브접합부의 실용설계에 활용될 수 있는 단계별 설계절차를 제안하였다.

• 콘크리트학회지
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• 제8권3호
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• pp.187-195
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• 1996

콘크리트 구조요소의 비선형거동을 예측하기 위하여 압축응력장 이론의 기본개념인 압축강도 연화 현상, 거시적 및 회전균열 모델을 고려한 유한요소해석이 제시되었다. 수치해석상의 효율성 및 최대하중 이후의 거동에 주안점을 두어 초기재료 강성을 채택한 변위증분법 논리 및 빠른 수렴을 위한 Over-Relaxation 방법이 Isoparametric계의 8-Node 요소에 포함.유도되었다. 상기에 근거하여 제작된 비선형 프로그램, NASCOM은 다조하중을 지지하는콘크리트 구조요소의 내력, 변형특성, 균열 분포 상황 및 보강근의 항복 분포를 예측하는데 사용할 수 있다. NASCOM의 성능을 검토하기 위하여 이러한 목적에 빈번히 사용되는 Bhide의 패널(PB21) 및 Leonhardt의 춤이 큰보에 대한 해석이 실시되었다. 패널에 대한 해석결과는 대체로 변형이력 및 강도가 강한 거동을 나타내는 반면에, 춤이 큰보에 대해서는 변형이력이 유연한 거동을 나타내고있어, 향후 보다 정확한 결과를 예측하기 위해서는 콘크리트의 인강강화 및 압축강도 연화현상에 대하여 좀더 향상된 재료모델의 고려가 필요한 것으로 판단되었다.

• 콘크리트학회논문집
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• 제17권3호
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• pp.343-351
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• 2005

본 논문에서는 FRP 외부 부착공법으로 전단 보강된 철근콘크리트 보의 전단강도 예측 모델을 제안하였다. 제안된 모델은 전단 균열각과 전단 경간비와 같은 주요한 설계인자를 고려할 수 있도록 하였다. 제안된 모델의 주요고려사항은 ]nP로 전단 보강된 보의 일반적 파괴 형태인 부착파괴에 대한 전단력 산정이다. 또한 제안된 모델은 기존의 수정 소성이론에 근거한 crack sliding model을 이용하였으며, 아치작용계수를 도입함으로써, 전단 경간비의 영향을 최소화하였다. 최종적으로 본 전단강도 예측 모델을 적용한 해석결과를 실험결과와 비교$\cdot$검증하였으며, 본 제안된 예측 모델이 실험결과와 상당히 일치하는 것을 확인하였다.

• 콘크리트학회논문집
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• 제14권2호
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• pp.231-238
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• 2002

콘크리트 교량 바닥판은 건조수축 및 온도변화 등에 의하여 초기 1차균열이 발생하고, 사용기간 동안 반복되는 차량하중의 크기와 철근 간격 등에 의하여 초기 균열이 이방향 균열로 점차 발전하게 된다. 그러나 현재 사용되고 있는 대부분의 균열 예측식이 일방향 부착-슬립이론에 기초하고 있기 때문에 철근과 보강재의 간격에 따라 변화되는 교량 바닥판의 균열폭을 예측하고 보강된 바닥판의 사용성을 평가하기에는 많은 어려움이 있다. 따라서 본 연구에서는 시험결과에 기초하여 성능향상된 바닥판의 균열 메카니즘을 구명하였으며, 이로부터 사용성을 평가할 수 있는 새로운 균열예측식을 제안하였다. 제안된 균열예측식은 기존 균열식에 비하여 예측결과가 우수한 것으로 나타났으나, 철근 항복 이후 철근과 보강재의 변형률이 급격히 증가할 때 오차범위가 커지는 것으로 나타나 추가적인 연구가 필요한 것으로 판단된다. 따라서 보다나은 균열예측을 위해서는 피로 하중하에서의 철근 항복이후에 대한 추가적인 연구가 필요한 것으로 판단된다.

• Computers and Concrete
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• 제1권3호
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• pp.325-354
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• 2004

Slabs in buildings and bridge decks, which are restrained against lateral displacements at the edges, have ultimate strengths far in excess of those predicted by analytical methods based on yield line theory. The increase in strength has been attributed to membrane action, which is due to the in-plane forces developed at the supports. The benefits of compressive membrane action are usually not taken into account in currently available design methods developed based on plastic flow theories assuming concrete to be a rigid-plastic material. By extending the existing knowledge of compressive membrane action, it is possible to design slabs in building and bridge structures economically with less than normal reinforcement. Recent research on building and bridge structures reflects the importance of membrane action in design. This paper describes the finite element modelling of membrane action in reinforced concrete slabs through optimisation of a simple concrete model. Through a series of parametric studies using the simple concrete model in the finite element simulation of eight fully clamped concrete slabs with significant membrane action, a set of fixed numerical model parameter values is identified and computational conditions established, which would guarantee reliable strength prediction of arbitrary slabs. The reliability of the identified values to simulate membrane action (for prediction purposes) is further verified by the direct simulation of 42 other slabs, which gave an average value of 0.9698 for the ratio of experimental to predicted strengths and a standard deviation of 0.117. A 'deflection factor' is also established for the slabs, relating the predicted peak deflection to experimental values, which, (for the same level of fixity at the supports), can be used for accurate displacement determination. The proposed optimised concrete model and finite element procedure can be used as a tool to simulate membrane action in slabs in building and bridge structures having variable support and loading conditions including fire. Other practical applications of the developed finite element procedure and design process are also discussed.

• 대한한의학회지
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• 제18권2호
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• pp.187-198
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• 1997

The degree of KAP study on Chinease traditional medicine and doctor was examined with some chinease living yenbian district(延邊) from July 1st to August 30th in 1996. The result of the study for predicting health and ill patterns runs as fellows. 1. It is understand to strength and variety about role of chinease traditional medicine doctors and the curable disease. 2. Although most patients go to chinease traditional medicine clinic for the purpose of medicine herbs in package, acupuncture and industry-made pharm, they think the medical fee a little high(70.6%). 3. The 66.7% of respondents recognize chinease traditional medicine doctors as a profession and others think them only abundant works ; therefore it is rather low to ink chinease traditional doctors a profession. 4. Most respondents think that chinease traditional medicine should improved in the inside ; such as scientific reinforcement of theory, lack of univerality, improvment and enlargement of insurance, unkindness, shortage of publicity, dropped equipment, system of medical specialist, lack of integration with westem medicine, exact diagnosis and confidence of remedy, and low efficacy, etc. 5. Chinease likes more experienced-traditional doctor than beginner(78.3%) 6. The policy of korean government against 100 herbal prescription right by western pharmacy has taken the negative recognition(74.6%), 7. The degree that acknowleges of chinease traditional medicine through thease basic contents is average 47.3 mark. To be brief, although the step of the recognition and attitude of oriental medicine is less or very affirmative aspect, actully considerable positive factors is in the last chosen step. In conclusion KAP study connected chinease traditional medicine and doctor has very much postive factors.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2008년도 춘계 학술논문 발표대회
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• pp.83-86
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• 2008

The concrete used most in construction materials. There is an overcrowded iron dimensions use of the concrete at time of the other concrete theory on the reinforcing rod back which did congestion and compares it with this, and there are more few dimensions of the aggregate than concrete, and quantity of aggregate passage is superior in mortar than concrete. If a volume rate of the aggregate writes mortar than concrete against this, therefore, unit amount increases, and quantity of paste increases and quantity of dry shrinkage than increase concrete. However, I let I regulate lay priest distribution of the aggregate, and the results rates increase and reduce unit amount and decrease quantity of dry shrinkage, and separation resistance and the gap passage characteristics are judged because it can be it in a substitute document of very superior concrete. I came to carry out the study that I watched to let I was useful a little more and do the improvement repair of a become building wall body, a basement pillar and repair reinforcement of the assistant in the reinforcing rod back, the old age when I made congestion here. I regulated lay priest distribution of the aggregate in the study and regulated substitution rate of the aggregate (40%, 50%, 60%) and divided W/C 30%, 40% standards and produced mortar and I compared quantity of air by this, slump, compression robbery and showed it this time.

• 대한예방한의학회지
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• 제1권1호
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• pp.27-41
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• 1997

The degree of KAP study on oriental traditional medicine was examined with some korean from July 1st to August 30th in 1996. The result of the study for predicting health and ill patterns runs as fellows. 1) It is too weak to understand and adertise oriental traditional medicine doctors and the curable disease; moreover cured diseases rather preponderate. 2) Although most patients go to oriental traditional medical clinic for the purpose of medical herbs in package and acupuncture, they think the medical fee a high expensive. 3) The 77.9% of respondents recognize oriental traditional medical doctors as a profession and others think them only abundant workers; therefore it is rather low to think oriental traditional doctors a profession. 4) Most respondents ink that oriental traditional medicine should improved in the inside; such as the expensive fee, scientific reinforcement of theory, lack of univerality, improvement and enlargement of insurance, unkindness, shortage of publicity, dropped equipment, system of medical specialist, lack of integration with western medicine, exact diagnosis and confidence of remedy and low efficacy, etc. 5) The struggle against the government (1995-1996 about herbal prescription right by western pharmacy) has taken the change of affirmative recognition. 6) The degree that acknowleges of oriental traditional medicine through these basic contents is average 61.65 mark. To be brief, although the step of recognition and attitude of oriental me야cine is very affirmative aspect, actually considerable difficult factors is in the last chosen step.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2010년도 추계 학술발표회 2차
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• pp.21-31
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• 2010

Although it is important to reflect the accurate information of the ground condition in the tunnel design, the analysis and design are conducted by limited information because it is very difficult to get it practically on considering various geography and geotechnical condition. So construction management of information concept is required to manage immediately on the field condition because it is very time-consuming to establish the countermeasure of underground reinforcement and the pattern change of Bo. Therefore, when construction is on tunnel area, examination of accurate safety and prediction of behavior is performed to overcomes the limit of predicting behavior by using Artificial Neural Network(ANN) in this study. Firstly, the field data was secured. Secondly, suitable structure was made on multi-layer perceptrons among the ANN. Thirdly, learning algorithm-propagated applies to ANN. The data for the learn of field application using ANN was used by considering impact factors, which influenced the behavior of tunnel, and performing credibility analysis. crown displacement, spring displacement, subsurfacement, and rock bolt axial force are predicted at the tunnel construction and on-site application was confirmed by using ANN from analyzing and comparing with measurement value of on-site. In this study, the data from Seoul Highway $\bigcirc\bigcirc$ tunnel section was applied to the ANN Theory, and the analysis on the investigate value and the reasoning for the value associated with field application was performed.

• 농업과학연구
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• 제45권2호
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• pp.298-307
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• 2018

The aim of this study was to enhance the value of the chestnut industry by analyzing the value chain structure. Based on the value chain theory, it is divided into primary activities and support activities. Thus, in total, 27 subjects from Gongju, Buyeo, and Cheongyang were interviewed and self-administered questionnaire. Regarding the value chain structure of the chestnut industry, the primary activities consisted of production followed by cultivation and storing, sorting and packaging, transportation and marketing sales. The support activities were divided into production infrastructure, policy, R&D, and systematization. The primary activities are able to maximize profits through cost reductions. The production was divided into general and environmentally friendly cultivation. Depending on the labor force, it is family-centered labor. However, the installation of harvest nets depends on a hired labor force (40 - 60%) such that it would be necessary to have a mechanized harvest to replace the manpower for the cost reduction. Transportation, marketing sales, and backdoor selling (38.1%) were higher than the existing channels (31.0%) using the National Agricultural Cooperative Federation. The enhancement of value could be created by maximizing profits through the reinforcement of the links between each subject. The production showed strong connections with cultivation/storing, sorting/packing, and backdoor selling and the National Forestry Cooperative Federation. The processing stage is a very simple structure, it would be necessary to have R&D and to support promotions, infrastructure, machines, and sales increases, which should be expanded by connections with other industries like the food industry.