• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2006년도 추계 학술발표회
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• pp.515-520
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• 2006

Yano method had been used in predicting the settlement of self-weight consolidation of dredged soil in the construction of reclamating the dredged soil. Its estimation was found to show some different results from field measurements. The numerical analysis with PSDDF was peformed find such differences, considering the effect of desiccation on the consolidation during the remaining time after reclamation. For the parametric study, numerical analyses with/without consideration of desiccation were carried out with changing the conditions of desiccation such as the number of placing the fill and the time period between each placement. As results of analysis, estimations about consolidation settlement and distribution of water contents with consideration of desiccation was in good agreements with field measurements. It was also found that the number of placing the fill and the time period between each placement did not affect the behavior of self-weight consolidation as much as the effect of desiccation.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2000년도 가을 학술발표회논문집(I)
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• pp.705-710
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• 2000

Recently, use of sea-sand as fine aggregates in reinforced concrete structures is increasing because of lacking of supply due to destructive of environment caused by obtaining and exhausting of resource. It rise up issue, some field reconstruction, interrupted construction works occurring to the trouble on the site because sometimes engineer does not agree to use of corroded bar, even slighly corroded. This study investigates the properties of bond strength and the structural behavior of corroded bars before and after placement. The purpose of the study is to present the database estimating degree of damaged bond strength according to corrosion level and deciding on whether using corroded bars or not.

• International Journal of Concrete Structures and Materials
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• 제7권2호
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• pp.165-174
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• 2013

Portland cement concrete exposed to high temperatures during mixing, transporting, casting, finishing, and curing can develop undesirable characteristics. Applicable requirements for such the hot weather concrete differ from country to country and government agencies. The current study is an attempt at evaluating the hardened properties of the concrete exposed to hot weather in fresh state. First of all, this study reviews the current state of understanding and practice for hot weather concrete placement in US and then roadway sites with suspected hot weather concrete problems were investigated. Core samples were obtained from the field locations and were analyzed by standard resonance frequency analysis and the boil test. Based on the results, there does not appear to be systematic evidence of frequent cracking problems related to high temperature placement. Thus, the suspicious deteriorations which are referable to hot weather concreting would be due to other factors.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2005년도 추계 학술논문 발표대회
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• pp.85-88
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• 2005

This study investigates influence on concrete adding beverage or detergent, by work man's mistakes during concrete placement in field. Overall, concrete adding beverage or detergent does not affect slump and air content, compared with control concrete. However concrete adding detergent resulted in significantly higher air content, due to inter facial activation ingredient. For the properties of setting time, concrete adding lactic acid beverage indicated the longest retarding properties, next was coffee and soft drink in order. Compressive strength of concrete, which retarded setting time. exhibited slightly improved value at 7 and 28 days respectively, while that of concrete adding detergent significantly decreased, due to higher air content.

• Journal of Electrical Engineering and Technology
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• 제5권1호
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• pp.79-102
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• 2010

This paper presents exhaustive review of various methods/techniques for coordinated control between FACTS controllers in multi-machine power systems. It also reviews various techniques/methods for optimal choice and allocation of FACTS controllers. Authors strongly believe that this survey article will be very much useful to the researchers for finding out the relevant references in the field of placement and coordination of FACTS Controllers.

• 한국가스학회지
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• 제17권2호
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• pp.59-69
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• 2013

본 연구에서는 가스전의 추가 생산정 위치선정을 위해 고속의 연산이 가능한 인공신경망을 이용하여 저류 전산시뮬레이터를 개발하였다. 입출력자료와 알고리즘을 설계하였으며, 개발한 시뮬레이터를 이용하여 가스전의 추가 생산정 위치선정을 위한 연구를 수행하였다. 입력값은 생산시간, 생산정간 상관관계, 추가 생산정 위치좌표, 생산성 잠재력, 함수적 연관관계, 저류층 압력으로 구성하였으며, 출력값은 생산량과 함께 공저압력을 동시에 사용하였다. 20가지의 생산정 위치 시나리오에 대해 학습을 수행한 결과, 생산량의 상관계수 값은 0.99, 공저압력은 0.98로 상관관계가 매우 높은 것으로 확인되어 인공신경망 시뮬레이터의 타당성이 검증되었다. 가스전에서 최대공급계약량 유지시점을 산출함으로써 생산정 위치에 따른 생산성을 분석하였다. 그 결과 시나리오 C-1이 최대공급계약량 유지기간이 가장 짧았으며, 시나리오 A-1이 가장 오랫동안 유지시킬 수 있는 것으로 산출되었다. 결론적으로, 시나리오 A가 생산성에 영향을 받는 인자를 포함한 시나리오 B, C보다 최대 21% 더 최대공급계약량을 유지시킬 수 있는 것으로 확인되었다. 따라서 생산성에 영향을 미치는 요소를 종합적으로 고려하여 생산정의 위치를 선정해야 생산량을 극대화 할 수 있다. 본 인공신경망 시뮬레이터를 이용 시 생산기간동안 생산량과 공저압력 변화를 동시에 비교 분석하는 것이 가능하여 다양한 최적화 모델에 전위모델로 사용하는 것이 가능하다.

• 농촌계획
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• 제20권1호
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• pp.77-89
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• 2014

This study intends to establish a system to investigate and analyze various impacting factors to Rural Housings such as the relationship of characteristics of Rural Housings located in a Rural Village to the Village and a Unit Housing, to the External and Internal Spaces inside the Unit Housing and the Village, and to Living Characteristics of the Residents and Space from an integrated point of view. The results of this study are largely summarized as following four kinds. Rural Housing Survey System can be largely classified into three stages, and they are a Preliminary Survey, Basic Survey and In-depth Survey. Along with these, the scope of the survey contents can be divided into a survey result by a unit of village, of land, of housing, and of resident's opinion survey. Secondly, the surveys by village unit are on location properties, Village Identity, Street Network, Land Use, Landscape Features and Public Facilities, and consist of Literature, Discussion and Field Survey. Thirdly, the land Unit Surveys are on a Driveway, Gate Location, Housing Placement, Outer Space Design in a Yard and Outer Space Use Characteristics, and consist of Questionnaire and Field Surveys. For the fourth, the Housing Unit Surveys are on an Internal Space Design and Placement, and consist of Questionnaire and Field Surveys. Finally, the Resident Questionnaire Survey consisted of Entire Discussion Survey and a Household one, and then the Entire Survey was on the Village's History, Village's Characteristics, Cultivation Characteristics and Community Activities while an individual one was on Main Living Characteristics, Satisfaction and Utilization Characteristics.

• Smart Structures and Systems
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• 제24권6호
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• pp.709-721
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• 2019

This paper investigates the framework of vision-based dense displacement and strain measurement of miter gates with the approach for the quantitative evaluation of the expected performance. The proposed framework consists of the following steps: (i) Estimation of 3D displacement and strain from images before and after deformation (water-fill event), (ii) evaluation of the expected performance of the measurement, and (iii) selection of measurement setting with the highest expected accuracy. The framework first estimates the full-field optical flow between the images before and after water-fill event, and project the flow to the finite element (FE) model to estimate the 3D displacement and strain. Then, the expected displacement/strain estimation accuracy is evaluated at each node/element of the FE model. Finally, methods and measurement settings with the highest expected accuracy are selected to achieve the best results from the field measurement. A physics-based graphics model (PBGM) of miter gates of the Greenup Lock and Dam with the updated texturing step is used to simulate the vision-based measurements in a photo-realistic environment and evaluate the expected performance of different measurement plans (camera properties, camera placement, post-processing algorithms). The framework investigated in this paper can be used to analyze and optimize the performance of the measurement with different camera placement and post-processing steps prior to the field test.

• 한국응용곤충학회지
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• 제16권3호
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• pp.155-161
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• 1977

살충제의 액상근부처리(Root zone-liquid)와 캡슐근부처리(Root zone-capsule)에 의한 수도해충 방제효과를 검토하고 살충제의 새로운 사용방법을 개발하기 위해 pot 및 포장시험을 실시하였다. A. Pot 시험 이앙 5일후 ha당 1kg(a.i)와 2kg(a.i) 1회 시용수준에서 Carbofuran, Omethoate의 액상근부처리(Pipett에 의함) Carbofuran, Disysteon의 캡슐 근부처리 및 Carbofuran, Disyston, Diazinon의 수면처리를 하여 이화명충, 애멸구, 벼멸구 방제효과를 검토하였다. 1. 약제처리후 10일, 20일, 30일에 이화명충 부화유충을 접종하고 20일후 살충율과 심고경을 조사한 바 Carbofuran 액상근부처리와 Capsule 근부처리는 약제처리후 30일까지 계속 이화명충의 방제효과가 좋았다. Carbofuran 수면시용은 약제처리후 10일까지는 방제효과가 있었으나 그 후는 낮았으며 그밖에 약제들은 이화명충 방제효과가 낮았다. 2. 약제처리후 17일에 애멸구, 벼멸구 성충을 접종하여 살충율을 조사한 바 Carbofuran 액상근부처리와 캡슐 근부처리는 살충력이 비교적 높았으나 그밖에 약제 또는 처리에서는 거의 살충력을 기대할 수 없었다. 3. Carbofuran 액상근부처리와 캡슐근부처리는 Carbofuran 수면시용에 비하여 해충방제효과가 정확하고 잔 효력이 월드이 좋았다. B. 포장시험 이앙 5일(A-포장)과 18일 (B-포장)후에 ha당 1kg과 2kg(a. I)을 각각 1회 시용수준에서 Carbofuran, Omethoate 액상근부처리 (Liquid applicator에 의함), Carbofuran 캡슐 근부처리를 실시하였고 Carbofuran 캡슐 근부처리를 실시하였고 Carbofuran과 Diazinon은 같은 수준에서 각각 이화명충 제1화기에 1회, 2화기에 1회 수면처리한 다음 이화명충에 의한 심고경율, 백수경율, 애멸구의 밀도를 조사였다. 1. Carbofuran, Omethoate 액상근부처리에 비하여 캡슐 근부처리는 이화명충, 애멸구방제효과가 월등히 좋았고 Omethoate보다는 Carbofuran의 방제효과가 좋았다. 2. Carbofuran 1회 액상근부처리는 Carbofuran 2회 수면시용과 대등한 수도해충의 방제효과가 있었다. 3. A포장에서 보다 B포장에서 이화명충 방제효과가 좋았는데 그것은 B포장에서의 약제처리시기가 이화명충 방제적기에 해당하기 때문인 것 같다. 4. Carbofuran 1회 근부처리는 수도 전 생육기간에 걸친 수도해충방제가 가능한 것으로 보였다.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 1989년도 가을 학술발표회 논문집
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• pp.69-72
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• 1989

It is widely recognized that the strength of reinforced concrete members has characteristics of random variations due to the variability of the mechanical properties of concrete and steel, the dimensional error as well as incorrect placement of reinforcing bars. In those sources of randomness, variations in concrete strength may be the one affecting the strength of R.C. members most. The concrete strength is usually assumed to have large uncertainty due to the variations in many factors, such as material properties, proportions of the concrete mix, methods of mixing, transporting, placing and curing, etc. In this study, the random characteristics inherent in the strength of field-cast concrete have been examined based on the data collected by testing standard cylinders made of field-cast concrete and cured under in-situ condition.