• 건설안전기술
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• 통권52호
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• pp.58-66
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• 2011

This study presents an algorithm to select the best alternative plane among various bridge superstructure types (Steel box girder, Rational girder, PSC-I girder) using Value Engineering (VE). Economical efficiency, landscape, constructability, maintenance, stability, function of bridge superstructure were taken into consideration in the designing of bridge. Economical efficiency was evaluated for each alternative plan with optimal design considering Life Cycle Cost (LCC), Repair and rehabilitation histories and some factors were set to get reasonable results. In the application of Analytic Hierarchy Process (AHP), consistency of Pairwise Comparisons Matrix was evaluated and the best plan was determined.

• 한국건설관리학회:학술대회논문집
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• 한국건설관리학회 2007년도 정기학술발표대회 논문집
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• pp.13-18
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• 2007

보건복지부의 지원으로 건립하는 부산${\cdot}$경남 최초의 어린이전문병원 건립공사는 양산부산대학교병원과의 연계로 최고시설의 의료타운건립을 목표로 수행중이며 건설사업관리(CM)라는 체계적이고 과학적인 관리기법의 도입 및 적용을 통해 건설프로젝트의 비생산적이고 비효율적인 요소를 제거하여 생산성과 효율성을 향상시키고자 하는 것이다. 이에 본 연구에서는 어린이병원건립사업에 사업관리기법을 설계이전단계부터 턴키업체선정, 시공, 설계VE, PMIS구축, 유지관리단계의 사업 전(全)단계에 적용하여 발생한 효과와 분야별 기술자를 활용한 기본 및 실시설계VE를 통한 사업비 절감 및 공기단축 효과를 제시하고자 한다.

• 한국건설관리학회:학술대회논문집
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• 한국건설관리학회 2001년도 학술대회지
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• pp.422-427
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• 2001

건설프로젝트에서 현재 사용되고 있는 작업분류체계(Work Breakdown Structure)는 프로세스 내의 세부작업간 선·후행 관계의 불확실성과 작업의 불합리한 상호 연계성에 기인한 문제점을 내포하고 있다. 이를 해결하기 위해서 본 논문에서는 Work Structuring을 제시하여 프로세스간에 투명성을 부여하고 세부작업간의 간섭을 제거시켜 작업신뢰성을 향상할 수 있는 방안을 도출하였고 프로세스를 개선하기 위한 프로세스 디자인 다이어그램을 개발하였다. WS에 의한 프로세스 개선의 목적은 고객에게 가치를 창출시켜주면서 보다 신속하고 신뢰성 있는 작업 흐름을 만드는 것을 목적으로 하고 있으며 비가치 창출작업의 감소, 프로세스의 명료화 및 투명성 향상 등에 의의가 있다.

• Geomechanics and Engineering
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• 제24권3호
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• pp.237-251
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• 2021

The main purpose of this study is to investigate the performance of the proposed hybrid teaching-learning based optimization algorithm on the optimum design of reinforced concrete (RC) cantilever retaining walls. For this purpose, three different design examples are optimized with 100 independent runs considering continuous and discrete variables. In order to determine the algorithm performance, the optimization results were compared with the outcomes of the nine powerful meta-heuristic algorithms applied to this problem, previously: the big bang-big crunch (BB-BC), the biogeography based optimization (BBO), the flower pollination (FPA), the grey wolf optimization (GWO), the harmony search (HS), the particle swarm optimization (PSO), the teaching-learning based optimization (TLBO), the jaya (JA), and Rao-3 algorithms. Moreover, Rao-1 and Rao-2 algorithms are applied to this design problem for the first time. The objective function is defined as minimizing the total material and labor costs including concrete, steel, and formwork per unit length of the cantilever retaining walls subjected to the requirements of the American Concrete Institute (ACI 318-05). Furthermore, the effects of peak ground acceleration value on minimum total cost is investigated using various stem height, surcharge loads, and backfill slope angle. Finally, the most robust results were obtained by HTLBO with 50 populations. Consequently the optimization results show that, depending on the increase in PGA value, the optimum cost of RC cantilever retaining walls increases smoothly with the stem height but increases rapidly with the surcharge loads and backfill slope angle.

• 한국정밀공학회지
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• 제28권11호
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• pp.1297-1308
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• 2011

The light-weight design of UTM (Urban Transit Maglev)-02 car-body frames are performed, based on initial configuration. The thicknesses of fourteen sub-structures are defined as design variables and the loading condition is considered according to weight of sub-structures, electronic and pneumatic modules and passengers. For efficient and robust process of design optimization, objective function and constraints are approximated by response surface approximation. Structural analysis is performed at some sampling points to construct the approximated objective function and constraints composed of design variables. Design space is changed to find many optimal candidates and best optimal design can be found eventually. The Matlab Optimization Toolbox is used to find optimal value and sensitivity analysis about each design variable is also performed.

• 적정기술학회지
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• 제5권2호
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• pp.82-90
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• 2019

반응표면분석법(Response surface methodology, RSM)의 Box-Benhken Design (BBD) 모델을 사용하여, 350℃로 가열한 골탄의 수중 불소 흡착 조건을 최적화하였다. 최적화 변수로 수온, pH, 접촉시간, 초기불소농도를 선택하였고, Box-Behnken Design에 의한 29회의 매트릭스 실험값으로부터 2차 반응 표면식을 얻었다. 이 반응 모델식의 결정계수(R²)는 0.9249였고 모델의 p-value는 <0.0001로 나타나 실험 변수들이 흡착결과에 매우 유의미한 영향을 미친다는 것을 알 수 있었다. 반응 표면식에 의해 예측된 골탄의 불소 흡착 최적 조건은 수온 39.68℃, pH 6.25, 접촉시간 88.81 min, 초기불소농도 14.64 mgF/L이었으며 이때의 불소 흡착용량(adsorption capacity)은 6.46 mgF/g인 것으로 분석되었다.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2009년도 추계학술대회 논문집
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• pp.772-778
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• 2009

By rising the interests of the railroad, It has been required the research about railroad structure. And since 2000, the study about railway bridges caused by steel box railway bridges has been only 0.2%. So I was hard to find out about steel box railway bridges. In this study, I evaluate and analyze 4 types(KTX, Saemaeul, Mugunghwa, Freight) of dynamic caused by train loading, natural frequency and damping ratio, verticality deflection and verticality acceleration, end slope deflection, impact factor for dynamic characteristics analysis. natural frequency was measured 2.45Hz~3.34Hz and damping ratio revealed for 1.26~2.84%. Maximum verticality deflection(4.86mm) was sufficiently satisfied the design criteria(30.1mm), but in the case of verticality acceleration's respond, design criteria BRDM(Bridge Design Manual) & CTRL presentation derive rail limit value 0.35g be more than value 6 time recorded, maximum was measured 0.49g in 3 kinds of train(KTX, Saemaeul, Mugunghwa), except for Freight. Survey impact factor of Experiment bridge was 0.20 which is measured when the KTX(15:04) was driving. impact factor is enough contended with design criteria 0.29 which is presented in domestic railway design criteria and thoroughly guarantee the dynamic stability.

• 한국소음진동공학회논문집
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• 제19권12호
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• pp.1306-1314
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• 2009

By rising the interests of the railroad, It has been required the research about railroad structure. And since 2000, the study about railway bridges caused by steel box railway bridges has been only 0.2 %. So I was hard to find out about steel box railway bridges. In this study, I evaluate and analyze 4 types(KTX, Saemaeul, Mugunghwa, Freight) of dynamic caused by train loading, natural frequency and damping ratio, verticality deflection and verticality acceleration, end slope deflection, impact factor for dynamic characteristics analysis. natural frequency was measured 2.45 Hz~3.34 Hz and damping ratio revealed for 1.26~2.84 %. Maximum verticality deflection(4.86 mm) was sufficiently satisfied the design criteria(30.1 mm), but in the case of verticality acceleration's respond, design criteria BRDM(bridge design manual) & CTRL presentation derive rail limit value 0.35 g be more than value 6 time recorded, maximum was measured 0.49 g in 3 kinds of train(KTX, Saemaeul, Mugunghwa), except for Freight. Survey impact factor of Experiment bridge was 0.20 which is measured when the KTX(15:04) was driving. impact factor is enough contended with design criteria 0.29 which is presented in domestic railway design criteria and thoroughly guarantee the dynamic stability.

• Structural Engineering and Mechanics
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• 제45권5호
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• pp.643-654
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• 2013

Optimum cost design of columns subjected to axial force and uniaxial bending moment is presented in this paper. In the formulation of the optimum design problem, the height and width of the column, diameter and number of reinforcement bars are treated as design variables. The design constraints are implemented according to ACI 318-08 and studies in the literature. The objective function is taken as the cost of unit length of the column consisting the cost of concrete, steel, and shuttering. The solution of the design problem is obtained using the artificial bee colony algorithm which is one of the recent additions to metaheuristic techniques. The Artificial Bee Colony Algorithm is imitated the foraging behaviors of bee swarms. In application of this algorithm to the constraint problem, Deb's constraint handling method is used. Obtained results showed that the optimum value of numerical example is nearly same with the existing values in the literature.

• Computers and Concrete
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• 제10권3호
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• pp.295-306
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• 2012

Optimum cost design of a simply supported reinforced concrete beam is presented in this paper. In the formulation of the optimum design problem, the height and width of the beam, and reinforcement steel area are treated as design variables. The design constraints are implemented according to ACI 318-08 and studies in the literature. The objective function is taken as the cost of unit length of the beam consisting the cost of concrete, steel and shuttering. The solution of the design problem is obtained using the artificial bee colony algorithm which is one of the recent additions to metaheuristic techniques. The artificial bee colony algorithm is imitated the foraging behaviors of bee swarms. In application of this algorithm to the constraint problem, Deb's constraint handling method is used. Obtained results showed that the optimum value of numerical example is nearly same with the existing values in the literature.