• 대한토목학회논문집
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• 제40권1호
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• pp.77-85
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• 2020

현재 국내의 대형 인프라시설물의 유지관리를 위해 생애주기비용분석 방법을 도입하고 있다. 그러나 시설물의 위치 및 주변환경 등의 조건을 반영한 유지관리 모델을 적용하는 사례가 많지 않다. 적절한 유지관리 전략을 수립하기 위해서는 시설물의 환경조건을 반영한 비용예측, 열화모델, 불확실성을 반영한 의사결정모델이 수립되어야 한다. 본 연구에서는 발전구조물에 적용되는 도장 사양을 대상으로 유지관리 방법과 판단기준에 따라 사용자의 의사결정에 따른 장기적인 비용 계획 및 관리를 할 수 있는 경제성 분석 모델을 개발하였다. 경제성 분석 모델의 적용을 위하여 도장열화실험을 통하여 도장의 성능을 평가하였으며, 제안 경제성 분석 모델에 적용하여 각각의 적용도장 사양(우레탄, 폴리실록산, 불소)에 따른 경제성 분석결과를 확인하였다. 본 연구에서는 도장의 성능보다 보수 주기의 선정과 개발 모델을 적용한 평가 방법을 제시한 결과로 도장에 국한되지 않더라도 유지관리 방안 수립 시 보수 주기 등을 위한 기초적인 자료로 활용을 기대할 수 있을 것으로 판단된다.

• 한국구조물진단유지관리공학회 논문집
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• 제20권6호
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• pp.1-9
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• 2016

본 논문은 교량의 예방적 유지관리 효과를 생애주기비용 절감 측면에서 분석 하였다. 예방적 유지관리는 현재 실시되고 있는 대응적 유지관리 전략과 대비 되는 유지관리 전략으로 교량의 열화지연을 통해 궁극적으로는 교량의 사용수명을 연장 시키며 생애주기비용을 절감시키는 유지관리 전략이다. 이러한 예방적 유지관리 효과를 분석하기 위해 교량의 공용연수에 따른 건전도 점수 변화 모델과 FHWA 자료를 바탕으로 한 국내 고속도로 교량의 건전도 점수에 따른 보수 보강 비용 모델을 제시 하였다. 제시한 복수의 모델과 국내외 참고 문헌을 바탕으로 제안된 예방적 유지관리 항목(청소와 도장)의 비용과 주기를 활용하여 사용수명 100년까지의 표준교량($1,730m^2$/교량) 당 생애주기 비용과 향후 20년간의 고속도로 총 유지관리 비용을 산정 하였다. 분석 결과 100년간 예방적 유지관리 활동으로 인해 교량 당 5억원의 절감효과를 볼 수 있으며 현재 예방적 유지관리 활동을 실시할 경우 20년 후(2035년)에는 총 1,837억원, 즉 연간 약 92억원의 비용 절감효과를 볼 수 있는 것으로 분석 되었다.

• 한국재난정보학회 논문집
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• 제16권2호
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• pp.276-290
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• 2020

연구목적: 국내 항만시설의 건설역사는 100년 이상 되었으며 최근 까지 현대적 시설이 지속적으로 건설되어 확장되고 있다. 그러나, 해양환경의 변화 및 물동량의 증가 등으로 초기 건설당시의 요구 성능조건을 유지하기는 쉽지 않다. 특히, 사용년수가 오래된 항만구조물의 경우, 선박의 대형화와 사용빈도 증가, 자연재해의 규모 증가등으로 안전성능과 기능관리가 매우 중요해져 가고 있다. 연구방법: 이에 본 연구는 항만시설의 구조형식별 상태변화를 조사하고 이를 기반으로 성능개선 및 수명연장활동에 기여하는 보수보강활동과 그 이력을 분석하였다. 연구결과: 항만시설 유지관리전략수립에 활용 가능한 성능개선비용(CAPEX)과 수선유지활동(OPEX)을 구별하고 이를 통한 유지관리전략수립에 활용 가능한 비용모델을 제시하였다. 결론: 이러한연구는 향후 시설물 중장기 투자의사결정에 큰 기여를 할 것으로 기대된다.

• 한국도로학회논문집
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• 제16권6호
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• pp.159-167
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• 2014

PURPOSES : The purpose of this study is to analyze the requirements of the road traffic safety moderator robot when road repairing. The road traffic safety moderator robot is road traffic safety equipment and to conversions mechanical engineering and IT when road repairing. METHODS : The study used AHP based on the survey from road repair related expert that field engineers, design engineers, public officials and professors. The survey used paired comparison. The survey items were safety, convenience and economics. The safety is classified as visibility or efficiency, the convenience is classified as utility or mobility and the economics is classified as initial investment cost or maintenance $ management cost. The survey alternatives were the road traffic safety moderator robot, traffic regulation by human, traffic regulation by mannequin and traffic signs. The software for AHP is Expert Choice 2000. RESULTS : The results of AHP analyze, the weighted value of safety was analyzed with the highest at 0.488 of survey items. The weighted value of convenience was analyzed at 0.295, the weighted value of economics was analyzed at 0.218. The results of the road traffic safety moderator robot, the weight value of efficiency and utility were analyzed with the highest at 0.284 and 0.259 of alternatives. The weighted value of initial investment cost and maintenance & management cost were analyzed with the lowest at 0.203 and 0.211 of alternatives. The consistency test results of each items, null hypothesis is rejected because the CR values were 0.000 respectively. Therefore, the study results are consistency. CONCLUSIONS : The result of this study, overall value of the road traffic safety moderator robot came off second-best of other alternatives. The road traffic safety moderator robot has been received highest praise by the result of the study as good road traffic safety equipment when road repairing because the weighted values of efficiency and utility were analyzed with the highest of survey items. The efficiency mean securing safety and the utility mean practical assistance when road repairing. The results of this study showed that the road traffic safety moderator robot will effective for traffic safety when road repairing. economics and visibility are that supplementation of the road traffic safety moderator robot because the weighted values of economics and visibility were analyzed with the lowest of survey items. The consistency test results are consistency because the CR values were 0.000 respectively.

• 한국조경학회지
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• 제40권1호
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• pp.81-91
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• 2012

본 연구는 조경공사 하자판례를 조사하여 하자소송의 일반적 분석, 공종별 판결 결과, 하자유형별 판결결과를 분석하고 하자분쟁을 완화하기 위한 조경공사 하자처리 개선방안을 제안하는 것이다. 본 연구의 주요 결과는 다음과 같다. 1. 2000년대 들어 조경공사와 관련된 하자소송이 증가하고 있으며, 소송 기간은 1심의 경우 603일, 2심의 경우는 550일로 나타나 사용자와 시공자 모두에게 심각한 시간적 경제적 손실을 초래하고 있다. 2. 감정금액 대비 인용금액이 1심의 경우 52.0%, 2심의 경우 57.3%, 전체적으로는 53.6% 수준으로 감정금액이 과다하게 책정되는 경향이 있는 것으로 나타났다. 3. 공종별 하자판결 결과는 조경수목식재가 전체 하자 발생 공종의 75%에 달하여 주요한 쟁점으로 나타났으며, 사용자인 원고의 승소율이 77%에 달하여 시공자들의 하자이행에 심각한 부담으로 나타났다. 4. 하자유형별 판결 결과에서는 사용자의 유지관리 부실로 인한 하자가 28%를 차지하고 시공자인 피고의 승소율이 64%로 높게 나타나 사용자의 유지관리 책임이 중요하게 부각되었다. 이러한 문제를 개선하기 위해서는 하자를 줄일 수 있도록 정확한 시공을 하고, 적절한 유지관리를 시행하도록 해야 하며, 부적기 식재 및 천재지변에 의한 피해 등 하자면책규정, 공종별 하자판정기준, 하자이행절차 등을 포함하는 조경공사 하자판정 및 처리기준을 마련해야 한다.

• 한국정밀공학회지
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• 제24권9호
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• pp.44-51
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• 2007

There are many methods to assemble various parts of a product, and one of them is the bolting system widely used in a industrial field due to the merits; easiness to obtain strong tightening force, simplicity of assemble or disassemble in order to repair, substitution or cleaning, and so on. But this bolting system needs attachments not to let a bolt loose and they are an important factor to cost a great deal. In this study, some equations are suggested and FE analyses are carried out to verify the cause of the bolt looseness occurring in the tightening process. And because the number of bolts in the bolting system has been decided by empirical know-how of designers in the field, safety rate in the plate type heat exchanger is often too high. Therefore the equations to decrease in quantity are suggested in consideration of the relationship between a critical shearing force acting on the screw and a normal force acting on the cooling plate by the working fluid.

• 한국건축시공학회지
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• 제5권3호
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• pp.125-129
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• 2005

The waterproofing in slab and wall of underground structure, have a couple of construction methods which are inside waterproofing methods for inner surface, and outside waterproofing methods for out wall and slab surface waterproofing. In resent years, however, it has been adapted the inside waterproofing construction method, as increasing of construction expenses cost and low workability and technology, nevertheless, outside waterproofing has set a most high value construction method. In inside waterproofing construction method, it is difficult to repair and assure durability and safety for concrete which has direct water-press. So, It is necessary for adopt the outside waterproofing method. For that reasons, this study based on the application for outside waterproofing method on the under ground structure, to more increase durability, to introduce mono adhesive sheet waterproofing materials. as considering chemical, physical properties.

• Clinical and Experimental Pediatrics
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• 제57권8호
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• pp.337-344
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• 2014

Inherited bone marrow failure syndrome (IBMFS) encompasses a heterogeneous and complex group of genetic disorders characterized by physical malformations, insufficient blood cell production, and increased risk of malignancies. They often have substantial phenotype overlap, and therefore, genotyping is often a critical means of establishing a diagnosis. Current advances in the field of IBMFSs have identified multiple genes associated with IBMFSs and their pathways: genes involved in ribosome biogenesis, such as those associated with Diamond-Blackfan anemia and Shwachman-Diamond syndrome; genes involved in telomere maintenance, such as dyskeratosis congenita genes; genes encoding neutrophil elastase or neutrophil adhesion and mobility associated with severe congenital neutropenia; and genes involved in DNA recombination repair, such as those associated with Fanconi anemia. Early and adequate genetic diagnosis is required for proper management and follow-up in clinical practice. Recent advances using new molecular technologies, including next generation sequencing (NGS), have helped identify new candidate genes associated with the development of bone marrow failure. Targeted NGS using panels of large numbers of genes is rapidly gaining potential for use as a cost-effective diagnostic tool for the identification of mutations in newly diagnosed patients. In this review, we have described recent insights into IBMFS and how they are advancing our understanding of the disease's pathophysiology; we have also discussed the possible implications they will have in clinical practice for Korean patients.

• 대한두개안면성형외과학회지
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• 제16권3호
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• pp.125-130
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• 2015

Background: Poly-L-lactide materials combined with hydroxyapatite (u-HA /PLLA) have been developed to overcome the drawbacks of absorbable materials, such as radiolucency and comparably less implant strength. This study was designed to evaluate the usefulness of u-HA/PLLA material in the repair of orbital medial wall defects. Methods: This study included 10 patients with pure medial wall blow-out fractures. The plain radiographs were taken preoperatively, immediately after, and 2 months after surgery. The computed tomography scans were performed preoperatively and 2 months after surgery. Patients were evaluated for ease of manipulation, implant immobility, rigidity and complications with radiologic studies. Results: None of the patients had postoperative complications, such as infection or enophthalmos. The u-HA/PLLA implants had adequate rigidity, durability, and stable position on follow-up radiographic studies. On average, implants were thawed 3.4 times and required 14 minutes of handling time. Conclusion: The u-HA/PLLA implants are safe and reliable for reconstruction of orbital medial wall in terms of rigidity, immobility, radiopacity, and cost-effectiveness. These thin yet rigid implants can be useful where wide periosteal dissection is difficult due to defect location or size. Since the u-HA/PLLA material is difficult to manipulate, these implants are not suitable for use in complex 3-dimensional defects.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 1991년도 한국자동제어학술회의논문집(국제학술편); KOEX, Seoul; 22-24 Oct. 1991
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• pp.1939-1943
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• 1991

Path planning is an important task for optimal motion of a robot in structured or unstructured environment. The goal of this paper is to plan the shortest collision-free path in 3D, when a robot is navigated to pick up some tools or to repair some parts from various locations. To accomplish the goal of this paper, the Path Coordinator is proposed to have the capabilities of an obstacle avoidance strategy[3] and a traveling salesman problem strategy(TSP)[23]. The obstacle avoidance strategy is to plan the shortest collision-free path between each pair of n locations in 2D or in 3D. The TSP strategy is to compute a minimal system cost of a tour that is defined as a closed path navigating each location exactly once. The TSP strategy can be implemented by the Neural Network. The obstacle avoidance strategy in 2D can be implemented by the VGraph Algorithm. However, the VGraph Algorithm is not useful in 3D, because it can't compute the global optimality in 3D. Thus, the Path Coordinator is proposed to solve this problem, having the capabilities of selecting the optimal edges by the modified Genetic Algorithm[21] and computing the optimal nodes along the optimal edges by the Recursive Compensation Algorithm[5].