• 한국군사과학기술학회지
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• 제12권2호
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• pp.236-247
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• 2009

In Korea, the driving system restriction criteria is strictly applied(gross weight 400kN, axial load 100kN). Especially after the Seoungsu Bridge accident, safety factor has been strictly applied. The Safety factor is applied to the cumulative results for each steps like design, construction, maintenance of the Bridge. Because of it, the bridge is undervalued compared to its capacity. So, this generates loss for both private and military sector(eg. logistical delays, structural damage, etc.). But analyzing data from many existing researches we have confirmed that the military heavy vehicle may pass through the first class bridges. In consequence, this study have focused on determining whether HETS vehicles can pass over the first class bridge, without safety issues, using MIDAS structural analysis program. The results have confirmed that the military heavy vehicle may pass over the bridge.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 1999년도 하계종합학술대회 논문집
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• pp.741-744
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• 1999

In this paper, We represent a low complexity of parallel canonical basis multiplier for GF( q$^{n}$ ), ( q＞ 2). The Mastrovito multiplier is investigated and applied to multiplication in GF(q$^{n}$ ), GF(q$^{n}$ ) is different with GF(2$^{n}$ ), when MVL is applied to finite field. If q is larger than 2, inverse should be considered. Optimized irreducible polynomial can reduce number of operation. In this paper we describe a method for choosing optimized irreducible polynomial and modularizing recursive polynomial operation. A optimized irreducible polynomial is provided which perform modulo reduction with low complexity. As a result, multiplier for fields GF(q$^{n}$ ) with low gate counts. and low delays are constructed. The architectures are highly modular and thus well suited for VLSI implementation.

• Corrosion Science and Technology
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• 제4권1호
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• pp.29-32
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• 2005

A various structural materials are used in construction projects such as a stone, concrete, steel materials. Between of them, concrete are used widely. The compressive strength of concrete is high, and its maintenance and management is comparatively easy. The R.C Building will be superannuated as time passes. This program is generated by propagation of cracks. In order to manage such cracks, time and efforts, expense, etc. are required. In this study, glass sensors were embedding in a model beam and column and leakage of fluorescence and adhesive material was investigated. Further, currents in glass pipe were observed to find the leakage of liquid in glass pipes. Progressive cracks generated by cause the fracture of glass pipes. Therefore, the liquid become to flow and electric current stops, and the cracked part of the member can be found easily. Moreover, the adhesive delays progressive cracking system that responds in air, and the life of a structure can be made to extend. The purpose of this research is to develop of low price sensors that can perform of self-diagnosis in addition to ability of concrete repair concrete to damage.

• 대한안전경영과학회지
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• 제13권1호
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• pp.31-39
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• 2011

In this study, supervision resides fire mission against problems associated with case studies and surveys done through the side of the field work, technical personnel, fire management, including fire code aspects classified into three kinds of items dealt with the issue. Started at the scene of the problem in terms of performance, the issue of the construction process, mainly dealt with the issue at the time of completion. Fire management side, supervisor of technical personnel, human resources management issues, contract issues, fire code level, the frequent revisions of fire regulations, supervision, processing delays of the resulting report, the problem resides with the expansion of Fire Supervision target was mentioned. Finally, the target for each hierarchical supervision, and resident supervisor of the need for supervision of work performance test was carried out by the correlation.

• 한국항공운항학회지
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• 제6권1호
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• pp.125-145
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• 1998

The term "Privatization" has a different meaning in different contexts and cultures. In this paper, the term "Privatization" in the context of airports is defined as the movement of an entity from the government sector to the private sector. This is the definition that is commonly employed in the U.S. Airport revenue can he divided into two sub-categories of aeronautical revenue and non-aeronautical revenue. At many of the major international airports, however, non-aeronautical revenue has been growing faster than the aeronautical revenue, contributing an increasingly larger share of the total revenue. And the best way to enhance simultaneously the airport operations. With the remarkable growth in the air traffic volume of pssengers and cargo. more and more mega-international airports have been built or are under construction. As the air transport demand is expected to increase at an even greater rate in the 21st century, new types of airports which will be free of current major problems. such as airport congestion and flight delays are badly needed.

• 한국건설관리학회논문집
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• 제15권2호
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• pp.12-22
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• 2014

건설현장에서 발생하는 소음으로 인하여 많은 사람들이 고통을 겪고 있고, 그로 인하여 민원과 분쟁이 증가하고 있다. 이러한 민원은 사업의 지연 및 중단, 배상액 지불과 같은 시간적, 경제적 손실을 초래하므로 엄격하게 관리되어야 한다. 이와 같은 추세에 따라 정부는 기존 방음벽 중심의 소음정책에서 탈피하여 발생원 중심으로 소음을 관리하기 위해 노력하고 있다. 그러나 건설소음은 일시적이고, 불규칙적으로 발생하며, 건설장비 자체의 소음레벨이 높기 때문에 쉽게 제어되기 어렵다. 또한 최근 선진국을 중심으로 사람들에게 쉽게 인지되지는 않지만, 고주파 소음과 마찬가지로 인체에 정신적, 신체적 피해를 주는 저주파 소음에 대한 연구를 활발히 진행하고 있다. 그러나 기존의 수동적인 소음관리방식으로는 고주파 소음을 저감하는데 효과가 있을 뿐, 저주파 소음을 저감하는데는 한계가 있다. 그러므로 본 연구는 건설현장에서 발생하는 소음을 저감하고, 기존의 수동적인 소음관리방식의 한계점을 보완하기 위한 방법으로 능동소음제어를 이용하여 건설현장에서 발생하는 소음을 저감하기 위한 관리모델을 제안하는 것을 목적으로 한다. 이를 위하여 시뮬레이션 실험을 수행하였고, 능동소음제어의 건설현장 적용성을 검토하였다. 본 논문은 능동소음제어를 통하여 건설현장에서 발생하는 소음을 저감하고, 소음피해로 인한 민원과 분쟁을 최소화하는데 일조할 수 있을 것이라 기대한다.

• Journal of Construction Engineering and Project Management
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• 제5권1호
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• pp.11-19
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• 2015

This paper presents optimized artificial neural networks (ANNs) claims prediction and decision awareness framework that guides owner organizations in their pre-bid construction project decisions to minimize claims. The framework is composed of two genetic optimization ANNs models: a Claims Impact Prediction Model (CIPM), and a Decision Awareness Model (DAM). The CIPM is composed of three separate ANNs that predict the cost and time impacts of the possible claims that may arise in a project. The models also predict the expected types of relationship between the owner and the contractor based on their behavioral and technical decisions during the bidding phase of the project. The framework is implemented using actual data from international projects in the Middle East and Egypt (projects owned by either public or private local organizations who hired international prime contractors to deliver the projects). Literature review, interviews with pertinent experts in the Middle East, and lessons learned from several international construction projects in Egypt determined the input decision variables of the CIPM. The ANNs training, which has been implemented in a spreadsheet environment, was optimized using genetic algorithm (GA). Different weights were assigned as variables to the different layers of each ANN and the total square error was used as the objective function to be minimized. Data was collected from thirty-two international construction projects in order to train and test the ANNs of the CIPM, which predicted cost overruns, schedule delays, and relationships between contracting parties. A genetic optimization backward analysis technique was then applied to develop the Decision Awareness Model (DAM). The DAM combined the three artificial neural networks of the CIPM to assist project owners in setting optimum values for their behavioral and technical decision variables. It implements an intelligent user-friendly input interface which helps project owners in visualizing the impact of their decisions on the project's total cost, original duration, and expected owner-contractor relationship. The framework presents a unique and transparent hybrid genetic algorithm-ANNs training and testing method. It has been implemented in a spreadsheet environment using MS Excel$^{(R)}$ and EVOLVERTM V.5.5. It provides projects' owners of a decision-support tool that raises their awareness regarding their pre-bid decisions for a construction project.

• 대한토목학회논문집
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• 제32권6D호
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• pp.615-622
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• 2012

숏크리트는 현장에서 빠른 시공을 실시하여 굴착면을 침식으로부터 보호하고 암괴의 전단이동방지, 암괴의 붕괴방지, 개구절리의 봉합, 응력의 집중완화, 응력전달효과 등에 의하여 후속작업의 원활한 진행이 될 수 있도록 굴착면을 방지하여 지내력을 증대시키는 것이 주목적이다. 숏크리트공법으로는 건식과 습식의 두 가지방법이 있으며, 1997년 이후부터는 건식보다 습식 숏크리트가 많이 이용되고 있다. 그러나 작업 중 목적물에 부착되지 않고 반발되는 현상, 즉 리바운드가 많이 발생하며 이러한 많은 양의 리바운드는 숏크리트와 전체 공사비 원가에 중대한 영향을 미치게 된다. 특히 숏크리트는 재료비, 배합, 타설시간 증가, 재료의 취급과 계량장치에 소요되는 인력 및 버력제거를 위한 비용 증가 발생원인이 되고 있다. 이 연구에서는 국내현장에서 시행한 급결제 함유량에 따른 일반 습식 숏크리트 및 강섬유 습식 숏크리트공법의 시공실적을 분석하여 반발 양 및 강도의 실험적인 분석을 실시하였다. 또한 국내 건설공사에 실제 사용할 수 있는 효과적이고 합리적인 방법을 제시하였다.

• 무역상무연구
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• 제47권
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• pp.129-156
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• 2010

Since the 1970s, international construction employers have commonly requested first demand guarantees upon their contractors as a form of security for due performance of their works. Contractors prefer the greater protection offered by more traditional forms of security requiring presentation of an arbitral award or other evidence of the caller's entitlement to compensation. Many contractors nonetheless feel that they have no alternative but to provide these unconditional guarantees in order to compete. However, these unconditional first demand guarantees are controversial and have given rise to numerous disputes both in arbitration and litigation. Disputes arising from first demand guarantees can be broken down into a) applications to prevent a perceived fraudulent or otherwise unfair or improper calling of a guarantee, b) claims arising from such abusive calls and c) claims relating to the consequences of such calls even if the call itself may not be abusive as such. The contractors should carefully assess the risk of an abusive call being made bearing in mind the difficulties he may face in seeking to prevent such a call. He should also bear in mind the difficulties, delays and cost he is likely to encounter in seeking to recover any monies wrongfully called. One option would be to provide that the call can only be made once and to the extent that the employer's damages have been assessed or even incurred or even for the default to have been established by an arbitral tribunal or court. Another option would be to provide that any call be accompanied by a decision of a competent and impartial third party stating that the contractor is in breach. For example, such a requirement could be incorporated into a construction contract based on the FIDIC Conditions by submitting this decision to a Dispute Adjudication Board. Another option would be to provide for the "ICC Counter-Guarantee Scheme". In sum, there would appear to be room for compromise between the employer and the contractor in respect of first demand guarantees by conditioning the entitlement to call such guarantees to the determination of a competent and impartial third party.

• 한국건설관리학회논문집
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• 제1권1호
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• pp.45-52
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• 2000

국내의 SOC 사업은 그 기획단계에서 업무 추진의 근거가 될 수 있는 업무 절차와 의사결정의 기준 등이 미비하거나 표준화되지 못한 상태에서 추진되고 있으며, 이로 인하여 사업수행 과정에서 여러 가지 시행착오를 겪고 있는 것이 현실이다. 따라서 SOC사업의 기획업무 과정에서 모든 사업목표와 관리대상에 대한통합관리의 기능을 수행할 수 있는 정형화된 절차 모델의 개발이 필요하며, 본 연구는 SOC사업의 기획업무 개선을 위한 기획관리 모델 개발의 기반을 구축하는데 그 목적을 두었다 모델 개발의 적용범위는 도로, 철도, 공항, 항만을 포함하는 교통시설로 한정하였고 주요 연구결과로서, 현행 SOC 사업의 문제점 제시와 함께 기획단계의 업무 프로세스, 각 단계별 중점 고려사항, 기획업무 개선을 위한 핵심적 개선방향을 SOC사업 기획관리 모델 개발의 기반으로 제시하였다.