• Korean Journal of Construction Engineering and Management
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• v.10 no.2
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• pp.102-110
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• 2009

The cost for maintenance of bridge structures such as repair or reinforcement is increasing. In addition, the efforts for inspection of bridge structures is becoming more important since the proper repair or reinforcement should be performed to save the maintenance cost and ensure the safety for public infrastructure. Therefore, it is studied on this paper to estimate the repair or reinforcement cycles using probabilistic approach for the steel-box girders of bridge superstructure. In addition, a computer simulation program is uniquely developed based on probabilistic approach to calculate the cycles derived from the function of age of bridge and performance rating curve which were previously studied. In order to ensure the reliability of results and appropriateness of the model, statistical analyses were performed. Also, the results were compared and proved to be similar with ones from previous statistical data related to the repair or reinforcement cycles. The results from this study is expected to be useful for the determination of proper time to repair or reinforce the bridge structure and raise the safetyness of bridge structure in advance.

• International conference on construction engineering and project management
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• 2011.02a
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• pp.597-602
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• 2011

A robust asset management methodology is essential for effective decision-making of maintenance, repair and rehabilitation of a bridge network. It can be achieved by a computer-based bridge management system (BMS). Successful BMS development requires a reliable bridge deterioration model, which is the most crucial component in a BMS, and an optimal management philosophy. The maintenance optimization methodology proposed in this paper is developed for a small bridge network with limited structural condition rating records. . The methodology is organized in three major components: (1) bridge health index (BHI); (2) maintenance and budget optimization; and (3) reliable Artificial Intelligence (AI) based bridge deterioration model. The outcomes of the paper will help to identify BMS implementation problems and to provide appropriate solutions for managing small bridge networks.

• Journal of Information Technology Services
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• v.20 no.1
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• pp.81-92
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• 2021

As the degree of economic development of society increases, the maintenance issues on the existing social overhead capital becomes essential. Accordingly, the adaptation of the concept of Level of service in highway maintenance is indispensable. It is also crucial to manage and perform the service level such as road assets to provide universal services to users. In this regards, the purpose of this study is to improve the maintenance service rating model and to focus on the assessment items and weights among the improvements. Particularly, in determining weights, an Analytic Hierarchy Process (AHP) is performed based on the survey response results. After then, this study conducts unsupervised neural network models such as Self-Organizing Map (SOM) and Davies-Bouldin (DB) Index to divide proper sub-groups and determine priorities. This paper identifies similar cases by grouping the results of the responses based on the similarity of the survey responses. This can effectively support decision making in general situations where many evaluation factors need to be considered at once, resulting in reasonable policy decisions. It is the process of using advanced technology to find optimized management methods for maintenance.

• Journal of the Korean Society for Aviation and Aeronautics
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• v.25 no.3
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• pp.123-134
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• 2017

In order to advance into the MRO industry, the Aviation maintenance organization with suitable for the standards for personnel, facilities and operations should be first approved by FAA and EASA. The purpose of study is designed to arrange the standards required for personnel, facility, operation rule for approval of Repair Station maintenance organizations certified by FAA PART 145 of the US Federal Aviation Regulation. Also to consider the following differences through the comparative analysis with domestic AMO certification of the information in the Management, Maintenance Process, and Quality System for approval of maintenance organization authorized, the additional EASA PART 145. As a comparative analysis on maintenance organization certification in the country between FAA and EASA, this study could show us that domestic maintenance organization, certified manual contents are used by applying just many of the FAA system. And we could know that as part of the EASA maintenance organization certification process, airmen personnel were relatively systematically segmented and controlled. For domestic maintenance organization certification, operational as policy implications we would like to present policy implications such as the implication of rating system of Aviation Mechanic License like EASA, the financial support of the training center to resolve the shortage of the FAA or EASA license holders, operational organization as "CAMO" for systematic aviation mechanic certified system should be required, continued construction of hangar or MRO for airworthiness repair under Governmental support, and varied application of DER system from FAA accordingly.

• Korean Journal of Biological Psychiatry
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• v.8 no.1
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• pp.140-146
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• 2001

In clinical setting, treatment-refractoriness, medication induced tardive dyskinesia and amenorrhea in chronic schizophrenia are frequently problematic. However, there are few guideline solving these problem available to clinicians. The goal of this study was collecting clinical data on clinical effectiveness and predictors of response of switching to olanzapine. We attempted to switch to olanzapine from risperidone and clozapine in chronic 31(risperidone 17, clozapine 14) schizophrenia and schizoaffective disorder patients suffering from sustained symptoms, weekly blood monitoring, medication induced tardive dyskinesia and amenorrhea. Previous antipsychotics dosage was gradually decreased for 2 or 3weeks, at the same time olanzapine dosage was gradually increased. At baseline, after 1 week, after 2 weeks and after 4 weeks we checked Brief Psychiatric Rating Scale, Clinical Global Impression Scale, Sympson-Angus Rating Scale, Barnes Akathisia Rating Scale and followed up after 12 months. Successful switch after 4 weeks was achieved in 25 patients(clozapine 9(64.2%), risperidone 16(94.1%)). Overall, mean BPRS and CGI scores increased significantly. Successful maintenance after 12 months was achieved in 17 patients(clozapine 5(35.7%), risperidone 12(70.5%)). Overall, mean BPRS and CGI scores increased significantly too. Switching to olanzapine from other atypical antipsychotics is recommendable in chronic schizophrenia with treatment refractoriness and drug induced side effect.

• Journal of Korean Society on Water Environment
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• v.23 no.3
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• pp.385-390
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• 2007

Reliable flow measurement for dry season is very important to set up the in-stream flow exactly and total maximum daily load control program in the basin. Especially, in the points which tidal current effects are dominant because reliability of the low measurement decrease. The reliable measuring methods are needed. In this study, we analysis the water surface elevation difference of water surface elevation. Quantity relationship to consider tidal currents in these regions. It is known that tidal current effects from Nakdong river barrage are dominant in Samrangjin measuring station. We developed multiple regression equation with water surface elevation, quantity, and difference of water surface elevation and compared these results water measured rating curve. All of these regression equation including linear regression equation and log regression equation fits better measured data them existing water surface elevation quantity line and Among three equations, the log regression equation is best to represent the measured the rating curve in Samrangjin point. The log regression equation is useful method to obtain the quantity in the regions which tidal currents are dominant.

• KIEAE Journal
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• v.13 no.6
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• pp.67-75
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• 2013

The present duration of 5 years in the Korea Green Building Certification(G-SEED) should be re-set taking into account with the needs for renewal of re-certification criteria. This study methods is to analyze the differences between the characteristics of the certification system of green building of domestic and foreign and to seek the improvement to derive the problem of detailed evaluation items of the examination. The purpose of this study is to identify some problems of re-certification criteria in the G-SEED System and to propose the renewal of certification system. Analysis of the rating criteria with a few re-certified examples of office buildings have been made. Some measures to improve the re-certification have been suggested as follows; (1) it is strongly suggested to establish re-certification rating systems that is not yet made, (2) the new criteria of re-certification bring into focus on whether buildings maintain the environmental performances of the initial status certified, and (3) thus the effective duration of re-certification needs to re-set flexibly in a way to confirm to the initial environmental performances and maintenance conditions certified.

• Fire Science and Engineering
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• v.20 no.4 s.64
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• pp.98-104
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• 2006

The Fire Protection Regulatory documents require the fire-resistive rating of fire barrier penetration seals be same as that of fire barriers. Pilot application of penetration seal evaluation for K nuclear plant, built before penetration seal requirements were made, was done. In this evaluation, visual inspection and estimating fire rating by comparing installed configuration with tested configuration of penetration seals, called bounding approach method, were applied. Further improvements for retrofit and maintenance are recommended with penetration seal evaluation results also. The practical use of the methodology adopted in this study and the evaluation result of K nuclear plant will be anticipated for other plant's penetration seal evaluation.

• Proceedings of the Korea Water Resources Association Conference
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• 2006.05a
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• pp.746-751
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• 2006

The geumjunggu of the onchunchun which is the upper stream have been maintained as a too much picture to become a concrete lining about existing low flow channel and the reservoir water protecting banks for the reason of the flow of an upper stream steep slope and back of the shortage of the channel area in a suitableness interval. This research made a rating-curve to decide since to ensure against risks to the flood control through the undo of the rivers. And we found the speed of current of a nature undo interval and existing concrete interval and water level change out. A result from this natural disposition we must apply as a data for the research about the plan to be established in the rivers maintenance basis plan of onchunchun.

• Nuclear Engineering and Technology
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• v.40 no.4
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• pp.251-254
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• 2008

Issues and themes concerned with nuclear power plant uprating are examined. Attention is brought to the fact that many candidate nuclear power plants for uprating have anyway been operated below their rated power for a significant part of their operating life. The key issues remain safety and reliability in operation at all times, irrespective of the nuclear power plant's chronological or design age or power rating. The effects of power uprates are discussed in terms of material aspects and expected demands on the systems, structures and components. The impact on operation and maintenance methods is indicated in terms of changes to the ageing surveillance programmes. Attention is brought to the necessity checking or revising operator actions after power up-rating has been implemented.