• Korean Journal of Construction Engineering and Management
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• v.20 no.6
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• pp.44-56
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• 2019

Recently, the paradigm of SOC investment has shifted from new construction to maintenance. This shift became more important for the highway system because it is as one of the most important SOC. In Korea, highway maintenance costs are about 20% of the total annual highway construction budget, which is about two-thirds of developed countries. In addition, establishing standardized guidelines for the highway maintenance operation is not in place. Therefore, in order for domestic road construction and maintenance technology to secure competitiveness in the global construction market, it is urgent to improve the management capacity for maintenance as well as the technology and management capacity. This study examines highway maintenance practices in OECD countries such as North America, Europe, Australia, New Zealand, and Japan to identify core elements of highway maintenance practice. It is imperative to establish a comprehensive management system based upon asset management principle. Even if the budget for the highway construction is reduced, investment in maintenance needs to be maintained.

• Journal of the Korean Society of Food Culture
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• v.24 no.3
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• pp.344-349
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• 2009

The principal objective of this study was to assess the effects of various ratios of sesame oil to shortening on the characteristics and stability of lipids in Yackwa. The sesame oil to shortening ratios assessed herein were 100:0, 75:25, 50:50, and 1:100. The lipid contents of Yackwa prepared with various shortening ratios ranged from 25.20 to 29.12%. The lipids in these Yackwa consisted primarily of the frying oil (soybean oil), and the oil contents were measured between 84-90%. The fatty acid compositions of the lipids in the Yackwa were unrelated to the ratio of shortening. The fatty acid compositions were as follows: linoleic acid 49.1-51.27%, oleic acid 26.05-26.77%, palmitic acid 10.07-11.71%, linolenic acid 5.51-5.72% and stearic acid 4.51-4.68%. These compositions were similar to that of soybean oil, which was the frying oil used to prepare the Yackwa. The acid value, peroxide value, and carbonyl value of the lipids in Yackwa did not differ with the various shortening ratios used during the storage time. Stability of lipids in Yackwa were mainly effected by frying oil. Our results suggest that shortening should prove useful as a substitute for sesame oil in the preparation of Yackwa.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.14 no.1
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• pp.59-68
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• 1996

This study suggests that the management of bridge was developed data which supports to execute analysis a-bout bridge. Basically, it makes standardization that the item of management of bridge keeps the effective data management which demonstrates the designed database by graphic processing technic and development of pro-gram in database manipulation. As a result of this study, through the analysis of the management of bridge, we tried to make the acceptable management item standard and to design database. For the purpose of it, computer program and database design with analyzing current works, stable inspection processing demanding the management of bridge and taking adventage of them. In this study, we can get the minimuim cost of the management of bridge and keep maximum common usage. also we contribute to perform effective data management and management system of bridge.

• Journal of Korean Society of Steel Construction
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• v.20 no.2
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• pp.259-268
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• 2008

This paper proposes a method to establish an optical lifetime maintenance strategy for deteriorating bridges in consideration of life-cycle performance and cost. A program is developed based on the proposed method, which can generate optimum maintenance scenarios not only at the individual member level but also at the system level of the bridge. By applying the developed program is studied through the comparative analysis of maintenance strategies generated at each level. According to the results of comparison between maintenance strategies of the member-level analysis and system-level analysis. It is expected that the establishment of a maintenance strategy through the bridge system-level analysis considering target, members reflects practical and reasonable results.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.35 no.3
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• pp.737-745
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• 2015

The purpose of this study is to clarify the challenges and suggest regulatory improvement strategy by investigating the Japanese building maintenance system which had been conducted for decades. The efficiency and problems of the current building maintenance system of Korea are analyzed by stake holders and purpose of management. The results show that several strategies are important to improve the quality of building maintenance. They include check list focusing on the purpose of maintenance, efficient and fair criteria, rational checking period considering owner's budget, cooperation with professionals in facilities, and promotion of professional companies participation. The results imply that the challenges should be solved systematically rather than individually.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.20 no.4
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• pp.367-374
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• 2002

Maintainability of highways is an important problem that is considered in the planning steps of a highway development process. A number of asset management systems have been developed to precisely predict maintenance and pavement expenditures for better decision making, But these systems are not helpful in reducing maintenance costs. Optimization of some highway design characteristics in the planning phases may reduce maintenance costs over the life cycle of highway. The formulations for initial and maintenance costs have been developed based on which design variables can be chosen to minimize these costs, focusing on the sideslope in cut and fill sections. Maintenance cost has been represented as a function of sideslope, width of highway cross section, and annual average daily traffic. A real geographic database of between Chung joo and Sang joo city in Choong buk was used and it is presented to investigate the sensitivities of maintenance cost and soil characteristics in selecting alignments. In this study, we present that maintenance cost and soil characteristics are important considerations in alignment optimization.

• The Journal of Korean Academy of Prosthodontics
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• v.55 no.1
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• pp.71-78
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• 2017

The retaining methods of implant prosthesis were classified into a screw-retained and a cement-retained type. A screw-retained prosthesis has many advantages, such as retrievability, preventing residual cement, while their disadvantages include the possibility of screw loosening and fracture, on the contrary advantages of cement-retained prosthesis are relatively low cost, but they are difficult to retrieve. To combine the advantages of both type, screw-cement retained prosthesis (SCRP) type have been introduced. But they still require ideal implant placement. So we introduce fiber post retained prosthesis without residual cement for preventing soft tissue trouble due to excessive cement.

• Proceedings of the Korean Association of Geographic Inforamtion Studies Conference
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• 2004.03a
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• pp.407-413
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• 2004

GIS는 '단번에' 효과가 나타나는 다른 전산시스템과는 달리 최소한 3～4년의 손익분기점을 가지는 기술인 만큼 효과적인 운영이 중요하고, 효과적인 운영을 위해서는 자료의 최신성을 확보할 수 있는 DB의 지속적인 유지관리 활동이 그 무엇보다도 중요하다고 할 수 있다. 그러나 지자체를 중심으로 구축되어 있는 대부분의 GIS 활용체계는 준공과 동시에 운영과 유지관리 차원에서 적절한 대처를 수행하지 못함으로 인해 손익분기점 달성에 대한 회의적인 시각을 갖는 것이 지배적이라 할 수 있다. 특히 지자체 GIS사업이 추진되는 과정에서 각 시스템에 맞는 실질적인 유지관리 방안을 모색하고 이에 대한 충분한 교육이 진행되어야 함에도 불구하고 실제는 그렇지 못한데 그 원인이 있을 것이다. 그러나 보다 근원적인 문제점은 실제 유지관리 활동을 위해 무엇을 어떻게 해야 하는지에 대한 구체적인 방안을 가지고 있지 못한 것이 더욱 크다고 하겠다. 실제로 모든 사업추진과정에서 정해진 방법론에 의해 유지관리방안을 마련하게 되어 있으나 아주 형식적인 수준에서의 언급이 대부분이고 지자체라는 행정기관의 특성과 지자체 GIS의 주된 대상이 공사 및 시설물 관리와 관련되어 있다는 업무적 특성은 전혀 배제되고 있는 것이다. 그렇다면 실제로 GIS DB의 유지관리가 원활하게 진행되기 위해서는 어떻게 해야만 하는 것일까\ulcorner 이 질문에 대한 접근을 위해 본 연구에서는 GIS DB의 갱신이 일어나는 발생원인을 정확하게 진단하고 발생원인의 특성과 행정기관의 특성을 적절히 연계시켜 유지관리 모델을 제시하는데 그 목적이 있다. 이를 위해 ‘선 유지관리 후 활용체계 정비의 중요성’을 점검하고, ‘변동자료 발생원인의 분석’, ‘명확한 변동자료 입력 근거의 확보’, ‘갱신주체별 역할의 정의 및 유지관리 기준의 설정’, ‘분야별업무 특성을 고려한 관련 기준의 마련 및 타 시스템과 연계되는 항목을 고려한 절차 정의’ 등에 대한 다양한 접근을 시도하였다. 본 연구에서 제시하는 유지관리 모델을 기반으로 각 지자체별로 적절한 컨설팅이 진행되고 이에 따라 담당자의 실천이 이루어진다면 지자체 GIS의 투자대비 효과에 대한 기대는 이상이 아닌 현실로 다가오게 될 것이다.가오게 될 것이다.

• Proceedings of the Korean Institute Of Construction Engineering and Management
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• 2007.11a
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• pp.167-174
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• 2007

This study proposes a practical and realistic method to establish an optimal lifetime maintenance strategy for deteriorating bridges by considering the life-cycle performance as well as the life-cycle cost. The proposed method offers a set of optimal tradeoff maintenance scenarios among other conflicting objectives, such as minimizing cost and maximizing performance. A genetic algorithm is used to generate a set of maintenance scenarios that is a multi-objective combinatorial optimization problem related to the and the life-cycle cost and performance as separate objective functions. A computer program, which generates optimal maintenance scenarios, was developed based on the proposed method. The subordinate relation between bridge members has been considered to decide optimal maintenance sequence. The developed program has been used to present a procedure for finding an optimal maintenance scenario for steel-girder bridges on the Korean National Road. Through this bridge maintenance scenario analysis, it is expected that the developed method and program can be effectively used to allow bridge managers an optimal maintenance strategy satisfying various constraints and requirements.

• The KIPS Transactions:PartD
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• v.16D no.3
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• pp.353-360
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• 2009

Most information systems are component-based and developed by outsourcing, and developed software is maintained integrative. However, studies on cost measurement indicators and cost estimation model have not been performed sufficiently, which are foundational to enhance the productivity and efficiency of maintenance. This study suggests indicators to measure maintenance cost for component-based software and examines maintenance cost estimation model of component software by the measurement indicators suggested. In order to generate the indicators to measure the component-based maintenance cost, the previously proposed indicators are summarized comparatively. To estimate the measurement indicators of component-based software, it makes a comparison of the previously proposed indicators and arranges them. We classify the measurement indicators by how to apply according to maintenance types of component software and then we propose the cost measurement indicators. Moreover, we propose the cost estimation model according to the maintenance types of component software using the suggested measurement indicators suggested. With the suggested estimation model, a case study is performed and its validity is verified.