• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2014년도 춘계 학술논문 발표대회
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• pp.162-163
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• 2014

Operation and maintenance stage consists the largest portion of project life cycle cost. Appropriate management and analysis of such stages have massive effect on the total project cost. The effective prediction of optimized repair period is one of main factors in ㅌ management. However, it has been analyzed that the prediction of appropriate repair period revealed limitations in reliability. Therefore, this study suggests a methodology of repair period prediction by dividing finished projects into similar groups with same properties to be compared with the target project using quantitative variables.

• 자원ㆍ환경경제연구
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• 제20권3호
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• pp.459-487
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• 2011

포스트 교토체제에서는 A/R CDM 등 산림 분야의 중요성이 증대할 것으로 전망된다. A/R CDM에 대한 정확한 경제성 평가는 투자의사결정에 유용한 정보를 제공하여 투자 활성화로 이어질 수 있다. 본 연구에서는 전통적 경제성 평가 방법이 간과한 의사결정자의 의사결정권의 가치 내지 기다림의 가치를 반영한 실물옵션 방법에 의해 모형을 구축하고 실제 A/R CDM 사례를 적용하여 실증분석을 하였다. 그 결과 적용 사례의 경우 최적투자분기점이 추정된 l-CER의 가격보다 낮게 나타남으로써 적절한 투자의사결정이 이루어졌음을 알 수 있었다. 그러나 할인율의 수준과 적용 범위에 따라 최적투자분기점과 투자의사결정이 크게 영향을 받는 것으로 나타났다.

• 한국표면공학회지
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• 제39권5호
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• pp.235-239
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• 2006

The aluminum nitride(AlN) layer on Al7075 substrate has been formed through nitrogen ion implantation process. The implantation process was performed under the conditions : 100 keV energy, total ion dose up to $2{\times}10^{18}\;ions/cm^2$. XRD analysis showed that aluminum nitride layers were formed by nitrogen implantation. The formation of Aluminum nitride enhanced surface hardness up to 265HK(0.02 N) from 150HK(0.02 N) for the unimplanted specimen. Micro-Knoop hardness test showed that wear resistance was improved about 2 times for nitrogen implanted specimens above $5\;{\times}\;10^{17}\;ions/cm^2$. The friction coefficient was measured by Ball-on-disc type wear tester and was decreased to 1/3 with increasing total nitrogen ion dose up to $1\;{\times}\;10^{18}ions/cm^2$. The enhancement of mechanical properties was observed to be closely associated with AlN formation. AES analysis showed that the maximum concentration of nitrogen increased as ion dose increased until $5\;{\times}\;10^{17}\;ions/cm^2$.

• Transactions on Electrical and Electronic Materials
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• 제9권5호
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• pp.206-208
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• 2008

Implantation of metals and ceramics with ions of nitrogen and other species has improved surface properties such as friction, wear and corrosion in numerous industrial applications. In recent years, PCB drills tend to be more minimized increasingly as the electronics components have been more highly accumulated and minimized. Therefore nitrogen ion implantation was performed onto PCB drill (0.15 & 0.3 mm in diameter), in order to investigate mechanical properties of WC-Co cermets surface through Nano-indentation tests. PCB drill was implanted at energy of 70 keV, 90 keV, 120 keV and with the dose range of $1{\times}10^{17}$ and $5{\times}10^{17}\;ions/cm^{2}$. After ion implantation, WC-Co PCB drill bits was tested in actual operating situation to apply cutting tools industry and is concluded that the life time of nitrogen ion implanted PCB drills is one and a half times longer than the unimplanted.

• 한국정보통신학회:학술대회논문집
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• 한국해양정보통신학회 2004년도 SMICS 2004 International Symposium on Maritime and Communication Sciences
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• pp.80-84
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• 2004

The goal of the project is to study and describe a new stressed state of High Temperature Superconducting (High-Tc) YBCO Films, to create of SQUIDs on the bases of these Films with maximal sensitivity. The problems of the project are: 1. The experimental studying of the stressed films growing by laser ablation method. 2. The studying of stressed film properties. 3. The making of the dc-SQUIDs with maximal sensitivity on the bases of the stressed YBCO films.

• Advances in aircraft and spacecraft science
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• 제2권1호
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• pp.1-16
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• 2015

In this paper, geometrical and mechanical approaches are proposed for the simulation of the draping of woven fabric onto complex parts. The geometrical discrete approach allows to define the ply shapes and fibres orientation in order to optimize the composite structural properties and the continuum meso-structural mechanical approach allows to take into account the mechanical properties of fibres and resin and the various dominating mode of deformation of woven fabrics during the forming process. Some numerical simulations of forming process are proposed and compared with the experimental results in order to demonstrate the efficiency of our approaches.

• 한국주거학회논문집
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• 제16권3호
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• pp.101-107
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• 2005

The reason that compulsory removals of a low-quality housing redevelopment such as involuntary or unintentional migration present a problem for urban communities is that whether involuntary movers adapt themselves to their new home has an influence on the urban communities that surround them. Moreover, involuntary emigrants have higher probability of choosing faulty residential areas than voluntary emigrants do. This gives rise to a problem of another residential migration for involuntary movers. In order to solve these problems, there is a need for a new housing policy that enables original residents to come back to their old community. However studies for resettlement had not conducted subjects about housing redevelopment characteristics which influences the involuntary movers directly. Instead personal microscopic characteristics such as statistics of resettlement, the moving distance, the reason of moving, improvement of living environment, had been main subjects of farmer studies. So the purpose of this study is to analyze an analysis of the relationship between resettlement and housing redevelopment characteristics. The data used in this study was obtained at 47 areas designated by Seoul (metropolis) since 1990 for redevelopment. Cluster Analysis Is used for dividing high rate of resettlement with low rate of resettlement and Regression Analysis is used for the analysis of the relationship between resettlement and housing redevelopment characteristics. The results of examining the effects of a redeveloped housing complex on returning residents at 47 areas designated by Seoul (metropolis) since 1990 fur redevelopment are as follows: First, A housing complex with a high returning rate (remove-in rate?) has no state/public land, unauthorized building owners who are in the low-income brackets, and few interested parties such as union members. This is the characteristic of a redeveloped housing complex with a short-period project span. On the contrary, a housing complex that has a low returning rate is crowded by state/public land, and numerous unauthorized building owners, and interested parties. Second, According to the linear regression analysis, among the factors that affect returning residents, 'physical properties(characteristics) of a region', 'population properties within a region', and 'properties of a project span' indicate a negative(-)influence whereas 'properties of a complex density' shows a positive(+) influence. In a nutshell, the more the physical properties, population properties, projectspan properties, the lower the returning rate and the more the complex density properties, the higher the returning rate. In detail, an area with many small land and new/large buildings, a high population, and a long project duration has a low returning rate of original residents while an area holding large capacity and buildings with many number of floors (multiple-storied building) has a high returning rate.

• 식품과학과 산업
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• 제49권2호
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• pp.78-82
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• 2016

DB Integration website(tentatively named Food Processing Aptitude Information Center, FPAIC) has been designed through a "high-value products development project(2013)". Basically, the project aims to secure connections between food raw materials and processing industry, a variety of information sources, and users's convenience. It also aims to build the industry-university-based mutual growth in the food industry through sharing of processing suitability and material research on food raw materials. FPAIC consists of raw material story, information of sample characteristics, food processing study, preceding research data, food industry trends, and understanding of food processing. The major database of research on Food Processing is provided on information of sample characteristics, and food processing study. Currently the web site has 36 raw material stories, 380 information on sample characteristics and food processing studies, 1,600 preceding research data about 31 food raw materials. The web site also provides information on 70 useful web sites, as well as 77 food industry trends, 27 basic information about food processing.

• KIEAE Journal
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• 제9권6호
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• pp.3-11
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• 2009

Building materials have a great impact on the health of a building's occupants. Thus, it is imperative that their health-related properties be taken into during the course of construction project. Unfortunately, no current database system exists that can provide information on the health performance of building materials at each stage of construction project management, from planning and design to building and maintenance. therefore, an inordinate amount of time and effort is required to choose the right health-friendly materials(DBHM). To solve this problem, this study aims at building a database management system for health-friendly building materials. It analyzes the health-related properties and performance of various materials, and proposes a database structure and operation algorithm. The system proposed in this study is expected to contribute to the objective evaluation of health-friendly building materials through the accumulation of relevant data.

• 국제학술발표논문집
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• The 6th International Conference on Construction Engineering and Project Management
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• pp.213-216
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• 2015

Despite the significant increase of Korean contractors in the international construction market, many SMCCs (Small & Medium Construction Companies) have suffered in the global financial crisis, and some of them have been kicked out of the international market after experiencing huge losses on projects. SMCCs face obstacles in the international market, such as an insufficient ability to gather information and inappropriate management of associated risks, which lead to difficulties in establishing effective business strategies. In other words, making immature decisions without an effective business strategy may cause not only the failure of one project but also the bankruptcy of the SMCC. To overcome this, the research presented herein aims to propose a decision support system for SMCCs, which would screen projects and make a go/no-go decision at the early stages of international projects. The proposed system comprises a double axis: (1) a profit prediction model, which evaluates 10 project properties using an objective methodology based on a historical project performance database and roughly suggests expected profit rate, and (2) a feasibility assessment model, which evaluates 17 project environment factors in a subjective and quantitative methodology based on experience and supervision. Finally, a web-based system is established to enhance the practical usability, which is expected to be a good reference for inexperienced SMCCs to make proper decisions and establish effective business strategies.