• Korean Journal of Construction Engineering and Management
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• v.20 no.4
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• pp.3-12
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• 2019

VE analysis is a method to secure definite functions and performance by defining user's various requirements clearly and propose alternatives to reduce cost. However, the present domestic VE project has difficulty in defining design function analysis clearly due to time constraints as well as difficulty in effective and efficient communication between project stakeholder. Domestic results of VE were largely focused on reducing cost while maintaining the functions of the existing facility. Therefore, this study aims to secure the optimal functions for users according to the original intent of user requirements through QFD-VE model which project VE participants can make collective and cooperative decision making. QFD-VE is a technique that first, it can make collaborative decision making in defining and modifying of design function and setting the importance of requirement function. Second, it allow project VE participants to check design interference and conflict between neighbor systems. This study also provided a mathematical model for implementing the computer system using QFD-VE in the future.

• Proceedings of the Korea Water Resources Association Conference
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• 2021.06a
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• pp.451-451
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• 2021

인간활동으로 인해 서식처의 변화, 서식처의 파편화를 비롯하여 기후변화, 토지이용의 변화 등으로 생태계 생물 다양성은 빠르게 손실되고있는 상황이다. 특히 생물 다양성은 생태계 복원력에 중요한 인자로서 유역의 건전성 회복을 위해 생물 다양성을 중요한 인자로 고려하려는 경향이 커지고 있다. 유역 건전성은 주로 큰 하천에서의 친수성, 서식처, 유량 및 수질 등에 적용되어왔고 국내에서는 최근 들어 유역 건전성을 확보하기 위해 수량 및 수질관리, 환경문제 등의 해결을 위해 유역관리 차원에서 접근하려는 시도가 시작되었으나 어떠한 수단을 통해 생물다양성과 서식처 관리를 접근할 수 있는지에 대한 연구는 아직 부족한 실정이다. 이에 본 연구에서는 최근 20년 동안 도시화, 댐 건설 등 토지이용변화가 크게 발생한 금강유역(9,865 km²)을 대상으로 InVest 모델 중 서식처 가치평가 모델 (Habitat Quality Model)을 이용하여 유역의 서식처 가치를 평가하고 이를 수생태계 건강성 모니터링 자료와 비교하여 모형의 적용성을 평가하고자 한다.

• Journal of Korean Society of Environmental Engineers
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• v.31 no.8
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• pp.611-618
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• 2009

Road construction has been worked on by focusing on cost effectiveness such as the reduction of construction costs without understanding the natural environment and ecosystems. In addition, since ecosystems have been destroyed and the habitats of animals and plants have been isolated, wild animals have sought other habitats or have moved into isolated habitats. Thus, issues such as roadkills or the extermination of species are increasingly occurring. Based on this background, the development and application of a general assessment method need to be researched in order to verify whether or not spaces or habitats where animals can be inhabited and their species can be maintained exist. The purpose of this study is to develop an ecosystem map where a conservation value evaluation method considering the functions of an ecosystem where animals live as well as the naturalness of ecosystems is used and can be made into a drawing. The items applied to evaluate the habitat conservation values were naturalness, rarity, and functionality, and sub-items for evaluation were created. GIS as well as the evaluation items were used to create a digital map about the level of importance based on the evaluation criteria. The created digital map showed that it was not limited to the adjustment or distribution of the fauna and flora but was applicable for a general ecosystem evaluation method for the conservation of habitats. It is expected that the isolation of habitats would be able to be minimized if the digital map is used for road construction projects. The digital map is deemed to be able to be used for the construction of environmentally friendly roads, which will minimize the destruction of ecosystems and the isolation of habitats for creatures.

• Korean Journal of Construction Engineering and Management
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• v.12 no.2
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• pp.89-100
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• 2011

As an impactive factor on industries and national economy, The Social Overhead Capital(SOC) is major factor to determine the national competitiveness and the investment of SOC is essential for its economic growth. Accordingly, introduction of the preliminary feasibility study and establishment of legal institutionalization and evaluation system has been carried out and reviewed since 1999. Nevertheless of these efforts, basic problems such as lack of scientific method for investment evaluation and loss of effectiveness on feasibility studies are continuously being brought up. Moreover, as the preliminary study to improve the mentioned problems is mainly focused on the economic and estimated demand analysis, the study of policy analysis, the most important phase during a feasibility study, is still insufficient. Therefore, in this paper, a quantitative decision-making model, to which the performance assessment method of Value Engineering(VE) is applied, is developed and proposed to improve the policy analysis of (preliminary) feasibility study that requires combining with relative studies, to induce quantitative analysis method, and to contribute the improvement of value on the political aspect for SOC investment goals and use as a strategic decision-making method by systematic analysis.

• Korean Journal of Construction Engineering and Management
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• v.24 no.6
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• pp.45-52
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• 2023

Recently, as climate change caused by greenhouse gases is intensifying, the international community has committed to reduce greenhouse gas emissions. The purpose of this study is to present the methodology and major considerations for investment judgment. Two actual cases of overseas projects were selected as study subjects. As an analysis method, the major risk factors were defined as a probability distribution, and the NPV was stochastically estimated using the Monte Carlo simulation method. In addition, assuming a policy change, the range of NPV change was analyzed. As a result, the average NPV of project A was lowered by 19%, and the probability of showing a negative NPV was 12.2%. The average value of project B was lowered by 12.5%. Considering the policy change, project A can obtain economic benefits only when it obtains 72.9% or more of the total amount of carbon credits generated, and project B is economically feasible when it acquires 49.5% or more. As a result, the average value of project A is lower than the net present value under basic assumptions, so caution is needed in investment decisions depending on changes in major risk factors. Additionally, considering policy changes, the carbon credit distribution ratio should be differentially applied depending on the project size, and this was presented as a specific figure.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.28 no.6D
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• pp.871-879
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• 2008

Recently, as there are a rise in the standard of living and higher concerns of an electromagnetic wave and environment, undergrounding the aerial cables which are supported by large pylons and generally considered as the least attractive feature of an urban area is on an increasing trend to improve aesthetic benefits and electric reliability. This study applied Contingent Valuation Method (CVM) which is expected to become an effective tool to measure indirect benefit to estimate the substantial benefits of undergrounding overhead power line projects in an urban area. The tunneling construction project of the 345kV Shinsungnam electric power cable in Seongnam city was selected and a hypothetical scenario was given to respondents to determine their levels of Willingness to Pay (WTP) for undergrounding overhead power lines. The result from the estimation of the WTP of undergrounding overhead power lines in Seongnam city was calculated as approximately 17.1 billion won. Placing existing overhead lines underground is difficult to justify economically. Most undergrounding costs appear to be justified by aesthetic and public policy considerations. Therefore, considering the result of this study, undergrounding overhead power lines is of great benefit to public.

• Proceedings of the Safety Management and Science Conference
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• 2002.11a
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• pp.17-23
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• 2002

Value can be defined as function divided by cost. The ultimate goal of VE (Value Engineering) is to simultaneously reduce cost and to enhance function in given projects. In general, there are eight phases (Selection, Investigation, Speculation, Evaluation, Development. Presentation, Implementation, and Audit) to perform VE. This paper presents analysis of important factors for VE in construction fields using QFD (Quality Function Deployment) technique. QFD was introduced in 1972 to help design supertanker in Mitsubish's shipyards in Kob, Japan and formally defined by the American Supplier Institute in 1987 as a system for translating consumer requirements into appropriate company requirements at every stage, from research, through product design and development, to manufacture, distribution, installation, and marketing, sales and services. The objective of this paper is to provide and analyze the trend on the viewpoint of efficient value engineering of field workers. The data are collected by questionnaires. The samples for this study are chosen from 13 companies in Korea during 2 months (2002. 7 ∼ 2002. 8). The results of this study will play an important role not only for the efficient value engineering but also for preparing of life cycle cost analysis.

• Korean Journal of Construction Engineering and Management
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• v.8 no.6
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• pp.197-206
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• 2007

The age of synthetic correspondence against "development period shortening, high quality" is about to come. While the product is becoming complexation gradually and also diversification, life cycle of product gets shorted. Under the infinity competition age, the certain answer of "the survival of the fittest" is that the enterprise itself must be able to shorten development and delivery term, reduce product development and life cycle cost, and satisfy customer in performance and value. From this point of view, concurrent engineering's theory, which develops the process of product in the manner of repetition, parallel, and synchronousness, is realized as a important strategy instrument in construction. This study investigates and analyzes several examples in order to apply concurrent engineering successfully, and presents the decision-making model through the simulation about the factor affecting in each process.

• Korean Journal of Construction Engineering and Management
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• v.12 no.4
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• pp.50-58
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• 2011

Lean concept is management philosophy that defines a customer's value and eliminates wasteful and impeditive factors. Management philosophy of Lean in the construction industry is referred to as "Lean Construction". Now this concept has expanded to achieve effective productivity during the design phase. Currently the norm of the domestic design process has been Point-based Design(PBD). It involves selecting a single structurally-feasible design option early and then refining that single design as more information becomes available throughout the design process. This single design is then re-worked until a solution is found that is feasible for all parties. On the contrary, Set-based Design(SBD) is based on lean processes to eliminate waste and improve project productivity. It focuses on keeping the design space as open as long as possible, to allow "subdesign" to advance and not labeling them as secondary in importance. Preserving the maximum number of feasible designs as long as possible reduces the likelihood that rework will be necessary and allows all project participants to utilize their unique expertise to make the project successful. This study proposes that the design methodology of minimizing waste and increasing productivity through SBD of AHP, one of the decision making process so as to compare PBD with SBD and tries to find decision making process and then suggest that application methodology through performs case study of SBD process.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.17 no.4
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• pp.280-293
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• 2005

In this study, a model to calculate the expected total construction cost has been developed by combining a model to calculate the sliding distance of a caisson of a vertical breakwater and a model to calculate the rehabilitation cost of a caisson. The optimal cross-section of a caisson of a vertical breakwater is defined as the cross-section that requires a minimum expected total construction cost within the allowable limit of caisson sliding. Two allowable limits are considered: 0.1 m of the expected sliding distance during the lifetime of the breakwater and 0.1 of the probability that the cumulative sliding distance during the lifetime of the breakwater is greater than 0.3 m. A discount rate has also been introduced to convert the future rehabilitation cost to the present value. The introduction of the discount rate reduces the expected total construction cost for the caissons designed for shorter return periods due to frequent rehabilitations. The present design method requires a smaller cross-section than the conventional deterministic method in shallow water depths, enabling us to design a caisson more economically. On the other hand, the above-mentioned allowable limits of caisson sliding show similar results for smaller water depths, while, for larger depths, the former requires a larger cross-section than the latter.