• Korean Journal of Construction Engineering and Management
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• v.6 no.6 s.28
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• pp.133-141
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• 2005

In the resent years, the importance of VE (value engineering) and LCC (life cycle cost) analysis for apartment building construction projects has been fully recognized. Accordingly theoretical models, guidelines, and supporting software systems were developed for the value engineering and life cycle cost analysis for construction management including large building systems. However, the level of consensus on VE and LCC analysis results is still low due to the lack of reliable data on maintenance. This paper presents time dependent LCC model based value analysis method for rational investment decision making and design alternative selection for construction of apartment building. The proposed method incorporates a time dependent LCC model and a performance evaluation technique by fuzzy logic theory to properly handle the uncertainties associated with statistics data and to analyze the value of alternatives more rationally. The presented time dependent VE and LCC analysis procedure were applied to a real world project, and this case study is discussed in the paper. The model and the procedure presented in this study can greatly contribute to design value engineering alternative selection, the estimation of the life cycle cost, and the allocation of budget for apartment building construction projects.

• Journal of Applied Reliability
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• v.16 no.3
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• pp.208-215
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• 2016

Purpose: ASRP for the domestic development guided missiles requires not only for the reliability evaluation of the products in storage but also for the life cycle management of the products including development prototypes and initial production items. Methods: For this purpose, it should be performed to build a performance database before and after the accelerated aging test with shelf life items including development prototypes and initial production items, based on which the lifetime prediction should also be carried out. In addition, HILS must be applied for the acceptance test with the initial and follow-up production items, and also for ASRP for the long-term storage products in order to secure systematic quality assurance. Results: The results for the life cycle reliability Improving of domestic development of guided missiles are DB building of prescription Item performance, active application of HILS, Management associated with guided missiles life cycle and to Secure technology data about the introduction of foreign guided missiles. Conclusion: Furthermore, it is demanded that DTaQ, the managing agency of ASRP, actively take part in the process to maintain reliability engagement consistency over the life cycle of guided missiles.

• Computers and Concrete
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• v.25 no.2
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• pp.167-179
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• 2020

Optimal design of structures against earthquake loads is often limited to reduce initial construction costs, while the cost induced to structures during their useful life may be several times greater than the initial costs. Therefore, it is necessary to consider the indirect costs due to earthquakes in the design process. In this research, an integrated methodology for calculating life cycle cost (LCC) of moment-resisting concrete frames is presented. Increasing seismic safety of structures and reducing human casualties can play an important role in determining the optimal design. Costs incurred for structures are added to the costs of construction, including the costs of reconstruction, financial losses due to the time spent on reconstruction, interruption in building functionality, the value of people's life or disability, and content loss are a major part of the future costs. In this research, fifty years of useful life of structures from the beginning of the construction is considered as the life cycle. These costs should be considered as factors of calculating indirect costs of a structure. The results of this work represent the life cycle cost of a 4 story, 7 story, and 10 story moment-resisting concrete frame by details. This methodology is developed based on the economic conditions of Iran in 2016 and for the case of Tehran city.

• KIEAE Journal
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• v.12 no.1
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• pp.105-112
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• 2012

When a building is planned and designed, the design should be able to minimize the cost during the whole life cycle of the building. This study has begun to analyze LCC about the alternative design which is applicable to renewable energy facility construction. It is reviewed domestic and foreign papers about the trend of LCC technology and it is determined the analytical method to analyze the LCC of renewable energy. Regarding the review of alternatives, it is chosen the three alternatives which are able to designed combing the renewable energy facilities and it is performed the LCC analysis about each alternative. Alternative 1 is Photovoltaic + Solar Thermal + Photovoltaic /Wind Power, Alternative 2 is Geothermal + Photovoltaic, and Alternative 3 is Photovoltaic + Solar Thermal. The LCC analysis is present value method, its analytical period is 40 years and it is applied 3.2% of real discount rate. As a result, it is proved that Alternative 1 and Alternative 3 are not able to collectible the early investment cost during the analytical period and Alternative 2 is analyzed that its pay-back period of early investment cost is about 31 years. As the final outcome of this study on case analysis, it is more advantageous to use the combination of Geothermal and Photovoltaic energy than to use the other combination in LCC aspect.

• Journal of the Korean Recycled Construction Resources Institute
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• v.6 no.1
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• pp.8-15
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• 2018

Waste concrete accounts for the largest portion of construction waste, and the supply of natural aggregate is unstable. Therefore, importance of using recycled aggregate is emphasized. The purpose of this study is to investigate the mechanical properties of high strength concrete according to the replacement rate of recycled coarse aggregate. For this purpose, the target design compressive strength was set to 40MPa, and the substitution rates of the recycled coarse aggregate were set to 0%, 30%, 60%, and 100%, respectively. Through experiments on the unreinforced concrete and hardened concrete, The validity of the use was confirmed. In addition, LCA method was used to evaluate the environmental impact of recycled aggregates and to compare and analyze the environmental impacts of the aggregates.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.22 no.12
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• pp.859-866
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• 2010

This study examined the economics of a solar water heating system for an office building using life cycle cost (LCC) optimization simulations. The numerical simulations were conducted with TRNSYS and GenOpt employing the Hooke-Jeeves algorithm. The solar collector area, slope, mass flow rate per collector area and storage tank volume were selected as the main design parameters of the solar water heating system. The LCC optimization simulations of the system were carried out for cases where water temperature was $60^{\circ}C$ and $50^{\circ}C$. The results showed that for water temperature at $60^{\circ}C$ and $50^{\circ}C$ the collector area could be decreased by 17% and 28%, storage tank volume could be decreased by 49% and 54%, and mass flow rate per collector area increased by 5% and 9% respectively compared to a non-optimized system. The LCC of the system was reduced by 4% for $60^{\circ}C$ and 7% for $50^{\circ}C$. The initial installation cost of the system was reduced by 24% for $60^{\circ}C$ and 34% for $50^{\circ}C$. However, the operating cost of the system increased by 16% for $60^{\circ}C$ and 36% for $50^{\circ}C$ compared to a traditional solar water heating system.

• Journal of the Korean Recycled Construction Resources Institute
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• v.7 no.2
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• pp.123-130
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• 2019

The purpose of this study is to confirm the strength characteristics of concrete according to the mixing ratio of recycled fine aggregates and to use it as basic data for the use of recycled fine aggregates in concrete. For this purpose, the target design compression strength was set at 27MPa. Considering practical use of recycled aggregate, the mixing ratio of recycled fine aggregate was set at 0, 30, 60, and 100%, and the unconfined concrete and hardened concrete were tested. The LCA method was used to evaluate the environmental impact of recycled fine aggregate concrete, and the effectiveness of recycled fine aggregate in the production of concrete was verified.

• Korean Journal of Construction Engineering and Management
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• v.15 no.3
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• pp.58-65
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• 2014

This study aims to understand the environmental impact reduction of green buildings that are certified by Green standard for energy and environmental design(G-SEED). To ensure this end, this study assessed and compared the environmental impacts(global warning, ozone layer depletion, acidification, and eutrophication) of a G-SEED-certified elementary school building(green building) and an uncertified elementary school building(traditional building) using the life cycle assessment methodology. This study considered the environmental impacts from the material manufacturing, material transportation, on-site construction, and operation during 40 years. The comparison of the environmental impact intensity of two buildings showed that the green building generated much more environmental impacts than the traditional building. For example, the global warming potential of the green building was approximately 12.5% higher than of the traditional building since the global warming potential of the green building was 3.751 $t-CO_2eq./m^2$ while that of the traditional building was 3.282 $t-CO_2eq./m^2$. It signifies that the G-SEED doesn't guarantee the reduction of the environmental impacts in terms of four impact categories. Therefore, the G-SEED should be complemented and improved to achieve the environmental impact reduction.

• Journal of Korean Elementary Science Education
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• v.33 no.2
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• pp.306-321
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• 2014

This study aims to analyze difficulties that pre-service elementary teachers experience in investigating the life cycle of a common cabbage butterfly in person. As difficulties they face during the process of this research, they pointed out collecting eggs, observing molting, creating environments for a breeding cage, feeding, building a breeding cage, and making butterfly specimens. Out of all the environmental difficulties related to their school fields, they pointed out a difficulty of time management most of all, followed by placing a breeding cage in the classroom and the lack of microscopes for observation. In regard to difficulties related to their evaluations on students' activities, they found it difficult to evaluate students' activity with the life cycle of an insect in the aspect of knowledge and even to set evaluation criteria. Besides, many of them responded that it would be appropriate to evaluate a research on the life cycle of an insect through a portfolio or an observation journal. In regard to difficulties in terms of teachers' knowledge, they found it difficult to understand insect molting, metamorphoses, complete metamorphoses, incomplete metamorphoses, the structure of an insect body, and how to distinguish a female insect from a male one. In regard to the application of class models, they knew it is important for students to have various experiences through direct observation, so the experience-based learning model was proper for the process of observing the life cycle of a common cabbage butterfly. However, they found it difficult for students to observe each stage of the life cycle in person.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2012.05a
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• pp.53-54
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• 2012

This study is aimed at utilizing LCA processor with BIM LOD, eliciting the problems of the existing environmental assessment by constructing the database for environmental values of green buildings. For these objects, environmental load database of BIM construction material and evaluation process are presented, after matching BIM family based environmental load database which is available during evaluation stage, input-output tables and Korea LCI database to standard item code of public procurement service. It is a important factor in environmental assessment of building to develop database unit of standard item code for BIM and construction material. Thus, the results of this study are expected to provide basic data for improving effectiveness of construction through BIM based environmental load evaluation database. Furthermore, the provided environmental load database unit for construction material is considered to be available as basic information for BIM study by suggesting a processor connecting BIM with LCA and along with this, continuous examination on the connection process is needed.