• Proceedings of the Korean Institute Of Construction Engineering and Management
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• autumn
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• pp.329-332
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• 2003

The Ministry of Construction and Transportation has estimated the reconsideration of economy in construction and the dullness of LCC forcast method which supports decision-marking in safety and maintenance of buildings. So, they have introduced LCC analysis method in steps of a feasibility study and design. Because of the introduction of LCC analysis process and method, it would be possible to make a logical decision from management maintenance, estimation, user point of view. In this study, it would bepossible to show a plan and alternative of design factors and structure in one building by using LCC analysis method and to compare and analyze the reduction of life circle cost bi the elapsed time.

• Journal of the Korean Society for Precision Engineering
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• v.21 no.9
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• pp.85-94
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• 2004

As over 70% of the total life cycle cost (LCC) of a product is committed at the early design stage, designers are in an important position to substantially reduce the LCC of the products they design by giving due to life cycle implications of their design decisions. During early design stages, there may be competing concepts with dramatic differences. In addition, the detailed information is scarce and decisions must be made quickly. Thus, both the overhead in developing parametric LCC models fur a wide range of concepts, and the lack of detailed information make the application of traditional LCC models impractical. A different approach is needed, because a traditional LCC method is to be incorporated in the very early design stages. This paper explores an approximate method for providing the preliminary LCC, Learning algorithms trained to use the known characteristics of existing products might allow the LCC of new products to be approximated quickly during the conceptual design phase without the overhead of defining new LCC models. Artificial neural networks are trained to generalize product attributes and LCC data from pre-existing LCC studies. Then the product designers query the trained artificial model with new high-level product attribute data to quickly obtain an LCC for a new product concept. Foundations fur the learning LCC approach are established, and then an application is provided.

• Journal of the Korean Society of Industry Convergence
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• v.24 no.4_1
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• pp.377-385
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• 2021

High voltage direct current(HVDC) systems has been an alternative method of a power transmission to replace high voltage alternate current(HVAC), which is a traditional AC transmission method. Due to technical limitations, Line commutate converter HVDC(LCC-HVDC) was mainly used. However, result from many structural problems of LCC-HVDC, the voltage source converter HVDC(VSC-HVDC) are studied and applied recently. In this paper, after analyzing the reactive power and output voltage ripple, which are the main problems of LCC-HVDC, the characteristics of each HVDC are summarized. Based on this result, a new LCC-HVDC structure is proposed by combining LCC-HVDC with the MMC structure, which is a representative VSC-HVDC topology. The proposed structure generates lower reactive power than the conventional method, and greatly reduces the 12th harmonic, a major component of output voltage ripple. In addition, it can be easily applied to the already installed LCC-HVDC. When the proposed method is applied, the control of the reactive power compensator becomes unnecessary, and there is an advantage that the cut-off frequency of the output DC filter can be designed smaller. The validity of the proposed LCC-HVDC is verified through simulation and experiments.

• Korean Journal of Construction Engineering and Management
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• v.9 no.6
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• pp.216-224
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• 2008

Recently, most developed countries use the evaluation system about Life Cycle Cost(LCC), and KOREA is beginning to introduce the system to reduce construction expenses. And the introduction of "Technical Proposal Type Bid", which is a new procurement method of Korea government, has made needs for the price-valuation way to evaluate facilities LCC. These days, LCC has been being evaluated by BTL and turnkey project in KOREA, which is suffering from difficulties in evaluating it, because evaluation elements and standards are vague. In addition, LCC evaluation in public construction business except BTL and turnkey is not carried out. Therefore, this paper is to develop a new evaluation index to evaluate LCC both systematically and objectively. The results of this paper are as followings. (1) Necessity and problem analysis of LCC evaluation index, (2) LCC evaluation index deduction from the technical report and question analysis, (3) Application and evaluation method suggestion to practice.

• Journal of the Korean Electrochemical Society
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• v.8 no.4
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• pp.162-167
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• 2005

Using Pechini method, we synthesized the $La_{0.6}Ca_{0.41}CrO_3$ (LCC41) and $La_{0.8}Sr_{0.05}Ca_{0.15}CrO_3$ (LSCC) powders for slurry dip coating, and $La_{0.75}Ca_{0.27}CrO_3$ (LCC27) powder for air plasma spray coating. The sintering property of the powders and their coating properties were investigated. The average particle sizes of the LCC41, LSCC, LCC27 were 0.6, 0.9, $1.5{\mu}m$, respectively. The relative density of LCC41 bulk was to be found about 98%. The LSCC coating on anode support prevented Ca migration of the coated LCC41 on the anode some or less, which was confirmed from EDS result. The air plasma spray-coated LCC27 with the dip-coated LCC41 were more dense and showed better electrical conductivity than those of the air plasma spray-coated LCC27 and the dip-coated LSCC and LSCC41. The LCC41 and LCC27 showed good electrical conductivities, but the LSCC had a poor electrical conductivity probably due to low sinterability

• Korean Journal of Construction Engineering and Management
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• v.8 no.5
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• pp.71-79
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• 2007

It is common that the analysis of VE/LCC is performed in design phase of quay wall structures. The analysis is mainly executed based on experience and engineering sense of expert considering the selection of construction method, construction and maintenance cost. Recently there are increasing demands on the analysis that includes uncertainty and vulnerability of input parameters, for this purpose, fuzzy reliability based probabilistic VE/LCC analysis model for quay wall structures is suggested. In VE/LCC analysis for quay wall structures, the application of probabilistic analysis method give very similar results compare with those of deterministic analysis method. It is anticipated that the methodology proposed in this paper can also be utilized in the design and maintenance phase of other facilities where decision making is made for the probabilistic life cycle cost and value analysis.

• Proceedings of the KSR Conference
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• 2007.11a
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• pp.1050-1057
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• 2007

The objective is to compare with economic evaluation and to analysis the LCC for prestressed concrete used on rail bridge. A new style concrete bridge is difficult to estimate a history for maintenance cost reliably. For the reason, we introduce a analogical interpretation by similar bridge style in order to estimate a appropriate maintenance profile. The proposed method is usefully supplied to estimating the LCC for bridge which is difficult to determine the maintenance cost.

• Journal of the Korea Institute of Building Construction
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• v.8 no.5
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• pp.127-134
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• 2008

The purpose of this study is to propose the decision making technique in roof waterproofing method at the early construction stage. Selecting the suitable construction method is difficult because of the complex interrelationships between many factors of influencing the construction method selection. This study presents an example of selecting suitable method by analyzing LCC (Life Cycle Cost) in roof waterproofing work. In this study, roof waterproofing method is analyzed by LCC(Life Cycle Cost) which is consists of the initial costs, running costs, and removal costs. Sheet waterproofing, membrane waterproofing and asphalt waterproofing costs are compared to select the most economic method. The result of this study revealed that considering LCC is useful in selecting the proper method in the construction work.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 2004.10a
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• pp.339-346
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• 2004

This paper presents a method to minimize Life-Cycle Cost(LCC) of steel box girders. The LCC function considered in this paper includes initial cost, expected life-cycle maintenance cost and repair cost. A resistance force curve is derived from a condition grade curve of steel girders and optimal design of steel box girders is performed on the basis of derived resistance force curve. Also, in this paper annual costs of various case in LCC are compared and analyzed. It is concluded that the optimal design of steel box girders considering LCC by a presented method will lead to more economical and safer girders than conventional design.

• Journal of the Korean Society of Safety
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• v.24 no.2
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• pp.62-68
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• 2009

Life Cycle Cost(LCC) is adopted to decide the target of safety level in designing suspension bridges. The LCC are evaluated considering two types of uncertainty; aleatory and epistemic. The nine alternative designs of suspension bridge are simulated to decide the safety level which can minimize the LCC. The LCC is calculated through the probability of failure and safety index including the uncertainty. This method results in the useful tool deciding the optimum safety level with minimal LCC as the main design factor.