• Proceedings of the Korean Institute Of Construction Engineering and Management
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• 2007.11a
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• pp.801-804
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• 2007

Development of construction project management information system is accelerated because information management system has become more important by recent complicated and large-sized construction industry. There are many problems to operate PMIS efficiently because no standardized WBS exist in current. This study has identified the problems of WBS in building construction of multi-family house projects with 4 public and private organizations by interviews and compared each WBS. From those facts, this research presents the integrated WBS and the improved application form in PMIS.

• Proceedings of the Korean Institute Of Construction Engineering and Management
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• 2007.11a
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• pp.151-156
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• 2007

2006년부터 VE 대상프로젝트가 확대되고, 기본설계와 실시설계단계에 각 1회씩 설계VE를 적용토록 규정되어 설계단계별로 VE가 각각 적용되는 프로젝트가 늘어나고 있다. 그리고 원가절감과 성능향상으로 프로젝트 가치를 높인 설계VE 사례도 많아지고 있다. 하지만 기본설계와 실시설계단계의 조건에 적합한 VE 수행방안에 대한 연구가 미진하고 참여자들의 경험과 이해가 부족하여 단계별 설계VE를 효율적으로 수행하는데 많은 어려움이 있다. 본 연구에서는 기본설계단계와 실시설계단계로 나누어 VE를 수행한 실무사례를 분석하여 기능정의와 아이디어 창출간의 연관관계 및 각 설계단계에서 기능정의를 수행할 때 발생하는 문제점을 도출하였다. 문제점을 해결하고 효과적인 설계VE를 수행하기 위하여 다음과 같은 개선방안을 제시하였다. 첫째, 설계프로세스의 흐름에 맞추어 기본설계에는 공간기능에 대하여하고 실시설계에는 부위에 대하여 기능정의를 수행한다. 이때 상위의 레벨에는 하위의 레벨의 기능정의가 연계되는 기능분류체계 (FBS : Function Breakdown Structure)를 제안하였다. 둘째, 기본설계와 실시설계단계의 기능정의를 수행하는 프로세스 (FDP : Function Definition Process)를 제안하였다. 셋째, 실시설계단계에서는 부위별 요구 성능 평가 매트릭스 (EFM : Element Function Matrix)를 적용하여 기능정의와 아이디어 창출이 연계되도록 하였다. 설계VE의 주요 부분인 기능정의 과정에 대한 문제점을 도출하여 해결방안을 제시함으로써, 보다 효과적인 설계VE의 수행을 기대할 수 있다.

• Journal of the Korean Ceramic Society
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• v.49 no.6
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• pp.642-647
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• 2012

$TiO_2$ thin films for a pulse power capacitor were deposited by RF magnetron sputtering. The effects of the deposition gas ratio and thickness on the crystallization and electrical properties of the $TiO_2$ films were investigated. The crystal structure of $TiO_2$ films deposited on Si substrates at room temperature changed to the anatase from the rutile phase with an increase in the oxygen partial pressure. Also, the crystallinity of the $TiO_2$ films was enhanced with an increase in the thickness of the films. However, $TiO_2$ films deposited on a PET substrate showed an amorphous structure, unlike those deposited on a Si substrate. An X-ray photoelectron spectroscopy(XPS) analysis revealed the formation of chemically stable $TiO_2$ films. The dielectric constant of the $TiO_2$ films as a function of the frequency was significantly changed with the thickness of the films. The films showed a dielectric constant of 100~110 at 1 kHz. However, the dissipation factors of the films were relatively high. Films with a thickness of about 1000nm showed a breakdown strength that exceeded 1000 kV/cm.

• Proceedings of the KIEE Conference
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• 1996.11a
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• pp.235-238
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• 1996

An inverted double channel AIGaAs/lnGaAs/GaAs heterostructure grown by LP-MOCVD is demonstrated and discussed. Sheet carrier densities in excess of $4.5{\times}10^{12}cm^{-2}$ at 300K are obtained with a hall mobility of $5010cm^2/V{\cdot}s$. The proposed device with a $1.8{\times}200{\mu}m^2$ gate dimension reveals an extrinsic transconductance as high as 320 mS/mm and a saturation current density as high as 820 mA/mm at 300K. This is the highest current density ever reported for GaAs MODFET's with the same gate length. Significantly improvements on gate voltage swing (up to 3.5 V) and on reverse breakdown voltage (-10V) are demonstrated due to inverted structure.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.62 no.2
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• pp.288-292
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• 2013

This paper presents the result of life-cycle cost (LCC) estimation for domestic products propulsion control system (motor block unit) of KTX-1 considering periodic maintenance. Life cycle costing is one of the most effective approaches for the cost analysis of long-life systems such as the KTX-1. Life cycle costing includes the cost of concept design, development, manufacture, operation, maintenance and disposal. To estimate LCC for domestic products motor block unit, it was analyzed physical breakdown structure (PBS) on motor unit in view of maintenance cost and unit cost etc. As a results, life cycle cost on motor block unit increased moderately expect for periodical time when major parts are replaced at the same time. hereafter this results will be reflected in the domestic products being developed.

• New & Renewable Energy
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• v.8 no.3
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• pp.38-46
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• 2012

Enhanced Geothermal System (EGS) among geothermal system types enables to produce sustainable energy even in non-volcanic region while conventional geothermal energy has been restricted to obtain only from hot and permeable formation such as in volcanic regions. Successful EGS project in terms of economy, however, can be expected only when the project is managed effectively considering most of influencing factors (e.g., tangible and intangible resources, cost, time, risks, etc.). In particular, well construction is of the utmost importance in geothermal project as it dominantly influences on time and cost in the whole project. Therefore, when it comes to viable geothermal project without abundant experience, managing drilling economically and efficiently is inevitable. In this study, a project management system for well construction in geothermal project based on project control system including work breakdown structure and cost account was developed to predict and assess the performance of drilling and to visualize the progress.

• Journal of KIBIM
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• v.13 no.2
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• pp.37-46
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• 2023

The main objective of this study is to propose a method to enhance building safety using the Industry Foundation Classes (IFC) schema in Building Information Modeling (BIM). To achieve this goal, a fire object relationship diagram is created by using the Model View Definition (MVD) and Property Set (Pset) methodology, as well as the Work Breakdown Structure (WBS) based object relationship analysis. The proposed method illustrates how to represent objects and tasks related to fire prevention and human safety during a building fire, including variables that are relevant to these aspects. Furthermore, the proposed method offers the advantage of considering both the IFC object hierarchy and the project work hierarchy when creating new objects, thereby expanding the attribute information for fire safety and maintenance. However, upon confirmation via an IFC viewer after development, a problem with the accuracy of mapping between attributes and objects arises due to the issue of proxy representation of related object information and newly added object information in standard IFC. Therefore, in future research, a mapping method for fire safety objects will be developed to ensure accurate representation, and the scope of utilization of the fire safety object diagram will be expanded. Furthermore, efforts will be made to enhance the accuracy of object and task representation. This research is expected to contribute significantly to the technological development of building safety and fire facility design in the future.

• Proceedings of KOSOMES biannual meeting
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• 2003.05a
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• pp.153-158
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• 2003

Design of general steel structure had applied and achieve elastic design concept mainly so far. Because elastic design supposes that whole structure complies with elasticity formula as that achieve via allowable stress of material is concept that calculate stress distribution of construction about action external load and estimate load of when the maximum stress reaches equally with allowable stress that is established beforehand by maximum safety load of the structure. But, absence that compose actuality structure by deal with external load increase small success surrender and structure hardness falls and tell structure in limit state finally on the whole as showing complicated conduct by interference between these breakdown at buckling by compression. Examined closely about conduct of place since initial buckling through carbon vocal cords transformation finite element analysis series (ANSYS) that place mending condition supposes case that is boundary condition in this investigation.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.46 no.6
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• pp.519-526
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• 2018

In order to analyze space resources, it had to be brought to earth. However, using laser-induced breakdown spectroscopy(LIBS) and Raman spectroscopy, it is possible to analyze qualitative and quantitative analysis of space minerals in real time. LIBS is a spectroscopic method in which a high energy laser is concentrated on a material surface to generate a plasma, and the emitted light is acquired through a spectroscope to analyze the atomic composition. Raman spectroscopy is a spectroscopic method that analyzes the molecular structure by measuring scattered light. These two spectroscopic methods are complementary spectroscopic methods for analyzing the atoms and molecules of unknown minerals and have an advantage as space payloads. In this study, data were analyzed qualitatively by using principal component analysis(PCA). In addition, a mixture of two minerals was prepared and a quantitative analysis was performed to predict the concentration of the material.

• JSTS:Journal of Semiconductor Technology and Science
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• v.3 no.2
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• pp.63-68
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• 2003

The DC and RF characteristics of $In_{0.5}Ga_{0.5}P/In_{0.22}Ga_{0.78}As/GaAs$ p-HEMTs with a gate oxide layer of various thicknesses ($50{\;}{\AA},{\;}300{\;}{\AA}$) were investigated and compared with those of a Schottky-gate p-HEMT without the gate oxide layer. A prominent improvement in the breakdown voltage characteristics were observed for a p-HEMT having a gate oxide layer, which was implemented by using a liquid phase oxidation technique. The on-state breakdown voltage of the p-HEMT having the oxide layer of $50{\;}{\AA}$was ~2.3 times greater than that of a Schottky-gate p-HEMT. However, the p-HEMT having the gate oxide layer of $300{\;}{\AA}$ suffered from a poor gate-control capability due to the drain induced barrier lowering (DIBL) resulting from the thick gate oxide inspite of the lower gate leakage current and the higher on-state breakdown voltage. The results for a primitive p-HEMT having the gate oxide layer without any optimization of the structure and the process indicate the potential of p-HEMT having the gate oxide layer for high-power applications.