• Proceedings of the KIEE Conference
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• 2005.07b
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• pp.1038-1040
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• 2005

This paper describes the optimal design, construction and performance evaluation of voltage divider used in high power testing laboratory for voltage measuring system. These dividers, which are of R, C, R&C type voltage dividers, the voltage to be measured range from voltage to several ten kilovolts, the frequency of the signals has a bandwidth from DC to megaHertz Measuring transient voltage and currents in the high voltage power laboratory is generally accompanied by electromagnetic interface and induced noise. above all, the measuring capabilities of voltage measuring system are dependent upon short response time and it must be as free as possible of inductive effects. In this paper presents both characteristic of voltage divider and design of voltage measuring system.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2005.10a
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• pp.432-435
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• 2005

The Mega-pixel camera phones become main trends in mobile phone market. The lens modules used in mesa-pixel camera phones need high resolution. One of the main factors of resolution drop is the defects of bare lens. Though there are many advantages in auto-inspection of defects of bare lens, high technical problems take the defect inspections to be done with manual process. In this paper, the type and the source of defects were described and bare lens defect auto-inspection system design was explained. The designed auto-inspection system is composed of illumination optics part, focusing optics part and auto-moving system. With the proposed auto-inspection system, fast and uniform inspection of bare lens can be achieved.

• Korean Journal of Construction Engineering and Management
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• v.9 no.3
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• pp.75-84
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• 2008

Recently, construction industry demands have been changed by domestic construction circumstances such as high-technology, mega-projects, and the complexity of construction. In order to deal with the change of such a domestic construction circumstances, the Ministry of Construction and Transportation (MOCT) has introduced advanced delivery methods. However, the advantages and disadvantages of the advanced delivery methods have not been effectively applied for previous projects. The reason for this is that the "Reviewing Standard for the Large-scale Construction Bidding Method" has not reflected enough prcject characteristics when the delivery method is selected in the project planning phase. Therefore, this paper proposes the Analysis on the Impact Factors of Delivery Method for Multi-Family Housing Projects.

• Proceedings of the Korea Water Resources Association Conference
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• 2015.05a
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• pp.210-210
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• 2015

전 세계적으로 기후변화로 인한 자연재난은 피해의 규모에 따라 대형화 다양화 집중화 현상이 일어나고 있으며, 이로 인한 사회 경제적 피해가 과거에 비해 지속적으로 증가하고 있다. 한국에서는 이러한 자연재난 중 피해의 90%이상이 수해 풍해 설해 등으로 조사되었으며, 특히, 수해에 의한 피해가 자연재난으로 발생하는 피해 중 가장 큰 비중을 차지하고 있다. 최근에는 2014년 일본의 태풍 '판폰'과 '봉퐁', 2013년 중국의 태풍 '피토'와 '다나스', 2012년 한국의 태풍 '볼라벤', '덴빈', '산바' 등 연속적인 호우사상의 내습으로 인한 피해가 발생함에 따라 동시 다발적인 거대 호우사상의 발생에 대한 대비책이 시급한 실정이다. 국내 외적으로 단일 호우사상으로 인한 홍수 피해 대책에 관한 연구는 활발하게 이루어지고 있지만, 동시다발적 연속적인 호우사상으로 인한 홍수 피해 대책 연구는 미비한 실정이다. 이에 따라 본 연구에서는 단기간에 거대 호우사상이 동시 다발적 연속적으로 나타나는 현상을 거대홍수라고 정의하고, 거대홍수에 대응하기 위해서 거대홍수 발생에 따른 홍수범람 및 홍수피해액을 산정하였다. 홍수범람모의를 통해 거대홍수가 유역전체에 미치는 영향을 파악하고, 다차원홍수피해산정법(MD-FDA)을 통해 홍수 피해액을 산정하여 거대홍수방어 대책 수립의 참고 자료로써 활용할 수 있을 것이다.

• Proceedings of the Korea Water Resources Association Conference
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• 2016.05a
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• pp.153-153
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• 2016

최근 지구온난화 및 기후변화의 영향으로 수재해가 증가하고 있으며, 강우의 경향성이 변화하고 있다. 태풍 및 집중호우로 인한 피해보다 장기간의 연속적인 강우의 발생으로 인한 피해가 더욱 크며, 기존 수공구조물의 설계기준은 연속적인 호우로 인한 피해를 고려하지 못하고 있는 실정이다. 거대홍수란 집중호우, 태풍, 이상홍수 및 돌발홍수로 인한 홍수피해의 여파가 끝나기도 전에 또 다른 강우사상으로 인하여 거대한 홍수가 발생하는 시나리오적 상황을 의미한다. 본 연구에서는 기상청에서 제공하는 한강권역 30년 동안의 (1986 ${\infty}$ 2015년) 강우자료를 이용하여 거대홍수 발생횟수, 경향성, 설계기준을 초과하여 발생하는 거대홍수 초과빈도를 분석하였다. 최소 무강우 시간 정의(Inter Event Time Definition, IETD)를 이용하여 거대홍수를 산정하고, Mann-Kendall test 및 이중누가우량분석(double mass analysis)을 통하여 거대홍수의 경향성 분석을 실시하였다. 본 연구의 결과는 기존 수공구조물의 설계기준의 취약점을 보완할 수 있을 것이라 판단되며, 태풍, 집중호우, 거대홍수 등으로 발생하는 홍수피해를 줄이기 위한 방재 사업의 우선순위 결정에 대한 근거 자료로 활용할 수 있을 것이라 기대된다.

• Journal of the Korean Solar Energy Society
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• v.33 no.3
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• pp.114-123
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• 2013

In these days, most of the office buildings are being required to save energy for maintenance. lighting system constitutes 20% to 30% of the total annual electrical energy consumption in office buildings. As an energy saving strategy for lighting system, dimming control system based on illuminance sensors came into use. But the system is accompanied with many illuminance sensors to control lighting and needs a lot of initial investment. In this study, the prediction equation for indoor daylighting illuminance distribution is proposed through the review for conventional research results and field measurements. The proposed equation was verified by the comparison between predicted results and field measurement results. The developed prediction equation for daylighting can be used to control the indoor illuminance level with the limited sensor when dimming control system is operated.

• Plant Journal
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• v.7 no.4
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• pp.77-87
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• 2011

In proportion to continuing growth of overseas plant market and the trend of its mega scale of the project, the importance of management is significantly emphasized for the successful execution of the project. And it is recognized that progress control is the most important management item amongst the others in the management. Progress control is importance of progress measurement for performance measurement and process control of project, but it is hardly obtainable securing the objectivity in the progress measurement since the progress measurement are being applied differently in accordance with the project conditions and the experience level of the person in charge for the progress control. This study has conducted as following to propose a standard method for progress measurement in a petrochemical plant protect. Domestic and overseas plant projects are investigated variously with the applied method of progress measurement, and the deduced problem of progress measurement. And then standard method for progress measurement of engineering, procurement, construction and commissioning has been proposed according to comparison and analysis of practices in domestic & overseas plant project, procedures for progress control in the globally reputed petrochemical client, company rules and recommendation of the expert in progress control.

• Journal of Navigation and Port Research
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• v.45 no.2
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• pp.54-60
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• 2021

The aim of this study is to determine the critical factors and construction requirements for a new deep-water seaport system in the Lach Huyen area in northern Vietnam. In this study, the Analytic Hierarchical Process (AHP ) method was used to evaluate the importance of the criteria and subcriteria. The results were as follows: the principal criterion "geographical location (0.151)" ranked as the most important criterion for building a new deep-water port system, which is affected by the subcriteria "direct sea route with mega-vessel" and "good liner connectivity index". The principal criterion "port competency (0.145)" ranked second; thus, it can be concluded that good competitiveness of a port' will provide many benefits to the port and the region. Regarding the implication, the established evaluation framework can be used for port construction to make a more reasonable judgment. In a future study, the scope of evaluation factors should be widened, involving participation of broader stakeholders, such as shipping companies, forwarders, and logistics companies.

• Advances in robotics research
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• v.2 no.3
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• pp.183-199
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• 2018

This paper presents the development of a 3D printed humanoid robotic hands of SignBot, which can perform Malaysian Sign Language (MSL). The study is considered as the first attempt to ease the means of communication between the general community and the hearing-impaired individuals in Malaysia. The signed motions performed by the developed robot in this work can be done by two hands. The designed system, unlike previously conducted work, includes a speech recognition system that can feasibly integrate with the controlling platform of the robot. Furthermore, the design of the system takes into account the grammar of the MSL which differs from that of Malay spoken language. This reduces the redundancy and makes the design more efficient and effective. The robot hands are built with detailed finger joints. Micro servo motors, controlled by Arduino Mega, are also loaded to actuate the relevant joints of selected alphabetical and numerical signs as well as phrases for emergency contexts from MSL. A database for the selected signs is developed wherein the sequential movements of the servo motor arrays are stored. The results showed that the system performed well as the selected signs can be understood by hearing-impaired individuals.

• The Bulletin of The Korean Astronomical Society
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• v.43 no.2
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• pp.34.1-34.1
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• 2018

We investigate the properties of bright galaxies with various morphological types in Abell 1139 and Abell 2589, using the pixel color-magnitude diagram (pCMD) analysis. The 32 bright member galaxies ($Mr{\leq}-21.3mag$) are deeply imaged in the g and r bands in our CFHT/MegaCam observations, as a part of the KASI-Yonsei Deep Imaging Survey of Clusters (KYDISC). We examine how the features of their pCMDs depend on galaxy morphology and infrared color. We find that the g - r color dispersion as a function of surface brightness (${\mu}r$) shows better performance in distinguishing galaxy morphology, than the mean g - r color does. The best set of parameters for galaxy classification appears to be a combination of the minimum color dispersion at ${\mu}r{\leq}21.2mag\;arcsec-2$ and the maximum color dispersion at $20.0{\leq}{\mu}r{\leq}21.0mag\;arcsec-2$: the latter reflects the complexity of stellar populations at the disk component in a typical spiral galaxy. Moreover, the color dispersion of an elliptical galaxy appears to be correlated with its WISE infrared color ([4.6]-[12]). This indicates that the complexity of stellar populations in an elliptical galaxy is related to its recent star formation activities. From this observational evidence, we infer that gas-rich minor mergers or gas interactions may have usually occurred during the recent growth of massive elliptical galaxies.