• Proceedings of the Korean Geotechical Society Conference
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• 2010.09c
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• pp.72-77
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• 2010

The Incheon Bridge, which was opened to the traffic in October 2009, is an 18.4 km long sea-crossing bridge connecting the Incheon International Airport with the expressway networks around the Seoul metropolitan area by way of Songdo District of Incheon City. This bridge is an integration of several special featured bridges and the major part of the bridge consists of cable-stayed spans. This marine cable-stayed bridge has a main span of 800 m wide to cross the vessel navigation channel in and out of the Incheon Port. In waterways where ship collision is anticipated, bridges shall be designed to resist ship impact forces, and/or, adequately protected by ship impact protection (SIP) systems. For the Incheon Bridge, large diameter circular dolphins as SIP were made at 44 locations of the both side of the main span around the piers of the cable-stayed bridge span. This world's largest dolphin-type SIP system protects the bridge against the collision with 100,000 DWT tanker navigating the channel with speed of 10 knots. Diameter of the dolphin is up to 25 m. Vessel collision risk was assessed by probability based analysis with AASHTO Method-II. The annual frequency of bridge collapse through the risk analysis for 71,370 cases of the impact scenario was less than $0.5{\times}10^{-4}$ and satisfies design requirements. The dolphin is the circular sheet pile structure filled with crushed rock and closed at the top with a robust concrete cap. The structural design was performed with numerical analyses of which constitutional model was verified by the physical model experiment using the geo-centrifugal testing equipment. 3D non-linear finite element models were used to analyze the structural response and energy-dissipating capability of dolphins which were deeply embedded in the seabed. The dolphin structure secures external stability and internal stability for ordinary loads such as wave and current pressure. Considering failure mechanism, stability assessment was performed for the strength limit state and service limit state of the dolphins. The friction angle of the crushed stone as a filling material was reduced to $38^{\circ}$ considering the possibility of contracting behavior as the impact.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.15 no.7
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• pp.1621-1627
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• 2011

According to the KEC 2005 accreditation criteria, enough major courses in addition to mathematics, basic science, computer science, cultural studies are required to fulfill the program's goal. So it is hoped that students have to take mandatory major courses as well cultural studies. In this paper we considered the necessity of General Education Curriculum for Engineering Education by analyzing the several university's accreditation programs and suggested the desirable modeling of the General Education Curriculum.

• Journal of Engineering Education Research
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• v.15 no.5
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• pp.131-139
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• 2012

This paper emphasizes writing education for engineering students should be communication driven writing education based on KEC2005. Communication driven writing for engineering students is essentially same as Technical Writing(TW) developed on the basis of ABET. Considering the current writing capability of engineering students and social need for various types of writing, TW education should be divided into two courses: basic and advanced. This paper deals with contents of a basic TW course in Myongji University, as a model case of a basic TW course for engineering students. It underlines various methods of prewriting that should be stressed and practiced in the TW class, because the prewriting step in the writing process determines the overall direction and structure of an essay. In particular, this paper introduces Power Writing(PW) which uses the structure of a paragraph as a means for providing building-blocks for the essay, employing logic, and ordering information arrangement in a paragraph. This paper also deals with important guidelines about sentence structure and word selection and proposes various applications of TW such as resume, interview, proposal, report, and presentation as a latter part of the basic course. Finally this paper highlights the etics of writing, such as plagiarism and the basic principles of quotation.

• Journal of Engineering Education Research
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• v.15 no.5
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• pp.125-130
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• 2012

This study proposes content and instruction of leadership education based on the results of evaluation and analysis of leadership skill of present levels of students who registered for 'leadership development and training' course which is liberal arts elective course of the 'Accreditation Board of Engineering Education in Korea' and provides best practices to develop leadership skill and to attain academic achievement 2, 4, 6, 7 of 12 academic achievement required by KEC2005. To accomplish a purpose of the study, I divide leadership skill into technical skill, human skill and conceptual skill that suggested by Katz and then measure students' leadership skill. The contents of leadership education to develop and enforce three leadership skills are as follows. First, for developing technical skill, there is a need for systematic education of basic working experience relevant to a major field of study. Second, for developing human skill, there is a need for education of leadership, motivation, conflict management, communication, group dynamics and presentation etc. Third, for developing conceptual skill, there is a need for education of founding vision, business strategy and creative idea etc.

• International Journal of Highway Engineering
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• v.17 no.6
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• pp.97-104
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• 2015

PURPOSES : Expressways experience chronic and recurring congestion, especially during weekends and holidays, because of the increased demands for leisure-related travel. The alternatives to solve chronic and recurring congestion may be three-fold: (1) physical expansion of expressway capacities, (2) road pricing, and (3) temporal and spatial distribution of traffic demands. Among these, the third alternative may be the most cost-effective method for the Korea Expressway Corporation (KEC) that can be achieved by using the existing ITS infrastructure. METHODS : KEC initiated a pilot study in which the traffic on congested expressways was managed by providing traffic condition information (i.e., travel times) of neighboring national highways for taking detours via variable message signs (VMS). This study aimed to estimate the detour rate, and the two pilot studies on Seohaean and Yeongdong expressways yielded many benefits. RESULTS : It was revealed that the total length of congestion segments decreased by 7.8 km, and the average travel speed increased by 5.3 km/h. CONCLUSIONS : Based on these findings, it was concluded that the propagation of detour information via VMSs during congestion hours can help reduce congestion on expressways and increase the benefits of the entire network.

• Proceedings of the KIEE Conference
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• 1995.11a
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• pp.348-351
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• 1995

A modified silicon direct bonding method has been developed alloying an intimate contact between grooved and smooth mirror-polished oxide-free silicon wafers. A regular set of grooves was formed during preparation of heavily doped $p^+$-type grid network by oxide-masking und boron diffusion. Void-free bonded interfaces with filing of the grooves were observed by x-ray diffraction topography, infrared, optical. and scanning electron microscope techniques. The presence of regularly formed grooves in bending plane results in the substantial decrease of dislocation over large areas near the interface. Moreover two strongly misoriented waters could be successfully bonded by new technique. Diodes with bonded a pn-junction yielded a value of the ideality factor n about 1.5 and the uniform distribution of series resistance over the whole area of horded pn-structure. The suitability of the modified technique was confirmed by I - V characteristics of power diodes and reversly switched-on dynistor(RSD) with a working area about $12cm^2$. Both devices demonstrated breakdown voltages close to the calculation values.

• Journal of Sensor Science and Technology
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• v.7 no.1
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• pp.1-8
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• 1998

We have simulated the operating characteristics of the magnetotransistor(MAGFET) by the finite element method and suggested the optimum design conditions to get a maximum sensitivity, The magnetotransistor has been fabricated by CMOS standard processing according to the suggested design conditions and investigated its electromagnetic characteristics. The sensitivity of the magnetotransistor depends on the ratio of width(W) to length(L) of active area rather than its size, and has a maximum when W/L = 1. The relative sensitivity of a fabricated magnetotransistor was 2.53 %/T.

• Journal of Korea Port Economic Association
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• v.28 no.2
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• pp.179-194
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• 2012

In this study, we compared the efficiency of container terminals using DEA. To do this, we designed an AHP/DEA hybrid model using AHP and DEA, and evaluated the efficiency by comparing the container terminal operation company in Gwangyang(KEC, KIT, GICT) and Busan(HBCT, DPCT, KBCT, UPT, Gamman, PNC, PNIT, HJNC, HPNT). The proposed model can control the number of selected promising container terminal by applying DEA-AR model. This model can also improve the credibility of analysis by using objective weights through the AHP application to efficiency evaluation data and normalizing the evaluation data to apply AHP and DEA. The model assumes inputs to be container crane, transfer crane, yard tractor, and reach stacker and output as container traffic. The result shows that DPCT was an efficient DMU.

• International Journal of Highway Engineering
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• v.16 no.6
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• pp.69-78
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• 2014

PURPOSES : The purpose of this paper is showing that the state of pavement sublayers can be evaluated differently according to direction of FWD. METHODS : The concrete pavement slabs above subgrade without anything, subgrade with cavity, and box culvert were modeled by finite element method(FEM). The modeled pavements were analyzed by changing the direction of falling weight deflectometer(FWD). The deflection results obtained from FEM were used to calculate radius of relative stiffness and composite modulus of subgrade reaction using AREA method. Then, the analyzed results were compared to the results of the test performed at the Korea Expressway Corporation(KEC) test road. RESULTS : The composite modulus of subgrade reaction increased with subgrade elastic modulus, while radius of relative stiffness decreased. The pavement sections of pure earth showed the consistent results regardless of FWD direction. In case there was cavity, the radius of relative stiffness was larger and composite modulus of subgrade reaction was smaller when FWD was leaving the cavity than when approaching the cavity. This pattern became clear when the cavity got larger. In case of the section with box culvert, the pattern was opposite to the case of cavity. When the soil cover depth increased, the effect of box culvert got smaller. When the load was applied far from the cavity and box culvert, the effect was also declined. The test performed at the KEC test road showed identical results to those of finite element analysis. CONCLUSIONS : The direction of FWD should be considered in evaluation of the state of pavement sublayers because it can be evaluated differently even under identical condition.

• Journal of Engineering Education Research
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• v.12 no.2
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• pp.14-23
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• 2009

Most of the volunteering and community service had no direct link with classroom learning. Service-learning educational methodology that directly and intentionally integrates the classroom learning with service to the community. Research has found that this combination can improve the academic learning of the course material, give participants a deeper understanding of the social issues they address and provide valuable community services. And, service-learning has been offend environment to meet many of the KEC 2005 criteria that many be difficult to integrate into traditional engineering course. In studying, recognizing why service learning is a new attempt what is different form other learning experiences, we would like to search management strategies for service learning course and program development.