• 한국조명전기설비학회:학술대회논문집
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• 한국조명전기설비학회 2004년도 춘계학술대회 논문집
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• pp.570-574
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• 2004

Technical supply reason of digital base and important color reappearance of WEB base that is diffused rapidly on industry whole. Examined my outside factor investigation and revision method of inaccurate color reproduction and color reappearance valuation method influencing in color reappearance of monitor for last reception using in on-line shopping as well as end consumers in graphic age

• Steel and Composite Structures
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• 제23권3호
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• pp.273-283
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• 2017

In this paper, it is aimed to present a detail investigation related to structural behavior of laterally unrestrained steel cantilever roof of tribune with slender cross section. The structure is located in Tutak town in $A{\breve{g}}r{{\i}}$ and collapsed on October 25, 2015 at eastern part of Turkey is considered as a case study. This mild sloped roof structure was built from a variable I beam, and supported on steel columns of 5.5 m height covering totally $240m^2$ closed area in plan. The roof of tribune collapsed completely without any indication during first snowfall after construction at midnight a winter day, fortunately before the opening hours. The meteorological records and observations of local persons are combined together to estimate the intensity of snow load in the region and it is compared with the code specified values. Also, the wide/thickness and height/thickness ratios for flange and web are evaluated according to the design codes. Three dimensional finite element model of the existing steel tribune roof is generated considering project drawings and site investigations using commercially available software ANSYS. The displacements, principal stresses and strains along to the cantilever length and column height are given as contour diagrams and graph format. In addition to site investigation, the numerical and analytical works conducted in this study indicate that the unequivocal reasons of the collapse are overloading action of snow load intensity, some mistakes made in the design of steel cantilever beams, insufficient strength and rigidity of the main structural elements, and construction workmanship errors.

• 한국산학기술학회논문지
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• 제12권1호
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• pp.38-44
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• 2011

본 자원탐사의 중요성이 증대되고 있는 상황에서, 효과적인 자원탐사방법의 최적설계 및 탐사자동화가 중대 관심사가 되고 있다. 본 연구는 수치적인 모델링의 문제점을 해결하기 위하여, 현장의 환경을 하드웨어적으로 재현한 탐사환경 축소모형 로봇 시스템을 제안한다. 종래의 이동로봇 시스템을 개량하여 케이블카용 로봇시스템을 개발하였다. 본 시스템은 로봇의 자장 노이즈를 극소화시키고, 자장 그레디언트의 현장 측정 재현을 통하여 효과적인 설계지침을 제공한다. 또한 케이블카형 이동방법은 이용하여, 험지에서 탐사 자동화등에 활용될 수 있다.

• 한국전산유체공학회:학술대회논문집
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• 한국전산유체공학회 2008년도 춘계학술대회논문집
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• pp.51-53
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• 2008

The vehicle aerodynamic crosswind characteristics are mainly governed by the coefficient of side force and yawing moment. These performances affect not only the driving comfort which can be felt by driver but also the safety due to the instability of vehicle. The aims of this investigation are to improve the aerodynamic crosswind performance of sedan vehicle under the crosswind conditions. In order to improve the crosswind stability, numerical analysis has been performed by modifying the rear body shape of vehicle. As the results, we observed about 20% reduction of yawing moment coefficient relative to the base vehicle.

• 한국항해항만학회:학술대회논문집
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• 한국항해항만학회 2006년도 International Symposium on GPS/GNSS Vol.2
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• pp.391-394
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• 2006

The paper deals with the experimental GNSS receiver built at the Czech Technical University for experiments with the real GNSS signal. The receiver is based on software defined radio architecture. Receiver consists of the RF front end and a digital processor based on programmable logic. Receiver RF front end supports GPS L1, L2, L5, WAAS/EGNOS, GALILEO L1, E5A, E5B signals as well as GLONASS L1 and L2 signals. The digital processor is based on Field Programmable Gate Array (FPGA) which supports embedded processor. The receiver is used for various experiments with the GNSS signals like GPS L1/EGNOS receiver, GLONASS receiver and investigation of the EGNOS signal availability for a land mobile user. On the base of experimental GNSS receiver the GPS L1, L2, EGNOS receiver for railway application was designed. The experimental receiver is also used in GNSS monitoring station, which is independent monitoring facility providing also raw monitoring data of the GPS, EGNOS and Galileo systems via internet.

• Structural Engineering and Mechanics
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• 제81권6호
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• pp.737-750
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• 2022

Timber-Concrete Composite construction system consists of combining timber beam or deck and concrete with different connectors. Different fastener types are used in Timber-Concrete Composite systems. In this paper, the effects of two types of fasteners on structural behavior are compared. First, the notches were opened on timber beam, and combined with reinforced concrete slab by fasteners. This system is called as Notched Connection System. Then, timber beam and reinforced concrete slab were combined by new type designed fasteners in another model. This system is called as Notched-Slab Approach. Two laboratory models were constructed and bending tests were performed to examine the fasteners' effectiveness. Bending test results have shown that heavy damage to concrete slab occurs in Notched Connection System applications and the system becomes unusable. However, in Notched-Slab Approach applications, the damage concentrated on the fastener in the metal notch created in the slab, and no damage occurred in the concrete slab. In addition, non-destructive experimental measurements were conducted to determine the dynamic characteristics. To validate the experimental results, initial finite element models of both systems were constituted in ANSYS software using orthotropic material properties, and numerical dynamic characteristics were calculated. Finite element models of Timber-Concrete Composite systems are updated to minimize the differences by manual model updating procedure using some uncertain parameters such as material properties and boundary conditions.

• 한국과학교육학회지
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• 제24권6호
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• pp.1206-1215
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• 2004

본 연구에서는 오프라인과 온라인으로 진행된 물리탐구 토론에 참여한 학생들을 대상으로 실시된 설문과 면담을 통하여 온라인 물리탐구토론 학습체제에 대한 학생들의 인식을 알아보고, 이를 통하여 온라인 물리탐구토론 학습 체제의 특징을 알아보았다. 분석은 온라인 물리탐구토론 학습체제의 사용자 편리상 온라인 탐구토론의 비동시성, 글쓰기와 관련된 온라인 탐구토론, 온라인 탐구토론의 시각적 표현과 물리적 존재감, 온라인 탐구토론의 선호도의 다섯 가지 범주로 실시되었다. 학생들은 온라인 탐구토론에서 시공간을 초월하여 접근할 수 있고, 비동시성으로 인하여 충분한 사고 후에 논쟁에 참여할 수 있다는 점을 온라인 탐구토론의 가장 큰 장점으로 여기고 있었다. 또한 온라인 활동이 학생들 스스로의 참여로 수행되지만, 학생들의 활발한 참여를 위해서는 온라인 교육 시스템의 기술적인 부분이외에도 학부모와 교사의 역할이 더없이 중요하다.

• 열처리공학회지
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• 제15권6호
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• pp.269-271
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• 2002

For the investigation of the hardness profiles and distortion characteristics of SCM415 steel, test pieces of SCM415 steel were gas and vacuum carburizing treated. The hardness profiles and distortion characteristics of vacuum and gas carburized SCM415 steel show different results. Vacuum carburizing can offer more improved hardness profiles than alternate methods of carburizing. Compared to alternate methods of carburizing, vacuum carburizing can offer improved mechanical properties and reduced cycle times of the process.

• Structural Engineering and Mechanics
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• 제43권2호
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• pp.225-237
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• 2012

This paper presents an experimental investigation of the flexural behavior of square hollow steel section (HSS) beams subjected to pure bending. Totally six unfilled and nine ultra high performance concrete (UHPC)-filled HSS beams were tested under four-point bending until failure. The effects of the steel tube thickness, the yield strength of the steel tube and the strength of concrete on moment capacity, curvature, and ductility of UHPC-filled HSS beams were examined. The performance indices named relative ductility index (RDI) and strength increasing factor (SIF) were investigated with regard to different height-to-thickness ratio of the specimens. The flexural strengths obtained from the tests were compared with the values predicted by Eurocode 4, AISC-LRFD and CIDECT design codes. The results showed that the increase in the moment capacity and the corresponding curvature is much greater for thinner HSS beams than thicker ones. Eurocode 4 and AISC-LRFD predict the ultimate moment capacity of the all UHPC-filled HSS beams conservatively.

• 산업경영시스템학회지
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• 제7권10호
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• pp.35-45
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• 1984

1. The purpose of the study. The purpose of this study is to suggest the direction of educational curriculum for reinforcement of practical education of business management department in technical college. 2. The method of the study (1) The consciousness investigation of an undergraduate (2) The demand and supply program of human power in enterprise (3) An opinion of enterprise (4) An opinion of professor and school career (specialist) (5) On-the-spot practice (6) An educational curriculum 3. The suggestion and conclusion (1) An enterprise should collect graduate of technical college at the rate of fixed as a foreign (2) An opportunity of a going education and of proceeding to higher school at the rate of fixed should be provided (3) Buss management department in technical college should be subdivided and specialized (4) Industrial - educational cooperation complex should be realized and promoted stroghly.