• 조명전기설비학회논문지
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• 제21권5호
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• pp.106-111
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• 2007

반도체 공정에서 각 단계별 과정을 거친 후 dechucking시 wafer가 ESC(Electrostatic Chuck)로부터 방전되지 못하고, 잔류되어 있는 극성을 띤 전하(Electric charge)들에 의해 wafer와 ESC사이에 인력이 발생하여 wafer의 sliding, popping 및 wafer broken 등의 문제가 발생한다. 본 논문에서는 wafer와 ESC의 구성을 capacitor를 이용하여 modeling하고, PSpice를 사용하여 chucking system에 의한 wafer의 대전 현상을 모의하고 그 결과를 바탕으로 잔류전하를 방전시키기 위한 여러 가지 방법을 검토하여 최적의 잔류전하 제거 기법을 제시한다. 즉 별도의 전압원을 사용하여 (+)와 (-)를 교번하는 구형파를 인가함과 아울러 일정시간 동안 Plasma내에서 스위칭시킴으로써 ESC나 wafer에 charge되어 있는 극성을 띤 전하들을 중화(Neutralize) 시키도록 하였다. 그리고 이를 실제 하드웨어로 구현하여 실 공정에 적용한 결과를 제시한다.

• 한국조명전기설비학회지:조명전기설비
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• 제7권4호
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• pp.51-58
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• 1993

리니어 직류 모터의 고속, 고정도 위치제어에 대하여 포물선형 스위칭 함수에 최단시간 제어 방식을 제안하였다.제안한 방식은 간단한 구성으로 최단시간 제어를 실현한기 위하여 뱅-뱅 제어의 절환을 위상면에 설정한 포물선형 스위칭 함수상에서 행하는 것이다. 그러나 시스템의 모델링 오차등에 의하여 슬라이딩 모드를 발생시키므로 최단시간 제어를 위해 반복실험에 의하여 1회의 절환에 의한 뱅-뱅 제어를 실현하였다. 그 후 궤환 제어에 의하여 리니어 직류모터를 목표점에 정지시켰다.

• 한국산학기술학회논문지
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• 제16권2호
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• pp.1469-1476
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• 2015

산지가 전국토의 70%를 차지하는 국내 지형의 특성으로 인하여, 철도선로 전체 노선의 상당부분을 교량구간이 차지한다. 이에 따라 교량 설계 시 경제성 증가를 위하여 경간장을 늘리는 것이 유리하지만 궤도-교량 상호작용에 의한 레일의 부가축응력, 변위 등의 문제로 인한 제약이 발생한다. 본 연구에서는 궤도와 교량 상판 사이에 설치되는 슬라이딩 층을 고려한 궤도-교량 상호작용 해석을 수행하였다. 수치해석 결과를 통해 슬라이딩층 설치 방법에 따른 상호작용 거동을 분석하였으며, 궤도-교량 상호작용이 저감된 새로운 궤도-교량 구조시스템의 개발방향을 제안하였다.

• 대한안전경영과학회지
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• 제16권3호
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• pp.55-62
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• 2014

During five years (Year 2009~2013), Total victims of 72 %(81,560 people) and those 50.6 %(1,258 people) of death accident occurs in small scale construction site which operate 2 million USD less construction budget. Especially, falling death accident account for 785 people, in the share of 33.2 %(261 people) death disaster takes due to defect of original cause materials. The major safety issues in small scale work place take place while scaffold installation, disassembling, work-plate improper installation or non-professional skills of workers. Furthermore, labor subcontract systems make small construction site shortage of resources. Those workers regard work-plate as unnecessary and consumables supplies. Because of that most of workers use unsafe workplace in most construction site. Therefore, in order to prevent falling accident occurring in small scale work site, government should organize related regulations such as "Work site safety construction method" and then expands education support, financial aid, and sourcing safety supplies for work plate which offer broad variety experiences. Also, introduce certificate solutions for various work plates to improve safety function such as anchoring type method and anti sliding function.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2005년도 추계학술대회 논문집
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• pp.203-210
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• 2005

Rockey slopes adjacent to railways are disclosed from severe weathering and hazard of failure of themselves. Consequently it causes directly rockfall or landsliding on the railway. Conventional solutions-rigid system like rocksheds, shotcrete, retaining walls, etc to these causes are limited to protect train, rail, our properties and lives from the harmful attack - rockfall. debris flow and sliding. Flexible concept for solutions with passive and active type method based on Euro Code 7 capable of high energy absorption and light materials are rapidly replacing the rigid systems with natural friendly, early installation, cost and time saving and reducing danger in works all over the world.

• 한국공간구조학회논문집
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• 제13권2호
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• pp.57-66
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• 2013

There are a number of construction methods to build spatial structures such as erection method, Element method, Block method, Sliding method, Lift-up method and Push-up method. These methods are uneconomical and low accuracy, and require long construction duration because of a need of a scaffold or a tower crane to build spatial roof frame. In this study, the construction method to erect a truss structure was proposed as an economical and easy installation method. The proposed method has end hinges of keel truss and winches with horizontal cable. This method makes safe and accurate production and reduces construction duration because trusses are built on the floor or supporter. The goal of this study is to verify the validity of construction method by building scale model using the proposed method.

• KIEAE Journal
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• 제17권4호
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• pp.59-65
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• 2017

Purpose: Thermal performance and air tightness of window are improved for the building energy efficiency. As the deteriorated houses are increased, the improve measures with low cost and easy installation are developed in the energy performance of window. Attached glazing and windbreak can be easily applied to the window with low cost. In this paper, the effect of the attached glazing and windbreak on the thermal performance and air tightness of window is analyzed as the measure to improve performance of window. Method: Thermal transmittance of glazing is evaluated through WINDOW simulation according to thickness of attached glazing and air cavity. Based on the simulation results, thermal transmittance, air tightness and condensation resistance performance of four cases are tested according to Korea standards. One type of PVC sliding double window is chosen as the specimen. For the analysis on low performance of window, the outside of window is excluded in the PVC sliding double window. Result: This study shows that thermal performance of glazing can be increased by the application of attached glazing. Furthermore, lower thermal performance of glazing can obtain the higher effect of attached glazing. The application of attached glazing and windbreak can effect on increasing thermal performance and air tightness of window.

• 한국수산과학회지
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• 제41권3호
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• pp.215-220
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• 2008

This study examined the stability of cross- and box-type artificial reefs used to construct seaweed beds. Theoretical and experimental studies have clarified the Froude similitude. However, basic data needed to develop a more stable design for artificial reefs must be collected from long-term studies and analyses of sliding caused by waves. Hydraulic experiments are important for solving problems in the design and construction of artificial reefs. This study examined some design parameters for artificial reefs under wave and currents. The results showed the stability of cross- and box-type artificial reefs for constructing seaweed beds using a dimensionless parameter (the surf similarity parameter), water particle velocity, and so on. The hydraulics experiment indicated that the stability of artificial reefs differed according to their method of installation. This implies that artificial reefs should be installed after considering various environmental factors, such as wave breaking, reflection, and sediments.

• 한국생산제조학회지
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• 제24권1호
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• pp.7-14
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• 2015

The machine tools builders are trying to improve the efficiency and performance of the machine tools. The electro-mechanical driven broaching machine has many advantages such as lower noisy operating, higher energy efficiency, and smaller space of installation. This paper presents the structural and mechanical development of an electro-mechanical driven broaching machine that is replaced for traditional hydraulic one. The servo motor, ball screw and roller linear guide are used instead of hydraulic cylinder and translation frictional sliding guides. The simulation method based on FEM was applied to analyze the stress, deformation of the machine for static analysis. The dynamic analysis was carried out for verifying and assessing the mechanical behavior of the developed broaching machine. This work helps broaching machine developer make a better product at the early design stage with lower cost and development time.

• 한국디지털건축인테리어학회논문집
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• 제12권1호
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• pp.81-88
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• 2012

According to the survey results of the Ministry of Land, Transport and Maritime Affairs in the end of December 2011, the residential buildings was reported as 67.3% of 4,529,464 buildings. Reflected in the national energy policy, the residential building is expected that greater energy savings. To have realized the Passive House Project used the Autoclaved Lightweight Concrete(ALC) material on exterior wall, we take advantage of a very large energy savings. Therefore, this study investigate the patent documents of three major companies, SUMITOMO, CLION, ASAHI KASEI, in Japan. and analyze technical flow and benchmarking patent. As a result, the Sliding method or the Rocking method of ALC panels how to install is to be superior to high-performance drift and safety by a earthquake. And the embedded anchor in panel needs to improve the shape and the strength of bearing. Thus installation technology of the ALC exterior wall investigated in japanese patent documents is expected to the fastening units and anchors.