• Structural Engineering and Mechanics
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• 제4권2호
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• pp.111-124
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• 1996

New active "intelligent" structural systems with integrated self-sensing, diagnosis, and control capabilities can lead to a new design dimension for the next generation high-performance structures and mechanical systems. However, temperature effects to the piezoelectric transducers are not fully understood. This paper is concerned with a mathematical modeling and analysis of a laminated piezothermoelastic cylindrical shell composite exposed to mechanical, electric, and thermal fields. Generic shell equations and solution procedures are derived. Contributions of spatial and time components in the mechanical, electric, and temperature excitations are discussed, and their analytical solutions derived. A laminated cylindrical shell composite with fully distributed piezoelectric layers is used in a case study; its multi-field step and impulse responses are investigated. Analyses suggest that the fully distributed actuators are insensitive to even modes due to load averaging and cancellation. Accordingly, these even modes are filtered from the total response and only the modes that are combinations of m = 1, 3, 5, ${\cdots}$ and n = 1, 3, 5, ${\cdots}$ participating in dynamic response of the shell.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2006년도 6th International Meeting on Information Display
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• pp.1673-1675
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• 2006

As the manufacturing capacity needs for large size LCD TV shifts very fast into next generation, processing and test equipment makers face more difficult challenges in accommodating productivity, reliability and lead time of panel makers as well as the prerequisite of high process quality. In this paper, AKT will discuss its new innovative productivity solutions in PECVD (Plasma Enhanced Chemical Vapor Deposition), as the key thin film process system, and EBT (Electron Beam Test), as the key array test system, for the huge glass size with surface dimension larger than 2 meter by 2 meter.

• 신재생에너지
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• 제7권1호
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• pp.8-14
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• 2011

As is the case in Korea, the expansion of renewable energy dissemination is an essential matter in Ukraine when considering its energy consumption and dependence on energy import. While Korea has set about promoting the new and renewable energy industry on the back of the national policy on green growth, Ukraine expects a virtuous circle of renewable energy industry with green tariffs and the attraction of foreign capital in association with carbon emission trade. Utilizing its well-developed heavy industrial sector including the shipbuilding and automobile industries, Korea expects wind turbine manufacturing to become one of its next-generation growth engines. Ukraine is also trying to enter the wind turbine system or parts manufacturing industry based on its automobile industry and advanced aerospace technology. Although the Crimean region in Ukraine seems to have excellent wind resources, and thus shows great potential as a location for wind farm development, political instability has been a major obstacle to the attraction of foreign capital, leading to delayed investment.

• 산업경영시스템학회지
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• 제39권1호
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• pp.1-8
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• 2016

Patent management activities are considered to play a key role for technology-based firms under the recent knowledge-based economies. This is because intellectual property, including patents, can act as a system for continuous profit generation by protecting firms' products, processes and services. In Korea, healthcare industry is now regarded as one of the promising next generation industries. Despite the promise of healthcare industry, Korean healthcare product manufacturers are faced with turbulent business changes, such as market opening. Even though there are various industrial studies on the effect of patent management activities on firm outcome, previous studies have hardly paid attention to Korean healthcare product manufacturing firms. For this reason, this study identifies the effect of patent management activities, such as patenting activeness, technical excellence and cooperation degree, on firm outcomes, including financial profitability and firm growth, with respect to the Korean healthcare product manufacturers. In this study, we located 86 Korean healthcare manufacturing firms from KORCHAMBIZ and DART, and then collected the data of their patenting activities and outcomes between 2001 and 2013. By applying factor analysis and regression analysis, our empirical study found that firms' patenting activeness has the significant positive relationship on firms' financial profitability, and firms' patenting activeness and technical excellence have the significant positive relationship on firms' financial growth. Our study is an initial attempt to identify the effect of patent management activities on firm outcome within Korean healthcare product manufacturing industry, and thus its results can be used as the basis to formulate national policies for Korean healthcare product industry.

• 한국공작기계학회:학술대회논문집
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• 한국공작기계학회 2004년도 춘계학술대회 논문집
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• pp.269-274
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• 2004

As next generation display, TFT LCD gets into the spotlight, and the bigger glass size is required. Currently, its display size is 1500 mm by 1870 mm at the six generation comparing with 300mm by 400 mm at the first one and the size is increasing continuously, which cause the difficulties to apply the cleaning operation including the general brush cleaning. In this study, water-jet cleaning operation has been introduced, which spent the less water them other cleaning methods. Throughout the experiment, is has been found the possible damage of the declined cell and the variation of the tilt bias angle depending upon the increasing time. In addition, the simulation predicts the glass bending of the display.

• KIEE International Transactions on Electrophysics and Applications
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• 제5C권1호
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• pp.14-17
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• 2005

In this paper, an automated methodology for generating model parameters considering real manufacturing processes is presented with verified results. In addition, the outcomes of applications to the next generation of flash memory devices using the parameters calibrated from the process specification decision are analyzed. The test vehicle is replaced with a well-calibrated TCAD simulation. First, the calibration methodology is introduced and tested for a flash memory device. The calibration errors are less than 5% of a full chip operation, which is acceptable to designers. The results of the calibration are then used to predict the I-V curves and the model parameters of various transistors for the design of flash devices.

• 한국기계가공학회지
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• 제14권3호
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• pp.15-20
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• 2015

After the US government declared 3D printing technology a next-generation manufacturing technology, there have been many practical studies conducted to expand 3D printing technology to manufacturing technologies, called AMERICA MAKES. In particular, the Keck Center, located at the University of Texas at El Paso, has studied techniques for easily combing the 3D stacking process with space mobility and expanded these techniques to simultaneous staking techniques for multiple materials. Additionally, it developed convergence manufacturing techniques, such as direct inking techniques, in order to produce a module structure that combines electronic circuits and components, such as CUBESET. However, in these studies, it is impossible to develop a unified system using traditional independent through simple sequencing connections. This is because there are many problems in the integration between the stacking modeling of 3D printers and post-machining, such as thermal deformations, the precision accuracy of 3D printers, and independently driven coordinate problems among process systems. Therefore, in this paper, the integration method is suggested, which combines these 3D printers and subsequent machining process systems through an Internet-based cloud. Additionally, the sequential integrated system of a 3D printer, an NC milling machine, machine vision, and direct inking are realized.

• 마이크로전자및패키징학회지
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• 제30권2호
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• pp.43-51
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• 2023

본 논문에서는 전기차 전력변환 시스템의 근간이 되는 전력반도체 소자의 발전 방향과 차세대 전력반도체 소자인 wide bandgap (WBG)의 특징에 관해 소개하고자 한다. 현재까지의 주류인 Si insulated gate bipolar transistor (IGBT)의 특징에 관해 소개하고, 제조사 별 Si IGBT 개발 방향에 대해 다루었다. 또한 대표적인 WBG 전력반도체 소자인 SiC metal-oxide-semiconductor field-effect transistor (MOSFET)이 가지는 특징을 고찰하여 종래의 Si IGBT 소자 대비 SiC MOSFET이 가지는 효용 및 필요성에 대해 서술하였다. 또한 현 시점에서의 GaN 전력반도체 소자가 가지는 한계 및 그로 인해 전기자동차용 전력변환모듈 용으로 사용하기에 이슈인 점을 서술하였다.

• Composites Research
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• 제28권2호
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• pp.46-51
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• 2015

본 연구에서는 차량용 본넷의 구조 설계 및 해석을 수행하였다. 구조 설계를 위해 아마/비닐 에스테르 복합재료가 적용되었다. 아마 섬유 복합재 본넷의 제조공법은 VARTML(Vacuum Assisted Resin Transfer Molding-Light) 제조공법이 적용하였다. VARTML 공법은 한쪽 면은 견고한 금형을 사용하고 다른 면은 진공과 함께 유연한 금형을 사용하여 압력차를 이용하여 내부에 적층된 섬유에 수지를 신속하게 함침 시켜 성형하는 방법이다. 아마/비닐 에스테르 패널로 부터 시편을 가공하여 재료의 기계적 물성치를 획득하기 위한 시편 시험을 수행하였다. 이를 기반으로 자동차 본넷의 구조 설계를 수행하였다.

• 한국기계가공학회지
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• 제9권5호
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• pp.64-69
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• 2010

This study is the machining of fuel supply pipe used in large vessels. The fuel supply pipe of large vessels have effects to reduce engine exhaust because of common rail system and show excellent fuel efficiency so it is in the limelight as a vessel engine of next generation. At present, the shape of fuel supply pipe of common rail used for huge two-stroke & low-speed vessels is like a peanut hole so the second machining is necessary after the first machining. There is high error rate for machining and the materials waste caused by machining error is serious. Also, in this time the request for increasing the length of fuel supply pipe is suggested in the world market, it's judged that current methods will show higher error rate for machining. Therefore, the purpose of this study is to improve the machining process used originally. For that, the system controlling the process was developed as well as surface roughness and straightness which are evaluation items of fuel supply pipe were measured so that improved process can be observed in real time.