• Transactions of the Korean Society of Mechanical Engineers A
• /
• v.20 no.7
• /
• pp.2223-2233
• /
• 1996

The analytical solutions for the free vibration of cross-ply laminated composite cyllindrical shell with axial stiffeners(stringers) are presented usint the energy method. The stiffeners are taken to be smeared over the surface of shell with the smeared stffener theory. The effect of the parameters such as the stacking sequences, the shell thichness, the shell radius-to stringer depth ratio, the stringer depth-to width ratio, the shell length-to radius ratio are studied. By comparison with the previously published experimental results and the analytical results for the stiffened isotropic cylindrical shell and the unstiffened orthotropic composite laminated cylindrical shell, it is shown that natural frequencies can be determined with adequate accuracy.

• Journal of the Korean Society for information Management
• /
• v.22 no.2 s.56
• /
• pp.87-101
• /
• 2005

The diffusion of webpages has inevitably brought about changes in providing the information service of the medical libraries. Accordingly this study builds a theoretical background in relation to webpages and information services of the medical libraries. Also, this paper examines the current information services in the webpages of the medical libraries in Seoul. By so doing, this study aims to enhance the information service in webpages of the medical libraries.

• Proceedings of the Korean Society of Broadcast Engineers Conference
• /
• 2011.07a
• /
• pp.11-13
• /
• 2011

양방향 필터 (Bilateral filter)는 에지 보전 평활화 필터로써 디노이징, 반사 제거, 스테레오 매칭 등 다양한 분야에서 사용되고 있다. 이는 기존의 가우시안 필터에 사용되는 공간 도메인 커널 (spatial kernel)이외에 강도 도메인 커널 (range kernel)을 추가로 사용하여 비슷한 강도의 픽셀에 높은 가중치를 부여함으로써 에지를 보전하면서 평활화를 한다. 또한 양방향 필터는 비등방성 확산 필터 (Anisotropic diffusion filter)와 달리 항상 수렴을 보장한다. 따라서 본 논문에서는 고정점 반복 이론을 적용하여 양방향 필터의 수렴을 수학적으로 증명한다.

• The Journal of the Acoustical Society of Korea
• /
• v.10 no.3
• /
• pp.72-82
• /
• 1991

The Magnetic noise generated in three phase induction motor are investigated. Total noises measured by using JEM-1313 code and sound length method and the experimental formulae are derived of magnetic fk={K+$\frac{Z_s}{P}$(1-S)}f[Hz] noise is measured in the stator of induction motor except rotor supplied from power source and their datum are analyzed and compared with one another. The experimental value of magnetic noises are equal to the theoretical value at 1440[Hz] and 1560[Hz]. The biggest magnetic harmonic is generated at 1560[Hz].

• Journal of the Korean Operations Research and Management Science Society
• /
• v.33 no.1
• /
• pp.149-168
• /
• 2008

Many organizations have introduced information technology (IT) as an innovation to gain competitive advantages as business environments have become increasingly complex and rapidly changing. Despite the large investment of IT, there have been mixed results about whether IT creates business values. Considering that IT assimilation may play an important role in explaining IT productivity paradox, this study examines the formation of IT assimilation and its effect on the organizational performance. To do so, this study suggests a research model based on Innovation Diffusion Theory by incorporating organization system, communication channel, change acceptability, and innovation factors, and then attempts to empirically explore the role of IT assimilation for enhanced organizational performance using data collected at the organizational level. Structural equation analysis using AMOS provides significant support for part of proposed relationships. Specifically, we have found encouraging results on the role of IT assimilation by identifying its mediating effect on the organizational performance. Theoretical and practical implications of the findings are discussed accordingly.

• THE HEALTH and ORGANIC FARMING
• /
• no.231
• /
• pp.1-12
• /
• 2006

제28회 한국유기농업대회 준비돌입/환경호르몬으로부터 자유로워질수 있는 길/우리의 산야초/연속 강우에 따른 과일나무 잎의 갈변에 대하여/벼 멀칭재배의 이론과 기술/김제지평선축제, 성공적으로 개최돼/신태인 유기농 포도축제 성료/질병 예방을 위한 식사/일본,고령화와 웰빙 붐으로 건강식품시장 '폭발'/스위스,유기농가 급속 확산/LA,'건강빵'경쟁 후끈~후끈/일본,학교급식용 중국산 냉동가지 풋콩에서 잔류농약 검출/두가지 비료로 유기농작물의 고품질 다수확 생산을 체계적으로 보다 쉽게 하는 방법/전남도, 전국 최초 '친환경축산 5개년 종합계획'수립/배추 노균병 어떤 병인가?/고추.방울토마토 증수/중국 박람회 및 유기농장 연수기/"유기가공식품" 인증 법제화 추진/국내외 친환경 농축산물의 생산 및 인증 실태/친환경 유기낙농의 정착 방안/9월중 새식구 명단/농촌진흥청,토양전자지도,휴대폰 영농정보 제공/친환경인증기관협의회 출범/친환경농자재'목록공시제'시행/충주시,친환경바이오농업 확대 추진/제주,친환경농업 발전전략 심포지엄 개최/유기 및 일반 농산물의 품질 비교에 관한 연구/유기질 비료의 이해

• Journal of the Korean Society for information Management
• /
• v.17 no.3
• /
• pp.171-191
• /
• 2000

The development and diffusion of PC network have impact on civil administration service that has become part of our daily lives. This study constructs the theoretical background on the civil administration service, examines the development of it, investigates and analyzes the actual conditions based on its information structure and contents, and suggests some recommendations to enhance the service.

• Journal of the Korean Society for information Management
• /
• v.19 no.3
• /
• pp.189-210
• /
• 2002

As the access and the use of internet have been diffused in our daily life. internet addiction has been issued as a social pathological phenomenon. In this context, this study constructs a theoretical foundation on internet addiction based upon the understanding on internet and on addiction as a social phenomenon: examines the background of internet addiction in Korea: analyzes the cases of internet addiction as reported on newspapers; and explores the characteristics and the directions to cope with internet addiction. By so doing. this study aims at enhancing our understanding on internet addiction.

• Proceedings of the Korean Statistical Society Conference
• /
• 2003.10a
• /
• pp.213-218
• /
• 2003

본 논문은 혁신수용에 대한 한국인들의 군집화에 관한 연구로서, 분류된 군집의 라이프스타일 등의 특성을 밝힐 것이다. 연구를 위해 2003년 6월 9일부터 27일까지 설문조사를 실시하였으며, Ward의 군집분석 방법을 이하여 분석하였다. Rogers가 혁신 수용에 관한 군집을 통계적 이론을 바탕으로 다섯 가지로 분류한 바 있으나 본 연구에서는 혁신층이 11%, 조기다수층이 24.4%, 후기다수층이 48.9%, 후발수용층이 15.7% 등 네 가지 군집으로 분류될 수 있음을 알 수 있었고, 이 군집들의 라이프스타일을 연구하였다. 또한 Rogers의 연구 결과와 비교해 볼 때, 조기수용층이 혁신층으로 흡수되었다. 이러한 결과는 두터운 혁신층을 바탕으로 신제품이나 새로운 서비스를 처음 받아들이는 계층이 넓다는 것을 의미하고, 우리나라에서는 신제품을 개발 시험할 수 있는 좋은 구조를 가지고 있음을 의미하고, 반면에 조기다수층이 혁신 수용에 신중함으로 보이고 있기 때문에 혁신의 확산에 높은 저항이 있음을 알 수 있다. 세계각국에서 적극적으로 추진하고 있는 초고속 인터넷 서비스 분야 성공은 다른 나라에 비해 서비스를 빠르게 수용하고 이 후 높은 품질의 서비스와 고객만족을 기업들에 요구하고, 기업들의 적절한 대응의 결과로 설명될 수 있다.

• Proceedings of the Membrane Society of Korea Conference
• /
• 1997.10a
• /
• pp.27-30
• /
• 1997

1. Introduction : Molecular diffusion of small molecules in polymers plays an important role in many areas where polymers are acting as barriers, and in separation processes, such as selective diffusion. Different applications of polymers have different requirements on their transport properties. Therefore, reliable predictions of diffusion coefficients for small molecules in polymeric materials could be a useful tool to design appropriate materials. For many years, the theories based on free-volume concepts have been widely used to correlate and predict diffusion behavior in polymer/solvent systems. In the theory derived by Vrentas and Duda, the empty space between molecules that is available for molecular transport, referred to as hole free-volume, is being redistributed. Molecular transport will occur only when a free-volume of sufficient size appears adjacent to a molecule and the molecule has enough energy to jump into this void. The diffusive jump is considered complete when the void left behind is closed before the molecule returns to its original position. In this paper, the Vrentas-Duda free-volume theory is presented and the methods to estimate free-volume parameters for predicting polymer/ solvent diffusion coefficients are described in detail.