• Title/Summary/Keyword: 단순 가정법

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Undamped Dynamic Response of Anisotropic Laminated Composite Plates and Shell Structures using a Higher-order Shear Deformation Theory (비등방성 복합적층판 및 쉘의 고차전단변형을 고려한 비감쇄 동적응답)

  • Yoon, Seok Ho;Han, Seong Cheon;Chang, Suk Yoon
    • Journal of Korean Society of Steel Construction
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    • v.9 no.3 s.32
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    • pp.333-340
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    • 1997
  • This paper will expand the third-order shear deformation theory by the double-Fourier series and reduce to the solution of a system of ordinary differential equations in time, which are integrated numerically using Newmark's direct integration method and clarify the undamped dynamic responses for the cross-ply and antisymmetric angle-ply laminated composite plates and shells with simply supported boundary condition. Numerical results for deflections are presented showing the effect of side-to-thickness ratio, aspect ratio, material anisotropy, and lamination scheme.

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Buckling analyses of flat plates through two-element plate concept by using finite element method (유한요소법을 이용한 분할판 개념하의 평판 좌굴해석)

  • 민철기;손원기;주재현;류시융
    • Computational Structural Engineering
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    • v.8 no.3
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    • pp.79-89
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    • 1995
  • Two-element plate concept is incorporated into the buckling problem in order to simplify the nonlinear distribution of stress through the thickness of plate. Finite element formulations and programs based upon the Reissner functional and the modified Reissner functional using two-element plate concept are developed for buckling analysis of plates under axial compression. The two programs have been applied to obtain the linear elastic buckling behavior of axially compressed flat plates. Excellent agreement of linear elastic-solution results with exact or approximate solutions of other authors for the same boundary conditions proves the validity of the finite element method using two-element plate theory.

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A Logit Model for Repeated Binary Response Data (반복측정의 이가반응 자료에 대한 로짓 모형)

  • Choi, Jae-Sung
    • The Korean Journal of Applied Statistics
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    • v.21 no.2
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    • pp.291-299
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    • 2008
  • This paper discusses model building for repeated binary response data with different time-dependent covariates each occasion. Since repeated measurements data are having correlated structure, weighed least squares(WLS) methodology is applied. Repeated measures designs are usually having different sizes of experimental units like split-plot designs. However repeated measures designs differ from split-plot designs in that the levels of one or more factors cannot be randomly assigned to one or more of the sizes of experimental units in the experiment. In this case, the levels of time cannot be assigned at random to the time intervals. Because of this nonrandom assignment, the errors corresponding to the respective experimental units may have a covariance matrix. So, the estimates of effects included in a suggested logit model are obtained by using covariance structures.

Study of the Soilnail-Slope Design Method Considering Bending Resistance of Soilnail (휨저항을 고려한 쏘일네일보강사면의 해석에 관한 연구)

  • Joo, Yong-Sun;Kim, Nak-Kyung;Kim, Sung-Kyu;Park, Jong-Sik
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.28 no.6C
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    • pp.331-338
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    • 2008
  • Soil nailing is used as a method of slope stabilization and excavation support. The design method of soil nail are based on experience or assumption of interaction between soil and reinforcement. Most design methods simply considers the tension of reinforcement for analysis of slope stabilization. Soil nails interact with soils under combined loading of shear and tension. Jewell & Pedley suggested a design equation of shear force with bending stiffness and discussed that the magnitude of the maximum shear force is small in comparison with the maximum axal force. However, they have used a very conservative limiting bearing stress on nails. This paper discusses that the shear strength of soil nails should not be disregarded with proper bearing stresses on nails. The modified FHWA design method was proposed by considering shear forces on nails with bending stiffness.

Policing for Juvenile Delinquency in Korea (청소년범죄에 대한 경찰활동)

  • Lee, Ha-Sub;Jo, Hyun-Bin
    • The Journal of the Korea Contents Association
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    • v.11 no.7
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    • pp.285-297
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    • 2011
  • At recent years, juvenile crime that occurred, that young people have done incredibly cruel and serious intelligence community is making a serious scandal. The relationship between parents and youth crime under the influence of family environment factors and the hypothetical failure of school maladjustment and school factors due to contact with friends, around the area due to hazardous environment, local surroundings and social factors that committed a crime by were Juvenile crime in the real statistics on the rise again, starting the year 2005, and is increasingly young, violent crimes showed a high percentage increases. In order to prevent juvenile crime, these homes, schools, community work together to raise sustainable alternatives are needed. The police, as well as the maintenance of law and institutions, cooperation of youth organizations, increasing activity, such as removing harmful environmental youth leadership program, the flight needs to be improved. Today, juvenile crime is not simply a matter of police activities, school-linked program, police, community-linked programs, such as police comprehensive preparedness and commitment of the authorities is required.

Information Appliance Control MultiAgentsystem (정보가전 제어 멀티에이전트시스템)

  • 김일연;송준현;김일곤
    • Proceedings of the Korea Inteligent Information System Society Conference
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    • 2002.11a
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    • pp.363-369
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    • 2002
  • 가정 내에서의 초고속망 이용이 활성화되면서 가정 내에서의 활동은 매우 다양하고 복잡하며 그에 따른 서비스도 여러 가지 형태가 존재한다. 외부 인터넷망과 연동되는 홈 네트워크의 개념이 생기기 전부터 흠 오토메이션, 홈시큐리티 등의 서비스를 제공하기 위한 고립적인 형태의 망과 서비스 제공 시스템이 있었다. 월드 와이드 웹 서비스를 기본으로 한 인터넷의 폭발적인 활성화와 고속 인터넷망의 확산에 따라 가정 내에서 제공되는 서비스를 인터넷과 연계시키려는 시도가 보편화되었고 가정 내에서 사용되는 독립적인 기기들을 인터넷에 연결하여, 외부의 정보를 이용해서 활용하거나, 가전내의 기기들을 외부에서 액세스할 수 있게 되었다. 이렇게 하여 보다 풍부한 서비스를 제공하고, 사용상의 시간적인 제약을 완화할 수 있다. 예들 들어 인터넷상에서 조리법을 전송받아 전자레인지를 작동할 수 있으며, 외부에서 잘못 켜둔 가스밸브를 잠글 수도 있다. 가정 내에서 wrhd되던 이러한 서비스들은 서로 다른 하드웨어와 통신방법을 사용하고 있어, 이러한 서비스를 통합하여 운영, 관리할 수 있도록 하는 흠 서버의 개념이 대두되었다. 외부 인터넷 망과 연계된 흠 오토메이션, 홈 시큐리티등을 제공할 수 있는 기반이 마련되었고, 가정 내에서 독립적으로 제공되던 서비스들을 단일 홈 서버를 통해서 관리하려는 시도가 진행되었다. 그러나 홈 서버는 개발하는 업체의 보유기술에 따라 중심기능은 약간씩 차이를 보이고 있다. 홈 서버 응용 영역은 전문 지식을 소유한 인력과의 연계가 필요하고, 다양한 서비스 영역 행위가 아주 복잡하기 때문에 이들을 연결해 주는 자치 시스템을 필요로 한다. 또한 홈 서버 서비스 영역에서 정보는 각 영역 전문가가 가진 지식의 전달을 필요로 하기 때문에, 지식을 주고받는 멀티 에이전트의 시스템의 활용 영역으로 적당하다. 멀티 에이전트 시스템은 분산된 환경에서 에이전트간에 에이전트 통신 언어를 사용해서 대화를 하기도 하고, 상호 협력하는 에이전트들로 구성된 시스템을 뜻하며 흠 서버처럼 동적이고 고도의 자치성을 요구하는 영역에 적당하다. 멀티 에이전트 플랫폼으로는 FIPA(Foundation for Intelligent Physical Agents)가 제시한 에이전트 표준 플랫폼이 1997년부터 2000년에 이르기까지, 계속적으로 변화, 발전하고 있다. 본 연구는 FIPA에서 제시하는 플랫폼을 기반으로 홈 서버에 정보가전을 제어하는 에이전트를 두고 외부에서 다른 에이전트가 홈 서버에 위치하는 에이전트와의 통신을 통하기 정보가전을 지능적으로 제어하도록 하였다. 정보가전 에이전트는 가정 내 가전제품을 외부에서 제어하기 위한 에이전트이다. 단순한 관리가 아닌 에이전트로 하여금 지능적으로 가전제품 관리를 하게 한다. 정보가전 에이전트는 홈 서버에서 작동하는 에이전트와 PDA에서 작동하는 에이전트로 구성된다. 정보가전 에이전트는 전력량, 수도 사용량 제어와 가전제품 제어 기능과 보안 관련 서비스를 제공한다. 두 에이전트는 FIPA에서 정의된 규격에 맞게 만들어지기 때문에 FIPA명세서를 따르는 다른 에이전트와 자유로운 통신이 가능하다.

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Noble Women's Culture and Perception of Incense and Herbs in the Late Joseon Dynasty based on 『Gyuhap Chongseo』, 「BongimCheok」 (『규합총서』 「봉임측」에 나타난 조선후기 사대부 여성의 향문화(香文化)와 인식)

  • HA Sumin
    • Korean Journal of Heritage: History & Science
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    • v.57 no.3
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    • pp.38-54
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    • 2024
  • This paper examines how noblewomen during the Joseon Dynasty perceived incense and herbs, focusing on the 『Gyuhap Chongseo(閨閤叢書)』 a compendium edited by Yi Bingheogak(李憑虛閣, 1759~1824). The 『Gyuhap Chongseo』 is a classified collection of knowledge deemed essential for managing a noble household. By analyzing the content related to incense and herbs focused on 「Bongim Cheok」. This study reveals Yi Bingheogak's practical and realistic understanding of incense and herbs. For Yi, incense and herbs transcended mere cosmetic applications and luxury and served as indispensable tools in health and hygiene and domestic skills for traditional household management. While it may be challenging to generalize the perception of noblewomen solely based on the 『Gyuhap Chongseo』 the consistent transcription and transmission of the text suggest it resonated with the noblewomen's sentiments. With limited records left by noblewomen themselves, this study primarily explores Yi Bingheogak's perspective, who provided detailed knowledge and applications of incense and herbs across the compendium's sections. This reflects Yi's intention to broaden women's knowledge and cultural literacy, and contribute to improved quality of life through practical knowledge. This study demonstrates Yi's recognition of incense and herbs as vital commodities for the operation of domestic life, and illustrates how noblewomen of the Joseon Dynasty actively contributed to society and the household through knowledge and practical activities. The use of incense and herbs for beauty and domestic knowledge in various fields of traditional knowledge underscores a comprehensive understanding of noblewomen's perception and use of incense and herbs during the Joseon Dynasty.

Derivation of Reverse-Time Migration Operator as Adjoint Operation (어드조인트 연산으로서의 역시간 구조보정 연산자 유도)

  • Ji, Jun
    • Geophysics and Geophysical Exploration
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    • v.10 no.2
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    • pp.111-123
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    • 2007
  • Unlike the conventional reverse time migration method which is implemented by simply extrapolating wavefield in reverse time, this paper presents a derivation of another reverse time migration operator as the exact adjoint of the presumed forward wavefield extrapolation operator. The adjoint operator is obtained by formulating the forward time extrapolation operator in an explicit matrix equation form and then taking the adjoint to this matrix equation followed by determining the corresponding operator. The reverse time migration operator as the exact adjoint to the implied forward operator can be used not only as a migration algorithm but also as an adjoint operator which is required in the imaging through an inversion such as least-squares migration.

Effect of Fluid Added Mass on Vibration Characteristics and Seismic Responses of Immersed Concentric Cylinders (유체속에 잠긴 동축원통 구조물의 진동특성 및 지진응답에 대한 유체부가질량 영향)

  • 구경회;이재한
    • Journal of the Earthquake Engineering Society of Korea
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    • v.5 no.5
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    • pp.25-33
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    • 2001
  • For the seismic design and analysis of LMR(liquid metal reactor) being developed in Korea, it is necessary to develop the simple seismic analysis model including the fluid-structure interaction effects. In this paper, the theoretical backgrounds for the fluid added mass of the immersed concentric cylinders are investigated and the seismic analysis code using the Runge-Kutta algorithm, which can consider the fluid added mass matrix in system matrix, are developed to perform the time history seismic analysis. Form the coupled modal analysis and the seismic analysis for the simple immersed concentric cylinders, it is verified that the fluid added mass significantly affect the vibration characteristics and the seismic responses. Therefore the fluid coupled effects should be carefully considered in seismic response analysis of the immersed concentric cylinders.

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A Study on Elastic Shear Buckling Coefficients of Horizontally Curved Plate Girder Web Panels (강곡선 플레이트거더 복부판의 전단좌굴계수에 관한 연구)

  • Lee, Doo-Sung;Lee, Sung-Chul
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.28 no.3A
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    • pp.367-373
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    • 2008
  • In the design of horizontally curved plate girder web panels, it is required to evaluate accurately the elastic buckling strength under pure shear. Currently, elastic shear buckling coefficients of curved web panels stiffened by transverse intermediate stiffeners are determined by assuming conservatively that straight web panels without curvature are simply supported at the juncture between the flange and web. However, depending upon the geometry and the properties of the curved plate girder, the elastically restrained support may behave rather closer to a fixed support. The buckling strength of curved girder web is much greater (maximum 38%) than that of a straight girder calculated under the assumption that all four edges are simply supported in Lee and Yoo (1999). In the present study, a series of numerical analyses based on a 3D finite element modeling is carried out to investigate the effects of geometric parameters on both the boundary condition at the juncture and the horizontal curvature of web panel, and the resulting data are quantified in a simple design equation.