• Title/Summary/Keyword: Two-Frame

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A Theoretical Study on Free Gyroscopic Compass

  • Jeong, Tae-Gweon;Park, Sok-Chu
    • Journal of Navigation and Port Research
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    • v.30 no.9
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    • pp.729-734
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    • 2006
  • The authors aim to establish the theory necessary for developing the free gyroscopic compass and focus on mainly two points. One is to suggest north-finding principle by the angular velocity of the earth's rotation, and the other is to suggest orthogonal coordinate transformations of the motion rate of the spin axis, which transforms the components of motion rate in the free gyro frame into those in the platform frame and that this transformed rate is, in turn, transformed into the NED(north-east-down) navigation frame. Subsequently, ship's heading is obtained by using the fore-aft and athwartship components of the motion rate of the spin axis in the NED frame. In addition it was found how to solve the transformation matrix necessary for transforming each frame.

Development of Automatic Making System of a Frame Element for Flame Prevention (화염방지장치용 프레임 엘리멘트의 자동제작장치의 개발)

  • Kim, Gab-Soon
    • Journal of the Korean Society for Precision Engineering
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    • v.23 no.12 s.189
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    • pp.56-63
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    • 2006
  • This paper describes the development of automatic making system of a frame element for flame prevention. The frame element is made by turning a thin plate and a formed plate on the small pipe. The couple plate(two plates) should be pulled with constant farce to manufacture a good frame element. This is because if the gap between one couple plate and other couple plate is different, it will not prevent flame. In this paper, the automatic making system of a frame element for flame prevention was made, and which could automatically manufacture a frame element. The characteristic test of the made frame element by that system was performed, and its result was very good.

A Structural Analysis of C-Frame Press (C-Frame Press의 구조해석)

  • 박현기;황병복
    • Proceedings of the Korean Society for Technology of Plasticity Conference
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    • 1997.03a
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    • pp.257-260
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    • 1997
  • The high precision of the products manufatured by press forming requires the high stiffness of press machines. In this study, the C-frame type press is analyzed to provide the basic idea on the C-frame press design, especially on the frame design. The finite element method is applied for the analysis and the isotropic propertics of the frame material is also considered. The results are summarized in terms of stresses and displacement distributions. Also, the openback angle of the presses is compared with two different models. The CS-150 and ECS-150 models, which are presses model having 150 ton frame capacity relatively and produced by SSangYong precision Co. LTD, are applied for the analysis.

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Lagrangian Formulation of a Geometrically Exact Nonlinear Frame-Cable Element (기하 비선형성을 엄밀히 고려한 비선형 프레임-케이블요소의 정식화)

  • Jung, Myung-Rag;Min, Dong-Ju;Kim, Moon-Young
    • Journal of the Computational Structural Engineering Institute of Korea
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    • v.25 no.3
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    • pp.195-202
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    • 2012
  • Two nonlinear frame elements taking into account geometric nonlinearity is presented and compared based on the Lagrangian co-rotational formulation. The first frame element is believed to be geometrically-exact because not only tangent stiffness matrices is exactly evaluated including stiffness matrices due to initial deformation but also total member forces are directly determined from total deformations in the deformed state. Particularly two exact tangent stiffness matrices based on total Lagrangian and updated Lagrangian formulation, respectively, are verified to be identical. In the second frame element, the deformed curved shape is regarded as the polygon and current flexural deformations in iteration process are neglected in evaluating tangent stiffness matrices and total member forces. Two numerical examples are given to demonstrate the accuracy and the good performance of the first frame element compared with the second element. Furthermore it is shown that the first frame element can be used in tracing nonlinear behaviors of cable members.

Progressive Collapse Resistance of RC Frames under a Side Column Removal Scenario: The Mechanism Explained

  • Hou, Jian;Song, Li
    • International Journal of Concrete Structures and Materials
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    • v.10 no.2
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    • pp.237-247
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    • 2016
  • Progressive collapse resistance of RC buildings can be analyzed by considering column loss scenarios. Using finite element analysis and a static test, the progressive collapse process of a RC frame under monotonic vertical displacement of a side column was investigated, simulating a column removal scenario. A single-story 1/3 scale RC frame that comprises two spans and two bays was tested and computed, and downward displacement of a side column was placed until failure. Our study offers insight into the failure modes and progressive collapse behavior of a RC frame. It has been noted that the damage of structural members (beams and slabs) occurs only in the bay where the removal side column is located. Greater catenary action and tensile membrane action are mobilized in the frame beams and slabs, respectively, at large deformations, but they mainly happen in the direction where the frame beams and slabs are laterally restrained. Based on the experimental and computational results, the mechanism of progressive collapse resistance of RC frames at different stages was discussed further. With large deformations, a simplified calculation method for catenary action and tensile membrane action is proposed.

Design of Cell Frame Structure of Unit Cell for Molten Carbonate Fuel Cell Using CFD Analysis (CFD를 통한 용융탄산염 연료전지 단위전지용 셀 프레임 구조 설계)

  • LEE, SUNG-JOO;LIM, CHI-YOUNG;LEE, CHANG-WHAN
    • Transactions of the Korean hydrogen and new energy society
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    • v.29 no.1
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    • pp.56-63
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    • 2018
  • In this study, a $100cm^2$ cell frame for a molten carbonate fuel cell was designed using CFD analysis. Electrochemical reactions, gas flow, and the heat transfer in $100cm^2$ cell frame were modeled using COMSOL Multiphysics. Two design variables such as the height of the cell frame and the length of the gas input area were determined to obtain minimized temperature distribution and uniform gas distribution. With two design parameter such as height of the cell frame and the length of the gas flow channel, the temperature difference in the cell fame was decreased to $5^{\circ}C$ and the gas uniformity in the flow channel were achieved.

Ultimate Strength Testing of 3-D Steel Frame Subjected to Non-Proportional Loads (순차하중을 재하한 3차원 강뼈대 구조물의 극한강도 실험)

  • Kim, Seung Eock;Kang, Kyung Won
    • Journal of Korean Society of Steel Construction
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    • v.14 no.1
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    • pp.59-67
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    • 2002
  • The ultimate strength testing of a two-story, single-bay, and sway allowed space steel frame was performed. Considering a majority of large-scale frame tests in the past, only two-dimensional frames were experimentally studied. Therefore, three-dimensional experiment is needed to extend the knowledge of this field. The steel frame subjected to non-proportional vertical and horizontal load was tested. The load-displacement curve of the test frame is provided. The experiment results are useful for verification of the three-dimensional numerical analysis. The results obtained from 3D non-linear analysis using ABAQUS were compared with experimental data.

Finite element modeling of pre-damaged beam in concrete frame retrofitted with ultra high performance shotcrete

  • Xuan-Bach Luu
    • Computers and Concrete
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    • v.33 no.2
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    • pp.121-136
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    • 2024
  • In recent times, there has been a growing need to retrofit and strengthen reinforced concrete (RC) structures that have been damaged. Numerous studies have explored various methods for strengthening RC beams. However, there is a significant dearth of research investigating the utilization of ultra-high-performance concrete (UHPC) for retrofitting damaged RC beams within a concrete frame. This study aims to develop a finite element (FE) model capable of accurately simulating the nonlinear behavior of RC beams and subsequently implementing it in an RC concrete frame. The RC frame is subjected to loading until failure at two distinct degrees, followed by retrofitting and strengthening using Ultra high performance shotcrete (UHPS) through two different methods. The results indicate the successful simulation of the load-displacement curve and crack patterns by the FE model, aligning well with experimental observations. Novel techniques for reinforcing deteriorated concrete frame structures through ABAQUS are introduced. The second strengthening method notably improves both the load-carrying capacity and initial stiffness of the load-displacement curve. By incorporating embedded rebars in the frame's columns, the beam's load-carrying capacity is enhanced by up to 31% compared to cases without embedding. These findings indicate the potential for improving the design of strengthening methods for damaged RC beams and utilizing the FE model to predict the strengthening capacity of UHPS for damaged concrete structures.

The Classification of Fashion Frame and Fashion Image of Korean Women in their Twenties and Thirties (한국 20~30대 여성의 패션 프레임과 패션이미지 유형화)

  • Shin, Sae-Young;Kim, Young-In
    • Journal of the Korean Society of Costume
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    • v.63 no.4
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    • pp.118-131
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    • 2013
  • The purpose of this study is to take a look at the fashion frame of Korean women in their twenties and thirties to sort the actual fashion image and the ideal fashion image according to the fashion frame of Korean women in their twenties and thirties, and also to find out the standards and features that divide such a classification. For this study, we used the Q method, which is valued as an effective way to assess subjectivity. This helps to objectively classify the perception the fashion images of and the response to them as well. The analyzed materials were divided into two actual fashion frames and two ideal fashion frames, and classified them into 12 fashion image types in total, that is, six actual fashion images and six ideal fashion images, and we named each type of the fashion images and analyzed the features of each fashion image type through the in-depth Q workshop in which 14 professionals participated. The results of this study are as follows: First, the actual fashion frames of Korean women in their twenties and thirties was largely divided into 'Fashion Gold Girl', the fashion frame of mainstream and 'Indi-idol', the fashion frame of subcultures, and this was further divided into six fashion image types: 'Basic Casual', 'Vintage Performer', 'Easy Chic', 'Ladies' Look', 'City Office Girl' and 'Club Mania'. Second, the ideal fashion frame of Korean women in their twenties and thirties was divided into 'Urban Refinement', the fashion frame of the mainstream and 'Mismatched Style', the fashion frame of subcultures. It was also divided into six fashion image types: Power Fashion', 'Fashion Conservative', 'Semi-culture', 'Fashion Otaku', 'Sweet Darling' and 'Fashion Panic'. Third, The characteristics of the fashion images' colors are recognizable according to the type of fashion images.

Optimization of Frame Structures with Natural Frequency Constraints (고유진동수 제약조건을 고려한 프레임 구조물의 최적화)

  • Kim, Bong-Ik;Lee, Seong-Dae
    • Journal of Ocean Engineering and Technology
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    • v.24 no.6
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    • pp.109-113
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    • 2010
  • We present the minimum weight optimum design of cross sectional for frame structures subject to natural frequency. The optimum design in this paper employ discrete and continuous design variables and Genetic Algorithms. In this paper, Genetic Algorithms is used in optimization process, and be used the method of Elitism and penalty parameters in order to improved fitness in the reproduction process. For 1-Bay 2-Story frame structure, in examples, continuous and discrete design variables are used, and W-section (No.1~No.64), from AISC, discrete data are used in discrete optimization. In this case, Exhaustive search are used for finding global optimum. Continuous variables are used for 1-Bay 7-Story frame structure. Two typical frame structure optimization examples are employed to demonstrate the availability of Genetic Algorithms for solving minimum weight optimum of frame structures with fundamental and multi frequency.