• Structural Engineering and Mechanics
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• 제62권1호
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• pp.85-95
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• 2017

This paper presents an explicit analytical iteration method for form-finding analysis of suspension bridges. By extending the conventional analytical form-finding method predicated on the elastic catenary theory, two nonlinear governing equations are derived for calculating the accurate unstrained lengths of the entire cable systems both the main cable and the hangers. And for the gradient-based iteration method, the derivation of explicit calculation for the Jacobian matrix while solving the nonlinear governing equation enhances the computational efficiency. The results from sensitivity analysis show well performance of the explicit Jacobian matrix compared with the traditional finite difference method. According to two numerical examples of long span suspension bridges studied, the proposed method is also compared with those reported approaches or the fundamental criterions in suspension bridge structural analysis, which eventually confirms the accuracy and efficiency of the proposed approach.

• Structural Engineering and Mechanics
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• 제5권6호
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• pp.775-784
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• 1997

A unified theory is presented for the shape analysis of curved surface with a single layer structure composed by frame, membrane or shell. The shapes produced by the theory have no shear stress in elements, and the stress states in the whole shape are as uniform as possible under an ordinary load. The theory starts from defining an element potential function expressed by the measurement of the element length or the element area. Therefore, the shape analysis can produce various forms according to the definition of the potential function, and each of those form or the cable net form with the potential function of the second power of element length is simply gotten by the linear analysis. The form in tensile stress is mechanically equal to an isotropic tension form.

• 대한수학회논문집
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• 제32권1호
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• pp.85-92
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• 2017

We give expressions of a biquaternion and research operations and calculations of each form of a biquaternion. Also, we investigate representations and properties of exponential and trigonometric forms of a biquaternion.

• 전기의세계
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• 제25권5호
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• pp.75-78
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• 1976

The most difficult problem encountered in impulse test of transformer is the determination of exact fauly for coil layer short. This paper is to establish one of improved standards in the above case by means of wave form analysis, based on the equivalent circuits and experimental investigation. During the fault occurs, the local oscillation in fault circuit is applicable where as the reflection wave is utilized to the main circuit. The result current wave form at neutral impeadance point is similar to the wave form by impulse test and has the singular wave form respectively.

• International Journal of Concrete Structures and Materials
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• 제9권1호
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• pp.21-33
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• 2015

This study aimed to present a reinforced concrete block system that reduces the flange thickness of the existing form block used in new buildings and optimizes the web form, and can thus capable of being used in the seismic retrofit of new and existing buildings. By conducting a compression test and finite element analysis based on the block and grouted concrete strength, it attempted to determine the compression capacity of the form block that can be used in new construction and seismic retrofit. As a result, the comparison of the strength equation from Architectural Institute of Japan to the prism compression test showed that the mortar coefficient of 0.55 was suitable instead of 0.75 recommended in the equation. The stress-strain relation of the block was proposed as a bi-linear model based on the compression test result of the single form block. Using the proposed model, finite element analysis was conducted on the prism specimens, and it was shown that the proposed model predicted the compression behavior of the form block appropriately.

• Structural Engineering and Mechanics
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• 제11권2호
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• pp.221-236
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• 2001

A local point interpolation method (LPIM) is presented for the stress analysis of two-dimensional solids. A local weak form is developed using the weighted residual method locally in two-dimensional solids. The polynomial interpolation, which is based only on a group of arbitrarily distributed nodes, is used to obtain shape functions. The LPIM equations are derived, based on the local weak form and point interpolation. Since the shape functions possess the Kronecker delta function property, the essential boundary condition can be implemented with ease as in the conventional finite element method (FEM). The presented LPIM method is a truly meshless method, as it does not need any element or mesh for both field interpolation and background integration. The implementation procedure is as simple as strong form formulation methods. The LPIM has been coded in FORTRAN. The validity and efficiency of the present LPIM formulation are demonstrated through example problems. It is found that the present LPIM is very easy to implement, and very robust for obtaining displacements and stresses of desired accuracy in solids.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2005년도 추계 학술논문 발표대회
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• pp.149-155
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• 2005

Lately Construction industry depressed by hard construction market condition. So Construction company, especial at this time, make more rationalize the management of inside Company and Construction field. So in this study we are to present the method of calculation reasonable duration at Reinforced Concrete Work. For the study first make up a question at field workers, then sampling the Form workers based the question. Second, We are using Work Analysis Method analysing the worker's work-method and Time. And then using the result of analysis, measure the Productivity of Form work. The productivity of Form work is used the basic data of duration at Reinforced Concrete Work

• 한국생활과학회지
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• 제7권2호
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• pp.63-73
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• 1998

To get well-fitted ready-made clothings with beautiful silhouettes, it's better to classify body forms into several forms and to assign sizing within each form than to grade just based on body size regardless of body styles. This study illucidated the importance of drop value in the results of surveying the current values of sizing and grading. Therefore, it's meaningful to get the classification of body form with appropriate distribution of drop values of the body, and the distribution of drop value and the frequency of each form is very helpful to name the combined sizing or coverage of ready-made clothes. This study aimed at classifying body forms with various drop values using multivariate analysis for sizing and grading. Factor analysis and cluster analysis were done using measured values from 346 unmarried women. The results are as follows: 1. The factor which explains body forms was obtained by factor analysis, and the representative major 18 items which have important roles in classifying body forms were selected among the measured values with high factor loading and communality. 2. The body forms were classified into 8 groups based on the charateristics, frequencies and distributions of them obtained from cluster analysis. 3. Each classified body form showed conspicuous difference in drop value and the difference of body form mainly resulted from the difference between waist and hip rather than the difference between bust circumference and waist in Korean unmarried women.

• Computers and Concrete
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• 제16권2호
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• pp.287-309
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• 2015

FormWorks-Plus is a generalized public domain user-friendly preprocessor developed to facilitate the process of creating finite element models for structural analysis programs. The lack of a graphical user interface in most academic analysis programs forces users to input the structural model information into the standard text files, which is a time-consuming and error-prone process. FormWorks-Plus enables engineers to conveniently set up the finite element model in a graphical environment, eliminating the problems associated with conventional input text files and improving the user's perception of the application. In this paper, a brief overview of the FormWorks-Plus structure is presented, followed by a detailed explanation of the main features of the program. In addition, demonstration is made of the application of FormWorks-Plus in combination with VecTor programs, advanced nonlinear analysis tools for reinforced concrete structures. Finally, aspects relating to the modelling and analysis of three case studies are discussed: a reinforced concrete beam-column joint, a steel-concrete composite shear wall, and a SFRC shear panel. The unique mixed-type frame-membrane modelling procedure implemented in FormWorks-Plus can address the limitations associated with most frame type analyses.

• 감성과학
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• 제12권2호
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• pp.233-242
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• 2009

최근 사용자 중심의 디자인과 형태개발 및 분석은 성공적 디자인의 중요한 방법론으로 부각되고 있다. 사용자의 형태분석을 위해서는 기존 방법의 통합적인 접근과 더불어 디자이너의 전문도구로서 고찰되고 개발되는 것이 요구된다. 특히 기존의 분석도구들은 디자이너의 요구에 적합할 수 있도록 분석결과의 시각화과 명확한 방향성 제시가 요구되며, 사용자 감성반응을 형태분석에 응용할 수 있는 다각적인 방법의 모색이 요구된다. 또한 분석도구로서의 전문성을 강화하고 디자이너가 손쉽게 사용할 수 있도록 디자이너 친화적 인터페이스의 적용이 필요하다. 본 연구는 사용자 감성반응을 기존의 형태분석 도구에 활용하기 위한 방법과 체계를 분석하며, 이를 통하여 사용자의 감성적 반응에 기초한 형태분석 도구를 제시하였다. 구체적인 형태분석의 도구는 통합적 관리, 변수설정, 분석결과의 시각화, 데이터마이닝을 통한 심층 분석, 사용자 중심 분석결과의 연관성 강화의 5가지 컨셉으로 제시되었으며, 프로젝트 관리, 분석프레임 설정, 데이터 입출력, 기초 분석, 심층분석의 5가지 모듈로서 개발되었다. 제안된 도구는 모바일 폰의 사례조사를 통하여 그 효용성을 알아보았으며, 도구 활용의 사용성과 형태분석의 타당성이 검증되었다.