• 한국운동역학회지
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• 제13권1호
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• pp.1-12
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• 2003

The purpose of this study was to design the method of 3D space calibration to reduce RMSE by statistical analysis when using the DLT algorithm and control frame. Control frame for 3D space calibration was consist of $1{\times}3{\times}2m$ and 162 contort points adhere to it. For calculate of 3D coordination used two methods about 2D coordination on image frame, 2D coordinate on each image frame and mean coordination. The methods of statistical analysis used one-way ANOVA and T-test. Significant level was ${\alpha}=.05$. The compose of methods for reduce RMSE were as follow. 1. Use the control frame composed of 24-44 control points arranged equally. 2. When photographing, locate control frame to center of image plane(image frame) o. use the lens of a few distortion. 3. When calculate of 3D coordination, use mean of 2D coordinate obtainable from all image frames.

• 건축사
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• 3호통권74호
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• pp.36-39
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• 1975

• 대한기계학회:학술대회논문집
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• 대한기계학회 2008년도 추계학술대회A
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• pp.378-383
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• 2008

Bogie frame of the locomotive is an important structural member for the support of vehicle loading. A lot of study has been carried out for the prediction of the structural integrity of the bogie frame in experimental and theoretical domains. The objective of this paper is to estimate the structural integrity of the bogie frame. Strength analysis has been performed by finite element analysis. From these analysis, stress concentration areas were investigated. For evaluation of the loading conditions, dynamic stress were measured by using strain gage. It has been found that the stress and strain due to the applied loads were multi-axial condition according to the location of strain gage. The fatigue strength evaluations of the bogie frame are performed to investigate the effect of the multi-axial load through the employment of the critical plane approach.

• Earthquakes and Structures
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• 제19권4호
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• pp.227-241
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• 2020

An experimental study has been carried out to investigate the effect of beam to column connection rigidity on the behavior of infilled steel frames. Five half scale, single-story and single-bay specimens, including four infilled frames, as well as, one bare frame, were tested under in-plane lateral cyclic reversal loading. The connections of beam to column for bare frame as well as two infill specimens were rigid, whereas those of others were pinned. For each frame type, two different infill panels were considered: (1) masonry infill, (2) masonry infill strengthened with shotcrete. The experimental results show that the infilled frames with pinned connections have less stiffness, strength and potential of energy dissipation compared to those with rigid connections. Furthermore, the validity of analytical methods proposed in the literature was examined by comparing the experimental data with analytical ones. It is shown that the analytical methods overestimate the stiffness of infilled frame with pinned connections; however, the strength estimation of both infilled frames with rigid and pinned connections is acceptable.

• 한국농공학회논문집
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• 제54권4호
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• pp.39-46
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• 2012

The objectives of this study is intended to analyze stresses using the boundary element method and probability analysis for agricultural structure. Loads and material properties are an important factor when analyzing the structure. Until now, designing structure, loads and material properties are applied deterministic value. However, load and material properties involve uncertainties due to those change probabilistic and deterministic methods could not consider uncertainties. To solve these problems, the reliability analysis based on probability properties scheme was developed. Reliability analysis is easy to approach to analysis frame structure, however it has limitation when solving plane stress strain problems a kind of agricultural structures. The BEM (Boundary Element Method) is able to analysis plane strain problems by boundary conditions. Thus, this study applied boundary element method to analysis plane strain problem, load and material properties as a probabilistic value to calculate the analytical model using Monte Carlo simulations were developed.

• 국제초고층학회논문집
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• 제3권3호
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• pp.185-190
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• 2014

Based on a 405m high super-tall building, the influence of outriggers, different shapes and layouts of structural plane and elevation on structural efficiency under lateral forces is studied in this paper. A calculation formula concerning the structural efficiency is given. The study shows that structural efficiency can be improved by triangulating the plane shape, using mega columns, the peripherization of the plane layout, tapering the elevation shape and setting bracing structure in the elevation. The arrangement of outriggers between the core tube and flange frame can reduce the shear lag effect in order to improve structural efficiency. The essence of improving structural efficiency of super-tall buildings is to maximize the plane bending stiffness and to make its deformation approach to plane section assumption.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 1996년도 한국자동제어학술회의논문집(국내학술편); 포항공과대학교, 포항; 24-26 Oct. 1996
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• pp.1308-1311
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• 1996

We propose a new linearized model which can be used very efficiently for the design and analysis of the autopilot of aerodynamically controlled skid-to-turn missiles. Proposed model is based on the linearized equations of the missile dynamics derived in the aerodynamic frame where xz plane contains the missile longitudinal axis and velocity vector. However, to take the effect due to the small perturbation of the missile body into consideration, we introduce a new frame which is identical to the aerodynamic frame in the trim state but after small perturbation it moves fixed with the missile body, and finally, the proposed model is set up in this frame. It is shown by nonlinear simulations and stability analysis of a numerical example that the new model describes the missile motion better than the conventional one linearized in the body frame with a certain amount of simplification.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 1999년도 봄 학술발표회 논문집(I)
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• pp.513-518
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• 1999

The objective of this experiment is to observe the elastic and inelastic behaviors of high-rise reinforced concrete frame with infilled masonry. To do this a building frame designed according to Korean seismic code and detailed in the Korean conventional manner was selected. An 1:12 scale plane masonry-infilled frame model was manufactured according to similitude law. Push-over test were performed under the roof displacement control. To simulate the earthquake effect, the lateral force distribution was maintained to be an inversed triangular by using whiffle tree. From the tests, story displacements, lateral story forces, local plastic rotations and the relations between inter-story drift versus story shear are obtained. Based on the test results, conclusions on the characteristics of the elastic and inelastic behaviors of a high-rise reinforced concrete frame with infilled masonry are drawn.

• 소음진동
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• 제9권5호
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• pp.966-974
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• 1999

This paper introduces modeling and its modal analysis procedure for exact and closed form solution of in-plane vibrations of general Timoshenko frame structures using exact dynamic element method(EDEM). The derivation procedure of the exact system dynamic matrices for Timoshenko beam frames is described. A new modal analysis procedure is also proposed since the conventional modal analysis schemes are not adequate for the proposed, exact system dynamic matrix. The proposed method provides exact modal parameters as well as all kinds of closed form solutions for general frame structures. Two numerical examples are presented for validating and illustrating the proposed method. The numerical study proves that the proposed method is useful for dynamic analysis of frame structures.

• Structural Engineering and Mechanics
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• 제74권1호
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• pp.121-128
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• 2020

This paper presents an experimental study on the dynamic characteristics of infilled reinforced concrete (RC) frames. A 1/3-scaled, one-bay, three-storey RC frame was produced and tested by using operational modal analysis (OMA). The experiments were performed on five specimens: one reference frame with no infill walls and four frames with infill walls. The RC frame systems included infill walls made of hollow clay brick, which were constructed in four different patterns. The dynamic characteristics of the patterns, including the frequency, mode shapes and damping ratios in the in-plane direction, were obtained by 6 accelerometers. Twenty-minute records under ambient vibration were collected for each model, and the dynamic characteristics were determined using the ambient vibration testing and modal identification software (ARTeMIS). The experimental studies showed that the infill walls significantly affected the frequency value, rigidity and damping ratio of the RC frame system.