In this paper, a composite material analysis program based on the finite element method(FEM) is used. The purpose of this study was to verify whether the composite material analysis program which developed as part of a project of development of softwares and educational contents for structural vibration and composite material analysis that can calculate how similar the macroscopic mechanical behavior of the composite materials actually. Because composite materials are generally anisotropic, analysis of composite laminate is used for the constitutive equations of orthotropic material. For convenience, the unit is ommited in all calculations. To verify the accuracy of the finite element method based program, the deflection and stress distribution of the simply supported composited material laminated plate subjected to a uniform load distribution is compared with exact solution. Size and properties of the composite material laminate used for analysis are fixed variables, and by changing the number of elements and the total thickness of the laminate is compared with the exact solution to the resulting value, respectively.

본 논문은 하중에 따른 변화정도에 초점을 맞추어 PSC girder길이의 증가를 위해 Co-rotational Plane Beam with Arbitrary Section Solver를 통하여 비선형 구조해석을 진행하여 Jeon, S, Choi, M, and Kim, Y. 등에 의해 제시된 Decked girder의 구조적 우수성을 검증하고, 이를 보완한 새로운 단면형상의 PSG girder를 제시하였다. 도출된 결과 값은 탄성방정식을 통하여 얻은 값과 비교하여 신뢰성을 검증하였다. 해석을 통하여 단순히 girder 상단부 플랜지의 길이를 증가시키는 것은 girder의 변형정도를 줄이는데 큰 영향을 주지 않는 다는 사실을 알 수 있었고 girder 상단부 플랜지와 중심부를 연결하는 부분의 단면형상을 좀 더 두껍게 함으로 하중에 따른 girder의 변형량을 크게 감소시킬 수 있었다.

There are different kinds of aircrafts, such as conventional airplane, rotorcraft, fighter, and umanned aerial vehicle. Their shape and feature are dependent upon their assigned mission. One of the fundamental analyses during the design of the aircraft is the structural analysis. The structural analysis becomes more complicated and needs more computations because of the on going complex aircrafts' structure. In order for efficency in the structural analysis, a simplified approach, such as equivalent beam or plate model, is preferred . However, it is not clear which analysis will be appropriate to analyze the realistic configuration, i.e, an equivalent beam or plate analysis for an aircraft wing. It is necessary to assess the boundary between the one dimensional beam analysis and the two dimensional plate theory for an accurate structural analysis. Thus, in this paper, the static structural analysis results obtained by EDISON solvers were compared with the three dimesional results obtained from MSC NASTRAN. Before that, EDISON program was verfied by comparing the results with those from MSC NASTRAN program and analytic solution.

처음 에디슨 경진대회를 준비할 때 업로드 되어 있는 다양한 프로그램을 보면서 어떤 주제를 선정할 지 고민을 하던중, 눈에 들어온 프로그램은 서울대학교에서 제작한 Co-rotational Plane beam-Dynamic tip load이란 프로그램이었다. 위 프로그램은 한쪽 단이 고정된 외팔보(cantilever beam)의 끝단에 하중을 시간에 관련된 함수(sin, cos)로 주어 각 절점에서의 변위(X, Y), 속도 그리고 가속도를 알려주는 프로그램이다. 우리는 이 프로그램을 이용해서 외팔보 끝단의 진동 형태와 주기가 어떤 요인(단면의 모양, 재료의 성질, 가하는 하중의 진동수 등)에 의해서 변하는지 분석할 수 있었다. 거기서 더 나아가 하중을 실제 지진상황에서의 크기와 유사하게 주고 위 프로그램에서의 보의 거동(진동 주기, 진동 변위 등)을 건물의 거동이라 가정했을 때 면진 주기를 얼마로 설정해야하는지도 알 수 있었다.

In this paper, we write about EDISON program. We study about where to use this program. We can use this program for FEA naturally. But we study that using this program in class. Many students can't understand many machanics of materials' problem. They want to see image such as change of beam. It can help students to understand many problem. We can use ANSYS or Abaqus. But EDISON program is better for students because of it is freeware. In this paper, I write two problem. One is peak stress of basic beam, another is shearing stress flow of I-beam. On the basis of this, EDISON program will be widely used.

In this paper, a coil spring of the suspension components of the car is calculated through. FEM(Finite Element Method) when a portion of the one is applied by an external load. We analyze the situation by using 'Large Deformation Analysis SW'in the EDISON structural dynamics server. Results of the analysis are about a displacement of the upper spring after defomation and total mass, and we use them to calculate the spring constant and maximum von-Mises stress by using Hooke's law and von-Mises stress eqution. Finally, we visualize the relationship between the calculated spring constant and the mass through graphs and this data are beneficial for industries related to the spring.

In this paper, the cross section properties of thin walled beam are calculated through KSec2D in consist of Saint Venant theory. To investigate tendency increasing the thickness, we analysis cross section using istopic material. In the asymmetric cross section, We investigate effect caused cross section properties accompanied increasing the thickness. The structural properties such as bending stiffeness, tosion stiffness per area of each cross section in three cases is compared through increasing thickness. The warping displacement calculated by KSed2D is modeled by CATIA. In order to show that warping influence the cross section, the warping shape modeled CATIA is printed 3D printer.

In this paper, an systematic approach is presented, in which the bridge type traffic sign structure is body out by CSDDA prepost processor. There is dead load and wind load that is working on the structure which will make force and moment. Analyzied the stress distribution of the standard form and by changing the shape, compared th safety in terms of defelction and stress (with the standard form) to know the effect of each component in the bridge type traffic sign structure. The safety of deflection and stress is evaluated by maximum distance/1000 and ASIC code respectively. The standard form of bridge type traffic sign structure is established by two pairs of pillar and two pairs of floor beam. Replaced the links which is consist of flange and screws as the torsion spring and run our analysis program. By adjusting variable of rigidity modulus of torsion sprign, moment between column and beam is controled depending on value of rigidity modulus.

In this paper, Timoshenko and Euler-Bernoulli beam theories (EB-beam)are used, and Fast Fourier Transformation(FFT) analysis is then employed to extract their natural frequencies using both analytical approach and co-rotational plane beam(CR-beam) EDISON program. EB-beam is used to analyze a spring mass system with a single degree of freedom. Sinusoidal force with various frequencies and constant magnitude are applied to tip of each beam. After the oscillatory tip response is observed in EB-beam, it decreases and finally converges to the so called 'steady state'. The decreasing rate of the tip deflection with respect to time is reduced when the forcing frequency is increased . Although the tip deflection is found to be independent of the excitation frequency, it turns out that time to reach the steady state response is dependent on the forcing frequency.

In this paper, to examine the difference between the linear and non linear static, dynamic analysis for a structure, a cantilevered beam was used. Then, an external transverse static and dynamic loads were applied at the free end of the beam. Classical theories were used for the linear analysis and the EDISON CSD solver, co-rotational dynamic FEM program, was used for nonlinear analysis. In the static analysis, effects of the load for the beam deflection were observed in the linear and nonlinear analysis. Then, normalized displacement of tip of the beam was predicted for different frequency ration and a significant difference was obtatined in the vicinity of the resonant frequency. In addition, effects of frequency and time for the beam deflection were investigated to find the frequency delay.

When we use a Finite Elements Method(FEM) to solve a linear static analysis problem, number of elements need to be sufficiently small for convergence of the solution. If we analysis a part, whose curvature is varying heavily, we face to determine how small the elements size is, because the calculated stress is increased as the elements are smaller. In this case, we need to analysis with mesh insensitive method, stress linearization. We can get a solution that is not varying with the elements size if the size is smaller than a certain level. In this paper, we evaluate a pressure vessel having geometrical discontinuities using stress linearization. First, we analysis the vessel with global model, including all part of the vessel, using large shell elements. Second, we analysis the local part of the vessel, which is the small part occurring maximum stress, using small continuum elements. Last, we evaluate the safety of the pressure vessel according to the ASME Sec. VIII Div 2.

복합재는 높은 비강도와 비강성을 가지고 있어 자동차, 항공기 등 전반적인 산업분야에서 널리 사용되는 재로이다. 우주선의 노즐 부분과 같이 높은 온도 뿐 아니라 높은 압력이 작용하는 환경에서 사용하기 위한 재료로 복합제가 필요하다. 복합재의 물성치를 아는 것은 매우 중요한데 모재(matrix)와 강화섬유(fiber) 각각의 물성치를 수치적으로 대입해 얻는 결과는 실험값과의 오차가 커 예측하는데 있어 더 정확한 방법이 필요할 것이다. 본 연구에서는 유한요소법을 이용한 EDISON용 CASADsolver 프로그램을 활용해 분석하였다. Matrix와 fiber의 물성치를 대입해 복합재의 물성치를 구해 실험으로 측정된 물성치, 경험식으로 계산된 물성치와 비교를 하였다.

In this paper, the study of the optimum design for a geometry of the handle bar to obtain a high stiffness and light weight is investigated, using EDISON simulation program. High stiffness and weight lightening are considered as the major performance indicators of the componet of the bicycle. Four design factors and three levels of the design factors are selected for the structural optimization and experiments are designed using the orthogonal array of L9 by Taguchi method. We calculated SN ratio of larger the better and smaller the better characteristics from FEA results and analysed the effects of design factors on characteristics. We choosed the optimum level of design factors based on deflection and safety factor. Comparing the results of FE analysis with converted value of predicted SN ration, we made sure for reliability of Taguchi method and FE method for structural optimization.

In this paper, a study was conductd for the optimization through shear web of shape the Edison program in wind power blade. We measured the displacement and stress distribution through two optimization methods to select the model with the smallest displacement and stress values Before running the analysis, We try to find the inflection point throught the shear web of the model and then analyze by introducing the geometric nonlinearity. The first optimization variables are introduced by the pitch angle and three web shapes. Third model such a honeycomb structure is good way to get an advantage for bending test. Acoording to a method of previous optimization, third model is chosen and then the thickness of the web and blade as a variable is introduced, it is extracted as a result of displacement and the maximum stress per mass.

Oseltamivir, also known as Tamiflu, is an inhibitior of neuraminidase protein which plays an essential role in proliferation and replication of influenza virus. Binding to the active site of neuraminidase, the oseltamivir prevents the protein frome enzyme reaction. Conformational change of the protein(neuraminidase) should be accompanied by the enzyme reaction, but the drug inhibitis the protein to deform. In this study, we examine the influence of oseltamivir on protein's conformational change in the structural and mechanical point of view. Finite element analysis of the protein can be an useful approach to investigae the influence of oseltamivir on the deformation loading condition based on the first more energy to change shape of the protein with an oseltamivir attached than the protein without an oseltamivir.

In this paper, 2 kinds of models about bike frame are simulated with static structural analysis. A bike frame with diamond type is compared with another model that Down tube is eliminated from original diamond frame. About both types of models, Property of a material and conditions of restriction & load are the same. This study shows reinforcement effects of a partial frame by adding down tube and impacts generated by applying a load at the frame such as weak points & high stress parts as well as expected deformation. The structural result of this study indicates that the equivalent stress or total deformation decreases by 57.1% or 36.4%, respectively. Also stress concentration sites are leg connecting parts, front/rear wheels fixed region and Max deformation is generated from Seat tube. In conclusion. A Down tube is highly efficient as rein forcemet thatn frame without non down tube. Furthermore, The safety rises in case of reduing top tube thickness and increasing a reinforcement at leg connecting parts or concentration regions.

이 논문에서는 역학적 지식과 EDISON 구조동역학 서버에서 지원하는 이공계 교육 및 연구용 시뮬레이션 프로그램 중 Co-rotational plane beam with arbitrary section을 이요아여 캔틸레버 보의 처짐을 기하 비선형적으로 해석한다. 또한 해석에 사용된 프로그램이 실제 교육에 적용이 가능한 지를 고찰한에 그 목적이 있다. 처짐을 해석하기 위하여 수계산, 프로그램을 이용하여 얻은 결과값을 비교하였고 캔틸레버 보의 변화 형상을 시각화 하였다.

푸아송비(poisson's ratio)는 종방향 변형률에 대한 횡방향 변형률의 비로, 우리 주위 대부분의 재료들은 양의 푸아송비를 지닌다. 그러나 재료가 특정한 격자구조를 이루도록 설계할 경우 구성물질이 양의 푸아송비를 가지더라도 거시적으로는 음의 푸아송비를 구현할 수 있으며, 이러한 극한물성물질(metamaterial)을 오그제틱 물질(auxetic material)이라고 부른다. 이전까지 오그제틱 물질을 구현하기 위한 오그제틱 구조를 빔 구조물로 모델링하여 유한요소해석을 수행하고 주요 설계 변수인 리엔트런트 각에 따라서 푸아송비와 유효 탄성계수가 어떻게 변화하는지 확인하였다.

해상 pedestal 크레인은 각종 운송물을 선박에 싣거나 내리는 해상 운송에 필수적인 장비이다. 따라서 구조적 안전성을 가지는 크레인 설계가 요구된다. 그의 일환을 수행된 '해상 pedestal 크레인의 설계 개선을 위한 연구'에서는 기존 크레인의 기초 설계에 대해서 구조적 안전성을 평가하여 개선 방안을 제시하였다. 또한 좌굴 안정성 향상을 위한 보강재 설계를 수행하였다. 하지만 상세설계 관점에서 미비한 점이 있어 이를 보완할 필요성이 있다. 안전성 평가를 위해 필요한 응력을 계산하기 위해 EDISON-CSD프로그램을 통해 유한요소모델 해석을 활용한 구조해석을 수행하였다. 효율적인 해석을 위해 상세설계에 필요한 부분영역을 선택하여 모델링 하였으며 전체영역에서의 해석 결과 값을 등가 힘, 등가 모멘트로 환산하여 경계조건으로 부여하였다. 보강재간의 교차점 형상이 안전성에 미치는 영향을 보기위해 stiffener와 diaphragm의 교차점 형상(반원, 정사각형, 사다리꼴)에 따라 안전성 평가를 수행하였고, 안전 여유의 유효한 차이를 보이지 않음을 확인하였다. 평가에 필요한 응력계산을 위해 또한 Diaphagm의 좌굴에 대한 영향을 고려하기 위해 설계 규격 DNV-RP-201 8장 (Buckling of girders)을 분석하였고, 안전성 평가에 반영하였다. 또한 실제 현장에서 보편적으로 사용되는 angle형상 stiffener의 치수 도출을 위해 최적설계를 수행하였고, 모든 설계 제한조건을 만족하면서 최소의 무게를 가지는 합리적인 치수를 도출하였다.

On wide variety of fileds, studies on active twist control are becoming more active, For effective twist control, blas have to have low tosional stresses with high torsional deformations to the same magnitude to the same magnitude of torque acting on its cross section. In this study, 2D sectional analysis and 3D finite element analysis were made for 5 different blades with each having different cross sections which have different spas, The results from 2D sectional analysis, were then put into 3D blade deformation and stress calculations which lead to analysis. Outcomes from 2D and 3D analysis, showed that on the same torque and concentrated load conditions, the blade with "C" shaped spar was the best of all the blades which were used in this study.