• Title/Summary/Keyword: Computer Simulation Program

Search Result 962, Processing Time 0.03 seconds

The Strength Analysis of Passenger Car Seat Frame (승용차 시트프레임의 강도해석)

  • 임종명;장인식
    • Transactions of the Korean Society of Automotive Engineers
    • /
    • v.11 no.6
    • /
    • pp.205-212
    • /
    • 2003
  • This paper may provide a basic design data for the safer car seat mechanism and the quality of the material used by finding out the passenger's dynamic behavior when protected by seat belt during collision. A computer simulation with finite element method is used to accomplish this objective. At first, a detailed geometric model of the seat is constructed using CAD program. The formation of a finite element from a geometric data of the seat is carried out using Hyper-Mesh that is the commercial software for mesh generation and post processing. In addition to seat modeling, the finite element model of seat belt and dummy is formed using the same software. Rear impact analysis is accomplished using Pam-Crash with crash pulse. The part of the recliner and right frame is under big stress in rear crash analysis because the acceleration force is exerted on the back of the seat by dummy. The stress condition of the part of the bracket is checked as well because it is considered as an important variable on the seat design. Front impact model which including dummy and seal belt is analyzed. A Part of anchor buckle of seat frame has high stress distribution because of retraction force due to forward motion of dummy at the moment of collision. On the basis of the analysis result, remodeling and reanalysis works had been repeatedly done until a satisfactory result is obtained.

Dynamic Analysis of Boom Using Finite Element Method (유한 요소법을 이용한 붐대의 동특성 해석)

  • Han, Su-Hyun;Kim, Byung-Jin;Hong, Dong-Pyo;Tae, Sin-Ho
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
    • /
    • 2005.05a
    • /
    • pp.987-991
    • /
    • 2005
  • The Aerial platform Truck is widely used for work in high place with the aerial platform. The most important thing is that worker's safety and worker must be able to work with trustworthiness so it needs to be verified its stiffness, deflection of boom, and dynamic condition concerned with a rollover accident. It should have an analytical exactitude because it is directly linked with the worker safety. In this point, we are trying to develop a proper CAE analysis model concerned with a rollover safety, bending stress and deflection for load. The Aerial platform Truck have a dynamic characteristics by load and moving of boom in the work field, so its static and dynamic strength analysis, structural mechanics are very important. Therefore, we evaluate the safety of each boom to calculating its stress, deflection. A computer simulation program is used widely for doing applying calculation of stiffness and structural mechanics, then finally trying to find a optimum design of the Aerial platform Truck.

  • PDF

Analysis and design of a FSK Demodulator with Digital Phase Locked Loop (디지털 위상고정루프를 이용한 ESK복조기의 설계 및 성능 분석)

  • 김성철;송인근
    • Journal of the Korea Institute of Information and Communication Engineering
    • /
    • v.7 no.2
    • /
    • pp.194-200
    • /
    • 2003
  • In this paper, FSK(Frequency Shift Keying) demodulator which is widely used for FH-SS system is designed and the experimental results are analyzed. The performance of the ADPLL(All-digital Phase-Locked-Loop), which is the main part of the demodulator circuit, is analyzed by the computer program. Using Maxplus-II tool provided by altera. co., ltd, each part of the ADPLL is designed and all of them is integrated into EPM7064SLC44-10 chip. And the simulation results are compared with the characteristics of the implemented circuits for analysis. There is about 2${\mu}\textrm{s}$ difference in time constant of the PLL. This difference is not critical in the demodulator. And the experimental results show that the transmitted data is well demodulated when the phase difference between the FSK modulated signal and the reference signal is about 180 degree.

Massless Links with External Forces and Bushing Effect for Multibody Dynamic Analysis

  • Sohn, Jeong-Hyun;Yoo, Wan-Suk;Hong, Keum-Shik;Kim, Kwang-Suk
    • Journal of Mechanical Science and Technology
    • /
    • v.16 no.6
    • /
    • pp.810-818
    • /
    • 2002
  • When the contribution of lightweight components to the total energy of a system is small, tole inertia effects are sometimes ignored by replacing them to massless links. For example, a revolute-spherical massless link generates two kinematic constraint equations between adjacent bodies and allows four relative degrees of freedom. In this paper, to implement a massless link systematically in a computer program using the velocity transformation technique, the velocity transformation matrix of massless links is derived and numerically implemented. The velocity transformation matrix for a revolute-spherical massless link and a revolute-universal massless link are appeared as a 6$\times$4 matrix and a 6$\times$3 matrix, respectively. A massless link model in a suspension composite joint transmitting external forces is also developed and the numerical efficiency of the proposed model is compared to a conventional multibody model. For a massless link transmitting external forces, forces acting on links are resolved and transmitted to the attached points with a quasi-static assumption. Numerical examples are presented to verify the formulation.

Crack constitutive model for the prediction of punching failure modes of fiber reinforced concrete laminar structures

  • Ventura-Gouveia, A.;Barros, Joaquim A.O.;Azevedo, Alvaro F.M.
    • Computers and Concrete
    • /
    • v.8 no.6
    • /
    • pp.735-755
    • /
    • 2011
  • The capability of a multi-directional fixed smeared crack constitutive model to simulate the flexural/punching failure modes of fiber reinforced concrete (FRC) laminar structures is discussed. The constitutive model is implemented in a computer program based on the finite element method, where the FRC laminar structures were simulated according to the Reissner-Mindlin shell theory. The shell is discretized into layers for the simulation of the membrane, bending and out-of-plane shear nonlinear behavior. A stress-strain softening diagram is proposed to reproduce, after crack initiation, the evolution of the normal crack component. The in-plane shear crack component is obtained using the concept of shear retention factor, defined by a crack-strain dependent law. To capture the punching failure mode, a softening diagram is proposed to simulate the decrease of the out-of-plane shear stress components with the increase of the corresponding shear strain components, after crack initiation. With this relatively simple approach, accurate predictions of the behavior of FRC structures failing in bending and in shear can be obtained. To assess the predictive performance of the model, a punching experimental test of a module of a façade panel fabricated with steel fiber reinforced self-compacting concrete is numerically simulated. The influence of some parameters defining the softening diagrams is discussed.

The Visual Evaluation of Face Image according to Color Coordination of Makeup (메이크업의 컬러코디네이션에 따른 얼굴이미지의 시각적 평가)

  • Jeong, Su-Jin;Kang, Kyung-Ja
    • Korean Journal of Human Ecology
    • /
    • v.15 no.4
    • /
    • pp.611-622
    • /
    • 2006
  • The purpose of this study is to investigate the effect of eyeshadow color (brown, purple, and blue), lipstick color (red, orange, and purple), and lipstick tone(vivid, light, dull, and dark) on the makeup image. The experimental materials used for this study were sets of stimulus and response scales (7 point semantic). The stimuli were 36 color pictures manipulated with the combination of eyeshadow color, lipstick color, and lipstick tone using computer simulation. The subjects were 216 female undergraduates living in Jinju city. The data was analyzed by using SPSS program. Analyzing methods were ANOVA and Duncan test. The result of this study are as follows. Image factor of the stimulus was composed of 4 different components (attractiveness and gracefulness, visibility, cuteness, and softness), Among them, the attractiveness and gracefulness and the visibility were important. Each dimensional image was affected by color coordination of eyeshadow color, lipstick color and lipstick tone. Therefore, the face image through matching eyeshadow and lipstick could be varied by the eyeshadow color, lipstick color and tones.

  • PDF

Numerical Study for the Design of Biogas-fired Low Emission Cyclone Incinerator (바이오 가스 소각용 저공해 사이클론 소각기 개발을 위한 수치 해석적 연구)

  • 전영남;김시욱;백원석
    • Journal of Korean Society for Atmospheric Environment
    • /
    • v.18 no.5
    • /
    • pp.401-410
    • /
    • 2002
  • Concerns for energy conservation, environmental pollution, and the fact that organic wastes account for a major portion of our waste materials, have created the interest of biogas, which usually contains about 60 to 70 percent methane, 30 to 40 percent carbon dioxide, and other gases, including ammonia, hydrogen sulfide, mercaptans and other noxious gases. Cyclone combustors are used for homing a wide range of fuels such as low calorific value gas, waste water, sludge. coal, etc. The 3-dimensional swirling flow, combustion and emission in a tangential inlet cyclone incinerator under different inlet conditions are simulated using a standard k-s turbulence model and ESCRS (Extended Simple Chemically-Reacting System) model. The commercial code Phoenics Ver.3.4 was used for the present work. The main parameters considered in this work are inlet velocity and air to fuel ratio. The results showed that the change of operating conditions had an influence on the shape and size of recirculation zones, mixture fraction and axial velocity which are important factors for combustion efficiency and emission behavior. The application of this kind of computer program seams to be promising as a potential tool for the optimum design of a cyclone combustor with low emission.

Daylighting Performance Nomographs for Toplit Atrium (아트리움의 자연채광 성능 예측용 노모그래프)

  • Kim, Jeong-Tai;Chung, Yu-Gun
    • KIEAE Journal
    • /
    • v.3 no.2
    • /
    • pp.45-50
    • /
    • 2003
  • Today, there are increasing evidences that daylight is essential for health, well-being and productivity. One of the strong contributions, which atria can make to advantages in building, is in allowing the use of daylight. This research is to develop nomographs and to evaluate the daylight performances of toplit atria with louvers. For this purpose, the evaluation models of toplit atria with well indexes of 0.5, 1.0 or 2.0 have been selected through the field surveys of atrium buildings in Seoul area. Also, weather data for solar irradiance and luminous efficacy were gathered from the recently conducted previous researches. The computer simulations were performed under clear sky conditions, using the ADELINE program, and various daylight performances were analyzed by the daylight illumination ratio. Analyzing the simulation results, solar altitude, solar azimuth, and louver angle and louver reflectance were found to be important factors affecting the daylight performance of toplit atria. Using these variables, regression equations have been formulated, and the nomographs, which may predict the daylight performances of toplit atria with louvers, were developed. The developed nomographs were validated through comparing the results of nomograph predictions to the results of scale-model experiments.

Decision Feedback Equalization Receiver for DS-CDMA with Turbo Coded Systems

  • Chompoo, T.;Benjangkaprasert, C.;Sangaroon, O.;Janchitrapongvej, K.
    • 제어로봇시스템학회:학술대회논문집
    • /
    • 2005.06a
    • /
    • pp.1132-1136
    • /
    • 2005
  • In this paper, adaptive equalizer receiver for a turbo code direct sequence code division multiple access (DSCDMA) by using least mean square (LMS) adaptive algorithm is presented. The proposed adaptive equalizer is using soft output of decision feedback adaptive equalizer (DFE) to examines the output of the equalizer and the Log- maximum a posteriori (Log-MAP) algorithm for the turbo decoding process of the system. The objective of the proposed equalizer is to minimize the bit error rate (BER) of the data due to the disturbances of noise and intersymbol interference (ISI)phenomenon on the channel of the DS-CDMA digital communication system. The computer program simulation results shown that the proposed soft output decision feedback adaptive equalizer provides a good BER than the others one such as conventional adaptive equalizer, infinite impulse response adaptive equalizer.

  • PDF

Design of a Dingle-chip Multiprocessor with On-chip Learning for Large Scale Neural Network Simulation (대규모 신경망 시뮬레이션을 위한 칩상 학습가능한 단일칩 다중 프로세서의 구현)

  • 김종문;송윤선;김명원
    • Journal of the Korean Institute of Telematics and Electronics B
    • /
    • v.33B no.2
    • /
    • pp.149-158
    • /
    • 1996
  • In this paper we describe designing and implementing a digital neural chip and a parallel neural machine for simulating large scale neural netsorks. The chip is a single-chip multiprocessor which has four digiral neural processors (DNP-II) of the same architecture. Each DNP-II has program memory and data memory, and the chip operates in MIMD (multi-instruction, multi-data) parallel processor. The DNP-II has the instruction set tailored to neural computation. Which can be sed to effectively simulate various neural network models including on-chip learning. The DNP-II facilitates four-way data-driven communication supporting the extensibility of parallel systems. The parallel neural machine consists of a host computer, processor boards, a buffer board and an interface board. Each processor board consists of 8*8 array of DNP-II(equivalently 2*2 neural chips). Each processor board acn be built including linear array, 2-D mesh and 2-D torus. This flexibility supports efficiency of mapping from neural network models into parallel strucgure. The neural system accomplishes the performance of maximum 40 GCPS(giga connection per second) with 16 processor boards.

  • PDF