• Title/Summary/Keyword: structure sensitivity study

Search Result 678, Processing Time 0.027 seconds

A Study on the Quality Deviation of Passenger Cars using the Robust Design (강건 설계 기법을 이용한 승용차의 품질 산포에 관한 연구)

  • Kim, Ki-Chang;Kim, Chan-Mook
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
    • /
    • 2006.05a
    • /
    • pp.110-113
    • /
    • 2006
  • This paper describes the development process of body and full vehicle for reduced idle vibration through the data level of frequency and sensitivity. The vibration mode map is used to separate body structure modes from resonance of engine idle nm and steering system. This paper describes the analysis approach process to reduce the variation of uncertainties for idle vibration performance at initial design stage. The robust design method is performed to increase the stabilization performance under vehicle vibration. It is used to predict the effects of the stiffness deviation according to the spot welding condition of the body structure. The tolerance associated with hood over slam bumper is analyzed for the quality deviation of the moving system in full vehicle. And the glass sealant stiffness and weight difference is considered for the deviation characteristic. The design guideline is suggested considering sensitivity about body and full vehicle by using mother car at initial design stage. It makes possible to design the good NVH performance and save vehicles to be used in tests. These improvements can lead to shortening the time needed to develop better vehicles.

  • PDF

Sensitivity Analysis Related to Redundancy of Regular and Irregular Framed Structures after Member Disappearance

  • Ito, Takumi;Takemura, Toshinobu
    • International Journal of High-Rise Buildings
    • /
    • v.3 no.4
    • /
    • pp.297-304
    • /
    • 2014
  • Recently, there have been some reported examples of structural collapse due to gravity, subsequent to damage from accident or an excitation that was not prepared for in the design process. A close view of new concepts, such as a redundancy and key elements, has been taken with the aim of ensuring the robustness of a structure, even in the event of an unexpected disturbance. The author previously proposed a sensitivity index of the vertical load carrying capacity to member disappearance for framed structures. The index is defined as the ratio of the load carrying capacity after a member or a set of an adjacent member disappears, to the original load carrying capacity. The member with the highest index may be regarded as a key element. The concept of bio-mimicry is being applied to various fields of engineering, and tree-shaped structures are sometimes used for the design of building structures. In this study a sensitivity analysis is applied to the irregular-framed structures such as tree-shaped structures.

A Study on current sensor (전류 검출기에 대한 연구)

  • Lee, Hwan
    • The Transactions of the Korean Institute of Electrical Engineers
    • /
    • v.45 no.3
    • /
    • pp.335-340
    • /
    • 1996
  • The item and structure of current detector depends on the current in conductors. The Hall current detector of these detectors is to use the variation of Hall voltage to conductor's current and it is very difficult for the conventional type to detect small current. In this paper we study experimented-method that detect AC current by using the magnetic modulation method the current, 0[mA]~100[mA]. The experiments results in 5 percent against the conventional, 20 percent in linear error, 0.12[.DELTA.mV/.DELTA.mA] to conventional type, 50[.DELTA.mV/.DELTA.mA] in sensitivity. (author). 7 refs., 15 figs.

  • PDF

Sensitivity of Track Components on the Linear Thermal Buckling (선형온도좌굴에 대한 궤도 구성요소의 민감도)

  • 임남형;강영종;성익현
    • Proceedings of the KSR Conference
    • /
    • 2002.05a
    • /
    • pp.207-212
    • /
    • 2002
  • The actual buckling of the railroad track structure is suspected to be a complex interaction between the vertical, lateral and torsional modes. To make the analysis tractable, however, most studies restrict themselves to either the vertical or the horizontal plane. Based on a comprehensive and realistic three-dimensional track model developed in the previous study, three dimensional buckling analysis of CWR track subjected to temperature load was performed. Using the study on buckling temperature and mode, sensitivity of track components such as tie spacing, ballast resistance, stiffness of pad-fastening system and rail size were investigated.

  • PDF

MANAGEMENT DECISION-MAKING FOR SUGARCANE FERTILIZER MIX PROBLEMS THROUGH GOAL PROGRAMMING

  • Sharma, Dinesh K.;Ghosh, Debasis;Alade, Julius A.
    • Journal of applied mathematics & informatics
    • /
    • v.13 no.1_2
    • /
    • pp.323-334
    • /
    • 2003
  • This paper presents a goal-programming (GP) model for management decision-making for sugarcane fertilizer mix problems. Sensitivity analysis on the priority structure of the goals has been performed to obtain all possible solutions. The study uses Euclidean distance function to measure distances of all possible solutions from the ideal solution. The optimum solution is determined from the minimum distance between the ideal solution and other possible solutions of the problem. The optimum solution corresponds to the appropriate priority structure of the problem in the decision-making context. furthermore, the results obtained from sensitivity analysis on the cost of combination of fertilizers confirm the priority structure.

Design Automatization of Space Truss Structure Using Optimizations Technique (최적화 기법을 이용한 3차원 트러스 구조물의 설계자동화)

  • 최은규;임기식;이병해
    • Proceedings of the Computational Structural Engineering Institute Conference
    • /
    • 1993.10a
    • /
    • pp.81-90
    • /
    • 1993
  • The optimum design of a structure requires the determination of the economical member size and shape of the structure which satisfies the design condition and function. In this study, the process of design automatization of three-dimensional truss structure introduces the optimization technique tests its application in the design automatization, proposes its application method and applies the example structure of the parabolic antenna truss. Using the Formex Algebra of configuration function, the structure's mesh-generation is automatized. By using the program developed in this study, the input member array, member size and load condition designer can generate the input data file for the structure analysis and optimum design. This study is aimed at the development of a design automatization system that search for tile optimum value of a structure design by observing the structure's sensitivity from the modification of member array and member property.

  • PDF

Capital Structure and Financial Performance: A Case of Saudi Petrochemical Industry

  • ALI, Anis;FAISAL, Shaha
    • The Journal of Asian Finance, Economics and Business
    • /
    • v.7 no.7
    • /
    • pp.105-112
    • /
    • 2020
  • The study investigates and measures the impact of capital structure, profitability and financial performance on the success of the business organization. Capital structure of the business organization refers to the proportion of external funds and internal funds, i.e., debt and equity. In Saudi Arabia, petrochemicals companies are working on equity, but financial performance reflects negative trend for the period 2004 to 2016. The research is based upon secondary data available on the websites of petrochemicals companies of Saudi Arabia. Financial Ratio variability analysis and Trend Indices of financial ratios (TICBI) measure and compare the financial variability and sensitivity of financial ratios of the business organization. Correlation between Trend Indices (TICBI) of independent variable and dependent variables are to be calculated to know the impact of changes in debt equity on other dependent variables. The results reveal the unexpected performance of petrochemicals companies due to under-utilization of the resources caused by low demand and lower prices of the products governed by some internal and external factors. The study finds that size, demand, cost of production, profitable streams of products, and low cost capital in external funds are the factors responsible for overall growth development of the petrochemicals industry of Saudi Arabia.

A study on Quadrature error Reduction of Design Methodology in a Single Drive 3-Axis MEMS Gyroscope (단일 구동 3축 MEMS자이로스코프의 구적 오차 저감을 위한 설계 기법에 관한 연구)

  • Park, Ji Won;Din, Hussamud;Lee, Byeung Leul
    • Journal of the Semiconductor & Display Technology
    • /
    • v.21 no.4
    • /
    • pp.132-137
    • /
    • 2022
  • In this paper, we have studied the quadrature error reduction for the single drive 3-axis MEMS Gyroscope. There was a limitation of the previous study which is the z-axis quadrature error was large. To reduce this value, design methodologies were presented. And the methodologies included a different mesh application, z-rate spring structure change, and mass compensation for balancing of the structure. We conducted the modal analysis, drive mode analysis and sense mode analysis using COMSOL Multiphysics. As a result, a drive resonant frequency was 26003 Hz, with the x-sense, y-sense, z-sense being 26749 Hz, 26858 Hz, 26920 Hz, respectively. And the Mechanical sensitivity was computed at 2000 degrees per second(dps) input angular rate while the sensitivity for roll, pitch, and yaw was computed 0.011, 0.012, and 0.011 nm/dps respectively. And z-axis quadrature error was successfully improved, 2.78 nm to 0.95 nm, which the improvement rate was about 66 %.

An Study of Optimization on Vehicle Body Stiffness using CAE Application (CAE를 응용한 차체강성 최적화에 관한 연구)

  • 최명진;송명준;장승호
    • Transactions of the Korean Society of Automotive Engineers
    • /
    • v.9 no.6
    • /
    • pp.129-134
    • /
    • 2001
  • One of the most important purposes in the design of machines and structures is to produce the most light products of the lowest price with satisfying function and performance. In this study, a scheme of design optimization for the weight down of vehicle body structure is presented. Design sensitivity of vehicle body structure is investigated and design optimization is performed to get weight down with the allowable stiffness of body in white. Stress, deformation and natural frequencies are the constraint of the optimization.

  • PDF

Sensitivity Analysis on the Lateral Behavior of Diagrid Structure (다이아그리드 구조 시스템의 횡적 거동에 대한 민감도 해석)

  • Ahn, Keun-Woo;Yang, Jae-Kwang;Park, Sung-Soo
    • Journal of the Korea institute for structural maintenance and inspection
    • /
    • v.19 no.3
    • /
    • pp.73-82
    • /
    • 2015
  • In evaluating lateral behavior on the seismic and wind load, the purpose of sensitivity analysis is to find critical variables and to identify characteristic response with variability of variables. The sensitivity analysis is very important in structural diagnosis, repair and reinforcement field. This study investigates the sensitivity by linear static analysis applying the TDA method in changing angles of diagrid braces on the same height structures. In case of mid rise model, under the seismic load, the brace member is determined as a major variable at $58^{\circ}$ but a high rise model, under the wind load, has the brace member as a major variable at $67.4^{\circ}$. In addition, location of critical sensitivity on the mid rise model is distributed over middle section, while it is distributed lower section on the high rise model.