Vibration reduction on city buses: Determination of optimal position of engine mounts

2010 ◽  
Vol 24 (7) ◽  
pp. 2198-2209 ◽  
Author(s):  
Ali El Hafidi ◽  
Bruno Martin ◽  
Alexandre Loredo ◽  
Eric Jego
Keyword(s):  
Vibration Reduction ◽  
Optimal Position ◽  
Engine Mounts

The Determination of the Three-Point Support Design of Machine Tool Based on iSIGHT

2014 ◽  
Vol 607 ◽  
pp. 342-345
Author(s):  
Sheng Hui Zhao ◽  
Xiao Chuang Zhu ◽  
Da Wei Zhang
Keyword(s):  
Machine Tool ◽  
High Precision ◽  
Multidisciplinary Optimization ◽  
Joint Surface ◽  
Objective Functions ◽  
Multi Objective Optimization ◽  
Support Design ◽  
Optimal Position ◽  
Point Support

In order to meet the requirements of high-precision machine tool, it has been an important factor to select an appropriate way to support the bed. By building a multidisciplinary optimization (MDO) process based on iSIGHT, this article select the deformation difference of the guides and the deformation difference of the joint surface between column and bed of the machine tool as the objective functions, and then conduct a multi-objective optimization (MOO) of the positional parameters of the three-point support. Eventually the optimization result is given and the optimal position of the three-point support is determined.

Determination of optimal parameters of the tuned mass damper to reduce the torsional vibration of the shaft by using the principle of minimum kinetic energy

2018 ◽  
Vol 233 (2) ◽  
pp. 327-335 ◽  
Author(s):  
Duy-Chinh Nguyen
Keyword(s):  
Kinetic Energy ◽  
Torsional Vibration ◽  
Damping Ratio ◽  
Vibration Reduction ◽  
Tuned Mass Damper ◽  
Optimal Parameters ◽  
Lagrangian Equations ◽  
Tuning Ratio ◽  
Mass Damper

In this paper, an analytical method is presented to determine the optimal parameters of the symmetric tuned mass damper, such as the ratio between natural frequency of tuned mass damper and shaft (tuning ratio) and the ratio of the viscous coefficient of tuned mass damper (damping ratio). The optimal parameters of tuned mass damper are applied to reduce the torsional vibration of the shaft based on consideration of the vibration duration and stability criterion. The dynamic equations of the shaft are provided via Lagrangian equations, and the optimal parameters of tuned mass damper are derived by using the principle of minimum kinetic energy. Analytical and numerical examples are implemented to verify the reliability of the proposed method. The analytical and numerical results indicate that the optimal parameters of tuned mass damper have significant effects in the torsional vibration reduction of the shaft.

scholarly journals OPTIMIZATION OF THE SOLAR COLLECTOR’S POSITION

2017 ◽  
Vol 7 (2) ◽  
pp. 12-14
Author(s):  
Bogdan Sydorchuk ◽  
Oleksandr Naumchuk ◽  
Paweł Mazurek
Keyword(s):  
Solar Energy ◽  
Computer Model ◽  
Solar Collector ◽  
Mathematic Model ◽  
Optimal Position ◽  
Optimal Values

: It is made the mathematic model of determining of the solar collector’s parameters, that allows to get its optimal values for any latitude at an any point of time. Also it is developed the computer model for determination of the daily influx of solar energy on the surface of the solar collector, which allows to determine its optimal position.

Analysis of functional methods for determining the optimal position of the mandible

2020 ◽  
Vol 25 (1) ◽  
pp. 22-25
Author(s):  
L. V. Dubova ◽  
S. S. Prisyazhnykh ◽  
N. V. Romankova ◽  
D. V. Malahov
Keyword(s):  
Temporomandibular Disorders ◽  
Load Test ◽  
Diagnostic Methods ◽  
Graphic Method ◽  
Optimal Position ◽  
Advantages And Disadvantages ◽  
Functional Methods ◽  
The Subject ◽  
Physiological Method

Relevance. The subject of the research is to compare different functional methods for determining the optimal position of the mandible.Purpose. To find the advantages and disadvantages of using various functional diagnostic methods to determine the optimal position of the mandible.Materials and methods. We conducted a literature review of the functional methods for determining the optimal position of the mandible in the treatment of patients with temporomandibular disorders. Nowadays different methods are used, such as anatomical and physiological method, bilateral manipulation, front deprogrammer, graphic method, aksiography, kineziography, TENS et al.Results. The method of bimanual manipulation and frontal deprogrammer determine the central relation when TMJ pathology is not expressed and the load test is negative. The graphic method evaluates the function of the temporomandibular joint, determines the optimal position of the mandible. TENS moves the lower jaw to a position of physiological rest. Kinesiography and Axiography determine the temporomandibular disorders and we can use them to dynamically monitor patients at all stages of treatment, monitor the determination of the optimal position of the mandible.Conclusion. From the results of this study, we can conclude that there are a lot of methods of functional diagnostics of TMJ, which help to determine the optimal position of the mandible. Everybody can choose their own set of methods, that let reduce the number of non-examined patients with temporomandibular disorders.

Modeling and Implementation of Semi-Active Hydraulic Engine Mounts

1988 ◽  
Vol 110 (4) ◽  
pp. 422-429 ◽  
Author(s):  
P. L. Graf ◽  
R. Shoureshi
Keyword(s):  
Experimental Data ◽  
Experimental Study ◽  
Low Power ◽  
Dynamic Model ◽  
Automotive Industry ◽  
Vibration Reduction ◽  
New Approach ◽  
Active Mode ◽  
Engine Mounts ◽  
Impedance Characteristics

In an effort to improve passenger comfort, the automotive industry is evaluating more sophisticated techniques to reduce engine excited frame vibrations. A new approach is to implement hydraulic mounts in a semi-active mode. In this mode, low power actuators are used to change the impedance characteristics of the mount. This paper presents a dynamic model and analysis of the semi-active hydraulic mount. Experimental data confirming the mount model are presented. Finally, results of an experimental study on the implementation of the semi-active mounts on a production automotive vehicle are presented. The study focuses on frame vibration reduction during engine idle. The semi-active hydraulic mounts show improved vibration levels over passive hydraulic mounts in the vehicle application.

Enhancement of the Catalytic Performances in the Case of a Consecutive-Parallel Reaction Scheme

2010 ◽  
Vol 8 (1) ◽  
Author(s):  
Yacine Benguerba ◽  
Brahim Djellouli
Keyword(s):  
Considerable Increase ◽  
Reaction Scheme ◽  
Element Distribution ◽  
Parallel Reaction ◽  
Bulk Fluid ◽  
Optimal Position ◽  
Dirac Function ◽  
Specific Distance ◽  
Catalytic Performances

The determination of the optimal distribution of the catalytic activity profile, which maximizes the catalytic effectiveness and the selectivity, in created unsteady state conditions, is analyzed and treated numerically for the case of a consecutive-parallel reaction scheme. The optimal active element distribution is always a Dirac-? function, i.e., all the catalyst is deposited at a specific distance from the center of the catalytic pellet. The main result is that the location of this optimal position varies with time and that the modulation, of the temperature and the reactants concentrations of the external bulk fluid, leads to a considerable increase of the catalytic effectiveness. On the other hand the selectivity was found to be not affected by the modulation except for higher values of ?2 (?2>0.3).

Determination of optimal position for both support bearing and unbalance mass of balance shaft

2012 ◽  
Vol 50 ◽  
pp. 150-158 ◽  
Author(s):  
Chan-Jung Kim ◽  
Yeon June Kang ◽  
Bong-Hyun Lee ◽  
Hyeong-Joon Ahn
Keyword(s):  
Optimal Position ◽  
Balance Shaft

scholarly journals Detector Dead Time Determination and Optimal Counting Rate for a Detector Near a Spallation Source or a Subcritical Multiplying System

2012 ◽  
Vol 2012 ◽  
pp. 1-7 ◽  
Author(s):  
V. Bécares ◽  
J. Blázquez
Keyword(s):  
Counting Rate ◽  
Dead Time ◽  
Simple Expression ◽  
Optimal Position ◽  
Spallation Source ◽  
Time Determination ◽  
Accelerator Driven Systems ◽  
Counting Statistics ◽  
The One

The operation of accelerator-driven systems or spallation sources requires the monitoring of intense neutron fluxes, which may be billions-fold more intense than the fluxes obtained with usual radioactive sources. If a neutron detector is placed near a very intense source, it can become saturated because of detector dead time. On the contrary, if it is placed far away from the source, it will lose counting statistics. For this reason, there must exist an optimal position for placing the detector. The optimal position is defined as the one with the minimal relative uncertainty in the counting rate. In this work, we review the techniques to determine the detector dead time that can be applied with an accelerator-driven subcritical system or a spallation source. For the case of a spallation source, counting rates do not follow Poisson's statistics because of the multiplicity of the number of neutrons emitted by incident proton. It has been found a simple expression that relates the optimal counting rate with the source multiplicity and the uncertainty in the determination of the dead time.

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