Papers by Keyword: Acceleration

Abstract: Currently, the community is an explosion of information society, how to quickly find the information which is our requirement has increasingly become the focus of attention in many fields. Image information is an intuitive means of expressing and describing the objective things. Fast query information by image uniqueness has become a hot topic of current research. In this paper, we introduce a method of using MPI parallel processing to accelerate SIFT image matching algorithm in order to achieve information query in museum exhibitions and other applications.

Abstract: The lexical meaning of derailment shall be the wheels of trains going off the track and it is an important factor for the running safety of railway vehicles. For the measurement of interaction forces between the wheel and the rail, wheel set is used with normal method and the vibration accelerometer is used with simplified method to assess the safety of a railway vehicle in the derailment process. The result has been recorded by measuring vibration acceleration.

Abstract: At a serious rail corrugation line along Beijing metro Yi-zhuang line, one experiment of controlling rail corrugation has done. Based on the test and analysis of rail vibration decay rate, rail surface roughness and vibration acceleration on the rail and track bed before and after install TRD, it is concluded that install TRD on rail waist could improve rail damping, enhance rail vibration decay rate, speed up vibration wave propagation decay in the rail, reduce the vertical vibration of rail and track bed, and control the development of rail corrugation.

Abstract: In order to diagnosis the fault in a a comprehensive, real-time and simple way, a multi-input predictive fault diagnosis system was promoted based on acceleration mainly include the sensor, Signal processing,display and stepper motors.Sensor was used to acquisition the inputs such as grain loss, clogging and engine vibration.Then,the inputs was processed by the fault diagnosis algorithm promoted in this thesis to obtain diagnostic results and display the rusults in button display module. When a fault occured, stepper motor would start to work controled by a control signal to minimized the failure harm.Furtherly,the effectiveness was improved by an example. The experimental results show that the prediction method can achieve the predictive fault diagnosis and effectively simplify the computational complexity with good practicality and reality.

Abstract: The highway roadbed seismic code is no longer applied since it was established rather early. This text modifies the highway subgrade vibration load by considering the seismic acceleration distribution coefficient successfully by software. The safety factor of a typical roadbed slope is calculated both under horizontal and vertical seismic load considering or without considering the dynamic magnification coefficient of slope. Through calculation and analysis, it is known that the acceleration amplification coefficient exerts considerable influence on the safety factor of slope. Therefore the acceleration amplification coefficient should be taken into account in the slope of quasi static calculation.

Abstract: Various environmental factors will adversely influence accelerometers working in the field. Mixed inputs, including external causes and the intended acceleration, are important contributors to the problem. As a consequence, calibrating accelerometers with multiple accelerations is required by manufacturers and customers. We introduce a multi-component mechanical system called vibrafuge to provide multiple accelerations. In this paper, we deduce a general model of the accelerations reproduced by an ideal vibrafuge with homogeneous transformation of matrix. Based on the model, we have an elementary analysis of the components of the output acceleration and point out two byproducts. Investigation in this paper could lay the groundwork for vibrafuge testing of accelerometers.

Abstract: Taking HYPERMESH as pre-processor, the modeling methods for a frame of the cab-over-engine medium bus in crash is expounded. Based on software LS-DYNA, the crash process is simulated with the crash regulations on M1 type bus. The deformations and energy absorbing for the parts and whole frame are analysised, especially for the invade distance and acceleration in crash. Based on these, the crash worthiness is estimated further for the medium bus.

Abstract: This paper presents a method of identification of non-homogeneity or static unbalance of the structure of a car wheel based on a simple road test. In particular a method the detection of single wheel unbalance is proposed which applies an acceleration sensor fixed on windscreen. It measures accelerations cause by wheel unbalance among other parameters. The location of the sensor is convenient for handling an autonomous device used for diagnostic purposes. Unfortunately, its mounting point is located away from wheels. Moreover, the unbalance forces created by wheels spin are dumped by suspension elements as well as the chassis itself. It indicates that unbalance acceleration will be weak in comparison to other signals coming from engine vibrations, road roughness and environmental effects. Therefore, the static unbalance detection in the standard way is considered problematic and difficult. The goal of the undertaken research is to select appropriate transformations and procedures in order to determine wheel unbalance in these conditions. In this investigation regular and short time Fourier transform were used as well as wavelet transform. It was found that the use of Fourier transforms is appropriate for static condition (constant velocity) but the results proves that the wavelet transform is more suitable for diagnostic purposes because of its ability of producing clearer output even if car is in the state of acceleration or deceleration. Moreover it was proved that in the acceleration spectrum of acceleration measured on the windscreen a significant peak can be found when car runs with an unbalanced wheel. Moreover its frequency depends on wheel rotational frequency. For that reason the diagnostic of single wheel unbalance can be made by applying this method.

Abstract: In the past, the semi-active control study generally is calculated based on the MATLAB numerical procedure, which cant achieve fine simulation. In this paper, to solve this problem, the finite element software ABAQUS is taken to be secondary development, a numerical simulation method of studying semi-active control is proposed. And the seismic response of a steel column is taken for the research. the numerical simulation analysis of the semi-active control is carried out. The results show that the control effect of the control method is significant, and the simulation result is clearly visible.

Abstract: VDI type-1 rig and JIS rig are the two major testing rigs for cleanable fabric filters. We measured the filter cleaning performance using these rigs and the results were compared in order to characterize the two testing methods. It is found that filter cleaning has no direct relation with flow type of test rig. And configuration differences between VDI type-1 and JIS rigs causes the various differential pressure development curves in which VDI type-1 rig shows a little higher cake release effect than JIS rig. Moreover, a new concept of impulse per unit area is introduced for the evaluation on filter cleaning performance in a quantitative way.