Applied Mechanics and Materials Vols. 190-191

Abstract: This paper introduces a design of active trailer steering system (ATS) for multi-trailer articulated vehicles (MTAHVs) using driver-software-in-the-loop (DSIL) real-time simulations. A yaw-plane MTAHV model is developed to derive an ATS controller. Then, the real-time versions of the controller and MTAHV models are constructed in LabVIEW and TruckSim, respecitvely. With the integration of these models, the real-time simulations are conducted with a vehicle simulator. The simulations indicate that the controller can effectively improve the MTAHV’s directional performance under the specified test maneuvers.

Abstract: Wavelet envelope demodulation method can distinguish the fault information from complex bearing vibration signal. However, traditional signal analysis method, which is solely based on a single source data, is imperfect. In this paper, an approach to wavelet packet and envelope analysis based on full vector spectrum technology was proposed. Firstly, two different data from the same source were respectively decomposed and recomposed by wavelet packet transform. Then, in order to improve the accuracy of detecting fault, the recomposed signals were merged by using the full vector spectrum method. Compared to the traditional signal analysis method, the advantage of the new method is presented by showing their application to bearings. Finally, results from the bearing vibration signal analysis show that the new approach is more effective because of its inheritance and all-sided feature.

Abstract: Attitude Control System(ACS); Terminal; Adaptive; Integral operator Abstract: Attitude Control System (ACS) with high performance, high precision, and high reliability is the kernel technology of the research of spacecraft, which directly affects the whole performance of spacecraft. Hence, a global fast integral operator Terminal adaptive sliding-mode controller is proposed to come true the high performance control. The theory of this controller is to introduce the limited time mechanics—Terminal mode to the sliding-mode control and introduce the integral operator to the sliding-mode plane, which can realize the convergence of spacecraft attitude in “limited time” in the condition of serious disturbance , in order to enhance the performance of fast response. At last, the simulation results demonstrate the high reliability and advantages of the control approach.

Abstract: Establishment of symptoms diagnostic criteria and treatment effect evaluation index system of Traditional Chinese Medicine is to improve the basic means of scientific medicine. A rational model of TCM symptoms diagnosis is to establish formation of effective evaluation index system. The study is base on the clinical data of bacterial pneumonia in the elderly. First pre-treatment basic data is proceeding. Then deleting unnecessary targets and discovering the core indicator set using Pawlak data reduction algorithms based on rough set theory, the core indicator set is determined as the diagnostic criteria of bacterial pneumonia for the elderly. The modeling method of Chinese medicine diagnosis symptoms on bacterial pneumonia for the elderly has worthy of promotion in Chinese medicine diagnosis symptoms.

Abstract: In this paper, active disturbance rejection control method is used to implement the steering angle following control of steer-by-wire system for the simplification of controller designing. The dynamic model of steering performing system is established, and then a second order active disturbance rejection controller is designed to control the steering angle. On the electric vehicle with steer-by-wire system, the angle following test of steering performing system is carried out under the control of the second order active disturbance rejection controller. The results show that the designed active disturbance rejection controller can restrain the effect of system resistant force on the accuracy of angle following and meet the requirement of steer-by-wire system to the steering angle following function. At the same time, there isn’t necessary to get the accurate data of steering system and the design process of controller becomes simple with adopting active disturbance rejection control method.

Abstract: In order to solve the problem of algorithmic complexity and large computation in Doppler radar measurement processing, a direct unscented Kalman filter is proposed in the paper. It undertakes nonlinear filtering to Doppler radar measurement in mixed coordinate directly, which makes the algorithm much simpler and reduces computation greatly. Simulation results show that the algorithm not only reaches the similar state estimation accuracy like SEKF and SUKF, but also improves the consistency of state estimation apparently.

Abstract: We design a data exchange platform with the joint topology , based on data exchange and file encryption technology of messaging middleware and integration middleware, after analyzing the requirements on how to exchange information of different application systems in different security domains. The platform achieves the purpose of exchanging information securely between different application systems and different security domains , in accordance with the requirements of relevant standards.

Abstract: Photoelastic analyses have been successfully conducted by several researchers and many equations based on digital images were presented. Although these equations were all derived using the light intensity emitted from the analyzer, pixel values of the digital image were actually used in the real calculations. In this paper, we proposed that relative light intensity should be used instead for more accurate photoelastic analysis. Real isochromatic images were generated based on relative light intensity as well as pixel value. The analysis showed that the proposed approach can obtain better result than that of the previous method.

Abstract: In order to study the tracking problem of maneuvering image sequence target in complex environment with multi-sensor array, the adaptive interacting multiple model unscented particle filter algorithm based on measured residual is proposed. The motion array tracking system dynamic model is established, and initialized probability density function also is defined based on unscented transformation, after that, the measured covariance and state covariance are online adjusted by measured residual and adaptive factor, then the self-adapting capability of filter gain and the real-time capability of posterior probability density function are improved. Finally, the simulation results between different algorithms show the validity and superiority of the presented algorithm in tracking accuracy, stability and real-time capability.

Abstract: Harmony search (HS) algorithm is a new mate heuristic algorithm, which is conceptualized using the musical improvisation process of searching for a perfect state of harmony. Its own potential and shortage, one of its main disadvantages is that it easily trapped into local optima and converges very slowly. Based on the conception of swarm intelligence, this paper presents an amended harmony search (AHS) algorithm. AHS introduces a novel position updating strategy for generating new solution vectors, which enhances solution accuracy and convergence rate of algorithm. Several standard benchmark optimization functions are to be test and compare the performance of the AHS. The results revealed the superiority of the proposed method to the HS and its three improved algorithms (IHS, GHS and NGHS).