Applied Mechanics and Materials Vols. 556-562

Abstract: In this paper structural equations of motion based on nonlinear beam theory and the unsteady aerodynamic forces are gained to study the effects of geometric nonlinearity on the aerodynamic response of high-aspect-ratio wings. Then the Galerkin’s method is used to discretize the equations of motion. The results of HALE wing show good agreement with references. And other results investigate the effects of geometric structural nonlinearity on the response of a wing. Also the complex changes of the limit-cycle oscillation with speed increasing is carefully studied.

Abstract: In this paper, we introduce and study a Crowley-Martin type Chemostat model with delayed growth response and pulsed input. We get that the existence and the global attractivity of a ‘microorganism-extinction’periodic solution. We prove that the system is permanent under appropriate conditions, by use of new computational techniques for impulsive and delayed differential equation.

Abstract: A whole new design optimization strategy for the plate finned-tube heat exchanger (PFTHX) was provided. According to the industrial application of the domestic heat exchanger manufacturers, the tube arrangement, fin number, etc. of a PFTHX with designated coil can be sifted stage by stage with: (1) the confine of size parameters of the coil, tube passes, the flow velocity of the fluids of both sides, (2) the confine of the pressure drop of the fluids of both sides, (3) the margin of heat transfer area, etc. The calculation amount can be reduced significantly and at the same time, all the solutions meeting the thermal indices and discrete design parameters can be obtained.

Abstract: The paper proposed the practical metal cutting process using FEM to simulate the traditional cutting process, the simulation and the analysis of the results are based on the support of DEFORM-3D finite element software, and the characteristic between Galerkin Algorithm and FEM analysis is also analyzed. Then the paper processed the modeling procedure for FEM using Lagrange and Euler algorithm, the simulation result is then compared to traditional ones and proved to be more efficient and with higher accuracy.

Abstract: The position extraction of lower limb joint points is important for gait recognition because the feature data is always based on the position of lower limb joint points. Since the detection of motion information of human body can affect the gait recognition directly, we propose a position extraction method of lower limb joint points in this paper. Through the study on the human body centroid tracking, and positioning of human lower limb joint point, we can obtain the step cycle information. It has been demonstrated via plenty experiments that the proposed method is feasible and easy for implement, since it can achieve real-time tracking and improve positioning accuracy of the human body joints, and can provide feature data for human gait recognition.

Abstract: UAV Video is rapidly emerging as a widely used source of imagery for many applications in recent years. This paper presents our research on the mosaic of UAV video for the purpose of harbor surveillance. First, one new framework on estimating video frame transformation with Optical flow is presented in this paper. For this new framework, fewer number of Gaussian pyramid is created for implementing for the multiresolution approach and thus, more details for optical flow computation is well kept; Second, we make a discussion on using Fourier-Mellin Transformation in image frequency domain to estimate initial motion parameter of adjacent video frames and with those initial motion parameters, small displacements for optical flow computation can be achieved; The experimental results demonstrated that the mosaic image generated from aerial video shows satisfied visual quality and its surveillance application for fast response to time-critical event, e.g., flood, is descried.

Abstract: For the disadvantage of traditional direction index histogram (DIH) handwriting identification method, an improved text-independent handwriting identification algorithm is presented. The handwriting image which is prepared to test needs pre-processing, then the normalized image can be obtained. Based on the features distance two factors can be extracted: the writing influence factor and the character influence factor. Compared the features of the handwriting image which is prepared to test with the features of the sample handwriting image, The better handwriting identification accuracy rate can be obtained, which provides problem-solving method for text-independent handwriting identification.

Abstract: The exterior ballistic measurement is the basis of the precision analysis for the vehicle experiment, and the distribution geometry of the velocity measurement system has important influence on the estimation precision of the exterior ballistic measurement data. This paper proposed an optimization method for distribution geometry of the velocity measurement device by PSO, and the optimized project under the unconstrained and constrained which the alternative sites have been given is obtained. The simulation results show the effectiveness of the optimization method for distribution geometry.

Abstract: Motion Vector Prediction (MVP) plays an important role in improving coding efficiency in HEVC, H.264/AVC and AVS video coding standard. MVP is implemented by exploiting redundancy of adjacent-block optimal coding information under the constraint that MVP must be performed in a serial way. The constraint prevents parallel processing and MB pipeline based on LevelC+. In multi-stage pipeline, to some extent, adjacent-block best mode-decision information can hardly be obtained. In this paper, we propose a new hardware-oriented method to improve the coding performance at a cost of few hardware resources. When adjacent block is not available, spatial motion vector prediction (SMVP) for integer motion estimation (IME) and fraction motion estimation (FME) will take the IME best mode information and FME best mode information of left block as best information to derive PMV (Predicted Motion Vector) for current macro-block or block. Experimental results shows that the method we propose can achieve a better performance than the existing methods by 0.1db for the cases with intense movement and a non-degrading performance for flat cases.

Abstract: In order to estimate the attitude fast and accurately for the underwater glider using the lower cost and lower power underwater navigation system, this paper designs a new underwater navigation system which is made up of the inertial sensors aided the magnetometer and proposes an improved unscented Kalman filter based on decimation in frequency domain fast Fourier transform (UKF-DF). UKF-DF makes better use of the estimate advantage of UKF in the nonlinear system, and in this basis DIF-FFT is integrated into UKF to increase the speed of calculation. Therefore, the attitude of a glider can be estimated fast and accurately. The real vehicle experiment is done to assess the performance of the proposed UKF-DF algorithm, the experimental results show that the attitude convergence of UKF-DF is better than EKF (extended Kalman filter) and the attitude estimated by UKF-DF is more precise than EKF.