Applied Mechanics and Materials Vols. 121-126

Abstract: A method is presented to calculate the resistance of a ship taking the effect of sinkage & trim and viscosity of fluid. The free surface flow field is evaluated by solving RANS equations with VOF method. The sinkage and trim are computed by hydrodynamic equilibrium equations. The method can be divided into direct and indirect method according to the way to calculate trim of ship. The software Fluent is used to implement this method. With dynamic mesh being used, the position of a ship is updated by the motion of “ship + boundary layer” grid zone. The present methods have been applied to the INSEAN2340 hull for different Froude numbers and are found to be efficient for evaluating the flow field, resistance, sinkage and trim.

Abstract: This paper presented a multi-channel audio signal processing platform based on TMS320VC5509A. It introduced the system basic circuit and the hardware interface design of TLV320AIC23B and TMS320VC5509A. The platform can achieve input four-channel signal and output four-channel simultaneously. Due to its low power consumption, high performance and portable feature, the platform has been used in the system of noise reduction headphone.

Abstract: Recognizing the importance of eye detection technology in face detection and recognition, facial expression recognition, driver fatigue detection, and so on, the current paper presents a novel approach to eye detection in images based on AdaBoost and the Support Vector Machine (SVM). The proposed method can accurately detect eyes with different postures, facial expressions, skin colors, and glasses in a simple background image. First, a Haar-like feature AdaBoost classifier based on the developed training samples is used to detect eyes in images. An SVM post classifier trained by coordinates of the true and pseudo eye rectangles is then used to optimize the results. Experimental results show that the proposed method is fast, robust, and has high generalization capability.

Abstract: A new method is proposed for fast computation of Zernike moments. This method presents a recursive relation to compute the entire set of Zernike moments. The fast computation is achieved because it involves less addition and multiplication operations. The experimental results show that the proposed method for the fast computation of Zernike moments is much more efficient than existing fast methods in most cases

Abstract: To accurately determine whether an image has been tampered, a robust digital watermarking algorithm based on the frequency domain was proposed. Watermarks will be embedded in the middle frequency domain of the coefficient matrix, and combining with the JPEG luminance quantization table, better balance will be achieved between the watermark transparency and the robustness of the algorithm. Moreover, before being embedded in the host image, the watermark information is encoded using the chaotic sequence, to improve the security of the algorithm. Experiment results showed that, the watermarked image generated by the proposed algorithm has higher quality. When suffering JPEG compression, cropping and other tampering attacks, the image authenticity can be determined by the similarity between the extracted watermarking and the original watermarking.

Abstract: Grinding is an important method for precision machining and ultra-precision grinding. It is used to generate parts with high surface finish, high form accuracy and surface integrity. In recent years, grinding technology in precision machining and ultra-precision machining of ceramics, glass and high-strength alloys and other hard materials has been applied widely. Grinding process is complex, once known as "black processing technology." Computer simulation is an important method to research the grinding mechanism and optimize the grinding process parameters. Especially in recent years as the development of computer calculation speed, the improvement of computer graphics theory and the gradual maturity of artificial intelligence technology, experts and scholars whose research subject related grinding had done a lot of work on grinding simulation. This paper gives an overview of the current state of the art in simulation of grinding processes: Physical simulation (material removal mechanism, grinding force, grinding temperature, etc.) and geometrical simulation (surface topography and surface integrity) are taken into account, and outlined with respect to their achievements in this paper. Furthermore, the capabilities and the limitations of the presented simulation approaches will be exemplified.

Abstract: Target image recognition is an important issue in the information processing of imaging fuse system. In the paper, the main frame is proposed which can solve the problem of target image recognition and many computer simulation experiments are carried out. A recognition algorithm based on ant colony optimization and neural network is proposed. It overcomes the shortcomings of traditional BP algorithm and converges fast. The results of experiments prove that the presented algorithm can shorten the training time effectively and increase the accuracy of recognition, so it is very useful in improving the effective destroying ability of the missile.

Abstract: Security requirements engineers usually only need provide with software security requirements, and they unnecessarily specify software security behavior mechanisms, which are critical not only for software security design but also for software security testing. After discussing the relations and differences between security use cases and misuse cases, we provides an integrated model, SETAM, for software security testing requirements, which is based on security function testing use cases and adversary testing use cases..

Abstract: Structural noise radiation prediction is the base of structure acoustic design. In order to predict structural noise radiation level of cavitation generator, Statistical energy analysis (SEA) model of cavitation generator is simplified and established. Through a series of physical and environmental parameters setting and structure modification, the sound simulation analysis of cavitation generator is conducted by AutoSEA in order to find the optimum sound structure. The results show that, appropriate increasing in shell thickness, restructuring the cavitation generator and damp applying can effectively control the structure noise.

Abstract: Aimed at the frequent accidents of conveyor belt and the the lower level of belt fracture protection in coal mine, this paper introduces a novel device equipment, the Eectro-hydraulic type Blt Cpture Dvice (Eh-BCD) to achieve safe and reliable working of steel cord conveyor belt. Firstly, after analysed the typical capture device existing on the market and researched the mechanical properties of the instant belt, an electro-hydraulic control type capture device solution was put forward, its work principle and main modules were introduced also. Secondly, main parts force of capture device calculated using Newtonian mechanics, designed and calculated the mechanical structure of the device, and determined key parameters such as installation space. Finally, after kinematic model built and analysed, device response time parameters the electro-hydraulic controlling capture was estimated.