Applied Mechanics and Materials Vols. 148-149

Abstract: Rotation symmetry is a basic type of mechanical static structure symmetry, and plays an important role in mechanical systems. Based on collecting and analyzing rotation symmetric instances, the concept system of rotation symmetry classified by the directivity of symmetry components, the rotary type of symmetry components, the alternations of symmetry components, the distributing integrality of symmetry components and the type of symmetry benchmark was established, and was explained and verified by accurate instances. The concept system of rotation symmetry can offer the academic basis to the further research on the existent type, the application methods and the application laws of rotation symmetry in mechanical systems.

Abstract: The tribological performance of pure polyamide 66 (PA66) and Carbon fibre (CF) reinforced PA66 composite were studied at dry sliding and oil lubricated conditions. The results show that the coefficient of friction and specific wear rates for pure PA66 and CF/PA66 composite slightly in increase with the increase in applied pressure values. On the other hand the coefficient of friction is in decrease while the specific wear is in increase with the increase in sliding speed values.

Abstract: According to the situation that the statistical characteristics of noise in initial alignment of sins of UKF filter is not agree with actually, the filtering precision will severely reduce or even divergent, a combination of support vector machine method of initial alignment is proposed. In this paper, the test samples are split into four groups. Three groups are trained for the first layer and the last group is trained for the second layer of support vector machine. The first layer is a group of support vector machine in parallel computing, the second layer is an information fusion of the single support vector machine in the first layer, and combined support vector machines. In this method initial alignment of strapdown inertial navigation system is achieved. Finally through the UKF filter, SVM, CSVM simulation contrast, the results show that CSVM has an improvement than a single SVM, better real-time than UKF filter and generalization ability.

Abstract: Complex equipment used in the process, due to changes in running load, vibration, shock and other incidental factors and other confounding factors can lead to changes in equipment and technology status, fault diagnosis of the current state of change brought about by these technologies use is not enough information, relying solely on traditional sensor technology can not test some special devices for signal extraction and data acquisition features. Therefore, the establishment of complex equipment and more operating conditions of knowledge acquisition simulation environment, considering the failure of complex equipment failure caused by the internal laws and mechanisms, to the essence of the phenomenon of failure analysis, combined with the physical prototype test results and raw statistical data, research the actual process of using complex equipment, considering the state of properties, condition monitoring parameters and the integration of traditional knowledge, expertise and reasoning techniques to be applied to physical prototype of a certain conclusion, not only for the early prediction of potential failures, laid the theoretical foundation for forecasting , and fault prediction system for the complex equipment, the development provides important data and technical support to solve the complex equipment maintenance and support tasks needed problem.

Abstract: There are always lots of speckle noises in medical ultrasonic images because of the imaging mechanism of it. These speckle noises significantly reduce the clarity of the image and as a result, cause great difficulties in ultrasound diagnosis. To solve this problem, this paper presents a new de-noising method for medical ultrasonic image based on ROF model and adaptive wavelet threshold de-noising method. In addition to inhibiting the speckle noises in the medical ultrasonic image, this method can retain and even enhance the image detail information as much as possible.

Abstract: Through analysing technology and principle of sewing thread tube packing, a kind of sewing thread tube packing device was designed, and the mechanical, pneumatic and control system were designed. Using the device, the result of the Packaging tests verified all sorts of function. It has a positive meaning to improve the production efficiency in Textile enterprise.

Abstract: Heat exchanger network synthesis has been one of the most popular subjects in process design over the last 50 years. Various studies and optimization techniques have been proposed for designing optimal network with minimum total annual cost. Simultaneous synthesis approach via mathematical programming aims to find the optimal network without decomposition, which has been paid more attentions on the research recently. However, these methods might be not solvable or inefficient for large-scale problems. This paper makes an attempt to construct simultaneous synthesis model with split streams and to develop an efficient optimization framework based on particle swarm optimization for large-scale heat exchanger network synthesis problems. One example including 20 process streams is solved to give an illustration of the method.

Abstract: Refinery crude preheat train (CPHT) is prone to fouling and ageing effects due to the complexity of processed crude feedstock preheated prior to distillation. This has serious implications on the thermal and hydraulic performance of the CPHT. As a result, efficient performance of crude preheat trains is compromised and as such, optimal scheduling cleaning operations are required to restore performance. In this paper, we attempt to review the subject of fouling/ageing control and mitigation in crude preheat train network by optimal scheduling cleaning approach. Three prominent optimisation techniques/models namely Mathematical Models (Mixed integer linear programming (MILP) and Mixed integer non-linear programming (MINLP) models); Artificial Intelligence (AI) Models; and Heuristic Techniques used for achieving optimal cleaning are outlined.

Abstract: The main idea of this paper is to calculate the entire process capability of the Complex Product Machining Process (CPMP) based on modified tradition process capability index and then further decide the improvement orientation and size to individual process parameter through sensitivity analysis. We illustrate the method by a three-stage machining process. The results have shown that the proposed method could significantly improve the process capability.

Abstract: The subject of this paper is introduction of invent and upgrade chess as a Complex mathematics model simulating ancient city attack and defend war. Upgrade chess is development to traditional chess and giving up traditional chess game's imperfection. The design ideas of upgrade chess based on Chinese traditional TaiJi philosophy concerning Yin and Yang, and combine western dialectics and structuralism philosophy: the various elements of the chess including pieces and chessboard form organic connection system for both sides checkking each other and mutual competion. Upgrade chess is "mental gymnastics" and "chess football", as well as a extremely challenging mathematical problems. Upgrade chess as software can provide intelligent control for various cultural industries, e.g., can be applied to sports competition, online games, cultural entertainment, sports related handicrafts, media coverage industry and so on. Thus it has potential to form large scale economic benefits.