Applied Mechanics and Materials Vol. 483

Abstract: Based on the mean-value theorem of the engine, the mathematical models can be created for the four-stoke-cycle-CNG engine, style of YN30QNE. Furthermore, while the mean-value models set the basis for the external loading resistance model controller, the adjust-dimention-burning engine models give birth to the models, as well as the MAP figures, of the engines controlling of the advance angle of ignition. Finally what the tests show us are as follows. Firstly the advance angle of ignition does the same, as the rotating velocity increases, and on the condition of the same rotating velocity, the best suited advanced angle of ignition decreases reversely with the growing loading resistance of the engine. Secondly it not only brings us the rarely precise original MAP figures of the advance angle of ignition, but also shortens the development cycle. Lastly, in the process of the calibration, optimal functions are used to conduct the PID optimal designing for the external loading resistance controller, which makes the system converge faster, improves the efficiency of the calibration as well as optimizes the results of the calibration.

Abstract: In this paper, a heuristic Multivariant Optimization Algorithm (MOA), which has the ability to locate multiple optima through alternating global-local search iterations by multivariant search groups including global exploration groups and local exploitation groups based on a structure where the optimizing process is saved, is described in detail. The performances of MOA are compared with that of other heuristic algorithms including GA and PSO based on six benchmark functions and the experiment results indicate that MOA outperforms GA and PSO in success rate and convergence efficiency on multimodal functions.

Abstract: Multivariant Optimization Algorithm (MOA) is a newly proposed algorithm and its multi-group property make it a perfect choice for multimodal optimization. In this paper, an absorption mechanism was introduced into MOA to remove the redundant search information that stored in the structure and we named the proposed algorithm as the Absorption Multivariant Optimization Algorithm (AMOA). With this mechanism, more search information will be captured and the search information will be shared more effectively. The proposed algorithm is tested on nine benchmark functions to compare the performance with standard MOA under the same condition. The experimental results suggest that the improved algorithm can keep high success rate as the number of global optima increase and the output result would be more stable.

Abstract: The paper focuses on the design of an onboard track fault diagnosis device for advanced railway condition monitoring which can be mounted on in-service vehicle. Track faults are diagnosed from the vertical and lateral acceleration of axle-box, bogie and car-body with different characteristics. As vibration signal in time-domain will not represent the condition of the track obviously, the signal is transformed into frequency-domain first. Then PCA and SVM are used to calculate probabilities of fault tracks. At last, The D-S evidence theory is employed in the track fault diagnosis to fuse multi-source information. When fault is detected, alarm message will be sent to the monitoring center of the system to ensure the safety of the following vehicles. Experiments which use three accelerometer signals in different positions as mentioned above from the inspection vehicle were carried out to show that the detection algorithm is effective to estimate the rail irregularities and diagnose track faults.

Abstract: This article analysis the game relationship between local governments without cooperation or not by the game theory during the recycling process of ELV, and then get the optimal strategy choice. Results show that regional income and environmental monitoring are the important factors that affect regional game, as a result, although our country has clearly defined the responsibility of" supervision and management " to local government in the reverse logistics of ELV, this can only play a guiding significance in the process of implementation and the operability is not strong. So we should need to improve the management of special funds, strengthen financial support, adjust the national industrial development policy, establish a regional mechanism of cooperation, setting the development goals scientifically of the recycling industry of ELV, and do further refinement of local government powers and duties, so as to promote the development of recycling industry of ELV healthily.

Abstract: Under the condition of limited information on route, incomplete check, minimum maintenance and other characteristics, it will be that the concept of reliability estimate extended to real-time application of reliability. The single remaining life prediction method based on HOLT algorithm to solve dynamic use under the environment of residual life prediction problem. Case analysis results show that the method of forecasting precision can get the engineering application requirements, so it is effective and feasible.

Abstract: A topology optimization method of thin-shell frame with surface loads is proposed in this paper and the mathematic model of this topology optimization method is introduced. Based on this proposed method, the procedure of lightweight design for special-shaped container is introduced, then, the lightweight design of 30t special-shaped container of heavy-duty dump truck is carried out. The result shows that the proposed method is very practicable and effective.

Abstract: The green characteristic of household split air conditioners can be inproved by reducing the noise or improving the energy efficiency. Therefore, a finite element model of outdoor units duct system was built with Fluent considering the coupling of separated components. Based on the simulation results, the flow field of duct system was analyzed, and the structure of fan cowl was optimized to decrease the export eddy. Experiments were done to proved the effectiveness of the modelling and optimizing process.

Abstract: Product family is a series of products with similar characteristics. It is a strategy used by modern enterprise to achieve product diversification with limited development, manufacturing and service. Product DNA is the design commonality of enterprises product family, it is distinctive and aesthetic by reflecting the company's brand value and design concept, in addition ,it include some essential elements such as form, color, material and composition. This paper introduces the methods of drawing product DNA and analysing the relevance of design features to brand style by case study.

Abstract: It is important to develop an application to manage knowledge for reusing as efficiently as possible. Knowledge management in advanced manufacturing industries is a complex process. In this paper, user needs for design knowledge management are gathered from interviews with users and during brainstorming sessions. The main requirements for design knowledge management are such as: design knowledge normalizing, design case normalizing, knowledge tracing, generating know-how knowledge, learning failure case knowledge, and design knowledge management in product lifecycle, etc. Knowledge application scenarios for a new paving machine design are studied which would enable software function development.