Applied Mechanics and Materials Vols. 201-202

Abstract: The Naive Bayesian classifier is the least sensitive to missing data in the methods of data mining. However, missing data still affects the accuracy of the classifiers before the dataset which contains missing data used to train in the classifier. We can fill up the missing data to gain a full dataset. This paper introduces a random patch algorithm based on Markov Transition probability. This algorithm can fill up the dataset which contains missing data to a full one. Using the full dataset to classification can increase the accuracy of the classifier. We perform experiments to prove the algorithm effectiveness.

Abstract: In view of present situation that fixture for standardized cutter can install only one specification of standardized cutter and center height of cutter blade must be calibrated by gaskets, a new-style multi-functional fixture was designed which can clamp various specifications of standardized cutters and be adjusted more precisely and easily by screws. The main design contents include general structure of fixture, installation space of cutter, harford vertical adjusting mechanism, cutter lateral fastening and screwdown column; lateral fastening force, screwdown clamping force and tighten torque of different specifications of cutters are calculated afterwards. It has been proven by practices that the new fixture has good effects and meets demand of production well.

Abstract: A finite element approach based on Ansys is developed to simulate stress intensity distribution in a three dimensional model of coupling clamp joint, which includes ferrules, pipe caps and bolts. The characteristics of stress intensity distributions of coupling clamp joint under strength pressure loading have been studied by means of the non-linear finite element method. The FE model can also predict the clamp quality and tolerances to be expected under different process conditions and define the most effective process parameters to influence the tolerances. The study could give us a better understanding on the mechanism and basis for optimization design of the coupling clamp joint.

Abstract: In wireless sensor networks, power consumption is the most important issue. That is wireless sensors are normally deployed into unattended places where power of sensors is hard to be charged. Indeed, the network lifetime of wireless sensor networks equipped with city power or deployed into attended place is much longer than those wireless sensors equipped with batteries. In general, wireless sensor nodes are connected together and become a network after deployed into certain places. With the certain range places that wireless senor nodes deployed into, finding the optimal clusters can increase the entire network lifetime. Also, adding the forwarding station extends the network lifetime. Therefore, this paper proposes the integration of both the forwarding station and optimal clusters in ad-hoc wireless sensor networks. Simulation results show that the entire network lifetime proposed is extended in this paper compared to both optimal cluster number selection and normal forwarding station.

Abstract: The design of mechanism scheme is the primary phase and the creative and challenging part in product lifecycle. In this paper, we research the multiple attribute group decision making (MAGDM) problems for evaluating the design of mechanism scheme with uncertain linguistic variables. We employ the uncertain linguistic weighted harmonic mean (ULWHM) operator to aggregate the uncertain linguistic information corresponding to each alternative and get the overall value of the alternatives, then rank the alternatives and select the most desirable one(s) by using the formula of the degree of possibility for the comparison between two uncertain linguistic variables. Finally, a practical example for evaluating the design of mechanism scheme is used to illustrate the developed procedures.

Abstract: In order to smooth point-based surface with noise, Bezier surface fitting method was applied to compute principal curvature and normal vector at each point. We construct an undirected weighted graph from scattered points, and a heat diffusion partial differential equation was defined on this graph. Considering principal curvature as heat power, the smoothing process is realized by diffusing principal curvature along graph structure. We adapt the position of each point along normal direction according to the difference of curvature. Computing heat diffusion equation can be boiled down to the spectral decomposition of Laplacian matrix. We use parallel computing method to solve the spectral decomposition of Laplacian Matrix on GPU to improve the efficiency. Some examples show that our method works well on complex models with large scale point sets.

Abstract: According to the characteristics of machine tools such as complex driving chain ,weak signal and enclosed housing,this paper takes horizontal lathes as study objects and selects current signal which is easy to sample as the analytical signal.We collect motor load current signals of idling, cylindrical cutting and end cutting processing state in the experiment to process the condition monitoring based on wavelet denoising and wavelet packet transform. We take advantage of the threshold denoising method to reduce noise of load current signal.Then we use time-frequency analysis methods of wavelet packet transform to extract state characteristic quantity and outstand useful information.So in this paper we monitor the working state of lathes based on the unique advantages of wavelet denoising and wavelet packet transform, and this method can be widely used in various fields of state monitoring.

Abstract: Explore the influence of gas flow conditions geometry of the diesel spiral airway, which predict the performance of the design of the airway. And the direction of improvement and optimization theory, using CFD technology to explore such away preliminary attempt, based on Pro/E to build the model of airway fluid entity, and use a common geometric standard model into the finite element analysis software ANSYS to analyze to get the airway export velocity distribution, turbulent kinetic energy distribution and other results. It is assessed on eddy current level of Angular momentum flux, and airway improved.

Abstract: Based on the analysis of routing algorithm of typical wireless sensor networks, the author puts forward with the objectives of routing algorithm and designs energy-aware routing algorithm to reduce energy consumption and extend life cycle of the whole network. The algorithm constitutes four modules: clustering module, dynamic cluster head election module, dormant state module and inter-cluster routing module. Aiming at effectively using the energy of sensor nodes, the paper makes use of honeycomb-like two-level clustering structure to increase coverage rate of nodes. Also, studies of routing are discussed on the two aspects, being the inter-clustering dynamic cluster head election and introduction of dormant mechanism, and secondly, the inter-clustering reliable routing.The routing algorithm has its prototype realized and effectively verified on the test bed provided by the laboratory.

Abstract: An automatic greenhouse seedling monitoring system that can make use of solar energy as power supply to conduct regular monitoring and collect air temperature, air humidity, soil temperature, soil water demand and other parameters is designed. The collected data will be transmitted wirelessly to the upper PC system of host and then, the PC system will compute and process such large amounts of data timely and automatically and carry out corresponding operations for greenhouse through automatic control of feedback signals. With the large capacity of data acquisition, reliable data transmission, humanistic data processing, easy operation, this system will have great practical use. Through the application of this system, it can greatly reduce labor intensity and improve the level of scientific breeding and thus bringing out high quality seedlings to ensure and improve crop yields. This system is feasible and has certain practical value.