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The sparsity rating data is one of the main challenges of recommendation system. For this problem, we presented a collaborative filtering recommendation algorithm integrated into co-ratings impact factor. The method reduced the sparsity of rating matrix by filling the original rating matrix. It made the full use of rating information and took the impact on similarity of co-ratings between users into consideration when looking for the nearest neighbor so that the similarities were accurately computed. Experimental results showed that the proposed algorithm, to some extent, improved the recommendation accuracy.

CS used in MRI image reconstruction is a research hotspot recent year. For the problem that reconstruction rate slow in MRI image reconstruction based on CS .Type acceleration Bregman iterative regularization algorithm to solve the MRI imaging sparse model ,and use the accelerate gradient method and the Restring in processing . The simulation data express this algorithm effective enhance the reconstruction rate, It’s have positive meaning in MRI image reconstruction that have strict in time requirement.

To the problem of multiple dry-reed relays electromagnetic interference in application circuits, we present an effective method to reduce the electromagnetic interference in this paper. The method is alternating permutation matrix of dry-reed relays. The paper describes the cause of electromagnetic interference of dry-reed relays. Using the offset of electric polarity alternation principle, we put forward the method for reducing electromagnetic interference. The method is applied to a multi-functional physiotherapy instrument. By experiments, experimental result shows that the degree of electromagnetic interference is reduced along with the increase in the number of dry-reed relays.

To the disadvantages, such as high energy consumption and the energy consumption imbalance, we proposed an energy-efficient routing protocol on mobile sink (MSEERP) in this paper. In the MSEERP, the network is divided into several square virtual grids based on GAF, each grid is called a cluster, and the cluster head election method of GAF is improved. In addition, the MSEERP introduces a mobile sink in the network, the sink radios in limited number of hops and uses control moving strategy, namely the sink does not collect the information until it moves to a cluster with highest residual energy. We applied NS2 to evaluate its performance and analyze the simulation results by the energy model. Simulation results show that the MSEERP balances the energy consumption of the network, saves nodes energy and extends the network lifetime.

For efficient collection of speech recordings, the ability to search for spoken terms in the speech stream is an essential capability. Although the Chinese spoken term detection (STD) does not suffer the out-of-vocabulary (OOV) problem as English, it is still hard to retrieve the long spoken terms which contain four characters or more. In this paper, we details our approach for long Mandarin spoken term detection which combines the search on inverted index produced by speech recognizer and linear scan on syllable confusion network. First, we split the long spoken terms into syllables and search the syllables on the inverted index _le to get the segments which may contain the long spoken terms. Then we use a linear scan algorithm on syllable confusion networks (SCNs). On two Mandarin conversation telephone speech sets, we compare performance using the method proposed with that of the baseline syllable-based systems, and our approach gives satisfying performance gains over the others.

This paper proposed a navigation algorithm based on indirect extended kalman filter. The algorithm adopted state error model based on sensor random walk and chose low frequency value of acceleration and angular velocity as observation. The extended kalman filter was used to calculate the optimal estimation of state error which can be used to correct the predicted value of state. IMU7200 and encoder provide acceleration, angular velocity and velocity for drill bit. Marine experiments in the East China Sea show that the proposed algorithm can successfully implement with an accurate and reliable performance.

This paper proposed a navigation algorithm based on indirect square root kalman filter. On the basis of rigorous argument about the sensor measurement error, we established state error equation based on sensor random walk model and deduced the relationship between state error and steady-state component of acceleration and angular velocity. Considered the divergence of kalman filter in the update stage, we used square root kalman filter to calculate the true value of state error which can be used to correct the predictive value of state. In order to provide acceleration, angular velocity and velocity for the proposed algorithm, we installed an imu7200 within the drill bit and mounted an encoder on the wheel of the delivery tube device. Marine experiments in the east china sea show that the proposed algorithm can implement accurate location and attitude tracking of drill bit.

Formal concept analysis and rough set theory provide two different methods for data analysis and knowledge processing. Knowledge reduct in this paper combines the two models. For an initial data sets described by formal context, look for absolute necessary attribute sets by applying rough set theory. The sets can image the concepts and hiberarchy structure completely. Then calculate the value cores of attributes values for all objects and delete redundant attributes. At last, delete repeated instances and get the minimum formal context. Construct the concept lattice of the minimum formal context can diminish the size of concept lattice of the initial table at a certain extent.

Stainless 2Cr13 is used as petroleum pipe material for its good performance in condition of high temperature, high pressure and corrosive environment. Buttress thread turning is a type of heavy machining, which has a great influence on the residual stress of workpiece. Residual stress is usually determined by cutting parameters and tool geometries. Experiments with different geometrical tools were carried out and a finite element model was used to study the influence of tool geometries on the residual stress. Experimental and simulated results showed that relatively bigger rake angle and smaller corner radius make a relatively lower tensile residual stress of workpiece surface in dry turning buttress thread.