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Soil materials can exhibit strongly dispersive properties in the operating frequency range of a physical system, and the uncertain parameters of the dispersive materials introduce uncertainties in the simulation result of propagating waves. It is essential to quantify the uncertainty in the simulation result when the acceptability of these calculation results is considered. To avoid performing thousands of full-wave simulations, an efficient surrogate model based on artificial neural networks (ANNs) is proposed in this paper, to imitate the concerned ground penetrating radar (GPR) calculation. With the autoencoder neural network to reduce the dimensionality of data, the surrogate model successfully predicts the outputs of the GPR calculation using a small number of training samples. The finite-difference time-domain method with the uniaxial perfectly matched layer is used to collect sampling data for the surrogate model. The process of constructing the surrogate model is presented in detail in this paper. The proposed surrogate model is demonstrated to be an attractive alternative to the full-wave GPR calculation due to its considerable advantage in terms of computational expense and speed.

With the continuous development of cloud storage technology, more and more users choose to store their data to the cloud server to save local storage costs, but at the same time, they also lose direct control over their data, so ensuring data integrity becomes a challenge. A cloud storage data integrity verification scheme based on Dynamic Array Multi-branch Tree (DA-MBT) is proposed. The leaf node is set as an array structure, which reduces the height of the tree, improves the utilization rate of nodes, simplifies the process of dynamic update, reduces the query time of the data block, and improves the verification efficiency. Finally, it can be concluded that, the proposed DA-MBT scheme supports full dynamic operation, realizes the privacy protection of users, can effectively verify the integrity of a large number of data, and can effectively reduce the communication and computing overhead during the verification process.

The problem of the scattering of SH waves by a circular hole in two-dimensional inhomogeneous medium is discussed in this paper. Based on the conformal mapping technique, the Helmholtz equation with variable coefficients is transferred into its standard form. Besides, the dynamic response is calculated and discussed. Numerical results present that DSCF is influenced by wave number and inhomogeneous parameter.

The synchronous reluctance motor (SynRM) is widely used because of its excellent performance such as high efficiency and accurate speed control. In this paper, the rotor with the squirrel cage consisted of three design parts is shown. An additive manufacturing method (selective laser melting) for fabricating the three parts of the rotor in one build is shown. A complex SynRM based on selective laser melting of the new rotor is carried out.

The first cold dielectric insulation (CD) high temperature superconducting (HTS) cable system of China, installed in Baoshan iron&steel Co., Ltd (Baosteel), begins its operation and supplies power for the second EAF on Dec 9th, 2013. The system is a three-phase system with rated capacity of 120 MVA (rated voltage 35 kV, rated current 2000 A). The cables' length is 50m for each phase. The cables were made up of 2 G HTS tapes which were provided by AMSC. An unmanned remote control power station has been built by employing high-intelligent control and communications technology. The project is funded by Science and Technology Commission of Shanghai Municipality (STCSM) with the leadership of Shanghai Electric Cable Research Institute (SECRI). Shanghai Sanyuan Cable Accessories Co., Ltd., BaoSteel Co., Ltd., and Shanghai Electric Power Design Institute Co., Ltd. (SEPD), are the main partners. Shanghai University, Shanghai Jiaotong University and Shanghai Cable Co., Ltd. are also involved in the projects.

Synchronous reluctance motors (SynRM) have been widely used because of their excellent performance, such as high efficiency and accurate speed control. This paper focused on the efficiency and starting ability of SynRM. Based on the view of steel sheet material and motor fabrication, the iron loss influences on SynRM regarding different grades of silicon steel are compared, and the performance of a squirrel cage assisted SynRM is investigated. Moreover, a new fabrication involving additive manufacturing (namely 3D printing) and a new high conductivity magnetic powder for facilitating the new SynRM fabrication process are proposed.

Optimal beamforming on synthetic noise and interference is a flexible and intuitive technique for shaping beam patterns. In this method, suppression of arrivals from undesirable directions is achieved through introduction of synthetic interferences and optimal beamforming using the resulting noise-interference covariance matrix. We apply this approach to a general multiplet line array and test the algorithm on representative multi-channel time-series obtained for a quadruplet line array.

Conservative therapy for intraspinal tumor is mentioned very often in the literature. However, there is no clear reference on surgical method choices for intraspinal tumors. Therefore, we conducted a systematic review to investigate the difference of preoperative and postoperative symptoms between the hemilaminectomy (HEM) and laminectomy (LAM) on intraspinal tumor. A computer based online search of the computerized data bases MEDLINE and PUBMED and EMBASE and ISI Web of Science for articles published from 1970 to January 2011 was performed. Studies that compared hemilaminectomy with laminectomy were included. Data were evaluated by RevMan 5.0 for the systematic review. Six eligible trials including 409 intraspinal cases were considered. The systematic review indicates that hemilaminectomy was more efficient in the improvement of early symptoms than laminectomy. The combined odds ratios (OR) were 2.82, with 95% confidence intervals (CIs) (1.75–4.54). The systematic review indicates that hemilaminectomy was more efficient than laminectomy in the improvement of advanced symptoms. The combined OR was 2.42, with 95% CI (1.56–3.74). In the case of appropriate surgical indications, the choice of hemilaminectomy was better for improving symptoms as cerebrospinal fluid leakage, infection, poor circulation and other possible complications for patients with intraspinal tumor.

GBA(Group-Buying Auction) is coming to be an important part of online auction. Most of the previous studies about retailers' ordering strategy were in two retailers, and the current conclusion is that the retailers will buy more products in the GBA mechanism than in the fixed-price mechanism in the case of two retailers. As long as the threshold is not too high, the profit and the service level of the retailers can be improved. This paper studies the optimal ordering strategy based on GBA in more than three retailers, and the previous conclusion still tenable in this case.

With the rapid development of our country, the demands of steel, timber and other bulk goods are greatly increased, the transportation becomes even more important and complicated. For the difference of vehicles' loading capacity, in the process of transferring vehicles, it is likely to cause surplus. In this paper, we study on the handling of the surplus bulk goods due to the transferring vehicles in purchasing and transportation. In order to choose the best handling mode for the surplus, we establish a model of dynamic programming. In the model, we want to satisfy customers' needs first, then try to reduce the inventory and make the total costs minimized. At the end of the paper, a timber retailer who imports Russian logs is taken as an example to verify the correctness of the model. The results of the paper can provide some reference for the retailers of bulk goods.

Objective: To assess the bone protective effects and mechanism of Polygonatum Sibiricum Polysaccharide (PSP) in ovariectomized rat. Methods: 60 female SD rats were randomly separated into 6 groups:control group (n=10); ovariectomized group (OVX) (n=10); the OVX + E 2 group(OVX + E 2 ) (n=10); the high-dose OVX + PSP group (OVX + HZ) (n=10); the moderate-dose OVX + PSP group (OVX + MZ) (n=10); the low dose OVX + PSP group (OVX + LZ) (n=10). PSP was administered intragastrically to the rats. After 35 days, the total body Bone mineral density (BMD) was assessed in the rats. All sections were processed for hematoxylin-eosin staining (H.E.), and Basic fibroblast growth factor (bFGF), Tartrate-resistant acid phosphatase (TRAP), Bone morphogenetic proteins (BMP), and Bone Gla protein (BGP) immunoreactivity was assessed. Serum tumor necrosis factor-α (TNF-α) and bone specific alkaline phosphatase (BALP) levels were assessed using commercially available ELISA kits. Results:The expression of BMP and bFGF were significantly increased in OVX+HP. The expression of TRAP, TNF-α, BGP and BALP were significantly decreased in OVX+HP. BMD was significantly increased in OVX+HP(vs. OVX, P

With the development of offshore oil and gas fields, research on the protection of submarine pipeline which is one of the most important aspects of an offshore oil field exploitation system, becomes more important. In this paper, a series of experiments has been conducted to compare the effectiveness of rigid spoilers installed on the top of the pipeline with the effectiveness of flexible spoilers installed on the bottom of the pipeline and in an attempt to find a better way to protect the pipeline from floating even fracturing. Scours depth and width around the pipeline with different lengths of spoilers were measured and analyzed. It was found that the scour depth reached the maximum value 0.5D when the flexible spoiler length attained the critical value of L=0.35D, which was much bigger than it with a rigid spoiler, furthermore, the scour width was narrower than the rigid one. Therefore it is a better way to make the pipeline self-burial.

In this paper, a new type of sound-absorbing film material was made, using polyaniline (PAN) doped graphite (G) as the basis, polymer as the film forming agent. Factors which affected the sound absorption properties were discussed, the results showed that sound absorbing properties were the best, when Surface resistance was 103Ω, film thickness was 300µm. On this condition, average absorption coefficient was 0.6, and the maximum value was 0.97.

The conventional neural networks which are limited to two-state neurons are not able to solve the problem of blind multi-state signal detection. A new algorithm based on discrete complex-valued Hopfield neural network(DCHNN) is proposed to detect MPSK signals blindly. Based on the energy minimization performed by the network, this paper suggests an direct design procedure that gives a Hermitian weight matrix such that each constellation signal in the MPSK state space is an attractive fixed point of the network‥ Simulation results show that the algorithm reaches the real equilibrium points and show satisfactory performance in detecting MPSK signals blindly.

Relevance feedback is an iterative search technique to bridge the semantic gap between the high level user intention and low level data representation. This technique interactively determines a user's desired output or query concept by asking the user whether certain proposed 3D models are relevant or not. For a relevance feedback algorithm to be effective, it must grasp a user's query concept accurately and quickly. In this paper, we propose a relevance feedback framework based on Bayesian logistic regression in content-based 3D model retrieval systems to incorporate relevance feedback information. Bayesian logistic regression relevance feedback framework using an active learning algorithm based on variance reduction to actively select documents for user evaluation. Experimental results show that this algorithm achieves higher search accuracy than traditional query refinement schemes.

As mobile game grows rapidly in recent years, it becomes one of the new economic contributors to the game market. However the low-powered mobile device is the main barrier for the quick development of mobile game. Through mobile billiards game on the e868 mobile phone of the Bird-company, a game development framework for low performance mobile device is designed in this paper. To improve both the speed and visual effect of the game, this paper proposes an efficient collision detection algorithm suitable for mobile games from the aspect of game logic. Combined with the features of low-powered mobile devices, many different optimization techniques are presented and implemented.

Relevance feedback is an iterative search technique to bridge the semantic gap between the high level user intention and low level data representation. This technique interactively determines a user's desired output or query concept by asking the user whether certain proposed 3D models are relevant or not. For a relevance feedback algorithm to be effective, it must grasp a user's query concept accurately. In this paper, we propose a relevance feedback framework based on Hidden Markov Model Regression (HMMR) in content-based 3D model retrieval systems. Given a 3D model retrieval system, we collect and store user's feedback and use HMMR to enhance the retrieval performances. Experimental results show that this algorithm achieves higher search accuracy than traditional query refinement schemes.

Relevance feedback is an iterative search technique to bridge the semantic gap between the high level user intention and low level data representation. This technique interactively determines a user's desired output or query concept by asking the user whether certain proposed 3D models are relevant or not. For a relevance feedback algorithm to be effective, it must grasp a user's query concept accurately and quickly. In this paper, we propose a framework called fuzzy relevance feedback in content-based 3D model retrieval systems. Fuzzy relevance feedback is to integrate the users' fuzzy interpretation of semantic content into the notion of relevance feedback. Experimental results show that this algorithm achieves higher search accuracy than traditional query refinement schemes.

The conventional neural networks which are limited to two-state neurons are not able to solve the problem of blind multi-valued signal detection. A new algorithm based on discrete Hopfield neural network(DHNN) is proposed to detect multivalued signals blindly. A discrete 4-level signum-type activation function is constructed for 4PAM signals. For the blind signal detection, the optimization performance function is constructed and it does not rely on the second or higher order statistics of the received signals. Based on the new weight matrixes and the energy function of multi-value DHNN, the stability for multi-value DHNN is also proved in the paper. Simulation results show that the algorithm reach the real equilibrium points in a few iterations and show high speed to blindly detect multi-valued signals in stochastic channels.

Relevance feedback is an iterative search technique to bridge the semantic gap between the high level user intention and low level data representation. This technique interactively determines a user's desired output or query concept by asking the user whether certain proposed 3D models are relevant or not. For a relevance feedback algorithm to be effective, it must grasp a user's query concept accurately and quickly. In this paper, we propose the use of biased support vector machine active learner for conducting relevance feedback for 3D model retrieval. The algorithm selects the most informative 3D models to query a user and quickly learns a boundary that separates the 3D models that satisfy the user's query concept from the rest of the dataset. Experimental results show that this algorithm achieves higher search accuracy than traditional query refinement schemes.

Blind nonlinear channel equalization using kernel processing is proposed, which transforms blind equalization of nonlinear channel to formulate as a convex quadratic programming using kernel processing. The novel method acquires the optimal solution by solving a set of linear equations instead of solving a convex quadratic programming problem. It is shown the kernel processing equalization by adopting Gaussian cost function has several merit, such as: 1) The quadratic programming problem solved at each iteration is convex and has a globally optimal solution. 2) It avoids the difficulty of choosing the suitable parameters of the kernel function to obtain the satisfied blind equalization performance. 3) It need only 20% data samples of support vector machines (SVM) method to obtain the same blind equalization performance. 4) It is more robust for more nonlinear channels.

Knowledge of topology in wireless sensor networks is significant for networkmanagement _and maintenance. In this paper, a conditional probability of data loss theorem is proposedfor wireless sensor networks based on the data aggregation paradigm.al probability of data loss therem iIt reveals the relationship between conditional probabilities of sensor data loss given different conditions. Based on this theorem, we propose a novel algorithm to infer topologies of sensor networks using end-to-end loss measurements. The algorithm does not incur any additional burden toon the network. A large number of networks are simulated in different scenarios with NS-2. The results show that our proposed algorithm can identify more than 95% of topologies within a small data collection rounds.

The paper presents a concept and framework of a vision system for observing satellite in close quarters. The vision system uses natural features on the satellite surfaces instead of artificial markers for its operation, computes relative motion and structure of the target, and tracks features in image sequences. The vehicle equipped with the system can navigate automatically and freely around the satellite for reconnaissance and surveillance. Selected algorithms of the system have been characterized in ground environment; they are undergoing systematic sets of adaptation for space.

Binary image matching plays an important role in pattern recognition and image process. A variety of methods have been proposed that enable the efficient querying of binary image repositories for a desired binary image shape. In this paper, we consider the implications of anisotropy transform on the binary image shape matching. We describe the properties of anisotropy transform and show how this approach can be applied to improve the matching performance of many existing shape matching methods.

In this paper, our work on heteroepitaxial SiC films deposited on single-crystalline (111) silicon by hot filament chemical vapor deposition (HFCVD) at low temperature of 800 degC is reported. The surface topography of SiC films on Si substrate were analyzed by atomic force microscope (AFM). The characteristics and crystallinity of the SiC film were examined by X-ray diffractometer (XRD) and Fourier transform infrared (FTIR). As can be seen in XRD spectrum, the peaks of Si (111), SiC (111) and SiC (222) appeared. And TO-phonon absorption peaks (804.95cm-1) of Si-C bonds also emerged in Fourier transform infrared spectra. In particular, intensive visible-light emitting at 411nm and 43 6nm has been observed at room temperature in photoluminescence experiments

This paper presents a recursive algorithm of combinational optimization to blindly recover transmitted sequences of any length. The recursive algorithm is obtained by using a moving window with a forgetting factor. The exact initial sequence of the recursive algorithm is provided by quadratic programming, whose cost function is formed by using the residual in the left complement subspace of a received data matrix. Simulation results show that the algorithm converges quickly and has small bit error rate in blind recovery of input sequences.

This paper firstly derives an ARMA model for channels with common zeros. Then, based on this model, the blind signal recovery problem is reduced to a quadratic optimization with integer constraints through the generalized complementary projection operator of the subspace spanned by a received data matrix. Finally, the recovered signals are used to identify the SIMO channels. The theoretical analysis and simulation results show that the generalized complementary projection algorithm proposed has the excellent performance in blind signal recovery and channel identification, whether the SIMO channels have common zeros or not, in or outside of the unit circle.

Man has been exploring continuously to improve the precision and intelligent degree of IR in order to deal with large quantities of information. In traditional methods of IR, retrieval results are disposed so little that the quality of IR is not high. To overcome this issue, a clustering algorithm based on cut-set is designed in this paper. This algorithm carries through clustering based on no leading text choice to many retrieval results so that users only consider the relevant sub-classes and abandons the non-relevant data. Hence, users can browse fewer documents. Experiments on live data of text snapshot show this algorithm can improve the query efficiency of IR system considerably at the cost of much less time.

This paper presents the design and implementation of a storage battery performance testing system (SBPTS) controlled with an 8098 chip microcomputer. The SBPTS is composed of three units: charge unit; discharge unit; and microcomputer control unit. The 8098 chip microcomputer used in this system shows its high integration and good ability including A/D and D/A conversions, data processing, output control and disturbances rejection, etc. >