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4057篇 您的检索式:期刊名="Comput Electron"
    题名 作者 年代 出处 被引量
1SCKF-STF-CN:a universal nonlinear filter for maneuver target tracking显示文摘Square-root cubature Kalman filter (SCKF) is more effective for nonlinear state estimation than an unscented Kalman filter.In this paper,we study the design of nonlinear filters based on SCKF for the system with one step noise correlation and abrupt state change.First,we give the SCKF that deals with the one step correlation between process and measurement noises,SCKF-CN in short.Second,we introduce the idea of a strong tracking filter to construct the adaptive square-root factor of the prediction error covariance with a fading factor,which makes SCKF-CN obtain outstanding tracking performance to the system with target maneuver or abrupt state change.Accordingly,the tracking performance of SCKF is greatly improved.A universal nonlinear estimator is proposed,which can not only deal with the conventional nonlinear filter problem with high dimensionality and correlated noises,but also achieve an excellent strong tracking performance towards the abrupt change of target state.Three simulation examples with a bearings-only tracking system are illustrated to verify the efficiency of the proposed algorithms.Quan-bo GE Wen-bin LI Cheng-lin WEN 2011Journal of Zhejiang University-Science C(Computers and Electronics)2011,12,8:20
2A new algorithm based on the proximity principle for the virtual network embedding problem显示文摘The virtual network embedding/mapping problem is a core issue of network virtualization. It is concerned mainly with how to map virtual network requests to the substrate network efficiently. There are two steps in this problem: node mapping and link mapping. Current studies mainly focus on developing heuristic algorithms, since both steps are computationally intractable. In this paper, we propose a new algorithm based on the proximity principle, which considers the distance factor besides the capacity factor in the node mapping step. Thus, the two steps of the embedding problem can be better integrated and the substrate network resource can be used more efficiently. Simulation results show that the new algorithm greatly enhances the performance of the revenue/cost (R/C) ratio, acceptance ratio, and runtime of the embedding problem.Jiang LIU Tao HUANG Jian-ya CHEN Yun-jie LIU 2011Journal of Zhejiang University-Science C(Computers and Electronics)2011,12,11:15
3Applying gravitational search algorithm in the QoS-based Web service selection problem显示文摘With the growing use of service-oriented architecture for designing next generation software systems,the service composition problem and its execution complexity have become even more important in responding to different user requests.The gravitational search algorithm is one of the latest heuristic algorithms.It has a number of distinguishing features,such as rapid convergence,lower memory usage,and the use of particular parameters,for instance,the distance between the solutions.In this paper,we propose a model for the optimization of the Web service composition problem based on qualitative measures and the gravitational search algorithm.To determine the efficacy of this proposed model we solve the problem with the particle swarm optimization algorithm for comparison.Simulation results show that the gravitational search algorithm has a high potential and substantial efficiency in finding the best combination of Web services.Bahareh ZIBANEZHAD Kamran ZAMANIFAR Razieh Sadat SADJADY Yousef RASTEGARI 2011Journal of Zhejiang University-Science C(Computers and Electronics)2011,12,9:13
4Finger vein recognition using weighted local binary pattern code based on a support vector machine显示文摘Finger vein recognition is a biometric technique which identifies individuals using their unique finger vein patterns. It is reported to have a high accuracy and rapid processing speed. In addition, it is impossible to steal a vein pattern located inside the finger. We propose a new identification method of finger vascular patterns using a weighted local binary pattern (LBP) and support vector machine (SVM). This research is novel in the following three ways. First, holistic codes are extracted through the LBP method without using a vein detection procedure. This reduces the processing time and the complexities in detecting finger vein patterns. Second, we classify the local areas from which the LBP codes are extracted into three categories based on the SVM classifier: local areas that include a large amount (LA), a medium amount (MA), and a small amount (SA) of vein patterns. Third, different weights are assigned to the extracted LBP code according to the local area type (LA, MA, and SA) from which the LBP codes were extracted. The optimal weights are determined empirically in terms of the accuracy of the finger vein recognition. Experimental results show that our equal error rate (EER) is significantly lower compared to that without the proposed method or using a conventional method.Hyeon Chang LEE Byung Jun KANG Eui Chul LEE Kang Ryoung PARK 2010Journal of Zhejiang University-Science C(Computers and Electronics)2010,11,7:13
5Driving intention recognition and behaviour prediction based on a double-layer hidden Markov model显示文摘We propose a model structure with a double-layer hidden Markov model (HMM) to recognise driving intention and predict driving behaviour. The upper-layer multi-dimensional discrete HMM (MDHMM) in the double-layer HMM represents driving intention in a combined working case, constructed according to the driving behaviours in certain single working cases in the lower-layer multi-dimensional Gaussian HMM (MGHMM). The driving behaviours are recognised by manoeuvring the signals of the driver and vehicle state information, and the recognised results are sent to the upper-layer HMM to recognise driving intentions. Also, driving behaviours in the near future are predicted using the likelihood-maximum method. A real-time driving simulator test on the combined working cases showed that the double-layer HMM can recognise driving intention and predict driving behaviour accurately and efficiently. As a result, the model provides the basis for pre-warning and intervention of danger and improving comfort performance.Lei HE Chang-fu ZONG Chang WANG 2012Journal of Zhejiang University-Science C(Computers and Electronics)2012,13,3:13
6Measurement of wireless pressure sensors fabricated in high temperature co-fired ceramic MEMS technology显示文摘High temperature co-fired ceramics(HTCCs) have wide applications with stable mechanical properties,but they have not yet been used to fabricate sensors.By introducing the wireless telemetric sensor system and ceramic structure embedding a pressure-deformable cavity,the designed sensors made from HTCC materials(zirconia and 96% alumina) are fabricated,and their capacities for the pressure measurement are tested using a wireless interrogation method.Using the fabricated sensor,a study is conducted to measure the atmospheric pressure in a sealed vessel.The experimental sensitivity of the device is 2 Hz/Pa of zirconia and 1.08 Hz/Pa of alumina below 0.5 MPa with a readout distance of 2.5 cm.The described sensor technology can be applied for monitoring of atmospheric pressure to evaluate important component parameters in harsh environments.Ji-jun XIONG Shi-jun ZHENG Ying-ping HONG Jun LI Ying-lin WANG Wei WANG Qiu-lin TAN 2013Journal of Zhejiang University-Science C(Computers and Electronics)2013,14,4:13
7Design and analysis of an underwater inductive coupling power transfer system for autonomous underwater vehicle docking applications显示文摘We develop a new kind of underwater inductive coupling power transfer(ICPT)system to evaluate wireless power transfer in autonomous underwater vehicle(AUV)docking applications.Parameters that determine the performance of the system are systematically analyzed through mathematical methods.A circuit simulation model and a finite element analysis(FEA)simulation model are developed to study the power losses of the system,including copper loss in coils,semiconductor loss in circuits,and eddy current loss in transmission media.The characteristics of the power losses can provide guidelines to improve the efficiency of ICPT systems.Calculation results and simulation results are validated by relevant experiments of the prototype system.The output power of the prototype system is up to 45 W and the efficiency is up to 0.84.The preliminary results indicate that the efficiency will increase as the transmission power is raised by increasing the input voltage.When the output power reaches 500 W,the efficiency is expected to exceed 0.94.The efficiency can be further improved by choosing proper semiconductors and coils.The analysis methods prove effective in predicting the performance of similar ICPT systems and should be useful in designing new systems.Jian-guang SHI De-jun LI Can-jun YANG 2014Journal of Zhejiang University-Science C(Computers and Electronics)2014,15,1:13
8Clustering-based hyperspectral band selection using sparse nonnegative matrix factorization显示文摘Hyperspectral imagery generally contains a very large amount of data due to hundreds of spectral bands.Band selection is often applied firstly to reduce computational cost and facilitate subsequent tasks such as land-cover classification and higher level image analysis.In this paper,we propose a new band selection algorithm using sparse nonnegative matrix factorization (sparse NMF).Though acting as a clustering method for band selection,sparse NMF need not consider the distance metric between different spectral bands,which is often the key step for most common clustering-based band selection methods.By imposing sparsity on the coefficient matrix,the bands' clustering assignments can be easily indicated through the largest entry in each column of the matrix.Experimental results showed that sparse NMF provides considerable insight into the clustering-based band selection problem and the selected bands are good for land-cover classification.Ji-ming LI 1,2,Yun-tao QIAN 1 (1 School of Computer Science and Technology,Zhejiang University,Hangzhou 310027,China) (2 Zhejiang Police College,Hangzhou 310053,China) 2011Journal of Zhejiang University-Science C(Computers and Electronics)2011,12,7:12
9Improving the real-time performance of Ethernet for plant automation(EPA) based industrial networks显示文摘Real-time Ethernet(RTE) control systems with critical real-time requirements are called fast real-time(FRT) systems.To improve the real-time performance of Ethernet for plant automation(EPA),we propose an EPA-FRT scheme.The minimum macrocycle of EPA networks is reduced by redefining the EPA network frame format,and the synchronization process is modified to acquire higher accuracy.A multi-segmented topology with a scheduling scheme is introduced to increase effective bandwidth utilization and reduce protocol overheads,and thus to shorten the communication cycle significantly.Performance analysis and practical tests on a prototype system show the effectiveness of the proposed scheme,which achieves the best performance at small periodic payload in large scale systems.Li LU Dong-qin FENG Jian CHU 2013Journal of Zhejiang University-Science C(Computers and Electronics)2013,14,6:12
10A deep learning approach to the classification of 3D CAD models显示文摘Model classification is essential to the management and reuse of 3D CAD models.Manual model classification is laborious and error prone.At the same time,the automatic classification methods are scarce due to the intrinsic complexity of 3D CAD models.In this paper,we propose an automatic 3D CAD model classification approach based on deep neural networks.According to prior knowledge of the CAD domain,features are selected and extracted from 3D CAD models first,and then preprocessed as high dimensional input vectors for category recognition.By analogy with the thinking process of engineers,a deep neural network classifier for 3D CAD models is constructed with the aid of deep learning techniques.To obtain an optimal solution,multiple strategies are appropriately chosen and applied in the training phase,which makes our classifier achieve better performance.We demonstrate the efficiency and effectiveness of our approach through experiments on 3D CAD model datasets.Fei-wei QIN Lu-ye LI Shu-ming GAO Xiao-ling YANG Xiang CHEN 2014Journal of Zhejiang University-Science C(Computers and Electronics)2014,15,2:12
11Knowledge extraction from Chinese wiki encyclopedias显示文摘The vision of the Semantic Web is to build a 'Web of data' that enables machines to understand the semantics of information on the Web.The Linked Open Data(LOD) project encourages people and organizations to publish various open data sets as Resource Description Framework(RDF) on the Web,which promotes the development of the Semantic Web.Among various LOD datasets,DBpedia has proved a successful structured knowledge base,and has become the central interlinking-hub of the Web of data in English.However,in the Chinese language,there is little linked data published and linked to DBpedia.This hinders the structured knowledge sharing of both Chinese and cross-lingual resources.This paper deals with an approach for building a large-scale Chinese structured knowledge base from Chinese wiki resources,including Hudong and Baidu Baike.The proposed approach first builds an ontology based on the wiki category system and infoboxes,and then extracts instances from wiki articles.Using Hudong as our source,our approach builds an ontology containing 19 542 concepts and 2381 properties.802 593 instances are extracted and described using the concepts and properties in the extracted ontology and 62 679 of them are linked to equivalent instances in DBpedia.As from Baidu Baike,our approach builds an ontology containing 299 concepts,37 object properties,and 5590 data type properties.1 319 703 instances are extracted from Baidu Baike,and 84 343 of them are linked to instances in DBpedia.We provide RDF dumps and SPARQL endpoint to access the established Chinese knowledge bases.The knowledge bases built using our approach can be used not only in Chinese linked data building,but also in many useful applications of large-scale knowledge bases,such as question-answering and semantic search.Zhi-chun WANG Zhi-gang WANG Juan-zi LI Jeff Z.PAN 2012Journal of Zhejiang University-Science C(Computers and Electronics)2012,13,4:11
12Multi-objective robot motion planning using a particle swarm optimization model显示文摘Two new heuristic models are developed for motion planning of point robots in known environments.The first model is a combination of an improved particle swarm optimization (PSO) algorithm used as a global planner and the probabilistic roadmap (PRM) method acting as a local obstacle avoidance planner.For the PSO component,new improvements are proposed in initial particle generation,the weighting mechanism,and position-and velocity-updating processes.Moreover,two objective functions which aim to minimize the path length and oscillations,govern the robot’s movements towards its goal.The PSO and PRM components are further intertwined by incorporating the best PSO particles into the randomly generated PRM.The second model combines a genetic algorithm component with the PRM method.In this model,new specific selection,mutation,and crossover operators are designed to evolve the population of discrete particles located in continuous space.Thorough comparisons of the developed models with each other,and against the standard PRM method,show the advantages of the PSO method.Ellips MASEHIAN Davoud SEDIGHIZADEH 2010Journal of Zhejiang University-Science C(Computers and Electronics)2010,11,8:11
13Efficient revocation in ciphertext-policy attribute-based encryption based cryptographic cloud storage显示文摘It is secure for customers to store and share their sensitive data in the cryptographic cloud storage.However,the revocation operation is a sure performance killer in the cryptographic access control system.To optimize the revocation procedure,we present a new efficient revocation scheme which is efficient,secure,and unassisted.In this scheme,the original data are first divided into a number of slices,and then published to the cloud storage.When a revocation occurs,the data owner needs only to retrieve one slice,and re-encrypt and re-publish it.Thus,the revocation process is accelerated by affecting only one slice instead of the whole data.We have applied the efficient revocation scheme to the ciphertext-policy attribute-based encryption(CP-ABE) based cryptographic cloud storage.The security analysis shows that our scheme is computationally secure.The theoretically evaluated and experimentally measured performance results show that the efficient revocation scheme can reduce the data owner's workload if the revocation occurs frequently.Yong CHENG Zhi-ying WANG Jun MA Jiang-jiang WU Song-zhu MEI Jiang-chun REN 2013Journal of Zhejiang University-Science C(Computers and Electronics)2013,14,2:11
14Intelligent optimization of seam-line finding for orthophoto mosaicking with LiDAR point clouds显示文摘A detailed study was carried out to find optimal seam-lines for mosaicking of images acquired by an airborne light detection and ranging (LiDAR) system.High ground objects labeled as obstacles can be identified by delineating black holes from filtered point clouds obtained by filtering the raw laser scanning dataset.An innovative A algorithm is proposed that can automatically make the seam-lines keep away from these obstacles in the registered images.This method can intelligently optimize the selection of seam-lines and improve the quality of orthophotos.A simulated grid image was first used to analyze the effect of different heuristic functions on path planning.Three subsets of LiDAR data from Xi'an,Dunhuang,and Changyang in Northwest China were obtained.A quantitative method including pixel intensity,hue,and texture was used.With our proposed method,9.4%,8.7%,and 9.8% improvements were achieved in Dunhuang,Xi'an,and Changyang,respectively.Hong-chao MA Jie SUN 2011Journal of Zhejiang University-Science C(Computers and Electronics)2011,12,5:10
15Detection of quantization index modulation steganography in G.723.1 bit stream based on quantization index sequence analysis显示文摘This paper presents a method to detect the quantization index modulation(QIM) steganography in G.723.1 bit stream.We show that the distribution of each quantization index(codeword) in the quantization index sequence has unbalanced and correlated characteristics.We present the designs of statistical models to extract the quantitative feature vectors of these characteristics.Combining the extracted vectors with the support vector machine,we build the classifier for detecting the QIM steganography in G.723.1 bit stream.The experiment shows that the method has far better performance than the existing blind detection method which extracts the feature vector in an uncompressed domain.The recall and precision of our method are all more than 90% even for a compressed bit stream duration as low as 3.6 s.Song-bin LI Huai-zhou TAO Yong-feng HUANG 2012Journal of Zhejiang University-Science C(Computers and Electronics)2012,13,8:10
16New separation algorithm for touching grain kernels based on contour segments and ellipse fitting显示文摘A new separation algorithm based on contour segments and ellipse fitting is proposed to separate the ellipse-like touching grain kernels in digital images.The image is filtered and converted into a binary image first.Then the contour of touching grain kernels is extracted and divided into contour segments (CS) with the concave points on it.The next step is to merge the contour segments,which is the main contribution of this work.The distance measurement (DM) and deviation error measurement (DEM) are proposed to test whether the contour segments pertain to the same kernel or not.If they pass the measurement and judgment,they are merged as a new segment.Finally with these newly merged contour segments,the ellipses are fitted as the representative ellipses for touching kernels.To verify the proposed algorithm,six different kinds of Korean grains were tested.Experimental results showed that the proposed method is efficient and accurate for the separation of the touching grain kernels.Lei YAN Cheol-Woo PARK Sang-Ryong LEE Choon-Young LEE 2011Journal of Zhejiang University-Science C(Computers and Electronics)2011,12,1:9
17Design considerations for electromagnetic couplers in contactless power transmission systems for deep-sea applications显示文摘In underwater applications of contactless power transmission(CLPT) systems,high pressure and noncoaxial operations will change the parameters of electromagnetic(EM) couplers.As a result,the system will divert from its optimum performance.Using a reluctance modeling method,we investigated the gap effects on the EM coupler in deep-sea environment.Calculations and measurements were performed to analyze the influence of high pressure and noncoaxial alignments on the coupler.It was shown that it is useful to set a relatively large gap between cores to reduce the influence of pressure.Experiments were carried out to verify the transferring capacity of the designed coupler and system for a fixed frequency.The results showed that an EM coupler with a large gap can serve a stable and efficient power transmission for the CLPT system.The designed system can transfer more than 400 W electrical power with a 2-mm gap in the EM coupler,and the efficiency was up to 90% coaxially and 87% non-coaxially in 40 MPa salt water.Finally,a mechanical layout of a 400 W EM coupler for the underwater application in 4000-m deep sea was proposed.Ze-song LI De-jun LI Lin LIN Ying CHEN 2010Journal of Zhejiang University-Science C(Computers and Electronics)2010,11,10:9
18Triangular domain extension of linear Bernstein-like trigonometric polynomial basis显示文摘In computer aided geometric design(CAGD),the Bernstein-Bézier system for polynomial space including the triangular domain is an important tool for modeling free form shapes.The Bernstein-like bases for other spaces(trigonometric polynomial,hyperbolic polynomial,or blended space) has also been studied.However,none of them was extended to the triangular domain.In this paper,we extend the linear trigonometric polynomial basis to the triangular domain and obtain a new Bernstein-like basis,which is linearly independent and satisfies positivity,partition of unity,symmetry,and boundary represen-tation.We prove some properties of the corresponding surfaces,including differentiation,subdivision,convex hull,and so forth.Some applications are shown.Wan-qiang SHEN Guo-zhao WANG 2010Journal of Zhejiang University-Science C(Computers and Electronics)2010,11,5:7
19Development of a direct current power system for a multi-node cabled ocean observatory system显示文摘Due to the shortage of suitable research methods for real-time and long-term observation of oceans,an innovative approach that can provide abundant power and wide bandwidth is being developed worldwide for undersea instruments.In this paper,we develop a direct current(DC) power system which is applied to a multi-node cabled ocean observatory system named ZERO(Zhejiang University Experimental and Research Observatory).The system addresses significant issues ranging from terrestrial facility to subsea infrastructure,and focuses on using appropriate methods to deal with several key challenges,including delivery,conversion,distribution,and management of power,and heat dissipation in pressure vessels.A basic laboratory platform consisting of a shore station,a primary node in a water tank,and a secondary node in a deep-sea simulation chamber under 42 MPa pressure was built and fully tested.An improved secondary node was deployed in Monterey Bay in California for a deep-sea trial.An 11-day laboratory test and a half-year sea trial proved that the DC power system based on our proposed methods is viable for the underwater multi-node observatory system.Yan-hu CHEN Can-jun YANG De-jun LI Bo JIN Ying CHEN 2012Journal of Zhejiang University-Science C(Computers and Electronics)2012,13,8:7
20Short text classification based on strong feature thesaurus显示文摘Data sparseness, the evident characteristic of short text, has always been regarded as the main cause of the low accuracy in the classification of short texts using statistical methods. Intensive research has been conducted in this area during the past decade. However, most researchers failed to notice that ignoring the semantic importance of certain feature terms might also contribute to low classification accuracy. In this paper we present a new method to tackle the problem by building a strong feature thesaurus (SFT) based on latent Dirichlet allocation (LDA) and information gain (IG) models. By giving larger weights to feature terms in SFT, the classification accuracy can be improved. Specifically, our method appeared to be more effective with more detailed classification. Experiments in two short text datasets demonstrate that our approach achieved improvement compared with the state-of-the-art methods including support vector machine (SVM) and Nave Bayes Multinomial.Bing-kun WANG Yong-feng HUANG Wan-xia YANG Xing LI 2012Journal of Zhejiang University-Science C(Computers and Electronics)2012,13,9:7
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