最新刊期
卷 47 ， 期 9 ， 2019
- 摘要：In order to balance the exploration and exploitation of particle swarm optimization, this paper proposes a hybrid mean center opposition-based learning particle swarm optimization. The algorithm performs greedy selection on the mean center of all particles and some high-quality particles respectively, and the obtained hybrid mean center will search the region in detail where the particles are located. At the same time, the hybrid mean center is using opposition-based learning, so that the particles can explore more new regions. The proposed algorithm are compared with the latest improved particle swarm optimization, artificial bee colony algorithm and difference algorithm in various test function sets, and the results verify the effectiveness of the hybrid mean center opposition-based learning and the overall optimization performance of the algorithm is stronger.关键词：global optimization;hybrid mean center;opposition-based learning;particle swarm optimization224|470|15更新时间：2025-07-16
- 摘要：A blind range-direction estimation method is proposed for suppressing the mainlobe smart jamming (MSJ). The proposed method can effectively suppress the MSJ and estimate the direction-distance parameter of the target echo. Firstly, the target and MSJ is separated by the blind source separation (BSS) algorithm with the element data, and the estimation of the mixed matrix can be obtained simultaneously. Secondly, according to the prior information that the MSJ contains multiple false target echoes in a certain direction, while the real target just contains one echo, we can determine the separated channel which contains the real target. In this way, the real target distance parameter can be estimated. Finally, the mixed matrix column vector of the real target is obtained by the above judgement, which can be adopted to estimate the direction parameter of the real target.Simulation results show that the proposed method can effectively suppress two MSJs at least, and obtain good range-direction estimation performance at the same time. In addition, we analyze the effects of signal-to-noise ratio (SNR), interference-to-noise ratio (INR), the angle between the target and MSJ, and the MSJ number on the performance of the proposed method. The corresponding boundary conditions are also given.关键词：blind source separation (BSS);mainlobe smart jamming (MSJ);range-direction estimation;anti-jamming78|209|3更新时间：2025-07-16
- 摘要：Aiming at the nonlinear state estimation problem with heavy-tailed process measurement noise and randomly delayed measurements, this paper deduces a new robust student's t filter framework by taking into one-step random delay characteristics and heavy-tailed characteristics of process noise and measurement noise account fully. Meanwhile, this paper proposes a new robust Student's t-based stochastic cubature filter(RSTCF)by approximately calculating the Student's t weight integral using stochastic Student's t-spherical radial cubature rule. Firstly, this paper uses a set of stochastic sequences obeying the Bernoulli distribution to describe the possible one-step random delay phenomenon in the system,what's more,this paper also uses the student's t distribution to characterize the heavy-tailed characteristics of the process noise and measurement noise. Secondly, it's theoretically proved that the robust Student's t filter automatically will be reduced to a standard nonlinear Gaussian approximation filter when the degrees of freedom in the posterior probability density function of the state and measurement noise are increasing continuously and randomly delay probability is equal to zero. Finally, this paper presentes a new robust Student's t-based stochastic cubature filter by use of stochastic Student's t-spherical radial cubature rule. The effectiveness and superiority of the filter are verified by the coordinated turn maneuvers model.关键词：randomly delay;heavy-tailed noises;student's t weighted integrals;Bernoulli distribution;moment matching method;nonlinear estimation139|233|2更新时间：2025-07-16
- 摘要：Cross-lingual entity alignment aims to find entities in knowledge graphs of different languages that point to the same objects in the real world. Traditional cross-lingual entity alignment methods usually rely solely on the internal structure information of the knowledge graph, but in fact entity description information provided by some knowledge graphs can also be utilized. This paper proposes an entity alignment model that combines the internal structure information of the knowledge graph with the entity description information for cross-lingual entity alignment. The model first finds the entity pairs that may be aligned by training the knowledge embeddings based on the structure information of the knowledge graph,and then uses entity descriptions to select the final aligned entity pairs based on the improved optimal alignment similarity model. Finally, the model iteratively align the first two steps to find more aligned entity pairs until the end of the training. The experimental results show that compared with the benchmark algorithms, the proposed model can achieve relatively good results in cross-lingual entity alignment task.关键词：cross-lingual entity alignment;knowledge embeddings;cross-lingual description similarity261|346|2更新时间：2025-07-16
- 摘要：Collaborative filtering, as the core technology of recommendation systems, is currently facing the sparsity problem of rating data. This can be effectively solved through integrating item text information. However, current methods focus on extracting the one-dimensional features of the text, neglecting its multidimensional semantic features. Digging deeply into the multidimensional semantic features of the text can improve the recommendations. To help achieve this goal,a probabilistic matrix factorization model based on multidimensional semantic representation learning is proposed in the present study. The model uses a capsule network to mine the multidimensional semantic features of the text, and then integrates it into the probabilistic matrix decomposition framework using the regularization method to reveal hidden features linking users and items. Experimental results show that the proposed model has higher prediction accuracy.关键词：collaborative filtering;probabilistic matrix factorization;capsule network;multidimensional semantic features;regularization;hybrid recommendation212|304|8更新时间：2025-07-16
- 摘要：Based on the observability analysis of the measurement model under the modern control theory,this paper proposes the observability problem of the absolute clock state measurement model. It is inspired by measured state vector space and state vector algorithm, and transformed into the isomorphic mapping principle of vector space essentially. It establishes the minimum mean square error (MMSE) observable decoupling measurement model under equivalent transformation with basic measurement unit (BMU). This method reveals the essence of symmetric measurement performance under two-way message exchange,and realizes Kalman filtering algorithm for clock state tracking under the necessary conditions that the measurement model satisfies the observability. The proposed algorithm does not depend on the optimized initial point setting, the initial point selection is robust,and it is also robust to changes in network connectivity. The simulation results show that the observable measurement model can achieve scale expansion, and the proposed algorithm has local and global uniform of MMSE measurement performance, which is close to the boundary of the Bayesian Cramer-Rao lower bound (CRLB) measurement performance.关键词：wireless sensor network;absolute clock synchronization;observability;linear transformation215|217|2更新时间：2025-07-16
- 摘要：Quantum full adder is the basic elements of quantum computers, in order to reduce the energy loss and cut the construction cost and the difficulty of physical realization. The paper proposes a new type of n-bit quantum full adder which uses 3n CNOT(Controlled NOT) Gates and 2n-1 Toffoli gates to implement n-bit quantum addition and subtraction, adopts the carry look-ahead mode without carry input,and judges the carry of addition and positive and negative sign of subtraction with the highest overflow mark bit that does not participate in the calculation of high and low bit, which does not increase time delay of the circuit and suits for n-bit quantum parallel operation. The simulation operation with random number of 4,8,16 and 32 digits verifies the correctness of the full adder separately. The low quantum cost and simple circuit structure of the quantum full adder is helpful to improve the size and integration of integrated circuits.关键词：reversible logic circuit;quantum full adder;carry look-ahead;quantum cost;circuit energy consumption;quantum computer214|274|2更新时间：2025-07-16
- 摘要：Approximate computing is a novel way in logic circuit design which offers the savings of the power,area and delay at cost of reduced accuracy. This paper focused on the fixed-polarity Reed-Muller(RM) functions area optimization by using approximate computing technique which is different from those used in traditional Boolean functions optimization in term of the characteristic of "XOR" in RM functions. The proposed algorithm mainly consists of the method of the error rate computing of RM functions using disjointed products and the approach of the approximate FPRM functions searching for less area under the given error rate constraint. The proposed algorithm is tested under MCNC (Microelectronics Center of North Carolina) benchmarks.The experimental results show that it can deal with the large function with 199 inputs. And by using the approximate computing technique,the average area can be reduced by 62.0% with the average error rate of 5.7%. The proposed approximate computing technique based algorithm is also beneficial for dynamic power saving and has little effect on the delay while optimizing the area of a circuit.关键词：approximate computing;Reed-Muller functions;fixed-polarity;logic optimization62|219|1更新时间：2025-07-16
- 摘要：A type of nonlinear prediction model for speech signals based on second-order Volterra series is put forward. In order to overcome some intrinsic shortcomings caused by using the classic least mean square (LMS) algorithm to update Volterra model kernel coefficients, a dissipative uniform particle swarm optimization (DUPSO) algorithm is applied to obtain the kernel coefficients and then a DUPSO-SOVF prediction model can be constructed. A DUPSO-SOVF prediction model with hidden phase space is constructed by dynamically obtaining parameters of embedding dimension and time delay in the process of solving model kernel coefficients rather than using traditional phase space reconstruction process.On the purpose to reduce model complexity,the key model kernels are extracted within the margin of the allowable error and the model kernels are then reduced, and the reduced parameter DUPSO-SOVF (RPSOVF) prediction model is proposed. Simulation results for samples of English phonemes,words and phrases show that, the DUPSO-SOVF model with hidden phase space can accurately calculate parameters of embedding dimension and delay time of phase space reconstruction; both of the DUPSO-SOVF model and the DUPSO-RPSOVF model exhibit higher prediction accuracy on single frame and multi-frame speech signal than PSO-SOVF and LMS-SOVF models. Also, the two proposed models can better reflect trends and regularities of the speech signal series and meet requirements for speech signal prediction.关键词：speech signal;prediction;Volterra model;DUPSO algorithm;hidden phase space reconstruction50|167|1更新时间：2025-07-16
- 摘要：A new constant false alarm rate (CFAR) detection analysis method based on multilook polarimetric whitening filter (MPWF) is proposed in polarimetric synthetic aperture radar (POLSAR) imagery when the clutter obeys Beta distributed texture hypothesis. Firstly, the texture variable in the product model obeys Beta distribution is assumed,and the probability density function (PDF) of MPWF output is derived. Then, the analytical formula of probability of false alarm (PFA) is obtained by integrating probability density function (PDF), and the corresponding CFAR process is designed.Finally,a log-cumulants estimation method based on MPWF is proposed to estimate the texture parameters u and v of Beta distribution. The effectiveness of the new method is verified by simulation data and measured data. Simulation results show that Beta distribution has better goodness of fit on some regions in POLSAR images ,and the new method has better CFAR performance compared with the existing methods. The embedded and measured data also show that the new method has better detection performances than the existing methods.关键词：polarimetric synthetic aperture radar;constant false alarm rate;beta distribution;polarimetric whitening filter;ship detection49|123|3更新时间：2025-07-16
- 摘要：In order to verify the confidence of the blind analysis result of the LFM/BPSK (Linear Frequency Modulation/Binary Phase Shift Keying) hybrid modulation signals by using the maximum value of the correlation spectrum, a simple likelihood ratio algorithm based on extreme value theory is formulated in this paper, which can solve the problem caused by the complexity of the probability of the maximum statistic of the correlation spectrum when creating the likelihood ratio test. By replacing the asymptotic distribution of the exact distribution of the maximum statistic and using the NP criterion, the decision statistic and its corresponding threshold is derived. The asymptotic distribution of the maximum statistic under the two hypotheses are provided. The simulations show that the performance of the proposed algorithm is similar to the constant false alarm based algorithm, and is superior to the two goodness of fit test based algorithms that are formulated by the group extreme value and the peak over threshold models respectively.关键词：credibility evaluation;LFM/BPSK hybrid modulation;generalized extreme value distribution;generalized Pareto distribution47|151|2更新时间：2025-07-16
- 摘要：To solve the problem about structure learning of optimal Bayesian network, this paper proposes dynamic programming constrained with Markov blanket (DPCMB), which uses Markov blanket calculated by incremental association Markov blanket (IAMB) to reduce the number of scoring calculations in dynamic programming. We research on the effect of the significance value in IAMB on the performance indicators of DPCMB algorithm, and give reasonable suggestions for adjusting the significance value. Experimental results show that the DPCMB algorithm can adjust the significance value so that the accuracy of the algorithm is comparable to that of the DP algorithm, and running time, score calculation times,and memory requirements of the algorithm are greatly reduced.关键词：Bayesian network structure learning;dynamic programming;Markov blanket;IAMB67|274|3更新时间：2025-07-16
- 摘要：For the issue of low accuracy of phase difference estimation affected by the noise under the condition of frequency mismatch, an unbiased adaptive phase difference estimation method in the presence of frequency mismatch is proposed, which could improve the accuracy of phase difference estimation and enhance the ability of anti-noise. Therefore, firstly the expansion parameters of two sinusoidal signals are adaptive estimated, which is used to estimate the phase difference between two sinusoidal signals. Secondly, the deviation analysis of phase difference estimation is carried out by the expansion of Taylor series, the unbiased phase difference estimation with frequency mismatch is proved, and the performance of steady-state for phase difference estimation are also presented. Consequently, the phase difference estimation results of different methods are compared, the effect by different parameters are discussed, and the calculated results are provided to confirm the effectiveness and correctness of the proposed method.关键词：phase difference estimation;frequency mismatch;unbiased;performance analysis30|163|0更新时间：2025-07-16
- 摘要：Since pirated Android applications (APPs for short) usually maintain a similar user experience to original APPs, a fast APP similarity detection approach based on resource signature has been proposed. In order to determine the similarity of a pair of APP, the approach calculates the Jaccard coefficient of resource signature sets of them because a set of resource signatures can be treated as a set of strings. With the help of the MinHash and LSH (Locality Sensitive Hashing) algorithm, it can avoid the traversal of all APP pairs by selecting candidate pairs from the APP set and verifying them at last.Because the procedure of selecting candidate pairs excludes a large number of APP pairs with lower similarity, this approach can significantly improve the detection speed of APP similarity. The experimental results show that the detection speed of this approach is about 30 times higher than the existing approach FSquaDRA while the detection result is almost identical.关键词：APP similarity;resource signature;MinHash;LSH;Jaccard coefficient43|136|1更新时间：2025-07-16
- 摘要：In recent years, a wide variety of bursty events have been occurring frequently in many fields,impacting both the stability and the development of our society. This paper proposes an event detection model based on multiple word features, which is intended to detect bursty events in the massive microblog data. The model will assist decision-makers to monitor microblogs and guide public opinions and will minimize the negative effect of bursty events to society. Firstly, the model slices the microblog data according to the time information. In each time window, the word frequency feature, the topic tag feature and the word frequency growth rate feature of each word are calculated separately. Then, the D-S evidence theory and the analytic hierarchy process are utilized to determine each word's feature weights, which are then merged to obtain the bursty feature value of the word. Words with large bursty feature value are selected to form the bursty feature word set and to construct a coupling degree matrix of bursty feature word set based on co-occurrence degree and tightness. Finally, the coupling degree matrix is used as the input of the hierarchical agglomerative clustering algorithm to generate a binary tree with bursty words being leaf nodes, and the internal similarity binary tree pruning algorithm is used to divide the clustering results.In this way, the detection of the corresponding time window's bursty events can be realized. The experimental results show that the event detection model based on bursty words has the best effect when the intra-cluster similarity threshold is 1.1, the correct rate is as high as 0.8462, the recall rate reaches 0.8684, and the F value is 0.8571, indicating the effectiveness of the proposed method.关键词：microblog;bursty events;bursty feature words;D-S evidence theory;hierarchical agglomerative clustering60|188|3更新时间：2025-07-16
- 摘要：Heterogeneous network similarity learning is to analyze the degree of correlation between two different types of objects. Different types of objects have different degrees of importance in heterogeneous networks, and play different roles in the similarity learning process.This paper proposes a node influence based similarity measure method (NISim) heterogeneous information network. This method not only considers the link structure in network but also keeps the semantic information in heterogeneous networks. Also, this method distinguishes the effect to heterogeneous network brought by different types of nodes. In heterogeneous network, the heuristic rules are used to distinguish and quantify the influence weight of different types of nodes. In addition, the link structure in network and the semantic relationship are combined to solve the problem of improving similarity learning accuracy. Experimental results show that this method can measure the similarity between different types of nodes effectively. It can be applied in different fields such as network search, recommendation system and knowledge graph construction and so on.关键词：data mining;heterogeneous network;recommended system;knowledge graph;network search;node influence;link structure;semantic relationship87|244|3更新时间：2025-07-16
- 摘要：Aiming at the problem of low efficiency of pipelined scheduling in system of periodic query gated service, this paper proposes a systematic service resource scheduling strategy based on parallel optimization gated service polling control. Firstly, the queuing system and its mathematical model are constructed. Moreover, after deriving the partial derivative of the probability generating function of the system state variables, the first and second order partial differential equations are solved. Finally the complete mathematical analytic expressions of the system performance parameters are derived. In this paper,the system is further verified by computer simulation experiments, and it is found that the statistical analysis results are consistent with the theoretical analysis results. The performance analysis shows that the queuing length and waiting delay characteristics of the polling system have been greatly improved, which can better adapt to the service requirements of delay sensitive data in dense data environment.关键词：systematic service scheduling strategy;polling;parallel optimization gated service;mean queue length;mean query cycle;mean waiting delay93|172|7更新时间：2025-07-16
- 摘要：The parametric covariance matrix estimation (PCE) method uses the system parameters to estimate the clutter covariance matrix (CCM). It can greatly improve the performance of space-time adaptive processing (STAP) in nonhomogeneous environment. However, the performance of PCE method is seriously degraded when the system parameter information or clutter distribution is in error. This paper presents a robust parametric covariance matrix estimation based STAP method. First the clutter distribution is estimated by the sparse recovery (SR) and Radon transform. Then a normalized generalized inner product statistic (N-GIP) is proposed to modify the clutter distribution parameters. Finally, the PCE method is utilized to estimate the CCM and the STAP is used to suppress clutter. The simulation experiments and measured data processing results show that the robustness of the proposed method is greatly improved. Compared with the sparse recovery STAP (SR STAP) and forward/backward smoothing STAP (F/B STAP), the filter notches are more accurate and deeper. This benefits the detection of slow targets.关键词：high frequency radar;clutter suppression;space-time adaptive processing;sparse recovery;Radon transform;parameter estimation117|213|1更新时间：2025-07-16
- 摘要：Information geometry based matrix CFAR (Constant False Alarm Rate) detector provides a way to the problem of radar target detection, which mainly consists of the estimation of mean matrix and the calculation of test statistics. The detection performance is closely related to the geometric measures on the matrix manifold. The existing geometric measures are considered from Frobenius norm. By contrast, this paper considers the geometric measure and the estimation of mean matrix by utilizing matrix spectral norm on matrix manifold. The mean matrix estimation is transformed into the optimization problem on the matrix manifold. The approximate mean matrix with low computational complexity is obtained according to the properties of the objective function. In addition, we propose several matrix CFAR detectors based on different mean matrix estimation methods. Finally, the detection power analysis and simulation results show that the detection performance of the proposed methods with lower computational complexity are superior to other existing matrix CFAR detectors. It provides a new effective technique for radar target detection under sea clutter background.关键词：radar target detection;constant false alarm rate (CFAR);sea clutter;information geometry170|206|6更新时间：2025-07-16
- 摘要：Restricted Boltzmann machine (RBM) is a stochastic neural network and probabilistic graphical model, which is one of the most effective models without supervision in deep learning. Focusing on the gradient approximation algorithm insensitivity to the momentum acceleration and recognition effectiveness in RBM, we propose the algorithm based on modified momentum using RBM. When the rule to update the hidden states adopts the probability value instead of sampling a binary value, this calculation method for the RBM gradient approximation leads to the undesirable recognition performance and limited momentum acceleration.Therefore,we modify the updating rule of the hidden bias to avoid these problems.Simultaneously,we use the rapidly ascending momentum method to improve the learning speed in the RBM pre-training phase. An improved slowly descending momentum method is also used in the fine-tuning stage to accurately find the best point, which is far from becoming trapped in poor local optima and improves the classification effect. Through the recognition experiments on MNIST dataset, Extended Yale B and CMU-PIE face dataset, the achieved results show that the proposed algorithm can enhance the computation efficiency and improve the generalization ability of networks. The algorithm not only extends the application fields of RBM, but also provides a new research idea and reference for the application method of deep learning.关键词：deep learning;unsupervised learning;restricted Boltzmann machine;gradient approximation algorithm;Gibbs sampling;momentum acceleration;generalization ability76|207|2更新时间：2025-07-16
- 摘要：Following the idea of separation of control and forwarding, the data forwarding of software-defined WSN (Wireless Sensor Network) is implemented in a flow-based manner. Therefore, nodes behavior during rule updating in software-defined WSN may violate network attribute consistency. Therefore, this paper proposes the concept of per-package forwarding consistency and proves that it can maintain the update consistency of all attributes. On this basis, a rule forwarding consistent update algorithm is proposed by introducing cache nodes and rules to simplify dependencies. The algorithm supports fast parallel updates while satisfying the per-package forwarding consistency. The experimental results show that the algorithm has obvious advantages in the rule cost, update time and communication overhead.关键词：wireless sensor network;software-defined networking;Internet of Things (IoT);software-defined wireless sensor network;network security;rule update;per-package forwarding consistency96|234|1更新时间：2025-07-16
- 摘要：Certificateless signature combines the advantages of identity-based cryptosystem and traditional public-key cryptosystem to solve the problems of complex public key certificate management and key escrow. Wu and Jing proposed a strongly unforgeable certificateless signature scheme whose security does not depend on the ideal random oracle. In this paper, two types of forgery attacks are proposed for the security of this scheme. The analysis results show that this scheme cannot achieve strong unforgeability and is insecure under the "malicious-but-passive" key generation center attack. To enhance the security of this scheme, an improved certificateless signature scheme is presented. The improved scheme is proved to be strongly unforgeable against adaptive chosen-message attacks and can also resist malicious key generation center attacks. In addition, the improved scheme has lower computational overhead and shorter private key length,and can be applied to blockchain, Internet of vehicles, wireless body area network and other fields.关键词：certificateless signature;forgery attack;public key;private key;digital signature;cryptography249|270|2更新时间：2025-07-16
- 摘要：Most of current crop-disease recognition approaches mainly focus on improving the recognition accuracy on public datasets, while ignoring the recognition robustness.When dealing with real-world recognition problem, the actual recognition accuracy of those approach are often unsatisfactory because of noise interference and environmental influence. To address these issues, we propose a high-order residual and parameter-sharing feedback convolutional neural network (HORPSF) for crop-disease recognition. The high-order residual subnetwork is helpful for improving the recognition accuracy of crop disease. The parameter-sharing feedback subnetwork can effectively depress the background noises and enhance the robustness of the model. Extensive experiment results demonstrate that the proposed HORPSF approach significantly outperforms other competing methods in terms of recognition accuracy and robustness, especially demonstrating superior performance when dealing with the real-world examples of crop-disease recognition.关键词：high-order residual (HOR);parameter-sharing feedback (PSF);robustness;crop disease recognition59|210|6更新时间：2025-07-16
- 摘要：The applications, such as video surveillance, backup, and archiving, generate massive storage data, which make the energy consumption of storage devices increase rapidly. S-RAID can reduce the storage energy consumption of above applications significantly. In order to make more disks standby for energy saving, S-RAID prefers to small write. However, performing small write requires additional and equal amount of read operations for generating parity data, and the write performance of S-RAID is decreased. The existing prefetching mechanism mainly implements at the file system level, and cannot sense the read operations generated by small write at RAID level, such as reading old data and reading old parity. So it can not prefetch these old data and old parity data. Therefore, a RAID-level prefetching algorithm for small write of S-RAID is proposed, which is triggered by small write operations and performs at RAID level. It asynchronously prefetches the old data and old parity data required by small writes in large granularity according to the data layout of S-RAID. The write performance of S-RAID can be improved by about 40% without any additional hardware cost.关键词：massive storage;energy conservation;partial parallelism;RAID;data layout56|159|0更新时间：2025-07-16
- 摘要：In order to realize the energy-saving operation of three-phase inverter, a novel three-phase resonant DC(Direct Current) link inverter with soft-switching function is proposed. The auxiliary resonant circuit on the DC side can participate in the commutation process, making the DC link voltage change to zero before the main switches act on the bridge arm. Therefore, the main switches can achieve the zero-voltage soft-switching action, and realize the energy-saving operation of the inverter by reducing the switching loss. The workflows of the circuit are analyzed. The experimental results show that the switching devices are in the state of soft switching. The structure of the auxiliary resonant circuit has reference value for research and development of an energy-saving three-phase inverter.关键词：energy-saving;inverter;auxiliary resonant circuit;soft-switching;switching loss134|251|1更新时间：2025-07-16
- 摘要：Gabor filtering is a well-known feature extraction method, which has been widely studied and applied in the field of machine vision. This paper presents a new multi-directional and multi-scale Gabor feature representation, extraction and its matching algorithm. By using a set of Gabor filters with different scales and different directions to filter an image, the filtered results in each direction are reorganized in the order of the scales and concatenated into a multi-directional and multi-scale Gabor feature. We further propose the concept of cyclic vectors and redefine a similarity measure for multi-directional and multi-scale Gabor features as the maximum similarity value between one feature vector and the corresponding cyclic vectors. Our experimental results show that the proposed descriptor not only has the characteristics of translational invariance, rotational invariance,and scale invariance, but also embody the good feature representation ability and the significant discriminative strength for the local region descriptors in image.关键词：local feature;cyclic vector;multi-directional and multi-scale Gabor features;Gabor filter bank;similarity52|164|0更新时间：2025-07-16
- 摘要：The second order non-autonomous circuit of containing sometime both self-excited and forced components is a mixing oscillation. The whole network can be divided into two components, each of which can give independent phasor or algebraic equation by its own oscillation frequency, and then be solved together.The second order non-autonomous circuits are found by means of the harmonic analysis methods. Concerning the initial assumption of harmonic components, if it fits the physical characteristics of the circuit, the correct real number solution will be obtained. By contrast, the absence of real number solution implies an improper initial assumption. In this case, careful analysis and revise is necessary to reset the initial harmonic components. The nonlinear circuits of coexisting third power and fifth power is discussed in this paper. It possesses very important meaning to explain the rationality of the initial assumption of harmonic components.关键词：non-autonomous circuits;mixing;harmonic analysis;coupling;initial phase angle110|191|0更新时间：2025-07-16
- 摘要：A single-phase full-bridge resonant DC(Direct Current) link soft-switching inverter with the function of improving steady voltage across DC link is proposed to improve the utilization of DC voltage. The electrical energy can be supplemented via the transformer in the auxiliary circuit to the clamp capacitor equivalent to the voltage source on the DC bus so that the steady voltage across DC link is higher than the DC power supply voltage, which improves the fundamental wave amplitude of the output line voltage and DC voltage utilization ratio of the inverter. This paper analyzes the working process of the circuit.The experimental results on the 4kW prototype show that the main switch and auxiliary switch of the inverter can achieve soft-switching. Therefore, the proposed topology has certain reference significance for the development of high-performance resonant DC link inverters.关键词：inverter;soft-switching;transformer;resonance;DC voltage utilization52|161|1更新时间：2025-07-16
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