最新刊期
卷 46 ， 期 5 ， 2018
- 摘要：Compared with the traditional intrusion detection system,the intrusion detection system based on virtual machine introspection has stronger anti-jamming ability.However,the difference between the hardware byte information and the high level semantics leads to the decrease of the versatility and real-time.Aiming to solve this problem,this paper proposes Vlhd,a OS hidden object detection technology based on semantic repair method.Vlhd separates the system into two parts:the offline module and the online module.The online module reconstructs semantic view outside the target virtual machine;the offline module is responsible for the extraction of OS semantic knowledge,and providing semantic services to the online module.Through a variety of rootkit intrusion detection test in various types of Linux OS,we find that Vlhd can detect the objects hidden by rootkits.A single scan time of Vlhd is 34ms,and the performance overhead is 1.1% (scan cycle is set to 8s).关键词：virtualization;hidden detection;rootkit;xen;semantic repair297|455|1更新时间：2025-07-08
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The ε Constrained Multi-objective Decomposition Optimization Algorithm Based on Re-matching Strategy
摘要：Aiming at the problem that unreasonable distribution between weight vector and individual in MOEA/D reduce diversity,the ε constrained multi-objective decomposition optimization algorithm based on re-matching strategy is proposed.Firstly,through theoretical analysis of the chebycheff decomposition strategy,two theorems about diversity and convergence are gained,which could provide a theoretical basis for the research of MOEA/D.Secondly,in order to solve the problem of diversity reduction caused by random assignment of individual to weight vector,the re-matching strategy is presented for reasonably assigning individual to weight vector,and then diversity is improved.Finally,the suggested individual comparison criterion has a good balance between diversity and convergence,and it increases optimization performance.Comparative experiment results with five excellent algorithms show that our algorithm achieves better diversity and convergence,and our algorithm has a certain advantage.209|277|11更新时间：2025-07-08 - 摘要：The method of deep sparse auto-encoder networks has achieved state-of-art performance in the fields of image processing and natural language processing.It's been proved that higher accuracy of deep sparse auto-encoder networks is obtained by the increase of features' number,however,it also leads to a longer training time.In this paper,an optimized sparse auto-encoder networks which based on feature clustering is been presented for both classification accuracy enhancement and training time decreasing.The proposed method first get the number of substantive features by optimizing k-means clustering.Then initialize the network with that number and obtain the substantive features by training again the network.Finally the improvement of feature varieties is achieved by rotation and distortion of the substantive features.In the experiments,the improvement of classification accuracy and reduction of training time is verified by comparing the performance of optimized sparse auto-encoder with normal sparse auto-encoder in the basic dataset MNIST and CMU-PIE.关键词：deep learning;sparse auto-encoder;feature extraction;K-means clustering297|266|6更新时间：2025-07-08
- 摘要：How to assess students' cognitive structure is an important problem in the process of education and teaching.Traditionally,teachers evaluate a student based on their classroom performance and scores,which is lack of efficiency,objectivity,and it is hard to treat anyone equally.To solve this problem,DINA model,which is able to evaluate knowledge proficiency of students,has become a popular Cognitive Diagnosis model with a good interpretation.However,traditional DINA models are all based on small samples.When it comes to large-scale online learning scenario,the calculation will be significantly time-consuming.To address these issues,we first give proof of the convergence of DINA model,and then propose three acceleration methods.To be specific,the first one,called Incremental DINA(I-DINA),can partition the student data into blocks and iterate through the blocks.Then the second one,Maximum-Entropy DINA(ME-DINA),can choose and only access the most powerful students.At last,we combine the advantages of these two methods and propose the last model called Incremental Maximum Entropy DINA(IME-DINA).Extensive experiments on both a real-world dataset and simulation data demonstrate that our models can achieve dozens of acceleration without reducing the effectiveness of DINA Model.关键词：educational data mining;cognitive diagnosis;DINA model;convergence acceleration;expectation maximization algorithm392|326|5更新时间：2025-07-08
- 摘要：Aiming at the problem of usability for traditional two factor authentication (2FA),we propose a low interaction mobile 2FA system in this paper.In our system users only need to enter the usernames and passwords in the browser and press the confirm button on the mobile app for authentication.The average login time for users is no more than 5 seconds.Compared with the current usability enhanced 2FA systems,our system can resist attackers in the same environment and support users to login website with phone browsers.The experimental and analytical results shows the effectiveness of our system.关键词：mobile two-factor authentication (2FA);WiFi fingerprint;device fingerprint161|150|1更新时间：2025-07-08
- 摘要：Skyline query can compute the optimal solution which meets the multiple standards in large-scale dataset.It has been widely applied for multi-objective decisions.Dynamic skyline query,as an important variant of skyline,its result can be dynamically changed with choosing different query points,providing more flexibility when the users make some specified needs.However,dynamic skyline query can return a large number of query results and ignore the directionality of query point and data integrality,making difficult for users to choose.It is necessary to optimize the result set of dynamic skyline,improving the whole data integrality and filtering a large number of redundant data.Focusing on these problems,we propose the augmented dynamic skyline query method based on MapReduce.The algorithm partitions the original data according to dimensional information,parallel computes dynamic skyline points in multiple nodes,optimizes the result set of the traditional dynamic skyline and at the same time provides the more global optimal results for the user to choose.In addition,when the users provide the tolerance of some dimensions,we propose the augmented dynamic skyline query with user tolerance.The algorithm reduces the original dataset according to the user tolerance and reduces the comparison times of intermediate results with improving the accuracy of the result set.The experiment results show that the augmented dynamic skyline query method based on MapReduce is efficient,accurate and scalable.关键词：dynamic skyline query;MapReduce;user tolerance;big data3|3|1更新时间：2025-07-08
- 摘要：Identifying key classes can help software engineers understand software systems that they previously were not familiar with.Though there are some methods on the identification of key classes,a majority of them use un-weighted dependency graphs,neglecting the coupling types and frequencies.In this paper,we propose a method to identify the key classes based on weighted k-core analysis of software networks.First,it uses a weighted class coupling network to represent classes (interfaces) and their couplings and coupling frequencies.Then,we introduce the weighted k-core decomposition method to compute the weighted coreness for each class (interface).Finally,we use the weighted coreness to quantify the importance of classes (interfaces) and sort them in a descending order with respect to their weighted corenesses.And the top-ranked classes (interfaces) will serve as the key class candidates.Empirical results show the effectiveness of our approach.关键词：key class;weighted k-core decomposition;software network;program comprehension4|4|0更新时间：2025-07-08
- 摘要：One of the main drawbacks in orthogonal frequency division multiplexing (OFDM) systems is high peak to average power ratio (PAPR) which reduces the efficiency of high power amplifier (HPA),and the nonlinear distortion caused by HPA will degrade the bite error rate (BER) of the system.The proposed scheme of this paper considers the nonlinear distortion caused by clipping and HPA as a whole,and models the whole nonlinear process utilizing the sparsity in time domain similar to the clipping noise.The PAPR of OFDM signal is reduced by clipping at the transmitter,and for the receiver,reliable observations contaminated by less channel noise are selected to minimize the influence of channel noise,and compressive sensing (CS) algorithm is applied to effectively recover the total nonlinear distortion signal with the parameters calculated from the nonlinear model,which can improve the BER performance of the system.关键词：orthogonal frequency division multiplexing (OFDM);peak to average power ratio (PAPR);clipping;nonlinear distortion recovery;compressive sensing (CS)2|3|3更新时间：2025-07-08
- 摘要：A topical hierarchy at different levels of granularity from short texts has many valuable applications in the areas of opinion analysis,vision detection,semantics mining and graph construction.Aiming at how to mine the hierarchy of topics from short texts,a topical hierarchy mining framework integrated anchor extraction is proposed based on the modification of the tradition phrase definition.Firstly,the topic inference and the anchor extraction are conducted in the proposed framework.Secondly,frequent anchor phrases are found by applying associate rule mining.Finally,a kind of rank method is used to quantity the criterion of anchor phrases in order to find the most representative topical phrase by ranking.Compared to the topic analysis method of the word co-occurrence graph,the word co-occurrence integrated into anchor is more beneficial to build the higher level of topics.Experiments with datasets from the two Chinese short texts are performed,and the results show that the proposed method can generate interpretably phrases and be used for classification prediction.关键词：short texts;word co-occurrence graph;topical hierarchy;anchor word3|5|2更新时间：2025-07-08
- 摘要：Naming and resolving as the core components of the Internet,the static design and the lack of extensibility is the main cause of the rigid architecture.To tackle the ossification of the core network layer,a dynamic service of naming and resolving is proposed.The service allows to design,build and deploy multiple address strategies on-demand to support the application requirements.Through the elaborate elements,the general address description based on the xml provides a unified expression and resolution of the heterogeneous naming models.Based on pre-configured binding topology,the dynamic resolving service can introduce the new namespaces,entities and resolution mechanisms with transparency.Test results show that the service is provided with good performance and scalability.Compared with the traditional Internet address system,the service can promote the evolution and innovation of the Internet architecture.关键词：naming;resolving;general address description;dynamic resolving;Internet address2|3|1更新时间：2025-07-08
- 摘要：In an underlay cognitive radio network,secondary user (SU) is allowed to access the spectrum when the primary user (PU) is transmitting.At this time,both of SU and eavesdropper will be interfered by PU.Using cooperative jamming technology,the interference produced by PU can be used to improve the physical layer security of SU.Based on this,a novel cooperative physical layer security scheme will be proposed for an underlay cognitive radio network with multiple PUs and SUs.In the proposed scheme,in order to maximize the total security capacity obtained by all SUs under the premise of guarantee of PUs' communication quality,a suitable spectrum access and power control method is designed for SU.Moreover,considering the impact on the access stability of individual rational and selfish,the spectrum access selection problem is formulated as a one-to-one two-side matching.The stability of spectrum access can be guaranteed through building a stable matching between PUs and SUs.The simulation results show that through using the proposed scheme,the communication quality of PU can be guaranteed,and the total secrecy capacity obtained by all SUs can be efficiently improved.关键词：cognitive radio networks;physical layer security;stackelberg game;stable matching179|231|0更新时间：2025-07-08
- 摘要：In view of the problems of the published methods of the ISPFRM functions optimization which couldn't deal with large functions,a novel method for large ISPFRM function optimization was proposed which consists of the representation of product term in integer form,the polarity conversion method using the binary interpolation,and the circuit area optimization of ISFPRM using the bit-wise operation and the genetic algorithm.The proposed algorithm could deal with those functions with large inputs effectively,and has been implemented in C and tested under MCNC benchmarks.The experimental results show that it can deal with the large function with 199 inputs,and the speed of the algorithm is not sensitive to the functions' polarity.After the introduction of DC terms,the circuit area is further optimized.关键词：ISFPRM(Incompletely Specified Fixed Polarity Reed-Muller);binary interpolation;bit operation;genetic algorithm129|142|2更新时间：2025-07-08
- 摘要：Secure multiparty computation has become a focus in the international cryptographic community in recent years.In this paper,we consider how to privately determine whether multiple private data owned by different parties are equal.There is very little literature on this problem at present.To solve this problem,we first propose a new encoding scheme and then use this new encoding scheme together with the threshold ElGamal homomorphic encryption scheme and secret sharing to construct our protocols.We prove that these protocols are private in the semi-honest model by using the well-accepted simulation paradigm.These protocols are also private against collision attack.Efficiency analysis shows that these protocols are efficient.We further construct a protocol that is secure in the malicious model.关键词：secure multiparty computation;multi-data equality test;encoding scheme;simulation paradigm;semi-honest model;malicious model183|317|2更新时间：2025-07-08
- 摘要：The reasonable pricing of big data is one of the most challenging problems in big data transaction,which needs to be solved urgently.This paper,based on Micali-Rabin's secure computing technology,presents a secure delegation auction scheme with the function of big data pricing.First,based on Micali-Rabin's random vector representation methods,we design an auction,as well as a verification algorithm with the property of the sealed bid.Second,the big data's integrity and non-repudiation of the reserve price are realized by Merkle tree and Bit commitment protocol respectively,especially in the pricing stage the use of a special multi-party security computing protocol to hide the reserve price of big data,whereby ensuring the fairness of the big data transaction.Finally,as the scheme's security and performance analysis indicate that it is particularly suitable for delegation auction in the context of the big data transaction.关键词：big data pricing;Micali-Rabin's random vector representation;anonymity;sealed auction105|257|1更新时间：2025-07-08
- 摘要：A novel ‘combiner-equalizer’ structure of blind Spatial Diversity Equalizer (SDE) is proposed for blind reception of multi-antenna system under frequency-selective fading channels.Three key components,i.e.frequency waveform combiner,equalizer and soft information recycler are jointly processed under this new structure.An iterative BLOCK-SUMPLE algorithm is designed first to calculate weight values for multi-antenna signals,with frequency waveform combining implemented afterwards.In order to compensate and optimize the equivalent synthesis channel,soft symbols from the equalizer output are fed back and functioned as a new reference to adjust the weight phases.Compared with traditional blind SDEs,no prior symbol information is required during the implementation.The proposed structure also improves diversity combining performance and reduces the design complexity of equalizer at the same time.Simulation results show that this new structure effectively improves the reception capability under fading channels and it performs closely to the optimal Spatial Diversity Equalizers.关键词：fading channels;spatial diversity equalizer;frequency-domain waveform combining136|189|1更新时间：2025-07-08
- 摘要：As the size of MOS device shrinks,the reliability effect becomes a prominent problem that limits the lifetime of the device.Negative bias temperature instability (NBTI) of PMOSFET is one of the key issues.NBTI degradation is closely related to the device geometry.In this paper,we investigate the NBTI effect of 65nm PMOSFET.By experiment,we obtain the dependency of NBTI degradation on device structure,and find that the NBTI damage of 65nm PMOSFET in this paper increases with the decrease of the channel width.By the method of defect charge analysis and TCAD simulation,we reveal the reason on the experimental result from the point of view of defect generation source and position.It is pointed out that the electric field and the defect charge in the shallow trench isolation (STI) region are the main causes of this phenomenon.The results provide a reference for device reliability design.关键词：65nm;NBTI;channel width166|224|0更新时间：2025-07-08
- 摘要：Double-rotator-structure ternary optical processor (DRSTOP) has two characteristics,namely,giant data-bits parallel computing and reconfigurable processor,which can handle thousands of data bits in parallel,and can run much faster than computers.The super computing power of DRSTOP depends on the corresponding control information.This paper describes the principle and structure of DRSTOP,and presents a new control information generation method based on row operation unit.Based on this method,DRSTOP can deal with user's computing requests automatically,and then it can be used as a powerful computing node and integrated into the parallel platform to solve the problem of large-scale data calculation.Finally,a series of experiments are carried out to verify the proposed control information generation method.The experimental results show that the method is correct,complete and feasible.关键词：double rotator structure;ternary optical processor;control information;reconfiguration command126|147|0更新时间：2025-07-08
- 摘要：In the Remote Field Eddy Current Testing (RFECT) of joint casings,the two penetrations of eddy current will enhance the complicacy of analyzing joint casings.Based on our previous studies,the secondary peaks that caused by transmitter passing defects can be removed by employing two pick-up coils in remote field.However,when transmitter at normal pipe locations,there are not any secondary peaks,and nothing will be removed.The pipe information near transmitter is still contained in testing signals.In order to overcome this shortcoming,based on the pick-up coils,this paper deduced the method for removing Normal Pipe Value (NPV) caused by transmitter from testing signals.Firstly,the Wiener deconvolution filter is adopted to identify the signal that can be used to indicate defects.Secondly,based on the signal obtained by Wiener filter,the self-adapting acquisition of NPV is achieved.The correctness and feasibility of proposed method are validated by testing tool and Kesuo #1 well.关键词：RFEC testing;joint casings;pick-up coils;secondary peaks;Wiener deconvolution filter90|154|0更新时间：2025-07-08
- 摘要：To reduce the on-resistance and enhance the breakdown voltage of silicon on insulator (SOI),a Dual-Trench-Gate silicon on insulator device with a L-shaped gate field plate is proposed by using the field plate (FP) technology.On the basis of the dual-trench structure,a second gate is formed in the oxidation trench,and the L-shaped gate field plate is formed in the extension of the second gate.The drift region length is folded,the breakdown voltage is increased.The dual gates form dual conduction channels,which widen the vertical conduction area and reduced the specific on-resistance.The L-shaped gate field plate modulates the electric field in the drift region,increases the optimized doping concentration of the drift region significantly and further reduces the specific on-resistance.The simulator results show that under the condition of the highest FOM,as compared with a conventional SOI device at the same cell pitch,the breakdown voltage is increased by 123%,and the specific on-resistance is reduced by 32%.The specific on-resistance is reduced by 87.5% at the same breakdown voltage.Compared with a dual-trench SOI device with the same cell pitch,the proposed device not only maintains the high breakdown voltage as the dual-trench SOI device,but also reduces the specific on-resistance by 46%.关键词：field plate;breakdown voltage;specific on-resistance127|148|1更新时间：2025-07-08
- 摘要：In order to improve the heat dissipation capacity of chip with high heat flux density,this paper presents some bionic micro channel topologic structures which are designed based on natureral network topologies with excellent heat and mass transfer characteristic.Then the heat dissipation and pressure drop of different topologies are analyzed by numerical simulation.The calculation results indicate that there exists differences in the heat dissipation capacity of different topologies.With the increasing of heat flux density,the differences become more obvious.The heat dissipation characteristics of the spider web structure with excellent performance are analyzed theoretically.The micro-channel heat sink is fabricated by 3D printing.The testing results indicate that the heat dissipation capacity of the spider web structure has a better performance than current existing flat micro-channel.关键词：chip;bionics;micro-channel;topology;characteristic of heat transfer89|610|6更新时间：2025-07-08
- 摘要：the transfer function of the fractional low-pass filter is approximated as a Butterworth filter.The coefficients of the transfer function are calculated after determining the order and the cutoff frequency.Then,the circuit design,simulation and circuit implementation are based on the transfer function.In this paper,the circuit in any order can be implemented by changing few parts of the circuit which has a strong flexibility.关键词：Butterworth filter;fractional calwlus;fractional filter110|267|6更新时间：2025-07-08
- 摘要：The researches on the efficiency of edge attack strategies for complex networks often ignored the edge's attack cost in the past.Aiming at this problem,we propose a new method to investigate the network robustness based on edge's attack cost in this paper.This method takes the factor of edge's attack cost into account.Edge's weight is used to approximately measure the attack cost of edges.The relative size of giant connected component is used to quantify the network robustness.The robustness of synthetic datasets and real networks is investigated when the attack cost of edges is present.Moreover,the impacts of edge's weight on network robustness are discussed.The experimental results show that when the edge's attack cost is low,the attack effect of low-weight removal strategy (LW) is the best for complex networks.For synthetic datasets,BA(Barabasi-Albert) networks are more robust than WS(Watts-Strogatz) networks under high-weight removal strategy (HW).The robustness of real networks can be optimized by adjusting the edge's weights.Compared with existing methods,our method may be more practical for investigating the network robustness.Simulation results show the validity and feasibility of the method.关键词：complex networks;robustness;edge's weight;attack cost;attack strategies231|216|2更新时间：2025-07-08
- 摘要：A location method based on compressive sensing about multi radiation source is proposed,which can accurately estimate the number of the unknown multiple radiation sources and locate them.In this method,the field strength values are obtained in the partial position of the determined region by mobile monitoring.Due to the spatial sparsity of the target source,the compressive sensing method combined with the propagation model is used for coarse location after the preprocessing of the field strength value.In this way,the number of unknown radiation sources in the region is reconstructed with less field strength values.On this basis,in order to improve the positioning accuracy,genetic algorithm is used to locate the position of the radiation source in second positioning.Through the simulation and experimental verification of the algorithm,it is proved that the method is effective.关键词：location algorithm;mobile monitoring;field strength;compressive sensing;coarse location166|213|1更新时间：2025-07-08
- 摘要：Automatic detection of granary storage quantity is an important technology for national food security.In this paper,according to the characteristics of grain peaks,the mathematical relationship between granary storage weight and the bottom/side pressure of granaries is established;the feasibility of the online granary storage quantity detection based on pressure sensors is also demonstrated.Furthermore,a new granary storage weight detection model based on polynomial expansion is proposed by using pressure sensors arranged along the inner and outer rings.The polynomial expansion of the average value of the pressure sensors is used to evaluate the granary storage weight.As the average value fluctuates inpractical warehouse detection,a granary storage weight detection model based on SVR is proposed.The detailed extraction method for SVR input sequences is described,and specific modeling algorithm is designed.Practical storage weight detection results show that the detection accuracy of the proposed model is better than 97%,which demonstrates that the proposed granary storage weight detection model is effective and well meet the demand of national granary storage quantity detection.关键词：grain storage weight monitoring;pressure sensor;detection model;support vector regression(SVR);detection accuracy130|200|2更新时间：2025-07-08
- 摘要：In order to improve the localization accuracy of TOA (Time of Arrival) in distributed acoustic source localization system,the CRLB (Cramer Rao Lower Bound) of localization error is deduced by taking the node performance difference into account.The adaptive genetic algorithm is used to study the optimal sensor placement by minimizing the average CRLB when the target is uniform probability distribution and Gauss distribution probability scenario in the field interested.The simulation results show that the optimal sensor placement based on the sensor observation performance is directly related to the probability distribution of sound source in the detection area.关键词：TOA(Time of Arrival);optimal placement;sensor performance;adaptive genetic algorithm103|290|4更新时间：2025-07-08
- 摘要：Based on the features of the output one-pulse-per-second (1PPS) signal of the Global Positioning System (GPS) receiver,and the characteristics of the output frequency signal of the Coherent Population Trapping (CPT) atomic clock,we design and realize a GPS-disciplined CPT atomic clock device.For depressing jitter noise of the 1 PPS signal,we have established the corresponding Kalman filter mathematics model,obtained the noise parameters through theoretical calculation.We have experimentally filter processed the frequency signal of CPT atomic clock with a combination of the Averaging filter and Kalman filter,and calibrated the output frequency of CPT atomic clock with the 1PPS signal,and achieved that reducing the medium and short term frequency error by half magnitude and improving day frequency stability by one order of magnitude.关键词：atomic clock;frequency measurement;kalman filter;global positioning system229|288|6更新时间：2025-07-08
- 摘要：Focusing on the problem of multi slots and large amount of data traffic in RFID tree anti-collision algorithm,an improved anti-collision algorithm based on multi-tree is proposed.The reader can detect the collision accurately and send feedback to the tags regarding the collision bits information.The tag shields the known ID bits of the reader and converts the ID number into the serial number of consecutive collisions.The reader makes use of shield bits information and the collision bits coding information returned by the tags in order to search the tags in a hierarchical classified manner.By shielding the tag ID,the reader and the tag only sends the collision bits information which the other party unknown.The algorithm reduces the collision time slots and the recognition time slots,avoids the idle time slots,and reduces the communication data between the reader and the tags.Theoretical analysis and simulation results show that the algorithm reduces the total slots and data traffic,and improves the recognition efficiency of reader.关键词：bit-shield;RFID;anti-collision;multi-tree;pre query130|143|2更新时间：2025-07-08
- 摘要：Magnetic resonance elastography (MRE) is a new solution to detect and visualize the biomechanical properties of soft tissues.Brain lesions often lead to the changes of biomechanical properties.Therefore,the study of brain soft tissues by using MRE has great significance.However,the study confronts of the complicated brain structure,as well as the costs of MRE scanning.It is thus attractive to develop an effective numerical MRE platform which can depict the propagation of various elastic wave probes through brain tissues.On one hand,the results lead to the quantitative evaluation of the efficiency of various elastic wave probes.On the other hand,they can support the study of new MRE algorithms for elasticity reconstruction.A series of quantitative experiments have been carried out,and the results validate the effectiveness of this numerical MRE platform.关键词：brain tissue;elastic wave;magnetic resonance elastography;numerical simulation221|254|1更新时间：2025-07-08
- 摘要：Recently,there has been an upsurge of interest in full-duplex(FD) system with simultaneous wireless information and power transfer(SWIPT).Differing from the existing work,this paper optimizes the sum rates(SR) of multi-antenna FD-SWIPT system and considers its robustness and energy efficiency,also,this paper proposes robust precoding design and energy-efficient timeslot allocation scheme for FD-SWIPT system.On account of numerous variables,this optimization problem is of non-convex and hence difficult to solve.Firstly,in order to reduce the influence of self-interference,the self-interference is cancelled based on singular value decomposition(SVD) and mean-square-error(MSE) algorithm.Then,with the fixed timeslot allocation factor,on condition that there is evaluated error for self-interference channel,we propose the robust precoding design for the original problem based on first-order Taylor's series approximation,and the corresponding iterative algorithm is given.Furthermore,the timeslot allocation schemes under different constraints are proposed,and the optimal solution of timeslot allocation Factors is deduced.Finally,the performance advantages of the proposed scheme are verified by comparing the simulation experiment with the existing results.关键词：full-duplex;simultaneous wireless information and power transfer;robust precoding;timeslot allocation;self-interference cancellation;energy efficiency149|200|1更新时间：2025-07-08
- 摘要：Directional coupler is commonly used in the microwave system to measure the forward and backward power.Due to the limited directional isolation of the coupler,the crosstalk existing between the bi-directional coupling output signals will influence the accuracy of power measurement.The quadrature directional coupling method is developed to solve this problem.A pair of directional couplers with a phase difference of 90° are used to measure the coupling output power simultaneously,and the influence of crosstalk can be eliminated effectively by processing the measurement data.The relationship between forward and backward power and the outputs of quadrature couplers is derived,and the error due to the quadrature deviation is analyzed.In order to determine the quadrature situation,the method to measure the phase difference between two couplers is proposed.The experiment shows that the quadrature directional method can improve the accuracy of power and VSWR measurement effectively.关键词：microwave system;microwave power measurement;directional coupler;isolation;quadrature99|207|0更新时间：2025-07-08
- 摘要：In heterogeneous wireless network,most users hope to obtain the most satisfactory network services at a lower cost.This paper proposes a user-centered cost-aware network handoff scheme.Firstly,the model of user's service saturation is established according to the network transmission rate that can be obtained by the user.Secondly,combined with the normalized network cost,network handoff problem can be converted to a multi-objective optimization problem.Considering the network congestion is caused by a large number of users choose the same network at the same time,the user decision behavior in this context is transformed into EI Farol bar problem,and then we get the service saturation expectations of users from the network service probability by searching Nash equilibrium of the problem.Finally,the multi-objective optimization problem is transformed into a maximization problem by considering the reward rate of user's service saturation.Simulation results show that the proposed algorithm can improve the total throughput of the network,reduce the blocking rate of the user's handoff and make the network load more balanced.关键词：heterogeneous wireless network;vertical handoff;EI farol;cost-aware249|191|3更新时间：2025-07-08
- 摘要：Rough set theory is one of important methods of granular computing,and data heterogeneities are one of remarkable characteristics in big data.For data heterogeneities,we define attribute reduction for concepts after investigating intrinsic quality of attribute reducts,which can contain value reducts,Pawlak attribute reducts and parallel reducts.After investigating properties of concept-attribute-reduction,we present a new method to reduce redundant attributes and a new method to detect concept drift for heterogeneous concepts.Theoretical analysis and examples show that these methods are valid.This work provides a new type way for rough set theory and granular computing to integrate into big data.关键词：granular computing;F-rough sets;attribute reduction;heterogeneous data;concept drifting210|155|2更新时间：2025-07-08
- 摘要：To solve the problem that the traditional Mash structure has low signal-to-noise ratio because of mismatch at each levels,in this paper,the traditional sigma-delta (Σ-Δ) structure is realized by using the phase accumulator,which is easy to realize the hardware description language of the whole system,thus fundamentally solving the mismatch between the different stages.In the design of the interpolation filter,the use of optimized half-band filter structure and cascaded integral comb filter,saving hardware resources.The circuit uses the Magnachip 180nm 1P4M standard CMOS process,the chip area is only 0.2025mm2 (0.45×0.45),the measured chip signal to Noise and Distortion Ratio(SNDR) to 90dB.109|248|2更新时间：2025-07-08
- 摘要：Based on the analysis of the existing fuzzy density calculation methods,this paper explores a new method of calculating fuzzy density from the membership degree distribution and output consistency of the classifiers,and proposes a dynamic fuzzy density assignment method based on decision trust and support degree,which aims to describe the reliability of the classifier in the fusion system in real time according to the objective information output when each classifier identifies the specific target.The experimental results on facial expression recognition show that the proposed method can effectively improve the decision performance of fuzzy integral fusion and reduce the interference of unreliable decision information output by single classifier,which is an effective multi-classifier fusion method.关键词：multi-classifier fusion;fuzzy integral;fuzzy density;facial expression recognition197|140|1更新时间：2025-07-08
- 摘要：In order to make up the drawbacks that convolutional neural networks lack the ability of spatial structured learning in RGB-D scene parsing,we propose spatial structured inference deep fusion networks (SSIDFNs) on the basis of deep learning,the embedded structural inference layer organically combines conditional random fields (CRFs) and spatial structured inference model,which is able to learn the three-dimensional spatial distributions of objects and three-dimensional spatial relationships among objects in a more comprehensive and accurate way.Furthermore,the feature fusion layer takes both advantages of deep belief networks and improved CRFs,which is able to achieve deep structured learning according to the comprehensive semantic information of objects and semantic correlation in formation among objects.The experimental results demonstrate that the proposed SSIDFNs achieve the best mean accuracy 53.8% and 54.6% on the standard RGB-D datasets NYUDv2 and SUNRGBD respectively,which will be helpful to implement intelligent computer vision tasks,such as robot task planning and self-driving cars.关键词：RGB-D scene parsing;deep learning;convolutional neural networks;conditional random fields;spatial structured inference model;deep belief networks;computer vision;robot task planning;self-driving cars373|315|3更新时间：2025-07-08
- 摘要：In the future networks,there will be a large number of machine-to-machine (M2M) communication terminals,which are at least two orders of magnitude higher than the user equipments (UEs).The traditional resource allocation algorithm cannot meet the requirements of the new service.Under the scenario of coexistence of H2H and M2M,this paper presents a resource allocation algorithm based on knapsack model by analyzing the characteristics of M2M terminals.This new algorithm can guarantee the QoS of H2H and delay sensitive M2M communication service,while taking full account of the characteristics of non-sensitive M2M communication service to save energy consumption.Simulation results show that the algorithm can improve the resource utilization rate and simultaneously satisfy the QoS of H2H and M2M services.关键词：machine-to-machine communication;resource allocation;knapsack problem102|163|4更新时间：2025-07-08
- 摘要：This paper presents a novel three-dimension (3D) non-wide-sense stationary (non-WSS) geometry-based channel model for vehicle-to-vehicle (V2V) communication environments.We introduce the two-cylinder model to describe the moving vehicles and elliptic-cylinder models to depict the stationary roadside scenarios.The relative movement between the mobile transmitter (MT) and mobile receiver (MR) results in the time-varying geometric statistics that make our channel model non-stationary.Furthermore,the proposed channel statistics,i.e.,the time-varying space correlation functions (CFs) and Doppler power spectral density (PSD) are studied for different relative moving time instants.The results show that the proposed 3D non-WSS channel model is practical for characterizing real V2V channels.关键词：3D channel model;vehicle-to-vehicle;space correlation functions;Doppler power spectral density82|187|4更新时间：2025-07-08
- 摘要：This paper analyzes the characteristics and problems of the emergency response plan clusters in China,and establishes a Hypernetwork based model for emergency response plan clusters consisting of meta factors as area,subject and resource.Taking Wenchuan earthquake as a research case,the corresponding hyper-network model was constructed and some feature indexes of the hyper-network were analyzed.The results indicate that the model constructed in this paper has the high clustering property and a smaller average path length with small-world effects,revealing the synergetic trends among heterogeneous levels,homogeneous levels respectively,of the plan clusters,and providing a generic example for the similar research.102|176|1更新时间：2025-07-08
- 摘要：Spatio-temporal Top-k query results in TMWSNs (Two-tiered Mobile Wireless Sensor Networks) are facing threats.To preserve the integrity of the Top-k query results in TMWSNs,a novel integrity-ensured protocol named VIP-TQ is proposed for spatio-temporal Top-k queries in TMWSNs in this paper.VIP-TQ achieves integrity preserving for spatio-temporal Top-k queries by using several novel techniques such as node virtualization and binding encryption,and some novel methods such as the method of data pre-processing on the sensor nodes,the method of spatio-temporal Top-k query processing on the data storage node and the method of completeness verification on the Sink node.Theoretical analysis and simulation results show that VIP-TQ can detect the incomplete Top-k query results with probability 100% with high energy efficiency.关键词：two-tiered mobile wireless sensor networks;spatio-temporal Top-k queries;integrity preservation;location correlation;multilayer cooperation150|192|1更新时间：2025-07-08
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