最新刊期
卷 47 ， 期 11 ， 2019
- 摘要：The RF connectors and micro strip lines are commonly used in communication system circuits, and the characteristic impedance discontinuity caused by the welding transition section increases the signal loss in the circuit. In this paper,the welding transition section of the RF connector and micro strip line is studied. Based on the transmission line theory, the equivalent circuit model of the welding transition section is established. The reasons for the characteristic impedance discontinuity of the welding transition section are discussed, and the compensation schemes are proposed.In addition, the electrical parameters of the equivalent circuit model are extracted by the joint simulation of electromagnetic field and circuit. From the perspective of the equivalent circuit model, the influence of the compensation scheme on the complex electromagnetic characteristics of the solder transition section is analyzed. The finite element analysis and experimental results show that the matching and transmission performance of the compensated components is significantly improved, which proves that the compensation scheme is effective.关键词：equivalent circuit model;welding transition section;impedance discontinuitiy;compensation122|478|0更新时间：2025-07-16
- 摘要：The demand for in-vehicle communication services has increased the power consumption of base stations (BSs) and reduced the reliability of their data transmission. This paper presents a relay selection strategy for two-stage multicast transmission of vehicle security data (TSMT-VSD) under cellular networks. In this strategy,the selected relay range is first determined on the premise of saving total power consumption, and then the optimal multicast radius x0 with the lowest BS power consumption is calculated, followed by choosing the vehicle closest to the optimal multicast radius x0 as the relay. Furthermore, based on the social attributes of relays, an asymmetric evolutionary game model between BS groups and relay groups is established,and a reward and punishment mechanism for dynamic redistribution of relay entertainment data transmission power without affecting secure data transmission is designed. The simulation results show that the proposed relay selection strategy and the designed reward and punishment mechanism can not only ensure the reliability of TSMT-VSD, but also save at least 25% power consumption of BS compared with the conventional one-stage multicast transmission, provided that the number of vehicles is beyond the bound Kmin.关键词：relay selection;vehicular communication;security data;evolutionary game101|123|1更新时间：2025-07-16
- 摘要：The length of the cantilever beam electrode is one of the important factors affecting the characteristics of piezoelectric vibration energy harvesting. The energy distribution function was proposed to describe the relationship between electric field energy and electrode ratio during the vibration energy harvesting, and the nature of the effect of electrode ratio on electrical characteristics was also explored. It is pointed out that the optimal electrode ratio of the rectangular and triangular cantilever beams to obtain the maximum power is between 50%~60%. In addition, the charge is redistributed with energy loss during vibration energy harvesting, and the energy loss is lowest at the optimal electrode and greater when the electrode ratio reaches 100%. Both the simulation and experiment results show that the optimal electrode ratio of the rectangular and triangular cantilever beams is in accordance with the optimal value obtained by the energy distribution function, and it is feasible to increase the output power by optimizing the electrode-length.关键词：piezoelectric cantilever beam;energy harvesting;electrode length;electrical characteristics58|112|1更新时间：2025-07-16
- 摘要：A dual memristive shinriki oscillator is proposed through expanding Shinriki oscillator with an active charge-controlled memristor and substituting the series-parallel diode loop in the original circuit with a flux-controlled memristor with an absolute value term. Firstly, the mathematical model of the memristive oscillator is established according to the circuit topology diagram. Secondly, the coexisting bifurcations and routes to period-chaos transitions are analyzed when the circuit parameters are changed. Results show that Shinriki oscillator with double memristors exhibits a great dependence on parameter values and initial conditions of memristors. When the parameter values and initial conditions vary in a particular domain, the oscillator will exhibit nonlinear dynamical behaviors such as the phenomenon of coexisting antimonotonicity,incomplete symmetric behaviors, extreme multistability, etc. Moreover, the digital module circuit of the oscillator is constructed by the FPGA development board. The experimental waveform is captured on the oscilloscope, which verifies the accuracy of numerical simulation.关键词：memristive Shinriki oscillator;antimonotonicity;extreme multistability;FPGA(field-programmable gate array)65|258|2更新时间：2025-07-16
- 摘要：Conical spiral inductor is a new type of inductor with good consistency over a wide frequency band. It is widely used in bias junction circuits, amplifier circuits, and RoF (Radio-over-Fiber) systems. In this paper, the calculation method of the inductance value of spiral conical inductor, the length of spiral inductor and the DC resistance are studied, and the exact calculation formula is given. The sensitivity error is less than 10.2%, and the DC resistance error is less than 6.5%. At the same time, the microwave characteristic of the conical hollow spiral inductor is studied, and an equivalent model is put forward. The model is in good agreement with the measured curve. The influence of the winding parameters on the inductance is analyzed, and the parameter α of the length-inductance and the inductance-frequency parameter β are introduced to optimize the characteristics of the ultra-wideband conical inductor.关键词：conical shape inductor;inductance;equivalent model;ultra-wideband;DC resistance60|176|0更新时间：2025-07-16
- 摘要：Through-Silicon Via (TSV) is prone to introduce resistive open and leakage faults during the manufacturing process, which will seriously affect the reliability and yield of 3D chips, so the pre-bond TSV testing seems necessary. Existing pre-bond TSV testing methods still have some problems, such as incomplete fault coverage,large area overhead and large testing time. To tackle these problems, an edge transition delay based pre-bond TSV testing method is proposed in this paper. This method mainly measures the variation of TSV delay caused by physical defects, and separates the rising and falling edges to eliminate the interaction between them. Firstly, the variation of rise-time delay is transformed into a pulse signal with corresponding width; then, the pulse width is measured by pulse width reduction technology; finally, the measurement results are extracted by the state of trigger and compared with the reference value of fault-free TSV. The experimental results show that the proposed method performs better than the existing methods in terms of fault coverage,and area overhead.关键词：3D Chip;TSV(Through-Silicon Via)testing;open fault;leakage fault129|130|2更新时间：2025-07-16
- 摘要：How to migrate a source domain knowledge model with a large amount of tagged data to a target domain with a small amount of tagged data is a hot issue in few-shot learning. For the problems that the existing few-shot learning algorithm have weak generalization ability when the difference between the feature distribution of the source domain data and the target domain data is large, a few-shot learning model based on semi-supervised FSLSS (Few-Shot Learning based on Semi-Supervised) is proposed. Firstly, a relational deep learning network is established by using the pytorch framework,and the network is pre-trained by the source domain data. Then, the network is used to predict the target domain data, and the label with the highest classification probability is used as the data's pseudo label. Finally, the network is hybrid trained using the pseudo label data of the target domain and the real label data of the source domain, then repeating the pseudo-labeled and hybrid trained process. The experimental results show that the FSLSS model has better generalization ability and knowledge transfer effect than the existing few-shot learning algorithms.关键词：few-shot learning;semi-supervised learning;pseudo label;transfer learning104|237|9更新时间：2025-07-16
- 摘要：During the pilot's departure from the ship, the information of the ascending and descending of the pilot's departure from the ship could not fully rely on the single acceleration threshold judgement method, resulting in a erroneous judgement of the information. For this reason, a dual signal filtering algorithm based on human posture had been proposed to monitor the departure ship. The attitude sensor equipments had been collected for the attitude data, and the Kalman filter has been used to filter out the noise, estimating the posture state of the human body. A software digital low pass filter had been constructed to filter the influence of gravity acceleration. Then the FIR filter had been constructed to filter the noise in the linear acceleration, and had detected the attitude information during the pilot's departure, and Realization of Linkage with Safety Climbing Protective Device. The experimental results show the detection method realizes the attitude judgment of pilot boarding ship and reduces the incorrect operation rate, being better divided into other incorrect behavior.关键词：posture judgment;pilot;boarding;filtering43|215|1更新时间：2025-07-16
- 摘要：DKCHER is a knowledge compilation algorithm of computing difference based on hyper extension rule, which is the best EPCCL compiler so far. We research the executing process of DKCHER algorithm in this paper, and design MOVR (maximum occurrence number of variables in middle result) heuristics, which is used to dynamically select the clause with maximum occurrence number of variables in middle result. By combining MOVR heuristics with DKCHER, MOVR_DKCHER algorithm is designed. Experimentally, MOVR heuristics can significantly improve the compilation efficiency and compilation quality of DKCHER, in which the compilation efficiency of DKCHER can be averagely improved about 70 times, and the improvement can be up to 237 times at most.关键词：knowledge compilation;extension rule;hyper extension rule;EPCCL theory;heuristic strategy100|175|0更新时间：2025-07-16
- 摘要：According to the segmented current steering digital-to-analog converter (DAC), the influence of current mismatch and parasitics in the current array on the nonlinearity of DAC is discussed by theoretical analysis and derivation. A layout plan for the current array, QN rotary walk scheme is utilized for optimizing the nonlinearity of DAC. The metal connection in this layout scheme is relatively simple and the current mismatch caused by parasitic effect is small. With the segmented structure of 6 bit thermometer code and 4 bit binary code, a 10 bit DAC is realized in a 0.18μm CMOS by using the above layout plan. The measurement results show that the differential non-linearity (DNL) and the integral non-linearity (INL) of the DAC with QN rotary layout scheme are 0.77 LSB and 1.12 LSB. With 500MS/s sampling rate and 1.465MHz input frequency, the spurious free dynamic range (SFDR) and the effective number of bits (ENOB) are 64.9dB and 8.8bit, respectively.97|161|1更新时间：2025-07-16
- 摘要：Asymmetric quantum codes are an efficient coding scheme against different kinds of quantum errors in quantum communication, which occurs with different probability. The good quantum codes play a decisive role in ensuring the authenticity and reliability of quantum communication.In this paper, we first present Hermitian dual-containing conditions of the imprimitive narrow-sense BCH codes by a detailed analysis of cyclotomic cosets. Secondly, a series of asymmetric quantum BCH codes with special code length are constructed via the generalized CSS construction. Finally, dimensions of two types of asymmetric quantum BCH codes are determined for m as 3 and 5 respectively, whose z distances are much greater than the results in the literature. Hence, the error-correcting ability to the phase errors can be further improved.关键词：asymmetric quantum code;imprimitive BCH code;Hermitian dual containing condition;CSS construction59|104|0更新时间：2025-07-16
- 摘要：Improving the ruggedness of radio frequency power device is beneficial to enhance the ability of withstanding electro-static discharge (ESD) and output mis-match. To understand the electrical process happened in device intuitively, the electrical mechanism of state-of-art high-ruggedness N-channel RF-LDMOS (Radio Frequency Lateral Diffusion MOS), under TLP (Transmission Line Pulse) stress,has been studied. RF-LDMOS FETs with different gate widths had been manufactured using advanced 0.18μm BCD (Bipolar/CMOS/DMOS) process. It is found that the different failure points of simulation and measurement are coming from the random failure of ESD stress and thermal problems. The simulation results of different nodes under TLP stress proved that the P buried layer under source area plays an important role in holes flowing, and improves the ruggedness of RF-LDMOS.关键词：RF power device;LDMOS;chip design;BCD process;TLP;impact ionization;P buried layer186|143|0更新时间：2025-07-16
- 摘要：The selection of the parameters of the stochastic resonance system plays a decisive role in the effect of the output signal. In this paper, aiming at the problem that the stochastic resonance cannot process many kinds of weak communication signals in general, an enhancement method based on adaptive parameter-tuning stochastic resonance is proposed. Firstly, the energy transfer nature of the stochastic resonance is explained from the characteristic subspace of the signal, and a measuring function based on singular value decomposition is presented as the evaluation function. Secondly, after analyzing the effects of two different system parameters, the amplitude normalization is utilized to optimize one single parameter, which reduces the complexity. And the sliding average filter is added to the module to prevent the phenomenon of the amplitude drift. Finally, based on the artificial fish swarm algorithm, the overall framework and specific steps of the method are modularly designed. The simulation result demonstrates that the proposed method can match the noisy signal and the nonlinear system with an average of 4 to 5 iteration convergence speeds for four kinds of signals.关键词：communication signal processing;signal denoising;stochastic resonance;bistable system;low Signal-Noise Ratio (SNR)51|123|2更新时间：2025-07-16
- 摘要：In order to research the effect of propeller rotating speed and flowing velocity on the corrosion static electric field under sea water, a method for the corrosion static electric field under laminar medium is proposed. Combining the theory of hydrodynamics and electrochemistry, the rotational model of curved propeller in laminar flow is established, the momentum integral method and electrochemical method are used to calculate boundary layer thickness and ultimate corrosion current density of curved blade surface in laminar medium respectively. An electric dipole model is established to solve the corrosion static electric field based on the current density, and the correctness of the conclusion is verified by experiments. The results show that the amplitude of electrostatic field increases with the increase of propeller speed and medium velocity. The theoretical data are in good agreement with the experimental data when the velocity and rotational speed are small.关键词：corrosion static electric field;static electric dipole;laminar medium;momentum integral method;curved propeller;current density29|78|1更新时间：2025-07-16
- 摘要：Privacy leakage and utility measurement are widely concerned issues in multi-attribute datasets by non-interactive differential privacy publishing. In this paper, we have proposed several quantification methods by using information entropy and hamming distortion to quantify the privacy of published dataset, utility of dataset and risk of privacy leakage. First, we have tailored the existing mutual information concept to analyze the relationship among associated attributes and constructed an associated dependency graph model to analyze their correlations among multi-attribute. After that, we have developed a privacy quantification method based on information entropy and privacy leakage Markov chain, which is generated based on the graph of privacy leakage path that has a valid efficiency measurement of the privacy leakage leading by associated attributes. Finally, to justify the efficiency of the proposed model, we have included an illustrative example and demonstrated the advantage of our method by comparing with other methods.关键词：differential privacy;information entropy;privacy metric;association attributes41|144|0更新时间：2025-07-16
- 摘要：As a complex high-composite software concept, the trustworthiness research has failed to make substantial progress and breakthroughs during these decades. After analyzing the authority definitions of trustworthiness, this paper demonstrates that the scope of them is contradictory and incompatible. It further illustrates that the research of software trustworthiness conceptual model from its essence is very important and necessary. The term "trustworthiness" originates from sociology; so we should discuss the essence of software trustworthiness based on trust-theory of sociology. This paper constructs a trust system model STM based on hundreds of classical sociological literature on trust-theory. After comparing and mapping with software trust system, the paper proposes a software trustworthiness conceptual model STCM based on trust theory of sociology. Based on STM and STCM, a complete concept definition system of software trustworthiness is presented. Finally, STCM is proved to be feasible and effective by the measurement and evaluation experiment, which provides a new research direction for the advancement of software trustworthiness.关键词：software trustworthiness;trust-theory;STM;STCM;reliability;security38|120|1更新时间：2025-07-16
- 摘要：The network asset vulnerability assessment technology plays an important role in sorting out Internet assets and realizing the security management of network asset vulnerabilities. The existing methods have the issues such as low accuracy of evaluation results and single function due to the inability to effectively obtain the fingerprinting information of the device. Therefore, this paper proposes a construction method of device fingerprinting search engine for network asset vulnerability assessment, which has the advantages of multiple interfaces, strong interactivity, and reduced network redundancy detection. This paper verifies the efficiency of the method by counting and evaluating server types and HTTPS protocol vulnerabilities in real networks.关键词：network assets;vulnerability assessment;device fingerprinting search51|137|0更新时间：2025-07-16
- 摘要：More and more complex multi-objective optimization problems have emerged in the real world, and the novel heuristic algorithms need to be developed to meet the challenge. A multi-objective firefly algorithm based on multiply cooperative strategies (MOFA-MCS) is proposed in the paper. MOFA-MCS uses the method of homogenization and randomization to generate the initial population, adopts the elite solutions in the external archive to lead the firefly to move, exerts Lévy flights to add random disturbance in the moving process, and finally, the ε-three-point shortest path strategy is also applied to maintain the diversity of the archive solutions. MOFA-MCS is compared with other six representative multi-objective evolutionary algorithms on 12 benchmark multi-objective test problems, and the experimental results show that MOFA-MCS has significant performance advantages in terms of convergence and diversity.关键词：multi-objective optimization problem;firefly algorithm;multi-objective firefly algorithm;multiply cooperative strategies185|242|7更新时间：2025-07-16
- 摘要：Direct Position Determination (DPD) algorithms usually focus on line-of-sight target. Aiming at the problems that traditional radio positioning technology is suboptimal, especially in the over-the-horizon target localization, this paper proposes an Over-the-horizon Direct Positioning Determination (ODPD) method with known radiation source waveforms. Based on the ionospheric electron density parameter, the cost function just about the target position is directly derived from the signal data domain through the Maximum Likelihood (ML) criterion. Furthermore, this paper deduces the positioning error covariance matrix considering the measurement error of the ionospheric virtual height. Experiments show that compared with the existing algorithms, the ODPD method can significantly improve the positioning accuracy of the over-the-horizon target at low SNR. The ODPD positioning performance is closer to the Cramér-Rao low bound (CRLB). When the standard deviation of the ionospheric virtual high error is 20km, the positioning error caused can be controlled within the range of 10km.44|126|4更新时间：2025-07-16
- 摘要：Saliency detection is a fundamental issue in computer vision. It is widely applied in fixation prediction, object detection, scene classification, and other visual tasks. In order to improve the precision of visual saliency detection with multi-features, a multi-feature integration algorithm is proposed based on the joint probability distribution of saliency map and combined with priori knowledge. Firstly, the potential defects of single feature saliency detection are analyzed, and the joint probability distribution of saliency maps with multiple features is deduced. Secondly, the priori distribution of the saliency map is deduced based on the rarity,sparsity,compactness and center priori of the saliency map,and the condition distribution of the saliency map is simplified based on the assumption of normal distribution. Then the maximum a posteriori estimation is obtained from the joint probability distribution of the saliency map, and a supervised learning model of the distribution parameters is constructed based on the multi-threshold hypothesis. Experiments show that compared to the highest-precision saliency detection method on single feature, the mean average error of the multi-feature algorithm under the supervised and heuristic method is decreased by 6.98% and 6.81%, and the average F-measure is improved by 1.19% and 1.16%. And the multi-feature integration of single image takes only 11.8ms. The algorithm has high accuracy and real-time performance, and can be combined with the required features and different prior information according to the task. It meets the requirements of saliency detection with multi-features.关键词：saliency detection;joint distribution;multi-feature integration;prior information;exponential distribution family;maximum a posteriori estimation120|207|1更新时间：2025-07-16
- 摘要：The minimum cut problem (MCP) is an NP (Non-deterministic Polynomial)-hard problem,warning propagation (WP) is a kind of message passing algorithm based on factor graph,it solve the combinatorial optimization problem.First,HMM (Hidden Markov Model) converted undirected graph to factor graph.Then,we designed a kind of warning propagation algorithm to solving the minimum cut.Finally,we selected skit randomly undirected graphs numerical experiments.The experimental show that the algorithm precedes similar algorithms in speed.关键词：combinatorial optimization;minimum cut;warning propagation(WP);hidden Markov model(HMM);probability algorithm;Markov off80|183|4更新时间：2025-07-16
- 摘要：Classical nonparametric spectral analysis uses sliding windows to capture the dynamic nature of most real-world time series,however,this universally accepted approach fails to exploit the temporal continuity in the data.For some non-stationary signals that are smooth in time and sparse in frequency,a method of computing the spectrum pursuit estimate by using partly parallel alternating direction method of multipliers (ADMM) was used to obtain time-frequency analysis of this signal.A time-frequency analysis was performed on simulated and real human EEG data using the proposed method.The simulation results show that the proposed method not only effectively improves time and frequency resolution of the spectrum,but also effectively suppresses the noise than short-time Fourier transform.Finally,the convergence of the algorithm was illustrated from the perspective of stopping criterion of ADMM algorithm.关键词：nonparametric spectral analysis;sliding windows;partly parallel Alternating Direction Method of Multipliers (ADMM);spectrum pursuit;time-frequency analysis;frequency resolution;time resolution189|195|1更新时间：2025-07-16
- 摘要：For the technical challenges brought by time/frequency-domain selective fading (double-selective fading) and non-stationary characteristics in channel estimation for orthogonal frequency division multiplexing (OFDM) system,an iterative extend-Kalman filter (iEKF) channel estimation method based on basis expansion model (BEM) with the frame structure of superimposed pilot is proposed.Based on the BEM and the EKF channel estimation method,the channel impulse response (CIR) and the time-varying time-domain autocorrelation coefficient can be jointly estimated to effectively eliminate inter carrier interference (ICI).At the same time,it's need to eliminate the interference of data symbols at the superimposed position.So for the superimposed position,the channel estimation is proposed in which decoupling data and pilot firstly,reconstructing subsequently,and performing the iEKF algorithm finally.The simulation analysis shows that compared with the traditional superimposed pilot channel estimation method and the pilot symbol assisted modulation (PSAM) estimation method,the proposed channel estimation method has higher estimation accuracy,stronger robustness and greaterer throughput in high-speed railway scenario especially under low signal-to-noise ratio (SNR) conditions.关键词：superimposed pilot;double-selective channel;basis extension model;extended-Kalman filter;OFDM;channel estimation178|191|3更新时间：2025-07-16
- 摘要：Impulsive noise can greatly degrade the performance of long wave communications.This paper proposes the optimal design of the Gaussian-tailed zero memory nonlinearity (GZMNL) function to suppress impulsive noise.The GZMNL function which was proposed for the symmetric α-stable (SαS) noise is not robust in applications,because of the lack of adaptive parameters.This paper proposes to design the GZMNL parameters adaptively to control the linear range and the tails,so that the GZMNL can be effective for various noise distributions.In the GZMNL design,the efficiency is employed as the objective function which is maximized over the GZMNL parameters.To solve this optimization problem,we develop a derivative-free optimization algorithm which searches the maximum efficacy adaptively.Considering practical applications,we propose two fast algorithms for the GZMNL design in the SαS noise,as well as a robust method for the GZMNL design in unknown noise distributions.Simulation results based on the SαS noise and real atmospheric noise show that the GZMNL design achieves almost the best nonlinearity in known noise distributions.The GZMNL design is effective and robust for unknown noise distributions.关键词：impulsive noise;nonlinear transformation;GZMNL;efficiency function;nonlinear optimization114|131|2更新时间：2025-07-16
- 摘要：Web applications are constantly exposed to security threats from code injection attacks such as SQL injection in cyberspace.At present,most detection methods against SQL injection attacks have low execution efficiency and low detection accuracy,and are not easy to be reused.According to the characteristics of injection vulnerability,a SQL injection behavior detection method based on aspect-oriented programming and dynamic taint analysis is proposed,the taint analysis process is encapsulated by the aspect unit,so that the typical program crosscutting-concerns are separated from the base system,which improves the reusability of detection code.The Advice mechanism is used to dynamically load the various detection component implementations to execute the detection code at runtime to counter typical code injection attacks such as SQL injection against Web applications.Experiments show that this method can realize the self-protection process without modifying the application execution engine and source code,so as to effectively defend against seven typical types of SQL injection attacks such as tautologies,logically incorrect queries,union query,piggy-backed queries,stored procedures,inference query,alternate encodings,and so on.关键词：Web security;SQL injection;taint analysis;aspect-oriented programming;vulnerability detection141|149|2更新时间：2025-07-16
- 摘要：With the development of digital economy industry driven by IT technologies such as cloud computing, internet of things and artificial intelligence, modern enterprise information demands put forward higher requirements and challenges for data center storage capacity. Due to data storage reliability and redundant arrays of independent disks scalability, RAID system is widely used. In order to fulfill the requirements of massive data for the increasing storage capacity, the industry generally adopts a method of scaling RAID system to solve the problem of storing massive data. E-commerce,web service and finance access data on real-time, which make the data center must provide high-quality service response for users with 7*24,but the factors of data migration,load balane and scaling cost will affect the efficiency of RAID scaling. Therefore, how to design a fast and efficient scaling scheme is getting more and more attention from researchers. According to the different investigative object, this paper classifies RAID scaling approaches into basing on block, object and file system. Meanwhile, according to the investigative developing process and different optimization strategies of RAID scaling, the approaches also can divide into optimizing data migration process and reducing the number of data to be moved. From the perspective of evaluating the performance of the scaling schemes, this article introduces the typical and common scaling schemes by different application scenarios that points out the shortcomings of various scaling schemes and possible improvements. How to balance the factors that affect the performance of the scaling schemes and design a high-performance scaling scheme with less data migration, good load balance,and low scaling cost, which will be a hot issue for massive data storage research for a long time in the future.关键词：massive data storage;RAID scaling;scaling schemes;index of scaling performance;efficient scaling59|141|3更新时间：2025-07-16
- 摘要：The asymmetrical double-material-gate s-Si (strained Silicon) HALO doping channel MOSFET (Metal-Oxide-Semiconductor Field Effect Transistor) structure is proposed. The front gate and back gate are composed of two metals with different work functions. It has the higher doping concentration in the HALO doping channel end near the drain. The two-dimensional Poisson's equation is solved by applying the parabolic potential approximation and the suitable boundary condition. The analytical models of surface potential、 surface electric field and threshold voltage for the double-material-gate device are constructed by solving which of the front gate and back gate. Results show that the proposed novel device is expected to suppress the short channel effect、hot carrier effect and drain induced barrier lowering. The derived analytical models accord with the DESSIS simulation results very well.关键词：strained Si;HALO doping channel;asymmetrical double-material-gate;short channel effect35|89|0更新时间：2025-07-16
- 摘要：Utilizing short-wave two-dimensional antenna arrays, the HF backscatter sweep frequency-elevation ionogram is obtained for the first time in China. In this paper combining genetic algorithm and Otsu for the signal extraction of the group-frequency-energy three-dimensional ionogram. Using the connected domain marking to eliminate discrete point noise, obtain the clean signal, and use the Canny detetion method to obtain the nearest and farthest distance of each frequency in the echo signal. On the group-frequency-elevation three dimensional ionogram, the elevation-group data of each frequency is acquired, Fitting the points by the polynomial fitting, logarithmic fitting of the elevation and logarithmic fitting of the group, Finally performing error analysis of the fitted curve through the vertical detection data of the Qingdao observation station. The result show that the logarithm of the group obtained curve is in good agreement with the target curve. The validity of the extraction method is proved.关键词：short-wave;two-dimensional arrays;ionogram;elevation;fitting method34|86|2更新时间：2025-07-16
- 摘要：A cognitive signal recognition and demodulation model is designed based on the cyclic neural network for conventional amplitude-phase satellite modulations. Through the cyclic neural unit, the features of the target signal are extracted. And the features are dimension-mapped by the fully connected neural network. The model finally completes the modulation recognition and demodulation of the target signal with these mapped features. This method does not need much prior knowledge about signal-to-noise ratio (S/N), and it is not sensitive to frequency offset. The method also has good adaptability in the maintenance and extension, which conforms to the demands of the engineering, while the traditional algorithms need to redeploy the decision rule. Computer simulations show that the correct recognition probability is close to 98% when S/N is greater than 6 dB and demodulation error rate is close to the theoretical gate. The presented theoretical form provides a new idea for intelligent signal processing, and it can also be used in other communication signal processing fields.188|373|8更新时间：2025-07-16
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