最新刊期
卷 34 ， 期 6 ， 2006
- 摘要：Phase unwrapping-the key step of interferometric synthetic aperture radar (InSAR) signal processing-is discussed,and a new method is proposed which is based on residues recognition and modified loop-integration.The validity of the new method is verified with the simulated and real data.Finally,a comparison of the processing results for the real data between the modified loop-integration,branch-cut and region-growing is presented,and a comparison of their performance is also given.关键词：phase-unwrapping;loop-integration;branch-cut;region-growing;residue;interferometric synthetic aperture radar (InSAR)2|1290|1更新时间：2025-07-16
- 摘要：A new adaptive maneuvering target tracking algorithm STF-CS is presented based on the "current" statistical model (CS).By introducing a fading factor of Strong Tracking Filter (STF),this algorithm improves the adaptive tracking performance greatly when there is a sudden maneuver,and has the same high precision to track common maneuvering targets as the "current" statistical model and adaptive tracking algorithm.Simulation results show that,when there is only common maneuver the performance of the two algorithms is the same,when there is a sudden maneuver,the performance of STF-CS is much better than the CS.关键词：maneuvering target tracking;"current" statistical model;strong tracking filter;Kalman filter2|1249|25更新时间：2025-07-16
- 摘要：The signal fusion of multiple frequency bands and multiple radars is an effective method to improve the resolution of target range profile.With the sparse band observation,the conventional phase compensation methods in signal fusion are invalid because the frequency bands are sparse.A new super-resolution range imaging method based on the modified MUSIC (multiple signal classification) algorithm is presented with liner frequency modulated signal.Firstly,the uniform B-splines is applied to resample the signals for obtaining the uniform signal sequences.Secondly,the signal model of multiple radars with multiple frequency bands is established.Consequently,the phase compensation parameter and the scatter center parameters are estimated based on the uniform signal model.The theoretical analysis and simulations results show the presented signal fusion imaging method can effectually increase signal bandwidth and obtain super-resolution range image under sparse frequency band observations conditions.关键词：signal fusion;liner frequency modulated;super-resolution;Multiple Signal Classification(MUSIC)2|1499|9更新时间：2025-07-16
- 摘要：The passive direction finding cross location method is widely adopted in the passive localization,therefore there will exist masses of false intersection points.Eliminating these false intersection points correctly and quickly is a key technique in passive localization.A new method is proposed for passive locating and tracking multi-jammer target.It not only solves the difficulty to determine the targets number under the existence of masses of false intersection points,but also solves the initialization problem of elastic network. Thus this method solves the multi-jammer target correlation and the elimination of static false intersection points.The method which dynamically establishes the multi-supposition track tree solves elimination of remaining false intersection points.Simulation results show that computation burden of the method is lower,the elastic net has more fast convergence velocity and more high rate of locking the true targets and the method can eliminate more false intersection points.关键词：passive locating and tracking;data clustering;elastic net;false intersection points4|1094|17更新时间：2025-07-16
- 摘要：Basis Pursuit is a novel method of signal sparse representation.It seeks sparse representation from over-complete dictionaries.That is to use the fewest dictionary elements to represent the signal exactly.Then the intrinsic feature of the signal can be captured.We extend the application of the Basis Pursuit method to SAR super-resolution processing.Firstly,based on the SAR attributed scattering model,a new type compacted Dictionary is designed in phase history domain.By this way,the dimension of the desired problem is even smaller.Secondly,a new and fast iterative algorithm is proposed,the fine feature parameter estimation of the scatter in SAR image is obtained.Finally,in terms of SAR attributed scattering model in the phase history domain,larger scale phase history data is built.By FFT imaging,higher resolution image is obtained.Simulation experiments and computational results of measured MSTAR data demonstrate that Basis Pursuit can be implemented speedy and stably,it can provide super-resolution at the same time.关键词：SAR images;super-resolution;basis pursuit;dictionary3|1086|5更新时间：2025-07-16
- 摘要：In order to obtain a UAV SAR image of high quality,a method is proposed to compensate the motion errors of UAV by virtue of the analysis of its motion errors.In our method the attitude errors are compensated through an antenna servo system.Based on the established error model the position errors are estimated by the instantaneous Doppler chirp rate from the SAR raw data and compensated through the envelope correction and the phase correction of the raw data,respectively.The experiment results show that the proposed approach can get the high quality SAR image from the UAV SAR raw data.关键词：synthetic aperture radar (SAR);unmanned aerial vehicle (UAV);motion compensation;instantaneous Doppler chirp rate6|1819|9更新时间：2025-07-16
- 摘要：A novel weaken signal detecting and frequency estimating blindly algorithm (LSFD) based on period-time-average is proposed according to the cyclostationary under stronger interference.LSFD algorithm can estimate signal frequency correctly,and restrict interference and noise effectively than FFT.The analysis and simulation results show that LSFD algorithm is blindly,and faster than correlation method.关键词：colored noise;almost cyclo-stationary;period-time-average;cyclo-frequency;asymptotic convergence2|843|0更新时间：2025-07-16
- 摘要：Quadric difference frequency needs more frequencies to range longer distance or to range more precisely under fixed SNR.The requirements of SNR to range correctly and the relationship between SNR and precision have been deduced in detail.Then a new method - combination frequency difference is proposed,which improves the performance of ranging under the same number of frequencies and the same condition.Finally simulated results verify the validity of the method.关键词：multiple frequencies ranging;quadric difference;signal noise ratio;combination frequency difference2|1068|2更新时间：2025-07-16
- 摘要：A new three-stage beamformer is proposed for reception of coherent signals with the assumption that the directions-of-arrivals (DOA's) of the uncorrelated interferers have been estimated a priori.First,the estimated DOA's of the uncorrelated interferers are used to construct a transformation matrix.Secondly,the composite vector of the coherent sources is estimated based on the transformation matrix.Finally,using the estimated composite vector and the array correlation matrix,adaptive beamforming is performed.Experimental results show that the proposed beamformer almost achieves the optimum performance and rapidly converges.关键词：beamforming;array processing;coherent signals2|882|1更新时间：2025-07-16
- 摘要：The topic of instantaneous measurement of radar target polarization characteristics is of great importance in such fields as polarimetric radar and target recognition.In this paper,the problem of polarization scattering matrix measurement of the reciprocal target is discussed for the case of frequency-shifted waveforms.Radar echoes are modeled for the instantaneous polarization measurement.On the basis of target returns’ polarization characteristics,a frequency-domain estimate algorithm is presented for the instantaneous polarization measurement using the discrete time Fourier transform (DTFT).Algorithm performance is evaluated and theoretical formulae are derived.Efficiency of this algorithm is validated by experiment results.关键词：polarimetric radar;target;polarization scattering matrix;reciprocity;instantaneous measurement;frequency shifted waveforms2|1671|28更新时间：2025-07-16
- 摘要：Based the background of multiple targets in a tracking monopulse radar’s mainbeam and the durative for targets staying in the mainbeam,a new detecting method is put forward,which combine the Generalized Likelihood Ratio Test (GLRT) with sequential register.The analysis in theory is executed by using the classical probability knowledge.The results of analysis and the simulation show that the new method can provide higher detecting probability for multiple targets than GLRT method does.关键词：monopulse radar;multiple targets;Generalized Likelihood Ratio Test (GLRT);sequential register2|1274|5更新时间：2025-07-16
- 摘要：A beamforming model of multi-beam direct-radiating array antenna is established.A modified complex-coded genetic algorithm is introduced.This genetic algorithm chooses different mating operator in different period of time.It selects different crossover operator such as extrapolation,interpolation,and orthogonal direction extrapolation and interpolation crossover operator in different generation.This algorithm overcomes the disadvantages of existing genetic algorithms — prematurity and the dependence of convergence on the initial population,and enhances global convergence performance of the algorithm.It uses "remember operator" to suppresses the DOA-hop jamming.Computer simulation shows that this method has the advantages of high resolution and reliability in LEO satellite beam-space adaptive nulling.Its anti-jamming ability is better than the traditional adaptive beamforming algorithms.关键词：genetic algorithm(GA);adaptive beam-forming;LEO satellite;direct-radiating array2|1039|2更新时间：2025-07-16
- 摘要：Constrained least-square design of two-dimensional quadrantally symmetric linear-phase FIR filters is formulated as minimizing the total squared approximation error subject to specified passband and stopband ripples.A projected least-square algorithm that alternatively updates the active set of constraint and projects the unconstrained minimal point successively onto the boundary of the active constraints is presented.Applications in the design of circular and diamond-shaped low-pass FIR filters demonstrate that the algorithm is much more efficient than an active-set based algorithm and an interior-point based algorithm.关键词：two-dimensional FIR filter;constrained least-square problem;projected least-square algorithm2|664|2更新时间：2025-07-16
- 摘要：Transparency of the fingerprinting is one of important requirements for electronic exchange to achieve the protection of multimedia content assuming the purchaser may not know the existence of fingerprinting.In terms of the security format for two's Complement fixed-point numbers and additive homomorphic cryptosystem,this paper proposes an asymmetric fingerprinting scheme based on spread-spectrum coding.The analysis shows that the scheme provides many advantages,such as purchase transparency,absent trial,no-repudiation and no-framing and so on.关键词：digital fingerprinting;asymmetric fingerprinting;tracing traitor;spread spectrum code;additive homomorphism2|857|2更新时间：2025-07-16
- 摘要：There has much influence of the image complexity on vision feeling,while less work has been done in complexity definition.A sound complexity notion is defined according to the information entropy using runlengh measure method.In order to give a quantificationally analysis of complexity,the runlength probability distribution of random sequence is deduced.The adjacency degree between the runlength probability distribution of image plane and that of random sequence is used to describe the complexity.关键词：information hiding;image bit-plane;complexity2|1035|12更新时间：2025-07-16
- 摘要：Based on the given structural model of distributed web server system,a new dynamic load balancing algorithm which is periodic update and in which both static content and dynamic content are included is proposed.Through the result gained by loading the given algorithm on the founded emulated flat,the conclusion that the algorithm can balance the system load effectively is received.关键词：load balancing algorithm;distributed web server;dynamic load balance2|642|3更新时间：2025-07-16
- 摘要：An efficient H.264 bit rate transcoding scheme based on PID controller,is proposed in this paper.In the scheme,simplified cascaded pixel domain transcoding structure is adopted to reduce the computational complexity while remaining the reconstructed video quality.Furthermore,a PID controller is introduced in the picture layer to ensure the output bit rate consistent with the target bit rate.The experimental results show that,the scheme proposed in the paper can achieve high bit rate accuracy,which is an efficient bit rate transcoding scheme.关键词：transcoding;bit-rate transcoding;rate control;H.2642|984|1更新时间：2025-07-16
- 摘要：k homomorphic mappings from k-ary n-stage de Bruijn-Good graph onto k-ary(n-1)-stage de Bruijn-Good graph are defined.By using the homomorphic mappings,we prove a relational theorem between n-stage nonsingular feedback function f(x1,x2,…,xn) and (n-1)-stage nonsingular feedback function g(x1,x2,…,xn-1),whose state graph is Da(Gf),and give an algorithm for generating k-ary feedback functions of n-stage de Bruijn sequences from those of (n-1)-stage de Bruijn sequences.In particular,when k=2 and a=0,by using the simplicity of mapping D over Z 2,we give an effictive algorithm for generating n-stage feedback functions of de Bruijn sequences from (n-2r)-stage the feedback functions,where r is a nature number.关键词：de Bruijn-Good praph;de Bruijn sequence;homomophic mapping;nonsingular feedback function2|1119|11更新时间：2025-07-16
- 摘要：The housekeeping processing is usually performed to optimize the I/O costs of spatial join refinement step.The problems in housekeeping phase have been shown NP-hard,and most methods solve them with high computation complexity.We reduce the page-clustering problem and cluster-sequencing problem to k-way partition and maximum length of graph respectively,and solve the problems with improved genetic algorithm and approximation algorithm based on maximum-span-tree.To satisfy the constraint of page cluster partition,we make some correction on the classical genetic algorithm.The solution of approximation algorithm is greater than half of optimal solution.Theoretical analysis and simulation experiment shows the feasibility and effectiveness.关键词：spatial join;refinement step;housekeeping;genetic algorithm2|808|1更新时间：2025-07-16
- 摘要：The difference field RCS (d-RCS) has been defined to analyze the scattering from the target above a rough surface.In this paper,the electric field integral equations (EFIE) of the difference induced current on the rough surface and the induced current on the target are derived.An iterative approach is developed to solving the two EFIEs and scattering from both the target and underlying surface.How to choose the illuminated length of the rough surface for numerical iterations is discussed.Using the Monte Carlo method to realize the ocean-like rough surface,bistatic scatterings from the target,e.g.a cylinder or a square column,above a P-M (Pierson-Morkowitz spectrum) rough oceanic surface are numerically simulated for TE tapered wave incidence.Difference bistatic scattering of a square column above rough surface shows multi-peaks in different directions related to the spatial orientation and geometry of the square column.关键词：target and rough surface;bistatic difference scattering;iterations and numerical simulation2|1368|6更新时间：2025-07-16
- 摘要：The scattering of electromagnetic waves from Frequency Selective Surface (FSS) supported by both electrically and magnetically anisotropic substrates is investigated by using Galerkin’s method in the spectral domain.The analytical procedure is introduced and Spectral Green’s function for the considered structure is formulated based on Maxwell’s equations directly.A series of FSS with different medium parameters are computed efficiently,These results reflect the influence of the electrical and magnetic anisotropy on the electromagnetic characteristics of FSS.关键词：frequency selective surfaces(FSS);anisotropy;spectral domain method2|902|0更新时间：2025-07-16
- 摘要：As a crucial step in content-based news video indexing and retrieval system,shot boundary detection attracts much more research interests in recent years.To partition news video into shots,many metrics were constructed to measure the similarity among video frames based on all the available video features.However,too many features will reduce the efficiency of the shot boundary detection.Therefore,it is necessary to perform feature reduction for the decision rules of shot boundary.For this purpose,the classification method based on rough-fuzzy sets for feature reduction and the dissimilarity function is proposed.Finally,for each given class,the fuzzy if-then rule is generated for decision with fuzzy inference.The efficacy of the proposed method is extensively tested on more than 3 hour of CCTV news programs and 95.4% recall with 96.1% precision have been achieved.关键词：shot boundary detection;Rough-Fuzzy set;Rough-Fuzzy operator;feature reduction;dissimilarity function2|1033|10更新时间：2025-07-16
- 摘要：Integral Imaging (II) is a technique capable of displaying three-dimensional images with continuous parallax in full natural color.Since micro-lens sheet is used in recording,only one recording is necessary in containing three-dimensional information.This paper introduced the technology of II and presented a method of extracting depth information directly from lenticular II images with a modified-multiple-baseline algorithm.The results not only can provide fundamental for data processing of the next generation II-based 3D TV,but also can be used as a novel depth measurement methodology.关键词：integral imaging;depth measurement;stereo matching;multiple-baseline;disparity analysis2|1429|3更新时间：2025-07-16
- 摘要：Perceptual constancy is the most salient aspect of the way the world looks to us.It may enlighten some new ideas for many open issues of computer vision,such as automatic image understanding and image object recognition.Size constancy is one of the most important perceptual constancy.The key to correct size constancy perception of image object is to correctly estimate the depth of objects in the image.This paper introduces most of image depth cues used by human vision,and presents a method to resolve the fusion and confliction of these cues.Then we propose a model to implement size constancy computation of image objects.Experimental results suggest that our model can work reasonably well.In addition,this paper sets a good example for applying visual psychology to resolving computer vision problems.关键词：size constancy;visual psychology;image understanding;image depth cue2|2672|1更新时间：2025-07-16
- 摘要：The time-domain electric,magnetic and combined field integral equations (TDEFIE,TDMFIE and TDCFIE) have been applied widely to the analysis of transient scattering from conducting bodies.The marching-on-in-time (MOT) schemes,relying on suitable spatial integral rules and implicit time-stepping method,for solving the TDCFIE and TDMFIE have been found to be stable.Unfortunately,the same is not true for the TDEFIE.In this article,the non-singular integral is evaluated using the standard Gaussian quadrature rules,and the transformations of the parametric coordinates and plane polar coordinates are employed to transform the singular integrals of TDEFIE into non-singular integrals,which can be accurately and efficiently evaluated by dividing the original domain of integration into sub-domains.Simulation results demonstrate that this approach produces rather stable and more accurate results without resort to any averaging processes.In addition,this method suits to any temporal basis functions and can be extended to high-order spatial basis functions.关键词：time-domain integral equation;electromagnetic transient scattering;marching-on-in-time method;singular integrations4|1223|4更新时间：2025-07-16
- 摘要：Ant colony algorithm is a brand-new type of simulative evolution algorithm,which focus on its solution to conform optimized question.The author utilizes this algorithm to optimize PID control parameter,but in basic ant colony algorithm,there are some defects of slow convergence speed,easy to get stagnate,and low ability of full search.This paper presents a method of optimized PID control of self-adapted ant colony algorithm based on genetic gene and design out the parameter optimized diagram.This method not only overcomes the shortage of basic ant colony algorithm,but also perfectly realizes the optimization of PID control parameter.Compared to the result of simulation with Z-N optimization,genetic algorithm and basic ant colony algorithm,results of optimization can be greatly improved.The experiments show that this method has its practical value on controlling other objection and process.关键词：genetic gene;ant colony algorithm;information element;PID control6|1535|10更新时间：2025-07-16
- 摘要：Multicast service with Quality of Service (QoS) guarantees is critical to many real-time multimedia internet applications.The QoS-aware multicast routing protocols should have the ability to find a sourced-based tree with the end to end QoS bounds and the minimal network resource consuming.The Delay Constrained Steiner Tree problem (DCST) is one of the key issues.We present the Branch Optimization algorithm for DCST.The core of our algorithm called Reverse Branch Adjusting Procedure (RBAP) is proposed to adjust the paths violating the delay constraint at the same time keep the modification to the spanning tree as little as possible.The simulation shows that our algorithm is efficient for actual networks.关键词：QoS routing;Steiner tree;multicast;bifurcate node2|697|0更新时间：2025-07-16
- 摘要：When multiple targets in formation are in the observation region,the return signals from these targets may be overlapped both in the range and Doppler domain.Thus,it is difficult to separate these targets from each other,and each individual target cannot be clearly imaged.A new implementation method of ISAR imaging is proposed for multiple targets in formation.After radial acceleration compensation and Keystone transformation are performed,range alignment is accomplished for all moving targets.When multiple targets are moving smoothly,the Doppler variation of subechoes from scatterers can be approximated as a first-order polynomial.Therefore,the modified Chirp-Fourier transform combined with the CLEAN technique is applied to each range cell to obtain the cross-range profiles of multiple targets simultaneously.The imaging results obtained by using simulated data show the effectiveness of the proposed method.关键词：inverse synthetic aperture radar;multiple targets;Keystone transformation;modified discrete Chirp-Fourier transform2|873|3更新时间：2025-07-16
- 摘要：A experimental system of a wideband optically controlled phased array antenna is presented.The paper will cover the system design and performance of an S-band 96-element array controlled by photonics.The wideband performance of the system will be highlighted.The 5-bit photonic time-delay unit based on RF switch afford wide instantaneous bandwidth.The test array patterns show no beam squints over 2.5 to 3.5 GHz range.关键词：true-time-delay;optically controlled phased array;antenna3|1486|2更新时间：2025-07-16
- 摘要：We present a method for preserving time-invariant phase relationships,through introduce a third signal as a reference,when ratios are taken between two complex signals that are harmonically related.We prove that the theory taking fundamental signal as a reference to be able to eliminate the phase ambiguity is effective.After that we provide a simple example to illustrate this conclusion and show how to apply this technique when calculating nonlinear large-signal scattering function.In the practical application this algorithm manifests to have a broad application prospect.关键词：calculating ratios;harmonically related;phase ambiguity;nonlinear large-signal scattering function2|979|1更新时间：2025-07-16
- 摘要：Ground moving target indicator (GMTI) using space-based sparse array is attractive.How to estimate the clutter rank simply and accurately is an essential issue in space time adaptive processing (STAP) Space-based sparse arrays usually appear as subarrays or arrays with non-isotropic elements.The 2D space time signal can be viewed as 1D space signal received from an equivalent synthetic space array according to space time equivalence theory.Then simple and accurate clutter rank estimating formulas are derived from the synthetic space array according to these two classes of sparse array.The simulations verify the accuracy of the formulas.Basic design constraints of the distributed small satellite based GMTI radar are derived from the clutter rank.关键词：sparse array;space time adaptive processing;radar clutter;clutter rank;ground moving target indicator2|859|2更新时间：2025-07-16
- 摘要：Relationship between the target scattering function and the echo signal is deduced to hold as a Fourier transform pair by analyzing the texture of echo signal for a passive radar imaging system;then an algorithm is presented,which makes use of multiple receivers to form a synthetic aperture for passive radar imaging in the case of single external illuminator available.Due to collected data is non-uniform and sparse in Fourier space,the presented algorithm processes data in polar grid format,which can make full use of original precise data,so the quality of final image is improved.Theory derivation and computer simulation confirm the effectiveness of the proposed algorithm.关键词：passive radar imaging;synthetic aperture;mode of single illuminator and multiple receivers2|631|13更新时间：2025-07-16
- 摘要：Multi-objective chaotic evolutionary algorithm (MCEA) is designed.In each generation of MCEA,after the population finishes all genetic operations and external archive maintenance is done,chaotic search is performed on the copy of several individuals randomly chosen from the external archive to obtain new non-dominated solutions.MCEAs respectively merging strength Pareto evolutionary algorithm (SPEA),SPEA2 with chaotic search based on Logistic map are applied to some complex multi-objective optimization problems.The computational results demonstrate that the comprehensive performance of multi-objective evolutionary algorithm (MOEA) is improved as a consequence of the inclusion of chaos.关键词：chaos;pareto optimal;multi-objective evolutionary algorithm2|1053|19更新时间：2025-07-16
- 摘要：An accurate and efficient method for computing Sommerfeld type integrals is crucial in the analysis of the electromagnetic waves for radiators and scatters in the presence of a conducting half-space.In this paper,an analytical approach is described for the evaluation of the Hertz potential of a vertical magnetic dipole over the finitely conducting medium plane.By using the expansion of spherical wave functions for a cylindrical wave function and the techniques of the hypergeometric functions,the Sommerfeld integral contained in the potential is expressed as a rapidly and absolutely convergent series of spherical wave functions;and the coefficients of the series are cast into the Legender polynomials with complex argument for the medium parameter.The obtained result has the advantage that it holds without the restrictions on the locations of dipole source and observation points,ranges of medium parameters and frequency and so on,and can conveniently be employed to calculate and analyze the electromagnetic fields.关键词：electromagnetic theory;Sommerfeld type integral;vertical magnetic dipole;expansion of spherical wave function2|1170|2更新时间：2025-07-16
- 摘要：A kind of single power supply transimpedance preamplifier (TIA) for optical receiver is developed,using 0.5 μ m GaAs PHEMT process.The TIA has a measured -3 dB bandwidth of 9.5GHz,with transimpedance gain of 43.5±1.5dB Ω in the range of 50MHz~7.5GHz.The return losses of input and output ports are both less than -10dB.The noise figure (NF) varies from 4dB to 6.5dB within the bandwidth,while the calculated minimal equivalent input noise current density is about 17.6pA/ Hz .The measured output eye diagram for 12Gb/s NRI pseudorandom binary sequence is clear and satisfying.关键词：PHEMT;transimpedance;preamplifier2|780|2更新时间：2025-07-16
- 摘要：The design and optimization of integrated circuits (IC) often need the direct and simple relation of the parameters with specifications,called the IC metamodel.The method of design of experiment (DOE) integrated with computer simulation is used to construct the IC metamodel.The 4 experimental design types and 3 models that are applied in the construction of the metamodel are discussed.Through constructing the metamodel of static power that is the main specification of a Low－power integrated operational amplifier,it is found that the method of Latin hypercube sampling integrated with Kriging modeling can provide the most accurate approximation model based on the model error analysis.关键词：integrated circuit metamodel;design of experiment;latin hypercube sampling;kriging modeling2|961|3更新时间：2025-07-16
- 摘要：Workflow technology is a hotspot in the area of computer application,and the efficient modeling methods and application tools are important for workflow system,and are the emphases of research for researchers.Based on the Petri Nets modeling techniques,the workflow model of multi-cases having same characters be studied in this paper.Some properties of the multi-cases workflow net(MCWF-net) are analyzed and verified.Some shortages and errors in before some studied results be covered or rectified.Based on home state,a necessary and sufficient condition for the soundness of the multi-cases workflow net is presented.The results give a new method for workflow system analysis and verification,and it is important to analyze the ability to deal with the business process of workflow system,and improve the efficiency for workflow system to deal with the business process.关键词：Petri net;home state;workflow;multi-cases workflow model;soundness2|863|4更新时间：2025-07-16
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