Space-time spectrum sharing based on game theory:dynamic access and penalty strategy by Yangyang NIU, Zhiqing WEI, Zhiyong FENG

“…To tackle the challenge of inefficient utilization of spatiotemporal spectrum resources in heterogeneous networks, a reliable spectrum sharing strategy based on game theory was proposed for scenarios where multiple secondary users dynamically access through sensing spatiotemporal spectrum opportunities.Firstly, secondary users sensed the activity state of primary users through channel sampling and subsequently seek suitable spatiotemporal spectrum opportunities.Each secondary user aimed to access more spectrum resources while preventing quality degradation between primary users.Consequently, a negotiation of individual utilities between secondary and primary users was needed, in order to reach a mixed Nash equilibrium.When the secondary user's transmission power was abnormal, its behavior would be regarded as a violation.Then, a backoff time compensation algorithm was presented to penalize the secondary users, according to the number of violations and active nodes in the network.Finally, simulation results validate the effectiveness of the spatiotemporal spectrum opportunities sharing strategy with the penalty mechanism.…”
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Dynamics Characteristic Analysis of Sliding Bearing-rigid Rotor System with Flexible Support by Wenbin Wang

“…The dynamics behavior of the system is numerically simulated by using the fourth-order variable step size Runge-Kutta algorithm， the displacement bifurcation diagrams of the rigid rotor system varying with rotational speed with different external excitation amplitudes，and the phase diagram and Poincaré map under specific parameters are obtained. …”
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A Generalized Decision-Making Technique Based on Bipolar-Valued Multivague Soft Sets by Hanan H. Sakr, Abdisalam Hassan Muse, Ramy Aldallal

“…Finally, a bipolar-valued multivague soft set-designed decision-making algorithm, as well as a real-life example, are discussed generalizing the Roy and Maji method.…”
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Energy Analysis in Combined Reforming of Propane by K. Moon, Ganesh R. Kale

“…Thermodynamic equilibrium data for combined reforming was generated for temperature range of 400–1000°C at 1 bar pressure and combined oxidant (CO2 + H2O) stream to propane (fuel) ratio of 3, 6, and 9 by employing the Gibbs free energy minimization algorithm of HSC Chemistry software 5.1. Total energy requirement including preheating and reaction enthalpy calculations were done using the equilibrium product composition. …”
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Secondary Intraocular Lens Options in Intraocular Lens Dislocation: A Review by Alexander Maloof, Ava James, Nicholas Pavic, Shane Zhang, Stephanie Wu, Christopher Go

“…We then evaluated the techniques available for each option, with a clinical focus on the anatomical indications, technical considerations, advantages, and potential complications, before proposing an algorithm for determining the selection of each major secondary IOL implantation technique. …”
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Deepfake Dilemmas: Imagine Tomorrow’s Surveillance Society through Three Scenarios by Fatma Doğan Akkaya

“…Moving beyond technical considerations, the research employs social prediction methods to explore three potential future scenarios involving deepfake avatars: seamless integration that facilitates self-expression but complicates digital identity control; pervasive algorithmic surveillance that exacerbates social control and privacy issues; and the concept of ghost avatars, that is, digital representations that function as commodities or tools of resistance. …”
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Numerical Calculations on the Unsteady Aerodynamic Force of the Tilt-Rotor Aircraft in Conversion Mode by Hao Chen

“…The dual time-stepping approach and the finite volume scheme are applied to solve the unsteady N-S equation. A parallel algorithm is utilized in this work to improve the computational efficiency. …”
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Channel-space endogenous anti-jamming method based on multi-reconfigurable intelligent surface by Yonggang ZHU, Yifu SUN, Fuqiang YAO, Cheng LI, Wenlong GUO, Kang AN

“…In view of the concern that the traditional anti-jamming method based on jamming recognition is challenging to defend against both the unknown and the intelligent jamming attacks, a dynamic, heterogeneous, and redundant channel-space anti-jamming technique was proposed by adopting multiple reconfigurable intelligent surface (RIS), which facilitated the exploitation of channels’ resources for combating with the unknown jamming attacks.To elaborate, a channel-space endogenous anti-jamming method was proposed by leveraging the optimization of both the RIS’ coefficients and the multiple RIS’ on-off status.Firstly, after decoupling the tightly coupled variables, the optimal closed-form solutions of transmit precoder, RIS’ coefficients, and receive decoder could be derived under the alternative optimization framework.Then, the greedy algorithm was adopted to optimize the multiple RIS’ on-off status for obtaining better anti-jamming communications, and the convergence and the computation complexity of the proposed method was analyzed.Theoretical analysis and simulation results show that the proposed method can effectively defend against the uncertain jamming attacks.…”
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Iterative rake equalization method for low-complexity OTSM in high-speed mobile environment by Guojun LI, Kun LONG, Changrong YE, Jiawen LIANG

“…Aiming at the problems of poor anti-noise performance and high computational complexity of the existing orthogonal time sequency multiplexing (OTSM) equalization methods, a low-complexity iterative rake equalizer based on maximum ratio combining (MRC) was proposed.The main idea was to use MRC to iteratively extract and coherently combine the received multipath components of the transmitted symbols in the delay-time domain to improve the signal-to-noise ratio of the combined signal.In order to speed up the convergence of the MRC iterative algorithm, a single-tap time-frequency equalizer was designed to provide an initial estimate, and then combined with an external error correction code to further improve the bit error performance.The simulation results show that the performance of the iterative rake equalizer based on MRC is significantly better than that of the LMMSE linear equalizer, and the performance and computational complexity are greatly improved compared with the currently widely used Gauss-Seidel (GS) iterative equalizer.…”
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Kinematics Analysis and Multi-objective Scale Synthesis of a New Three Translation Parallel Mechanism by Jianyuan Liu, Jianlin He, Zhixiong Jian, Junguo Gao

“…Finally，a multi-objective optimization design model is established，with elite retention strategy of rapid and dominate the multi-objective optimization algorithm （NSGA-Ⅱ），the scale synthesis of the structural parameters is carried out，a set of Pareto optimal solutions are obtained by optimization. …”
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Feature Selection Using Particle Swarm Optimization in Intrusion Detection by Iftikhar Ahmad

“…Evolutionary optimization approach like genetic algorithm (GA) has been used to search the most discriminative subset of transformed features. …”
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A Color-Image Encryption Scheme Using a 2D Chaotic System and DNA Coding by Haidar Raad Shakir

“…The results of simulation and security tests reveal that the proposed algorithm offers robust encryption and demonstrates the ability to resist exhaustive, statistical, and differential attacks.…”
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Efficient keyword spotting system for information retrieval by LUO Jun, OU Zhi-jian

“…A new two-stage keyword spotting system was proposed based on syllable graph for audio information retrieval task,which could efficiently spot the interesting words in mass speech data,thus serve for the national security.It comprised two stages – preprocessing and searching.In the preprocessing stage,the audio data was recognized into syllable graph which included high accuracy syllable candidates,and unsupervised MLLR（maximum likelihood linear regression） adaptation was carried out iteratively to further improve the accuracy of the syllable graph.In the searching stage,to answer the frequent queries from users,searching for matched keywords was only scanned in the graph for likely syllable strings.A forward-backward algorithm based on syllable N-grammar was used to calculate confidence measures for further filtering of the searching result.Experimental results show the system achieved good performances in both recall rate and accuracy rate,and in the searching stage only 0.01 times of real time is needed,which can meet the demand for fast retrieval.…”
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A Two-Level Iterative Node Importance Evaluation of Aircraft Function Modules Based on Influence Matrix by Chang Liu, Jinyan Wang, Kangxing Wang

“…The influence matrix was constructed by using the node access probability calculated by the PageRank algorithm and the function module weight calculated based on centrality. …”
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Credible distributed identity authentication system of microgrid based on blockchain by Guanqun YANG, Yin LIU, Hao XU, Hongwei XING, Jianhui ZHANG, Entang LI

“…Most of the blockchain-based identity authentication systems are based on public blockchain, which are still essentially traditional centralized identity management and verification methods, making it difficult to meet the needs of trusted access and fine-grained access control in microgrids.Therefore, based on the FISCO BCOS consortium blockchain technology, a distributed identity authentication system supporting multi-center was designed.A DID-based identity management protocol to achieve autonomous control of user identity in a practical scenarios was designed.Distributed trusted access technology for end nodes in microgrids was studied, and privacy-protecting credentials based on zero-knowledge proof were designed.This scheme meets the requirements of trustworthy and verifiable user identity in different privacy security scenarios, and achieves autonomous control of entity identity, fine-grained access control and trusted data exchange.The usability and effectiveness of the proposed algorithm are demonstrated through system experiments and performance analysis.…”
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Drought Prediction Model of Pearl River Basin Based on SST and Machine Learning by FENG Xin, LIU Yanju, TONG Hongfu, QIAN Shuni

“…Combining with the random forest algorithm, this paper constructs a new meteorological drought forecasting model through regression analysis to screen global SST areas of forecasting significance and takes the Pearl River Basin as an example for application tests. …”
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Rate splitting based robust secure transmission scheme in RIS-assisted satellite-terrestrial integrated network by Bai ZHAO, Min LIN, Shengjie XIAO, Ming CHENG, Yifan FENG, Lvxi YANG

“…Firstly, considering a reconfigurable intelligent surface (RIS) assisted satellite terrestrial integrated network, the satellite employed the rate splitting multiple access technique to serve multiple earth stations in the presence of multiple eavers-droppers(Eves), while the terrestrial network leveraged multicast technique to serve many ground users with the assist of RIS.Secondly, assuming that only the Eves’ imperfect channel state information could be obtained, a joint optimization problem was formulated to minimize the total transmit power, while ensuring the quality-of-service requirement for all users, and adhering to intercept probabilistic constraints.To tackle this noncom vex problem, the S-procedure and the successive convex approximation approach were employed to convert the intercept probabilistic constraints into solved ones.And then a nuclear norm-based penalty function was employed to propose a robust joint algorithm to obtain the robust beamforming weight vectors and transmit power.Finally, the simulation results demonstrate the effectiveness and superiority of the proposed transmission scheme.…”
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Pilot decontamination based on spectrum separation in massive MIMO system by Hairong WANG, Jian DONG, Yuhui WANG

“…In order to overcome uplink pilot contamination，the technical bottleneck of massive MIMO,and different from the existing parallel parameter design strategy for blind pilot decontamination,a hierarchical parameter design method was proposed,which points out that different system parameters have different effects on the exact spectrum separation of the sample covariance matrix of the received signal.In other words,different parameters have different priority.Next,it was found that to achieve spectral separation,the power of the desired signal didn’t have to be higher than the interference,and the difference between the two was more important.Furthermore,in a more practical scenario where the pilot sequence length was less than the number of base station receiving antennas,a numerical algorithm was given for the first time to achieve the above-mentioned exact spectral separation.Since the hierarchical parament design ensures the exact separation of the asymptotic spectrum,the results show that the proposed scheme is more suitable for practical applications than the existing blind pilot decontamination.…”
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Kinematics Modeling and Simulation of Wheel-foot Hybrid Walking Robot by Xinxing Tang, Deyong Zhang, Rui Wang, Chengzhi Su, Fangyuan Han

“…A robot body posture adjustment algorithm is proposed to improve the motion stability of the robot body in a static walking gait. …”
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Study on remote sensing satellites random access to internet constellation and on-orbit intelligent processing by Xiaoyu CHANG, Weijia ZHANG, Xudong1 LI, Xiaonan ZHANG, Gang WANG, Gang JIA

“…The low earth orbit (LEO) satellite Internet constellation is a hot spot in current global research.And it is highly anticipated that the LEO satellite Internet constellation supports random access to remote sensing satellites and direct on-orbit information processing.However, due to the different orbital heights, the difficult access problems of the bidirectional highly dynamic heterogeneous constellation will be caused.Firstly, the random access scenario under different orbit characteristics and satellite numbers of LEO satellite Internet constellation was set up, and the impact of the spatiotemporal discontinuous visibility and Doppler frequency shift on the remote sensing satellite access performance was focused on.Secondly, based on the characteristics of the random access scenario, the process of on-orbit processing tasks with different delays and the allocation of satellite-ground functions were analyzed.Finally, the problems existing in the current on-orbit intelligent processing algorithm and the focus of future research were expounded, so as to provide reliable theoretical support for the development and applications of LEO satellite Internet constellation and remote sensing satellites in the future.…”
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