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Identification of an immune-related gene signature for predicting prognosis and immunotherapy efficacy in liver cancer via cell-cell communication
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作者 Jun-Tao Li Hong-Mei Zhang +1 位作者 Wei Wang Dong-Qing Wei 《World Journal of Gastroenterology》 SCIE CAS 2024年第11期1609-1620,共12页
BACKGROUND Liver cancer is one of the deadliest malignant tumors worldwide.Immunotherapy has provided hope to patients with advanced liver cancer,but only a small fraction of patients benefit from this treatment due t... BACKGROUND Liver cancer is one of the deadliest malignant tumors worldwide.Immunotherapy has provided hope to patients with advanced liver cancer,but only a small fraction of patients benefit from this treatment due to individual differences.Identifying immune-related gene signatures in liver cancer patients not only aids physicians in cancer diagnosis but also offers personalized treatment strategies,thereby improving patient survival rates.Although several methods have been developed to predict the prognosis and immunotherapeutic efficacy in patients with liver cancer,the impact of cell-cell interactions in the tumor microenvir-onment has not been adequately considered.AIM To identify immune-related gene signals for predicting liver cancer prognosis and immunotherapy efficacy.METHODS Cell grouping and cell-cell communication analysis were performed on single-cell RNA-sequencing data to identify highly active cell groups in immune-related pathways.Highly active immune cells were identified by intersecting the highly active cell groups with B cells and T cells.The significantly differentially expressed genes between highly active immune cells and other cells were subsequently selected as features,and a least absolute shrinkage and selection operator(LASSO)regression model was constructed to screen for diagnostic-related features.Fourteen genes that were selected more than 5 times in 10 LASSO regression experiments were included in a multivariable Cox regression model.Finally,3 genes(stathmin 1,cofilin 1,and C-C chemokine ligand 5)significantly associated with survival were identified and used to construct an immune-related gene signature.RESULTS The immune-related gene signature composed of stathmin 1,cofilin 1,and C-C chemokine ligand 5 was identified through cell-cell communication.The effectiveness of the identified gene signature was validated based on experi-mental results of predictive immunotherapy response,tumor mutation burden analysis,immune cell infiltration analysis,survival analysis,and expression analysis.CONCLUSION The findings suggest that the identified gene signature may contribute to a deeper understanding of the activity patterns of immune cells in the liver tumor microenvironment,providing insights for personalized treatment strategies. 展开更多
关键词 Liver cancer cell-cell communication Gene signature PROGNOSIS IMMUNOTHERAPY Single-cell RNA sequencing
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The known,unknown,and unknown unknowns of cell-cell communication in planarian regeneration
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作者 Jia-Jia Chen Kai Lei 《Zoological Research》 SCIE CSCD 2023年第5期981-992,共12页
Planarians represent the most primitive bilateral triploblastic animals.Most planarian species exhibit mechanisms for whole-body regeneration,exemplified by the regeneration of their cephalic ganglion after complete e... Planarians represent the most primitive bilateral triploblastic animals.Most planarian species exhibit mechanisms for whole-body regeneration,exemplified by the regeneration of their cephalic ganglion after complete excision.Given their robust whole-body regeneration capacity,planarians have been model organisms in regenerative research for more than 240 years.Advancements in research tools and techniques have progressively elucidated the mechanisms underlying planarian regeneration.Accurate cell-cell communication is recognized as a fundamental requirement for regeneration.In recent decades,mechanisms associated with such communication have been revealed at the cellular level.Notably,stem cells(neoblasts)have been identified as the source of all new cells during planarian homeostasis and regeneration.The interplay between neoblasts and somatic cells affects the identities and proportions of various tissues during homeostasis and regeneration.Here,this review outlines key discoveries regarding communication between stem cell compartments and other cell types in planarians,as well as the impact of communication on planarian regeneration.Additionally,this review discusses the challenges and potential directions of future planarian research,emphasizing the sustained impact of this field on our understanding of animal regeneration. 展开更多
关键词 PLANARIANS Stem cells REGENERATION Cell communication
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Meiotic transcriptional reprogramming mediated by cell-cell communications in humans and mice revealed by scATACseq and scRNA-seq
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作者 Hai-Quan Wang Xiao-Long Wu +6 位作者 Jing Zhang Si-Ting Wang Yong-Juan Sang Kang Li Chao-Fan Yang Fei Sun Chao-Jun Li 《Zoological Research》 SCIE 2024年第3期601-616,共16页
Meiosis is a highly complex process significantly influenced by transcriptional regulation.However,studies on the mechanisms that govern transcriptomic changes during meiosis,especially in prophase I,are limited.Here,... Meiosis is a highly complex process significantly influenced by transcriptional regulation.However,studies on the mechanisms that govern transcriptomic changes during meiosis,especially in prophase I,are limited.Here,we performed single-cell ATAC-seq of human testis tissues and observed reprogramming during the transition from zygotene to pachytene spermatocytes.This event,conserved in mice,involved the deactivation of genes associated with meiosis after reprogramming and the activation of those related to spermatogenesis before their functional onset.Furthermore,we identified 282 transcriptional regulators(TRs)that underwent activation or deactivation subsequent to this process.Evidence suggested that physical contact signals from Sertoli cells may regulate these TRs in spermatocytes,while secreted ENHO signals may alter metabolic patterns in these cells.Our results further indicated that defective transcriptional reprogramming may be associated with non-obstructive azoospermia(NOA).This study revealed the importance of both physical contact and secreted signals between Sertoli cells and germ cells in meiotic progression. 展开更多
关键词 Single-cell RNA-seq Single-cell ATAC-seq Spermatogenesis Meiosis Transcriptional reprogramming cell-cell communication
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Distinct mononuclear diploid cardiac subpopulation with minimal cell-cell communications persists in embryonic and adult mammalian heart 被引量:1
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作者 Miaomiao Zhu Huamin Liang +6 位作者 Zhe Zhang Hao Jiang Jingwen Pu Xiaoyi Hang Qian Zhou Jiacheng Xiang Ximiao He 《Frontiers of Medicine》 SCIE CSCD 2023年第5期939-956,共18页
A small proportion of mononuclear diploid cardiomyocytes(MNDCMs),with regeneration potential,could persist in adult mammalian heart.However,the heterogeneity of MNDCMs and changes during development remains to be illu... A small proportion of mononuclear diploid cardiomyocytes(MNDCMs),with regeneration potential,could persist in adult mammalian heart.However,the heterogeneity of MNDCMs and changes during development remains to be illuminated.To this end,12645 cardiac cells were generated from embryonic day 17.5 and postnatal days 2 and 8 mice by single-cell RNA sequencing.Three cardiac developmental paths were identified:two switching to cardiomyocytes(CM)maturation with close CM–fibroblast(FB)communications and one maintaining MNDCM status with least CM–FB communications.Proliferative MNDCMs having interactions with macrophages and non-proliferative MNDCMs(non-pMNDCMs)with minimal cell–cell communications were identified in the third path.The non-pMNDCMs possessed distinct properties:the lowest mitochondrial metabolisms,the highest glycolysis,and high expression of Myl4 and Tnni1.Single-nucleus RNA sequencing and immunohistochemical staining further proved that the Myl4^(+)Tnni1+MNDCMs persisted in embryonic and adult hearts.These MNDCMs were mapped to the heart by integrating the spatial and single-cell transcriptomic data.In conclusion,a novel non-pMNDCM subpopulation with minimal cell–cell communications was unveiled,highlighting the importance of microenvironment contribution to CM fate during maturation.These findings could improve the understanding of MNDCM heterogeneity and cardiac development,thus providing new clues for approaches to effective cardiac regeneration. 展开更多
关键词 mononuclear diploid cardiomyocytes cell-cell communication cardiac fibroblast single-cell RNA sequencing cardiac regeneration
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In situ probing of cell-cell communications with surface- enhanced Raman scattering (SERS) nanoprobes and microfluidic networks for screening of immunotherapeutic drugs 被引量:4
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作者 Lei Wu Zhuyuan Wang +4 位作者 Yizhi Zhang Jiayuan Fei Hui Chen Shenfei Zong Yiping Cui 《Nano Research》 SCIE EI CAS CSCD 2017年第2期584-594,共11页
Discovering novel drugs for cancer immunotherapy requires a robust in vitro drug screening platform that allows for straightforward probing of cell-ceil communications. Here, we combined surface-enhanced Raman scatter... Discovering novel drugs for cancer immunotherapy requires a robust in vitro drug screening platform that allows for straightforward probing of cell-ceil communications. Here, we combined surface-enhanced Raman scattering (SERS) nanoprobes with microfluidic networks to monitor in situ the cancer-immune system intercellular communications. The microfluidic platform links up immune cells with cancer cells, where the cancer-cell secretions act as signaling mediators. First, gold@silver core--shell nanorods were employed to fabricate SERS immunoprobes for analysis of the signaling molecules. Multiple cancer secretions in a tumor microenvironment were quantitatively analyzed by a SERS-assisted three-dimensional (3D) barcode immunoassay with high sensitivity (1 ng/mL). Second, in an on-chip cell proliferation assay, multiple immunosuppressive proteins secreted by cancer cells were found to inhibit activation of immune cells, indicating that the platform simulates the physiological process of cancer-immune system communications. Furthermore, potential drug candidates were tested on this platform. A quantitative SERS immunoassay was performed to evaluate drug efficacy at regulating the secretion behavior of cancer cells and the activity of immune cells. This assay showed the suitability of this platform for in vitro drug screening. It is expected that the fully integrated and highly automated SERS-microfluidic platform will become a powerful analytical tool for probing intercellular communications and should accelerate the discovery and clinical validation of novel druKs. 展开更多
关键词 cell-cell communication microfluidic chip surface-enhanced Raman scattering (SERS) barcode immunoassay drug discovery
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Communication Resource-Efficient Vehicle Platooning Control With Various Spacing Policies 被引量:2
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作者 Xiaohua Ge Qing-Long Han +1 位作者 Xian-Ming Zhang Derui Ding 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2024年第2期362-376,共15页
Platooning represents one of the key features that connected automated vehicles may possess as it allows multiple automated vehicles to be maneuvered cooperatively with small headways on roads. However, a critical cha... Platooning represents one of the key features that connected automated vehicles may possess as it allows multiple automated vehicles to be maneuvered cooperatively with small headways on roads. However, a critical challenge in accomplishing automated vehicle platoons is to deal with the effects of intermittent and sporadic vehicle-to-vehicle data transmissions caused by limited wireless communication resources. This paper addresses the co-design problem of dynamic event-triggered communication scheduling and cooperative adaptive cruise control for a convoy of automated vehicles with diverse spacing policies. The central aim is to achieve automated vehicle platooning under various gap references with desired platoon stability and spacing performance requirements, while simultaneously improving communication efficiency. Toward this aim, a dynamic event-triggered scheduling mechanism is developed such that the intervehicle data transmissions are scheduled dynamically and efficiently over time. Then, a tractable co-design criterion on the existence of both the admissible event-driven cooperative adaptive cruise control law and the desired scheduling mechanism is derived. Finally, comparative simulation results are presented to substantiate the effectiveness and merits of the obtained results. 展开更多
关键词 Automated vehicles constant time headway spacing constant spacing cooperative adaptive cruise control event-triggered communication vehicle platooning
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Distributed Nash Equilibrium Seeking Strategies Under Quantized Communication 被引量:1
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作者 Maojiao Ye Qing-Long Han +2 位作者 Lei Ding Shengyuan Xu Guobiao Jia 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2024年第1期103-112,共10页
This paper is concerned with distributed Nash equi librium seeking strategies under quantized communication. In the proposed seeking strategy, a projection operator is synthesized with a gradient search method to achi... This paper is concerned with distributed Nash equi librium seeking strategies under quantized communication. In the proposed seeking strategy, a projection operator is synthesized with a gradient search method to achieve the optimization o players' objective functions while restricting their actions within required non-empty, convex and compact domains. In addition, a leader-following consensus protocol, in which quantized informa tion flows are utilized, is employed for information sharing among players. More specifically, logarithmic quantizers and uniform quantizers are investigated under both undirected and connected communication graphs and strongly connected digraphs, respec tively. Through Lyapunov stability analysis, it is shown that play ers' actions can be steered to a neighborhood of the Nash equilib rium with logarithmic and uniform quantizers, and the quanti fied convergence error depends on the parameter of the quan tizer for both undirected and directed cases. A numerical exam ple is given to verify the theoretical results. 展开更多
关键词 CONSENSUS distributed Nash equilibrium seeking projected gradient play quantized communication
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New insights into cell-cell communications during seed development in flowering plants
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作者 Wei Wang Hanxian Xiong +2 位作者 Kaiting Sun Bo Zhang Meng-Xiang Sun 《Journal of Integrative Plant Biology》 SCIE CAS CSCD 2022年第2期215-229,共15页
The evolution of seeds is a major reason why flowering plants are a dominant life form on Earth.The developing seed is composed of two fertilization products,the embryo and endosperm,which are surrounded by a maternal... The evolution of seeds is a major reason why flowering plants are a dominant life form on Earth.The developing seed is composed of two fertilization products,the embryo and endosperm,which are surrounded by a maternally derived seed coat.Accumulating evidence indicates that efficient communication among all three seed components is required to ensure coordinated seed development.Cell communication within plant seeds has drawn much attention in recent years.In this study,we review current knowledge of cross-talk among the endosperm,embryo,and seed coat during seed development,and highlight recent advances in this field. 展开更多
关键词 cell-cell communication EMBRYO ENDOSPERM seed coat
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Cell-cell communication analysis for single-cell RNA sequencing and its applications in carcinogenesis and COVID-19
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作者 Md Wahiduzzaman Yuexing Liu +2 位作者 Tao Huang Wu Wei Yixue Li 《Biosafety and Health》 CSCD 2022年第4期220-227,共8页
Cell-cell communication is the basis of physiological processes and cell signals.The disease occurs when the cells do not adequately communicate and the messages are blocked.With ligand-receptor interaction databases ... Cell-cell communication is the basis of physiological processes and cell signals.The disease occurs when the cells do not adequately communicate and the messages are blocked.With ligand-receptor interaction databases and single-cell RNA sequencing(scRNA-seq)databases,we can detect intercellular signaling and reconstruct the cell-cell communications among different cell types.This review summarized the computational approaches for analyzing the cell-cell communication based on scRNA-seq data and discussed its applications in carcinogenesis and COVID-19.We believe that this review will accelerate the scRNA-seq data deciphering and facilitate the cell-cell communication studies for complex physiological processes,such as carcinogenesis and SARS-CoV-2 infection. 展开更多
关键词 cell-cell communication Ligand-receptor pair Single-cell RNA sequencing CARCINOGENESIS COVID-19
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Single Photon Detection Technology in Underwater Wireless Optical Communication:Modulation Modes and Error Correction Coding Analysis
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作者 GAI Lei LI Wendong WANG Guoyu 《Journal of Ocean University of China》 CAS CSCD 2024年第2期405-414,共10页
This study explores the application of single photon detection(SPD)technology in underwater wireless optical communication(UWOC)and analyzes the influence of different modulation modes and error correction coding type... This study explores the application of single photon detection(SPD)technology in underwater wireless optical communication(UWOC)and analyzes the influence of different modulation modes and error correction coding types on communication performance.The study investigates the impact of on-off keying(OOK)and 2-pulse-position modulation(2-PPM)on the bit error rate(BER)in single-channel intensity and polarization multiplexing.Furthermore,it compares the error correction performance of low-density parity check(LDPC)and Reed-Solomon(RS)codes across different error correction coding types.The effects of unscattered photon ratio and depolarization ratio on BER are also verified.Finally,a UWOC system based on SPD is constructed,achieving 14.58 Mbps with polarization OOK multiplexing modulation and 4.37 Mbps with polarization 2-PPM multiplexing modulation using LDPC code error correction. 展开更多
关键词 error correction coding modulation mode single photon detection underwater communication wireless optical communication
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Call for Papers--Feature Topic Vol. 22, No. 3, 2025 Special Issue of China Communications: Convergence of 6G empowered Edge Intelligence and Generative AI: Theories, Algorithms, and Applications
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《China Communications》 SCIE CSCD 2024年第4期I0002-I0002,共1页
Generative artificial intelligence(AI), as an emerging paradigm in content generation, has demonstrated its great potentials in creating high-fidelity data including images, texts, and videos. Nowadays wireless networ... Generative artificial intelligence(AI), as an emerging paradigm in content generation, has demonstrated its great potentials in creating high-fidelity data including images, texts, and videos. Nowadays wireless networks and applications have been rapidly evolving from achieving “connected things” to embracing “connected intelligence”. 展开更多
关键词 communicationS wireless networks
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Multi-wavelength nanowire micro-LEDs for future high speed optical communication
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作者 Ayush Pandey Zetian Mi 《Opto-Electronic Advances》 SCIE EI CAS CSCD 2024年第3期1-3,共3页
The future of optoelectronics is directed towards small-area light sources,foremost being microLEDs.However,their use has been inhibited so far primarily due to fabrication and integration challenges,which impair effi... The future of optoelectronics is directed towards small-area light sources,foremost being microLEDs.However,their use has been inhibited so far primarily due to fabrication and integration challenges,which impair efficiency and yield.Recently,bottom-up nanostructures grown using selective area epitaxy have garnered attention as a solution to the aforementioned issues.Prof.Lan Fu et.al.have used this technique to demonstrate uniform p-i-n core-shell InGaAs/InP nanowire array light emitting diodes.The devices are capable of voltage and geometry-controlled multi-wavelength and high-speed operations.Their publication accentuates the wide capabilities of bottom-up nanostructures to resolve the difficulties of nanoscale optoelectronics. 展开更多
关键词 communication high operations
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Optimization of Cooperative RelayingMolecular Communications for Nanomedical Applications
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作者 Eman S.Attia Ashraf A.M.Khalaf +4 位作者 Fathi E.Abd El-Samie Saied M.Abd El-atty Konstantinos A.Lizos Osama Alfarraj Heba M.El-Hoseny 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第2期1259-1275,共17页
Recently,nano-systems based on molecular communications via diffusion(MCvD)have been implemented in a variety of nanomedical applications,most notably in targeted drug delivery system(TDDS)scenarios.Furthermore,becaus... Recently,nano-systems based on molecular communications via diffusion(MCvD)have been implemented in a variety of nanomedical applications,most notably in targeted drug delivery system(TDDS)scenarios.Furthermore,because the MCvD is unreliable and there exists molecular noise and inter symbol interference(ISI),cooperative nano-relays can acquire the reliability for drug delivery to targeted diseased cells,especially if the separation distance between the nano transmitter and nano receiver is increased.In this work,we propose an approach for optimizing the performance of the nano system using cooperative molecular communications with a nano relay scheme,while accounting for blood flow effects in terms of drift velocity.The fractions of the molecular drug that should be allocated to the nano transmitter and nano relay positioning are computed using a collaborative optimization problem solved by theModified Central Force Optimization(MCFO)algorithm.Unlike the previous work,the probability of bit error is expressed in a closed-form expression.It is used as an objective function to determine the optimal velocity of the drug molecules and the detection threshold at the nano receiver.The simulation results show that the probability of bit error can be dramatically reduced by optimizing the drift velocity,detection threshold,location of the nano-relay in the proposed nano system,and molecular drug budget. 展开更多
关键词 Nanomedical system molecular communication cooperative relay OPTIMIZATION
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Cooperative Covert Communication in Multi-Antenna Broadcast Channels
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作者 Qiao Sen Liu Guangjie +1 位作者 Ji Xiaopeng Liu Weiwei 《China Communications》 SCIE CSCD 2024年第6期246-260,共15页
With the gradual popularization of 5G communications,the application of multi-antenna broadcasting technology has become widespread.Therefore,this study aims to investigate the wireless covert communication in the two... With the gradual popularization of 5G communications,the application of multi-antenna broadcasting technology has become widespread.Therefore,this study aims to investigate the wireless covert communication in the two-user cooperative multi-antenna broadcast channel.We focus on the issue that the deteriorated reliability and undetectability are mainly affected by the transmission power.To tackle this issue,we design a scheme based on beamforming to increase the reliability and undetectability of wireless covert communication in the multi-antenna broadcast channel.We first modeled and analyzed the cooperative multi-antenna broadcasting system,and put forward the target question.Then we use the SCA(successive convex approximation)algorithm to transform the target problem into a series of convex subproblems.Then the convex problems are solved and the covert channel capacity is calculated.In order to verify the effectiveness of the scheme,we conducted simulation verification.The simulation results show that the proposed beamforming scheme can effectively improve the reliability and undetectability of covert communication in multi-antenna broadcast channels. 展开更多
关键词 BEAMFORMING covert communication multi-antenna broadcast channels OFDM
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Mutual Information Maximization via Joint Power Allocation in Integrated Sensing and Communications System
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作者 Jia Zhu Junsheng Mu +1 位作者 Yuanhao Cui Xiaojun Jing 《China Communications》 SCIE CSCD 2024年第2期129-142,共14页
In this paper, we focus on the power allocation of Integrated Sensing and Communication(ISAC) with orthogonal frequency division multiplexing(OFDM) waveform. In order to improve the spectrum utilization efficiency in ... In this paper, we focus on the power allocation of Integrated Sensing and Communication(ISAC) with orthogonal frequency division multiplexing(OFDM) waveform. In order to improve the spectrum utilization efficiency in ISAC, we propose a design scheme based on spectrum sharing, that is,to maximize the mutual information(MI) of radar sensing while ensuring certain communication rate and transmission power constraints. In the proposed scheme, three cases are considered for the scattering off the target due to the communication signals,as negligible signal, beneficial signal, and interference signal to radar sensing, respectively, thus requiring three power allocation schemes. However,the corresponding power allocation schemes are nonconvex and their closed-form solutions are unavailable as a consequence. Motivated by this, alternating optimization(AO), sequence convex programming(SCP) and Lagrange multiplier are individually combined for three suboptimal solutions corresponding with three power allocation schemes. By combining the three algorithms, we transform the non-convex problem which is difficult to deal with into a convex problem which is easy to solve and obtain the suboptimal solution of the corresponding optimization problem. Numerical results show that, compared with the allocation results of the existing algorithms, the proposed joint design algorithm significantly improves the radar performance. 展开更多
关键词 COEXISTENCE communicationS multicarrier radar mutual information spectrum sharing
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Energy-Efficient Implementation of BCD to Excess-3 Code Converter for Nano-Communication Using QCA Technology
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作者 Nuriddin Safoev Angshuman Khan +1 位作者 Khudoykulov Zarif Turakulovich Rajeev Arya 《China Communications》 SCIE CSCD 2024年第6期103-111,共9页
Code converters are essential in digital nano communication;therefore,a low-complexity optimal QCA layout for a BCD to Excess-3 code converter has been proposed in this paper.A QCA clockphase-based design technique wa... Code converters are essential in digital nano communication;therefore,a low-complexity optimal QCA layout for a BCD to Excess-3 code converter has been proposed in this paper.A QCA clockphase-based design technique was adopted to investigate integration with other complicated circuits.Using a unique XOR gate,the recommended circuit’s cell complexity has been decreased.The findings produced using the QCADesigner-2.0.3,a reliable simulation tool,prove the effectiveness of the current structure over earlier designs by considering the number of cells deployed,the area occupied,and the latency as design metrics.In addition,the popular tool QCAPro was used to estimate the energy dissipation of the proposed design.The proposed technique reduces the occupied space by∼40%,improves cell complexity by∼20%,and reduces energy dissipation by∼1.8 times(atγ=1.5EK)compared to the current scalable designs.This paper also studied the suggested structure’s energy dissipation and compared it to existing works for a better performance evaluation. 展开更多
关键词 BCD code converter Excess-3 nano communication QCA circuits
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Falcon Optimization Algorithm-Based Energy Efficient Communication Protocol for Cluster-Based Vehicular Networks
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作者 Youseef Alotaibi B.Rajasekar +1 位作者 R.Jayalakshmi Surendran Rajendran 《Computers, Materials & Continua》 SCIE EI 2024年第3期4243-4262,共20页
Rapid development in Information Technology(IT)has allowed several novel application regions like large outdoor vehicular networks for Vehicle-to-Vehicle(V2V)transmission.Vehicular networks give a safe and more effect... Rapid development in Information Technology(IT)has allowed several novel application regions like large outdoor vehicular networks for Vehicle-to-Vehicle(V2V)transmission.Vehicular networks give a safe and more effective driving experience by presenting time-sensitive and location-aware data.The communication occurs directly between V2V and Base Station(BS)units such as the Road Side Unit(RSU),named as a Vehicle to Infrastructure(V2I).However,the frequent topology alterations in VANETs generate several problems with data transmission as the vehicle velocity differs with time.Therefore,the scheme of an effectual routing protocol for reliable and stable communications is significant.Current research demonstrates that clustering is an intelligent method for effectual routing in a mobile environment.Therefore,this article presents a Falcon Optimization Algorithm-based Energy Efficient Communication Protocol for Cluster-based Routing(FOA-EECPCR)technique in VANETS.The FOA-EECPCR technique intends to group the vehicles and determine the shortest route in the VANET.To accomplish this,the FOA-EECPCR technique initially clusters the vehicles using FOA with fitness functions comprising energy,distance,and trust level.For the routing process,the Sparrow Search Algorithm(SSA)is derived with a fitness function that encompasses two variables,namely,energy and distance.A series of experiments have been conducted to exhibit the enhanced performance of the FOA-EECPCR method.The experimental outcomes demonstrate the enhanced performance of the FOA-EECPCR approach over other current methods. 展开更多
关键词 Vehicular networks communication protocol CLUSTERING falcon optimization algorithm ROUTING
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Age of Information for Short-Packet Covert Communication with Time Modulated Retrodirective Array
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作者 Ma Yue Ma Ruiqian +4 位作者 Lin Zhi Yang Weiwei Cai Yueming Miao Chen Wu Wen 《China Communications》 SCIE CSCD 2024年第4期23-37,共15页
In this paper,the covert age of information(CAoI),which characterizes the timeliness and covertness performance of communication,is first investigated in the short-packet covert communication with time modulated retro... In this paper,the covert age of information(CAoI),which characterizes the timeliness and covertness performance of communication,is first investigated in the short-packet covert communication with time modulated retrodirective array(TMRDA).Specifically,the TMRDA is designed to maximize the antenna gain in the target direction while the side lobe is sufficiently suppressed.On this basis,the covertness constraint and CAoI are derived in closed form.To facilitate the covert transmission design,the transmit power and block-length are jointly optimized to minimize the CAoI,which demonstrates the trade-off between covertness and timelessness.Our results illustrate that there exists an optimal block-length that yields the minimum CAoI,and the presented optimization results can achieve enhanced performance compared with the fixed block-length case.Additionally,we observe that smaller beam pointing error at Bob leads to improvements in CAoI. 展开更多
关键词 age of information covert communication retrodirective array time modulation
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Mega-Constellations Based TT&C Resource Sharing: Keep Reliable Aeronautical Communication in an Emergency
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作者 Haoran Xie Yafeng Zhan Jianhua Lu 《China Communications》 SCIE CSCD 2024年第2期1-16,共16页
With the development of the transportation industry, the effective guidance of aircraft in an emergency to prevent catastrophic accidents remains one of the top safety concerns. Undoubtedly, operational status data of... With the development of the transportation industry, the effective guidance of aircraft in an emergency to prevent catastrophic accidents remains one of the top safety concerns. Undoubtedly, operational status data of the aircraft play an important role in the judgment and command of the Operational Control Center(OCC). However, how to transmit various operational status data from abnormal aircraft back to the OCC in an emergency is still an open problem. In this paper, we propose a novel Telemetry, Tracking,and Command(TT&C) architecture named Collaborative TT&C(CoTT&C) based on mega-constellation to solve such a problem. CoTT&C allows each satellite to help the abnormal aircraft by sharing TT&C resources when needed, realizing real-time and reliable aeronautical communication in an emergency. Specifically, we design a dynamic resource sharing mechanism for CoTT&C and model the mechanism as a single-leader-multi-follower Stackelberg game. Further, we give an unique Nash Equilibrium(NE) of the game as a closed form. Simulation results demonstrate that the proposed resource sharing mechanism is effective, incentive compatible, fair, and reciprocal. We hope that our findings can shed some light for future research on aeronautical communications in an emergency. 展开更多
关键词 aeronautical emergency communication mega-constellation networked TT&C resource allocation stackelberg game
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Cooperative User-Scheduling and Resource Allocation Optimization for Intelligent Reflecting Surface Enhanced LEO Satellite Communication
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作者 Meng Meng Bo Hu +1 位作者 Shanzhi Chen Jianyin Zhang 《China Communications》 SCIE CSCD 2024年第2期227-244,共18页
Lower Earth Orbit(LEO) satellite becomes an important part of complementing terrestrial communication due to its lower orbital altitude and smaller propagation delay than Geostationary satellite. However, the LEO sate... Lower Earth Orbit(LEO) satellite becomes an important part of complementing terrestrial communication due to its lower orbital altitude and smaller propagation delay than Geostationary satellite. However, the LEO satellite communication system cannot meet the requirements of users when the satellite-terrestrial link is blocked by obstacles. To solve this problem, we introduce Intelligent reflect surface(IRS) for improving the achievable rate of terrestrial users in LEO satellite communication. We investigated joint IRS scheduling, user scheduling, power and bandwidth allocation(JIRPB) optimization algorithm for improving LEO satellite system throughput.The optimization problem of joint user scheduling and resource allocation is formulated as a non-convex optimization problem. To cope with this problem, the nonconvex optimization problem is divided into resource allocation optimization sub-problem and scheduling optimization sub-problem firstly. Second, we optimize the resource allocation sub-problem via alternating direction multiplier method(ADMM) and scheduling sub-problem via Lagrangian dual method repeatedly.Third, we prove that the proposed resource allocation algorithm based ADMM approaches sublinear convergence theoretically. Finally, we demonstrate that the proposed JIRPB optimization algorithm improves the LEO satellite communication system throughput. 展开更多
关键词 convex optimization intelligent reflecting surface LEO satellite communication OFDM
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