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Short Baseline Positioning with an Improved Time Reversal Technique in a Multi-path Channel 被引量:2
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作者 Zhuang Li Gang Qiao Zongxin Sun Haiyang Zhao Ran Guo 《Journal of Marine Science and Application》 2012年第2期251-257,共7页
The existence of a multi-path channel under the water greatly decreases the accuracy of the short baseline positioning system.In this paper,the application of a time reversal mirror to the short baseline positioning s... The existence of a multi-path channel under the water greatly decreases the accuracy of the short baseline positioning system.In this paper,the application of a time reversal mirror to the short baseline positioning system was investigated.The time reversal mirror technique allowed the acoustic signal to better focus in an unknown environment,which effectively reduced the expansion of multi-path acoustic signals as well as improved the signal focusing.The signal-to-noise ratio(SNR) of the time reversal operator greatly increased and could be obtained by ensonifying the water.The technique was less affected by the environment and therefore more applicable to a complex shallow water environment.Numerical simulations and pool experiments were used to demonstrate the efficiency of this technique. 展开更多
关键词 short baseline positioning focusing gain time reversal mirror multi-path channel ocean acoustic channel acoustic signal processing
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Multi-access performance of DS UWB systemunder indoor dense multi-path channel
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作者 樊祥宁 倪剑强 毕光国 《Journal of Southeast University(English Edition)》 EI CAS 2005年第4期393-397,共5页
The performance of multi-user code to direct spreading bi-phase shift keying (DS-BPSK) direct impulse ultra wideband (UWB) systems under indoor multi-user and multi-path environment is analyzed and simulated. The ... The performance of multi-user code to direct spreading bi-phase shift keying (DS-BPSK) direct impulse ultra wideband (UWB) systems under indoor multi-user and multi-path environment is analyzed and simulated. The system output signals with Rake receiver are derived, then a simple and practical code selection scheme is given; i. e., with a large occupation to empty ratio of the repeating pulses, directly choosing those random or pseudo-random user codes with enough length and good co-relative orthogonal features will make the performance of DS-BPSK approximate the optimum and, so there is no need to carefully design the code or its type. The system multi-access performances are simulated using Gold sequence and PN codes as multi-user codes under CMI-CM4 multi-path channels. Simulation results prove that the proposed scheme is feasible. 展开更多
关键词 ultra wideband multi-access multi-path Gold code direct sequence RAKE
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Voltage-dependent anion channel 1 oligomerization regulates PANoptosis in retinal ischemia–reperfusion injury 被引量:1
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作者 Hao Wan Xiaoxia Ban +6 位作者 Ye He Yandi Yang Ximin Hu Lei Shang Xinxing Wan Qi Zhang Kun Xiong 《Neural Regeneration Research》 2026年第4期1652-1664,共13页
Ischemia–reperfusion injury is a common pathophysiological mechanism in retinal degeneration.PANoptosis is a newly defined integral form of regulated cell death that combines the key features of pyroptosis,apoptosis,... Ischemia–reperfusion injury is a common pathophysiological mechanism in retinal degeneration.PANoptosis is a newly defined integral form of regulated cell death that combines the key features of pyroptosis,apoptosis,and necroptosis.Oligomerization of mitochondrial voltage-dependent anion channel 1 is an important pathological event in regulating cell death in retinal ischemia–reperfusion injury.However,its role in PANoptosis remains largely unknown.In this study,we demonstrated that voltage-dependent anion channel 1 oligomerization-mediated mitochondrial dysfunction was associated with PANoptosis in retinal ischemia–reperfusion injury.Inhibition of voltage-dependent anion channel 1 oligomerization suppressed mitochondrial dysfunction and PANoptosis in retinal cells subjected to ischemia–reperfusion injury.Mechanistically,mitochondria-derived reactive oxygen species played a central role in the voltagedependent anion channel 1-mediated regulation of PANoptosis by promoting PANoptosome assembly.Moreover,inhibiting voltage-dependent anion channel 1 oligomerization protected against PANoptosis in the retinas of rats subjected to ischemia–reperfusion injury.Overall,our findings reveal the critical role of voltage-dependent anion channel 1 oligomerization in regulating PANoptosis in retinal ischemia–reperfusion injury,highlighting voltage-dependent anion channel 1 as a promising therapeutic target. 展开更多
关键词 1-methyl-4-phenyl-1 2 3 6-TETRAHYDROPYRIDINE apoptosis ischemia–reperfusion injury mitochondrial dysfunction NECROPTOSIS oxidative stress PANoptosis PYROPTOSIS reactive oxygen species voltage-dependent anion channel 1
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Neuronal ion channel modulation by Drimys winteri compounds:Opening a new chemical space to neuropharmacology
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作者 Macarena EMeza Oscar Ramirez-Molina +4 位作者 Oscar Flores Katherine Farina-Oliva Pamela A.Godoy Jorge Fuentealba Gonzalo E.Yevenes 《Neural Regeneration Research》 2026年第4期1373-1382,共10页
Numerous pathological states of the nervous system involve alterations in neuronal excitability and synaptic dysfunction,which depend on the function of ion channels.Due to their critical involvement in health and dis... Numerous pathological states of the nervous system involve alterations in neuronal excitability and synaptic dysfunction,which depend on the function of ion channels.Due to their critical involvement in health and disease,the search for new compounds that modulate these proteins is still relevant.Traditional medicine has long been a rich source of neuroactive compounds.For example,the indigenous Mapuche people have used the leaves and bark of the Drimys winteri tree for centuries to treat various diseases.Consequently,several studies have investigated the biological effects of compounds in Drimys winteri,highlighting sesquiterpenes such asα-humulene,drimenin,polygodial,andα-,β-,γ-eudesmol.However,there is currently no literature review focusing on the ability of these sesquiterpenes to modulate ion channels.This review summarizes the current knowledge about neuroactive compounds found in Drimys winteri,with special emphasis on their direct actions on neuronal ion channels.Several Drimys winteri sesquiterpenes modulate a diverse array of neuronal ion channels,including transient receptor potential channels,gamma-aminobutyric acid A receptors,nicotinic acetylcholine receptors,and voltage-dependent Ca^(2+)and Na^(+)channels.Interestingly,the modulation of these molecular targets by Drimys winteri sesquiterpenes correlates with their therapeutic actions.The promiscuous pharmacological profile of Drimys winteri sesquiterpenes suggests they modulate multiple protein targets in vivo,making them potentially useful for treating complex,multifactorial diseases.Further studies at the molecular level may aid in developing multitargeted drugs with enhanced therapeutic effects. 展开更多
关键词 drimenin Drimys winteri gamma-aminobutyric acid A receptors ion channels nicotinic acetylcholine receptors polygodial SESQUITERPENES transient receptor potential voltage-gated calcium channels voltage-gated sodium channels α- β- γ-eudesmol α-humulene
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LNN Blind Multi-user Detection Algorithm for Multi-path-fading CDMA Channels
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作者 李艳萍 王华奎 苗瑞清 《Defence Technology(防务技术)》 SCIE EI CAS 2006年第3期214-218,共5页
关键词 CDMA BMUD 实时追踪 LNN 通信 错误诊断
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Emulation of Realistic Multi-Path Propagation Channels inside an Anechoic Chamber for Antenna Diversity Measurements
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作者 Alaa Choumane Ahmad El Sayed Ahmad Khaled Khoder 《Wireless Engineering and Technology》 2020年第1期1-12,共12页
As antennas are inherently included recommended in Over-The-Air (OTA) testing, it is important to also consider realistic channel models for the multiple-input multiple-output (MIMO) device performance evaluation. Thi... As antennas are inherently included recommended in Over-The-Air (OTA) testing, it is important to also consider realistic channel models for the multiple-input multiple-output (MIMO) device performance evaluation. This paper aims to emulate realistic multi-Path propagation channels in terms of angles of arrivals (AoA) and cross-polarization ratio (XPR) with Rayleigh fading, inside an anechoic chamber, for antenna diversity measurements. In this purpose, a practical multi-probe anechoic chamber measurement system (MPAC) with 24 probe antennas (SATIMO SG24) has been used. However, the actual configuration of this system is not able to reproduce realistic channels. Therefore, a new method based on the control of the SG24 probes has been developed. At first time, this method has been validated numerically through the comparison of simulated and analytical AoA probability density distributions. At the second time, the performance of an antenna diversity system inside the SG24 has been performed in terms of the correlation coefficient and diversity gain (DG) using an antenna reference system. Simulated and measurements results have shown a good agreement. 展开更多
关键词 channel Emulation multi-path OTA Measurements Antenna Diversity Measurements MIMO Correlation Coefficient Diversity Gain
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ChannelLink:基于链下状态通道的跨片状态迁移协议 被引量:1
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作者 贾林鹏 孙毅 《软件学报》 北大核心 2025年第3期1327-1354,共28页
跨片状态迁移协议是保证跨片交易处理原子性的基础,其效率高低将直接影响分片系统性能.现有协议处理过程可以分为源分片状态迁出、片间状态传输和目的分片状态迁入这3个阶段,各阶段依次执行、紧密绑定.利用链下状态通道灵活度高、即时... 跨片状态迁移协议是保证跨片交易处理原子性的基础,其效率高低将直接影响分片系统性能.现有协议处理过程可以分为源分片状态迁出、片间状态传输和目的分片状态迁入这3个阶段,各阶段依次执行、紧密绑定.利用链下状态通道灵活度高、即时确认的特点,提出了ChannelLink跨片状态迁移协议,将现有协议中紧密耦合的三阶段处理过程解耦,有效降低了跨片交易平均开销,提升了状态迁移效率.基于此,设计了一种低开销链下通道路由算法.该算法基于状态迁移交易与链下通道拓扑等特征,通过改进遗传算法,求解最优状态路由方案,兼顾迁移效率的同时,降低了用户跨片状态迁移开销.最后,实现了ChannelLink协议原型系统,并基于比特币交易以及闪电网络状态信息构造数据集进行实验验证.实验结果表明,该协议在16个分片、跨片交易比例为5.21%的场景下,分片系统吞吐量提升7.04%,交易确认延迟降低52.51%,跨片状态迁移开销下降45.44%以上,并且随着分片数量与跨片交易比例的上升,该协议的性能优势逐步扩大. 展开更多
关键词 区块链 分片 状态迁移 状态通道 路由算法
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Separate Source Channel Coding Is Still What You Need:An LLM-Based Rethinking 被引量:3
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作者 REN Tianqi LI Rongpeng +5 位作者 ZHAO Mingmin CHEN Xianfu LIU Guangyi YANG Yang ZHAO Zhifeng ZHANG Honggang 《ZTE Communications》 2025年第1期30-44,共15页
Along with the proliferating research interest in semantic communication(Sem Com),joint source channel coding(JSCC)has dominated the attention due to the widely assumed existence in efficiently delivering information ... Along with the proliferating research interest in semantic communication(Sem Com),joint source channel coding(JSCC)has dominated the attention due to the widely assumed existence in efficiently delivering information semantics.Nevertheless,this paper challenges the conventional JSCC paradigm and advocates for adopting separate source channel coding(SSCC)to enjoy a more underlying degree of freedom for optimization.We demonstrate that SSCC,after leveraging the strengths of the Large Language Model(LLM)for source coding and Error Correction Code Transformer(ECCT)complemented for channel coding,offers superior performance over JSCC.Our proposed framework also effectively highlights the compatibility challenges between Sem Com approaches and digital communication systems,particularly concerning the resource costs associated with the transmission of high-precision floating point numbers.Through comprehensive evaluations,we establish that assisted by LLM-based compression and ECCT-enhanced error correction,SSCC remains a viable and effective solution for modern communication systems.In other words,separate source channel coding is still what we need. 展开更多
关键词 separate source channel coding(SSCC) joint source channel coding(JSCC) end-to-end communication system Large Language Model(LLM) lossless text compression Error Correction Code Transformer(ECCT)
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Potassium and calcium channels in different nerve cells act as therapeutic targets in neurological disorders
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作者 Qing Qiu Mengting Yang +2 位作者 Danfeng Gong Haiying Liang Tingting Chen 《Neural Regeneration Research》 SCIE CAS 2025年第5期1258-1276,共19页
The central nervous system, information integration center of the body, is mainly composed of neurons and glial cells. The neuron is one of the most basic and important structural and functional units of the central n... The central nervous system, information integration center of the body, is mainly composed of neurons and glial cells. The neuron is one of the most basic and important structural and functional units of the central nervous system, with sensory stimulation and excitation conduction functions. Astrocytes and microglia belong to the glial cell family, which is the main source of cytokines and represents the main defense system of the central nervous system. Nerve cells undergo neurotransmission or gliotransmission, which regulates neuronal activity via the ion channels, receptors, or transporters expressed on nerve cell membranes. Ion channels, composed of large transmembrane proteins, play crucial roles in maintaining nerve cell homeostasis. These channels are also important for control of the membrane potential and in the secretion of neurotransmitters. A variety of cellular functions and life activities, including functional regulation of the central nervous system, the generation and conduction of nerve excitation, the occurrence of receptor potential, heart pulsation, smooth muscle peristalsis, skeletal muscle contraction, and hormone secretion, are closely related to ion channels associated with passive transmembrane transport. Two types of ion channels in the central nervous system, potassium channels and calcium channels, are closely related to various neurological disorders, including Alzheimer's disease, Parkinson's disease, and epilepsy. Accordingly, various drugs that can affect these ion channels have been explored deeply to provide new directions for the treatment of these neurological disorders. In this review, we focus on the functions of potassium and calcium ion channels in different nerve cells and their involvement in neurological disorders such as Parkinson's disease, Alzheimer's disease, depression, epilepsy, autism, and rare disorders. We also describe several clinical drugs that target potassium or calcium channels in nerve cells and could be used to treat these disorders. We concluded that there are few clinical drugs that can improve the pathology these diseases by acting on potassium or calcium ions. Although a few novel ion-channelspecific modulators have been discovered, meaningful therapies have largely not yet been realized. The lack of target-specific drugs, their requirement to cross the blood–brain barrier, and their exact underlying mechanisms all need further attention. This review aims to explain the urgent problems that need research progress and provide comprehensive information aiming to arouse the research community's interest in the development of ion channel-targeting drugs and the identification of new therapeutic targets for that can increase the cure rate of nervous system diseases and reduce the occurrence of adverse reactions in other systems. 展开更多
关键词 ASTROCYTES calcium channels central nervous system extracellular ion concentration MICROGLIA neurological disorders NEURONS potassium channels
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Development and evaluation of organic/metal ion double crosslinking polymer gel for anti-CO_(2)gas channeling in high temperature and low permeability reservoirs 被引量:2
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作者 Hong-Bin Yang Hai-Zhuang Jiang +7 位作者 Zhe Xu Xing Zhang Tao Wang Hai-Ning Liu Xiao Ma Jian-Jun Zhu Xiang-Feng Zhang Wan-Li Kang 《Petroleum Science》 2025年第2期724-738,共15页
CO_(2)flooding enhanced oil recovery(CO_(2)-EOR)represents a significant technology in the low permeability reservoir.With the fractures and heterogeneity in low permeability reservoirs,CO_(2)-EOR is susceptible to pe... CO_(2)flooding enhanced oil recovery(CO_(2)-EOR)represents a significant technology in the low permeability reservoir.With the fractures and heterogeneity in low permeability reservoirs,CO_(2)-EOR is susceptible to pessimistic gas channeling.Consequently,there is a need to develop conformance control materials that can be used in CO_(2)-EOR.Herein,to address the challenges of low strength and poor stability of polymer gel in high temperature and low permeability reservoirs,a new organic/metal ion composite crosslinking polymer gel(AR-Gel)is reported,which is formed by low hydrolysis and medium to high molecular weight polymer(CX-305),organic crosslinking agent(phenolic resin),and aluminium citrate(AI(Ⅲ)).The crosslinking of AI(Ⅲ)with carboxyl group and organic/metal ion double crosslinking can construct a more complex and stable polymer gel structure on the basis of traditional chemical crosslinking,to cope with the harsh conditions such as high temperature.The structure-activity relationship of AR-Gel was revealed by rheology behavior and micro-morphology.The applicability of AR-Gel in reservoir was investigated,as was its strength and stability in supercritical CO_(2).The anti-gas channeling and enhanced oil recovery of AR-Gel were investigated using low permeability fractured cores,and the field process parameters were provided.The gel can be used to meet supercritical CO_(2)reservoirs at 110℃and 20,000 mg/L salinity,with long-term stability over 60 days.The plugging rate of AR-Gel for fractured co re was 97%,with subsequent CO_(2)flooding re sulting in an enhanced oil recovery by 34.5%.ARGel can effectively control CO_(2)gas channeling and enhanced oil recovery.It offers a new material with high strength and temperature resistance,which is particularly beneficial in the CO_(2)flooding for the conformance control of oil field. 展开更多
关键词 High temperature and low permeability reservoir CO_(2)flooding Anti-gas channeling Polymer gel
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GPT2-ICC:A data-driven approach for accurate ion channel identification using pre-trained large language models 被引量:1
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作者 Zihan Zhou Yang Yu +9 位作者 Chengji Yang Leyan Cao Shaoying Zhang Junnan Li Yingnan Zhang Huayun Han Guoliang Shi Qiansen Zhang Juwen Shen Huaiyu Yang 《Journal of Pharmaceutical Analysis》 2025年第8期1800-1809,共10页
Current experimental and computational methods have limitations in accurately and efficiently classifying ion channels within vast protein spaces.Here we have developed a deep learning algorithm,GPT2 Ion Channel Class... Current experimental and computational methods have limitations in accurately and efficiently classifying ion channels within vast protein spaces.Here we have developed a deep learning algorithm,GPT2 Ion Channel Classifier(GPT2-ICC),which effectively distinguishing ion channels from a test set containing approximately 239 times more non-ion-channel proteins.GPT2-ICC integrates representation learning with a large language model(LLM)-based classifier,enabling highly accurate identification of potential ion channels.Several potential ion channels were predicated from the unannotated human proteome,further demonstrating GPT2-ICC’s generalization ability.This study marks a significant advancement in artificial-intelligence-driven ion channel research,highlighting the adaptability and effectiveness of combining representation learning with LLMs to address the challenges of imbalanced protein sequence data.Moreover,it provides a valuable computational tool for uncovering previously uncharacterized ion channels. 展开更多
关键词 Ion channel Artificial intelligence Representation learning GPT2 Protein language model
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Irreversibility analysis and multiple cubic regression based efficiency evaluation of ternary nanofluids(TiO_(2)+SiO_(2)+Al_(2)O_(3)/H_(2)O and TiO_(2)+SiO_(2)+Cu/H_(2)O)via converging/diverging channels 被引量:1
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作者 Siddhant Taneja Sapna Sharma Bhuvaneshvar Kumar 《Acta Mechanica Sinica》 2025年第6期63-75,共13页
This study numerically examines the heat and mass transfer characteristics of two ternary nanofluids via converging and diverg-ing channels.Furthermore,the study aims to assess two ternary nanofluids combinations to d... This study numerically examines the heat and mass transfer characteristics of two ternary nanofluids via converging and diverg-ing channels.Furthermore,the study aims to assess two ternary nanofluids combinations to determine which configuration can provide better heat and mass transfer and lower entropy production,while ensuring cost efficiency.This work bridges the gap be-tween academic research and industrial feasibility by incorporating cost analysis,entropy generation,and thermal efficiency.To compare the velocity,temperature,and concentration profiles,we examine two ternary nanofluids,i.e.,TiO_(2)+SiO_(2)+Al_(2)O_(3)/H_(2)O and TiO_(2)+SiO_(2)+Cu/H_(2)O,while considering the shape of nanoparticles.The velocity slip and Soret/Dufour effects are taken into consideration.Furthermore,regression analysis for Nusselt and Sherwood numbers of the model is carried out.The Runge-Kutta fourth-order method with shooting technique is employed to acquire the numerical solution of the governed system of ordinary differential equations.The flow pattern attributes of ternary nanofluids are meticulously examined and simulated with the fluc-tuation of flow-dominating parameters.Additionally,the influence of these parameters is demonstrated in the flow,temperature,and concentration fields.For variation in Eckert and Dufour numbers,TiO_(2)+SiO_(2)+Al_(2)O_(3)/H_(2)O has a higher temperature than TiO_(2)+SiO_(2)+Cu/H_(2)O.The results obtained indicate that the ternary nanofluid TiO_(2)+SiO_(2)+Al_(2)O_(3)/H_(2)O has a higher heat transfer rate,lesser entropy generation,greater mass transfer rate,and lower cost than that of TiO_(2)+SiO_(2)+Cu/H_(2)O ternary nanofluid. 展开更多
关键词 Converging/Diverging channels Ternary nanofluids Multiple cubic regression Entropy generation
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Engine Misfire Fault Detection Based on the Channel Attention Convolutional Model
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作者 Feifei Yu Yongxian Huang +3 位作者 Guoyan Chen Xiaoqing Yang Canyi Du Yongkang Gong 《Computers, Materials & Continua》 SCIE EI 2025年第1期843-862,共20页
To accurately diagnosemisfire faults in automotive engines,we propose a Channel Attention Convolutional Model,specifically the Squeeze-and-Excitation Networks(SENET),for classifying engine vibration signals and precis... To accurately diagnosemisfire faults in automotive engines,we propose a Channel Attention Convolutional Model,specifically the Squeeze-and-Excitation Networks(SENET),for classifying engine vibration signals and precisely pinpointing misfire faults.In the experiment,we established a total of 11 distinct states,encompassing the engine’s normal state,single-cylinder misfire faults,and dual-cylinder misfire faults for different cylinders.Data collection was facilitated by a highly sensitive acceleration signal collector with a high sampling rate of 20,840Hz.The collected data were methodically divided into training and testing sets based on different experimental groups to ensure generalization and prevent overlap between the two sets.The results revealed that,with a vibration acceleration sequence of 1000 time steps(approximately 50 ms)as input,the SENET model achieved a misfire fault detection accuracy of 99.8%.For comparison,we also trained and tested several commonly used models,including Long Short-Term Memory(LSTM),Transformer,and Multi-Scale Residual Networks(MSRESNET),yielding accuracy rates of 84%,79%,and 95%,respectively.This underscores the superior accuracy of the SENET model in detecting engine misfire faults compared to other models.Furthermore,the F1 scores for each type of recognition in the SENET model surpassed 0.98,outperforming the baseline models.Our analysis indicated that the misclassified samples in the LSTM and Transformer models’predictions were primarily due to intra-class misidentifications between single-cylinder and dual-cylinder misfire scenarios.To delve deeper,we conducted a visual analysis of the features extracted by the LSTM and SENET models using T-distributed Stochastic Neighbor Embedding(T-SNE)technology.The findings revealed that,in the LSTMmodel,data points of the same type tended to cluster together with significant overlap.Conversely,in the SENET model,data points of various types were more widely and evenly dispersed,demonstrating its effectiveness in distinguishing between different fault types. 展开更多
关键词 channel attention SENET model engine misfire fault fault detection
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Flow and heat transfer characteristics of regenerative cooling parallel channel
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作者 JU Yinchao LIU Xiaoyong +1 位作者 XU Guoqiang DONG Bensi 《推进技术》 北大核心 2025年第1期163-171,共9页
Due to the complex high-temperature characteristics of hydrocarbon fuel,the research on the long-term working process of parallel channel structure under variable working conditions,especially under high heat-mass rat... Due to the complex high-temperature characteristics of hydrocarbon fuel,the research on the long-term working process of parallel channel structure under variable working conditions,especially under high heat-mass ratio,has not been systematically carried out.In this paper,the heat transfer and flow characteristics of related high temperature fuels are studied by using typical engine parallel channel structure.Through numeri⁃cal simulation and systematic experimental verification,the flow and heat transfer characteristics of parallel chan⁃nels under typical working conditions are obtained,and the effectiveness of high-precision calculation method is preliminarily established.It is known that the stable time required for hot start of regenerative cooling engine is about 50 s,and the flow resistance of parallel channel structure first increases and then decreases with the in⁃crease of equivalence ratio(The following equivalence ratio is expressed byΦ),and there is a flow resistance peak in the range ofΦ=0.5~0.8.This is mainly caused by the coupling effect of high temperature physical proper⁃ties,flow rate and pressure of fuel in parallel channels.At the same time,the cooling and heat transfer character⁃istics of parallel channels under some conditions of high heat-mass ratio are obtained,and the main factors affect⁃ing the heat transfer of parallel channels such as improving surface roughness and strengthening heat transfer are mastered.In the experiment,whenΦis less than 0.9,the phenomenon of local heat transfer enhancement and deterioration can be obviously observed,and the temperature rise of local structures exceeds 200℃,which is the risk of structural damage.Therefore,the reliability of long-term parallel channel structure under the condition of high heat-mass ratio should be fully considered in structural design. 展开更多
关键词 Regenerative cooling Heat transfer Flow resistance ENGINE Parallel channel
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An optimal design of the liquid-cooling plate channel in a power battery based on response surface methodology
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作者 Jinbo Zheng Jibin Jiang +2 位作者 Xiwei Yu Bingjun Yan Guofu Lian 《中国科学技术大学学报》 北大核心 2025年第2期52-65,51,I0002,共16页
The work takes a new liquid-cooling plate in a power battery with pin fins inside the channel as the object.A mathematical model is established via the central composite design of the response surface to study the rel... The work takes a new liquid-cooling plate in a power battery with pin fins inside the channel as the object.A mathematical model is established via the central composite design of the response surface to study the relationships among the length,width,height,and spacing of pin fins;the maximum temperature and temperature difference of the battery module;and the pressure drop of the liquid-cooling plate.Model accuracy is verified via variance analysis.The new liquid-cooling plate enables the power battery to work within an optimal temperature range.Appropriately increasing the length,width,and height and reducing the spacing of pin fins could reduce the temperature of the power battery module and improve the temperature uniformity.However,the pressure drop of the liquid-cooling plate increases.The structural parameters of the pin fins are optimized to minimize the maximum temperature and the temperature difference of the battery module as well as the pressure drop of the liquid-cooling plate.The errors between the values predicted and actual by the simulation test are 0.58%,4%,and 0.48%,respectively,which further verifies the model accuracy.The results reveal the influence of the structural parameters of the pin fins inside the liquid-cooling plate on its heat dissipation performance and pressure drop characteristics.A theoretical basis is provided for the design of liquid-cooling plates in power batteries and the optimization of structural parameters. 展开更多
关键词 response surface methodology power battery cooling channel optimal design
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Secure Channel Estimation Using Norm Estimation Model for 5G Next Generation Wireless Networks
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作者 Khalil Ullah Song Jian +4 位作者 Muhammad Naeem Ul Hassan Suliman Khan Mohammad Babar Arshad Ahmad Shafiq Ahmad 《Computers, Materials & Continua》 SCIE EI 2025年第1期1151-1169,共19页
The emergence of next generation networks(NextG),including 5G and beyond,is reshaping the technological landscape of cellular and mobile networks.These networks are sufficiently scaled to interconnect billions of user... The emergence of next generation networks(NextG),including 5G and beyond,is reshaping the technological landscape of cellular and mobile networks.These networks are sufficiently scaled to interconnect billions of users and devices.Researchers in academia and industry are focusing on technological advancements to achieve highspeed transmission,cell planning,and latency reduction to facilitate emerging applications such as virtual reality,the metaverse,smart cities,smart health,and autonomous vehicles.NextG continuously improves its network functionality to support these applications.Multiple input multiple output(MIMO)technology offers spectral efficiency,dependability,and overall performance in conjunctionwithNextG.This article proposes a secure channel estimation technique in MIMO topology using a norm-estimation model to provide comprehensive insights into protecting NextG network components against adversarial attacks.The technique aims to create long-lasting and secure NextG networks using this extended approach.The viability of MIMO applications and modern AI-driven methodologies to combat cybersecurity threats are explored in this research.Moreover,the proposed model demonstrates high performance in terms of reliability and accuracy,with a 20%reduction in the MalOut-RealOut-Diff metric compared to existing state-of-the-art techniques. 展开更多
关键词 Next generation networks massive mimo communication network artificial intelligence 5G adversarial attacks channel estimation information security
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Structural insights into the plant mechanosensitive ion channels OSCA2.2 and OSCA3.1
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作者 Yue Guan Yongxiang Gao +1 位作者 Xin Liu Linfeng Sun 《中国科学技术大学学报》 北大核心 2025年第6期2-9,1,I0001,共10页
Mechanosensitive ion channels are essential for sensing and converting mechanical forces into electrical or chemical signals.These channels are widely distributed across bacteria,animals,and plants.In Arabidopsis thal... Mechanosensitive ion channels are essential for sensing and converting mechanical forces into electrical or chemical signals.These channels are widely distributed across bacteria,animals,and plants.In Arabidopsis thaliana,the OSCA family has been identified as mechanically activated ion channels that respond to osmotic stress by allowing calcium ions to enter the cell.This influx increases the cytoplasmic calcium concentration,triggering osmotic stress-induced signal transduction cascades in plants.In this study,we determined the structures of OSCA2.2 and OSCA3.1 via cryoelectron microscopy(cryo-EM).Both proteins form homodimers consisting of 11 transmembrane helices(TM1–11).The ion conduction pathway is formed by TM4–8.Despite belonging to the same family,OSCA2.2 and OSCA3.1 exhibit notable structural variations.Structural analysis revealed that both OSCA2.2 and OSCA3.1 exhibit a closed conformation.We also conducted functional studies on OSCA proteins via electrophysiological experiments and confirmed the role of key amino acids in the process of ion permeation. 展开更多
关键词 calcium ion mechanosensitive ion channel OSCA2.2 OSCA3.1 CRYO-EM
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Synchronous enhancement of corrosion resistance and mechanical properties of Mg-Zn-Ca alloys by grain refinement using equal channel angular pressing 被引量:1
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作者 Yi-zhuo WANG Xiao-ping LUO +6 位作者 Gang-xiao REN Hong-xia WANG Li-fei WANG Wei-li CHENG Hang LI Xiao-peng LU Kwang-seon SHIN 《Transactions of Nonferrous Metals Society of China》 2025年第6期1772-1786,共15页
To investigate the effect of microstructure evolution on corrosion behavior and strengthening mechanism of Mg-1Zn-1Ca(wt.%)alloys,as-cast Mg-1Zn-1Ca alloys were performed by equal channel angular pressing(ECAP)with 1 ... To investigate the effect of microstructure evolution on corrosion behavior and strengthening mechanism of Mg-1Zn-1Ca(wt.%)alloys,as-cast Mg-1Zn-1Ca alloys were performed by equal channel angular pressing(ECAP)with 1 and 4 passes.The corrosion behavior and mechanical properties of alloys were investigated by optical microscopy(OM),scanning electron microscopy(SEM),electron backscatter diffraction(EBSD),electrochemical tests,immersion tests and tensile tests.The results showed that mechanical properties improved after ECAP 1 pass;however,the corrosion resistance deteriorated due to high-density dislocations and fragmented secondary phases by ECAP.In contrast,synchronous improvement in the mechanical properties and corrosion resistance was achieved though grain refinement after ECAP 4 passes;fine grains led to a significant improvement in the yield strength,ultimate tensile strength,elongation,and corrosion rate of 103 MPa,223 MPa,30.5%,and 1.5843 mm/a,respectively.The enhanced corrosion resistance was attributed to the formation of dense corrosion product films by finer grains and the barrier effect by high-density grain boundaries.These results indicated that Mg-1Zn-1Ca alloy has a promising potential for application in biomedical materials. 展开更多
关键词 Mg−1Zn−1Ca alloy equal channel angular pressing grain refinement corrosion behavior mechanical properties
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Flatness detection method of splicing detector based on channel spectral dispersion
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作者 ZHAO Hong-chao ZHANG Xiao-qian AN Qi-chang 《中国光学(中英文)》 北大核心 2025年第4期889-898,共10页
For segmented detectors,surface flatness is critical as it directly influences both energy resolution and image clarity.Additionally,the limited adjustment range of the segmented detectors necessitates precise benchma... For segmented detectors,surface flatness is critical as it directly influences both energy resolution and image clarity.Additionally,the limited adjustment range of the segmented detectors necessitates precise benchmark construction.This paper proposes an architecture for detecting detector flatness based on channel spectral dispersion.By measuring the dispersion fringes for coplanar adjustment,the final adjustment residual is improved to better than 300 nm.This result validates the feasibility of the proposed technology and provides significant technical support for the development of next-generation large-aperture sky survey equipment. 展开更多
关键词 large aperture telescope segmented detector surface wavefront detection channel spectral dispersion
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A Machine Learning-Based Channel Data Enhancement Platform for Digital Twin Channels
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作者 AI Bo ZHANG Yuxin +2 位作者 YANG Mi HE Ruisi GUO Rongge 《ZTE Communications》 2025年第2期20-30,共11页
Reliable channel data helps characterize the limitations and performance boundaries of communication technologies accurately.However,channel measurement is highly costly and time-consuming,and taking actual measuremen... Reliable channel data helps characterize the limitations and performance boundaries of communication technologies accurately.However,channel measurement is highly costly and time-consuming,and taking actual measurement as the only channel data source may reduce efficiency because of the constraints of high testing difficulty and limited data volume.Although existing standard channel models can generate channel data,their authenticity and diversity cannot be guaranteed.To address this,we use deep learning methods to learn the attributes of limited measured data and propose a generative model based on generative adversarial networks to rapidly synthesize data.A software simulation platform is also established to verify that the proposed model can generate data that are statistically similar to the measured data while maintaining necessary randomness.The proposed algorithm and platform can be applied to channel data enhancement and serve channel modeling and algorithm evaluation applications with urgent needs for data. 展开更多
关键词 channel measurement channel modeling deep learning data enhancement
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