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The Roadmap of 2D Materials and Devices Toward Chips 被引量:3
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作者 Anhan Liu Xiaowei Zhang +16 位作者 Ziyu Liu Yuning Li Xueyang Peng Xin Li Yue Qin Chen Hu Yanqing Qiu Han Jiang Yang Wang Yifan Li Jun Tang Jun Liu Hao Guo Tao Deng Songang Peng He Tian Tian‑Ling Ren 《Nano-Micro Letters》 SCIE EI CAS CSCD 2024年第6期343-438,共96页
Due to the constraints imposed by physical effects and performance degra certain limitations in sustaining the advancement of Moore’s law.Two-dimensional(2D)materials have emerged as highly promising candidates for t... Due to the constraints imposed by physical effects and performance degra certain limitations in sustaining the advancement of Moore’s law.Two-dimensional(2D)materials have emerged as highly promising candidates for the post-Moore era,offering significant potential in domains such as integrated circuits and next-generation computing.Here,in this review,the progress of 2D semiconductors in process engineering and various electronic applications are summarized.A careful introduction of material synthesis,transistor engineering focused on device configuration,dielectric engineering,contact engineering,and material integration are given first.Then 2D transistors for certain electronic applications including digital and analog circuits,heterogeneous integration chips,and sensing circuits are discussed.Moreover,several promising applications(artificial intelligence chips and quantum chips)based on specific mechanism devices are introduced.Finally,the challenges for 2D materials encountered in achieving circuit-level or system-level applications are analyzed,and potential development pathways or roadmaps are further speculated and outlooked. 展开更多
关键词 Two-dimensional materials ROADMAP Integrated circuits Post-Moore era
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Task Offloading and Resource Allocation in NOMA-VEC:A Multi-Agent Deep Graph Reinforcement Learning Algorithm
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作者 Hu Yonghui Jin Zuodong +1 位作者 Qi Peng Tao Dan 《China Communications》 SCIE CSCD 2024年第8期79-88,共10页
Vehicular edge computing(VEC)is emerging as a promising solution paradigm to meet the requirements of compute-intensive applications in internet of vehicle(IoV).Non-orthogonal multiple access(NOMA)has advantages in im... Vehicular edge computing(VEC)is emerging as a promising solution paradigm to meet the requirements of compute-intensive applications in internet of vehicle(IoV).Non-orthogonal multiple access(NOMA)has advantages in improving spectrum efficiency and dealing with bandwidth scarcity and cost.It is an encouraging progress combining VEC and NOMA.In this paper,we jointly optimize task offloading decision and resource allocation to maximize the service utility of the NOMA-VEC system.To solve the optimization problem,we propose a multiagent deep graph reinforcement learning algorithm.The algorithm extracts the topological features and relationship information between agents from the system state as observations,outputs task offloading decision and resource allocation simultaneously with local policy network,which is updated by a local learner.Simulation results demonstrate that the proposed method achieves a 1.52%∼5.80%improvement compared with the benchmark algorithms in system service utility. 展开更多
关键词 edge computing graph convolutional network reinforcement learning task offloading
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Hybrid bonding of GaAs and Si wafers at low temperature by Ar plasma activation
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作者 Rui Huang Zhiyong Wang +3 位作者 Kai Wu Hao Xu Qing Wang Yecai Guo 《Journal of Semiconductors》 EI CAS CSCD 2024年第4期69-75,共7页
High-quality bonding of 4-inch GaAs and Si is achieved using plasma-activated bonding technology.The influence of Ar plasma activation on surface morphology is discussed.When the annealing temperature is 300℃,the bon... High-quality bonding of 4-inch GaAs and Si is achieved using plasma-activated bonding technology.The influence of Ar plasma activation on surface morphology is discussed.When the annealing temperature is 300℃,the bonding strength reaches a maximum of 6.2 MPa.In addition,a thermal stress model for GaAs/Si wafers is established based on finite element analysis to obtain the distribution of equivalent stress and deformation variables at different temperatures.The shape varia-tion of the wafer is directly proportional to the annealing temperature.At an annealing temperature of 400℃,the maximum protrusion of 4 inches GaAs/Si wafers is 3.6 mm.The interface of GaAs/Si wafers is observed to be dense and defect-free using a transmission electron microscope.The characterization of interface elements by X-ray energy dispersion spectroscopy indi-cates that the elements at the interface undergo mutual diffusion,which is beneficial for improving the bonding strength of the interface.There is an amorphous transition layer with a thickness of about 5 nm at the bonding interface.The preparation of Si-based GaAs heterojunctions can enrich the types of materials required for the development of integrated circuits,improve the performance of materials and devices,and promote the development of microelectronics technology. 展开更多
关键词 plasma-activated bonding bonding strength thermal stress model mutual diffusion
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Wireless Information and Power Transfer in Underwater Acoustic Sensor Networks
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作者 Feng Yizhi Ji Fei 《China Communications》 SCIE CSCD 2024年第10期256-266,共11页
Wireless information and power transfer(WIPT) enables simultaneously communications and sustainable power supplement without the erection of power supply lines and the replacement operation of the batteries for the te... Wireless information and power transfer(WIPT) enables simultaneously communications and sustainable power supplement without the erection of power supply lines and the replacement operation of the batteries for the terminals. The application of WIPT to the underwater acoustic sensor networks(UWASNs) not only retains the long range communication capabilities, but also provides an auxiliary and convenient energy supplement way for the terminal sensors, and thus is a promising scheme to solve the energy-limited problem for the UWASNs. In this paper, we propose the integration of WIPT into the UWASNs and provide an overview on various enabling techniques for the WIPT based UWASNs(WIPT-UWASNs) as well as pointing out future research challenges and opportunities for WIPT-UWASNs. 展开更多
关键词 underwater acoustic modem underwater acoustic sensor network(UWASN) wireless information and power transfer(WIPT)
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Targeted regeneration and upcycling of spent graphite by defect‐driven tin nucleation
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作者 Zhiheng Cheng Zhiling Luo +7 位作者 Hao Zhang Wuxing Zhang Wang Gao Yang Zhang Long Qie Yonggang Yao Yunhui Huang Kun Kelvin Fu 《Carbon Energy》 SCIE EI CAS CSCD 2024年第4期91-103,共13页
The recycling of spent batteries has become increasingly important owing to their wide applications,abundant raw material supply,and sustainable development.Compared with the degraded cathode,spent anode graphite ofte... The recycling of spent batteries has become increasingly important owing to their wide applications,abundant raw material supply,and sustainable development.Compared with the degraded cathode,spent anode graphite often has a relatively intact structure with few defects after long cycling.Yet,most spent graphite is simply burned or discarded due to its limited value and inferior performance on using conventional recycling methods that are complex,have low efficiency,and fail in performance restoration.Herein,we propose a fast,efficient,and“intelligent”strategy to regenerate and upcycle spent graphite based on defect‐driven targeted remediation.Using Sn as a nanoscale healant,we used rapid heating(~50 ms)to enable dynamic Sn droplets to automatically nucleate around the surface defects on the graphite upon cooling owing to strong binding to the defects(~5.84 eV/atom),thus simultaneously achieving Sn dispersion and graphite remediation.As a result,the regenerated graphite showed enhanced capacity and cycle stability(458.9 mAh g^(−1) at 0.2 A g^(−1) after 100 cycles),superior to those of commercial graphite.Benefiting from the self‐adaption of Sn dispersion,spent graphite with different degrees of defects can be regenerated to similar structures and performance.EverBatt analysis indicates that targeted regeneration and upcycling have significantly lower energy consumption(~99%reduction)and near‐zero CO_(2) emission,and yield much higher profit than hydrometallurgy,which opens a new avenue for direct upcycling of spend graphite in an efficient,green,and profitable manner for sustainable battery manufacture. 展开更多
关键词 battery recycling spent graphite targeted regeneration upcycling graphite
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Chlorine-Substituent Regulation in Dopant-Free Small-Molecule Hole-Transport Materials Improves the Effi ciency and Stability of Inverted Perovskite Solar Cells
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作者 Xinyi Liu Xiaoye Zhang +7 位作者 Zhanfeng Li Jinbo Chen Yanting Tian Baoyou Liu Changfeng Si Gang Yue Hua Dong Zhaoxin Wu 《Transactions of Tianjin University》 EI CAS 2024年第4期314-323,共10页
Although doped hole-transport materials(HTMs)off er an effi ciency benefi t for perovskite solar cells(PSCs),they inevi-tably diminish the stability.Here,we describe the use of various chlorinated small molecules,spec... Although doped hole-transport materials(HTMs)off er an effi ciency benefi t for perovskite solar cells(PSCs),they inevi-tably diminish the stability.Here,we describe the use of various chlorinated small molecules,specifi cally fl uorenone-triphenylamine(FO-TPA)-x-Cl[x=para,meta,and ortho(p,m,and o)],with diff erent chlorine-substituent positions,as dopant-free HTMs for PSCs.These chlorinated molecules feature a symmetrical donor-acceptor-donor structure and ideal intramolecular charge transfer properties,allowing for self-doping and the establishment of built-in potentials for improving charge extraction.Highly effi cient hole-transfer interfaces are constructed between perovskites and these HTMs by strategi-cally modifying the chlorine substitution.Thus,the chlorinated HTM-derived inverted PSCs exhibited superior effi ciencies and air stabilities.Importantly,the dopant-free HTM FO-TPA-o-Cl not only attains a power conversion effi ciency of 20.82% but also demonstrates exceptional stability,retaining 93.8%of its initial effi ciency even after a 30-day aging test conducted under ambient air conditions in PSCs without encapsulation.These fi ndings underscore the critical role of chlorine-substituent regulation in HTMs in ensuring the formation and maintenance of effi cient and stable PSCs. 展开更多
关键词 Hole-transport materials Inverted perovskite solar cells Chlorinated small molecules Donor–acceptor–donor structure
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Flight parameter calculation method of multi-projectiles using temporal and spatial information constraint 被引量:1
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作者 Han-shan Li Xiao-qian Zhang 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2023年第1期63-75,共13页
The dynamic parameters of multiple projectiles that are fired using multi-barrel weapons in highfrequency continuous firing modes are important indicators to measure the performance of these weapons.The characteristic... The dynamic parameters of multiple projectiles that are fired using multi-barrel weapons in highfrequency continuous firing modes are important indicators to measure the performance of these weapons.The characteristics of multiple projectiles are high randomness and large numbers launched in a short period of time,making it very difficult to obtain the real dispersion parameters of the projectiles due to the occlusion or coincidence of multiple projectiles.Using six intersecting-screen testing system,in this paper,we propose an association recognition and matching algorithm of multiple projectiles using a temporal and spatial information constraint mechanism.We extract the output signal from each detection screen and then use the wavelet transform to process the output signal.We present a method to identify and extract the time values on which the projectiles pass through the detection screens using the wavelet transform modulus maximum theory.We then use the correlation of the output signals of three parallel detection screens to establish a correlation coefficient recognition constraint function for the multiple projectiles.Based on the premise of linear projectile motion,we establish a temporal and spatial constraint matching model using the projectile’s position coordinates in each detection screen and the projectile’s time constraints within the multiple intersecting-screen geometry.We then determine the time values of the multiple projectiles in each detection screen using an iterative search cycle registration,and finally obtain the flight parameters for the multiple projectiles in the presence of uncertainty.The proposed method and algorithm were verified experimentally and can solve the problem of uncertainty in projectiles flight parameter under different multiple projectile firing states. 展开更多
关键词 Six detection screen array Multi-projectile Recognition and matching Temporal and spatial information constraint Wavelet transform
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Link Budget and Enhanced Communication Distance for Ambient Internet of Things
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作者 YANG Yibing LIU Ming +2 位作者 XU Rongtao WANG Gongpu GONG Wei 《ZTE Communications》 2024年第1期16-23,共8页
Backscatter communications will play an important role in connecting everything for beyond 5G(B5G)and 6G systems.One open challenge for backscatter communications is that the signals suffer a round-trip path loss so t... Backscatter communications will play an important role in connecting everything for beyond 5G(B5G)and 6G systems.One open challenge for backscatter communications is that the signals suffer a round-trip path loss so that the communication distance is short.In this paper,we first calculate the communication distance upper bounds for both uplink and downlink by measuring the tag sensitivity and reflection coefficient.It is found that the activation voltage of the envelope detection diode of the downlink tag is the main factor limiting the back-scatter communication distance.Based on this analysis,we then propose to implement a low-noise amplifier(LNA)module before the envelope detection at the tag to enhance the incident signal strength.Our experimental results on the hardware platform show that our method can increase the downlink communication range by nearly 20 m. 展开更多
关键词 ambient IoT(AIoT) B5G backscatter communication link budget low-noise amplifier(LNA) Release 19 tag chip sensitivity upper bounds
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The Appeals,Dilemmas,and Pathways of Enabling Rural Teachers’Professional Development Through Emerging Technologies
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作者 Hailang Chen Jianhua Huang 《Journal of Contemporary Educational Research》 2024年第5期240-246,共7页
With the rapid advancements in technology,especially in digitalization and intelligence,numerous modern technologies have poured into rural schools,effectively improving their informatization conditions.Nevertheless,t... With the rapid advancements in technology,especially in digitalization and intelligence,numerous modern technologies have poured into rural schools,effectively improving their informatization conditions.Nevertheless,these technologies remain detached from rural teachers,failing to significantly enhance the quality of education and teaching in rural areas.Rural education is a crucial aspect of ensuring balanced development in education.The question of how to enhance rural teachers’technological application abilities and fully leverage the positive role of technology in rural education and teaching has become a significant topic of current research on rural education issues.To better address this question,this study conducted a thorough examination of the specific appeals of rural teachers in the process of technology enablement.It was discovered that rural teachers generally face dilemmas such as insufficient technological application abilities,difficulties in obtaining quality teaching resources,and the lack of continuous technical support and update mechanisms.Based on these findings,specific pathways such as strengthening rural teacher training,optimizing the allocation of educational resources,and establishing mechanisms for continuous technical support and updates are proposed to aid in the high-quality development of rural education. 展开更多
关键词 Teacher professional development Emerging technologies Lifelong learning
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Matching while Learning: Wireless Scheduling for Age of Information Optimization at the Edge 被引量:2
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作者 Kun Guo Hao Yang +2 位作者 Peng Yang Wei Feng Tony Q.S.Quek 《China Communications》 SCIE CSCD 2023年第3期347-360,共14页
In this paper,we investigate the minimization of age of information(AoI),a metric that measures the information freshness,at the network edge with unreliable wireless communications.Particularly,we consider a set of u... In this paper,we investigate the minimization of age of information(AoI),a metric that measures the information freshness,at the network edge with unreliable wireless communications.Particularly,we consider a set of users transmitting status updates,which are collected by the user randomly over time,to an edge server through unreliable orthogonal channels.It begs a natural question:with random status update arrivals and obscure channel conditions,can we devise an intelligent scheduling policy that matches the users and channels to stabilize the queues of all users while minimizing the average AoI?To give an adequate answer,we define a bipartite graph and formulate a dynamic edge activation problem with stability constraints.Then,we propose an online matching while learning algorithm(MatL)and discuss its implementation for wireless scheduling.Finally,simulation results demonstrate that the MatL is reliable to learn the channel states and manage the users’buffers for fresher information at the edge. 展开更多
关键词 information freshness Lyapunov opti-mization multi-armed bandit wireless scheduling
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Deep Learning Applications Based on WISE Infrared Data:Classification of Stars,Galaxies and Quasars 被引量:1
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作者 Guiyu Zhao Bo Qiu +4 位作者 A-Li Luo Xiaoyu Guo Lin Yao Kun Wang Yuanbo Liu 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2023年第8期164-177,共14页
The Wide-field Infrared Survey Explorer(WISE)has detected hundreds of millions of sources over the entire sky.However,classifying them reliably is a great challenge due to degeneracies in WISE multicolor space and low... The Wide-field Infrared Survey Explorer(WISE)has detected hundreds of millions of sources over the entire sky.However,classifying them reliably is a great challenge due to degeneracies in WISE multicolor space and low detection levels in its two longest-wavelength bandpasses.In this paper,the deep learning classification network,IICnet(Infrared Image Classification network),is designed to classify sources from WISE images to achieve a more accurate classification goal.IICnet shows good ability on the feature extraction of the WISE sources.Experiments demonstrate that the classification results of IICnet are superior to some other methods;it has obtained 96.2%accuracy for galaxies,97.9%accuracy for quasars,and 96.4%accuracy for stars,and the Area Under Curve of the IICnet classifier can reach more than 99%.In addition,the superiority of IICnet in processing infrared images has been demonstrated in the comparisons with VGG16,GoogleNet,ResNet34,Mobile Net,EfficientNetV2,and RepVGG-fewer parameters and faster inference.The above proves that IICnet is an effective method to classify infrared sources. 展开更多
关键词 methods data analysis-techniques image processing-infrared GENERAL
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Recognition model and algorithm of projectiles by combining particle swarm optimization support vector and spatial-temporal constrain
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作者 Han-shan Li 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2023年第9期273-283,共11页
In order to improve the recognition rate and accuracy rate of projectiles in six sky-screens intersection test system,this work proposes a new recognition method of projectiles by combining particle swarm optimization... In order to improve the recognition rate and accuracy rate of projectiles in six sky-screens intersection test system,this work proposes a new recognition method of projectiles by combining particle swarm optimization support vector and spatial-temporal constrain of six sky-screens detection sensor.Based on the measurement principle of the six sky-screens intersection test system and the characteristics of the output signal of the sky-screen,we analyze the existing problems regarding the recognition of projectiles.In order to optimize the projectile recognition effect,we use the support vector machine and basic particle swarm algorithm to form a new recognition algorithm.We set up the particle swarm algorithm optimization support vector projectile information recognition model that conforms to the six sky-screens intersection test system.We also construct a spatial-temporal constrain matching model based on the spatial geometric relationship of six sky-screen intersection,and form a new projectile signal recognition algorithm with six sky-screens spatial-temporal information constraints under the signal classification mechanism of particle swarm optimization algorithm support vector machine.Based on experiments,we obtain the optimal penalty and kernel function radius parameters in the PSO-SVM algorithm;we adjust the parameters of the support vector machine model,train the test signal data of every sky-screen,and gain the projectile signal classification results.Afterwards,according to the signal classification results,we calculate the coordinate parameters of the real projectile by using the spatial-temporal constrain of six sky-screens detection sensor,which verifies the feasibility of the proposed algorithm. 展开更多
关键词 Six sky-screens intersection test system Pattern recognition Particle swarm optimization Support vector machine PROJECTILE
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Physical Layer Encryption of OFDM-PON Based on Quantum Noise Stream Cipher with Polar Code 被引量:1
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作者 Xu Yinbo Gao Mingyi +3 位作者 Zhu Huaqing Chen Bowen Xiang Lian Shen Gangxiang 《China Communications》 SCIE CSCD 2024年第3期174-188,共15页
Orthogonal frequency division multiplexing passive optical network(OFDM-PON) has superior anti-dispersion property to operate in the C-band of fiber for increased optical power budget. However,the downlink broadcast e... Orthogonal frequency division multiplexing passive optical network(OFDM-PON) has superior anti-dispersion property to operate in the C-band of fiber for increased optical power budget. However,the downlink broadcast exposes the physical layer vulnerable to the threat of illegal eavesdropping. Quantum noise stream cipher(QNSC) is a classic physical layer encryption method and well compatible with the OFDM-PON. Meanwhile, it is indispensable to exploit forward error correction(FEC) to control errors in data transmission. However, when QNSC and FEC are jointly coded, the redundant information becomes heavier and thus the code rate of the transmitted signal will be largely reduced. In this work, we propose a physical layer encryption scheme based on polar-code-assisted QNSC. In order to improve the code rate and security of the transmitted signal, we exploit chaotic sequences to yield the redundant bits and utilize the redundant information of the polar code to generate the higher-order encrypted signal in the QNSC scheme with the operation of the interleaver.We experimentally demonstrate the encrypted 16/64-QAM, 16/256-QAM, 16/1024-QAM, 16/4096-QAM QNSC signals transmitted over 30-km standard single mode fiber. For the transmitted 16/4096-QAM QNSC signal, compared with the conventional QNSC method, the proposed method increases the code rate from 0.1 to 0.32 with enhanced security. 展开更多
关键词 physical layer encryption polar code quantum noise stream cipher
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Spatial Modeling and Reliability Analyzing of Reconfigurable Intelligent Surfaces-Assisted Fog-RAN with Repulsion
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作者 Linlin Feng Zhizhong Zhang +2 位作者 Haonan Hu Errong Pei Yun Li 《China Communications》 SCIE CSCD 2023年第12期142-155,共14页
Reconfigurable Intelligent Surface(RIS),fog computing,and Cell-Free(CF)network architecture are three promising technologies for application to the Ultra-Reliable Low Latency Communication(URLLC)scenario in 6G mobile ... Reconfigurable Intelligent Surface(RIS),fog computing,and Cell-Free(CF)network architecture are three promising technologies for application to the Ultra-Reliable Low Latency Communication(URLLC)scenario in 6G mobile communication systems.This paper considers a RIS-assisted FogRadio Access Network(Fog-RAN)architecture where a)the repulsively distributed Fog-Access Points(FAPs)communicate in a CF manner to suppress intercell interference,b)RISs are introduced into the CF network to avoid shadowing and enhance the system performance,and c)fog computing evolved as cloud services providers at the edge of the network and an enabler for constructing a multi-layer computing power RAN.Then,we derive and validate the integral form of the maximum F-AP offloading probability and Successful Delivery Probability(SDP)of this RIS-assisted Fog-RAN over composite FisherSnedecor F fading,where the spatial effects are reconsidered with the assumption that the F-APs are modelled as a Beta Ginibre Point Process(β-GPP).The numeric and simulation results indicate that for the investigated RIS-assisted Fog-RAN,theβ-GPP-based deployment of F-APs can increase maximum of 8%of the SDP within the repulsion-effective range,compared with the Matern Cluster Process(MCP)-based ones.Also,deploying more RISs per F-AP offers more significant SDP improvements. 展开更多
关键词 β-GPP Fog-RAN reliability analysis RIS
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Caching modeling and energy analyzing of cell-free wireless heterogeneous networks with beta Ginibre point process
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作者 Linlin Feng Zhizhong Zhang +1 位作者 Haonan Hu Errong Pei 《Digital Communications and Networks》 SCIE CSCD 2023年第4期931-940,共10页
Cell-free Wireless Heterogeneous Networks(HetNets)have emerged as a technological alternative for conventional cellular networks.In this paper,we study the spatially correlative caching strategy,the energy analysis,an... Cell-free Wireless Heterogeneous Networks(HetNets)have emerged as a technological alternative for conventional cellular networks.In this paper,we study the spatially correlative caching strategy,the energy analysis,and the impact of parameter β on the total energy cost of the cell-free wireless HetNets with Access Points distributed by Beta Ginibre Point Process(β-GPP).We derive the approximate expression of Successful Delivery Probability(SDP)based on the Signal-to-Interference-plus-Noise Ratio coverage model.From both analytical and simulation results,it is shown that the proposed caching model based on β-GPP placement,which jointly takes into account path loss,fading,and interference,can closely simulate the caching performance of the cell-free HetNets in terms of SDP.By guaranteeing the outage probability constraints,the analytical expression of the uplink energy cost is also derived.Another conclusion is that with AP locations modeled by β-GPP,the power consumption is not sensitive to β,but is sensitive to the dimension of the kernel function;hence β is less restrictive,and only the truncation of the Ginibre kernel has to be appropriately modified.These findings are new compared with the existing literature where the nodes are commonly assumed to be of Poisson Point Process,Matern Hard-Core Process,or Poisson Cluster Process deployment in cell-free systems. 展开更多
关键词 Caching model Energy analysis Cell-free HetNets β-GPP
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Study of surface morphology in GaAs by hydrogen and helium implantation at elevated temperature
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作者 Rui Huang Zhiyong Wang +2 位作者 Hui Li Qing Wang Yecai Guo 《Journal of Semiconductors》 EI CAS CSCD 2023年第5期27-33,共7页
In this work,the surface morphology and internal defect evolution process of GaAs substrates implanted with light ions of different fluence combinations are studied.The influence of H and He ions implantation on the a... In this work,the surface morphology and internal defect evolution process of GaAs substrates implanted with light ions of different fluence combinations are studied.The influence of H and He ions implantation on the atomic mechanism of the blister phenomenon observed after annealing is investigated.Raman spectroscopy is used to measure the surface stress change of different samples before and after implantation and annealing.Optical microscopy and atomic force microscopy are used to characterize the morphology changes of the GaAs surface under different annealing conditions.The evolution of bubbles and defects in GaAs crystals is revealed by transmission electron microscopy.Through this study,it is hoped that ion implantation fluence,surface exfoliation efficiency and exfoliation cost can be optimized.At the same time,it also lays a foundation for the heterointegration of GaAs film on Si. 展开更多
关键词 IMPLANTATION surface ANNEALING
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Ligand Engineering in Tin-Based Perovskite Solar Cells
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作者 Peizhou Li Xiangrong Cao +9 位作者 Jingrui Li Bo Jiao Xun Hou Feng Hao Zhijun Ning Zuqiang Bian Jun Xi Liming Ding Zhaoxin Wu Hua Dong 《Nano-Micro Letters》 SCIE EI CAS CSCD 2023年第10期112-150,共39页
Perovskite solar cells(PSCs)have attracted aggressive attention in the photovoltaic field in light of the rapid increasing power conversion efficiency.However,their large-scale application and commercialization are li... Perovskite solar cells(PSCs)have attracted aggressive attention in the photovoltaic field in light of the rapid increasing power conversion efficiency.However,their large-scale application and commercialization are limited by the toxicity issue of lead(Pb).Among all the lead-free perovskites,tin(Sn)-based perovskites have shown potential due to their low toxicity,ideal bandgap structure,high carrier mobility,and long hot carrier lifetime.Great progress of Sn-based PSCs has been realized in recent years,and the certified efficiency has now reached over 14%.Nevertheless,this record still falls far behind the theoretical calculations.This is likely due to the uncontrolled nucleation states and pronounced Sn(Ⅳ)vacancies.With insights into the methodologies resolving both issues,ligand engineering-assisted perovskite film fabrication dictates the state-of-the-art Sn-based PSCs.Herein,we summarize the role of ligand engineering during each state of film fabrication,ranging from the starting precursors to the ending fabricated bulks.The incorporation of ligands to suppress Sn~(2+)oxidation,passivate bulk defects,optimize crystal orientation,and improve stability is discussed,respectively.Finally,the remained challenges and perspectives toward advancing the performance of Sn-based PSCs are presented.We expect this review can draw a clear roadmap to facilitate Sn-based PSCs via ligand engineering. 展开更多
关键词 PEROVSKITE Solar cells LEAD-FREE Ligand engineering DEFECTS Stability
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Status-Aware Resource Adaptation in Information-Centric and Software-Defined Network 被引量:1
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作者 嘉濡 陈哲 +1 位作者 罗洪斌 张宏科 《China Communications》 SCIE CSCD 2013年第12期66-76,共11页
In recent years, realising a "clean- state" design for the future Internet has become an important research focus. An architecture com- bining an Information-Centric Network (ICN) and Sottware-Defmed Network (SDN... In recent years, realising a "clean- state" design for the future Internet has become an important research focus. An architecture com- bining an Information-Centric Network (ICN) and Sottware-Defmed Network (SDN) (IC-SDN) has gradually attracted more attention. How- ever, the existing studies regarding IC-SDN still lack support in terms of the "network status awareness" function, resulting in unreasonable resource allocation. In this paper, we propose a new status-aware resource adaptation sche- me, i.e. a status-aware module is embedded into basic elements (Forwarding Node (FN) and Resource adaption Manager (RM)). The FNs collect the network status dynamically for the controller to reallocate network resources accor- ding to the fluctuations in environmental con- ditions. Simulation results show that, compared with the existing IC-SDN mechanism, the pro- posed scheme reduced the link bandwidth var- iance by 56% and the content delivery latency by 40%. The proof-of-concept implementation demonstrates the feasibility of our proposed sc- heme for small-scale deployment. 展开更多
关键词 ICN SDN status awareness re-source adaptation load balance LATENCY
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Virtual sample generation for model-based prognostics and health management of on-board high-speed train control system
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作者 Jiang Liu Baigen Cair +1 位作者 Jinlan Wang Jian Wang 《High-Speed Railway》 2023年第3期153-161,共9页
In view of class imbalance in data-driven modeling for Prognostics and Health Management(PHM),existing classification methods may fail in generating effective fault prediction models for the on-board high-speed train ... In view of class imbalance in data-driven modeling for Prognostics and Health Management(PHM),existing classification methods may fail in generating effective fault prediction models for the on-board high-speed train control equipment.A virtual sample generation solution based on Generative Adversarial Network(GAN)is proposed to overcome this shortcoming.Aiming at augmenting the sample classes with the imbalanced data problem,the GAN-based virtual sample generation strategy is embedded into the establishment of fault prediction models.Under the PHM framework of the on-board train control system,the virtual sample generation principle and the detailed procedures are presented.With the enhanced class-balancing mechanism and the designed sample augmentation logic,the PHM scheme of the on-board train control equipment has powerful data condition adaptability and can effectively predict the fault probability and life cycle status.Practical data from a specific type of on-board train control system is employed for the validation of the presented solution.The comparative results indicate that GAN-based sample augmentation is capable of achieving a desirable sample balancing level and enhancing the performance of correspondingly derived fault prediction models for the Condition-based Maintenance(CBM)operations. 展开更多
关键词 High-speed railway Prognostics and health management Train control Virtual sample Generative adversarial network
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Competition between two kinds of information among random-walking individuals 被引量:1
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作者 刘真真 王兴元 王茂基 《Chinese Physics B》 SCIE EI CAS CSCD 2012年第4期625-630,共6页
A model is proposed to describe the competition between two kinds of information among N random-walking individuals in an L x L square, starting from a half-and-half mixture of two kinds of information. Individuals re... A model is proposed to describe the competition between two kinds of information among N random-walking individuals in an L x L square, starting from a half-and-half mixture of two kinds of information. Individuals remain or change their information according to their neighbors' information. When the moving speed of individuals v is zero, the two kinds of information typically coexist, and the ratio between them increases with L and decreases with N. In the dynamic case (v 〉 0), only one information eventually remains, and the time required for one information being left scales as Td -v^αL^β^γ. 展开更多
关键词 information spread random walk complex networks power law
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