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Design and implementation of ethernet passive electronic network over coax
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作者 黄晶 Liu Deming 《High Technology Letters》 EI CAS 2013年第3期290-294,共5页
To increase the limit of ethernet over coax (EoC) technology in the bidirectional reform of the hybrid fiber coaxial (HFC) network, an ethernet passive electronic network (EPEN) system based on Coax is proposed ... To increase the limit of ethernet over coax (EoC) technology in the bidirectional reform of the hybrid fiber coaxial (HFC) network, an ethernet passive electronic network (EPEN) system based on Coax is proposed and experimentally demonstrated in this paper. The proposed EPEN exploits the existing capabilities of the MAC layer in the ethernet passive optical network (EPON) for reduction of cost of the HFC network. As the MPCP (multi-point control protocol) is introduced in the EPEN, bandwidth control and higher efficiency can be achieved. The experimental results exhibit the throughput of system up to 100Mbps, which meet the requirements of HFC network. To improve the performance of EPEN, frequency division multiplexing (FDM) can be used for further increase of the throughput and more hardware processing modules in the future. can be implemented to enhance the capacity 展开更多
关键词 ethernet over coax EoC ethernet passive electronic network EPEN) ethernetpassive optical network (EPON) multi-point control protocol (MPCP)
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AQSIQ Popularizing Nation-wide Launching of Electronic Network for Product Quality Supervision
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《China Standardization》 2006年第3期43-44,共2页
According to AQSIQ, it has made an effort to popularize the launching ofelectronic ''network for product quality supervision in the whole nation. China Product QualitySupervision Electronic Network is a nation... According to AQSIQ, it has made an effort to popularize the launching ofelectronic ''network for product quality supervision in the whole nation. China Product QualitySupervision Electronic Network is a nation-wide network, which employs modern informationtechnology, network technology and encoding technology to supervise enterprises'' products in anelectronic way. The new system labels digital information on all items of products that are includedin the network. 展开更多
关键词 NATION WORK NET AQSIQ Popularizing Nation-wide Launching of electronic network for Product Quality Supervision
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Tungsten oxide/nitrogen-doped carbon nanotubes composite catalysts for enhanced redox kinetics in lithium-sulfur batteries
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作者 Deqing He Zihao Xie +2 位作者 Qian Yang Wei Wang Chao Su 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2024年第3期58-67,共10页
The sluggish redox kinetics of polysulfides in lithium-sulfur(Li-S)batteries are a significant obstacle to their widespread adoption as energy storage devices.However,recent studies have shown that tungsten oxide(WO_(... The sluggish redox kinetics of polysulfides in lithium-sulfur(Li-S)batteries are a significant obstacle to their widespread adoption as energy storage devices.However,recent studies have shown that tungsten oxide(WO_(3))can facilitate the conversion kinetics of polysulfides in Li-S batteries.Herein,we fabricated host materials for sulfur using nitrogen-doped carbon nanotubes(N-CNTs)and WO_(3).We used low-cost components and simple procedures to overcome the poor electrical conductivity that is a disadvantage of metal oxides.The composites of WO_(3) and N-CNTs(WO_(3)/N-CNTs)create a stable framework structure,fast ion diffusion channels,and a 3D electron transport network during electrochemical reaction processes.As a result,the WO_(3)/N-CNT-Li2S6 cathode demonstrates high initial capacity(1162 mA·h·g^(-1) at 0.5℃),excellent rate performance(618 mA·h·g^(-1) at 5.5℃),and a low capacity decay rate(0.093%up to 600 cycles at 2℃).This work presents a novel approach for preparing tungsten oxide/carbon composite catalysts that facilitate the redox kinetics of polysulfide conversion. 展开更多
关键词 Li-S batteries Composites Ion diffusion channels 3D electron transport network Redox kinetics
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Robust digital receiver for EPC sensor network 被引量:1
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作者 Cheng Jin Sung Ho Cho 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2013年第1期44-51,共8页
A robust digital receiver based on a matched filter (MF) is proposed for the radio frequency identification (RFID) reader system to enhance the reliability of signal processing in the electronic product code (EPC... A robust digital receiver based on a matched filter (MF) is proposed for the radio frequency identification (RFID) reader system to enhance the reliability of signal processing in the electronic product code (EPC) sensor network (ESN). The performance of the proposed receiver is investigated by examining the anti-collision algorithm in the EPC global Class1 Generation2 protocol. The validity and usefulness are demonstrated by both computer simulations and experiments. Based on the verification results, comparing with the conventional zero crossing detector (ZCD) based receiver, the proposed receiver is very robust against strong amplitude distortions and considerable frequency deviations happening on the backscattered signal from a passive tag. 展开更多
关键词 electronic product code (EPC) sensor network (ESN) signal distortion matched filter radio frequency identification (RFID) receiver.
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A regional GNSS-VTEC model over Nigeria using neural networks: A novel approach
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作者 Daniel Okoh Oluwafisavo Owolabi +5 位作者 Christovher Ekechukwu Olanike Folarin Gila Arhiwo Joseph Agbo Segun Bolaji Babatunde Rabiu 《Geodesy and Geodynamics》 2016年第1期19-31,共13页
A neural network model of the Global Navigation Satellite System - vertical total electron content (GNSS-VTEC) over Nigeria is developed. A new approach that has been utilized in this work is the consideration of th... A neural network model of the Global Navigation Satellite System - vertical total electron content (GNSS-VTEC) over Nigeria is developed. A new approach that has been utilized in this work is the consideration of the International Reference Ionosphere's (IRI's) critical plasma frequency (foF2) parameter as an additional neuron for the network's input layer. The work also explores the effects of using various other input layer neurons like distur- bance storm time (DST) and sunspot number. All available GNSS data from the Nigerian Permanent GNSS Network (NIGNET) were used, and these cover the period from 2011 to 2015, for 14 stations. Asides increasing the learning accuracy of the networks, the inclusion of the IRI's foF2 parameter as an input neuron is ideal for making the networks to learn long-term solar cycle variations. This is important especially for regions, like in this work, where the GNSS data is available for less than the period of a solar cycle. The neural network model developed in this work has been tested for time-varying and spatial per- formances. The latest 10% of the GNSS observations from each of the stations were used to test the forecasting ability of the networks, while data from 2 of the stations were entirely used for spatial performance testing. The results show that root-mean-squared-errors were generally less than 8.5 TEC units for all modes of testing performed using the optimal network. When compared to other models, the model developed in this work was observed to reduce the prediction errors to about half those of the NeQuick and the IRI model. 展开更多
关键词 Global Navigation Satellite System(GNSS) ionosphereTotal electron content (TEC)Nigerian permanent GNSS network(NIGNET)Neural networkInternational reference ionosphere(IRI)
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CNTs@S composite as cathode for all-solid-state lithium-sulfur batteries with ultralong cycle life 被引量:7
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作者 Qiang Zhang Ning Huang +3 位作者 Zhen Huang Liangting Cai Jinghua Wu Xiayin Yao 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2020年第1期151-155,I0006,共6页
The main challenges in development of traditional liquid lithium-sulfur batteries are the shuttle effect at the cathode caused by the polysulfide and the safety concern at the Li metal anode arose from the dendrite fo... The main challenges in development of traditional liquid lithium-sulfur batteries are the shuttle effect at the cathode caused by the polysulfide and the safety concern at the Li metal anode arose from the dendrite formation.All-solid-state lithium-sulfur batteries have been proposed to solve the shuttle effect and prevent short circuits.However,solid-solid contacts between the electrodes and the electrolyte increase the interface resistance and stress/strain,which could result in the limited electrochemical performances.In this work,the cathode of all-solid-state lithium-sulfur batteries is prepared by depositing sulfur on the surface of the carbon nanotubes(CNTs@S)and further mixing with Li10GeP2S12 electrolyte and acetylene black agents.At 60℃,CNTs@S electrode exhibits superior electrochemical performance,delivering the reversible discharge capacities of 1193.3,959.5,813.1,569.6 and 395.5 mAhg^-1 at the rate of 0.1,0.5,1,2 and 5 C,respectively.Moreover,the CNTs@S is able to demonstrate superior high-rate capability of 660.3 mAhg^-1 and cycling stability of 400 cycles at a high rate of 1.0 C.Such uniform distribution of the CNTs,S and Li10GeP2S12 electrolyte increase the electronic and ionic conductivity between the cathode and the electrolyte hence improves the rate performance and capacity retention. 展开更多
关键词 CNTs@S composite All-solid-state lithium-sulfur battery electronic conduction network Interfacial contact Ultralong cycle life
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XPS and Raman studies of electron irradiated sodium silicate glass 被引量:1
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作者 陈亮 王铁山 +3 位作者 张根发 杨坤杰 彭海波 张利民 《Chinese Physics B》 SCIE EI CAS CSCD 2013年第12期352-357,共6页
The microstructure modifications of sodium silicate glass induced by 1.2-MeV electron irradiation are studied by x-ray photoelectron spectroscopy and Raman spectroscopy. Depth profile analyses are also performed on th... The microstructure modifications of sodium silicate glass induced by 1.2-MeV electron irradiation are studied by x-ray photoelectron spectroscopy and Raman spectroscopy. Depth profile analyses are also performed on the irradiated glass at 109 Gy. A sodium-depleted layer with a thickness of a few tens of nanometers and the corresponding increase of network polymerization on the top surface are observed after electron bombardment, while the polymerization in the subsurface region has a negligible variation with the irradiation dose. Moreover, the formation of molecular oxygen after electron irradiation is evidenced, which is mainly aggregated in the first two-micron-thick irradiated glass surface. These modifications are correlated to the network relaxation process as a consequence of the diffusion and desorption of sodium species during electron irradiation. 展开更多
关键词 silicate glass electron irradiation network polymerization oxygen molecule
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Instruction to Authors 被引量:1
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《Journal of Shanghai University(English Edition)》 CAS 2005年第6期F0003-F0003,共1页
关键词 Statement of the Editorial Board on Entering electronic Journals and Periodicals networks
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Security and Privacy Issues in Electronic Health Network
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作者 MA Yan LIU Jianwei LIU Weiran 《Wuhan University Journal of Natural Sciences》 CAS 2013年第6期523-529,共7页
Electronic health network (EHN) is an information system providing functions involved in e-health. In this paper, we devise mechanisms covering three important security and privacy issues of EHN including trust mana... Electronic health network (EHN) is an information system providing functions involved in e-health. In this paper, we devise mechanisms covering three important security and privacy issues of EHN including trust management, privacy preserving, and data sharing. First, we propose an authenticated key agreement scheme based on hierarchical identity-based signature (HIBS). We abstract a hierarchical architecture from the social network architecture of EHN. To support large-scale scenarios, we introduce a virtual signature generation phase into traditional HIBS, thus our scheme will be efficient even the depth is quite big. Second, we propose a fast data searching scheme based on symmetric searchable encryption (SSE). To improve the searching efficiency, we introduce a two-level cache structure into the traditional SSE. Third, we propose an access control scheme based on hierarchical identity- based encryption (HIBE). To make it a fine-grained scheme, we organize the data owner's file in hierarchy and introduce a virtual key generation phase to traditional HIBE. Also, the scheme can provide delegation and revocation functions easily, Besides, our schemes guarantee known-key secrecy, forward secrecy, and antidirection secrecy and possess the resistance capability to collude-attack. Evaluation results show that our scheme indeed achieves the security and efficiency. 展开更多
关键词 electronic health network (EHN) trust management privacy preserving data sharing
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