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Efficient ORR catalysts for zinc-air battery: Biomass-derived ultra-stable Co nanoparticles wrapped with graphitic layers via optimizing electron transfer

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Journal of Energy Chemistry 2022年第7期31卷 211-218,I0006页

作者： Yu Feng Kexin Song Wei Zhang Xinyan Zhou Seung Jo Yoo Jin-Gyu Kim Sifan Qiao Yugang Qi Xu Zou Zhongjun Chen Tingting Qin Nailin Yue Zizhun Wang Dabing Li Weitao Zheng State Key Laboratory of Automotive Simulation and Control School of Materials Science&EngineeringKey Laboratory of Automobile Materials MOEElectron Microscopy Centerand International Center of Future ScienceJilin UniversityJilin UniversityChangchun 130012JilinChina Division of Scientific Instrumentation&Management Korea Basic Science InstituteDaejeon 34133Republic of Korea Institute of High Energy Physics Chinese Academy of SciencesBeijing 100049China State Key Laboratory of Luminescence and Applications Changchun Institute of OpticsFine Mechanics and PhysicsChinese Academy of SciencesChangchun 130033JilinChina

The poor stability of non-noble metal catalysts in oxygen reduction reaction(ORR) is a main bottleneck that limits their big-scale application in metal-air batteries. Herein, we construct a chainmail catalyst(Co-NC-AD) with outstanding stability, via the competitive complexation and post absorption strategy,consisting of highly graphitic layers wrapped uniform-size Co nanoparticles(Co-NPs). Experiments combined with density functional theory(DFT) calculations jointly confirmed that the electron transfer occurred from the inner Co-NPs to the external graphitic layers. It facilitated the adsorption process of oxygen molecules and the hybridization of the O-2 p and C-1 p orbitals, which accelerated the ORR reaction kinetics. Consequently, our prepared Co-NC-AD shows excellent ORR activity, offered with a more positive initial potential(E_(onset)= 0.95 V) and half-wave potential(E_(1/2)= 0.86 V). The remarkable stability and resistance of methanol poisoning are merited from the protection effect of stable graphitic layers. In addition, the high electrochemical performance of Co-NC-AD-based zinc-air battery demonstrates their potential for practical applications. Therefore, our work provides new ideas for the design of nanoconfined catalysts with high stability and activity.

关键词： Chainmail catalyst Graphitic layers Co nanoparticles Oxygen reduction reaction

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Speed planning and energy management strategy of hybrid electric vehicles in a car-following scenario

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Control Theory and Technology 2022年第2期20卷 185-196页

作者： Shengyan Hou Hong Chen Yu Zhang Jinwu Gao State Key Laboratory of Automotive Simulation and Control Jilin UniversityChangchun 130022JilinChina Department of Control Science and Engineering Jilin UniversityChangchun 130025JilinChina Department of Control Science and Engineering Tonji UniversityShanghai 200092China Suzhou Zhito Technology Co. Ltd.Suzhou 215129JiangsuChina

The development of intelligent connected technology has brought opportunities and challenges to the design of energy management strategies for hybrid electric ***,to achieve car-following in a connected environment while reducing vehicle fuel consumption,a power split hybrid electric vehicle was used as the research object,and a mathematical model including engine,motor,generator,battery and vehicle longitudinal dynamics is ***,with the goal of vehicle energy saving,a layered optimization framework for hybrid electric vehicles in a networked environment is *** speed planning problem is established in the upper-level controller,and the optimized speed of the vehicle is obtained and input to the lower-level ***,after the lower-level controller reaches the optimized speed,it distributes the torque among the energy sources of the hybrid electric vehicle based on the equivalent consumption minimum *** simulation results show that the proposed layered control framework can achieve good car-following performance and obtain good fuel economy.

关键词： Hybrid electric vehicle Car-following Speed planning Energy management strategy

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Analysis of HEMP Coupled Responses for RF Front-End Circuit of Wireless Communication Equipment

Analysis of HEMP Coupled Responses for RF Front-End Circuit ...

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2024 Photonics and Electromagnetics Research Symposium, PIERS 2024

作者： Zhang, Yinjie Du, Chuanbao Zhang, Mintao Ma, Wanzhi Mao, Congguang Nie, Xin Xihua University School of Electrical Engineering and Electronic Information Chengdu610039 China Northwest Institute of Nuclear Technology National Key Laboratory of Intense Pulsed Radiation Simulation and Effect Xi'an710024 China University of Electronic Science and Technology Chengdu611731 China

ISBN: (纸本)9798350375909

The ultra-short wave communication system primarily operates within the frequency spectrum of high-altitude electromagnetic pulses (HEMP), and its survivability is under serious threat. This article presents a research platform based on a software-defined radio architecture, which utilizes a typical superheterodyne RF receiver frontend circuit structure and possesses the characteristic features of a superheterodyne communication system. Using this platform, electromagnetic pulse irradiation tests on wireless communication devices and analysis of coupling response patterns were conducted. The platform monitors the coupling pulse waveform at various key component ports of the RF channel, allowing for the study of the propagation characteristics of pulse energy in the RF frontend of wireless communication devices under different irradiation waveform parameters. The article analyzes the differences in coupling waveforms at different RF component ports and the relationship between coupling pulses and energy propagation in the RF channel. It is found that when the low-noise amplifier (LNA) is in normal, degraded performance, and damaged states, the electromagnetic pulse response waveform parameters at critical RF component ports exhibit different characteristic parameters in the normal range, nonlinear range, and recovery range. This has important implications for the study of the impact of electromagnetic pulse shock on communication transmission performance. © 2024 IEEE.

关键词： Low noise amplifiers

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IMUSHIELD: Defending against inaudible attacks via IMUs on Smartphones 2

IMUSHIELD: Defending against inaudible attacks via IMUs on S...

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2nd International Conference on Electronic Information Technology, EIT 2023

作者： Zhang, Zhenfei Li, Ping Zhu, Biaokai Dong, Chong Lv, Zhao Anhui Province Key Laboratory of Multimodal Cognitive Computation School of Computer Science and Technology Anhui University Hefei230601 China Shanxi Police College China School of Electrical and Information Engineering Anhui University of Technology China

ISBN: (数字)9781510666627

ISBN: (纸本)9781510666610

Inaudible attack has brought growing concerns over security of voice assistants. With a well-designed inaudible signal, an adversary can force the voice assistant to execute commands inaudibly like "Siri, open the door". It is challenging to defend against ultrasonic attacks without modifying the hardware. In this paper, we proposed a light-weight system named IMUSHIELD to defend voice assistant against inaudible attack. By comparing the different response of signal from microphone and inertial measurement units (IMUs) to different frequencies on smartphones. IMUSHIELD is able to detect the attacks without modifying the hardware. We have prototyped our method on a number of smartphones and test the performance of IMUSHIELD comprehensively in the real world, the result shows that our average detection accuracy exceeded 90 %. © 2023 SPIE.

关键词： Smartphones

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Grey Prediction Based Input–Output Model for Analyzing Potential Energy-Related Emission Mitigation Pathways: A Case Study of Fujian 14th

Grey Prediction Based Input–Output Model for Analyzing Pote...

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14th International Conference on Environmental science and Technology, ICEST 2023

作者： Sun, Z.M. Liu, J. Li, Y.P. School of Environmental Science and Engineering Xiamen University of Technology Xiamen361024 China State Key Joint Laboratory of Environmental Simulation and Pollution Control School of Environment Beijing Normal University Beijing100875 China Faculty of Engineering and Applied Science University of Regina ReginaSKS4S 0A2 Canada

ISBN: (纸本)9783031546839

Economic activities release pollutants and carbon (mainly CO2) directly by consuming energy resources and indirectly by using energy-intensive goods. This research put forwards a grey model (GM) (1, 1) based input–output model (GIOM) for simulating pollutants and CO2 emissions in Fujian Province under varied socio-economic development scenarios. Major findings are: (i) in the planning period, Agriculture, forestry, animal husbandry and fishery (AGR) is the main sector for wastewater emissions in the planning period, and manufacturing and materials and energy conversion (MEC) sectors will be the main sectors for emissions of waste gases and CO2 in the planning period;(ii) through the simulation, the total energy consumption in Fujian Province increases by 13.53–51.08%, Metal and nonmetal products (MAN), MEC and Wholesale and retail transportation and warehousing (WRT) are the main energy consumers;(iii) the COD, NH3–N, SO2, and NOx emissions decrease 24.55–70.11%, 24.53–70.83%, 27.11–70.55% and 22.47–72.00% over time, and the CO2 emissions range from an increase of 36.35% to a decrease of 5.98% over time. © The Author(s), under exclusive license to Springer Nature Switzerland AG 2024.

关键词： Carbon dioxide

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Photoionisation detection of a single Er3+ ion with sub-100-ns time resolution

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National science Review 2024年第4期11卷 38-45页

作者： Yangbo Zhang Wenda Fan Jiliang Yang Hao Guan Qi Zhang Xi Qin Changkui Duan Gabriele G.de Boo Brett C.Johnson Jeffrey C.Mc Callum Matthew J.Sellars Sven Rogge Chunming Yin Jiangfeng Du CAS Key Laboratory of Microscale Magnetic Resonance and School of Physical Sciences University of Science and Technology of China CAS Center for Excellence in Quantum Information and Quantum Physics University of Science and Technology of China Hefei National Laboratory University of Science and Technology of China Centre of Excellence for Quantum Computation and Communication Technology School of Physics University of New South Wales Centre of Excellence for Quantum Computation and Communication Technology School of Engineering RMIT University Centre of Excellence for Quantum Computation and Communication Technology School of Physics University of Melbourne Centre of Excellence for Quantum Computation and Communication Technology Research School of Physics and Engineering Australian National University

Efficient detection of single optical centres in solids is essential for quantum information processing, sensing and single-photon generation *** this work,we use radio-frequency（RF） reflectometry to electrically detect the photoionisation induced by a single Er3+ion in *** high bandwidth and sensitivity of the RF reflectometry provide sub-100-ns time resolution for the photoionisation *** this technique,the optically excited state lifetime of a single Er3+ion in a Si nano-transistor is measured for the first time to be 0.49±0.04μ*** results demonstrate an efficient approach for detecting a charge state change induced by Er excitation and *** approach could be used for fast readout of other single optical centres in solids and is attractive for large-scale integrated optical quantum systems thanks to the multi-channel RF reflectometry demonstrated with frequency multiplexing techniques.

关键词： single optical centres erbium ions RF reflectometry photoionisation detection

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Injecting Revenue-awareness into Cold-start Recommendation: The Case of Online Insurance 29

Injecting Revenue-awareness into Cold-start Recommendation: ...

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29th IEEE International Conference on Parallel and Distributed Systems, ICPADS 2023

作者： Li, Yu Zhang, Yi Chang, Helen He Li, Qiang Jilin University College of Computer Science and Technology China Jilin University Key Laboratory of Symbolic Computation and Knowledge Engineering of Ministry of Education China WeSure Inc. Ping An Technology Shenzhen Co. Ltd China

ISBN: (纸本)9798350330717

In online insurance, one of the central challenges is the cold-starting of new insurance products, which means there are no previous samples to refer to. Previous studies have mainly focused on improving the prediction accuracy of new items, but they have failed to consider the revenue generated by existing items. As a result, the total revenue may suffer a loss even if new items get conversions. To address this issue, in this paper we propose RACRec, a Revenue-Aware Cold-start Recommendation framework for online insurance. Unlike previous works, RACRec uses a revenue-based objective function to ensure profitability when cold-starting new items. With this dedicated objective, RACRec orchestrates the cold-start and warm-start model by predicting their expected revenue from each user, thereby preserving the total profit. In order to accurately predict revenue, a double-ranking scheme is designed for the warm-start model to mitigate position bias, while an item embedding alignment algorithm is proposed for the cold-start model to learn the revenue of new items from similar old items. Furthermore, a reinforced orchestrate update scheme is designed to eliminate the impact of sparse conversions and continuously update revenue estimation. Extensive offline and online experiments have been conducted to validate the effectiveness of RACRec. © 2023 IEEE.

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Antecedent snowmelt and orographic precipitation contributions to water supply of Pakistan disastrous floods,2022

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Advances in Climate Change Research 2024年第3期15卷 419-430页

作者： Yan WANG Peng CUI Chen-Di ZHANG Guo-Tao ZHANG Jian-Sheng HAO Xu YUAN Yao-Zhi JIANG Lu WANG Key Laboratory of Land Surface Pattern and Simulation Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing 100101China Key Laboratory of Mountain Hazards and Earth Surface Process Institute of Mountain Hazards and EnvironmentChinese Academy of SciencesChengdu 610299China Polar and Marine Research Institute College of Harbor and Coastal EngineeringJimei UniversityXiamen 361021China School of Resources and Environment University of Electronic Science and Technology of ChinaChengdu 610054China Hebei Province Tangshan Caofeidian Meteorological Bureau Tangshan 063000China

In 2022,the Pakistan witnessed the hottest spring and wettest summer in *** devastating floods inundated a large portion of Pakistan and caused enormous ***,the primary water source and its contributions to these unprecedented floods remain *** on the reservoir inflow measurements,Multi-Source Weighted-Ensemble Precipitation(MSWEP),the fifth generation ECMWF atmospheric reanalysis(ERA5)products,this study quantified the contributions of monsoon precipitation,antecedent snow-melts,and orographic precipitation enhancement to floods in *** found that the Indus experienced at least four inflow up-rushes,which was mainly supplied by precipitation and snowmelt;In upper Indus,abnormally high temperature continued to influence the whole summer and lead to large amounts of snowmelts which not only was a key water supply to the flood but also provided favorable soil moisture conditions for the latter *** July,the snowmelt has higher contributions than the precipitation to the streamflow of Indus River,with contribution value of more than 60%.Moreover,the snowmelt could still supply 20%-40%water to the lower Indus in July and August;The leading driver of 2022 mega-floods over the southern Pakistan in July and August was dominated by the precipitation,where terrain disturbance induced precipitation account to approximately 33%over the southern *** results help to understand the mechanisms of flood formation,and to better predict future flood risks over complex terrain regions.

关键词： Extreme heavy rainfall Snowmelt Orographic precipitation Floods Pakistan

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Reliability-Aware Network Slicing based on Multi-Objective Optimization 13

Reliability-Aware Network Slicing based on Multi-Objective O...

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13th IEEE Congress on Evolutionary computation, CEC 2024

作者： Xia, Qiqi Wang, Jin Huang, Chengqiang Yao, Xin Southern University of Science and Technology Shenzhen China Southern University of Science and Technology Guangdong Key Laboratory of Brain-inspired Intelligent Computation Department of Computer Science and Engineering Shenzhen China Huawei Technologies Co. Ltd. Reliability Technology Lab Shenzhen China Lingnan University Department of Computing and Decision Sciences Hong Kong

ISBN: (纸本)9798350308365

Network slicing is an essential technology in 5G and the forthcoming 6G networks. It aims to embed multiple virtual networks, i.e., network slices, on top of a shared substrate network to meet diverse service requirements. While a considerable body of existing research strives to maximize overall profits by meeting the resource demands of the network slices, optimizing their reliability is frequently overlooked. In this paper, we formalize the network slicing problem as a multi-objective optimization problem that aims to maximize total profits and reliability of network slices. To tackle this problem, we propose a new multi-objective optimization approach that improves over the state-of-the-art algorithm, which can achieve good approximate Pareto front results balancing total profits and reliability of network slices. The performance of our proposed method is evaluated on both artificial and real-world network topologies. Experimental results demonstrate the superior performance of our proposed method compared to the baseline algorithm, outperforming the latter in 92% of instances in terms of the Hypervolume (HV) metric. © 2024 IEEE.

关键词： Optimization algorithms

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DMGA: A Directional-Mutation Genetic Algorithm for CDMS Problem of Kafka

DMGA: A Directional-Mutation Genetic Algorithm for CDMS Prob...

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IEEE International Conference on Networking, Sensing and Control

作者： Hanbo Ma Yaofei Ma Haitao Yuan Meijia Wang Jingwei Hu Yihuan Wang Hanbo Yang School of Automation Science and Electrical Engineering Beihang University Beijing China Beijing Simulation Center National Key Laboratory of Modeling and Simulation for Complex Systems Beijing China

ISBN: (数字)9798350365221

ISBN: (纸本)9798350365238

With the increasing role of distributed message systems (DMS) represented by Kafka in handling large-scale data streams, it is critical to improve system performance by optimizing configuration parameters in different production environments. Due to the target system possessing numerous configuration parameters and the complex interactions between them, parameter optimization becomes a complex and time-consuming process that relies heavily on human effort and an iterative trial-and-error approach. At present, this type of configuration parameter problem has been classified as the Configuration of Distributed Message Systems (CDMS) problem, for which the goal is to obtain the optimal set of parameters for achieving the best performance. In order to deal with this complex problem, an automatic optimization method is proposed in this paper, which combines an automatic script-based deployment and running framework with an improved Genetic Algorithm (GA) in cooperation with the Random Forest (RF) and statistical methods, named the Directional-Mutation Genetic Algorithm (DMGA). The framework and algorithm are designed to find the best configuration efficiently, obtaining optimal parameters accurately without human supervision. Actual results of comparison experiments based on the Kafka system show that the DMGA algorithm significantly improves the data throughput performance of Kafka, and its optimization speed is more efficient than the basic GA, highlighting its potential to quickly optimize Kafka's operational efficiency in different scenarios.

关键词： Statistical analysis System performance Production Throughput Sensors Tuning Streams Genetic algorithms Message systems Convergence

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