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SSRN 2022年

作者： Li, Xu Ma, Longlong Yan, Long Liu, Ziyue Liao, Yuhe Department of Thermal Science and Energy Engineering University of Science and Technology of China Hefei230026 China Key Laboratory of Energy Thermal Conversion and Process Measurement and Control of Ministry of Education School of Energy and Environment Southeast University Jiangsu Nanjing210096 China CAS Key Laboratory of Renewable Energy Guangzhou Institute of Energy Conversion Chinese Academy of Sciences Guangzhou510640 China

Catalytic hydrodeoxygenation (HDO) of oxygenated compounds under mild conditions is essential for chemical refining, which is always relied on improving hydrogenation activity or/and acid strength of catalytic system. Here, with the synthesis of functional TiO 2 (B) nanosheet, we developed a novel Pt/TiO 2 (B) catalyst for HDO of phenol. Through the synergistic effect of dispersed Pt isolated single atoms and nanoclusters, phenol was efficiently converted into cyclohexane without extra acid under 50 o C and atmospheric hydrogen. The catalytic diversity of two Pt species for C=O/C=C bonds leads to the formation of ketene/enol intermediates, as detected in the in-situ FT-IR tests. Due to the low C-O bond energy of enol intermediates, the HDO of phenol could be carried out at mild conditions through the implementable C-O bond cleavage of enol intermediates. This study provides a new understanding of green HDO process and a novel approach for HDO catalysts developing. © 2022, The Authors. All rights reserved.

关键词： Phenols

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Coverage Probability Analysis of RIS-Assisted High-Speed Train communications

arXiv

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arXiv 2022年

作者： Liu, Changzhu He, Ruisi Niu, Yong Ai, Bo Han, Zhu Ma, Zhangfeng Gao, Meilin Zhong, Zhangdui Wang, Ning State Key Laboratory of Rail Traffic Control and Safety Beijing Jiaotong University Beijing China Research Center of Networks and Communications Peng Cheng Laboratory Shenzhen China Department of Electrical and Computer Engineering University of Houston HoustonTX77004 United States Beijing National Research Center for Information Science and Technology Tsinghua University China School of Information Engineering Zhengzhou University Zhengzhou450001 China

Reconfigurable intelligent surface (RIS) has received increasing attention due to its capability of extending cell coverage by reflecting signals toward receivers. This paper considers a RIS-assisted high-speed train (HST) communication system to improve the coverage probability. We derive the closed-form expression of coverage probability. Moreover, we analyze impacts of some key system parameters, including transmission power, signal-to-noise ratio threshold, and horizontal distance between base station and RIS. Simulation results verify the efficiency of RIS-assisted HST communications in terms of coverage probability. Copyright © 2022, The Authors. All rights reserved.

关键词： Railroads

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Enhancement of quantum heat engine by encircling a Liouvillian exceptional point

arXiv

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arXiv 2023年

作者： Bu, J.-T. Zhang, J.-Q. Ding, G.-Y. Li, J.-C. Zhang, J.-W. Wang, B. Ding, W.-Q. Yuan, W.-F. Chen, L. Özdemir, S.K. Zhou, F. Jing, H. Feng, M. State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics Wuhan Institute of Physics and Mathematics Innovation Academy of Precision Measurement Science and Technology Chinese Academy of Sciences Wuhan430071 China University of the Chinese Academy of Sciences Beijing100049 China Research Center for Quantum Precision Measurement Guangzhou Institute of Industry Technology Guangzhou511458 China Department of Engineering Science and Mechanics Materials Research Institute Pennsylvania State University University Park State CollegePA16802 United States Key Laboratory of Low-Dimensional Quantum Structures and Quantum Control of Ministry of Education Department of Physics Synergetic Innovation Center for Quantum Effects and Applications Hunan Normal University Changsha410081 China School of Physics Zhengzhou University Zhengzhou450001 China

Quantum heat engines are expected to outperform the classical counterparts due to quantum coherences involved. Here we experimentally execute a single-ion quantum heat engine and demonstrate, for the first time, the dynamics and the enhanced performance of the heat engine originating from the Liouvillian exceptional points (LEPs). In contrast to the topological effects solely concerned for the LEPs, here we focus on the thermodynamic effects, which can be understood by the Landau-Zener-Stückelberg process under decoherence. We witness a positive net work from the quantum heat engine if the heat engine cycle dynamically encircles an LEP. Further investigation reveals that, under the same circumstance of the heat engine cycles, the largest net work occurs when the system is operated close to the LEP. We argue that our observation of the enhanced performance of the quantum heat engine benefits from the eigen-energy landscape close to the LEP and the topological transition induced by the LEP. Therefore, our results open a new possibility to explore the advantages of the LEPs in quantum systems from both the thermodynamic and topological aspects. © 2023, CC BY.

关键词： Topology

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A fluorescent fiber pH sensor for sensitive, wide-range detection using orange-emitting silicon quantum dots

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Analytica Chimica Acta 2025年 1368卷

作者： Dan Li Xiaolong Li Zijia Huang Tengteng Liu Mao Li Xiaoming Chen Na Li Yong Zhao School of Control Engineering Hebei Key Laboratory of Micro-Nano Precision Optical Sensing and Measurement Technology Northeastern University at Qinhuangdao Qinhuangdao 066004 China Guangdong Provincial Key Laboratory of Nanophotonic Functional Materials and Devices School of Optoelectronic Science and Engineering South China Normal University Guangzhou 510006 China College of Information Science and Engineering Northeastern University Shenyang 110819 China

pH value plays a vital role in biochemical analysis. To achieve online analysis, a new type of fluorescent fiber sensor has been developed for real-time, wide-range pH monitoring in biological and environmental fluids. The fluorescent fiber pH sensor was facilely created by immobilizing orange-emitting silicon quantum dots onto a tapered fiber probe through a photoinduced hydrogel polymerization technique. The sensor displays a specific response to pH variations, covering an extensive dynamic range from pH 3.0 to 12.0 with a resolution of 0.06/pH. Additionally, the sensor exhibited remarkable stability, repeatability, robustness, and reversibility. Especially, its high stability to ion strength and temperature fluctuations ensures reliable performance across various physiological and physical conditions. Furthermore, successful implementations of this sensor in detecting pH levels in real serum, artificial sweat and seawater samples further validate its accuracy, practicality and versatility. Overall, this sensor offers a practical and versatile tool for sensitive, real-time pH sensing in complex fluid environments, with great potential across multiple fields.

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Joint Sensing, Communication and Computation for Status Update in Mobile Edge Computing with Non-Orthogonal Multiple Access

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IEEE Internet of Things Journal 2025年

作者： Zhang, Jianfei Wang, Yufan Hu, Yun Chang, Zheng Qiqihar University College of Computer and Control Engineering Qiqihar161003 China Xidian University National Demonstration Center for Experimental Electronic Information and Communications Engineering Education Xi’an710071 China University of Electronic Science and Technology of China School of Computer Science and Engineering Chengdu611731 China University of Jyväskylä Faculty of Information Technology Jyväskylä40014 Finland

Mobile Edge Computing (MEC) is considered as a promising solution for augmenting the computational capabilities of Internet of Things (IoT) devices by offloading tasks to nearby edge servers (ESs). However, finite communication and computational resources at both IoT devices and ESs, coupled with escalating congestion as more devices connect, present critical challenges in maintaining low latency and high efficiency. In this work, we jointly design the task sensing, communication, and resource allocation for MEC with Non-Orthogonal Multiple Access (NOMA). To address the urgent need for timely data processing in IoT applications, we utilize the Age of Information (AoI) metric as a measure of data freshness. With the objective to minimize the system cost, we propose to jointly optimize sensing sampling intervals, sensing frequencies, offloading decision, and power allocation. Recognizing that this problem is NP-hard, we decompose it incrementally and propose a High-Dimensional Progressive Cost Optimization (HDPCO) algorithm to reduce overall system cost. Simulation results confirm the effectiveness of HDPCO, showing significant improvements in minimizing overall system cost compared to other proposed schemes. © 2014 IEEE.

关键词： Data reduction

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A Dynamic 3D Spontaneous Micro-expression Database: Establishment and Evaluation

arXiv

引用

arXiv 2021年

作者： Wang, Fengping Li, Jie Zhang, Siqi Qi, Chun Zhang, Yun Miao, Danmin The School of Information and Communications Engineering Xi'an Jiaotong University Xi'An China Xi'an Modern Control Technology Research Institute Xi'An China Xi'an Singularity One Information Technology Co. Xi'An China Department of Psychology Air Force Military Medical University Xi'An China

Micro-expressions are spontaneous, unconscious facial movements that show people's true inner emotions and have great potential in related fields of psychological testing. Since the face is a 3D deformation object, the occurrence of an expression can arouse spatial deformation of the face, but limited by the available databases are 2D videos, lacking the description of 3D spatial information of micro-expressions. In this paper, we proposed a new database that contains 373 micro-expression samples, each consisting of 2D video sequence and corresponding 3D point cloud sequence. These samples were classified using objective method based on facial action coding system, as well as non-objective emotion classification method combining video contents and participants' self-reports. We extracted 2D and 3D features using the local binary patterns on three orthogonal planes (LBP-TOP) and curvature algorithms, respectively, and evaluated the classification accuracies of these two features and their fusion results with leave-one-subject-out (LOSO) and 10-fold cross-validation. Further, we used various advanced neural network algorithms for database evaluation, the results show that classification accuracies are improved by fusing 3D features than using only 2D features. The database offers original and cropped micro-expression samples, which will facilitate the exploration and research on 3D spatio-temporal features of micro-expression. Copyright © 2021, The Authors. All rights reserved.

关键词： Database systems

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Generation of nanosecond 2.65μm pulses and pulse narrowing in fiber-bulk Ho3+:YAG laser pumped gain-switched Cr^2+:Cd Se laser

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Chinese Optics Letters 2020年第3期18卷 50-56页

作者： Hengkang Zhang Encai Ji Bin Zhang Yi Chen Baoquan Yao Qiang Liu Key Laboratory of Photonic Control Technology(Tsinghua University) Ministry of EducationBeijing 100084China State Key Laboratory of Precision Measurement Technology and Instruments Department of Precision InstrumentTsinghua UniversityBeijing 100084China School of Electronic and Information Engineering Harbin Institute of TechnologyShenzhen 518055China National Key Laboratory of Tunable Laser Technology Harbin Institute of TechnologyHarbin 150001China

The generation of mid-infrared pulsed lasers was achieved in a Ho3+:YAG laser pumped gain-switched Cr^2+:Cd Se laser system with the shortest pulse duration of 4.15 *** a pump pulse duration of 50 ns and pump power of 2.7 W,the gain-switched Cr^2+:Cd Se laser achieved over 10 times pulse narrowing,obtaining the maximum peak power of 5.7 k *** optical-to-optical conversion efficiency was 3.7%,which could be further improved with better crystal surface polishing *** laser central wavelength was measured to be 2.65μm with a bandwidth(FWHM)of 50 *** addition,the parameter optimization for suppressing the pulse tail was discussed,while the long cavity and high output transmissivity contributed to obtaining the single-peak pulses.

关键词： Cr^2+:CdSe laser gain-switching pulse narrowing mid-infrared

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Sensing Terminal for Big Data Oil and Gas Pipeline Corrosion Monitoring

Sensing Terminal for Big Data Oil and Gas Pipeline Corrosion...

引用

International Conference on Computer Network, Electronic and Automation (ICCNEA)

作者： Lin Li Yiding Wang School of Electronic Engineering Xi'an Shiyou University Shaanxi Provincial Key Lab of Oil and Gas Well Measurement and Control Technology Xi'an China

ISBN: (数字)9781728170831

ISBN: (纸本)9781728170848

Facing the construction requirements of big data pipelines, a distributed sensor terminal for multi-parameter monitoring of oil and gas pipeline anti-corrosion was designed. The terminal uses the microprocessor S3C2440A as the core, and several sensors form a multi-parameter sensor array monitoring circuit, and realizes the data transmission of the Internet of Things through the 4G DTU communication module and TCP protocol. The device can sense the temperature value, reference potential value, programmable power supply current and voltage output value of the long-distance pipeline in real time, and realize the data interaction with the cloud server. Tests show that the device is practical in realizing the application of big data pipeline monitoring value.

关键词： Pipelines Monitoring Temperature sensors Power supplies Oils Electric potential Temperature distribution

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Establishment and Application of Big Data Processing Platform

Establishment and Application of Big Data Processing Platfor...

引用

International Conference on Computer Network, Electronic and Automation (ICCNEA)

作者： Ruixia Liu Qizhi Zhang Xi'an Shiyou University School of Electrical Engineering Shaanxi Provincial Key Lab of Oil and Gas Well Measurement and Control Technology Xi'an China

ISBN: (数字)9781728170831

ISBN: (纸本)9781728170848

With the advent of the era of big data, more and more enterprises begin to use big data technology to deal with related analysis work. Hadoop is the dominant processing platform in the field of big data, an ecosystem that integrates distributed computing, storage, and management. The Spark framework, on the other hand, is a faster, more versatile distributed computing platform. However, it is only a computing platform and does not provide distributed storage and management per se, and computing remains dependent on distributed file system HDFS and cluster Resource Manager Yarn in the Hadoop ecosystem. Therefore, the combination of Spark and Hadoop to build a big data processing platform can better improve the algorithm efficiency and processing scale. This article explains the setup process and running state of Hadoop and Spark in detail, and verifies its feasibility through several ways.

关键词： Sparks Big Data Virtual machining Yarn Software Firewalls (computing) Optimized production technology

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Research on Dynamic Voltage Rise control Driven by IGBT

Research on Dynamic Voltage Rise Control Driven by IGBT

引用

International Conference on Computer Network, Electronic and Automation (ICCNEA)

作者： Yuntao Li Hailong Liu Lin Li School of Electronic Engineering Xi'an Shiyou University Shaanxi provincial key laboratory of oil and gas well measurement and control technology Xi'an China

ISBN: (数字)9781728170831

ISBN: (纸本)9781728170848

In order to suppress the turn-off voltage spikes caused by the turn-off of high-power insulated gate bi-polar transistors, a method of sampling the turn-off change rate through a small capacitor and performing closed-loop control is proposed. This circuit makes up for the defects of the traditional dynamic voltage rise control circuit that the magnification is not adjustable and shuts off the oscillation, which improves the stability and reliability of the circuit. Finally, through SABER simulation and experimental verification, the simulation results and experimental results confirm the feasibility of the program.

关键词： Insulated gate bipolar transistors Voltage control Integrated circuit modeling Clamps Threshold voltage Logic gates Oscillators

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