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Rice use history in Southeast China:Phytolith evidence from the Nanshan site in Fujian Province

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Science China Earth Sciences 2023年第5期66卷 1108-1119页

作者： Qiuhe CHEN Zhao LI Yongchao MA zhenyu zhou Xiaoyan YANG Officers College of PAP ChinaChengdu610000China Key Laboratory of Land Surface Pattern and Simulation Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing100101China University of Chinese Academy of Sciences Beijing100049China Department of History Jinan UniversityGuangzhou510632China School of Archaeology and Museology Sichuan UniversityChengdu610065China Center for Archaeological Science Sichuan UniversityChengdu610065China National Demonstration Center for Experimental Archaeology Education Sichuan UniversityChengdu610065China Institute of Archaeology Chinese Academy of Social SciencesBeijing100710China Key Laboratory of Western China’s Environmental Systems Ministry of EducationCollege of Earth and Environmental SciencesLanzhou UniversityLanzhou730000China

The southern spread of rice agriculture is of great academic *** it already has a broad chronological framework,newly introduced rice use and its impact on local subsistence and ecological systems are still *** this study,we explore these issues by analysing phytoliths recovered from continuous sediments of Cave No.4 at the Nanshan site in Fujian Province,together with evidence from surrounding *** results show that rice was introduced into southeast China at 7,500 *** BP,but the dominance of the hunting-gathering system was not challenged until later,between 5,000 and 3,500 *** BP,when cultivation of rice,together with foxtail and broomcorn millets,was widely practiced in the *** suggests that mixed farming in Southeast China,likely originating around the middle Yangtze River,became widespread and gradually systematic during the previous two-millennium *** rice-millet mixed agricultural system changed the former hunting-gathering subsistence system,promoting the agriculturalization process,cultural prosperity and population growth,thus providing a solid basis for rice expansion and cultural migration to Southeast Asia.

关键词： Phytolith analysis Southward spread of rice agriculture Subsistence system China-Indo-China-Indo-China Peninsula Island Southeast Asia

PLC for In-Vehicle Network: A DRL-Based Algorithm of Diversity Combination of OFDM Subcarriers

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Chinese Journal of Electronics 2023年第6期32卷 1245-1257页

作者： CHEN Zhixiong ZHANG Zhikun CAO Tianshu zhou zhenyu School of Electrical and Electronic Engineering North China Electric Power University Hebei Key Laboratory of Power Internet of Things Technology

For low latency communication service of vehicles, it is critical to improve the delay performance of power line communication(PLC) for in-vehicle network,which can decrease the weight and cost of the vehicle. In order to minimize the total time slots used in a transmission task, an orthogonal frequency-division multiplexing(OFDM) subcarrier diversity combination algorithm of PLC based on the deep reinforcement learning(DRL) is proposed herein. The short packet communication theory is used to develop an optimal combination model with constraints on short packet reliability, transmitting power and the amount of data. The state, action, and reward function of double deep Q-learning network(DDQN) are defined, and diversity combination for OFDM subcarriers is performed using DDQN. An adaptive power allocation algorithm based on the thresholds of error rate and the data amount is used. Simulation results show that the proposed algorithm can effectively improve the delay performance of PLC under the constraints of power and data amount.

关键词： Q-learning OFDM Simulation Power line communications Reliability theory Delays Resource management

Investigation of Two-Dimensional Ultrasonic Surface Burnishing Process on 7075-T6 Aluminum

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Chinese Journal of Mechanical Engineering 2021年第1期34卷 224-240页

作者： zhenyu zhou Qiuyang Zheng Cong Ding Guanglei Yu Guangjian Peng Zhongyu Piao College of Mechanical Engineering Zhejiang University of TechnologyHangzhou 310012China Key Laboratory of Special Purpose Equipment and Advanced Processing Technology Ministry of Education and Zhejiang ProvinceZhejiang University of TechnologyHangzhou 310012China

A novel two-dimensional ultrasonic surface burnishing process(2D-USBP)is proposed.7075-T6 aluminum samples are processed by a custom-designed 2D-USBP *** optimization of 2D-USBP is conducted to determine the best processing strategy of 7075-T6 aluminum.A uniform design method is utilized to optimize the 2D-USBP process.U〔3(133)and 4(72)tables are established to conduct parameter *** depth,spindle speed,and feed rate are taken as the control *** surface roughness and Vickers hardness are taken as the evaluation *** establishes the active control models for surface *** wear tests are conducted to compare the wear-resistance of the 2D-USBP treated sample and the original *** show that the machining quality of 2D-USBP is best under 0.24 mm burnishing depth,5000 r/min spindle speed,and 25 mm/min feed *** surface roughness of the sample is reduced from 2517.758 to 50.878 nm,and the hardness of the sample surface is improved from 167 to 252 *** the lower load,the wear mechanism of the 2D-USBP treated sample is mainly abrasive wear accompanied by delamination wear,while the wear mechanism of the original sample is mainly delamination *** the higher load,the accumulation of frictional heat on the sample surface transforms the wear mechanisms of the original and the 2D-USBP treated samples into thermal wear.

关键词： Two-dimensional ultrasonic-assisted burnishing Uniform design Regression analysis Wear behavior

Evaluation of Surface Roughness of Aluminum Alloy in Burnishing Process Based on Chaos Theory

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Chinese Journal of Mechanical Engineering 2023年第1期36卷 90-103页

作者： Zhipeng Yuan zhenyu zhou Zhiguo Jiang Zeyu Zhao Cong Ding Zhongyu Piao College of Mechanical Engineering Zhejiang University of TechnologyHangzhou310012ZhejiangChina Key Laboratory of Special Purpose Equipment and Advanced Processing Technology Ministry of Education and Zhejiang ProvinceZhejiang University of TechnologyHangzhou310012China

Burnishing experiments with different burnishing parameters were performed on a computer numerical control milling machine to characterize the surface roughness of an aluminum alloy during *** chaos theory was employed to investigate the nonlinear features of the burnishing *** experimental results show that the power spectrum is broadband and continuous,and the Lyapunov exponentλis positive,proving that burnishing has chaotic *** chaotic characteristic parameter,the correlation dimension D,is sensitive to the time behavior of the system and is used to establish the corresponding relationship with the surface *** correlation dimension was the largest,when the surface roughness was the ***,when the correlation dimension curve decreases,the roughness curve *** correlation dimension and surface roughness exhibit opposite variation *** higher the correlation dimension,the lower the surface *** surface roughness of the aluminum alloy can be characterized online by calculating the correlation dimension during burnishing.

关键词： Aluminum alloy burnishing Power spectrum Correlation dimension Lyapunov exponent Surface roughness

Dynamical evolution of cross phase of edge fluctuations and transport bifurcation

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Plasma Science and Technology 2021年第4期23卷 15-20页

作者： Xueyun WANG zhenyu zhou Zhuoyi LI Bo LI School of Physics State Key Laboratory of Nuclear Physics and TechnologyPeking UniversityBeijing 100871People’s Republic of China School of Physics Beihang UniversityBeijing 100191People’s Republic of China

The dynamical evolution of edge turbulence during a transport bifurcation is explored using a flux-driven nonlinear fluid model with a geometry relevant to the plasma edge *** simulations show that the self-generated mean shear flows can dramatically modify the phase angle between turbulent *** changes in phase differences and amplitudes of edge fluctuations give rise to the modifications of turbulent edge *** statistical properties of flux and fluctuations are also investigated before and after edge shear flow generation.

关键词： plasma turbulence plasma edge transport plasma simulation

Endogenous Security-Aware Resource Management for Digital Twin and 6G Edge Intelligence Integrated Smart Park

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China Communications 2023年第2期20卷 46-60页

作者： Sunxuan Zhang Zijia Yao Haijun Liao zhenyu zhou Yilong Chen Zhaoyang You State Key Laboratory of Alternate Electrical Power System with Renewable Energy Sources(North China Electric Power University) Beijing 102206China Power Dispatching and Control Center of State Grid Shanghai Municipal Electric Power Company Shanghai 200122China

The integration of digital twin(DT)and 6G edge intelligence provides accurate forecasting for distributed resources control in smart ***,the adverse impact of model poisoning attacks on DT model training cannot be *** address this issue,we firstly construct the models of DT model training and model poisoning *** optimization problem is formulated to minimize the weighted sum of the DT loss function and DT model training ***,the problem is transformed and solved by the proposed Multi-timescAle endogenouS securiTy-aware DQN-based rEsouRce management algorithm(MASTER)based on DT-assisted state information evaluation and attack *** adopts multi-timescale deep Q-learning(DQN)networks to jointly schedule local training epochs and *** actively adjusts resource management strategies based on estimated attack probability to achieve endogenous security *** results demonstrate that MASTER has excellent performances in DT model training accuracy and delay.

关键词： smart park digital twin(DT) 6G edge intelligence resource management endogenous security awareness

Flexible memristors as electronic synapses for neuro- inspired computation based on scotch tape-exfoliated mica substrates

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Nano Research 2018年第3期11卷 1183-1192页

作者： Xiaobing Yan zhenyu zhou Jianhui Zhao Qi Liu Hong Wang Guoliang Yuan Jingsheng Chen College of Electron and Information Engineering Key Laboratory of Digital Medical Engineering of Hebei Province Key Laboratory of Optoelectronic Information Materials of Hebei Province Hebei University Baoding 071002 China Key Laboratory of Microelectronic Devices & Integrated Technology Institute of Microelectronics Chinese Academy of Sciences Beijing 100029 China School of Materials Science and Engineering Nanjing University of Science and Technology Nanjing 210094 China Department of Materials Science and Engineering National University of Singapore Singapore 117576 Singapore

Flexible memristor devices based on plastic substrates have attracted considerable attention due to their applications in wearable computers and integrated circuits. However, most plastic-substrate memristors cannot function or be grown in high-temperature environments. In this study, scotch-tape-exfoliated mica was used as the flexible memristor substrate in order to resolve these high-temperature issues. Our TiN/ZHO/IGZO memristor, which was constructed using a thin （10 μm） mica substrate, has superior flexibility and thermostability. After bending it 103 times, the device continues to exhibit exceptional electrical characteristics. It can also be implemented for transitions between high and low resistance states, even in temperatures of up to 300 ℃. More importantly, the biological synaptic characteristics of paired-pulse facilitation/depression （PPF/PPD） and spike- timing-dependent plasticity （STDP） were observed through applying different pulse measurement modes. This work demonstrates that flexible memristor devices on mica substrates may potentially allow for the realization of high-temperature memristor applications for biologically-inspired computing systems.

关键词： mica flexible memristor synapse

Disruption of MIR396e and MIR396f improves rice yield under nitrogen-deficient conditions

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National Science Review 2020年第1期7卷 102-112页

作者： Jinshan Zhang zhenyu zhou Jinjuan Bai Xiaoping Tao Ling Wang Hui Zhang Jian-Kang Zhu Shanghai Center for Plant Stress Biology and Center for Excellence in Molecular Plant Sciences Chinese Academy of Sciences University of Chinese Academy of Sciences School of Biotechnology Jiangsu University of Science and Technology Shanghai Engineering Research Center of Plant Germplasm Resources College of Life Science Shanghai Normal University Department of Horticulture and Landscape Architecture Purdue UniversityWest Lafayette

The microRNA miR396 directly represses GROWTH-REGULATING FACTORs(OsGRFs) and has been implicated in regulating rice yield and in nitrogen assimilation. Overexpressing the miR396 targets OsGRF4 and OsGRF6 improves rice yield via increased grain size and panicle branching, respectively. Here, we used CRISPR/Cas9 to assess the function of miR396 genes in rice. Knockout of MIR396 ef(MIR396e and MIR396f), but not other isoforms, enhanced both grain size and panicle branching, resulting in increased grain yield. Importantly, under nitrogen-deficient conditions, mir396ef mutants showed an even higher relative increase in grain yield as well as elevated above-ground biomass. Furthermore, we identified OsGRF8 as a new target of miR396, in addition to the known targets OsGRF4 and OsGRF6. Disruption of the miR396-targeting site in OsGRF8 was sufficient to both enlarge grain size and elongate panicles. Our results suggest that rice-seed and panicle development are regulated by miR396ef-GRF4/6/8-GIF1/2/3 modules and that mi R396ef are promising targets of genome editing for breeding environmentally friendly rice varieties that require less nitrogen fertilization.

关键词： microRNA miR396 OsGRF4/6/8 OsGIF1/2/3 nitrogen deficiency grain yield

One-step ethylene separation from ternary C_(2) hydrocarbon mixture with a robust zirconium metal-organic framework

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Chinese Journal of Chemical Engineering 2023年第7期59卷 9-15页

作者： Yuan Liu Hanting Xiong Jingwen Chen Shixia Chen zhenyu zhou Zheling Zeng Shuguang Deng Jun Wang School of Chemistry and Chemical Engineering Nanchang UniversityNanchang 330031China School for Engineering of Matter Transport and EnergyArizona State UniversityTempeAZ 85287United States

One-step separation of high-purity ethylene(C_(2)H_(4))from C_(2) hydrocarbon mixture is critical but challenging because of the very similar molecular sizes and physical properties of C_(2)H_(4),ethane(C_(2)H_(6)),and acetylene(C_(2)H_(2)).Herein,we report a robust zirconium metal-organic framework(MOF)Zr-TCA(H3TCA=4,4',4"-tricarboxytriphenylamine)with suitable pore size(0.6 nm×0.7 nm)and pore environment for direct C_(2)H_(4) purification from C_(2)H_(4)/C_(2)H_(2)/C_(2)H_(6) *** studies indicate that the abundant oxygen atoms and non-polar phenyl rings created favorable pore environments for the preferential binding of C_(2)H_(2) and C_(2)H_(6) over C_(2)H_(4).As a result,Zr-TCA exhibits not only high C_(2)H_(6)(2.28 mmol·g^(-1))and C_(2)H_(2)(2.78 mmol·g^(-1))adsorption capacity but also excellent C_(2)H_(6)/C_(2)H_(4)(2.72)and C_(2)H_(2)/C_(2)H_(4)(5.64)selectivity,surpassing most of one-step C_(2)H_(4) purification MOF *** breakthrough experiments confirm that Zr-TCA can produce high-purity C_(2)H_(4)(>99.9%)from a ternary gas mixture(1/9/90 C_(2)H_(2)/C_(2)H_(6)/C_(2)H_(4))in a single step with a high C_(2)H_(4) productivity of 5.61 L·kg^(-1).

关键词： Zirconium metal-organic framework Adsorption Separation One-step ethylene purification