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Response of maize growth and soil biological characteristics to planting density under fertigation in a semi-arid region

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International Journal of Agricultural and Biological Engineering 2024年第2期17卷 186-192页

作者： Peng Jiang Lei Li Dejia Xu Rui wang quan Sun School of Forestry and Prataculture Ningxia UniversityYinchuan 750021China Institute of Agricultural Resources and Environment Ningxia Academy of Agriculture and Forestry SciencesYinchuan 750002China School of Agriculture Ningxia UniversityYinchuan 750021China

Increasing the planting density can exacerbate crop competition for water,nutrients and space which results in a decline in the crop ***,the effect of increasing planting density on crop growth and soil biological characteristics in barren sandy land in the semi-arid regions are still *** this study,we investigated the effects of six planting densities(5.4×10^(4),6.45×10^(4),7.95×10^(4),9.5×10^(4),9.75×10^(4) and 10.5×10^(4) plants/hm^(2))on maize growth,photosynthesis characteristics,yield and soil biological characteristics in barren sandy soil in the semi-arid region of Ningxia,*** results indicated that the stem diameter and spike length decreased linearly with increasing planting *** plant height,spike weight,grain weight and 100-grain weight decreased with increasing plating ***,the root length increased with increasing planting *** diameter,volume and activity increased and then decreased with increasing planting *** was no significant difference(p>0.05)in the effect of planting density on transpiration rate intercellular CO_(2) *** well,the soil microbial biomass carbon and microbial biomass nitrogen decreased with increasing planting *** soil catalase activities increased and then decreased with increasing planting *** alkaline phosphatase activity,the amounts of soil bacteria and actinomycetes increased with increasing planting ***,a moderately increasing planting density can improve maize yield when water and nutrients are *** optimal planting density was 8.29×10^(4) plants/hm^(2) and the highest yield was 15.84 t/hm^(2) in barren sandy soil in semi-arid region of Ningxia,*** study provides a theoretical basis for high yield and high efficiency of maize.

关键词： maize growth planting density yield fertigation soil enzyme activity

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Enhancing personalized exercise recommendation with student and exercise portraits

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Journal of Electronic Science and Technology 2024年第2期22卷 91-109页

作者： Wei-Wei Gao Hui-Fang Ma Yan Zhao Jing wang quan-Hong Tian College of Computer Science and Engineering Northwest Normal UniversityLanzhou730070China Computer Center of Gansu Province Lanzhou730070China

The exercise recommendation system is emerging as a promising application in online learning scenarios,providing personalized recommendations to assist students with explicit learning *** solutions generally follow a collaborative filtering paradigm,while the implicit connections between students(exercises)have been largely *** this study,we aim to propose an exercise recommendation paradigm that can reveal the latent connections between student-student(exercise-exercise).Specifically,a new framework was proposed,namely personalized exercise recommendation with student and exercise portraits(PERP).It consists of three sequential and interdependent modules:Collaborative student exercise graph(CSEG)construction,joint random walk,and recommendation list ***,CSEG is created as a unified heterogeneous graph with students’response behaviors and student(exercise)***,a joint random walk to take full advantage of the spectral properties of nearly uncoupled Markov chains is performed on CSEG,which allows for full exploration of both similar exercises that students have finished and connections between students(exercises)with similar ***,we propose to optimize the recommendation list to obtain different exercise *** analyses of two public datasets,the results demonstrated that PERP can satisfy novelty,accuracy,and diversity.

关键词： Educational data mining Exercise recommend Joint random walk Nearly uncoupled Markov chains Optimization Personalized learning

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Adhesive Contact of Elastic Solids with Self-Affine Fractal Rough Surfaces

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Acta Mechanica Solida sinica 2024年第2期37卷 265-270页

作者： Xuan-Ming Liang Shi-Wen Chen si-He wang Zhen-Yuan Gong Jun Feng Gang-Feng wang Department of Engineering Mechanics SVL and MMMLXi’an Jiaotong UniversityXi’an710049China OPPO Mobile Telecommunications Corporation Ltd. Dongguan523860China

The elastic adhesive contact of self-affine fractal rough surfaces against a rigid flat is simulated using the finite element method. An array of nonlinear springs, of which the force-separation law obeys the Lennard–Jones potential, is introduced to account for the interfacial adhesion. For fractal rough surfaces, the interfacial interaction is generally attractive for large mean gaps, but turns repulsive as the gap continuously shrinks. The interfacial interactions at the turning point corresponding to the spontaneous contact are shown for various surfaces. For relatively smooth surfaces, the probability density distributions of repulsion and attraction are nearly symmetric. However, for rougher surfaces, the simulation results suggest a uniform distribution for attraction but a monotonously decreasing distribution with a long tail for repulsion. The pull-off force rises with increasing ratio of the work of adhesion to the equilibrium distance, whereas decreases for solids with a higher elastic modulus and a larger surface roughness. The current study will be helpful for understanding the adhesion of various types of rough solids.

关键词： Fractal rough surfaces Adhesion Contact mechanics Lennard-Jones potential

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Enhancement of Ising superconductivity in monolayer NbSe_(2) via surface fluorination

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Science China(Technological Sciences) 2024年第7期67卷 2099-2106页

作者： WU JiZheng SHI WuJun wang Chong DUAN WenHui XU Yong si Chen School of Materials Science and Engineering Beihang UniversityBeijing 100191China Center for Transformative Science ShanghaiTech UniversityShanghai 201210China Shanghai High Repetition Rate XFEL and Extreme Light Facility(SHINE) ShanghaiTech UniversityShanghai 201210China State Key Laboratory of Low Dimensional quantum Physics and Department of Physics Tsinghua UniversityBeijing 100084China Frontier Science Center for quantum Information Beijing 100084China

Recently discovered Ising superconductors have garnered considerable interest due to their anomalously large in-plane upper critical fields(B_(c2)). However, the requisite strong spin-orbital coupling in the Ising pairing mechanism generally renders these superconductors heavy-element dominant with notably low superconducting transition temperatures(Tc). Here, based on the Migdal-Eliashberg theory and the mean-field Bogoliubov-de Gennes Hamiltonian, we demonstrate a significant enhancement of Ising superconductivity in monolayer NbSe_(2) through surface fluorination, as evidenced by concomitant improvements in Tcand Bc_(2). This enhancement arises from three predominant factors. Firstly, fluorine atoms symmetrically and stably adhere to both sides of the monolayer NbSe_(2), thereby maintaining the out-of-plane mirror symmetry and locking carrier spins ***, fluorination suppresses the charge density wave in monolayer NbSe_(2) and induces a van Hove singularity in the vicinity of the Fermi level, leading to a marked increase in the number of carriers and, consequently, strengthening the electron-phonon coupling(EPC). Lastly, the appearance of fluorine-related, low-frequency phonon modes further augments the EPC. Our findings suggest a promising avenue to elevate Tcin two-dimensional Ising superconductors without compromising their Ising pairing.

关键词： Ising superconductivity surface functionalization upper critical field NbSe_(2) first-principles calculations

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Ground state of Rydberg-dressed Bose gas confined in a toroidal trap

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Communications in Theoretical Physics 2024年第1期76卷 29-35页

作者： Lin-Xue wang Hong-Li Yang Hui Liu si-Lin Chen Ya-Jun wang Xiao-Fei Zhang Department of Physics School of Physics and Information ScienceShaanxi University of Science and TechnologyXi'an 710021China Department of Basic Sciences Air Force Engineering UniversityXi'an 710051China

The experimental realization of Rydberg dressing technology in ultracold atomic systems provides another superior platform for studying novel states of matter and macroscopic quantum *** this work,based on the mean-field theory,we have investigated the ground-state phases of a two-component Bose–Einstein condensate with Rydberg interaction and confined in a toroidal *** effects of the Rydberg interaction and external potential,especially the Rydberg blockade radius,on the ground-state structure of such a system have been investigated in full parameter *** results show that the Rydberg blockade radius,which can be regarded as another controllable parameter,can be used to obtain a variety of ground-state *** interestingly,it is found that for weak Rydberg interactions,the Rydberg blockade radius breaks the spontaneous rotational symmetry of the system,leading to the formation of a discrete unit cell *** strongly interacting cases,it can be used to realize different orders of discrete rotational symmetry breaking.

关键词： Bose-Einstein condensate Rydberg dressing toroidal trap

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Noise‐tolerant matched filter scheme supplemented with neural dynamics algorithm for sea island extraction

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CAAI Transactions on Intelligence Technology 2024年第4期9卷 996-1013页

作者： Yiyu Chen Dongyang Fu Difeng wang Haoen Huang Yang si Shangfeng Du School of Electronics and Information Engineering Guangdong Ocean UniversityZhanjiangChina State Key Laboratory of Satellite Ocean Environment Dynamics Second Institute of OceanographyMinistry of Natural ResourcesHangzhouChina School of Artificial Intelligence and Automation Huazhong University of Science and TechnologyWuhanChina

Achieving high‐precision extraction of sea islands from high‐resolution satellite remote sensing images is crucial for effective resource development and sustainable ***,achieving such accuracy for sea island extraction presents significant challenges due to the presence of extensive background interference.A more widely applicable noise‐tolerant matched filter(NTMF)scheme is proposed for sea island extraction based on the MF *** NTMF scheme effectively suppresses the background interference,leading to more accurate and robust sea island *** further enhance the accuracy and robustness of the NTMF scheme,a neural dynamics algorithm is supplemented that adds an error integration feedback term to counter noise interference during internal computer operations in practical *** comparative experiments were conducted on various remote sensing images of sea islands under different noisy working conditions to demonstrate the superiority of the proposed neural dynamics algorithm‐assisted NTMF *** experiments confirm the ad-vantages of using the NTMF scheme for sea island extraction with the assistance of neural dynamics algorithm.

关键词： edge detection image classification image recognition shape extraction

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Parallel System Based quantitative Assessment and Self-evolution for Artificial Intelligence of Active Power Corrective Control

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CSEE Journal of Power and Energy Systems 2024年第1期10卷 13-28页

作者： Tianyun Zhang Jun Zhang Feiyue wang Peidong Xu Tianlu Gao Haoran Zhang Ruiqi si School of Electrical Engineering and Automation Wuhan UniversityWuhan 430072HubeiChina State Key Laboratory for Management and Control of Complex System Institute of AutomationChinese Academy of SciencesBeijing 100190China

In artificial intelligence(AI)based-complex power system management and control technology,one of the urgent tasks is to evaluate AI intelligence and invent a way of autonomous intelligence ***,there is,currently,nearly no standard technical framework for objective and quantitative intelligence *** this article,based on a parallel system framework,a method is established to objectively and quantitatively assess the intelligence level of an AI agent for active power corrective control of modern power systems,by resorting to human intelligence evaluation *** this basis,this article puts forward an AI self-evolution method based on intelligence assessment through embedding a quantitative intelligence assessment method into automated reinforcement learning(AutoRL)systems.A parallel system based quantitative assessment and self-evolution(PLASE)system for power grid corrective control AI is thereby constructed,taking Bayesian Optimization as the measure of AI evolution to fulfill autonomous evolution of AI under guidance of their intelligence assessment *** results exemplified in the power grid corrective control AI agent show the PLASE system can reliably and quantitatively assess the intelligence level of the power grid corrective control agent,and it could promote evolution of the power grid corrective control agent under guidance of intelligence assessment results,effectively,as well as intuitively improving its intelligence level through selfevolution.

关键词： AI quantitative intelligence assessment and self-evolution automated reinforcement learning Bayesian optimization corrective control parallel system

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Bi-doped carbon quantum dots functionalized liposomes with fluorescence visualization imaging for tumor diagnosis and treatment

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Chinese Chemical Letters 2024年第4期35卷 414-419页

作者： Peide Zhu Yangjia Liu Yaoyao Tang siqi Zhu Xinyang Liu Lei Yin quan Liu Zhiqiang Yu quan Xu Dixian Luo Juncheng wang State Key Laboratory of Heavy Oil Processing China University of Petroleum-BeijingBeijing 102249China Department of Laboratory Medicine Dongguan Institute of Clinical Cancer ResearchAffiliated Dongguan HospitalSouthern Medical UniversityDongguan 523058China Department of Laboratory Medicine Huazhong University of Science and Technology Union Shenzhen Hospital(Nanshan Hospital)Shenzhen 518052China Institute of Stomatology First Medical CenterChinese PLA General HospitalBeijing 100853China

Liposomes are one of the significant classes of antitumor nanomaterials and the most successful nanomedicine drugs in clinical translation. However, it is difficult to accurately reveal liposome delivery modes and drug release rates at different p H values to assess the biodistribution and drug delivery pathways in vivo. Here, we established a strategy to integrate Bi-doped carbon quantum dots(CQDs)with liposomes to produce fluorescence visualization and therapeutic effects, namely lipo/Bi-doped ***/Bi-doped CQDs show good water solubility and physicochemical properties, which can be used for in vitro labeling of colon cancer(CT26) cells and in vivo imaging localization tracking tumors for monitoring. simultaneously, thanks to the excellent p H sensitivity and ion doping characteristic of Bi-doped CQDs, lipo/Bi-doped CQDs can be used to reveal the drug release rate of liposomes at different p H values and exhibit potential effects in vivo antitumor therapy.

关键词： Bi-doped CQDs Lipo/Bi-doped CQDs pH sensitivity In vitro/in vivo imaging Diagnosis and treatment integration

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A Multi-Strategy-Improved Northern Goshawk Optimization Algorithm for Global Optimization and Engineering Design

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Computers, Materials & Continua 2024年第7期80卷 1677-1709页

作者： Liang Zeng Mai Hu Chenning Zhang quan Yuan Shanshan wang School of Electrical and Electronic Engineering Hubei University of TechnologyWuhan430068China Hubei Key Laboratory for High-Efficiency Utilization of Solar Energy and Operation Control of Energy Storage System Hubei University of TechnologyWuhan430068China

Optimization algorithms play a pivotal role in enhancing the performance and efficiency of systems across various scientific and engineering *** enhance the performance and alleviate the limitations of the Northern Goshawk Optimization(NGO)algorithm,particularly its tendency towards premature convergence and entrapment in local optima during function optimization processes,this study introduces an advanced Improved Northern Goshawk Optimization(INGO)*** algorithm incorporates a multifaceted enhancement strategy to boost operational ***,a tent chaotic map is employed in the initialization phase to generate a diverse initial population,providing high-quality feasible ***,after the first phase of the NGO’s iterative process,a whale fall strategy is introduced to prevent premature convergence into local *** is followed by the integration of T-distributionmutation strategies and the State Transition Algorithm(STA)after the second phase of the NGO,achieving a balanced synergy between the algorithm’s exploitation and *** research evaluates the performance of INGO using 23 benchmark functions alongside the IEEE CEC 2017 benchmark functions,accompanied by a statistical analysis of the *** experimental outcomes demonstrate INGO’s superior achievements in function optimization ***,its applicability in solving engineering design problems was verified through simulations on Unmanned Aerial Vehicle(UAV)trajectory planning issues,establishing INGO’s capability in addressing complex optimization challenges.

关键词： Northern Goshawk Optimization tent chaotic map T-distribution disturbance state transition algorithm UAV path planning

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Construction of daily precipitation series and the observational characteristics of extreme precipitation in Tianjin,China during 1888-2022

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Advances in Climate Change Research 2024年第1期15卷 52-61页

作者： Peng si Qing-Xiang LI Xiao-Yang CHEN Min wang Chuan-Jun LUO Tianjin Meteorological Information Center Tianjin Meteorological BureauTianjin 300074China Research Centerfor Ecology and Environment of Central Asia Chinese Academy of SciencesWulumuqi 830011China School of Atmospheric Sciences Sun Yat-sen UniversityZhuhai 528478China Key Laboratory of Tropical Amosphere-Ocean System Ministry of EducationZhuhai 528478China Shaoguan Meteorological Service Shaoguan 512028China

Given the difficulties in rescuing and ensuring the quality of long-term climate data,current studies on century-scale climate change are usually limited to annual and monthly data,resulting in the poor detection of extreme climate events and their changes before *** this study,we reconstructed a daily precipitation series for Tianjin from 15 September 1887 to 31 December 2022 on the basis of the most comprehensive daily precipitation records collected from the Tianjin Meteorological Archive,China,and in reference to the precipitation analysis results based on the datasets developed by the Climatic Research Unit Time-Series version 4.06,Global Precipitation Climatology Centre and University of Delaware along with the application of various homogenisation methods for climate *** approach provides a complete and reliable century-long daily precipitation series for the study of regional or local extreme weather and climate *** reconstructed daily dataset reveals that the annual precipitation amount and R95 intensity in Tianjin during 1888-2022 lack significant trends and have values of 0.74±6.99 and-1.84±3.22 mm per decade,*** the annual and seasonal scales,the precipitation amount and R95 intensity,particularly those in autumn,have increased since the latter half of the 20th century relative to those in ***,the increase in precipitation amount and R95 intensity is relatively limited compared with that in atmospheric water vapour content due to surface warming,indicating the highly sensitive response of extreme precipitation events to *** addition,the estimates for the return periods of 5,10,20,50 and 100 years covering 1888-2022,1888-1950 and 1951-2022 depict that the intensity of heavy rain and above magnitude was highest in 1888-1950 and decreased in 1951-2022.

关键词： Over a century-long timescale Daily precipitation series Extreme precipitation Return period

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