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A new scheme of climate-vegetation regionalization in the Hengduan Mountains Region

Science China Earth Sciences 2024年第3期67卷 751-768页

作者： xueqin ZHANG Xiaoming xu Xiang LI Peng CUI Du zheng Key Laboratory of Land Surface Pattern and Simulation Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing 100101China University of Chinese Academy of Sciences Beijing 100049China China-Pakistan Joint Research Center on Earth Sciences Chinese Academy of Sciences-Higher Education Commission of PakistanIslamabad 45320Pakistan

The Hengduan Mountains Region(HMR) is essential for the future ecological protection, clean energy production,Sichuan-Xizang and Yunnan-Xizang railways, and other major infrastructure projects in China. The distributions of climate and vegetation exhibit significant regional differentiation and vertical zonality due to the rugged longitudinal ranges and gorges and the complex disaster-prone environments in HMR. Therefore, it is urgent to develop the climate-vegetation regionalization in HMR to effectively satisfy the national requirements such as agricultural production and ecological protection, mountain disaster risk prevention, and major project construction. We here develop a new scheme of climate-vegetation regionalization with the latest demarcation outcome of HMR, the ground observation from 122 meteorological stations in HMR and its surrounding areas during 1990–2019, and the high-precision remote sensing data of land cover types. The new scheme first constructs the regionalization index system, fully considering the extraordinarily complicated geomorphic pattern of mountains and valleys, the scarcity of meteorological observations, and the remarkable differentiation of climate and vegetation in HMR. The system consists of three primary regionalization indices(i.e., days with daily average temperature steady above 10°C, aridity index, and main vegetation types, dividing the temperature zones, moisture regions, and vegetation subregions, respectively) and three auxiliary indices of the accumulated temperature above 10°C, and the temperatures in January and July. Then, the HMR is divided into five temperature zones, 20 moisture regions, and 55 vegetation subregions. Compared with previous regionalization schemes, the new scheme optimizes the climate spatial interpolation model of thin plate smoothing spline suitable for the unique terrain in HMR. Moreover, the disputed division index threshold between different climatic zones(regions) is scientifically clarifi

关键词： Climate-vegetation regionalization Thin plate smoothing spline(TPSS) GeoDetector Stepwise downscaling pane division method Hengduan Mountains Region

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Variational quantum algorithms for scanning the complex spectrum of non-Hermitian systems

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Frontiers of physics 2024年第4期19卷 275-285页

作者： xu-Dan Xie zheng-Yuan xue Dan-Bo Zhang Key Laboratory of Atomic and Subatomic Structure and Quantum Control(Ministry of Education) Guangdong Basic Research Center of Excellence for Structure and Fundamental Interactions of Matterand School of PhysicsSouth China Normal UniversityGuangzhou 510006China Guangdong Provincial Key Laboratory of Quantum Engineering and Quantum Materials Guangdong–Hong Kong Joint Laboratory of Quantum Matterand Frontier Research Institute for PhysicsSouth China Normal UniversityGuangzhou 510006China

Solving non-Hermitian quantum many-body systems on a quantum computer by minimizing the variational energy is challenging as the energy can be ***,we propose a variational quantum algorithm for solving the non-Hermitian Hamiltonian by minimizing a type of energy variance,where zero variance can naturally determine the eigenvalues and the associated left and right ***,the energy is set as a parameter in the cost function and can be tuned to scan the whole spectrum efficiently by using a two-step optimization *** numerical simulations,we demonstrate the algorithm for preparing the left and right eigenstates,verifying the biorthogonal relations,as well as evaluating the *** also investigate the impact of quantum noise on our algorithm and show that its performance can be largely improved using error mitigation ***,our work suggests an avenue for solving non-Hermitian quantum many-body systems with variational quantum algorithms on near-term noisy quantum computers.

关键词： quantum algorithm non-Hermitian physics quantum manybody systems

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Compact CubeSat Gamma-ray detector for GRID mission

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Nuclear Science and Techniques 2021年第9期32卷 105-115页

作者： Jia-Xing Wen xu-tao zheng Jian-Dong Yu Yue-Peng Che Dong-Xin Yang Huai-Zhong Gao Yi-Fei Jin Xiang-Yun Long Yi-Hui Liu Da-Cheng xu Yu-Chong Zhang Ming Zeng Yang Tian Hua Feng Zhi Zeng Ji-Rong Cang Qiong Wu Zong-Qing Zhao Bin-Bin Zhang Peng An GRID collaboration Key Laboratory of Particle and Radiation Imaging(Tsinghua University) Ministry of EducationBeijing 100084China Department of Engineering Physics Tsinghua UniversityBeijing 100084China Science and Technology on Plasma Physics Laboratory Laser Fusion Research CenterCAEPMianyang 621900China School of Electronic and Information Engineering Ningbo University of TechnologyNingbo 315201China Department of Astronomy Tsinghua UniversityBeijing 100084China Department of Physics Tsinghua UniversityBeijing 100084China Key Laboratory of Modern Astronomy and Astrophysics(Nanjing University) Ministry of EducationNanjing 210093China Nanjing University School of Astronomy and Space SciencesNanjing 210093China

Gamma-Ray Integrated Detectors(GRID)mis-sion is a student project designed to use multiple gamma-ray detectors carried by nanosatellites(CubeSats),forming a full-time all-sky gamma-ray detection network that monitors the transient gamma-ray sky in the multi-mes-senger astronomy era.A compact CubeSat gamma-ray detector,including its hardware and firmware,was designed and implemented for the *** detector employs four Gd 2 Al 2 Ga 3 O 12:Ce(GAGG:Ce)scintillators coupled with four silicon photomultiplier(SiPM)arrays to achieve a high gamma-ray detection efficiency between 10 keV and 2 MeV with low power and small *** first detector designed by the undergraduate student team onboard a commercial CubeSat was launched into a Sun-synchronous orbit on October 29,*** detector was in a normal observation state and accumulated data for approximately one month after on-orbit functional and performance tests,which were conducted in 2019.

关键词： Gamma-ray bursts Scintillation detectors SiPM CubeSat

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Associations of daily sedentary behavior,physical activity,and sleep with irritable bowel syndrome:A prospective analysis of 362,193 participants

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Journal of Sport and Health Science 2024年第1期13卷 72-80页

作者： xu Gao Sifan Tian Ninghao Huang Gang Sun tao Huang Department of Occupational and Environmental Health Sciences School of Public HealthPeking UniversityBeijing 100191China Department of Epidemiology and Biostatistics School of Public HealthPeking UniversityBeijing 100191China Department of Gastroenterology and Hepatology First Medical Center of People's Liberation Army General HospitalBeijing 100853China

Background:Irritable bowel syndrome(IBS)substantially affects quality of life and requires early *** study aimed to elucidate the relationships between IBS and daily behaviors,including sedentary behavior(SB),physical activity(PA),and *** particular,it seeks to identify healthy behaviors to reduce IBS risk,which previous studies have rarely ***:Daily behaviors were retrieved from self-reported data of 362,193 eligible UK Biobank *** cases were determined by self-report or health care data according to RomeⅣ***:A total of 345,388 participants were IBS-free at baseline,during a median follow-up of 8.45 years,19,885 incident IBS cases were *** examined individually,SB and shorter(≤7 h/day)or longer(>7 h/day)sleep duration were each positively associated with increased IBS risk,and PA was associated with lower IBS *** isotemporal substitution model suggested that replacing SB with other activities could provide further protective effects against IBS *** people sleeping≤7 h/day,replacing 1 h of SB with equivalent light PA,vigorous PA,or sleep was associated with 8.1%(95%confidence interval(95%CI):0.901-0.937),5.8%(95%CI:0.896-0.991),and 9.2%(95%CI:0.885-0.932)reduced IBS risk,*** people sleeping>7 h/day,light and vigorous PA were associated with a 4.8%(95%CI:0.926-0.978)and a 12.0%(95%CI:0.815-0.949)lower IBS risk,*** benefits were mostly independent of genetic risk for ***:SB and unhealthy sleep duration are risk factors for IBS.A promising way to mitigate IBS risk for individuals sleeping≤7 h/day and for those sleeping>7 h/day appears to be by replacing SB with adequate sleep or vigorous PA,respectively,regardless of the genetic predisposition of IBS.

关键词： Irritable bowel syndrome Isotemporal substitution model Physical activity Sedentary behavior Sleep

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Collective Movement Simulation:Methods and Applications

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Machine Intelligence Research 2024年第3期21卷 452-480页

作者： Hua Wang Xing-Yu Guo Hao tao Ming-Liang xu School of Computer and Artificial Intelligence Zhengzhou UniversityZhengzhou450001China Engineering Research Center of Intelligent Swarm Systems Ministry of EducationZhengzhou450001China National Supercomputing Center in zhengzhou Zhengzhou450001China China Ship Development and Design Center Wuhan430060China

Collective movement simulations are challenging and important in many areas,including life science,mathematics,physics,information science and public *** this survey,we provide a comprehensive review of the state-of-the-art techniques for collective movement *** start with a discussion on certain concepts to help beginners understand it more ***,we analyze the intelligence among different collective objects and the emphasis in different ***,we classify existing collective movement simulation methods into four categories according to their effects,namely versatility,accuracy,dynamic adaptability,and assessment feedback ***,we introduce five applications of layout optimization,emergency control,dispatching,unmanned systems,and other derivative ***,we summarize possible future research directions.

关键词： Collective movement simulation multiple objects multiple discipline simulation effect collective intelligence

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Molecular dynamics study of hydrogen-induced cracking behavior of ferrite–pearlite gas transmission pipeline steel

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Journal of Iron and Steel Research International 2024年第2期31卷 488-500页

作者： tao-long xu Si-han Guo Gong-zhen He Hao-yu Han Petroleum Engineering School Southwest Petroleum UniversityChengdu610500SichuanChina Sichuan East Gas Transmission Sales Center of Sinopec Natural Gas Branch Wuhan430074HubeiChina

Hydrogen embrittlement of pipelines depends on the hydrogen-induced cracking behavior of the pipeline steel *** on molecular dynamics analysis,the ferrite–cementite(α-Fe/Fe3C)lamellar atomic structure with the Bagaryatskii orientation relationship was established,and stepwise relaxation of the conjugate gradient energy minimization and constant-temperature and constant-pressure relaxation were performed under NPT(the isothermal–isobaric)*** mechanical property curves of theα-Fe/Fe3C models were obtained under different cementite terminal plane structures,and the evolution of the atomic structure was analyzed in *** addition,the influence of different hydrogen concentrations,different temperatures,different strain rates,changes in voids,and different micro-degrees of freedom on the deformation and failure mechanism of the model was investigated,aiming to provide a reliable way to explore the micro-mechanism of macro-cracking behavior of pipeline steel.

关键词： Ferrite-cementite lamellar structure Pipeline steel Failure mechanism Crack propagation Molecular dynamics

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High-frequency magnetic properties of biphase Ce_(2)Fe_(17)N_(3)/α-Fe microflakes with easy-plane anisotropy

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Journal of Rare Earths 2024年第1期42卷 110-115,I0004页

作者： Ke Wang Hang Zhang Yuandong Huang Zhibiao xu Fashen Li tao Wang Key Laboratory for Magnetism and Magnetic Materials of MOE Lanzhou UniversityLanzhou730000China Key Laboratory of Special Function Materials and Structure Design Ministry of EducationLanzhou UniversityLanzhou730000China

Soft magnetic composites(SMCs)are effective as magnetic powder cores in an *** to high saturation magnetization,large magnetocrystalline anisotropy and high operating frequency of M(metal)-RE(rear earth)soft magnetic composites,it is possible to miniaturize inductor cores by reducing total loss,especially eddy current loss and excess loss at high *** this article,the characteristics of Ce_(2)Fe_(17)N_(3)/α-Fe(CFN/F)loss per volume and effective permeability reaching a high frequency of 3 MHz are *** biphase CFN/F composite exhibits a high permeability of 16 at 70 MHz,which is two times greater than that of pure Ce_(2)Fe_(17)N_(3)(CFN)*** total loss is as low as 545 mW/cm^(3)at 3 MHz and 6 *** direct current(DC)-bias properties have a percent of permeability exceeding 65% at H=7960 A/*** phenomenon indicates that our material has a higher working frequency and lower core loss than other materials;the biphase CFN/F structure is a promising and efficient approach for developing the miniaturized radio frequency(RF)inductor core.

关键词： High frequency Soft magnetic composites Easy-plane anisotropy Permeability spectra Core loss Rare earths

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Adaptive detection of range-spread targets in homogeneous and partially homogeneous clutter plus subspace interference

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Journal of Systems Engineering and Electronics 2024年第1期35卷 43-54页

作者： JIAN tao HE Jia WANG Bencai LIU Yu xu Congan XIE Zikeng Research Institute of Information Fusion Naval Aviation UniversityYantai 264001China Air Force Early Warning Academy Wuhan 430019China

Adaptive detection of range-spread targets is considered in the presence of subspace interference plus Gaussian clutter with unknown covariance *** target signal and interference are supposed to lie in two linearly independent subspaces with deterministic but unknown *** on the two-step criteria,two adaptive detectors based on Gradient tests are proposed,in homogeneous and partially homogeneous clutter plus subspace interference,*** of the proposed detectors exhibit theoretically constant false alarm rate property against unknown clutter covariance matrix as well as the power *** results show that,the proposed detectors have better performance than their existing counterparts,especially for mismatches in the signal steering vectors.

关键词： adaptive detection subspace interference constant false alarm rate Gradient test partially homogeneous environment

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A Two-Layer Encoding Learning Swarm Optimizer Based on Frequent Itemsets for Sparse Large-Scale Multi-Objective Optimization

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IEEE/CAA Journal of Automatica Sinica 2024年第6期11卷 1342-1357页

作者： Sheng Qi Rui Wang tao Zhang xu Yang Ruiqing Sun Ling Wang College of Systems Engineering National University of Defense TechnologyChangsha 410073China Xiangjiang Laboratory Changsha 410205China College of Computer National University of Defense TechnologyChangsha 410073China Department of Automation Tsinghua UniversityBeijing 100084China IEEE

Traditional large-scale multi-objective optimization algorithms(LSMOEAs)encounter difficulties when dealing with sparse large-scale multi-objective optimization problems(SLM-OPs)where most decision variables are *** a result,many algorithms use a two-layer encoding approach to optimize binary variable Mask and real variable Dec ***,existing optimizers often focus on locating non-zero variable posi-tions to optimize the binary variables ***,approxi-mating the sparse distribution of real Pareto optimal solutions does not necessarily mean that the objective function is *** data mining,it is common to mine frequent itemsets appear-ing together in a dataset to reveal the correlation between *** by this,we propose a novel two-layer encoding learning swarm optimizer based on frequent itemsets(TELSO)to address these *** mined the frequent terms of multiple particles with better target values to find mask combinations that can obtain better objective values for fast ***-mental results on five real-world problems and eight benchmark sets demonstrate that TELSO outperforms existing state-of-the-art sparse large-scale multi-objective evolutionary algorithms(SLMOEAs)in terms of performance and convergence speed.

关键词： Evolutionary algorithms learning swarm optimiza-tion sparse large-scale optimization sparse large-scale multi-objec-tive problems two-layer encoding.

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Implementation of gastrointestinal function protection in severe acute pancreatitis

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Hepatobiliary & Pancreatic Diseases International 2024年第5期23卷 521-522页

作者： Fu-zheng tao Rong-Lin Jiang Shui-Fang Jin Intensive Care Unit Taizhou Integrated Traditional Chinese and Western Medicine HospitalTaizhou 310075China Intensive Care Unit the First Affiliated Hospital of Zhejiang Chinese Medical University(Zhejiang Provincial Hospital of Chinese Medicine)Hangzhou 310006China

Severe acute pancreatitis(SAP)is a serious systemic disease associated with strong local inflammatory reactions and serious systemic pathophysiological disorders caused by trypsin *** with SAP are prone to exhibit gastrointestinal ***,gastrointestinal dysfunction further aggravates the systemic inflammatory response and metabolic abnormalities,resulting in a more critical condition of *** dysfunction is considered to be the“trigger”of multiple organ dysfunction syndrome[1].Thus,it is important to maintain gastrointestinal homeostasis in the treatment of SAP.

关键词： gastrointestinal pancreatitis acute

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