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China's Energy Consumption Forecasting by GMDH Based Auto-Regressive Model

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Journal of Systems Science & Complexity 2017年第6期30卷 1332-1349页

作者： XIE Ling xiao jin HU Yi ZHAO Hengjun xiao Yi Business School Sichuan University School of Economics and Management University of Chinese Academy of Sciences School of Economics and Management Sichuan Radio and TV University School of Information Management Central China Normal University

It is very significant for us to predict future energy consumption accurately. As for China's energy consumption annual time series, the sample size is relatively small. This paper combines the traditional auto-regressive model with group method of data handling(GMDH) suitable for small sample prediction, and proposes a novel GMDH based auto-regressive(GAR) model. This model can finish the modeling process in self-organized manner, including finding the optimal complexity model, determining the optimal auto-regressive order and estimating model parameters. Further, four different external criteria are proposed and the corresponding four GAR models are constructed. The authors conduct empirical analysis on three energy consumption time series, including the total energy consumption, the total petroleum consumption and the total gas consumption. The results show that AS-GAR model has the best forecasting performance among the four GAR models, and it outperforms ARIMA model, BP neural network model, support vector regression model and GM(1, 1) ***, the authors give the out of sample prediction of China's energy consumption from 2014 to 2020 by AS-GAR model.

关键词： Auto-regressive model energy demand prediction GMDH small sample forecasting

Enhancement of motor functional recovery in thoracic spinal cord injury: voluntary wheel running versus forced treadmill exercise

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Neural Regeneration Research 2025年第3期20卷 836-844页

作者： Do-Hun Lee Dan Cao Younghye Moon Chen Chen Nai-Kui Liu xiao-ming Xu Wei Wu Spinal Cord and Brain Injury Research Group Stark Neurosciences Research InstituteIndiana University School of MedicineIndianapolisINUSA Department of Neurological Surgery Indiana University School of MedicineIndianapolisINUSA Department of Neuroscience Baylor College of MedicineHoustonTXUSA

Spinal cord injury necessitates effective rehabilitation strategies, with exercise therapies showing promise in promoting recovery. This study investigated the impact of rehabilitation exercise on functional recovery and morphological changes following thoracic contusive spinal cord injury. After a 7-day recovery period after spinal cord injury, mice were assigned to either a trained group(10 weeks of voluntary running wheel or forced treadmill exercise) or an untrained group. Bi-weekly assessments revealed that the exercise-trained group, particularly the voluntary wheel exercise subgroup, displayed significantly improved locomotor recovery, more plasticity of dopaminergic and serotonin modulation compared with the untrained group. Additionally, exercise interventions led to gait pattern restoration and enhanced transcranial magnetic motor-evoked potentials. Despite consistent injury areas across groups, exercise training promoted terminal innervation of descending axons. In summary, voluntary wheel exercise shows promise for enhancing outcomes after thoracic contusive spinal cord injury, emphasizing the role of exercise modality in promoting recovery and morphological changes in spinal cord injuries. Our findings will influence future strategies for rehabilitation exercises, restoring functional movement after spinal cord injury.

关键词： behavioral assessment motor function neural plasticity running wheel exercise spinal cord injury treadmill exercise voluntary exercise

Joint Monitoring of Ground and Sky for Cereal Crops Based on Scatterometer Measurement and ASAR Images

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Journal of Electronic Science and Technology 2019年第3期17卷 278-288页

作者： Lei He Feng-jin xiao the School of Software Engineering Chengdu University of Information TechnologyChengdu 610225 National Climate Center Beijing 100081

The joint monitoring of the ground and sky for cereal crops based on microwave data has become a popular method for researches on earth surface objects. Focused on the sensitivity of backscatter from the scatterometer measurement and advanced synthetic aperture radar (ASAR) images to cereal parameters of rice, nine acquisitions, including rice parameters related eco-physiological variables and scattering coefficients, have been carried over the paddy field corresponding to rice growth stages. This paper analyzes the relationship between the corresponding backscatter to the cereal parameters based on the measurement at the interesting bands, polarizations, and incidence angels. Further, a modified water cloud model is built based on the ground measurement and advanced integrated equation model (AIEM), and then cereal parameters from ASAR images are retrieved and verified. The research results show that the sensitivity of backscatter to cereals from the sensor of the radar scatterometer could be helpful to build the retrieve model for synthetic aperture radar (SAR) images, which can achieve the scientific goals of the joint monitoring of ground and sky for cereal crops.

关键词： Backscatter cereal joint monitoring scatterometer synthetic aperture radar(SAR)

Track dynamic behavior at rail welds at high speed

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Acta Mechanica Sinica 2010年第3期26卷 449-465页

作者： Guangwen xiao Xinbiao xiao Jun Guo Zefeng Wen Xuesong jin State Key Laboratory of Traction Power Southwest Jiaotong University 610031 Chengdu China

As a vehicle passing through a track with different weld irregularities, the dynamic performance of track com- ponents is investigated in detail by using a coupled vehi- cle-track model. In the model, the vehicle is modeled as a multi-body system with 35 degrees of freedom, and a Timoshenko beam is used to model the rails which are dis- cretely supported by sleepers. In the track model, the sleepers are modeled as rigid bodies accounting for their vertical, lat- eral and rolling motions and assumed to move backward at a constant speed to simulate the vehicle running along the track at the same speed. In the study of the coupled vehicle and track dynamics, the Hertizian contact theory and the theory proposed by Shen-Hedrick-Elkins are, respectively, used to calculate normal and creep forces between the wheel and the rails. In the calculation of the normal forces, the coefficient of the normal contact stiffness is determined by transient contact condition of the wheel and rail surface. In the calcu- lation of the creepages, the lateral, roll-over motions of the rail and the fact that the relative velocity between the wheel and rail in their common normal direction is equal to zero are simultaneously taken into account. The motion equations of the vehicle and track are solved by means of an explicit integration method, in which the rail weld irregularities are modeled as local track vertical deviations described by some ideal cosine functions. The effects of the train speed, the axle load, the wavelength and depth of the irregularities, and the weld center position in a sleeper span on the wheel-rail impact loading are analyzed. The numerical results obtained are greatly useful in the tolerance design of welded rail pro- file irregularity caused by hand-grinding after rail welding and track maintenances.

关键词： Rail weld. Irregularity. Vehicle-trackcouplingdynamics

Comparison of the carbon cycle and climate response to artificial ocean alkalinization and solar radiation modification

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Advances in Climate Change Research 2023年第2期14卷 322-334页

作者： xiao-Yu jin Long CAO Department of Atmospheric Sciences School of Earth SciencesZhejiang UniversityHangzhou 310058China

Carbon dioxide removal and solar radiation modification(SRM)are two classes of proposed climate intervention methods.A thorough understanding of climate system response to these methods calls for a good understanding of the carbon cycle *** this study,we used an Earth system model to examine the response of global climate and carbon cycle to artificial ocean alkalinization(AOA),a method of CO_(2)removal,and reduction in solar irradiance that represents the overall effect of solar radiation *** our simulations,AOA is applied uniformly over the global ice-free ocean under the RCP8.5 scenario to bring down atmospheric CO_(2)to the level of RCP4.5,and SRM is applied uniformly over the globe under the RCP8.5 scenario to bring down global mean surface temperature to the level of *** simulations show that with the same goal of temperature stabilization,AOA and SRM cause fundamentally different perturbations of the ocean and land carbon *** the end of the 21st century,relative to the simulation of RCP8.5,AOA-induced changes in ocean carbonate chemistry enhances global oceanic CO_(2)uptake by 983 PgC and increases global mean surface ocean pH by ***,AOA reduces land CO_(2)uptake by 79 PgC and reduces atmospheric CO_(2)concentration by 426×10^(−6).By contrast,relative to the simulation of RCP8.5,SRM has a minor effect on the oceanic CO_(2)uptake and ocean ***-induced cooling enhances land CO_(2)uptake by 140 PgC and reduces atmospheric CO_(2)concentration by 63×10^(−6).A sudden termination of SRM causes a rate of temperature change that is much larger than that of RCP8.5.A sudden termination of AOA causes a rate of temperature change that is comparable to that of RCP8.5 and a rate of ocean acidification that is much larger than that of RCP8.5.

关键词： Carbon dioxide removal Solar radiation modification Geoengineering Carbon cycle Ocean acidification

Modeling dual-scale epidemic dynamics on complex networks with reaction diffusion processes

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Journal of Zhejiang University-Science C(Computers and Electronics) 2014年第4期15卷 265-274页

作者： xiao-gang jin Yong miN AI Institute in College of Computer Science and Technology Zhejiang University College of Computer Science and Technology Zhejiang University of Technology

The frequent outbreak of severe foodborne diseases(e.g., haemolytic uraemic syndrome and Listeriosis) in 2011 warns of a potential threat that world trade could spread fatal pathogens(e.g., enterohemorrhagic Escherichia coli). The epidemic potential from trade involves both intra-proliferation and inter-diffusion. Here, we present a worldwide vegetable trade network and a stochastic computational model to simulate global trade-mediated epidemics by considering the weighted nodes and edges of the network and the dual-scale dynamics of epidemics. We address two basic issues of network structural impact in global epidemic patterns:(1) in contrast to the prediction of heterogeneous network models, the broad variability of node degree and edge weights of the vegetable trade network do not determine the threshold of global epidemics;(2) a ‘penetration effect', by which community structures do not restrict propagation at the global scale, quickly facilitates bridging the edges between communities, and leads to synchronized diffusion throughout the entire network. We have also defined an appropriate metric that combines dual-scale behavior and enables quantification of the critical role of bridging edges in disease diffusion from widespread trading. The unusual structure mechanisms of the trade network model may be useful in producing strategies for adaptive immunity and reducing international trade frictions.

关键词： Worldwide trade networks Foodbome diseases Scale-free networks Mean-field analysis

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Schatten-p Class(0

Acta Mathematica Sinica,English Series 2015年第4期31卷 703-714页

作者： Lian Hua xiao xiao Feng WANG jin XIA School of Mathematics and Information Science and Key Laboratory of Mathematics and Interdisciplinary Sciences of the Guangdong Higher Education Institute Guangzhou University

In this paper, we discuss the Schatten-p class （0 〈 p≤∞ ） of Toeplitz operators on generalized Foek space with the symbol in positive Borel measure. It makes a great difference from other papers by using the estimates of the kernel and the weight together instead of separately estimating each other. We also get the equivalent conditions when a Toeplitz operator is in the Schatten-p class.

关键词： Schatten class generalized Fock space compact operator

REAL-TIME FLOOD FORECASTING METHOD WITH 1-D UNSTEADY FLOW MODEL

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Journal of Hydrodynamics 2007年第2期19卷 150-154页

作者： MU jin-bin ZHANG xiao-feng State Key Laboratory of Water Resources and Hydropower Engineering Science Wuhan University Wuhan 430072China

A real-time forecasting method coupled with the I-D unsteady flow model with the recursive least-square method was developed. The 1-D unsteady flow model was modified by using the time-variant parameter and revising it dynamically through introducing a variable weighted forgetting factor, such that the output of the model could be adjusted for the real time forecasting of floods. The application of the new real time forecasting model in the reach from Yichang to Luoshan of the Yangtze River was demonstrated. Computational result shows that the forecasting accuracy of the new model is much higher than that of the original 1-D unsteady flow model. The method developed is effective for flood forecasting, and can be used for practical operation in the flood forecasting.

关键词： unsteady flow hydraulic model least squares,time variant forgetting factor real-time forecasting

Neottia wuyishanensis(Orchidaceae:Neottieae),a new species from Fujian,China

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Plant Diversity 2021年第5期43卷 426-431页

作者： Bing-Hua Chen xiao-Hua jin College of Life Sciences Fujian Normal UniversityFuzhou 350117China State Key Laboratory of Systematic and Evolutionary Botany and Herbarium Institute of BotanyChinese Academy of SciencesBeijing 100093China The Public Service Platform for Industrialization Development Technology of Marine Biological Medicine and Products of the State Oceanic Administration Fujian Key Laboratory of Special Marine Bioresource Sustainable UtilizationSouthern Institute of OceanographyCollege of Life SciencesFujian Normal UniversityFuzhou 350117China

A new species,Neottia wuyishanensis(Neottieae,Orchidaceae),is described and illustrated from Wuyishan,Fujian,eastern China,based on morphological characters and molecular *** phylogenetics indicate that *** is nested within the clade formed by Neottia fugongensis and Neottia ***,*** is similar to *** and ***,but differs from them by having indistinct auricles at the base,and in the shape and size of lobelets.

关键词： China Neottia wuyishanensis New species Orchidaceae