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Lie symmetry analysis and invariant solutions for the(3+1)-dimensional Virasoro integrable model
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作者 胡恒春 李雅琦 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第4期249-254,共6页
Lie symmetry analysis is applied to a(3+1)-dimensional Virasoro integrable model and the corresponding similarity reduction equations are obtained with the different infinitesimal generators.Invariant solutions with a... Lie symmetry analysis is applied to a(3+1)-dimensional Virasoro integrable model and the corresponding similarity reduction equations are obtained with the different infinitesimal generators.Invariant solutions with arbitrary functions for the(3+1)-dimensional Virasoro integrable model,including the interaction solution between a kink and a soliton,the lump-type solution and periodic solutions,have been studied analytically and graphically. 展开更多
关键词 (3+1)-dimensional Virasoro integrable model Lie symmetry invariant solutions
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Equivalent transformation between the matrices for expanding integrable model of the hierarchy of evolution equation
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作者 姚玉芹 陈登远 《Journal of Shanghai University(English Edition)》 CAS 2007年第3期255-258,共4页
A direct method for obtaining the expanding integrable models of the hierarchies of evolution equations was proposed. By using the equivalent transformation between the matrices, a new isospectral problem was directly... A direct method for obtaining the expanding integrable models of the hierarchies of evolution equations was proposed. By using the equivalent transformation between the matrices, a new isospectral problem was directly established according to the known isospectral problem, which can be used to obtain the expanding integrable model of the known hierarchy. 展开更多
关键词 isospectral problem expanding integrable model matrix.
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Regional Climate Damage Quantification and Its Impacts on Future Emission Pathways Using the RICE Model
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作者 Shili YANG Wenjie DONG +2 位作者 Jieming CHOU Yong ZHANG Weixing ZHAO 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2024年第9期1843-1852,共10页
This study quantified the regional damages resulting from temperature and sea level changes using the Regional Integrated of Climate and Economy(RICE)model,as well as the effects of enabling and disabling the climate ... This study quantified the regional damages resulting from temperature and sea level changes using the Regional Integrated of Climate and Economy(RICE)model,as well as the effects of enabling and disabling the climate impact module on future emission pathways.Results highlight varied damages depending on regional economic development and locations.Specifically,China and Africa could suffer the most serious comprehensive damages caused by temperature change and sea level rise,followed by India,other developing Asian countries(OthAsia),and other high-income countries(OHI).The comprehensive damage fractions for China and Africa are projected to be 15.1%and 12.5%of gross domestic product(GDP)in 2195,with corresponding cumulative damages of 124.0 trillion and 87.3 trillion United States dollars(USD)from 2005 to 2195,respectively.Meanwhile,the comprehensive damage fractions in Japan,Eurasia,and Russia are smaller and projected to be lower than 5.6%of GDP in 2195,with cumulative damages of 6.8 trillion,4.2 trillion,and 3.3 trillion USD,respectively.Additionally,coastal regions like Africa,the European Union(EU),and OHI show comparable damages for sea level rise and temperature change.In China,however,sea level-induced damages are projected to exceed those from temperature changes.Moreover,this study indicates that switching the damage modules on or off affects the regional and global emission trajectories,but the magnitude is relatively small.By 2195,global emissions under the experiments with all of the damage modules switched off,only the sea level damage module switched on,and only the temperature damage module switched on,were 3.5%,2.3%and 1.2%higher than those with all of the damage modules switched on,respectively. 展开更多
关键词 climate damage integrated assessment model carbon emissions sea level rise temperature change
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The Construction of Integrated Nursing Model Prevention of Oxaliplatin Chemotherapy-Induced Peripheral Nerve Injury
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作者 Qiong Wen Xiaomei Cai 《Journal of Biosciences and Medicines》 2024年第2期340-348,共9页
Objective: To investigate the effect of the integrated nursing model in the prevention of chemotherapy-induced peripheral injury. Methods: A total of 60 tumor patients receiving oxaliplatin for 1 - 6 cycles of chemoth... Objective: To investigate the effect of the integrated nursing model in the prevention of chemotherapy-induced peripheral injury. Methods: A total of 60 tumor patients receiving oxaliplatin for 1 - 6 cycles of chemotherapy from January to September 2023 were selected. 30 patients were selected from January to March and divided into the control group, and 30 patients were selected from July to 9 as the experimental group. The control group received conventional chemotherapy nursing, while the experimental group received integrated nursing. Anxiety, peripheral nerve toxicity stage and quality of life score were compared between the two groups before and after intervention. Results: After intervention, the scores of the self-rating Anxiety Scale (SAS) and the total scores of the oxaliplatin Levi specific sensory neurotoxicity scale in the experimental group were significantly lower than those in the control group, and the differences were statistically significant (P< 0.05);The Quality of Life Scale (FACT-G) score of cancer patients was higher than that of control group, and the difference was statistically significant (P< 0.05). Conclusion: The integrated nursing model can effectively reduce the anxiety of patients, reduce the incidence of peripheral nerve injury and improve the quality of life of patients. 展开更多
关键词 Integrated Nursing Intervention model CHEMOTHERAPY Peripheral Nerve Toxicity ANXIETY Quality of Life
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The Model of“Post,Course,Competition,Certificate”Integrated Education for Electronic Information Engineering Technology Major in Higher Vocational Colleges
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作者 Qinqin Jing Yun Liu Xinyu Zheng 《Journal of Contemporary Educational Research》 2024年第5期223-229,共7页
The core education function of higher vocational colleges is to train technical talents with high quality,so as to meet the needs of talents in the development stage of our society.Under the guidance of talent trainin... The core education function of higher vocational colleges is to train technical talents with high quality,so as to meet the needs of talents in the development stage of our society.Under the guidance of talent training,higher vocational colleges need to pay attention to establishing an all-round and three-dimensional education model,and promote innovation of higher vocational education on the basis of this.It is also a way to promote the innovation of higher vocational education to vigorously promote the construction of“post,course,competition,certificate”mode in the construction of education mode.Through the construction of“post,course,competition,certificate”mode,the education mode of higher vocational colleges is gradually improved,so as to strengthen the effectiveness of talent training in higher vocational colleges.Therefore,in this paper,the author puts forward some suggestions to promote the construction of the integrated education mode of the electronic information engineering technology major in higher vocational colleges,so as to help improve the talent training level of higher vocational colleges. 展开更多
关键词 Higher vocational education Electronic information engineering technology major “Post course competition certificate” Integrated education model
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Analysis of the Effect of Integrated Extended Care Model in Improving the Quality of Life of Elderly Patients with Type 2 Diabetes Mellitus
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作者 Lili Liu 《Journal of Clinical and Nursing Research》 2024年第4期174-179,共6页
Objective: To analyze the impact of an integrated extended care model on improving the quality of life of elderly patients with Type 2 Diabetes Mellitus (T2DM). Methods: A total of 176 patients admitted to the hospita... Objective: To analyze the impact of an integrated extended care model on improving the quality of life of elderly patients with Type 2 Diabetes Mellitus (T2DM). Methods: A total of 176 patients admitted to the hospital from March 2015 to February 2018 were selected and randomly assigned to an observation group and a control group, with 88 patients each. The control group implemented conventional nursing interventions, and the observation group carried out an integrated extended-care model. The level of glycemic control, quality of life, and daily medication adherence between both groups were compared. Results: The observation group showed significant improvement in the level of glycemic control, and their fasting blood glucose, 2-hour postprandial blood glucose, and glycated hemoglobin levels were significantly lower as compared with those in the study group (P < 0.05). The quality of life of the patients in the observation group was higher than that of the control group (P < 0.05). The observation group had a higher compliance score (95.48 ± 7.45) than the control group (81.31 ± 8.72) (t = 8.909, P < 0.05). Conclusion: The integrated extended care model allows patients to receive comprehensive and individualized nursing services after discharge, which improves the effect of drug therapy and the quality of life of patients. 展开更多
关键词 Integrated extended care model Elderly type 2 diabetes mellitus Quality of life
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Deep Learning-Based Stock Price Prediction Using LSTM Model
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作者 Jiayi Mao Zhiyong Wang 《Proceedings of Business and Economic Studies》 2024年第5期176-185,共10页
The stock market is a vital component of the broader financial system,with its dynamics closely linked to economic growth.The challenges associated with analyzing and forecasting stock prices have persisted since the ... The stock market is a vital component of the broader financial system,with its dynamics closely linked to economic growth.The challenges associated with analyzing and forecasting stock prices have persisted since the inception of financial markets.By examining historical transaction data,latent opportunities for profit can be uncovered,providing valuable insights for both institutional and individual investors to make more informed decisions.This study focuses on analyzing historical transaction data from four banks to predict closing price trends.Various models,including decision trees,random forests,and Long Short-Term Memory(LSTM)networks,are employed to forecast stock price movements.Historical stock transaction data serves as the input for training these models,which are then used to predict upward or downward stock price trends.The study’s empirical results indicate that these methods are effective to a degree in predicting stock price movements.The LSTM-based deep neural network model,in particular,demonstrates a commendable level of predictive accuracy.This conclusion is reached following a thorough evaluation of model performance,highlighting the potential of LSTM models in stock market forecasting.The findings offer significant implications for advancing financial forecasting approaches,thereby improving the decision-making capabilities of investors and financial institutions. 展开更多
关键词 Autoregressive integrated moving average(ARIMA)model Long Short-Term Memory(LSTM)network Forecasting Stock market
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AN INTEGRABLE HIERARCHY AND ITS EXPANDING LAX INTEGRABLE MODEL 被引量:1
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作者 张玉峰 闫庆友 许曰才 《Annals of Differential Equations》 2004年第4期423-428,共6页
In general, Liouville integrable hierarchies of evolution equations were obtained by choosing proper U in zero curvature frame Ut - Vx + [U, V] = 0 first. But in the present paper, a new Liouville integrable hierarchy... In general, Liouville integrable hierarchies of evolution equations were obtained by choosing proper U in zero curvature frame Ut - Vx + [U, V] = 0 first. But in the present paper, a new Liouville integrable hierarchy possessing bi-Hamiltonian structure is obtained by choosing V with derivatives in x and spectral potentials. Then integrable coupling, i.e. expanding Lax integrable model of the hierarchy obtained is presented by constructing a subalgebra of loop algebra A2. 展开更多
关键词 integrable hierarchy expanding integrable model loop algebra
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DIAGONAL BOUNDARY K-MATRICES FOR TWOINTEGRABLE NINETEEN-VERTEX MODELS
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作者 管习文 杨善德 王美山 《Acta Mathematica Scientia》 SCIE CSCD 1999年第3期356-360,共5页
Using Sklyanin's formalism, the authors study two integrable nineteen-vertex models with open boundary conditions(BC). By solving reflection equation(RE), three different diagonal boundary K matrices for each mode... Using Sklyanin's formalism, the authors study two integrable nineteen-vertex models with open boundary conditions(BC). By solving reflection equation(RE), three different diagonal boundary K matrices for each model are obtained and the corresponding explicit forms of the Hamiltonians with three different kinds of nontrival boundary terms are given. 展开更多
关键词 Sklyanin's-formalism integrable model boundary K matrix
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Deformation and (3 + 1)-dimensional integrable model
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作者 俞军 楼森岳 《Science China Mathematics》 SCIE 2000年第6期655-660,共6页
A suitable and effective deformation relation is derived by using the Miura transformation. In the light of this relation, the (2 + 1)-dimensional linear heat conductive equation is deformed to a (3 + 1)-dimensional m... A suitable and effective deformation relation is derived by using the Miura transformation. In the light of this relation, the (2 + 1)-dimensional linear heat conductive equation is deformed to a (3 + 1)-dimensional model. It is proved by standard singularity structure analysis that the (3+1)-dimensional nonlinear equation obtained here is Painlevé integrable. 展开更多
关键词 DEFORMATION Painlevé analysis integrable model
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Dynamic stability analysis of porous functionally graded beams under hygro-thermal loading using nonlocal strain gradient integral model 被引量:2
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作者 Pei ZHANG P.SCHIAVONE Hai QING 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2023年第12期2071-2092,共22页
We present a study on the dynamic stability of porous functionally graded(PFG)beams under hygro-thermal loading.The variations of the properties of the beams across the beam thicknesses are described by the power-law ... We present a study on the dynamic stability of porous functionally graded(PFG)beams under hygro-thermal loading.The variations of the properties of the beams across the beam thicknesses are described by the power-law model.Unlike most studies on this topic,we consider both the bending deformation of the beams and the hygro-thermal load as size-dependent,simultaneously,by adopting the equivalent differential forms of the well-posed nonlocal strain gradient integral theory(NSGIT)which are strictly equipped with a set of constitutive boundary conditions(CBCs),and through which both the stiffness-hardening and stiffness-softening effects of the structures can be observed with the length-scale parameters changed.All the variables presented in the differential problem formulation are discretized.The numerical solution of the dynamic instability region(DIR)of various bounded beams is then developed via the generalized differential quadrature method(GDQM).After verifying the present formulation and results,we examine the effects of different parameters such as the nonlocal/gradient length-scale parameters,the static force factor,the functionally graded(FG)parameter,and the porosity parameter on the DIR.Furthermore,the influence of considering the size-dependent hygro-thermal load is also presented. 展开更多
关键词 nonlocal strain gradient integral model dynamic stability porous functionally graded(PFG)shear deformation beam size-dependent hygro-thermal load generalized differential quadrature method(GDQM)
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An anomaly detection method for spacecraft solar arrays based on the ILS-SVM model 被引量:2
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作者 WANG Yu ZHANG Tao +1 位作者 HUI Jianjiang LIU Yajie 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2023年第2期515-529,共15页
Solar arrays are important and indispensable parts of spacecraft and provide energy support for spacecraft to operate in orbit and complete on-orbit missions.When a spacecraft is in orbit,because the solar array is ex... Solar arrays are important and indispensable parts of spacecraft and provide energy support for spacecraft to operate in orbit and complete on-orbit missions.When a spacecraft is in orbit,because the solar array is exposed to the harsh space environment,with increasing working time,the performance of its internal electronic components gradually degrade until abnormal damage occurs.This damage makes solar array power generation unable to fully meet the energy demand of a spacecraft.Therefore,timely and accurate detection of solar array anomalies is of great significance for the on-orbit operation and maintenance management of spacecraft.In this paper,we propose an anomaly detection method for spacecraft solar arrays based on the integrated least squares support vector machine(ILS-SVM)model:it selects correlated telemetry data from spacecraft solar arrays to form a training set and extracts n groups of training subsets from this set,then gets n corresponding least squares support vector machine(LS-SVM)submodels by training on these training subsets,respectively;after that,the ILS-SVM model is obtained by integrating these submodels through a weighting operation to increase the prediction accuracy and so on;finally,based on the obtained ILS-SVM model,a parameterfree and unsupervised anomaly determination method is proposed to detect the health status of solar arrays.We use the telemetry data set from a satellite in orbit to carry out experimental verification and find that the proposed method can diagnose solar array anomalies in time and can capture the signs before a solar array anomaly occurs,which reflects the applicability of the method. 展开更多
关键词 spacecraft solar array anomaly detection integrated least squares support vector machine(ILS-SVM) induced ordered weighted average(IOWA)operator integrated model
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Evaluation of the water conservation function in the Ili River Delta of Central Asia based on the InVEST model 被引量:2
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作者 CAO Yijie MA Yonggang +2 位作者 BAO Anming CHANG Cun LIU Tie 《Journal of Arid Land》 SCIE CSCD 2023年第12期1455-1473,共19页
The Ili River Delta(IRD)is an ecological security barrier for the Lake Balkhash and an important water conservation area in Central Asia.In this study,we selected the IRD as a typical research area,and simulated the w... The Ili River Delta(IRD)is an ecological security barrier for the Lake Balkhash and an important water conservation area in Central Asia.In this study,we selected the IRD as a typical research area,and simulated the water yield and water conservation from 1975 to 2020 using the water yield module of the Integrated Valuation of Ecosystem Services and Tradeoffs(InVEST)model.We further analyzed the temporal and spatial variations in the water yield and water conservation in the IRD from 1975 to 2020,and investigated the main driving factors(precipitation,potential evapotranspiration,land use/land cover change,and inflow from the Ili River)of the water conservation variation based on the linear regression,piecewise linear regression,and Pearson's correlation coefficient analyses.The results indicated that from 1975 to 2020,the water yield and water conservation in the IRD showed a decreasing trend,and the spatial distribution pattern was"high in the east and low in the west";overall,the water conservation of all land use types decreased slightly.The water conservation volume of grassland was the most reduced,although the area of grassland increased owing to the increased inflow from the Ili River.At the same time,the increased inflow has led to the expansion of wetland areas,the improvement of vegetation growth,and the increase of regional evapotranspiration,thus resulting in an overall reduction in the water conservation.The water conservation depth and precipitation had similar spatial distribution patterns;the change in climate factors was the main reason for the decline in the water conservation function in the delta.The reservoir in the upper reaches of the IRD regulated runoff into the Lake Balkhash,promoted vegetation restoration,and had a positive effect on the water conservation;however,this positive effect cannot offset the negative effect of enhanced evapotranspiration.These results provide a reference for the rational allocation of water resources and ecosystem protection in the IRD. 展开更多
关键词 water conservation function water yield Integrated Valuation of Ecosystem Services and Tradeoffs(InVEST)model climate change land use/land cover change(LUCC) Ili River Delta Lake Balkhash
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Integrating Downstream Ecological, Social and Economic Effects of Hydropower to Hydraulic Modeling: A Review
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作者 J. Bastian Höller Anders G. Andersson J. Gunnar I. Hellström 《World Journal of Mechanics》 2023年第8期149-172,共24页
Hydropower gains increasing importance as a steerable and controllable power source in a renewable energy mix and deregulated markets. Although hydropower produces fossil-free energy, it has a significant impact on th... Hydropower gains increasing importance as a steerable and controllable power source in a renewable energy mix and deregulated markets. Although hydropower produces fossil-free energy, it has a significant impact on the local environment. This review investigates the effects of flow alterations by hydropower on the downstream river system and the possibilities to integrate these effects into hydraulic modeling. The results show that various effects of flow regulation on the ecosystem, but also social and economic effects on related communities were observed in the last decades. The application of hydraulic models for investigations of ecological effects is common. Especially hydraulic effects and effects on fish were extensively modeled with the help of hydraulic 1D- and 2D-simulations. Current applications to investigate social and economic effects integrated into hydraulic modeling are meanwhile limited. Approaches to realizing this integration are presented. Further research on the economic valuation of ecosystems and integration of social and economic effects to hydraulic models is necessary to develop holistic tools to support decision-making on sustainable hydropower. 展开更多
关键词 Sustainable Hydropower Hydraulic Simulation River Regulation Down-stream Effects Integrated modeling
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SIMULATION OF THE PHYSIOLOGICAL RESPONSES OF C 3 PLANT LEAVES TO ENVIRONMENTAL FACTORS BY A MODEL WHICH COMBINES STOMATAL CONDUCTANCE, PHOTOSYNTHESIS AND TRANSPIRATION 被引量:41
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作者 于强 王天铎 《Acta Botanica Sinica》 CSCD 1998年第8期740-754,共15页
Transpiration element is included in the integrated stomatal conductance photosynthesis model by considering gaseous transfer processes, so the present model is capable to simulate the influence of boundary layer con... Transpiration element is included in the integrated stomatal conductance photosynthesis model by considering gaseous transfer processes, so the present model is capable to simulate the influence of boundary layer conductance. Leuning in his revised Ball's model replaced relative humidity with VPD s (the vapor pressure deficit from stomatal pore to leaf surface) and thereby made the relation with transpiration more straightforward, and made it possible for the regulation of transpiration and the influence of boundary layer conductance to be integrated into the combined model. If the differences in water vapor and CO 2 concentration between leaf and ambient air are considered, VPD s , the evaporative demand, is influenced by stomatal and boundary layer conductance. The physiological responses of photosynthesis, transpiration, and stomatal function, and the changes of intercellular CO 2 and water use efficiency to environmental factors, such as wind speed, photon flux density, leaf temperature and ambient CO 2, are analyzed. It is shown that if the boundary layer conductance drops to a level comparable with stomatal conductance, the results of simulation by the model presented here differ significantly from those by the previous model, and, in some cases, are more realistic than the latter. 展开更多
关键词 PHOTOSYNTHESIS TRANSPIRATION Stomatal conductance Boundary layer conductance Integrated model
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Nested Bethe Ansatz for Spin Ladder Model with Open Boundary Conditions 被引量:2
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作者 WUJun-Fang ZHANGChun-Min +1 位作者 YUERui-Hong LIRun-Ling 《Communications in Theoretical Physics》 SCIE CAS CSCD 2005年第4期687-694,共8页
The nested Bethe ansatz (BA) method is applied to find the eigenvalues and the eigenvectors of the transfer matrix for spin-ladder model with open boundary conditions. Based on the reflection equation, we find the gen... The nested Bethe ansatz (BA) method is applied to find the eigenvalues and the eigenvectors of the transfer matrix for spin-ladder model with open boundary conditions. Based on the reflection equation, we find the general diagonal solution, which determines the generalboundary interaction in the Hamiltonian. We introduce the spin-ladder model with open boundary conditions. By finding the solution K± of the reflection equation which determines the nontrivial boundary terms in the Hamiltonian, we diagonalize the transfer matrix of the spin-ladder model with open boundary conditions in the framework of nested BA. 展开更多
关键词 integrable model coordinate bethe ansatz quantum inverse scattering method bethe ansatz equation nested bethe ansatz
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Integrated analysis of plasma rotation effect on HL-3 hybrid scenario
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作者 薛淼 郑国尧 +5 位作者 薛雷 李佳鲜 王硕 杜海龙 朱毅仁 周月 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第8期329-336,共8页
The hybrid scenario,which has good confinement and moderate MHD instabilities,is a proposed operation scenario for international thermonuclear experimental reactor(ITER).In this work,the effect of plasma rotation on t... The hybrid scenario,which has good confinement and moderate MHD instabilities,is a proposed operation scenario for international thermonuclear experimental reactor(ITER).In this work,the effect of plasma rotation on the HL-3 hybrid scenario is analyzed with the integrated modeling framework OMFIT.The results show that toroidal rotation has no obvious effect on confinement with a high line averaged density of n_(bar)~(7)×10^(19)m^(-3).In this case,the ion temperature only changes from 4.7 keV to 4.4 keV with the rotation decreasing from 10^(5) rad/s to 10^(3) rad/s,which means that the turbulent heat transport is not dominant.While in the scenarios characterized by lower densities,such as n_(bar)~4×10^(19)m^(-3),turbulent transport becomes dominant in determining heat transport.The ion temperature rises from 3.8 keV to 6.1 keV in the core as the rotation velocity increases from 10^(3) rad/s to 10^(5) rad/s.Despite the ion temperature rising,the rotation velocity does not obviously affect electron temperature or density.Additionally,it is noteworthy that the variation in rotation velocity does not significantly affect the global confinement of plasma in scenarios with low density or with high density. 展开更多
关键词 HL-3 hybrid scenario toroidal rotation integrated modeling
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Influencing Factors and Prediction of Risk of Returning to Ecological Poverty in Liupan Mountain Region,China
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作者 CUI Yunxia LIU Xiaopeng +2 位作者 JIANG Chunmei TIAN Rujun NIU Qingrui 《Chinese Geographical Science》 SCIE CSCD 2024年第3期420-435,共16页
China has resolved its overall regional poverty in 2020 by attaining moderate societal prosperity.The country has entered a new development stage designed to achieve its second centenary goal.However,ecological fragil... China has resolved its overall regional poverty in 2020 by attaining moderate societal prosperity.The country has entered a new development stage designed to achieve its second centenary goal.However,ecological fragility and risk susceptibility have increased the risk of returning to ecological poverty.In this paper,the Liupan Mountain Region of China was used as a case study,and the counties were used as the scale to reveal the spatiotempora differentiation and influcing factors of the risk of returning to poverty in study area.The indicator data for returning to ecological poverty from 2011-2020 were collected and summarized in three dimensions:ecological,economic and social.The autoregressive integrated moving average model(ARIMA)time series and exponential smoothing method(ES)were used to predict the multidimensional indicators of returning to ecological poverty for 61 counties(districts)in the Liupan Mountain Region for 2021-2030.The back propagation neural network(BPNN)and geographic information system(GIS)were used to generate the spatial distribution and time variation for the index of the risk of returning to ecological poverty(RREP index).The results show that 1)ecological factors were the main factors in the risk of returning to ecological poverty in Liupan Mountain Region.2)The RREP index for the 61 counties(districts)exhibited a downward trend from 2021-2030.The RREP index declined more in medium-and high-risk areas than in low-risk areas.From 2021 to 2025,the RREP index exhibited a slight downward trend.From 2026 to2030,the RREP index was expected to decline faster,especially from 2029-2030.3)Based on the RREP index,it can be roughly divided into three types,namely,the high-risk areas,the medium-risk areas,and the low-risk areas.The natural resource conditions in lowrisk areas of returning to ecological poverty,were better than those in medium-and high-risk areas. 展开更多
关键词 risk of returning to ecological poverty autoregressive integrated moving average model(ARIMA) exponential smoothing model back propagation neural network(BPNN) Liupan Mountain Region China
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Quantifying Contribution of Recycled Moisture to Precipitation in Temperate Glacier Region,Southeastern Tibetan Plateau,China
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作者 MA Yanwei PU Tao +2 位作者 SHI Xiaoyi MA Xinggang YU Hongmei 《Chinese Geographical Science》 SCIE CSCD 2024年第4期764-776,共13页
Recycled moisture is an important indicator of the renewal capacity of regional water resources.Due to the existence of Yulong Snow Mountain,Lijiang in Yunnan Province,southeast of the Qinghai-Tibet Plateau,China,is t... Recycled moisture is an important indicator of the renewal capacity of regional water resources.Due to the existence of Yulong Snow Mountain,Lijiang in Yunnan Province,southeast of the Qinghai-Tibet Plateau,China,is the closest ocean glacier area to the equator in Eurasia.Daily precipitation samples were collected from 2017 to 2018 in Lijiang to quantify the effect of sub-cloud evaporation and recycled moisture on precipitation combined with the d-excess model during monsoon and non-monsoon periods.The results indicated that the d-excess values of precipitation fluctuated between–35.6‰and 16.0‰,with an arithmetic mean of 3.5‰.The local meteoric water line(LMWL)wasδD=7.91δ^(18)O+2.50,with a slope slightly lower than the global meteoric water line(GMWL).Subcloud evaporation was higher during the non-monsoon season than during the monsoon season.It tended to peak in March and was primarily influenced by the relative humidity.The source of the water vapour affected the proportion of recycled moisture.According to the results of the Hybrid Single-Particle Lagrangian Integrated Trajectory(HYSPLIT)model,the main sources of water vapour in Lijiang area during the monsoon period were the southwest and southeast monsoons.During the non-monsoon period,water vapour was transported by a southwesterly flow.The recycled moisture in Lijiang area between March and October 2017 was 10.62%.Large variations were observed between the monsoon and non-monsoon seasons,with values of 5.48%and 25.65%,respectively.These differences were primarily attributed to variations in the advection of water vapour.The recycled moisture has played a supplementary role in the precipitation of Lijiang area. 展开更多
关键词 recycled moisture stable isotope PRECIPITATION d-excess Hybrid Single-Particle Lagrangian Integrated Trajectory(HYSPLIT)model southeastern Tibetan Plateau China
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Oxygen and hydrogen isotope characteristics of different water bodies in the Burqin River Basin of the Altay Mountains,China
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作者 XIE Yida WANG Feiteng LIU Shuangshuang 《Journal of Arid Land》 SCIE CSCD 2024年第10期1365-1379,共15页
Characterization of the spatial and temporal variability of stable isotopes in surface water is essential for interpreting hydrological processes.In this study,we collected the water samples of river water,groundwater... Characterization of the spatial and temporal variability of stable isotopes in surface water is essential for interpreting hydrological processes.In this study,we collected the water samples of river water,groundwater,and reservoir water in the Burqin River Basin of the Altay Mountains,China in 2021,and characterized the oxygen and hydrogen isotope variations in different water bodies via instrumental analytics and modeling.Results showed significant seasonal variations in stable isotope ratios of oxygen and hydrogen(δ18O andδ2H,respectively)and significant differences inδ18O andδ2H among different water bodies.Higherδ18O andδ2H values were mainly found in river water,while groundwater and reservoir water had lower isotope ratios.River water and groundwater showed differentδ18O-δ2H relationships with the local meteoric water line,implying that river water and groundwater are controlled by evaporative enrichment and multi-source recharge processes.The evaporative enrichment experienced by reservoir water was less significant and largely influenced by topography,recharge sources,local moisture cycling,and anthropogenic factors.Higher deuterium excess(d-excess)value of 14.34‰for river water probably represented the isotopic signature of combined contributions from direct precipitation,snow and glacial meltwater,and groundwater recharge.The average annual d-excess values of groundwater(10.60‰)and reservoir water(11.49‰)were similar to the value of global precipitation(10.00‰).The findings contribute to understanding the hydroclimatic information reflected in the month-by-month variations in stable isotopes in different water bodies and provide a reference for the study of hydrological processes and climate change in the Altay Mountains,China. 展开更多
关键词 water bodies stable isotopes deuterium excess(d-excess) Hybrid Single-Particle Lagrangian Integrated Trajectory(HYSPLIT)model Burqin River Basin Altay Mountains
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