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A 2D equivalent linear model for seismic response analysis of a layered transversely isotropic half-space
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作者 Liang Jianwen Zhang Ping Ba Zhenning 《Earthquake Engineering and Engineering Vibration》 2025年第2期311-332,共22页
Natural soil generally exhibits significant transverse isotropy(TI)due to weathering and sedimentation,meaning that horizontal moduli differ from their vertical counterpart.The TI mechanical model is more appropriate ... Natural soil generally exhibits significant transverse isotropy(TI)due to weathering and sedimentation,meaning that horizontal moduli differ from their vertical counterpart.The TI mechanical model is more appropriate for actual situations.Although soil exhibits material nonlinearity under earthquake excitation,existing research on the TI medium is limited to soil linearity and neglects the nonlinear response of TI sites.A 2D equivalent linear model for a layered TI half-space subjected to seismic waves is derived in the transformed wave number domain using the exact dynamic stiffness matrix of the TI medium.This study introduces a method for determining the effective shear strain of TI sites under oblique wave incidence,and further describes a systematic study on the effects of TI parameters and soil nonlinearity on site responses.Numerical results indicate that seismic responses of the TI medium significantly differ from those of isotropic sites and that the responses are highly dependent on TI parameters,particularly in nonlinear cases,while also being sensitive to incident angle and excitation intensity.Moreover,the differences in peak acceleration and waveform for various TI materials may also be amplified due to the strong nonlinearity.The study provides valuable insights for improving the accuracy of seismic response analysis in engineering applications. 展开更多
关键词 layered transversely isotropic half-space soil nonlinearity TI site response analysis stiffness matrix method equivalent linear model
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Optimized Lagged Multiple Linear Regression Model for MJO Prediction:Considering the Surface and Subsurface Oceanic Processes over the Maritime Continent
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作者 LU Kecheng LI Yiran +1 位作者 HU Haibo WANG Ziyi 《Journal of Ocean University of China》 2025年第4期840-850,共11页
The Madden-Julian Oscillation(MJO)is a key atmospheric component connecting global weather and climate.It func-tions as a primary source for subseasonal forecasts.Previous studies have highlighted the vital impact of ... The Madden-Julian Oscillation(MJO)is a key atmospheric component connecting global weather and climate.It func-tions as a primary source for subseasonal forecasts.Previous studies have highlighted the vital impact of oceanic processes on MJO propagation.However,few existing MJO prediction approaches adequately consider these factors.This study determines the critical region for the oceanic processes affecting MJO propagation by utilizing 22-year Climate Forecast System Reanalysis data.By intro-ducing surface and subsurface oceanic temperature within this critical region into a lagged multiple linear regression model,the MJO forecasting skill is considerably optimized.This optimization leads to a 12 h enhancement in the forecasting skill of the first principal component and efficiently decreases prediction errors for the total predictions.Further analysis suggests that,during the years in which MJO events propagate across the Maritime Continent over a more southerly path,the optimized statistical forecasting model obtains better improvements in MJO prediction. 展开更多
关键词 Madden-Julian Oscillation statistical forecasting Maritime Continent oceanic processes lagged multiple linear re-gression model
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Establishment and Effect Evaluation of Prediction Models of Ozone Concentration in Baoding City
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作者 Xiangru KONG Jiajia ZHANG +2 位作者 Luntao YAO Tianning YANG Rongfang YANG 《Meteorological and Environmental Research》 2025年第3期44-50,共7页
Firstly,based on the data of air quality and the meteorological data in Baoding City from 2017 to 2021,the correlations of meteorological elements and pollutants with O_(3)concentration were explored to determine the ... Firstly,based on the data of air quality and the meteorological data in Baoding City from 2017 to 2021,the correlations of meteorological elements and pollutants with O_(3)concentration were explored to determine the forecast factors of forecast models.Secondly,the O_(3)-8h concentration in Baoding City in 2021 was predicted based on the constructed models of multiple linear regression(MLR),backward propagation neural network(BPNN),and auto regressive integrated moving average(ARIMA),and the predicted values were compared with the observed values to test their prediction effects.The results show that overall,the MLR,BPNN and ARIMA models were able to forecast the changing trend of O_(3)-8h concentration in Baoding in 2021,but the BPNN model gave better forecast results than the ARIMA and MLR models,especially for the prediction of the high values of O_(3)-8h concentration,and the correlation coefficients between the predicted values and the observed values were all higher than 0.9 during June-September.The mean error(ME),mean absolute error(MAE),and root mean square error(RMSE)of the predicted values and the observed values of daily O_(3)-8h concentration based on the BPNN model were 0.45,19.11 and 24.41μg/m 3,respectively,which were significantly better than those of the MLR and ARIMA models.The prediction effects of the MLR,BPNN and ARIMA models were the best at the pollution level,followed by the excellent level,and it was the worst at the good level.In comparison,the prediction effect of BPNN model was better than that of the MLR and ARIMA models as a whole,especially for the pollution and excellent levels.The TS scores of the BPNN model were all above 66%,and the PC values were above 86%.The BPNN model can forecast the changing trend of O_(3)concentration more accurately,and has a good practical application value,but at the same time,the predicted high values of O_(3)concentration should be appropriately increased according to error characteristics of the model. 展开更多
关键词 Ozone(O_(3)) Multiple linear regression model Back propagation neural network model Auto regressive integrated moving average model TS
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Federated Learning Model for Auto Insurance Rate Setting Based on Tweedie Distribution 被引量:1
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作者 Tao Yin Changgen Peng +2 位作者 Weijie Tan Dequan Xu Hanlin Tang 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第1期827-843,共17页
In the assessment of car insurance claims,the claim rate for car insurance presents a highly skewed probability distribution,which is typically modeled using Tweedie distribution.The traditional approach to obtaining ... In the assessment of car insurance claims,the claim rate for car insurance presents a highly skewed probability distribution,which is typically modeled using Tweedie distribution.The traditional approach to obtaining the Tweedie regression model involves training on a centralized dataset,when the data is provided by multiple parties,training a privacy-preserving Tweedie regression model without exchanging raw data becomes a challenge.To address this issue,this study introduces a novel vertical federated learning-based Tweedie regression algorithm for multi-party auto insurance rate setting in data silos.The algorithm can keep sensitive data locally and uses privacy-preserving techniques to achieve intersection operations between the two parties holding the data.After determining which entities are shared,the participants train the model locally using the shared entity data to obtain the local generalized linear model intermediate parameters.The homomorphic encryption algorithms are introduced to interact with and update the model intermediate parameters to collaboratively complete the joint training of the car insurance rate-setting model.Performance tests on two publicly available datasets show that the proposed federated Tweedie regression algorithm can effectively generate Tweedie regression models that leverage the value of data fromboth partieswithout exchanging data.The assessment results of the scheme approach those of the Tweedie regressionmodel learned fromcentralized data,and outperformthe Tweedie regressionmodel learned independently by a single party. 展开更多
关键词 Rate setting Tweedie distribution generalized linear models federated learning homomorphic encryption
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CRB:A new rumor blocking algorithm in online social networks based on competitive spreading model and influence maximization 被引量:1
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作者 董晨 徐桂琼 孟蕾 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第8期588-604,共17页
The virtuality and openness of online social platforms make networks a hotbed for the rapid propagation of various rumors.In order to block the outbreak of rumor,one of the most effective containment measures is sprea... The virtuality and openness of online social platforms make networks a hotbed for the rapid propagation of various rumors.In order to block the outbreak of rumor,one of the most effective containment measures is spreading positive information to counterbalance the diffusion of rumor.The spreading mechanism of rumors and effective suppression strategies are significant and challenging research issues.Firstly,in order to simulate the dissemination of multiple types of information,we propose a competitive linear threshold model with state transition(CLTST)to describe the spreading process of rumor and anti-rumor in the same network.Subsequently,we put forward a community-based rumor blocking(CRB)algorithm based on influence maximization theory in social networks.Its crucial step is to identify a set of influential seeds that propagate anti-rumor information to other nodes,which includes community detection,selection of candidate anti-rumor seeds and generation of anti-rumor seed set.Under the CLTST model,the CRB algorithm has been compared with six state-of-the-art algorithms on nine online social networks to verify the performance.Experimental results show that the proposed model can better reflect the process of rumor propagation,and review the propagation mechanism of rumor and anti-rumor in online social networks.Moreover,the proposed CRB algorithm has better performance in weakening the rumor dissemination ability,which can select anti-rumor seeds in networks more accurately and achieve better performance in influence spread,sensitivity analysis,seeds distribution and running time. 展开更多
关键词 online social networks rumor blocking competitive linear threshold model influence maximization
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Comparison of isotope-based linear and Bayesian mixing models in determining moisture recycling ratio
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作者 XIAO Yanqiong WANG Liwei +5 位作者 WANG Shengjie Kei YOSHIMURA SHI Yudong LI Xiaofei Athanassios A ARGIRIOU ZHANG Mingjun 《Journal of Arid Land》 SCIE CSCD 2024年第6期739-751,共13页
Stable water isotopes are natural tracers quantifying the contribution of moisture recycling to local precipitation,i.e.,the moisture recycling ratio,but various isotope-based models usually lead to different results,... Stable water isotopes are natural tracers quantifying the contribution of moisture recycling to local precipitation,i.e.,the moisture recycling ratio,but various isotope-based models usually lead to different results,which affects the accuracy of local moisture recycling.In this study,a total of 18 stations from four typical areas in China were selected to compare the performance of isotope-based linear and Bayesian mixing models and to determine local moisture recycling ratio.Among the three vapor sources including advection,transpiration,and surface evaporation,the advection vapor usually played a dominant role,and the contribution of surface evaporation was less than that of transpiration.When the abnormal values were ignored,the arithmetic averages of differences between isotope-based linear and the Bayesian mixing models were 0.9%for transpiration,0.2%for surface evaporation,and–1.1%for advection,respectively,and the medians were 0.5%,0.2%,and–0.8%,respectively.The importance of transpiration was slightly less for most cases when the Bayesian mixing model was applied,and the contribution of advection was relatively larger.The Bayesian mixing model was found to perform better in determining an efficient solution since linear model sometimes resulted in negative contribution ratios.Sensitivity test with two isotope scenarios indicated that the Bayesian model had a relatively low sensitivity to the changes in isotope input,and it was important to accurately estimate the isotopes in precipitation vapor.Generally,the Bayesian mixing model should be recommended instead of a linear model.The findings are useful for understanding the performance of isotope-based linear and Bayesian mixing models under various climate backgrounds. 展开更多
关键词 moisture recycling stable water isotope linear mixing model Bayesian mixing model China
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Extended linear regression model for vessel trajectory prediction with a-priori AIS information
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作者 Christiaan Neil Burger Waldo Kleynhans Trienko Lups Grobler 《Geo-Spatial Information Science》 CSCD 2024年第1期202-220,共19页
As maritime activities increase globally,there is a greater dependency on technology in monitoring,control,and surveillance of vessel activity.One of the most prominent systems for monitoring vessel activity is the Au... As maritime activities increase globally,there is a greater dependency on technology in monitoring,control,and surveillance of vessel activity.One of the most prominent systems for monitoring vessel activity is the Automatic Identification System(AIS).An increase in both vessels fitted with AIS transponders and satellite and terrestrial AIS receivers has resulted in a significant increase in AIS messages received globally.This resultant rich spatial and temporal data source related to vessel activity provides analysts with the ability to perform enhanced vessel movement analytics,of which a pertinent example is the improvement of vessel location predictions.In this paper,we propose a novel strategy for predicting future locations of vessels making use of historic AIS data.The proposed method uses a Linear Regression Model(LRM)and utilizes historic AIS movement data in the form of a-priori generated spatial maps of the course over ground(LRMAC).The LRMAC is an accurate low complexity first-order method that is easy to implement operationally and shows promising results in areas where there is a consistency in the directionality of historic vessel movement.In areas where the historic directionality of vessel movement is diverse,such as areas close to harbors and ports,the LRMAC defaults to the LRM.The proposed LRMAC method is compared to the Single-Point Neighbor Search(SPNS),which is also a first-order method and has a similar level of computational complexity,and for the use case of predicting tanker and cargo vessel trajectories up to 8 hours into the future,the LRMAC showed improved results both in terms of prediction accuracy and execution time. 展开更多
关键词 Automatic Identification System(AIS)data Linear Regression model(LRM) trajectory mining spatial map historic data trajectory prediction
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Estimation of Daily Global Solar Radiation with Different Sunshine-Based Models for Some Burundian Stations
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作者 Mathias Bashahu Gratien Ndacayisaba 《Energy and Power Engineering》 2024年第1期1-20,共20页
Sunshine duration (S) based empirical equations have been employed in this study to estimate the daily global solar radiation on a horizontal surface (G) for six meteorological stations in Burundi. Those equations inc... Sunshine duration (S) based empirical equations have been employed in this study to estimate the daily global solar radiation on a horizontal surface (G) for six meteorological stations in Burundi. Those equations include the Ångström-Prescott linear model and four amongst its derivatives, i.e. logarithmic, exponential, power and quadratic functions. Monthly mean values of daily global solar radiation and sunshine duration data for a period of 20 to 23 years, from the Geographical Institute of Burundi (IGEBU), have been used. For any of the six stations, ten single or double linear regressions have been developed from the above-said five functions, to relate in terms of monthly mean values, the daily clearness index () to each of the next two kinds of relative sunshine duration (RSD): and . In those ratios, G<sub>0</sub>, S<sub>0 </sub>and stand for the extraterrestrial daily solar radiation on a horizontal surface, the day length and the modified day length taking into account the natural site’s horizon, respectively. According to the calculated mean values of the clearness index and the RSD, each station experiences a high number of fairly clear (or partially cloudy) days. Estimated values of the dependent variable (y) in each developed linear regression, have been compared to measured values in terms of the coefficients of correlation (R) and of determination (R<sub>2</sub>), the mean bias error (MBE), the root mean square error (RMSE) and the t-statistics. Mean values of these statistical indicators have been used to rank, according to decreasing performance level, firstly the ten developed equations per station on account of the overall six stations, secondly the six stations on account of the overall ten equations. Nevertheless, the obtained values of those indicators lay in the next ranges for all the developed sixty equations:;;;, with . These results lead to assert that any of the sixty developed linear regressions (and thus equations in terms of and ), fits very adequately measured data, and should be used to estimate monthly average daily global solar radiation with sunshine duration for the relevant station. It is also found that using as RSD, is slightly more advantageous than using for estimating the monthly average daily clearness index, . Moreover, values of statistical indicators of this study match adequately data from other works on the same kinds of empirical equations. 展开更多
关键词 Clearness Index Two Kinds of Relative Sunshine Duration Ångström-Prescott Linear model and Four Derivatives Statistical Tests Six Burundian Stations
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Adaptive Random Effects/Coefficients Modeling
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作者 George J. Knafl 《Open Journal of Statistics》 2024年第2期179-206,共28页
Adaptive fractional polynomial modeling of general correlated outcomes is formulated to address nonlinearity in means, variances/dispersions, and correlations. Means and variances/dispersions are modeled using general... Adaptive fractional polynomial modeling of general correlated outcomes is formulated to address nonlinearity in means, variances/dispersions, and correlations. Means and variances/dispersions are modeled using generalized linear models in fixed effects/coefficients. Correlations are modeled using random effects/coefficients. Nonlinearity is addressed using power transforms of primary (untransformed) predictors. Parameter estimation is based on extended linear mixed modeling generalizing both generalized estimating equations and linear mixed modeling. Models are evaluated using likelihood cross-validation (LCV) scores and are generated adaptively using a heuristic search controlled by LCV scores. Cases covered include linear, Poisson, logistic, exponential, and discrete regression of correlated continuous, count/rate, dichotomous, positive continuous, and discrete numeric outcomes treated as normally, Poisson, Bernoulli, exponentially, and discrete numerically distributed, respectively. Example analyses are also generated for these five cases to compare adaptive random effects/coefficients modeling of correlated outcomes to previously developed adaptive modeling based on directly specified covariance structures. Adaptive random effects/coefficients modeling substantially outperforms direct covariance modeling in the linear, exponential, and discrete regression example analyses. It generates equivalent results in the logistic regression example analyses and it is substantially outperformed in the Poisson regression case. Random effects/coefficients modeling of correlated outcomes can provide substantial improvements in model selection compared to directly specified covariance modeling. However, directly specified covariance modeling can generate competitive or substantially better results in some cases while usually requiring less computation time. 展开更多
关键词 Adaptive Regression Correlated Outcomes Extended Linear Mixed modeling Fractional Polynomials Likelihood Cross-Validation Random Effects/Coefficients
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A Study of EM Algorithm as an Imputation Method: A Model-Based Simulation Study with Application to a Synthetic Compositional Data
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作者 Yisa Adeniyi Abolade Yichuan Zhao 《Open Journal of Modelling and Simulation》 2024年第2期33-42,共10页
Compositional data, such as relative information, is a crucial aspect of machine learning and other related fields. It is typically recorded as closed data or sums to a constant, like 100%. The statistical linear mode... Compositional data, such as relative information, is a crucial aspect of machine learning and other related fields. It is typically recorded as closed data or sums to a constant, like 100%. The statistical linear model is the most used technique for identifying hidden relationships between underlying random variables of interest. However, data quality is a significant challenge in machine learning, especially when missing data is present. The linear regression model is a commonly used statistical modeling technique used in various applications to find relationships between variables of interest. When estimating linear regression parameters which are useful for things like future prediction and partial effects analysis of independent variables, maximum likelihood estimation (MLE) is the method of choice. However, many datasets contain missing observations, which can lead to costly and time-consuming data recovery. To address this issue, the expectation-maximization (EM) algorithm has been suggested as a solution for situations including missing data. The EM algorithm repeatedly finds the best estimates of parameters in statistical models that depend on variables or data that have not been observed. This is called maximum likelihood or maximum a posteriori (MAP). Using the present estimate as input, the expectation (E) step constructs a log-likelihood function. Finding the parameters that maximize the anticipated log-likelihood, as determined in the E step, is the job of the maximization (M) phase. This study looked at how well the EM algorithm worked on a made-up compositional dataset with missing observations. It used both the robust least square version and ordinary least square regression techniques. The efficacy of the EM algorithm was compared with two alternative imputation techniques, k-Nearest Neighbor (k-NN) and mean imputation (), in terms of Aitchison distances and covariance. 展开更多
关键词 Compositional Data Linear Regression model Least Square Method Robust Least Square Method Synthetic Data Aitchison Distance Maximum Likelihood Estimation Expectation-Maximization Algorithm k-Nearest Neighbor and Mean imputation
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Analysis of radar fault prediction based on combined model 被引量:1
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作者 邵延君 马春茂 潘宏侠 《Journal of Measurement Science and Instrumentation》 CAS CSCD 2016年第1期44-47,共4页
Based on modeling principle of GM(1,1)model and linear regression model,a combined prediction model is established to predict equipment fault by the fitting of two models.The new prediction model takes full advantag... Based on modeling principle of GM(1,1)model and linear regression model,a combined prediction model is established to predict equipment fault by the fitting of two models.The new prediction model takes full advantage of prediction information provided by the two models and improves the prediction precision.Finally,this model is introduced to predict the system fault time according to the output voltages of a certain type of radar transmitter. 展开更多
关键词 grey linear regression model filtting radar fault prediction
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Insight into the sorption and desorption pattern of pyrrolizidine alkaloids and their N-oxides in acidic tea(Camellia sinensis)plantation soils 被引量:2
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作者 Yuting Lu Haolei Han +5 位作者 Yuexing Yi Yunfeng Chai ChenWang Xiangchun Zhang Xiangde Yang Hongping Chen 《Journal of Environmental Sciences》 2025年第2期350-363,共14页
Pyrrolizidine alkaloids(PAs)and their N-oxides(PANOs)are phytotoxins produced by various plant species and have been emerged as environmental pollutants.The sorption/desorption behaviors of PAs/PANOs in soil are cruci... Pyrrolizidine alkaloids(PAs)and their N-oxides(PANOs)are phytotoxins produced by various plant species and have been emerged as environmental pollutants.The sorption/desorption behaviors of PAs/PANOs in soil are crucial due to the horizontal transfer of these natural products from PA-producing plants to soil and subsequently absorbed by plant roots.This study firstly investigated the sorption/desorption behaviors of PAs/PANOs in tea plantation soils with distinct characteristics.Sorption amounts for seneciphylline(Sp)and seneciphylline-N-oxide(SpNO)in three acidic soils ranged from 2.9 to 5.9μg/g and 1.7 to 2.8μg/g,respectively.Desorption percentages for Sp and SpNO were from 22.2%to 30.5%and 36.1%to 43.9%.In the mixed PAs/PANOs systems,stronger sorption of PAs over PANOs was occurred in tested soils.Additionally,the Freundlich models more precisely described the sorption/desorption isotherms.Cation exchange capacity,sand content and total nitrogen were identified as major influencing factors by linear regression models.Overall,the soils exhibiting higher sorption capacities for compounds with greater hydrophobicity.PANOs were more likely to migrate within soils and be absorbed by tea plants.It contributes to the understanding of environmental fate of PAs/PANOs in tea plantations and provides basic data and clues for the development of PAs/PANOs reduction technology. 展开更多
关键词 Pyrrolizidine alkaloids Sorption-desorption behavior Tea plantation system Acidic soil Linear regression model
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Prediction Model of Secondary Substances in Anthocyanins Synthesis of Purple Corn
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作者 朱敏 史振声 +1 位作者 李凤海 王志斌 《Agricultural Science & Technology》 CAS 2010年第8期153-156,182,共5页
The aim of this study was to assay the polyphenols,flavonoid,polyphenol oxidase and phenylalnine ammonialyase which were relative to the anthocyanins synthesis of purple corn. The optimization of multiple linear regre... The aim of this study was to assay the polyphenols,flavonoid,polyphenol oxidase and phenylalnine ammonialyase which were relative to the anthocyanins synthesis of purple corn. The optimization of multiple linear regression model of anthocyanins synthesis was y=4.383 86-0.205 45x1+5.479 638x2+0.195 575x4. According to standard partial regression coefficient testing,the result indicated that polyphenols content was negatively correlated with anthocyanins and the relative influence to anthocyanins synthesis was-42.7%; flavonoid content and activity of polyphenol oxidase were positively correlated with anthocyanins of purple corn and the relative influence to anthocyanins synthesis were 71.45% and 73.32% respectively. There was no positive correlation between the activity of phenylalnine ammonialyase and anthocyanins of purple corn. The establishment of multiple linear regression model of anthocyanins synthesis was to provide theory foundation of producing anthocyanins in laboratory. 展开更多
关键词 Anthocyanins Flavonoid Multiple linear regression model Purple corn POLYPHENOLS Polyphenol oxidase Phenylalnine ammonialyase
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Robustness of Minimum Norm Quadratic Unbiased Estimator of Variance Under the General Linear Model
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作者 张宝学 罗季 李馨 《Journal of Beijing Institute of Technology》 EI CAS 2002年第1期97-100,共4页
Necessary and sufficient conditions for equalities between a 2 y′(I-P Xx)y and minimum norm quadratic unbiased estimator of variance under the general linear model, where a 2 is a known positive number, are... Necessary and sufficient conditions for equalities between a 2 y′(I-P Xx)y and minimum norm quadratic unbiased estimator of variance under the general linear model, where a 2 is a known positive number, are derived. Further, when the Gauss? Markov estimators and the ordinary least squares estimator are identical, a relative simply equivalent condition is obtained. At last, this condition is applied to an interesting example. 展开更多
关键词 general linear model orthogonal projector minimum norm quadratic unbiased estimator
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Mathematical Model and Simulation of Harmful Invasive Plant Control
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作者 马庆功 杨波 《Agricultural Science & Technology》 CAS 2014年第12期2057-2063,共7页
Plant invasion refers to the phenomenon that some plants grow too fast due to they are far away from the original living environment or predators, affecting the local environment. With the development of tourism and t... Plant invasion refers to the phenomenon that some plants grow too fast due to they are far away from the original living environment or predators, affecting the local environment. With the development of tourism and trade, the harm caused by invasive plants will be more and more serious. Therefore, it is necessary to ex- plore an effective method for controlling plant invasion through qualitative and quan- titative research. In this paper, the models were established for the early and late harmful plant invasion control. The huge computation was completed by the com- puter programming to obtain the optimal solutions of the models. The real meaning of the optimal solution was further discussed. Through numerical simulations and discussion, it could be concluded that the quantitative research on the invasive plant control had a certain application value. 展开更多
关键词 Invasive plant Linear programming model Logistic model Pontryagin minimum principle Numerical simulation
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Uncovering genes essential in domestication and breeding of sugar beet
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作者 Amar Singh Dhiman Nazgol Emrani +2 位作者 Eva Holtgrewe-Stukenbrock Mark Varrelmann Christian Jung 《The Crop Journal》 2025年第4期1224-1233,共10页
The genus Beta encompasses economically important root crops such as sugar and table beet.A Beta diversity set including the wild relative B.vulgaris ssp.maritima was grown in the field,and a large phenotypic diversit... The genus Beta encompasses economically important root crops such as sugar and table beet.A Beta diversity set including the wild relative B.vulgaris ssp.maritima was grown in the field,and a large phenotypic diversity was observed.The genomes of 290 accessions were sequenced,and more than 10 million high-quality SNPs were employed to study genetic diversity.A genome-wide association study was performed,and marker-trait associations were found for nine phenotypic traits.The candidate gene within the M locus controlling monogermity on chromosome 4 was previously unknown.The most significant association for monogermity was identified at the end of chromosome 4.Within this region,a non-synonymous mutation within the zinc-finger domain of the WIP2 gene co-segregated with monogermity.This gene plays a regulatory role in AGL8/FUL in Arabidopsis.Intriguingly,commercial hybrids are in a heterozygous state at this position.Thus,the long-sought gene for monogermity was identified in this study.Red and yellow pigmentation due to betalain accumulation in shoots and roots is an important characteristic of table and leaf beets.The strongest associations were found upstream or downstream of two genes encoding Cytochrome P450 and anthocyanin MYB-like transcription factor proteins involved in betalain biosynthesis.Significant associations for Cercospora leaf spot resistance were identified on chromosomes 1,2,7,and 9.The associated regions harbor genes encoding proteins with leucinerich repeats and nucleotide binding sites whose homologs are major constituents of plant-pathogen defense. 展开更多
关键词 Beta vulgaris GWAS Population structure Mixed linear model Monogermity Bolting time Cercospora leaf spot
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The transmuted epsilon distribution with applications in reliability engineering
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作者 Christophe Chesneau Hassan S.Bakouch +1 位作者 Idika E.Okorie Bader Almohaimeed 《Applied Mathematics(A Journal of Chinese Universities)》 2025年第2期395-412,共18页
Since its inception,the epsilon distribution has piqued the interest of statisticians.It has been successfully used to solve a variety of statistical problems.In this article,we propose to use the quadratic rank trans... Since its inception,the epsilon distribution has piqued the interest of statisticians.It has been successfully used to solve a variety of statistical problems.In this article,we propose to use the quadratic rank transmutation map mechanism to extend this distribution.This mechanism is not new;it was already used to improve the modeling capabilities of a number of existing distributions.For the original epsilon distribution,we expect the same benefits.As a result,we implement the transmuted epsilon distribution as a flexible three-parameter distribution with a bounded domain.We demonstrate its key features,focusing on the properties of its distributional mechanism and conducting quantile and moment analyses.Applications of the model are presented using two data sets.We also perform a regression analysis based on this distribution. 展开更多
关键词 epsilon distribution quadratic rank transmutation map QUANTILE estimation generalized linear modelling regression
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The Month-to-Year Precursory and Synchronous Inherent Connections between Global Oceanic Modes and Extreme Precipitation over China
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作者 Xiaoyu LIU Yu ZHANG +6 位作者 Bian HE Yimin LIU Guoxiong WU Jianjun XU Qing BAO Wenting HU Jiangyu MAO 《Advances in Atmospheric Sciences》 2025年第8期1513-1532,共20页
The multiscale variability in summer extreme persistent precipitation(SEPP)in China from 1961 to 2020 was investigated via three extreme precipitation indices:consecutive wet days,total precipitation amount,and daily ... The multiscale variability in summer extreme persistent precipitation(SEPP)in China from 1961 to 2020 was investigated via three extreme precipitation indices:consecutive wet days,total precipitation amount,and daily precipitation intensity.The relationships between precursory and concurrent global oceanic modes and SEPP were identified via a generalized linear model(GLM).The influence of oceanic modes on SEPP was finally investigated via numerical simulations.The results revealed that the climatological SEPP(≥14 days)mainly appears across the Tibetan Plateau,Yunnan–Guizhou Plateau,and South China coast.The first EOF mode for all three indices showed strong signals over the Yangtze River.Further analysis via the GLM suggested that the positive phases of the tropical North Atlantic(TNA)in autumn,ENSO in winter,the Indian Ocean Basin(IOB)in spring,and the western North Pacific(WNP)in summer emerged as the most effective precursory factors of SEPP,which could serve as preceding signals for future predictions,contributing 30.2%,36.4%,38.0%,and 55.6%,respectively,to the GLM.Sensitivity experiments revealed that SST forcing in all four seasons contributes to SEPP over China,whereas the winter and summer SST warming over the Pacific and Indian Ocean(IO)contributes the most.Diagnosis of the hydrological cycle suggested that water vapor advection predominantly originates from the western Pacific and IO in summer,driven by the strengthened subtropical high and Asian summer monsoon(ASM).The enhanced vertical water vapor transport is attributed to stronger upward motion across all four seasons.These findings are helpful for better understanding SEPP variabilities and their prediction under SST warming. 展开更多
关键词 extreme precipitation Asian summer monsoon consecutive wet days oceanic modes generalized linear model ENSO
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The Moderating Role of Control Strategies on the Relationship between Negative Emotions and QoL in the Elderly:A Longitudinal Study
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作者 Ran Ma Chunyang Zhang Wei Xu 《International Journal of Mental Health Promotion》 2025年第4期469-483,共15页
Maintaining optimal quality of life(QoL)is a pivotal for“successful aging”.Understanding how the QoL of the elderly develops and what role psychological factors play in its development will help improve QoL from a p... Maintaining optimal quality of life(QoL)is a pivotal for“successful aging”.Understanding how the QoL of the elderly develops and what role psychological factors play in its development will help improve QoL from a psychological perspective.Embedded within the lifespan theory of control,this longitudinal study aimed to(1)map the temporal trajectory of QoL among Chinese older adults,(2)examine differential effects of tripartite negative emotions(stress,anxiety,depression),and(3)test themoderating role of control strategies(goal engagement,goal disengagement,self-protection)in emotion-QoL dynamics.A prospective cohort of 345 community-dwelling older adults(Mage=83.84±8.49 years;55.1%female)completed validated measures-SF-36 for QoL,DASS-21 for negative emotions,and an adapted Control Strategies Questionnaire(CAS)-at three waves spanning 12 months.Hierarchical linear modeling(HLM)with time-nested structure analyzed intraindividual changes and interindividual differences.QoL exhibited a significant linear decline over time(β=−4.75,p<0.001).Stress(β=−14.12,p<0.001)and anxiety(β=−11.24,p<0.001)robustly predicted QoL decline,whereas depression showed no significant effect.Control strategies had divergent associations:goal engagement(β=3.51,p<0.001)and self-protection(β=2.38,p=0.015)predicted higher baseline QoL,while goal disengagement accelerated decline(β=−7.00,p<0.001;interaction with time:β=−2.46,p<0.001).Contrary to hypotheses,control strategies did not moderate emotion-QoL associations(ΔR2=0.02,p=0.21).The results showed that stress and anxiety played an important role in the QoL of the elderly.At the same time,goal engagement and self-protection were beneficial to the QoL of the elderly,while goal disengagement was not conducive to QoL and its development among the elderly.Meanwhile,the negative effect of anxiety and stress on the QoL of the elderly was not affected by the control strategies. 展开更多
关键词 Negative emotions quality of life(QoL) older adults control strategies hierarchical linear model lifespan theory of control
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Doline susceptibility mapping using multisource data in the karst aquifers of Saldaran mountain,High Zagros Belt
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作者 Peyman MOHAMMADI-AHMADMAHMOUDI Somaiyeh KHALEGHI Mohsen EHTESHAMI-MOINABADI 《Journal of Mountain Science》 2025年第2期422-435,共14页
Doline susceptibility mapping(DSM)in karst aquifer is important in terms of estimating the vulnerability of the aquifer to pollutants,estimating the infiltration rate,and infrastructures exposed to the development of ... Doline susceptibility mapping(DSM)in karst aquifer is important in terms of estimating the vulnerability of the aquifer to pollutants,estimating the infiltration rate,and infrastructures exposed to the development of dolines.In this research,doline susceptibility map was prepared in Saldaran mountain by generalized linear model(GLM)using 14 affecting parameters extracted from satellite images,digital elevation model,and geology map.Only 8 parameters have been inputted to the model which had correlation with dolines.In this regards,306 dolines were identified by the photogrammetric Unmanned Aerial Vehicles(UAV)method in 600 hectares of Salderan lands and then,these data were divided into the training(70%)and testing(30%)data for modelling.The results of DSM modeling showed that classified probability of doline occurrences in the Saldaran mountain were as follow:16.5%of the area high to very high,72%in the class of low to very low,and 5%in the moderate class.Also,locally,in Saldaran mountain,the Pirghar aquifer has the highest potential for the doline development,followed by Bagh Rostam and Sarab aquifers.Also,the precipitation,digital elevation model,Topographic Position Index,drainage density,slope,TRASP(transformed the circular aspect to a radiation index),Snow-Covered Days and vegetation cover index are of highest importance in the DSM modeling,respectively.Accurate evaluation of the model using the Receiver Operating Characteristics(ROC)curve represents a very good accuracy(AUC=0.953)of the DSM model. 展开更多
关键词 Doline susceptibility mapping UAV photogrammetry Karst aquifers Generalized linear model(GLM) High Zagros Belt
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