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H–He Demixing Driven by Anisotropic Hydrogen Diffusion 被引量:1
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作者 Xiaoju Chang Dongdong Kang +1 位作者 Bo Chen Jiayu Dai 《Chinese Physics Letters》 2025年第5期33-42,共10页
The dynamics of phase separation in H–He binary systems within gas giants such as Jupiter and Saturn exhibit remarkable complexity, yet lack systematic investigation. Through large-scale machine-learning-accelerated ... The dynamics of phase separation in H–He binary systems within gas giants such as Jupiter and Saturn exhibit remarkable complexity, yet lack systematic investigation. Through large-scale machine-learning-accelerated molecular dynamics simulations spanning broad temperature-pressure-composition(2000–10000 K, 1–7 Mbar,pure H to pure He) regimes, we systematically determine self and mutual diffusion coefficients in H–He systems and establish a six-dimensional framework correlating temperature, pressure, helium abundance, phase separation degree, diffusion coefficients, and anisotropy. Key findings reveal that hydrogen exhibits active directional migration with pronounced diffusion anisotropy, whereas helium passively aggregates in response. While the conventional mixing rule underestimates mutual diffusion coefficients by neglecting velocity cross-correlations,the assumption of an ideal thermodynamic factor(Q = 1) overestimates them due to unaccounted non-ideal thermodynamic effects—both particularly pronounced in strongly phase-separated regimes. Notably, hydrogen's dual role, anisotropic diffusion and bond stabilization via helium doping, modulates demixing kinetics. Large-scale simulations(216,000 atoms) propose novel phase-separation paradigms, such as “hydrogen bubble/wisp” formation, challenging the classical “helium rain” scenario, striving to bridge atomic-scale dynamics to planetary-scale phase evolution. 展开更多
关键词 molecular dynamics simulations gas giants helium diffusion h he systems hydrogen diffusion determine self mutual diffusion coefficients h he binary systems dynamics phase separation
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LoRa Sense:Sensing and Optimization of LoRa Link Behavior Using Path-Loss Models in Open-Cast Mines
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作者 Bhanu Pratap Reddy Bhavanam Prashanth Ragam 《Computer Modeling in Engineering & Sciences》 SCIE EI 2025年第1期425-466,共42页
The Internet of Things(IoT)has orchestrated various domains in numerous applications,contributing significantly to the growth of the smart world,even in regions with low literacy rates,boosting socio-economic developm... The Internet of Things(IoT)has orchestrated various domains in numerous applications,contributing significantly to the growth of the smart world,even in regions with low literacy rates,boosting socio-economic development.This study provides valuable insights into optimizing wireless communication,paving the way for a more connected and productive future in the mining industry.The IoT revolution is advancing across industries,but harsh geometric environments,including open-pit mines,pose unique challenges for reliable communication.The advent of IoT in the mining industry has significantly improved communication for critical operations through the use of Radio Frequency(RF)protocols such as Bluetooth,Wi-Fi,GSM/GPRS,Narrow Band(NB)-IoT,SigFox,ZigBee,and Long Range Wireless Area Network(LoRaWAN).This study addresses the optimization of network implementations by comparing two leading free-spreading IoT-based RF protocols such as ZigBee and LoRaWAN.Intensive field tests are conducted in various opencast mines to investigate coverage potential and signal attenuation.ZigBee is tested in the Tadicherla open-cast coal mine in India.Similarly,LoRaWAN field tests are conducted at one of the associated cement companies(ACC)in the limestone mine in Bargarh,India,covering both Indoor-toOutdoor(I2O)and Outdoor-to-Outdoor(O2O)environments.A robust framework of path-loss models,referred to as Free space,Egli,Okumura-Hata,Cost231-Hata and Ericsson models,combined with key performance metrics,is employed to evaluate the patterns of signal attenuation.Extensive field testing and careful data analysis revealed that the Egli model is the most consistent path-loss model for the ZigBee protocol in an I2O environment,with a coefficient of determination(R^(2))of 0.907,balanced error metrics such as Normalized Root Mean Square Error(NRMSE)of 0.030,Mean Square Error(MSE)of 4.950,Mean Absolute Percentage Error(MAPE)of 0.249 and Scatter Index(SI)of 2.723.In the O2O scenario,the Ericsson model showed superior performance,with the highest R^(2)value of 0.959,supported by strong correlation metrics:NRMSE of 0.026,MSE of 8.685,MAPE of 0.685,Mean Absolute Deviation(MAD)of 20.839 and SI of 2.194.For the LoRaWAN protocol,the Cost-231 model achieved the highest R^(2)value of 0.921 in the I2O scenario,complemented by the lowest metrics:NRMSE of 0.018,MSE of 1.324,MAPE of 0.217,MAD of 9.218 and SI of 1.238.In the O2O environment,the Okumura-Hata model achieved the highest R^(2)value of 0.978,indicating a strong fit with metrics NRMSE of 0.047,MSE of 27.807,MAPE of 27.494,MAD of 37.287 and SI of 3.927.This advancement in reliable communication networks promises to transform the opencast landscape into networked signal attenuation.These results support decision-making for mining needs and ensure reliable communications even in the face of formidable obstacles. 展开更多
关键词 Internet of things long range wireless area network ZigBee mining environments path-loss models coefficient of determination mean square error
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Evaluating the relative importance of predictors in Generalized Additive Models using the gam.hp R package 被引量:2
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作者 Jiangshan Lai Jing Tang +2 位作者 Tingyuan Li Aiying Zhang Lingfeng Mao 《Plant Diversity》 SCIE CAS CSCD 2024年第4期542-546,共5页
Generalized Additive Models(GAMs)are widely employed in ecological research,serving as a powerful tool for ecologists to explore complex nonlinear relationships between a response variable and predictors.Nevertheless,... Generalized Additive Models(GAMs)are widely employed in ecological research,serving as a powerful tool for ecologists to explore complex nonlinear relationships between a response variable and predictors.Nevertheless,evaluating the relative importance of predictors with concurvity(analogous to collinearity)on response variables in GAMs remains a challenge.To address this challenge,we developed an R package named gam.hp.gam.hp calculates individual R^(2) values for predictors,based on the concept of'average shared variance',a method previously introduced for multiple regression and canonical analyses.Through these individual R^(2)s,which add up to the overall R^(2),researchers can evaluate the relative importance of each predictor within GAMs.We illustrate the utility of the gam.hp package by evaluating the relative importance of emission sources and meteorological factors in explaining ozone concentration variability in air quality data from London,UK.We believe that the gam.hp package will improve the interpretation of results obtained from GAMs. 展开更多
关键词 Average shared variance coefficient of determination Commonality analysis GAMs Hierarchical partitioning Individual R^(2)
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Simulation of Runoff and Sediment Yield for a Kaneri Watershed Using SWAT Model 被引量:1
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作者 Vidula A. Swami Sushama S. Kulkarni 《Journal of Geoscience and Environment Protection》 2016年第1期1-15,共15页
Watershed as an entry point acts as a beginning to address the issues of sustainable rainwater management for improving livelihoods. Extraction of watershed parameters using Geographical Information System (GIS) and u... Watershed as an entry point acts as a beginning to address the issues of sustainable rainwater management for improving livelihoods. Extraction of watershed parameters using Geographical Information System (GIS) and use of simulation models is the current trend for hydrologic evaluation of watersheds. In the present study, the open Source Tool Quantum GIS 2.2.0 was used for preparation of maps to verify the spatial extent of the area. The Soil and Water Assessment Tool (SWAT) having an interface with Arc-View GIS software (ArcGIS 10.1 with Arc SWAT 2012 extension) was selected for the estimation of runoff and sediment yield from Kaneri watershed, located in Western Maharashtra region. The coefficient of determination (R<sup>2</sup>) for the monthly and yearly runoff was obtained as 0.849 and 0.951 respectively for the calibration period 1979 to 2000 and 0.801 and 0.950 respectively for the validation period 2001-2013. The R<sup>2</sup> value in estimating the monthly and yearly sediment yield during calibration period was computed as 0.722 and 0.788 respectively. The R<sup>2</sup> for monthly and yearly sediment yield values for validation period was observed to be 0.565 and 0.684 respectively. 展开更多
关键词 Arc SWAT CALIBRATION VALIDATION GIS RUNOFF Sediment Yield coefficient of Determination R2
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Economic Consequences of Gender Equality in Europe
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作者 Biljana T. Barakovi6 《Chinese Business Review》 2012年第3期334-341,共8页
This paper shows influence of gender equality on economy where it analyzed how gender equality in Europe has affected on the development of the frozen food industry and services related to childcare. The development o... This paper shows influence of gender equality on economy where it analyzed how gender equality in Europe has affected on the development of the frozen food industry and services related to childcare. The development of these industries has given a positive impulse to the development of the whole economy. In this analysis, it is used multiple regressions as one of the most important statistical methods. In the first part of this paper, it shows the connection among the growth of female employment, growth in frozen food expenditure and growth of GDP in United Kingdom. In the second part of paper, it shows the relationship among the growth of labor force participation of women, growth of number of kindergarten and growth of GDP in Hungary. To proof these relationships, it used a multiple regression model. This statistical model was tested by using the T schedule which showed that the model in both the analyses is correct. At the end of the paper, it presents that employment rate and GDP behaves in the same way in European Union. These analyses show that it is necessary to continue to strengthen gender equality if the policy makers want to achieve even greater economic growth. The issue of gender equality is a very important factor in creating employment policy, and statisticians should be more involved in process of employment policy and gender equality 展开更多
关键词 gender equality employment of women multiple linear regression model statistical tests coefficient of determination
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Development of Empirical Models for the Estimation of CBR Value of Soil from Their Index Properties: A Case Study of the Ogbia-Nembe Road in Niger Delta Region of Nigeria
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作者 Jonathan O. Irokwe Ify L. Nwaogazie Samuel Sule 《Open Journal of Civil Engineering》 CAS 2022年第4期648-664,共17页
This study developed empirical-mathematical models to predict the California Bearing Ratio (CBR) using soil index properties in Ogbia-Nembe road in the Niger Delta region of Nigeria. The determination of CBR of soil i... This study developed empirical-mathematical models to predict the California Bearing Ratio (CBR) using soil index properties in Ogbia-Nembe road in the Niger Delta region of Nigeria. The determination of CBR of soil is a laborious operation that requires a longer time and materials leading to increased cost and schedule;this can be reduced by adopting an empirical-mathematical model that can predict the CBR using other simpler soil index properties such as Plastic Limit (PL), the Liquid Limit (LL), the Plasticity Index (PI) and the Moisture Content (MC), which are less laborious and take lesser time to obtain. Thirteen models were developed to understand the relationship between these soil index properties: the independent variable and the California Bearing Ratio (CBR): the dependent variable;Six linear, Six quadratic and One multiple linear regression models were developed for this relationship. Analysis of variance (ANOVA) on the thirteen models showed that the Optimum Moisture Content (OMC) and the Maximum Dry Density (MDD) are better independent variables for the prediction of the CBR value of Ogbia-Nembe soil generating a quadratic model and a multiple linear regression model having a better coefficient of determination R<sup>2</sup> = 0.96 and 0.94 respectively, mean square error (MSE) of 0.74 and 1.152 respectively with Root mean square errors of 0.861 and 1.073 accordingly. These models were used to predict the CBR of the soil. The CBR values predicted by the model were further compared with those of the actual experimental test and found to be relatively consistent with minimal variance. This establishes that CBR of any soil can be predicted from the Index Property of the soil and this is more economical and takes lesser time and can be universally adopted for soil investigation. 展开更多
关键词 Multiple Regression Model Soil Index Properties Analysis of Variance California Bearing Ratio coefficient of Determination
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Zeno’s Paradoxes and Lie Tzu’s Dichotomic Wisdom Explained with Alpha Beta (αβ) Asymptotic Nonlinear Math (Including One Example on Second Order Nonlinear Phenomena)
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作者 Ralph W. Lai Melisa W. Lai-Becker Evgenios Agathokleous 《Journal of Applied Mathematics and Physics》 2023年第5期1209-1249,共41页
Zeno’s paradoxes are a set of philosophical problems that were first introduced by the ancient Greek philosopher Zeno of Elea. Here is the first attempt to use asymptotic approach and nonlinear concepts to address th... Zeno’s paradoxes are a set of philosophical problems that were first introduced by the ancient Greek philosopher Zeno of Elea. Here is the first attempt to use asymptotic approach and nonlinear concepts to address the paradoxes. Among the paradoxes, two of the most famous ones are Zeno’s Room Walk and Zeno’s Achilles. Lie Tsu’s pole halving dichotomy is also discussed in relation to these paradoxes. These paradoxes are first-order nonlinear phenomena, and we expressed them with the concepts of linear and nonlinear variables. In the new nonlinear concepts, variables are classified as either linear or nonlinear. Changes in linear variables are simple changes, while changes in nonlinear variables are nonlinear changes relative to their asymptotes. Continuous asymptotic curves are used to describe and derive the equations for expressing the relationship between two variables. For example, in Zeno’s Room Walk, the equations and curves for a person to walk from the initial wall towards the other wall are different from the equations and curves for a person to walk from the other wall towards the initial wall. One walk has a convex asymptotic curve with a nonlinear equation having two asymptotes, while the other walk has a concave asymptotic curve with a nonlinear equation having a finite starting number and a bottom asymptote. Interestingly, they have the same straight-line expression in a proportionality graph. The Appendix of this discussion includes an example of a second-order nonlinear phenomenon. . 展开更多
关键词 DICHOTOMY Asymptotic Concave and Convex Curve Upper and Bottom As-ymptote Cumulative and Demulative Numbers (Opposite to Cumulative Numbers) coefficient of Determination Skewed Bell Sigmoid Curve
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A Comparative Study of Two Tree-Based Models for Predicting Flyrock Velocity at Open Pit Bench Mining
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作者 Ezatullah Rawnaq Bassir Esmatyar +2 位作者 Akihiro Hamanaka Takashi Sasaoka Hideki Shimada 《Open Journal of Applied Sciences》 2024年第2期267-287,共21页
Blasting is a cost-effective technique to break hard rock volumes by using explosives in the mining and civil engineering realms. Moreover, although blasting is a designed process and plays an indispensable role in th... Blasting is a cost-effective technique to break hard rock volumes by using explosives in the mining and civil engineering realms. Moreover, although blasting is a designed process and plays an indispensable role in these industries, it can also have multiple adverse environmental impacts. One such effect is flyrock, which poses risks to nearby machinery, and residential structures, and can even lead to injuries or fatalities. To optimize blasting efficiency as well as restrict side effects, prediction of the blast aftereffects is vital. Therefore, the present work focuses on using two machine learning methods to predict the velocity of flyrock in the open pit mine. To address this issue, a comprehensive dataset was gathered from the open pit mine. Then, Decision Tree and Random Forest algorithms were employed to predict flyrock velocity. The Random Forest model demonstrated superior performance compared to the Decision Tree model. Nonetheless, the performance of the Decision Tree model was deemed satisfactory, as evidenced by its coefficient of determination value of 0.83, mean squared error (MSE) of 4.2, and mean absolute percentage error (MAPE) of 5.6%. Considering these metrics, it is reasonable to conclude that tree-based algorithms can be effective in predicting flyrock velocity. 展开更多
关键词 Flyrock Machine Learning Bench Blasting coefficient of Determination
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Application of ACP Nonlinear Math in Analyzing Arithmetic and Radiation Transmission Data (Application 1 & 2) [4-21-2024, 820P] (V)
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作者 Ralph W. Lai Melisa W. Lai-Becker Grace Cheng-Dodge 《Journal of Applied Mathematics and Physics》 2024年第6期2302-2319,共18页
In this study, we explore the application of ACP (asymptotic curve based and proportionality oriented) Alpha Beta (αβ) Nonlinear Math to analyze arithmetic and radiation transmission data. Specifically, we investiga... In this study, we explore the application of ACP (asymptotic curve based and proportionality oriented) Alpha Beta (αβ) Nonlinear Math to analyze arithmetic and radiation transmission data. Specifically, we investigate the relationship between two variables. The novel approach involves collecting elementary “y” data and subsequently analyzing the asymptotic cumulative or demulative (opposite of cumulative) Y data. In part I, we examine the connection between the common linear numbers and ideal nonlinear numbers. In part II, we delve into the relationship between X-ray energy and the radiation transmission for various thin film materials. The fundamental physical law asserts that the nonlinear change in continuous variable Y is negatively proportional to the nonlinear change in continuous variable X, expressed mathematically as dα = −Kdβ. Here: dα {Y, Yu, Yb} represents the change in Y, with Yu and Yb denoting the upper and baseline asymptote of Y. dβ {X, Xu, Xb} represents the change in X, with Xu and Xb denoting the upper and baseline asymptote of X. K represents the proportionality constant or rate constant, which varies based on equation arrangement. K is the key inferential factor for describing physical phenomena. 展开更多
关键词 Asymptotic Concave and Convex Curve Upper and Baseline Asymptote Demulative vs. Cumulative coefficient of Determination Proportionalityand Position Constant Skewed Bell and Sigmoid Curve
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Utilizing ACP Alpha Beta (αβ) Nonlinear Mathematics for Analyzing Astrophysics and Electrostatic Separation Data (Applications 3 and 4)
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作者 Ralph W. Lai Melisa W. Lai-Becker +1 位作者 Grace Cheng-Dodge Michael L. Rehmet 《Journal of Applied Mathematics and Physics》 2024年第11期3706-3727,共22页
Analyses of astrophysics and electrostatic separation data were illustrated with the Asymptotic Curve Based and Proportionality Oriented (ACP) nonlinear math for relating two physical variables. The fundamental physic... Analyses of astrophysics and electrostatic separation data were illustrated with the Asymptotic Curve Based and Proportionality Oriented (ACP) nonlinear math for relating two physical variables. The fundamental physical law asserts that the nonlinear change of continuous variable Y is proportional to the nonlinear change in continuous variable X. Mathematically, this is expressed as dα{Y, Yu, Yb} = −Kdβ{X, Xu, Xb}, with Yu, Yb, Xu, and Xb representing the upper and baseline asymptotes of Y and X. Y is the continuous cumulative numbers of the elementary y and X is the continuous cumulative numbers of elementary x. K is the proportionality constant or equally is the rate constant. 展开更多
关键词 Alpha Beta (αβ) Nonlinear Math Asymptotic Concave and Convex Curve Upper and Baseline Asymptote Demulative Numbers (Opposite to Cumulative Numbers) coefficient of Determination (COD) Proportionality and Position Constant Skewed Bell and Sigmoid Curve
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本刊英文版2025年68卷第9期(2031-2284)摘要
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《中国科学:数学》 北大核心 2025年第9期I0001-I0004,共4页
Quasi-admissible,raisable nilpotent orbits,and theta representations Fan Gao,Baiying Liu&Wan-Yu Tsai Abstract We study the quasi-admissibility and raisability of some nilpotent orbits of a covering group.In partic... Quasi-admissible,raisable nilpotent orbits,and theta representations Fan Gao,Baiying Liu&Wan-Yu Tsai Abstract We study the quasi-admissibility and raisability of some nilpotent orbits of a covering group.In particular,we determine the degree of the cover such that a given split nilpotent orbit is quasi-admissible and non-raisable.The speculated wavefront sets of theta representations are also computed explicitly and are shown to be quasi-admissible and non-raisable.Lastly,we determine the leading coefficients in the Harish-Chandra character expansion of the theta representations of covers of the general linear groups. 展开更多
关键词 theta representations determine leading coefficients determine degree cover nilpotent orbits quasi admissible raisable speculated wavefront sets nilpotent orbitsand
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glmm.hp: an R package for computing individual effect of predictors in generalized linear mixed models 被引量:27
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作者 Jiangshan Lai Yi Zou +2 位作者 Shuang Zhang Xiaoguang Zhang Lingfeng Mao 《Journal of Plant Ecology》 SCIE CSCD 2022年第6期1302-1307,共6页
Generalized linear mixed models(GLMMs)have been widely used in contemporary ecology studies.However,determination of the relative importance of collinear predictors(i.e.fixed effects)to response variables is one of th... Generalized linear mixed models(GLMMs)have been widely used in contemporary ecology studies.However,determination of the relative importance of collinear predictors(i.e.fixed effects)to response variables is one of the challenges in GLMMs.Here,we developed a novel R package,glmm.hp,to decompose marginal R2^(2)explained by fixed effects in GLMMs.The algorithm of glmm.hp is based on the recently proposed approach‘average shared variance’i.e.used for multivariate analysis.We explained the principle and demonstrated the use of this package by simulated dataset.The output of glmm.hp shows individual marginal R2^(2)s that can be used to evaluate the relative importance of predictors,which sums up to the overall marginal R2^(2).Overall,we believe the glmm.hp package will be helpful in the interpretation of GLMM outcomes. 展开更多
关键词 coefficient of determination commonality analysis fixed effect GLMM hierarchical partitioning marginal R2^(2) relative importance variance partitioning
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Studying beta diversity: ecological variation partitioning by multiple regression and canonical analysis 被引量:21
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作者 Pierre Legendre 《Journal of Plant Ecology》 SCIE 2008年第1期3-8,共6页
Aims Beta diversity is the variation in species composition among sites in a geographic region.Beta diversity is a key concept for understanding the functioning of ecosystems,for the conservation of biodiversity and f... Aims Beta diversity is the variation in species composition among sites in a geographic region.Beta diversity is a key concept for understanding the functioning of ecosystems,for the conservation of biodiversity and for ecosystem management.The present report describes how to analyse beta diversity from community composition and associated environmental and spatial data tables.Methods Beta diversity can be studied by computing diversity indices for each site and testing hypotheses about the factors that may explain the variation among sites.Alternatively,one can carry out a direct analysis of the community composition data table over the study sites,as a function of sets of environmental and spatial variables.These analyses are carried out by the statistical method of partitioning the variation of the diversity indices or the community composition data table with respect to environmental and spatial variables.Variation partitioning is briefly described herein.Important findings Variation partitioning is a method of choice for the interpretation of beta diversity using tables of environmental and spatial variables.Beta diversity is an interesting‘currency’for ecologists to compare either different sampling areas or different ecological communities cooccurring in an area.Partitioning must be based upon unbiased estimates of the variation of the community composition data table that is explained by the various tables of explanatory variables.The adjusted coefficient of determination provides such an unbiased estimate in both multiple regression and canonical redundancy analysis.After partitioning,one can test the significance of the fractions of interest and plot maps of the fitted values corresponding to these fractions. 展开更多
关键词 Adjusted coefficient of determination beta diversity BIODIVERSITY canonical redundancy analysis community composition variation partitioning
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Evaluation and modification of potential evapotranspiration methods in Beijing,China
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作者 Liu Haijun Li Yan +1 位作者 Zhang Ruihao Huang Guanhua 《International Journal of Agricultural and Biological Engineering》 SCIE EI CAS 2013年第4期9-18,共10页
In this study,seven widely used potential evapotranspiration(ETo)methods were evaluated by comparing with the FAO-56 Penman-Monteith method(PM method)to provide useful information for selecting appropriate ETo equatio... In this study,seven widely used potential evapotranspiration(ETo)methods were evaluated by comparing with the FAO-56 Penman-Monteith method(PM method)to provide useful information for selecting appropriate ETo equations under data-limited condition in Beijing,China.Statistical methods and parameters,namely linear regression,root mean squared error(RMSE)and mean bias error(MBE),were used to evaluate the seven ETo methods.Results showed that ETo estimated using Kimberly-Penman method have fairly close agreement with the PM method(referring to standard ETo),considering the coefficient of determination(R^(2))of 0.96,RMSE of 0.42 mm/day,and a coefficient of efficiency(E)of 0.96.Locally calibrated Penman and Doorenbos-Pruitt methods also have better agreement with the PM method,correspondingly with R^(2)of 0.99 and 0.95,RMSEs of 0.24 mm/day and 0.21 mm/day,and coefficients of efficiency of 1.02 and 0.99,respectively.The ETo is the most sensitive to vapor pressure deficit(VPD)and net radiation in the Beijing area.Hence,the VPD-based and VPD-radiation combined ETo methods were developed and calibrated.Results showed that the two developed methods performed well in ETo estimation.By fully considering the data-limit situation,the calibrated Turc method,VPD-based method and VPD-radiation-combined method may be attractive alternatives to the more complex Penman−Monteith method in Beijing. 展开更多
关键词 potential evapotranspiration Penman-Monteith method determination coefficient coefficient of efficiency BEIJING
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