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The Analysis of Gauss Radial Basis Functions and Its Application in Locating Olivine on the Moon
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作者 SONG Shicang SONG Xiaoyuan SONG Shuhan 《应用数学》 北大核心 2026年第1期173-181,共9页
Gauss radial basis functions(GRBF)are frequently employed in data fitting and machine learning.Their linear independence property can theoretically guarantee the avoidance of data redundancy.In this paper,one of the m... Gauss radial basis functions(GRBF)are frequently employed in data fitting and machine learning.Their linear independence property can theoretically guarantee the avoidance of data redundancy.In this paper,one of the main contributions is proving this property using linear algebra instead of profound knowledge.This makes it easy to read and understand this fundamental fact.The proof of linear independence of a set of Gauss functions relies on the constructing method for one-dimensional space and on the deducing method for higher dimensions.Additionally,under the condition of preserving the same moments between the original function and interpolating function,both the interpolating existence and uniqueness are proven for GRBF in one-dimensional space.The final work demonstrates the application of the GRBF method to locate lunar olivine.By combining preprocessed data using GRBF with the removing envelope curve method,a program is created to find the position of lunar olivine based on spectrum data,and the numerical experiment shows that it is an effective scheme. 展开更多
关键词 Gauss function Radial basis function Machine learning Lunar olivine locating Data fitting
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Applying the Radial Basis Function Method to Estimate the Distribution of Total Suspended Matter Concentration in Hangzhou Bay
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作者 CHEN Wanqian GAO Jinpeng +5 位作者 XU Minjie LIU Zezheng LI Bingtian LV Jing LI Shujiang SUN Junchuan 《Journal of Ocean University of China》 2025年第3期557-568,共12页
Ocean remote sensing satellites provide observations with high spatiotemporal resolution.However,the influence of clouds,fog,and haze frequently leads to significant data gaps.Accurate and effective estimation of thes... Ocean remote sensing satellites provide observations with high spatiotemporal resolution.However,the influence of clouds,fog,and haze frequently leads to significant data gaps.Accurate and effective estimation of these missing data is highly valuable for engineering and scientific research.In this study,the radial basis function(RBF)method is used to estimate the spatial distribution of total suspended matter(TSM)concentration in Hangzhou Bay using remote sensing data with severe data gaps.The estimation precision is validated by comparing the results with those of other commonly used interpolation methods,such as the Kriging method and the basic spline(B-spline)method.In addition,the applicability of the RBF method is explored.Results show that the estimation of the RBF method is significantly close to the observation in Hangzhou Bay.The average of the mean absolute error,mean relative error,and root mean square error in all the experiments is evidently smaller than those of the Kriging and B-spline interpolations,indicating that the proposed method is more appropriate for estimating the spatial distribution of the TSM in Hangzhou Bay.Finally,the TSM distribution in the blank observational area is predicted.This study can provide some reference values for handling watercolor remote sensing data. 展开更多
关键词 ocean remote sensing satellite total suspended matter concentration INTERPOLATION radial basis function Kriging method basic spline method
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New cubic rational basis with tension shape parameters 被引量:4
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作者 ZHU Yuan-peng HAN Xu-li 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2015年第3期273-298,共26页
By using the blossom approach, we construct four new cubic rational Bernsteinlike basis functions with two shape parameters, which form a normalized B-basis and include the cubic Bernstein basis and the cubic Said-Bal... By using the blossom approach, we construct four new cubic rational Bernsteinlike basis functions with two shape parameters, which form a normalized B-basis and include the cubic Bernstein basis and the cubic Said-Ball basis as special cases. Based on the new basis, we propose a class of C2 continuous cubic rational B-spline-like basis functions with two local shape parameters, which includes the cubic non-uniform B-spline basis as a special case.Their totally positive property is proved. In addition, we extend the cubic rational Bernsteinlike basis to a triangular domain which has three shape parameters and includes the cubic triangular Bernstein-B′ezier basis and the cubic triangular Said-Ball basis as special cases. The G1 continuous conditions are deduced for the joining of two patches. The shape parameters in the bases serve as tension parameters and play a foreseeable adjusting role on generating curves and patches. 展开更多
关键词 Bernstein basis Said-Ball basis tension shape parameter totally positive property B-spline basis Bernstein-Bezier basis
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Historical Basis,Theoretical Implication,and Practical Significance:A Three-Dimensional Analysis of Marx’s Thoughts on Clean Government
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作者 Faying Ding Cong Liu +1 位作者 Qun Wang Gongxu Tan 《Journal of Contemporary Educational Research》 2025年第7期346-355,共10页
Marx scientifically summarized the experience and lessons of the Paris Commune,deeply exposed the root causes of bourgeois corruption,and emphasized the purity and advancement of the construction of proletarian politi... Marx scientifically summarized the experience and lessons of the Paris Commune,deeply exposed the root causes of bourgeois corruption,and emphasized the purity and advancement of the construction of proletarian political parties and political power.The dictatorship of the proletariat puts forward the ideas of cheap government that eradicate corruption,realizes that the people are the masters of the country,implements democratic supervision of elections,simplifies the construction of institutions,lowers governance costs,and achieves higher efficiency.A deep understanding of the theoretical characteristics of Marx’s thoughts on integrity,democracy,and honor,and a profound clarification of the practical significance of Marx’s ideology on clean governance,combined with practical practice,will help promote the construction of a new system of anti-corruption and incorruption in our country,and will benefit our contemporary services.The construction of a type-oriented government system is conducive to deepening the construction of China’s national legal system. 展开更多
关键词 Marx Thoughts on clean government Historical basis Theoretical implications SIGNIFICANCE
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Research progress on therapeutic material basis and mechanism of Scutellaria barbata–Lobelia chinensis herb pair in the treatment of lung cancer
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作者 Xiao-Yun Liang Ke-Jin Xu +3 位作者 Jia Liu Wei-Dong Li Hai-Bing Hua Chen-Xu Wei 《Integrative Medicine Discovery》 2025年第21期1-12,共12页
Lung cancer remains a leading cause of cancer-related mortality globally,with conventional therapies(chemotherapy,targeted agents)limited by severe toxicities and poor durability.Traditional Chinese medicine(TCMs)herb... Lung cancer remains a leading cause of cancer-related mortality globally,with conventional therapies(chemotherapy,targeted agents)limited by severe toxicities and poor durability.Traditional Chinese medicine(TCMs)herb pairs,particularly Scutellaria barbata–Lobelia chinensis(SL),have emerged as promising alternatives for their multitarget anti-lung cancer activity,but their material basis and mechanisms need systematic clarification.In TCM practice,SL herb pair exerts“heat-clearing and toxin-resolving”effects,aligning with the therapeutic principle of“resolving toxin to suppress tumor”for lung cancer.Phytochemical and pharmacological studies confirm its key active components,including flavonoids(baicalein,luteolin,quercetin),alkaloids,and polysaccharides.These components synergistically act through core signaling pathways:inhibiting angiogenesis via HIF-1α/VEGF axis;inducing apoptosis/autophagy through PI3K/AKT/mTOR and SIRT1/AMPK pathways;suppressing epithelial-mesenchymal transition(EMT)by targeting TGF-β/Smad and Wnt/β-catenin pathways;and regulating immune microenvironment via NLRP3 inflammasome and Th1/Th2 balance.This review systematically summarizes the multi-component(flavonoids,alkaloids)and multi-pathway mechanisms of SL herb pair,validating the scientific connotation of TCM’s“multi-target therapy”paradigm.It provides a theoretical basis for clinical application of SL herb pair and inspires the development of innovative lung cancer therapies(e.g.,component-based nano-drugs),bridging TCM practice with modern pharmacology. 展开更多
关键词 Scutellaria barbata Lobelia chinensis herbal pair lung cancer therapeutic material basis action mechanism
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Bayesian analysis of Gamow resonances with reduced basis methods:from eigenvector continuation to post-emulation corrections
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作者 Ruo-Yu Cheng Zhi-Cheng Xu 《Nuclear Science and Techniques》 2025年第12期233-243,共11页
To study the uncertainty quantification of resonant states in open quantum systems,we developed a Bayesian framework by integrating a reduced basis method(RBM)emulator with the Gamow coupled-channel(GCC)approach.The R... To study the uncertainty quantification of resonant states in open quantum systems,we developed a Bayesian framework by integrating a reduced basis method(RBM)emulator with the Gamow coupled-channel(GCC)approach.The RBM,constructed via eigenvector continuation and trained on both bound and resonant configurations,enables the fast and accurate emulation of resonance properties across the parameter space.To identify the physical resonant states from the emulator’s output,we introduce an overlap-based selection technique that effectively isolates true solutions from background artifacts.By applying this framework to unbound nucleus ^(6)Be,we quantified the model uncertainty in the predicted complex energies.The results demonstrate relative errors of 17.48%in the real part and 8.24%in the imaginary part,while achieving a speedup of four orders of magnitude compared with the full GCC calculations.To further investigate the asymptotic behavior of the resonant-state wavefunctions within the RBM framework,we employed a Lippmann–Schwinger(L–S)-based correction scheme.This approach not only improves the consistency between eigenvalues and wavefunctions but also enables a seamless extension from real-space training data to the complex energy plane.By bridging the gap between bound-state and continuum regimes,the L–S correction significantly enhances the emulator’s capability to accurately capture continuum structures in open quantum systems. 展开更多
关键词 Uncertainty quantification Reduced basis method Resonance emulator Bayesian analysis Gamow coupled-channel model
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Research Progress of Mongolian Medicine and Effective Material Basis in the Treatment of Rheumatoid Arthritis
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作者 Wuriliga Cuilan BAI 《Medicinal Plant》 2025年第4期81-84,共4页
This paper reviews and summarizes the material basis that contribute to the efficacy of Mongolian medicine,as well as the advancements in research concerning both single drugs and compound prescriptions in Mongolian m... This paper reviews and summarizes the material basis that contribute to the efficacy of Mongolian medicine,as well as the advancements in research concerning both single drugs and compound prescriptions in Mongolian medicine for the treatment of rheumatoid arthritis(RA).The objective is to provide a reference for further in-depth research and the clinical application of Mongolian medicine in the management of RA,while also offering new insights for the development of more effective therapeutic agents and methods for treating this condition. 展开更多
关键词 Mongolian medicine Material basis Single drug Compound prescription Rheumatoid arthritis(RA)
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Material basis and sleep-improving mechanisms of Lily-Ziziphi Spinosae Semen decoction:systematic evidence from LC-MS,network pharmacology and animal experiments
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作者 Fan Jia Hui Zheng +5 位作者 Yao Xu Jiani Jiang Yuhang Wu Jianxin Liu Kai He Yong Yang 《Food Science and Human Wellness》 2025年第9期3735-3752,共18页
Lily-Ziziphi Spinosae Semen decoction(LZ)is known for its blood nourishing,mind calming,body sedation,and sleep promoting effects in traditional Chinese medicine.However,its material basis and underlying mechanisms ha... Lily-Ziziphi Spinosae Semen decoction(LZ)is known for its blood nourishing,mind calming,body sedation,and sleep promoting effects in traditional Chinese medicine.However,its material basis and underlying mechanisms have not yet been clearly defined.This study applies liquid chromatography-mass spectrometry,network pharmacology,and animal studies to reveal the material basis and sleep-improving mechanisms of LZ.The mixed decoction(LZ-ME)and single decoction(LZ-SE)were prepared to study their chemical components.Network pharmacology was used to predict the sleep-improving targets and signaling pathways of LZ.ICR mice were intragastrically administered saline(NC),melatonin(positive control group,0.50 mg/kg),low(12.90 g/kg),medium(25.70 g/kg),and high(38.60 g/kg)dose of LZ-ME and LZ-SH for 30 days.The results showed that LZ-ME could prolong the sleep duration and shorten the sleep latency in sodium barbiturate induced mice model.The results of chemical composition showed that total polysaccharides,total flavonoids,total saponins,and total alkaloids in LZ-ME were significantly higher than those in LZ-SE(177.20%,82.34%,30.58%,and 11.66%,respectively).A total of 58 chemical components were identified by ultra-high performance liquid chromatography-quadrupole time-of-flight mass spectrometry(UPLC-QTOF-MS),and 8 representative difference components of LZ-ME and LZ-SE were found.LZ-ME significantly increased tumor necrosis factor-α(TNF-α)in mice serum and neurotransmitterγ-aminobutyric acid(GABA)levels in mice hippocampus,decreased dopamine(DA)and glutamate(Glu)levels in mice hippocampus(P<0.05).Furthermore,LZ-ME up-regulated the abundance of the beneficial bacteria Lactobacillus and Eubacterium_R,down-regulated the abundance of the harmful bacteria Lachnospiraceae etc.The polysaccharides,flavonoids(spinosin and 6‴-feruloylspinosin)and saponins(jujuboside A and jujuboside B)were the main material bases for the sleep-promoting effects of LZ.These compounds may directly enhance levels of the GABA,reduced levels of Glu and DA and improve TNF-αlevels.And they also may indirectly regulate GABA levels by influencing the relative abundance of Lactobacillus and Eubacterium. 展开更多
关键词 Lily-Ziziphi Spinosae Semen decoction INSOMNIA Material basis Mechanism of action
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A Basis Function Generation Based Digital Predistortion Concurrent Neural Network Model for RF Power Amplifiers
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作者 SHAO Jianfeng HONG Xi +2 位作者 WANG Wenjie LIN Zeyu LI Yunhua 《ZTE Communications》 2025年第1期71-77,共7页
This paper proposes a concurrent neural network model to mitigate non-linear distortion in power amplifiers using a basis function generation approach.The model is designed using polynomial expansion and comprises a f... This paper proposes a concurrent neural network model to mitigate non-linear distortion in power amplifiers using a basis function generation approach.The model is designed using polynomial expansion and comprises a feedforward neural network(FNN)and a convolutional neural network(CNN).The proposed model takes the basic elements that form the bases as input,defined by the generalized memory polynomial(GMP)and dynamic deviation reduction(DDR)models.The FNN generates the basis function and its output represents the basis values,while the CNN generates weights for the corresponding bases.Through the concurrent training of FNN and CNN,the hidden layer coefficients are updated,and the complex multiplication of their outputs yields the trained in-phase/quadrature(I/Q)signals.The proposed model was trained and tested using 300 MHz and 400 MHz broadband data in an orthogonal frequency division multiplexing(OFDM)communication system.The results show that the model achieves an adjacent channel power ratio(ACPR)of less than-48 d B within a 100 MHz integral bandwidth for both the training and test datasets. 展开更多
关键词 basis function generation digital predistortion generalized memory polynomial dynamic deviation reduction neural network
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Transient analysis of functionally graded curved shells using a nonuniform shape parameter integrated radial basis function approach
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作者 Vay Siu Lo Andrzej Katunin Thien Tich Truong 《Theoretical & Applied Mechanics Letters》 2025年第3期296-308,共13页
In this study,an improved integrated radial basis function with nonuniform shape parameter is introduced.The proposed shape parameter varies in each support domain and is defined byθ=1/d_(max),where d_(max)is the max... In this study,an improved integrated radial basis function with nonuniform shape parameter is introduced.The proposed shape parameter varies in each support domain and is defined byθ=1/d_(max),where d_(max)is the maximum distance of any pair of nodes in the support domain.The proposed method is verified and shows good performance.The results are stable and accurate with any number of nodes and an arbitrary nodal distribution.Notably,the support domain should be large enough to obtain accurate results.This method is then applied for transient analysis of curved shell structures made from functionally graded materials with complex geometries.Through several numerical examples,the accuracy of the proposed approach is demonstrated and discussed.Additionally,the influence of various factors on the dynamic behavior of the structures,including the power-law index,different materials,loading conditions,and geometrical parameters of the structures,was investigated. 展开更多
关键词 Integrated radial basis function Shape parameter Functionally graded material Curved shell Transient analysis
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Optimizing basis wave functions in the generator coordinate method for microscopic cluster models (Ⅰ)
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作者 Yi‑Fan Liu Bo Zhou Yu‑Gang Ma 《Nuclear Science and Techniques》 2025年第10期183-191,共9页
We employed random distributions and gradient descent methods for the Generator Coordinate Method(GCM)to identify effective basis wave functions,taking halo nuclei ^(6)He and ^(6)Li as examples.By comparing the ground... We employed random distributions and gradient descent methods for the Generator Coordinate Method(GCM)to identify effective basis wave functions,taking halo nuclei ^(6)He and ^(6)Li as examples.By comparing the ground state(0^(+))energy of ^(6)He and the excited state(0^(+))energy of 6 Li calculated with various random distributions and manually selected generation coordinates,we found that the heavy tail characteristic of the logistic distribution better describes the features of the halo nuclei.Subsequently,the Adam algorithm from machine learning was applied to optimize the basis wave functions,indicating that a limited number of basis wave functions can approximate the converged values.These results offer some empirical insights for selecting basis wave functions and contribute to the broader application of machine learning methods in predicting effective basis wave functions. 展开更多
关键词 Generator Coordinate Method Effective basis wave functions Nuclear cluster model Machine learning Halo nuclei
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Generalized Energy-Based Fragmentation DLPNO-CCSD(T)Approach at Complete Basis Set Limit and Its Application to Benzene Clusters
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作者 Yan Sun Benkun Hong +1 位作者 Wei Li Shuhua Li 《Chinese Journal of Chemical Physics》 2025年第3期347-355,I0061-I0105,I0109,共55页
Accurate description of noncova-lent interactions in large systems is challenging due to the require-ment of high-level electron corre-lation methods.The generalized energy-based fragmentation(GEBF)approach,in conjunc... Accurate description of noncova-lent interactions in large systems is challenging due to the require-ment of high-level electron corre-lation methods.The generalized energy-based fragmentation(GEBF)approach,in conjunc-tion with the domain-based local pair natural orbital(DLPNO)method,has been applied to assess the average binding energies(ABEs)of large benzene clus-ters,specifically(C6H6)13,at the coupled cluster singles and doubles with perturbative triples correction[CCSD(T)]level and the complete basis set(CBS)limit.Utilizing GEBF-DLPNO-CCSD(T)/CBS ABEs as benchmarks,various DFT functionals were evaluated.It was found that several functionals with empirical dispersion correction,including M06-2X-D3,B3LYP-D3(BJ),and PBE-D3(BJ),provide accurate descriptions of the ABEs for(C6H6)13 clusters.Additionally,the M06-2X-D3 functional was used to calculate the ABEs and relative stabili-ties of(C6H6)n clusters for n=11,12,13,14,and 15 revealing that the(C6H6)13 cluster ex-hibits the highest relative stability.These findings align with experimental evidence suggest-ing that n=13 is one of the magic numbers for benzene clusters(C6H6)n,with n≤30. 展开更多
关键词 Generalized energy-based fragmentation approach Coupled cluster Complete basis set limit Benzene cluster Dispersion interactions
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Radial Basis Function Neural Network Adaptive Controller for Wearable Upper-Limb Exoskeleton with Disturbance Observer
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作者 Mohammad Soleimani Amiri Sahbi Boubaker +1 位作者 Rizauddin Ramli Souad Kamel 《Computer Modeling in Engineering & Sciences》 2025年第9期3113-3133,共21页
Disability is defined as a condition that makes it difficult for a person to perform certain vital activities.In recent years,the integration of the concepts of intelligence in solving various problems for disabled pe... Disability is defined as a condition that makes it difficult for a person to perform certain vital activities.In recent years,the integration of the concepts of intelligence in solving various problems for disabled persons has become more frequent.However,controlling an exoskeleton for rehabilitation presents challenges due to their nonlinear characteristics and external disturbances caused by the structure itself or the patient wearing the exoskeleton.To remedy these problems,this paper presents a novel adaptive control strategy for upper-limb rehabilitation exoskeletons,addressing the challenges of nonlinear dynamics and external disturbances.The proposed controller integrated a Radial Basis Function Neural Network(RBFNN)with a disturbance observer and employed a high-dimensional integral Lyapunov function to guarantee system stability and trajectory tracking performance.In the control system,the role of the RBFNN was to estimate uncertain signals in the dynamic model,while the disturbance observer tackled external disturbances during trajectory tracking.Artificially created scenarios for Human-Robot interactive experiments and periodically repeated reference trajectory experiments validated the controller’s performance,demonstrating efficient tracking.The proposed controller is found to achieve superior tracking accuracy with Root-Mean-Squared(RMS)errors of 0.022-0.026 rad for all joints,outperforming conventional Proportional-Integral-Derivative(PID)by 73%and Neural-Fuzzy Adaptive Control(NFAC)by 389.47%lower error.These results suggested that the RBFNN adaptive controller,coupled with disturbance compensation,could serve as an effective rehabilitation tool for upper-limb exoskeletons.These results demonstrate the superiority of the proposed method in enhancing rehabilitation accuracy and robustness,offering a promising solution for the control of upper-limb assistive devices.Based on the obtained results and due to their high robustness,the proposed control schemes can be extended to other motor disabilities,including lower limb exoskeletons. 展开更多
关键词 Adaptive neural network controller disturbance observer upper-limb exoskeleton rehabilitation robotics Lyapunov stability radial basis function network
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Lp Stability of the Truncated Hierarchical B-Spline Basis
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作者 Jianping ZHOU Renhong WANG Chongjun LI 《Journal of Mathematical Research with Applications》 CSCD 2017年第6期697-709,共13页
The truncated hierarchical B-spline basis has been proposed for adaptive data fitting and has already drawn a lot of attention in theory and applications. However the stability with respect to the Lp-norm, 1 ≤ p 〈 ... The truncated hierarchical B-spline basis has been proposed for adaptive data fitting and has already drawn a lot of attention in theory and applications. However the stability with respect to the Lp-norm, 1 ≤ p 〈 ∞, is not clear. In this paper, we consider the Lp stability of the truncated hierarchical B-spline basis, since the Lp stability is useful for curve and surface fitting, especially for least squares fitting. We prove that this basis is weakly Lp stable. This means that the associated constants to be considered in the stability analysis are at most of polynomial growth in the number of the hierarchy depth. 展开更多
关键词 hierarchical spline space truncated hierarchical B-spline basis stable basis condition number of basis partition of unity
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Analysis of radial basis function interpolation approach 被引量:4
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作者 邹友龙 胡法龙 +3 位作者 周灿灿 李潮流 李长喜 Keh-Jim Dunn 《Applied Geophysics》 SCIE CSCD 2013年第4期397-410,511,共15页
The radial basis function (RBF) interpolation approach proposed by Freedman is used to solve inverse problems encountered in well-logging and other petrophysical issues. The approach is to predict petrophysical prop... The radial basis function (RBF) interpolation approach proposed by Freedman is used to solve inverse problems encountered in well-logging and other petrophysical issues. The approach is to predict petrophysical properties in the laboratory on the basis of physical rock datasets, which include the formation factor, viscosity, permeability, and molecular composition. However, this approach does not consider the effect of spatial distribution of the calibration data on the interpolation result. This study proposes a new RBF interpolation approach based on the Freedman's RBF interpolation approach, by which the unit basis functions are uniformly populated in the space domain. The inverse results of the two approaches are comparatively analyzed by using our datasets. We determine that although the interpolation effects of the two approaches are equivalent, the new approach is more flexible and beneficial for reducing the number of basis functions when the database is large, resulting in simplification of the interpolation function expression. However, the predicted results of the central data are not sufficiently satisfied when the data clusters are far apart. 展开更多
关键词 Inverse problems radial basis function interpolation new approach
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LED用绿色荧光粉BaSi_2N_2O_2:Eu^(2+)的发光和封装性能 被引量:6
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作者 王灵利 倪海勇 张秋红 《发光学报》 EI CAS CSCD 北大核心 2012年第5期465-469,共5页
采用高温固相法合成了白光LED用蓝绿色荧光材料BaSi2N2O2∶Eu2+。用X射线衍射(XRD)、光致发光(PL)等对荧光材料进行了表征。XRD结果表明,所制备的样品为较好的单相。BaSi2N2O2∶Eu2+在395 nm和460 nm激发下均具有较高的发射强度,发射峰... 采用高温固相法合成了白光LED用蓝绿色荧光材料BaSi2N2O2∶Eu2+。用X射线衍射(XRD)、光致发光(PL)等对荧光材料进行了表征。XRD结果表明,所制备的样品为较好的单相。BaSi2N2O2∶Eu2+在395 nm和460 nm激发下均具有较高的发射强度,发射峰位于492 nm附近。当Eu2+的摩尔分数为4%时,可以获得最佳的样品发光强度。将荧光材料封装在紫外和蓝光芯片上制作了LED器件,两种器件均发射出强的蓝绿色荧光,色坐标分别为(0.092 0,0.428 2)和(0.112 9,0.223 0)。 展开更多
关键词 LED 荧光粉 氮氧化物 basi2N2O2∶Eu2+
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新型半导体材料BaSi_2的研究进展 被引量:3
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作者 郝正同 杨子义 谢泉 《材料导报》 EI CAS CSCD 北大核心 2009年第19期28-31,40,共5页
正交相BaSi2是一种新型高效的环境友好半导体材料,在光电、热电方面有着极为广阔的应用前景。详细介绍了正交相BaSi2的结构、光电性质、热电性质及其制备技术,并对目前存在的问题及未来的研究动向作了简要讨论。
关键词 正交相basi2 光电性质 热电性质 晶体结构 制备工艺
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正交相BaSi_2薄膜的制备及结晶研究 被引量:1
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作者 杨子义 郝正同 徐虎 《材料导报》 EI CAS CSCD 北大核心 2014年第10期38-41,共4页
室温下采用磁控溅射的方法在p-Si(111)衬底上沉积Ba膜,然后置入高真空退火炉中在400~850℃退火12 h生成Ba的硅化物薄膜,对退火后的Ba-Si化合物进行了晶体结构、表面形貌、透射光谱及电学性质的测试分析,研究了退火温度对薄膜结晶的... 室温下采用磁控溅射的方法在p-Si(111)衬底上沉积Ba膜,然后置入高真空退火炉中在400~850℃退火12 h生成Ba的硅化物薄膜,对退火后的Ba-Si化合物进行了晶体结构、表面形貌、透射光谱及电学性质的测试分析,研究了退火温度对薄膜结晶的影响。实验结果表明,退火温度对生成Ba-Si化合物及薄膜的表面形貌影响很大,随着退火温度从400℃升高到800℃,薄膜的结晶情况逐渐改善,晶粒随着温度的升高逐渐增大;800℃对于生成多晶的BaSi2薄膜是一个比较理想的退火温度;850℃生成了多相共生的硅化物薄膜。 展开更多
关键词 basi2薄膜 晶体结构 表面形貌 透射光谱 电学性质
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BaSi_2晶体结构及X射线衍射谱的研究 被引量:1
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作者 郝正同 谢泉 杨子义 《功能材料》 EI CAS CSCD 北大核心 2010年第10期1816-1819,共4页
基于汤姆逊弹性散射理论导出了计算衍射峰强度的具体表达式,计算并得到了BaSi2粉晶的X射线衍射谱图,研究了影响粉晶X射线衍射谱线位置、强度和形状的因素。给出了校验及修正粉晶衍射谱图的可靠方法。
关键词 basi2 晶体结构 X射线衍射 衍射强度 布拉格角
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正交相BaSi_2粉晶X射线衍射谱的计算 被引量:1
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作者 杨子义 郝正同 谢泉 《材料导报》 EI CAS CSCD 北大核心 2010年第4期72-74,89,共4页
由正交相BaSi2晶胞原子的分数坐标和散射因子计算出其粉晶X射线衍射谱,结果与PDF卡片的数据相当一致。该计算方法既可用于新材料PDF卡片的计算,也可用于校验实验方法得到的PDF卡片的可靠性。
关键词 正交相basi2 分数坐标 原子散射因子 粉晶 X射线衍射谱
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