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京津冀地区碳排放时空格局变化及其驱动因子 被引量:2
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作者 陈靖松 张建军 +1 位作者 李金龙 李山 《生态学报》 CAS CSCD 北大核心 2024年第6期2270-2283,共14页
人类对陆地生态系统的改变是碳排放增加的主要原因。在“双碳”目标背景下探索土地利用变化与碳排放的动态关系,有助于区域土地低碳可持续利用。研究基于土地利用转移视角,采用重心-标准差椭圆方法揭示了京津冀地区土地利用碳排放时空... 人类对陆地生态系统的改变是碳排放增加的主要原因。在“双碳”目标背景下探索土地利用变化与碳排放的动态关系,有助于区域土地低碳可持续利用。研究基于土地利用转移视角,采用重心-标准差椭圆方法揭示了京津冀地区土地利用碳排放时空格局演化特征,评估了碳排放与生态环境、社会经济发展的协调程度,并借助改进的Kaya模型和LMDI分解模型定量分析了土地利用变化对碳排放的影响程度。结果表明:(1)建设用地的转入是土地利用碳排放增加的主要来源,引起碳排放量增加15844.36万t;耕地、草地向林地、水域的转变促进了地区固碳能力的提升。(2)土地利用碳排放空间分布格局呈现出东北-西南方向向中心进一步聚集的趋势,并且东-西向聚集趋势大于南-北向。(3)京津冀地区整体碳排放与生态环境的协调性呈向好趋势发展,但大部分地区碳排放与社会经济发展出现失衡现象,地区间碳生产力差异逐渐增大。(4)经济水平是促进碳排放增加的最显著因素,单位GDP用地强度是抑制碳排放增加的最主要因素。分析结果表明,严格控制建设用地的无序扩张是促进低碳土地利用的基础,低碳经济发展是促进地区减碳的重要途径。 展开更多
关键词 城市群 土地利用 碳排放 Logarithmic Mean Divisia Index
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细菌型豆豉热风干燥特性及干燥模型
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作者 孟淑真 马飞 +1 位作者 吴拥军 李升 《中国食物与营养》 2024年第3期27-35,共9页
目的:提高细菌型豆豉热风干燥加工效率和控制干燥过程。方法:研究干燥风温、风速和铺放厚度对细菌型豆豉干燥特性的影响,选用8种经典干燥模型对实验数据进行非线性拟合,以决定系数(R^(2))、卡方(χ^(2))、均方根误差(RMSE)为评价指标筛... 目的:提高细菌型豆豉热风干燥加工效率和控制干燥过程。方法:研究干燥风温、风速和铺放厚度对细菌型豆豉干燥特性的影响,选用8种经典干燥模型对实验数据进行非线性拟合,以决定系数(R^(2))、卡方(χ^(2))、均方根误差(RMSE)为评价指标筛选得到最适干燥模型,并对模型参数进行回归分析,得到最适干燥模型拟合方程。结果:细菌型豆豉热风干燥过程属于降速干燥;相比于风温和风速,铺放厚度对豆豉的有效水分扩散系数影响最大;干燥活化能为20.588 kJ/mol,较易于干燥。Logarithmic模型为该豆豉热风干燥的最适模型,此模型拟合方程能较准确反应豆豉干燥过程中水分比变化情况。结论:研究结果为工业生产细菌型干豆豉提供科学依据。 展开更多
关键词 细菌型豆豉 热风干燥 干燥特性 Logarithmic模型
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Time-domain dynamic constitutive model suitable for mucky soil site seismic response 被引量:1
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作者 Dong Qing Chen Su +2 位作者 Jin Liguo Zhou Zhenghua Li Xiaojun 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2024年第1期1-13,共13页
Soil nonlinear behavior displays noticeable effects on the site seismic response.This study proposes a new functional expression of the skeleton curve to replace the hyperbolic skeleton curve.By integrating shear modu... Soil nonlinear behavior displays noticeable effects on the site seismic response.This study proposes a new functional expression of the skeleton curve to replace the hyperbolic skeleton curve.By integrating shear modulus and combining the dynamic skeleton curve and the damping degradation coefficient,the constitutive equation of the logarithmic dynamic skeleton can be obtained,which considers the damping effect in a soil dynamics problem.Based on the finite difference method and the multi-transmitting boundary condition,a 1D site seismic response analysis program called Soilresp1D has been developed herein and used to analyze the time-domain seismic response in three types of sites.At the same time,this study also provides numerical simulation results based on the hyperbolic constitutive model and the equivalent linear method.The results verify the rationality of the new soil dynamic constitutive model.It can analyze the mucky soil site nonlinear seismic response,reflecting the deformation characteristics and damping effect of the silty soil.The hysteresis loop area is more extensive,and the residual strain is evident. 展开更多
关键词 seismic response time-domain dynamic constitutive model logarithmic dynamic skeleton dampening effect mucky soil
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Quantum correlations and entanglement in coupled optomechanical resonators with photon hopping via Gaussian interferometric power analysis
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作者 Y.Lahlou B.Maroufi M.Daoud 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第5期204-211,共8页
Quantum correlations that surpass entanglement are of great importance in the realms of quantum information processing and quantum computation.Essentially,for quantum systems prepared in pure states,it is difficult to... Quantum correlations that surpass entanglement are of great importance in the realms of quantum information processing and quantum computation.Essentially,for quantum systems prepared in pure states,it is difficult to differentiate between quantum entanglement and quantum correlation.Nonetheless,this indistinguishability is no longer holds for mixed states.To contribute to a better understanding of this differentiation,we have explored a simple model for both generating and measuring these quantum correlations.Our study concerns two macroscopic mechanical resonators placed in separate Fabry–Pérot cavities,coupled through the photon hopping process.this system offers a comprehensively way to investigate and quantify quantum correlations beyond entanglement between these mechanical modes.The key ingredient in analyzing quantum correlation in this system is the global covariance matrix.It forms the basis for computing two essential metrics:the logarithmic negativity(E_(N)^(m))and the Gaussian interferometric power(P_(G)^(m)).These metrics provide the tools to measure the degree of quantum entanglement and quantum correlations,respectively.Our study reveals that the Gaussian interferometric power(P_(G)^(m))proves to be a more suitable metric for characterizing quantum correlations among the mechanical modes in an optomechanical quantum system,particularly in scenarios featuring resilient photon hopping. 展开更多
关键词 quantum correlations ENTANGLEMENT Gaussian interferometric power logarithmic negativity optomechanics photon hopping
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Higher-order expansions of powered extremes of logarithmic general error distribution
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作者 TAN Xiao-feng LI Li-hui 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2024年第1期47-54,共8页
In this paper,Let M_(n)denote the maximum of logarithmic general error distribution with parameter v≥1.Higher-order expansions for distributions of powered extremes M_(n)^(p)are derived under an optimal choice of nor... In this paper,Let M_(n)denote the maximum of logarithmic general error distribution with parameter v≥1.Higher-order expansions for distributions of powered extremes M_(n)^(p)are derived under an optimal choice of normalizing constants.It is shown that M_(n)^(p),when v=1,converges to the Frechet extreme value distribution at the rate of 1/n,and if v>1 then M_(n)^(p)converges to the Gumbel extreme value distribution at the rate of(loglogn)^(2)=(log n)^(1-1/v). 展开更多
关键词 logarithmic general error distribution convergence rate higher-order expansion powered ex-treme
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芒果切片热风干燥特性及模型
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作者 黄敏 甘婷 +2 位作者 易萍 黄方 李丽 《食品与机械》 CSCD 北大核心 2024年第4期179-186,209,共9页
目的:为对芒果热风干燥过程进行预测与控制。方法:以新鲜金煌芒为试验材料,研究热风温度(60,65,70℃)和芒果切片厚度(0.8,1.0,1.2 cm)对芒果热风干燥曲线、干燥特性曲线、水分有效扩散系数等的影响,并选取常用的适用于果蔬的6种干燥模... 目的:为对芒果热风干燥过程进行预测与控制。方法:以新鲜金煌芒为试验材料,研究热风温度(60,65,70℃)和芒果切片厚度(0.8,1.0,1.2 cm)对芒果热风干燥曲线、干燥特性曲线、水分有效扩散系数等的影响,并选取常用的适用于果蔬的6种干燥模型进行拟合、分析及验证,选出最适合芒果热风干燥的模型。结果:随温度的升高,切片厚度的减小,加快了芒果片的干燥速率,所需的干燥时间越短。水分有效扩散系数随温度和厚度的增大而增大,为1.40139×10^(-10)~3.65546×10^(-10)m^(2)/s。Logarithmic模型的R^(2)最大、X^(2)和RMSE最小,分别为0.99887,0.000124779,0.00137。结论:Logarithmic模型预测值与试验值验证基本吻合,可以较好反映芒果片在干燥过程中水分含量的变化规律。 展开更多
关键词 芒果 热风干燥 干燥特性 干燥模型 Logarithmic模型
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THE LOGARITHMIC SOBOLEV INEQUALITY FOR A SUBMANIFOLD IN MANIFOLDS WITH ASYMPTOTICALLY NONNEGATIVE SECTIONAL CURVATURE
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作者 东瑜昕 林和子 陆琳根 《Acta Mathematica Scientia》 SCIE CSCD 2024年第1期189-194,共6页
In this note,we prove a logarithmic Sobolev inequality which holds for compact submanifolds without a boundary in manifolds with asymptotically nonnegative sectional curvature.Like the Michale-Simon Sobolev inequality... In this note,we prove a logarithmic Sobolev inequality which holds for compact submanifolds without a boundary in manifolds with asymptotically nonnegative sectional curvature.Like the Michale-Simon Sobolev inequality,this inequality contains a term involving the mean curvature. 展开更多
关键词 asymptotically nonnegative sectional curvature logarithmic Sobolev inequality ABP method
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Radial solution of the Logarithmic Laplacian system
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作者 ZHANG Li-hong NIE Xiao-feng +1 位作者 WANG Guo-tao Bashir Ahmad 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2024年第1期114-124,共11页
The paper generalizes the direct method of moving planes to the Logarithmic Laplacian system.Firstly,some key ingredients of the method are discussed,for example,Narrow region principle and Decay at infinity.Then,the ... The paper generalizes the direct method of moving planes to the Logarithmic Laplacian system.Firstly,some key ingredients of the method are discussed,for example,Narrow region principle and Decay at infinity.Then,the radial symmetry of the solution of the Logarithmic Laplacian system is obtained. 展开更多
关键词 the Logarithmic Laplacian system radial symmetry the direct method of moving planes
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Global Existence and Decay of Solutions for a Class of a Pseudo-Parabolic Equation with Singular Potential and Logarithmic Nonlocal Source
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作者 Xiaoxin Yang 《Journal of Applied Mathematics and Physics》 2024年第1期181-193,共13页
This article investigates the well posedness and asymptotic behavior of Neumann initial boundary value problems for a class of pseudo-parabolic equations with singular potential and logarithmic nonlinearity. By utiliz... This article investigates the well posedness and asymptotic behavior of Neumann initial boundary value problems for a class of pseudo-parabolic equations with singular potential and logarithmic nonlinearity. By utilizing cut-off techniques and combining with the Faedo Galerkin approximation method, local solvability was established. Based on the potential well method and Hardy Sobolev inequality, derive the global existence of the solution. In addition, we also obtained the results of decay. 展开更多
关键词 Nonlocal Parabolic Equation Singular Potential Logarithmic Nonlocal Source Global Existence DECAY
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Global Existence of the Solution for a Reduced Model of the Vectorial Quantum Zakharov System
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作者 Guiyu Yang 《Journal of Applied Mathematics and Physics》 2024年第2期533-542,共10页
In this paper, we study the global existence of the smooth solution for a reduced quantum Zakharov system in two spatial dimensions. Using energy estimates and the logarithmic type Sobolev inequality, we show the glob... In this paper, we study the global existence of the smooth solution for a reduced quantum Zakharov system in two spatial dimensions. Using energy estimates and the logarithmic type Sobolev inequality, we show the global existence of the solution to this system without any small condition on the initial data. 展开更多
关键词 Quantum Zakharov System Global Existence Logarithmic Sobolev Inequality
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Nonlinear Relationship and Its Evolutionary Trace between Node Degree and Average Path Length of China Aviation Network Based on Complex Network
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作者 Cheng Xiangjun Zhang Xiaoxuan Li Yangqi 《Journal of Traffic and Transportation Engineering》 2024年第1期11-22,共12页
In order to reveal the complex network characteristics and evolution principle of China aviation network,the relationship between the node degree and the average path length of China aviation network in 1988,1994,2001... In order to reveal the complex network characteristics and evolution principle of China aviation network,the relationship between the node degree and the average path length of China aviation network in 1988,1994,2001,2008 and 2015 was studied.According to the theory and method of complex network,the network system was constructed with the city where the airport was located as the network node and the airline as the edge of the network.On the basis of the statistical data,the node average path length of China aviation network in 1988,1994,2001,2008 and 2015 was calculated.Through regression analysis,it was found that the node degree had a logarithmic relationship with the average length of node path,and the two parameters of the logarithmic relationship had linear evolutionary trace.Key word:China aviation network,complex network,node degree,average length of node path,logarithmic relationship,evolutionary trace. 展开更多
关键词 China aviation network complex network node degree average length of node path logarithmic relationship evolutionary trace.
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Existence of a Sigh-Changing Solution Result for Logarithmic Schrödinger Equations with Weight Function
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作者 Jingxing Huang Junhui Xie 《Journal of Applied Mathematics and Physics》 2024年第7期2665-2681,共17页
This paper is devoted to studying the existence of solutions for the following logarithmic Schrödinger problem: −div(a(x)∇u)+V(x)u=ulogu2+k(x)| u |q1−2u+h(x)| u |q2−2u,  x∈ℝN.(1)We first prove that the correspon... This paper is devoted to studying the existence of solutions for the following logarithmic Schrödinger problem: −div(a(x)∇u)+V(x)u=ulogu2+k(x)| u |q1−2u+h(x)| u |q2−2u,  x∈ℝN.(1)We first prove that the corresponding functional I belongs to C1(HV1(ℝN),ℝ). Furthermore, by using the variational method, we prove the existence of a sigh-changing solution to problem (1). 展开更多
关键词 Logarithmic Schrödinger Equations Weight Function Constrained Minimization Method Symmetric Mountain Pass Theorem
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Nonlinear Relationship and Its Evolutionary Trace between Average Degree and Average Path Length of Edge Vertices of China Aviation Network Based on Complex Network
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作者 Cheng Xiangjun Chen Xumei Guo Jianyuan 《Journal of Traffic and Transportation Engineering》 2024年第5期224-237,共14页
In order to reveal the complex network characteristics and evolution principle of China aviation network,the relationship between the average degree and the average path length of edge vertices of China aviation netwo... In order to reveal the complex network characteristics and evolution principle of China aviation network,the relationship between the average degree and the average path length of edge vertices of China aviation network in 1988,1994,2001,2008 and 2015 was studied.According to the theory and method of complex network,the network system was constructed with the city where the airport was located as the network node and the airline as the edge of the network.On the basis of the statistical data,the average degree and average path length of edge vertices of China aviation network in 1988,1994,2001,2008 and 2015 were calculated.Through regression analysis,it was found that the average degree had a logarithmic relationship with the average path length of edge vertices and the two parameters of the logarithmic relationship had linear evolutionary trace. 展开更多
关键词 China aviation network complex network average degree of edge vertices average path length of edge vertices logarithmic relationship evolutionary trace
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Vertical deformation model on postseismic phase using exponential and logarithmic function based on InSAR
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作者 Irma Yusiyanti Tattyana Wening Kalbuadi Prajardi +1 位作者 Yofita Indah Saputri Cecep Pratama 《Geodesy and Geodynamics》 EI CSCD 2023年第4期392-400,共9页
The Palu MW7.4 earthquake occurred on September 28, 2018, with the epicenter at 119.86°, 0.72°. The severe shaking caused severe damage in Central Sulawesi, especially in Palu. We conducted a postseismic def... The Palu MW7.4 earthquake occurred on September 28, 2018, with the epicenter at 119.86°, 0.72°. The severe shaking caused severe damage in Central Sulawesi, especially in Palu. We conducted a postseismic deformation study to determine the deformation pattern and reduce future earthquakes’ impact.Interferometric Synthetic Aperture Radar(In SAR) data were processed using Li CSBAS to get the time series. The time series data were fitted to exponential and logarithmic functions to determine the mechanism of postseismic deformation. The exponential model identified the influence of the viscoelastic mechanism, and the logarithm identified the afterslip mechanism. The Palu earthquake was fitted to logarithmic and exponential, but the logarithmic was more significant than an exponential function.Afterslip mechanism predominates, and viscoelastic mechanisms play a minor role in this postseismic deformation. 展开更多
关键词 EARTHQUAKE DEFORMATION POSTSEISMIC Physical mechanism EXPONENTIAL Logarithmic
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Exact simulation for direction-dependent large elastic strain responses of soft fibre-reinforced composites
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作者 Huifeng XI Guicheng ZHAO +2 位作者 OBRUHNS Siyu WANG Heng XIAO 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2023年第9期1497-1510,共14页
An explicit form of the elastic strain-energy function for direction-dependent large elastic strain behaviors of soft fiber-reinforced composites is first presented based upon a decoupled approach for simulating compl... An explicit form of the elastic strain-energy function for direction-dependent large elastic strain behaviors of soft fiber-reinforced composites is first presented based upon a decoupled approach for simulating complex nonlinear coupling effects.From this form,the exact closed-form solutions are then obtained for the uniaxial tension responses in the fiber and cross-fiber directions.With such exact solutions,the issue of simultaneously simulating strongly coupling nonlinear responses in the fiber and cross-fiber directions may be reduced to the issue of separately treating each decoupled uniaxial stress-strain response,thus bypassing usual complexities and uncertainties involved in identifying a large number of strongly coupled adjustable parameters.The numerical examples given are in good agreement with the experimental data for large strain responses. 展开更多
关键词 soft solid fiber-reinforced composite large elastic strain transverse isotropy strain-energy function logarithmic strain decoupling approach
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A higher-order porous thermoelastic problem with microtemperatures
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作者 J.R.FERNáNDEZ R.QUINTANILLA 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2023年第11期1911-1926,共16页
In this paper,we study a porous thermoelastic problem with microtemperatures assuming parabolic higher order in time derivatives for the thermal variables.The model is derived and written as a coupled linear system.Th... In this paper,we study a porous thermoelastic problem with microtemperatures assuming parabolic higher order in time derivatives for the thermal variables.The model is derived and written as a coupled linear system.Then,a uniqueness result is proved by using the logarithmic convexity method in the case that we do not assume that the mechanical energy is positive definite.Finally,the existence of the solution is obtained by introducing an energy function and applying the theory of linear semigroups. 展开更多
关键词 higher order THERMOELASTICITY microtemperature logarithmic convexity method existence and uniqueness
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CLOSURE OF ANALYTIC FUNCTIONS OF THE BOUNDED MEAN OSCILLATION IN LOGARITHMIC BLOCH SPACES
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作者 叶善力 周智慧 《Acta Mathematica Scientia》 SCIE CSCD 2023年第1期43-50,共8页
For anyα∈R,the logarithmic Bloch space BLαconsists of those functions f which are analytic in the unit disk D with.■In this paper,we characterize the closure of the analytic functions of bounded mean oscillation B... For anyα∈R,the logarithmic Bloch space BLαconsists of those functions f which are analytic in the unit disk D with.■In this paper,we characterize the closure of the analytic functions of bounded mean oscillation BMOA in the logarithmic Bloch space BLαfor allα∈R. 展开更多
关键词 CLOSURE logarithmic Bloch spaces BMOA
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Constructing Representative Collective Signature Protocols Using The GOST R34.10-1994 Standard
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作者 Tuan Nguyen Kim Duy Ho Ngoc Nikolay A.Moldovyan 《Computers, Materials & Continua》 SCIE EI 2023年第1期1475-1491,共17页
The representative collective digital signature,which was suggested by us,is built based on combining the advantages of group digital signature and collective digital signature.This collective digital signature schema... The representative collective digital signature,which was suggested by us,is built based on combining the advantages of group digital signature and collective digital signature.This collective digital signature schema helps to create a unique digital signature that deputizes a collective of people representing different groups of signers and may also include personal signers.The advantage of the proposed collective signature is that it can be built based on most of the well-known difficult problems such as the factor analysis,the discrete logarithm and finding modulo roots of large prime numbers and the current digital signature standards of the United States and Russian Federation.In this paper,we use the discrete logarithmic problem on prime finite fields,which has been implemented in the GOST R34.10-1994 digital signature standard,to build the proposed collective signature protocols.These protocols help to create collective signatures:Guaranteed internal integrity and fixed size,independent of the number of members involved in forming the signature.The signature built in this study,consisting of 3 components(U,R,S),stores the information of all relevant signers in the U components,thus tracking the signer and against the“disclaim of liability”of the signer later is possible.The idea of hiding the signer’s public key is also applied in the proposed protocols.This makes it easy for the signing group representative to specify which members are authorized to participate in the signature creation process. 展开更多
关键词 Signing collective signing group discrete logarithm group signature collective signature GOST standards
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THE LAW OF THE ITERATED LOGARITHM FOR SPATIAL AVERAGES OF THE STOCHASTIC HEAT EQUATION
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作者 李精玉 张勇 《Acta Mathematica Scientia》 SCIE CSCD 2023年第2期907-918,共12页
Let u(t,x)be the solution to the one-dimensional nonlinear stochastic heat equation driven by space-time white noise with u(0,x)=1 for all x∈R.In this paper,we prove the law of the iterated logarithm(LIL for short)an... Let u(t,x)be the solution to the one-dimensional nonlinear stochastic heat equation driven by space-time white noise with u(0,x)=1 for all x∈R.In this paper,we prove the law of the iterated logarithm(LIL for short)and the functional LIL for a linear additive functional of the form∫[0,R]u(t,x)dx and the nonlinear additive functionals of the form∫[0,R]g(u(t,x))dx,where g:R→R is nonrandom and Lipschitz continuous,as R→∞for fixed t>0,using the localization argument. 展开更多
关键词 law of the iterated logarithm stochastic heat equation Malliavin calculus
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Nyström kernel algorithm based on least logarithmic hyperbolic cosine loss
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作者 Shen-Jie Tang Yu Tang +6 位作者 Xi-Feng Li Bo Liu Dong-Jie Bi Guo Yi Xue-Peng Zheng Li-Biao Peng Yong-Le Xie 《Journal of Electronic Science and Technology》 EI CAS CSCD 2023年第3期82-93,共12页
Kernel adaptive filters(KAFs)have sparked substantial attraction for online non-linear learning applications.It is noted that the effectiveness of KAFs is highly reliant on a rational learning criterion.Concerning thi... Kernel adaptive filters(KAFs)have sparked substantial attraction for online non-linear learning applications.It is noted that the effectiveness of KAFs is highly reliant on a rational learning criterion.Concerning this,the logarithmic hyperbolic cosine(lncosh)criterion with better robustness and convergence has drawn attention in recent studies.However,existing lncosh loss-based KAFs use the stochastic gradient descent(SGD)for optimization,which lack a trade-off between the convergence speed and accuracy.But recursion-based KAFs can provide more effective filtering performance.Therefore,a Nyström method-based robust sparse kernel recursive least lncosh loss algorithm is derived in this article.Experiments via measures and synthetic data against the non-Gaussian noise confirm the superiority with regard to the robustness,accuracy performance,and computational cost. 展开更多
关键词 Kernel adaptive filter(KAF) logarithmic hyperbolic cosine (lncosh)loss Nyström method RECURSIVE
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