期刊文献+
共找到926篇文章
< 1 2 47 >
每页显示 20 50 100
Oscillation of Systems of Parabolic Differential Equations with Deviating Arguments 被引量:1
1
作者 邓立虎 王宏洲 葛渭高 《Journal of Beijing Institute of Technology》 EI CAS 2001年第1期12-16,共5页
To study a class of boundary value problems of parabolic differential equations with deviating arguments, averaging technique, Green’s formula and symbol function sign(·) are used. The multi dimensional problem... To study a class of boundary value problems of parabolic differential equations with deviating arguments, averaging technique, Green’s formula and symbol function sign(·) are used. The multi dimensional problem was reduced to a one dimensional oscillation problem for ordinary differential equations or inequalities. Two oscillatory criteria of solutions for systems of parabolic differential equations with deviating arguments are obtained. 展开更多
关键词 systems of parabolic differential equations boundary value problem deviating arguments OSCILLATION
下载PDF
On a Class of Second Order Differential Inequality with Continuous Distributed Deviating Arguments
2
作者 王培光 葛渭高 《Journal of Beijing Institute of Technology》 EI CAS 1999年第4期337-341,共5页
Aim To study properties of solutions to a class of second order differential inequality with continuous distributed deviating arguments. Methods A direct analysis technique was used. Results and Conclusion Some suf... Aim To study properties of solutions to a class of second order differential inequality with continuous distributed deviating arguments. Methods A direct analysis technique was used. Results and Conclusion Some sufficient conditions that ensure a class of second order delay differential inequality having no eventually positive solutions were obtained, which generalized some given results. Using the results, some oscillatory criteria for solutions of the hyperbolic equation with distributed deviating arguments can be established. 展开更多
关键词 INEQUALITY distributed deviating arguments positive solution
下载PDF
Periodic Solutions of Mixed Type p-Laplacian Equations with Deviating Arguments 被引量:5
3
作者 WANG Xiao-ming 《Chinese Quarterly Journal of Mathematics》 CSCD 2012年第2期177-182,共6页
Based on Mansevich-Mawhin continuation theorem and some analysis skill,some sufficient conditions for the existence of periodic solutions for mixed type p-Laplacian equation with deviating arguments are established,... Based on Mansevich-Mawhin continuation theorem and some analysis skill,some sufficient conditions for the existence of periodic solutions for mixed type p-Laplacian equation with deviating arguments are established,which are complement of previously known results. 展开更多
关键词 P-LAPLACIAN periodic solutions mixed type deviating argument Man’asevichMawhin continuation theorem
下载PDF
The Existence and Uniqueness of Periodic Solutions for a Kind of Lienard Equation with a Deviating Argument 被引量:2
4
作者 WANG Na 《Chinese Quarterly Journal of Mathematics》 CSCD 2010年第1期74-80,共7页
By means of Mawhin's continuation theorem,we study a kind of lie'nard functional differential equations:x"(t)+f(x(t))x'(t)+g(t,x(t-τ(t))) = e(t).Some new results on the existence and uniqueness of pe... By means of Mawhin's continuation theorem,we study a kind of lie'nard functional differential equations:x"(t)+f(x(t))x'(t)+g(t,x(t-τ(t))) = e(t).Some new results on the existence and uniqueness of periodic solutions are obtained. 展开更多
关键词 periodic solution deviating argument lie’nard equations continuation theorem
下载PDF
Periodic Solutions for a Kind of Second Order Differential Equation with a Deviating Argument
5
作者 杜波 鲁世平 《Chinese Quarterly Journal of Mathematics》 CSCD 北大核心 2008年第1期28-35,共8页
By using the theory of coincidence degree, we study a kind of periodic solutions to second order differential equation with a deviating argument such as x″(t) + f(x′(t)) + h(x(t))x′(t) + g(x(t - τ... By using the theory of coincidence degree, we study a kind of periodic solutions to second order differential equation with a deviating argument such as x″(t) + f(x′(t)) + h(x(t))x′(t) + g(x(t - τ(t))) ≈ p(t), some sufficient conditions on the existence of periodic solutions are obtained. 展开更多
关键词 deviating argument periodic solution theory of coincidence degree
下载PDF
Periodic Solutions for p-Laplacian Neutral Functional Differential Equation with a Deviating Argument
6
作者 CHEN Wen-bin GA O Fang L U Shi-ping 《Chinese Quarterly Journal of Mathematics》 CSCD 2013年第4期585-591,共7页
In this paper, by using the continuation theorem of coincidence degree theory and some analysis methods, we study a kind of periodic solutions to p-Laplacian neutral functional differential equation with a deviating a... In this paper, by using the continuation theorem of coincidence degree theory and some analysis methods, we study a kind of periodic solutions to p-Laplacian neutral functional differential equation with a deviating argument,some new results on the existence of periodic solutions is obtained. 展开更多
关键词 periodic solution deviating argument coincidence degree
下载PDF
Further Oscillation Results for a Class of Hyperbolic Equations with Continuous Distributed Deviating Arguments
7
作者 ZHANG Meng SONG Guo-hua 《Chinese Quarterly Journal of Mathematics》 CSCD 2012年第1期145-151,共7页
A class of hyperbolic equations with continuous distributed deviating arguments is considered and its oscillation theorems are discussed.These theorems are of higher degree of generality and deal with the cases which ... A class of hyperbolic equations with continuous distributed deviating arguments is considered and its oscillation theorems are discussed.These theorems are of higher degree of generality and deal with the cases which are not covered by the known criteria.Particularly,these criteria extend and unify a number of existing results. 展开更多
关键词 oscillation criteria hyperbolic equations continuous distributed deviating arguments
下载PDF
New Results on Oscillation of even Order Neutral Differential Equations with Deviating Arguments
8
作者 Lianzhong Li Fanwei Meng 《Advances in Pure Mathematics》 2011年第3期49-53,共5页
In this paper, we point out some small mistakes in [6] and revise them, we obtain some new oscillation results for certain even order neutral differential equations with deviating arguments. Our results extend and imp... In this paper, we point out some small mistakes in [6] and revise them, we obtain some new oscillation results for certain even order neutral differential equations with deviating arguments. Our results extend and improve many known oscillation criteria because the article just generalizes Meng and Xu’s results. 展开更多
关键词 OSCILLATION NEUTRAL DIFFERENTIAL EQUATION deviating ARGUMENT
下载PDF
Oscillation of Differential Equations with Deviating Arguments
9
作者 Yong Zhou (Department of Mathematics, Xiangtan University, Xiangtan, 411 105 ) Y. H. Yu (Institute of Applied Mathematics, Academia Sinica, Beijing, 100080) 《数学理论与应用》 1999年第2期116-118,共3页
In this paper we establish new oscillation criteria for all solution of the first order differential equation with deviating argument. Our result can be applied to the case when coefficients and deviating arguments ar... In this paper we establish new oscillation criteria for all solution of the first order differential equation with deviating argument. Our result can be applied to the case when coefficients and deviating arguments are oscillatory and essentially improve the known results in the literature. 展开更多
关键词 OSCILLATION DIFFERENTIAL EQUATION deviating argument.
下载PDF
Periodicity and Stability in Periodic n-Species Lotka-Volterra Competition System with Feedback Controls and Deviating Arguments 被引量:17
10
作者 MengFAN KeWANG +1 位作者 PatriciaJ.Y.WONG RaviP.AGARWAL 《Acta Mathematica Sinica,English Series》 SCIE CSCD 2003年第4期801-822,共22页
By using the method of coincidence degree and Lyapunov functional, a set ofeasily applicable criteria are established for the global existence and global asymptotic stabilityof strictly positive (componentwise) period... By using the method of coincidence degree and Lyapunov functional, a set ofeasily applicable criteria are established for the global existence and global asymptotic stabilityof strictly positive (componentwise) periodic solution of a periodic n-species Lotka-Volterracompetition system with feedback controls and several deviating arguments. The problem considered inthis paper is in many aspects more general and incorporate as special cases various problems whichhave been studied extensively in the literature. Moreover, our new criteria, which improve andgeneralize some well known results, can be easily checked. 展开更多
关键词 strictly positive periodic solutions globally asymptotic stability Lotka-Volterra competition system feedback controls deviating arguments coincidence degree Lyapunov functional
原文传递
Path Planning and Tracking Control for Parking via Soft Actor-Critic Under Non-Ideal Scenarios 被引量:1
11
作者 Xiaolin Tang Yuyou Yang +3 位作者 Teng Liu Xianke Lin Kai Yang Shen Li 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2024年第1期181-195,共15页
Parking in a small parking lot within limited space poses a difficult task. It often leads to deviations between the final parking posture and the target posture. These deviations can lead to partial occupancy of adja... Parking in a small parking lot within limited space poses a difficult task. It often leads to deviations between the final parking posture and the target posture. These deviations can lead to partial occupancy of adjacent parking lots, which poses a safety threat to vehicles parked in these parking lots. However, previous studies have not addressed this issue. In this paper, we aim to evaluate the impact of parking deviation of existing vehicles next to the target parking lot(PDEVNTPL) on the automatic ego vehicle(AEV) parking, in terms of safety, comfort, accuracy, and efficiency of parking. A segmented parking training framework(SPTF) based on soft actor-critic(SAC) is proposed to improve parking performance. In the proposed method, the SAC algorithm incorporates strategy entropy into the objective function, to enable the AEV to learn parking strategies based on a more comprehensive understanding of the environment. Additionally, the SPTF simplifies complex parking tasks to maintain the high performance of deep reinforcement learning(DRL). The experimental results reveal that the PDEVNTPL has a detrimental influence on the AEV parking in terms of safety, accuracy, and comfort, leading to reductions of more than 27%, 54%, and 26%respectively. However, the SAC-based SPTF effectively mitigates this impact, resulting in a considerable increase in the parking success rate from 71% to 93%. Furthermore, the heading angle deviation is significantly reduced from 2.25 degrees to 0.43degrees. 展开更多
关键词 Automatic parking control strategy parking deviation(APS) soft actor-critic(SAC)
下载PDF
Spatiotemporal characteristics of cultivated land use eco-efficiency and its influencing factors in China from 2000 to 2020 被引量:1
12
作者 LI Shaoting MU Na +1 位作者 REN Yanjun Thomas GLAUBEN 《Journal of Arid Land》 SCIE CSCD 2024年第3期396-414,共19页
Improving cultivated land use eco-efficiency(CLUE)can effectively promote agricultural sustainability,particularly in developing countries where CLUE is generally low.This study used provincial-level data from China t... Improving cultivated land use eco-efficiency(CLUE)can effectively promote agricultural sustainability,particularly in developing countries where CLUE is generally low.This study used provincial-level data from China to evaluate the spatiotemporal evolution of CLUE from 2000 to 2020 and identified the influencing factors of CLUE by using a panel Tobit model.In addition,given the undesirable outputs of agricultural production,we incorporated carbon emissions and nonpoint source pollution into the global benchmark-undesirable output-super efficiency-slacks-based measure(GB-US-SBM)model,which combines global benchmark technology,undesirable output,super efficiency,and slacks-based measure.The results indicated that there was an upward trend in CLUE in China from 2000 to 2020,with an increase rate of 2.62%.The temporal evolution of CLUE in China could be classified into three distinct stages:a period of fluctuating decrease(2000-2007),a phase of gradual increase(2008-2014),and a period of rapid growth(2015-2020).The major grain-producing areas(MPAs)had a lower CLUE than their counterparts,namely,non-major grain-production areas(non-MPAs).The spatial agglomeration effect followed a northeast-southwest strip distribution;and the movement path of barycentre revealed a"P"shape,with Luoyang City,Henan Province,as the centre.In terms of influencing factors of CLUE,investment in science and technology played the most vital role in improving CLUE,while irrigation index had the most negative effect.It should be noted that these two influencing factors had different impacts on MPAs and non-MPAs.Therefore,relevant departments should formulate policies to enhance the level of science and technology,improve irrigation condition,and promote sustainable utilization of cultivated land. 展开更多
关键词 cultivated land use eco-efficiency(CLUE) slacks-based measure(SBM)model barycentre model standard deviation ellipse(SDE) panel Tobit model carbon emissions nonpoint source pollution
下载PDF
EXISTENCE AND UNIQUENESS OF ANTI-PERIODIC SOLUTIONS TO AN nTH-ORDER NONLINEAR DIFFERENTIAL EQUATION WITH MULTIPLE DEVIATING ARGUMENTS 被引量:13
13
作者 Jianzhong Xu 1,2,Zongfu Zhou 1 (1.Dept.of Math.,Bozhou Teachers College,Bozhou 236800,Anhui,2.School of Mathematical Sciences,Anhui University,Hefei 230039) 《Annals of Differential Equations》 2012年第1期105-114,共10页
In this paper,we use the Leray-Schauder degree theory to establish some new results on the existence and uniqueness of anti-periodic solutions to an nth-order nonlinear differential equation with multiple deviating ar... In this paper,we use the Leray-Schauder degree theory to establish some new results on the existence and uniqueness of anti-periodic solutions to an nth-order nonlinear differential equation with multiple deviating arguments. 展开更多
关键词 anti-periodic solution Leray-Schauder degree deviating arguments continuation theorem
原文传递
OSCILLATORY AND ASYMPTOTIC BEHAVIOR OF FIRST ORDER DIFFERENTIAL EQUATION WITH PIECEWISE CONSTANT DEVIATING ARGUMENTS 被引量:4
14
作者 冯月才 戴运恩 《Annals of Differential Equations》 1999年第4期345-351,共7页
In this paper, we consider the oscillatory and asymptotic behavior of solu-tions of first order nonlinear neutral differential equation with piecewise constantdeviating arguments. Several criteria are obtained for osc... In this paper, we consider the oscillatory and asymptotic behavior of solu-tions of first order nonlinear neutral differential equation with piecewise constantdeviating arguments. Several criteria are obtained for oscillatory and asymptoticbehavior of solutions of the equation. 展开更多
关键词 PIECEWISE CONSTANT deviating arguments neutral differential equa-tion OSCILLATORY BEHAVIOR asymptotic BEHAVIOR
原文传递
PERIODIC SOLUTION FOR p-LAPLACIAN DIFFERENTIAL EQUATION WITH A DEVIATING ARGUMENT 被引量:5
15
作者 Zhu Yanling Lu Shiping 《Annals of Differential Equations》 2007年第1期119-126,共8页
By using the theory of coincidence degree, we study a kind of periodic solution to p-Laplacian differential equation with a deviating argument such as (φp(x'(t)))' + f(x(t)) + g(x(t - τ(t))) = e... By using the theory of coincidence degree, we study a kind of periodic solution to p-Laplacian differential equation with a deviating argument such as (φp(x'(t)))' + f(x(t)) + g(x(t - τ(t))) = e(t), a result on the existence of periodic solution is obtained. 展开更多
关键词 deviating argument periodic solution theory of coincidence degree
原文传递
A Distortion Self-Calibration Method for Binocular High Dynamic Light Adjusting and Imaging System Based on Digital Micromirror Device
16
作者 Pei Wu Yanjie Wang +1 位作者 Honghai Sun Zhuoman Wen 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2024年第9期2036-2038,共3页
Dear Editor,In order to realize the pixel level light adjusting control of the binocular high dynamic light adjusting and imaging system, this letter proposed a novel self-calibration method. By analyzing the optical ... Dear Editor,In order to realize the pixel level light adjusting control of the binocular high dynamic light adjusting and imaging system, this letter proposed a novel self-calibration method. By analyzing the optical design of the system, the causes of the distortion are given and a distortion model is established. Then, a quick and accurate self-calibration method is designed. The experiments indicate that the method can calibrate the two image sensors of the system at the same time,the average pixel deviation of the calibrated system is less than 0.5pixels and the maximum deviation is less than 1 pixel. 展开更多
关键词 DYNAMIC system deviation
下载PDF
Spatiotemporal patterns and drivers of cultivated land conversion in Inner Mongolia Autonomous Region,northern China
17
作者 Xijiri ZHOU Ruiping +1 位作者 BAO Baorong Burenjirigala 《Journal of Arid Land》 SCIE CSCD 2024年第9期1197-1213,共17页
Protection and optimization of cultivated land resources are of great significance to national food security.Cultivated land conversion in northern China has increased in recent years due to the industrialization and ... Protection and optimization of cultivated land resources are of great significance to national food security.Cultivated land conversion in northern China has increased in recent years due to the industrialization and urbanization of society.However,the assessment of cultivated land conversion in this area is insufficient,posing a potential risk to cultivated land resources.This study evaluated the evolution and spatiotemporal patterns of cultivated land conversion in Inner Mongolia Autonomous Region,China,and the driving factors to improve rational utilization and to protect cultivated land resources.The spatiotemporal patterns of cultivated land conversion in Inner Mongolia were analyzed using the cultivated land conversion index,kernel density analysis,a standard deviation ellipse model,and a geographic detector.Results showed that from 2000 to 2020,the trends in cultivated land conversion area and rate in Inner Mongolia exhibited fluctuating growth,with the total area of cultivated land conversion reaching 7307.59 km^(2) at a rate of 6.69%.Spatial distribution of cultivated land conversion was primarily concentrated in the Hetao Plain,Nengjiang Plain,Liaohe Plain,and the Hohhot-Baotou-Ordos urban agglomeration.Moreover,the standard deviational ellipse of cultivated land conversion in Inner Mongolia exhibited a directional southwest-northeast-southwest-northeast distribution,with the northeast-southwest direction identified as the main driving force of spatial change in cultivated land conversion.Meanwhile,cultivated land conversion exhibited an increase-decrease-increase change process,indicating that spatial distribution of cultivated land conversion in Inner Mongolia became gradually apparent within the study period.The geographic detector results further revealed that the main driving factors of cultivated land conversion in Inner Mongolia were the share of secondary and tertiary industries and per-unit area yield of grain,with explanatory rates of 57.00%,55.00%,and 51.00%,respectively.Additionally,improved agricultural production efficiency and the coordinated development of population urbanization and industry resulted in cultivated land conversion.Collectively,the findings of this study indicated that,from 2000 to 2020,the cultivated land conversion in Inner Mongolia was significant and fluctuated in time,and had strong spatial heterogeneity.The primary drivers of these events included the effects of agriculture,population,and social economy. 展开更多
关键词 cultivated land conversion spatiotemporal variation standard deviation elliptical models geographic detector northern China
下载PDF
OSCILLATION CRITERIA FOR HIGHER-ORDER IMPULSIVE HYPERBOLIC SYSTEM WITH DISTRIBUTED DEVIATING ARGUMENTS 被引量:1
18
作者 Zhu Xianyang Li Yongkun Lu Linghong 《Annals of Differential Equations》 2006年第1期119-126,共8页
By the methods of differential inequality and eigenvalue, we obtain several sufficient conditions for oscillation of solutions for higher-order impulsive hyperbolic system with distributed deviating arguments under Ro... By the methods of differential inequality and eigenvalue, we obtain several sufficient conditions for oscillation of solutions for higher-order impulsive hyperbolic system with distributed deviating arguments under Robin and Dirichlet boundary value conditions. 展开更多
关键词 OSCILLATION hyperbolic system IMPULSIVE distributed deviating arguments
原文传递
Computing large deviation prefactors of stochastic dynamical systems based on machine learning
19
作者 李扬 袁胜兰 +1 位作者 陆凌宏志 刘先斌 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第4期364-373,共10页
We present a large deviation theory that characterizes the exponential estimate for rare events in stochastic dynamical systems in the limit of weak noise.We aim to consider a next-to-leading-order approximation for m... We present a large deviation theory that characterizes the exponential estimate for rare events in stochastic dynamical systems in the limit of weak noise.We aim to consider a next-to-leading-order approximation for more accurate calculation of the mean exit time by computing large deviation prefactors with the aid of machine learning.More specifically,we design a neural network framework to compute quasipotential,most probable paths and prefactors based on the orthogonal decomposition of a vector field.We corroborate the higher effectiveness and accuracy of our algorithm with two toy models.Numerical experiments demonstrate its powerful functionality in exploring the internal mechanism of rare events triggered by weak random fluctuations. 展开更多
关键词 machine learning large deviation prefactors stochastic dynamical systems rare events
下载PDF
ASYMPTOTIC BEHAVIOR OF HIGHER ORDER NONLINEAR INTEGRO-DIFFERENTIAL EQUATIONS WITH DEVIATING ARGUMENTS 被引量:1
20
作者 Jianli Yao Fanwei Meng Fengying Wang 《Annals of Differential Equations》 2013年第4期474-483,共10页
In this paper, we study a class of higher order nonlinear integro-diferential equations with deviating arguments. With the aid of the integral inequality, we obtain some sufcient conditions under which all solutions t... In this paper, we study a class of higher order nonlinear integro-diferential equations with deviating arguments. With the aid of the integral inequality, we obtain some sufcient conditions under which all solutions to the equation have some asymptotic behavior. 展开更多
关键词 integro-diferential equations with deviating argument asymptotic behavior of solutions integral inequality
原文传递
上一页 1 2 47 下一页 到第
使用帮助 返回顶部