期刊文献+
共找到21篇文章
< 1 2 >
每页显示 20 50 100
Necessary and Sufficient Conditions in Smooth Programming with Generalized Convexity 被引量:1
1
作者 孙清滢 叶留青 《Chinese Quarterly Journal of Mathematics》 CSCD 2000年第4期33-37,共5页
Hanson and Mond have grven sets of necessary and sufficient conditions for optimality in constrained optimization by introducing classes of generalized functions, called type Ⅰ functions. Recently, Bector definded un... Hanson and Mond have grven sets of necessary and sufficient conditions for optimality in constrained optimization by introducing classes of generalized functions, called type Ⅰ functions. Recently, Bector definded univex functions, a new class of functions that unifies several concepts of generalized convexity. In this paper, additional conditions are attached to the Kuhn Tucker conditions giving a set of conditions which are both necessary and sufficient for optimality in constrained optimization, under appropriate constraint qualifications. 展开更多
关键词 necessary and sufficient conditions generalized convexity nonlinear programming multiobjective programming type functions
在线阅读 下载PDF
ON THE NECESSARY AND SUFFICIENT CONDITIONS TO SOLVE A HEAT EQUATION WITH GENERAL ADDITIVE GAUSSIAN NOISE 被引量:2
2
作者 Yaozhong HU Yanghui LIU 《Acta Mathematica Scientia》 SCIE CSCD 2019年第3期669-690,共22页
In this note, we consider stochastic heat equation with general additive Gaussian noise. Our aim is to derive some necessary and sufficient conditions on the Gaussian noise in order to solve the corresponding heat equ... In this note, we consider stochastic heat equation with general additive Gaussian noise. Our aim is to derive some necessary and sufficient conditions on the Gaussian noise in order to solve the corresponding heat equation. We investigate this problem invoking two differen t met hods, respectively, based on variance compu tations and on pat h-wise considerations in Besov spaces. We are going to see that, as anticipated, both approaches lead to the same necessary and sufficient condition on the noise. In addition, the path-wise approach brings out regularity results for the solution. 展开更多
关键词 Stochastic heat equation general Gaussian noise L^(2) solution sufficient and necessary condition Wong-Zakai approximation pathwise solution Holder continuity Besov space
在线阅读 下载PDF
NECESSARY AND SUFFICIENT CONDITIONS OF EXISTENCE AND UNIQUENESS OF LIMIT CYCLES FOR A CLASS OF POLYNOMIAL SYSTEM 被引量:1
3
作者 刘德明 《Acta Mathematica Scientia》 SCIE CSCD 1991年第1期65-71,共7页
In this paper, we discuss the limit cycles of the systemdx/dt=y·[1+(A(x)]oy/dt=(-x+δy+α_1x^2+α_2xy+α_5x^2y)[1+B(x)] (1)where A(x)=sum form i=1 to n(a_ix~), B(x)=sum form j=1 to m(β_jx^j) and 1+B(x)>0. We ... In this paper, we discuss the limit cycles of the systemdx/dt=y·[1+(A(x)]oy/dt=(-x+δy+α_1x^2+α_2xy+α_5x^2y)[1+B(x)] (1)where A(x)=sum form i=1 to n(a_ix~), B(x)=sum form j=1 to m(β_jx^j) and 1+B(x)>0. We prove that (1) possesses at most one limit cycle and give out the necessary and sufficient conditions of existence and uniqueness of limit cycles. 展开更多
关键词 necessary AND SUFFICIENT CONDITIONS OF EXISTENCE AND UNIQUENESS OF LIMIT CYCLES FOR A CLASS OF POLYNOMIAL SYSTEM LIM
在线阅读 下载PDF
SUFFICIENT AND NECESSARY CONDITIONS ON THE EXISTENCE AND ESTIMATES OF BOUNDARY BLOW-UP SOLUTIONS FOR SINGULAR p-LAPLACIAN EQUATIONS
4
作者 张学梅 阚士坤 《Acta Mathematica Scientia》 SCIE CSCD 2023年第3期1175-1194,共20页
Let?denote a smooth,bounded domain in R^(N)(N≥2).Suppose that g is a nondecreasing C^(1)positive function and assume that b(x)is continuous and nonnegative inΩ,and that it may be singular on■Ω.In this paper,we pro... Let?denote a smooth,bounded domain in R^(N)(N≥2).Suppose that g is a nondecreasing C^(1)positive function and assume that b(x)is continuous and nonnegative inΩ,and that it may be singular on■Ω.In this paper,we provide sufficient and necessary conditions on the existence of boundary blow-up solutions to the p-Laplacian problem△_(p)u=b(x)g(u)for x∈Ω,u(x)→+∞as dist(x,■Ω)→0.The estimates of such solutions are also investigated.Moreover,when b has strong singularity,the nonexistence of boundary blow-up(radial)solutions and infinitely many radial solutions are also considered. 展开更多
关键词 singular p-Laplacian equation boundary blow-up sub-supersolution method EXISTENCE nonexistence and estimates sufficient and necessary conditions
在线阅读 下载PDF
Some Necessary and Sufficient Condition of Multivariate Random Variable Satisfy Normal Distribution
5
作者 伍俊良 秦志仁 《Chinese Quarterly Journal of Mathematics》 CSCD 1996年第1期39-41,共3页
In this paper,we extended some results of article[1],obtain some sufficient and necessary condition which multivariate random variable satisfy normal distribution.
关键词 multivariate random variable normal distribution:sufficient and necessary condition
在线阅读 下载PDF
Is the High-Frequency Signal Necessary for the Resonance in the Delayed System?
6
作者 吕梅蕾 沈刚 +1 位作者 王海伦 杨建华 《Chinese Physics Letters》 SCIE CAS CSCD 2015年第1期15-17,共3页
In a delayed system excited by low-frequency and high-frequency signals, the necessity of the high-frequency signal on the resonance is discussed. By adjusting the delay time, the resonance occurs in a wide scope of f... In a delayed system excited by low-frequency and high-frequency signals, the necessity of the high-frequency signal on the resonance is discussed. By adjusting the delay time, the resonance occurs in a wide scope of frequencies, including the primary, subharmonic and superharmonic frequencies. Only for very few cases does the high-frequency signal have a positive effect on the resonance. It is the traditional vibrational resonance phenomenon. In most situations, the high-frequency excitation is unnecessary for the resonance. An appropriate delay, rather than the high-frequency signal, is the key factor in improving the weak low-frequency signal. 展开更多
关键词 Is the High-Frequency Signal necessary for the Resonance in the Delayed System
在线阅读 下载PDF
The Hyers-Ulam Stability and Hyers-Ulam Instability for Some Nonhomogeneous Ordinary Differential Equations
7
作者 DENG Jing-tao 《Chinese Quarterly Journal of Mathematics》 2024年第4期420-430,共11页
In this paper,we get a necessary and sufficient condition such that a class of differential inequalities hold.Using this necessary and sufficient condition,we prove that a class of first order nonhomogeneous ordinary ... In this paper,we get a necessary and sufficient condition such that a class of differential inequalities hold.Using this necessary and sufficient condition,we prove that a class of first order nonhomogeneous ordinary differential equations have the Hyers-Ulam stability.And then,we prove that some first order nonhomogeneous ordinary differential equations and some second order nonhomogeneous ordinary differential equations do not have the Hyers-Ulam instability under some suitable conditions. 展开更多
关键词 Hyers-Ulam stability Hyers-Ulam instability Ordinary differential equations necessary and sufficient condition
在线阅读 下载PDF
气象观测场在汽车试验场中的应用研究
8
作者 陈海建 《时代汽车》 2024年第14期172-174,178,共4页
汽车试验场作为汽车开展道路测试的重要场所,用于验证汽车产品的品质以及可靠性。除了场地道路外,气象条件作为汽车道路测试的重要一环,在《GB/T12534-1990汽车道路试验方法通则》中也有明确要求,如:试验时应是无雨无雾天气,相对湿度小... 汽车试验场作为汽车开展道路测试的重要场所,用于验证汽车产品的品质以及可靠性。除了场地道路外,气象条件作为汽车道路测试的重要一环,在《GB/T12534-1990汽车道路试验方法通则》中也有明确要求,如:试验时应是无雨无雾天气,相对湿度小于95%,气温0-40℃,风速不大于3m/s。同时气象条件也作为试验场道路管控的重要依据,实时风速、雨量、能见度等信息为场地管理者发布限速、限行、封场等通知提供必要参考依据,直接影响道路测试安全管控的及时性。因此,文章从气象观测场的建设、气象服务、异常天气道路管控等方面开展气象观测场在汽车试验场中的应用研究。 展开更多
关键词 汽车试验场 气象服务 道路管控 products. In addition to the SITE roads METEOROLOGICAL conditions are an important part of AUTOMOTIVE ROAD testing and there are also clear requirements in the GB/T12534-1990 General Rules for AUTOMOTIVE ROAD Test Methods. For example the test should be conducted in rain and fog free weather with a relative humidity of less than 95% a temperature of 0-40 and a wind SPEED of no more than 3m/s. At the same time METEOROLOGICAL conditions also serve as an important basis for ROAD control in the test site. Real time information such as wind SPEED rainfall and visibility provides necessary reference for SITE managers to issue notices on SPEED limits SITE closures and traffic restrictions directly affecting the timeliness of ROAD testing safety control. Therefore this article conducts research on the application of METEOROLOGICAL observation SITES in AUTOMOTIVE testing SITES from the construction of METEOROLOGICAL observation SITES METEOROLOGICAL services and abnormal weather ROAD control.
在线阅读 下载PDF
OPTIMALITY CONDITIONS AND DUALITY RESULTS FOR NONSMOOTH VECTOR OPTIMIZATION PROBLEMS WITH THE MULTIPLE INTERVAL-VALUED OBJECTIVE FUNCTION 被引量:4
9
作者 Tadeusz ANTCZAK 《Acta Mathematica Scientia》 SCIE CSCD 2017年第4期1133-1150,共18页
In this paper, both Fritz John and Karush-Kuhn-Tucker necessary optimality conditions are established for a (weakly) LU-efficient solution in the considered nonsmooth multiobjective programming problem with the mult... In this paper, both Fritz John and Karush-Kuhn-Tucker necessary optimality conditions are established for a (weakly) LU-efficient solution in the considered nonsmooth multiobjective programming problem with the multiple interval-objective function. Further, the sufficient optimality conditions for a (weakly) LU-efficient solution and several duality results in Mond-Weir sense are proved under assumptions that the functions constituting the considered nondifferentiable multiobjective programming problem with the multiple interval- objective function are convex. 展开更多
关键词 nonsmooth multiobjective programming problem with the multiple interval- objective function Fritz John necessary optimality conditions Karush-Kuhn- Tucker necessary optimality conditions (weakly) LU-efficient solution Mond- Weir duality
在线阅读 下载PDF
Reflective Practice on Effective Teaching Performance
10
作者 张宇超 《海外英语》 2014年第10X期145-146,共2页
Reflective practice is a vital parts of teaching process.The essay mainly states the theory of reflection,its functions,characteristics,and teachers' reflective practice.After obtaining data from the questionnaire... Reflective practice is a vital parts of teaching process.The essay mainly states the theory of reflection,its functions,characteristics,and teachers' reflective practice.After obtaining data from the questionnaire collected from 30 college English teachers' reflective practice,the writer analyzes the data and concludes that: reflection is a useful and necessary tool for successful teaching performance and the development of teachers. 展开更多
关键词 REFLECTION TEACHING PERFORMANCE necessary
在线阅读 下载PDF
SECOND-ORDER OPTIMALITY CONDITIONS FOR OPTIMAL CONTROL PROBLEMS GOVERNED BY 3-DIMENSIONAL NEVIER-STOKES EQUATIONS 被引量:5
11
作者 王丽娟 何培杰 《Acta Mathematica Scientia》 SCIE CSCD 2006年第4期729-734,共6页
This article is concerned with second-order necessary and sufficient optimality conditions for optimal control problems governed by 3-dimensional Navier-Stokes equations. The periodic state constraint is considered.
关键词 necessary and sufficient optimality conditions optimal control Navier-Stokes equation periodic state constraint
在线阅读 下载PDF
ON THE BOUNDEDNESS AND THE NORM OF A CLASS OF INTEGRAL OPERATORS 被引量:2
12
作者 周立芳 《Acta Mathematica Scientia》 SCIE CSCD 2015年第6期1475-1482,共8页
The boundedness and the norm of a class of integral operators Ta,b,c on Lλ^P spaces are studied in this paper. The author not only gives the sufficient and necessary condition for the boundedness of Ta,b,c on Lλ^P,b... The boundedness and the norm of a class of integral operators Ta,b,c on Lλ^P spaces are studied in this paper. The author not only gives the sufficient and necessary condition for the boundedness of Ta,b,c on Lλ^P,but also obtains its accurate norm on Lλ^P for some range under the condition of c = n + a + b. 展开更多
关键词 integral operators sufficient condition necessary condition operator norm hypergeometric functions
在线阅读 下载PDF
One new fractional-order chaos system and its circuit simulation by electronic workbench 被引量:1
13
作者 周平 程雪峰 张年英 《Chinese Physics B》 SCIE EI CAS CSCD 2008年第9期3252-3257,共6页
This paper proposes a new chaotic system and its fractional-order chaotic system. The necessary condition for the existence of chaotic attractors in this new fractional-order system is obtained. It finds that this new... This paper proposes a new chaotic system and its fractional-order chaotic system. The necessary condition for the existence of chaotic attractors in this new fractional-order system is obtained. It finds that this new fractional-order system is chaotic for q 〉 0.783 if the system parameter m=6. The chaotic attractors for q=0.8, and q=0.9 are obtained. A circuit is designed to realize its fractional-order chaos system for q=0.9 by electronic workbench. 展开更多
关键词 fractional-order chaotic systems necessary condition electronic workbench
在线阅读 下载PDF
Performance Analysis of Distributed Neyman-Pearson Detection Systems
14
作者 赵娟 陶然 +1 位作者 王越 周思永 《Journal of Beijing Institute of Technology》 EI CAS 2007年第3期305-309,共5页
The performance of a distributed Neyman-Pearson detection system is considered with the decision rules of the sensors given and the decisions from different sensors being mutually independent conditioned on both hypot... The performance of a distributed Neyman-Pearson detection system is considered with the decision rules of the sensors given and the decisions from different sensors being mutually independent conditioned on both hypothese. To achieve the better performance at the fusion center for a general detection system of n 〉 3 sensor configuration, the necessary and sufficient conditions are derived by comparing the probability of detec- tion at the fusion center with that of each of the sensors, with the constraint that the probability of false alarm at the fusion center is equal to that of the sensor. The conditions are related with the performances of the sensors and using the results we can predict the performance at the fusion center of a distributed detection system and can choose appropriate sensors to construct efficient distributed detection systems. 展开更多
关键词 decision fusion rule distributed detection Neyman-Pearson criterion probability of detection necessary and sufficient condition
在线阅读 下载PDF
On the Quasi-monotonic Problem
15
作者 ZHU Dong-mei WANG Zhi-guo 《Chinese Quarterly Journal of Mathematics》 CSCD 北大核心 2006年第3期461-464,共4页
This paper gives the necessary condition and one sufficient condition of the quasimonotonic function, and proves that the linear fractional function is quasi-monotone.
关键词 QUASI-MONOTONE necessary condition sufficient condition linear fractional function
在线阅读 下载PDF
Multi-agent consensus algorithm for second-order systems with a time-varying reference state
16
作者 宋莉 伍清河 《Journal of Beijing Institute of Technology》 EI CAS 2013年第3期387-393,共7页
Two second-order consensus algorithms with a time-vary reference state without relative velocity measurements are proposed in a directed topology. Necessary and sufficient conditions are presented to ensure second-ord... Two second-order consensus algorithms with a time-vary reference state without relative velocity measurements are proposed in a directed topology. Necessary and sufficient conditions are presented to ensure second-order consensus. It is shown that all the coupling strengths and the ei- genvalues of the Laplacian matrix play important roles in reaching consensus. Specially when all non- zero eigenvalues of the Laplacian matrix are real, consensus can be achieved if and only if the cou- pling strengths are positive and the directed topology has a spanning tree for the first algorithm, and for the second one, consensus can be achieved if and only if the coupling strengths are positive. Fi- nally, simulation examples are presented to verify the theoretical analysis. 展开更多
关键词 multi-agent system second-order consensus necessary and sufficient condition
在线阅读 下载PDF
Output neighboring-extremal and NCO tracking control in the optimal operation of CSTR
17
作者 许向阳 史晋峰 戴亚平 《Journal of Beijing Institute of Technology》 EI CAS 2013年第2期235-240,共6页
A new optimizing framework of process operation is proposed to deal with optimizing op- eration of continuous stirred tank reactor (CSTR). The optimization framework includes two layers: the first layer, necessary ... A new optimizing framework of process operation is proposed to deal with optimizing op- eration of continuous stirred tank reactor (CSTR). The optimization framework includes two layers: the first layer, necessary condition of optimally (NCO) tracking controller, calculates the optimal set-point of the process; and the second layer, output neighboring-extremal controller, calculates the input values of the controlled plant. The algorithm design and convergent analysis of output neighboring-extremal controller are discussed emphatically, and in the case of existing parametric uncertainty, the approach is shown to converge to the optimum atmost in two iterations. At last the approach is illustrated by simulation results for a dynamic CSTR. 展开更多
关键词 optimizing operation necessary condition of optimally NCO tracking output neigh-boring-extremal control continuous stirred tank reactor (CSTR)
在线阅读 下载PDF
The Absolute Stability of Several Classes of Nonlinear Control Systems
18
作者 张继业 邬平波 曾京 《Journal of Modern Transportation》 1999年第1期80-87,共8页
Absolute stability problem has theoretical and engineering importance for control engineering and control theory. In this paper, based on the dimension reducing method, sufficient conditions for the absolute stability... Absolute stability problem has theoretical and engineering importance for control engineering and control theory. In this paper, based on the dimension reducing method, sufficient conditions for the absolute stability of several classes of Lurie control systems are given. 展开更多
关键词 control system absolute stability necessary and sufficient conditions sufficient conditions
在线阅读 下载PDF
Pseudo Almost Periodic Solutions for Second Order Abstract Differential Equations
19
作者 谢灵红 顾晓慧 谢建华 《Journal of Southwest Jiaotong University(English Edition)》 2003年第1期98-102,共5页
On the assumption that the Cauchy problem for incomplete second order abstract differential equation (u″(t)=Au(t), -∞ <t <∞) is well posed and the Cauchy problem for complete second order abstract diff... On the assumption that the Cauchy problem for incomplete second order abstract differential equation (u″(t)=Au(t), -∞ <t <∞) is well posed and the Cauchy problem for complete second order abstract differential equation ( u″(t)+A 1u′(t)+A 0u(t)=0, t≥0 ) is strongly well posed, the necessary conditions for their solutions to be pseudo almost periodic are derived. 展开更多
关键词 pseudo almost periodic function second order abstract differential equation Cauchy problem necessary conditions
在线阅读 下载PDF
Network Decomposition and Maximum Independent Set Part Ⅰ:Theoretic Basis
20
作者 朱松年 朱嫱 《Journal of Southwest Jiaotong University(English Edition)》 2003年第2期103-121,共19页
The structure and characteristics of a connected network are analyzed, and a special kind of sub-network, which can optimize the iteration processes, is discovered. Then, the sufficient and necessary conditions for o... The structure and characteristics of a connected network are analyzed, and a special kind of sub-network, which can optimize the iteration processes, is discovered. Then, the sufficient and necessary conditions for obtaining the maximum independent set are deduced. It is found that the neighborhood of this sub-network possesses the similar characters, but both can never be allowed incorporated together. Particularly, it is identified that the network can be divided into two parts by a certain style, and then both of them can be transformed into a pair sets network, where the special sub-networks and their neighborhoods appear alternately distributed throughout the entire pair sets network. By use of this characteristic, the network decomposed enough without losing any solutions is obtained. All of these above will be able to make well ready for developing a much better algorithm with polynomial time bound for an odd network in the the application research part of this subject. 展开更多
关键词 odd network network transformation and decomposition negative envelope graph and pseudo-negative envelope graph the sufficient and necessary conditions polynomial time.
在线阅读 下载PDF
上一页 1 2 下一页 到第
使用帮助 返回顶部