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A mathematical model to achieve sustainable forest management

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International Journal of Modeling, Simulation, and Scientific Computing 2015年第4期6卷 112-129页

作者： A.K.Misra Kusum Lata department of mathematics Faculty of Science Banaras Hindu UniversityVaranasi 221005India

Forest resources are important natural resources for all living beings but they are continuously depleting due to overgrowth of human population and their development ***,conservation of forest resources is an important problem for sustainable *** view of this,in this paper,we have proposed and analyzed a nonlinear mathematical model to study the effects of economic and technological efforts on the conservation of forest *** the modeling process,it is assumed that due to increase in population size,the demand of population(population pressure)for forest products,lands,etc.,increases and to reduce this population pressure,economic efforts are employed proportional to the population ***,it is assumed that technological efforts in the form of genetically engineered plants are applied proportional to the depleted level of forest resources to conserve *** analysis reveals that increase in economic and technological efforts increases the density of forest resources but further increase in these efforts destabilizes the *** simulation is carried out to verify analytical findings and explore the effect of different parameters on the dynamics of model system.

关键词： Mathematical model forest resources economic efforts technological efforts.

Historical Arabic Images Classification and Retrieval Using Siamese Deep Learning Model

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computers, Materials & Continua 2022年第7期72卷 2109-2125页

作者： Manal M.Khayyat Lamiaa A.Elrefaei Mashael M.Khayyat computer science department Umm Al-Qura UniversityMakkahSaudi Arabia computer science department King Abdulaziz UniversityJeddahSaudi Arabia Electrical Engineering department Faculty of Engineering at ShoubraBenha UniversityCairoEgypt department of Information Systems and Technology College of Computer Science and EngineeringUniversity of JeddahJeddahSaudi Arabia

Classifying the visual features in images to retrieve a specific image is a significant problem within the computer vision field especially when dealing with historical faded colored ***,there were lots of efforts trying to automate the classification operation and retrieve similar images *** reach this goal,we developed a VGG19 deep convolutional neural network to extract the visual features from the images ***,the distances among the extracted features vectors are measured and a similarity score is generated using a Siamese deep neural *** Siamese model built and trained at first from scratch but,it didn’t generated high evaluation ***,we re-built it from VGG19 pre-trained deep learning model to generate higher evaluation ***,three different distance metrics combined with the Sigmoid activation function are experimented looking for the most accurate method formeasuring the similarities among the retrieved *** that the highest evaluation parameters generated using the Cosine distance ***,the Graphics Processing Unit(GPU)utilized to run the code instead of running it on the Central Processing Unit(CPU).This step optimized the execution further since it expedited both the training and the retrieval time *** extensive experimentation,we reached satisfactory solution recording 0.98 and 0.99 F-score for the classification and for the retrieval,respectively.

关键词： Visual features vectors deep learning models distance methods similar image retrieval

Blow-up behavior of Hammerstein-type delay Volterra integral equations

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Frontiers of mathematics in China 2013年第2期8卷 261-280页

作者： Zhanwen YANG Hermann BRUNNER science Research Center Academy of Fundamental and Interdisciplinary Science department of mathematics Harbin Institute of Technology Harbin 150001 China department of mathematics Hong Kong Baptist University Hong Kong SAR China department of mathematics and Statistics Memorial University of NewfoundlandSt. John's NL AIC 557 Canada

We consider the blow-up behavior of Hammerstein-type delay Volterra integral equations （DVIEs）. Two types of delays, i.e., vanishing delay （pantograph delay） and non-vanishing delay （constant delay）, are considered. With the same assumptions of Volterra integral equations （VIEs）, in a similar technology to VIEs, the blow-up conditions of the two types of DVIEs are given. The blow-up behaviors of DVIEs with non-vanishing delay vary with different initial functions and the length of the lag, while DVIEs with pantograph delay own the same blow-up behavior of VIEs. Some examples and applications to delay differential equations illustrate this influence.

关键词： Delay Volterra integral equation (DVIE) non-vanishing delay vanishing delay blow-up of solution

APPROXIMATING SOLUTION OF 0 ∈T(x) FOR AN H-MONOTONE OPERATOR IN HILBERT SPACES

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Acta Mathematica Scientia 2013年第5期33卷 1347-1360页

作者：刘三阳贺慧敏陈汝栋 department of mathematics Xidian University department of mathematics Tianjin Polytechnic University

The purpose of this paper is to study the solution of 0∈ T（x） for an H- monotone operator introduced in [Fang and Huang, Appl. Math. Comput. 145（2003）795- 803] in Hilbert spaces, which is the first proposal of it＇s kind. Some strong and weak convergence results are presented and the relations between maximal monotone operators and H-monotone operators are analyzed. Simultaneously, we apply these results to the minimization problem for T = δf and provide some numerical examples to support the theoretical findings.

关键词： H-monotone operators inclusion problem 0 ∈ T(x) resolvent operator strong convergence weak convergence

Existence of best simultaneous approximations in L_p(S, Σ, X) without the RNP assumption

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science China mathematics 2015年第4期58卷 813-820页

作者： LUO XianFa LI Chong department of mathematics China Jiliang University department of mathematics Zhejiang University

Let(S, Σ, μ) be a complete positive σ-finite measure space and let X be a Banach space. We consider the simultaneous proximinality problem in Lp(S, Σ, X) for 1 p < +∞. We establish some N-simultaneous proximinality results of Lp(S, Σ0, Y) in Lp(S, Σ, X) without the Radon-Nikody′m property(RNP) assumptions on the space span Y and its dual span Y*, where Σ0is a sub-σ-algebra of Σ and Y a nonempty locally weakly compact closed convex subset of X. In particular, we completely solve one open problem and partially solve another one in Luo et al.(2011).

关键词： measure space the Radon-Nikodym property simultaneous approximation

Additive Lie (ξ-Lie) Derivations and Generalized Lie (ξ-Lie) Derivations on Prime Algebras

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Acta Mathematica Sinica,English Series 2013年第2期29卷 383-392页

作者： Xiao Fei QI Jin Chuan HOU department of mathematics Shanxi University department of mathematics Taiyuan University of Technology

The additive （generalized） ξ-Lie derivations on prime algebras are characterized. It is shown, under some suitable assumptions, that an additive map L is an additive generalized Lie derivation if and only if it is the sum of an additive generalized derivation and an additive map from the algebra into its center vanishing all commutators; is an additive （generalized） E-Lie derivation with ξ -if and only if it is an additive （generalized） derivation satisfying L（ξA） =- ξL（A） for all A. These results are then used to characterize additive （generalized） ξ-Lie derivations on several operator Mgebras such as Banach space standard operator algebras and yon Neumman algebras.

关键词： Prime algebras ξ-Lie derivations generalized ξ-Lie derivations

Global analysis of smooth solutions to a hyperbolic-parabolic coupled system

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Frontiers of mathematics in China 2013年第6期8卷 1437-1460页

作者： Yinghui ZHANG Haiying DENG Mingbao SUN department of mathematics Hunan Institute of Science and Technology Yueyang 414006 China School of mathematics and Statistics Central China Normal University Wuhan 430079 China department of mathematics Hunan First Normal College Changsha 410205 China

We investigate a model arising from biology, which is a hyperbolic- parabolic coupled system. First, we prove the global existence and asymptotic behavior of smooth solutions to the Cauchy problem without any smallness assumption on the initial data. Second, if the Hs ∩ Ll-norm of initial data is sufficiently small, we also establish decay rates of the global smooth solutions. In particular, the optimal L2 decay rate of the solution and the almost optimal L2 decay rate of the first-order derivatives of the solution are obtained. These results are obtained by constructing a new nonnegative convex entropy and combining spectral analysis with energy methods.

关键词： Global analysis hyperbolic-parabolic system decay rate convex entropy

THE ESTIMATE OF THE RANK FOR REGRESSION COEFFICIENT MATRIX IN A MEDIAN REGRESSION MODEL

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Chinese Annals of mathematics,Series B 1992年第2期13卷 205-214页

作者：缪柏其 department of mathematics University of Science and Technology of China Hefei Anhui 230026 China

It is discussed to infer the rank of regression coefficient matrix in a multivariate linear regression model. If the zero median vector is unique and the design matrices satisfy some weaker conditions, it is derived that the estimators of the rank of regression coefficient matrix under the minimum distance criterion by using model selection method is strongly consistent.

关键词： multivariate median satisfy criterion matrices infer hereafter Borel lemma underlying

Existence results for generalized vector equilibrium problems with applications

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Applied mathematics and Mechanics(English Edition) 2014年第7期35卷 913-924页

作者：杨明歌黄南京 department of mathematics Luoyang Normal University department of mathematics Sichuan University

By a coincidence theorem, some existence theorems of solutions are proved for four types of generalized vector equilibrium problems with moving cones. Applications to the generalized semi-infinite programs with the generalized vector equilibrium constraints under the mild conditions are also given. The results of this paper unify and improve the corresponding results in the previous literature.

关键词： generalized vector equilibrium problem generalized semi-infinite program,abstract convex space -map