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Acta Mathematica Scientia 2024年第2期44卷 702-720页

作者： N.HOSEINPOOR M.GHAZNAVI faculty of mathematical sciences Shahrood University of TechnologyShahroodIran

In this article, a novel scalarization technique, called the improved objective-constraint approach, is introduced to find efficient solutions of a given multiobjective programming problem. The presented scalarized problem extends the objective-constraint problem. It is demonstrated that how adding variables to the scalarized problem, can lead to find conditions for (weakly, properly) Pareto optimal solutions. Applying the obtained necessary and sufficient conditions, two algorithms for generating the Pareto front approximation of bi-objective and three-objective programming problems are designed. These algorithms are easy to implement and can achieve an even approximation of (weakly, properly) Pareto optimal solutions. These algorithms can be generalized for optimization problems with more than three criterion functions, too. The effectiveness and capability of the algorithms are demonstrated in test problems.

关键词： multiobjective optimization Pareto front scalarization objective-constraint approach proper efficient solution

Proteostasis failure:at the intersection between aging and Alzheimer's disease

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Neural Regeneration Research 2025年第11期20卷 3221-3222页

作者： Natalia Poblete Claudio Hetz Center for Geroscience Brain Health and MetabolismSantiagoChile Biomedical Neuroscience Institute Faculty of MedicineUniversity of ChileSantiagoChile Program of Cellular and Molecular Biology Institute of Biomedical SciencesFaculty of MedicineUniversity of ChileSantiagoChile Buck Institute for Research on Aging NovatoCAUSA

Lifestyle and demographics of the world's population are causing serious health problems impacting the brain,increasing the incidence of Alzheimer's disease(AD)and other types of *** we have gained important insights into the pathogenic mechanisms of AD,only palliative care is available to *** is characterized by the abnormal deposition of protein aggregates in the brain formed by amyloid β and hyper-phosphorylated,Tau in addition to neuroinflammation.

关键词： Alzheimer amyloid stasis

Rare Earth Elements Geochemistry of Sheikh-Marut Laterite Deposit,NW Mahabad,West-Azarbaidjan Province,Iran

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Acta Geologica Sinica(English Edition) 2013年第1期87卷 176-185页

作者： Ali ABEDINI Ali Asghar CALAGARI Geology Department Faculty of SciencesUrmia University Geology Department Faculty of Natural SciencesUniversity of Tabriz

Laterite deposit at Sheikh-Marut （NW occurred within middle-upper Permian carbonate Mahabad, West-Azarbaidjan province, Iran） rocks. It consists of seven stratiform and/or discontinuous lenticular layers extending over 4.2 km in length and having thicknesses ranging from 3 to 14 m. Mineralogical data show that the ores contain kaolinite and hematite as major and boehmite, diaspore, halloysite, amesite, anatase, and muscovite-illite as minor mineral phases. The computed Ce anomaly values in the ores range from 0.05 to 20.84. Conservative index （e.g., Eu/Eu＊） suggests that this deposit is a product of alteration and weathering of basaltic rocks. Rhythmic increment of EREE values of the ores with approaching to the carbonate bedrocks shows an in-situ occurrence of lateritization processes. Mass change calculations of elements indicate that two competing processes namely leaching and fixation were the major regulating factors in concentration variation of REEs （La-Lu） in this deposit. The obtained results show that pH increase of weathering solutions by carbonate bedrocks, existence of organic matters, and the degree of comlexation with organic ligands played remarkable role in distribution of REEs during lateritization. Further geochemical considerations revealed that secondary phosphates, Mn-oxides and -hydroxides, diaspore, and anatase were the potential hosts for REEs in this deposit.

关键词： laterite geochemistry REEs Sheikh-Marut deposit Mahabad Iran

Boundary layer flow over a moving surface in a nanofluid with suction or injection

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Acta Mechanica Sinica 2012年第1期28卷 34-40页

作者： Norfifah Bachok Anuar Ishak Ioan Pop Department of Mathematics and Institute for mathematical Research Faculty of Science Universiti Putra Malaysia School of mathematical sciences Faculty of Science and Technology Universiti Kebangsaan Malaysia faculty of Mathematics University of Cluj

An analysis is performed to study the heat transfer characteristics of steady two-dimensional boundary layer flow past a moving permeable flat plate in a nanofluid. The effects of uniform suction and injection on the flow field and heat transfer characteristics are numerically studied by using an implicit finite difference method. It is found that dual solutions exist when the plate and the free stream move in the opposite directions. The results indicate that suction delays the boundary layer separation, while injection accelerates it.

关键词： Nanofluid .Moving plate. Boundary layer. Suction/injection - Dual solutions

Stochastic H_2/H_∞ Control with Random Coefcients

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Chinese Annals of Mathematics,Series B 2013年第5期34卷 733-752页

作者： Meijiao WANG Department of mathematical Finance and Stochastic Control School of Mathematical SciencesFudanUniversity faculty of Science Ningbo University

Abstract This paper is concerned with the mixed H2/H∞ control for stochastic systems with random coefficients, which is actually a control combining the H2 optimization with the H∞ robust performance as the name of H2/H∞ reveals. Based on the classical theory of linear-quadratic （LQ, for short） optimal control, the sufficient and necessary conditions for the existence and uniqueness of the solution to the indefinite backward stochastic Riccati equation （BSRE, for short） associated with H∞ robustness are derived. Then the sufficient and necessary conditions for the existence of the H2/H∞ control are given utilizing a pair of coupled stochastic Pdccati equations.

关键词： Stochastic H∞ control Stochastic H2/H∞ control Linear quadratic(LQ) optimal control Indefinite backward stochastic Riccati equation

Evaluation of entomopathogenic Bacillus sphaericus isolated from Lombok beach area against mosquito larvae

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Asian Pacific Journal of Tropical Biomedicine 2016年第2期6卷 148-154页

作者： Bambang Fajar Suryadi Bagyo Yanuwiadi Tri Ardyati Suharjono Suharjono Department of Biology Faculty of Mathematics Natural Sciences Mataram University Department of Biology Faculty of Mathematics Natural Sciences Brawijaya University

Objective: To isolate, characterize and evaluate toxicity of Bacillus sphaericus(B. sphaericus) from beach area of Lombok ***: Soil was collected from determined locations and suspended in sterile physiological saline water. After heat shock was applied, suspension was spread on NYSM agar medium. Colonies grown were then observed and isolated. Colony, cell morphology,and biochemical/physiological characteristics were tested and compared to B. sphaericus2362 as standard. Initial toxicity testing was done against three species of mosquito larvae(Culex quinquefasciatus, Anopheles aconitus and Aedes aegypti) and isolates that showed more than 50% larvae killing will be assayed to obtain LC_(50) and LC_(90)values within 48 *** technique were conducted to obtain 16 s r DNA amplicon for sequencing and to detect toxin-expressing genes(using multiplex PCR).Results: Twenty isolates of B. sphaericus have been collected from 20 determined locations and their characteristics were in agreement with standard B. sphaericus characteristics. Bioassay testing showed that four isolates(namely isolate MNT, SLG, TJL2 and PLG) were mildly toxic against all larvae. The rests were either low toxic or non-toxic at *** analysis showed that all four isolates were clustered with other known mildly and highly toxic strains. The multiplex PCR result showed four toxic isolates owned 1–2bands from Bin toxin genes and three bands from Mtx toxin genes, whereas 16 isolates with low to non-toxic characteristics showed only three bands from Mtx toxin ***: Four toxic isolates of B. sphaericus were isolated from beach area of Lombok Island. They showed mild toxicity against larvae of three mosquito species.

关键词： Bacillus sphaericus Lombok Island Mosquito larvae Culex quinquefasciatus Anopheles aconitus Aedes aegypti

LIMITED TOMOGRAPHY RECONSTRUCTION VIA TIGHT FRAME AND SIMULTANEOUS SINOGRAM EXTRAPOLATION

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Journal of Computational Mathematics 2016年第6期34卷 575-589页

作者： Jae Kyu Choi Bin Dong Xiaoqun Zhang Institute of natural sciences Shanghai Jiao Tong University Shanghai China Beijing International Center for mathematical Research Peking University Beijing China Institute of natural sciences School of Mathematical Sciences and MOE-LSC Shanghai Jiao Tong University Shanghai China

X-ray computed tomography （CT） is one of widely used diagnostic tools for medical and dental tomographic imaging of the human body. However, the standard filtered back- projection reconstruction method requires the complete knowledge of the projection data. In the case of limited data, the inverse problem of CT becomes more ill-posed, which makes the reconstructed image deteriorated by the artifacts. In this paper, we consider two dimensional CT reconstruction using the projections truncated along the spatial direc- tion in the Radon domain. Over the decades, the numerous results including the sparsity model based approach has enabled the reconstruction of the image inside the region of interest （ROI） from the limited knowledge of the data. However, unlike these existing methods, we try to reconstruct the entire CT image from the limited knowledge of the sinogram via the tight frame regularization and the simultaneous sinogram extrapolation. Our proposed model shows more promising numerical simulation results compared with the existing sparsity model based approach.

关键词： X-ray computed tomography Limited tomography Wavelet frame Data driventight frame Bregmanized operator splitting algorithm Sinogram extrapolation.

ON EXISTENCE OF SOLUTIONS OF DIFFERENCE RICCATI EQUATION

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Acta Mathematica Scientia 2019年第1期39卷 139-147页

作者： Zongxuan CHEN Kwang Ho SHON School of mathematical sciences South China Normal University Department of Mathematics College of Natural Sciences Pusan National University

Consider the difference Riccati equation f(z+1) =(A(z)f(z)+B(z))/(C(z)f(z)+D(z)),where A,B, C,D are meromorphic functions, we give its solution family with one-parameter H(f(z))={f_0(z),f(z)=((f_1(z)-f_0(z))(f_2(z)-f_0(z)))/(Q(z)(f_2(z)-f_1(z))+(f_2(z)-f_0(z)))}, where Q(z) is any constant in C or any periodic meromorphic function with period 1, and f_0(z),f_1(z),f_2(z) are its three distinct meromorphic solutions.

关键词： difference Riccati equation solution family order of growth

On the mean field limit of the Random Batch Method for interacting particle systems

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Science China Mathematics 2022年第1期65卷 169-202页

作者： Shi Jin Lei Li School of mathematical sciences Institute of Natural SciencesMOE-LSCShanghai Jiao Tong UniversityShanghai 200240China

The Random Batch Method proposed in our previous work(Jin et al.J Comput Phys,2020)is not only a numerical method for interacting particle systems and its mean-field limit,but also can be viewed as a model of the particle system in which particles interact,at discrete time,with randomly selected mini-batch of *** this paper,we investigate the mean-field limit of this model as the number of particles N→∞.Unlike the classical mean field limit for interacting particle systems where the law of large numbers plays the role and the chaos is propagated to later times,the mean field limit now does not rely on the law of large numbers and the chaos is imposed at every discrete *** this,we will not only justify this mean-field limit(discrete in time)but will also show that the limit,as the discrete time intervalτ→0,approaches to the solution of a nonlinear Fokker-Planck equation arising as the mean-field limit of the original interacting particle system in the Wasserstein distance.

关键词： Random Batch Method mean field limit chaos Wasserstein distance nonlinear Fokker-Planck equation

SUBNORMAL SOLUTIONS OF DIFFERENTIAL EQUATIONS WITH PERIODIC COEFFICIENTS

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Acta Mathematica Scientia 2010年第1期30卷 75-88页

作者：陈宗煊孙光镐 School of mathematical sciences South China Normal University Department of Mathematics College of Natural SciencesPusan National University

In this article, we apply the concept of hyper-order to higher order linear differential equations with periodic coefficients, investigate the existence and the form of its subnormal solution, and estimate the growth of all other solutions, and answer the question raised by Gundersen and Steinbart for more general periodic differential equations.

关键词： periodic equation subnormal solution hyper order