检索结果-南通市图书馆

A reconstructed discontinuous Galerkin method for compressible flows on moving curved grids

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Advances in Aerodynamics 2021年第1期3卷 1-28页

作者： Chuanjin wang and Hong luo Department of Mechanical and Aerospace Engineering North Carolina State UniversityRaleigh 27695NCUSA

A high-order accurate reconstructed discontinuous Galerkin(rDG)method is developed for compressible inviscid and viscous flows in arbitrary Lagrangian-Eulerian(ALE)formulation on moving and deforming unstructured curved *** basis functions in the rDG method are defined on the time-dependent domain,where the integration and computations are *** Geometric Conservation Law(GCL)is satisfied by modifying the grid velocity terms on the right-hand side of the discretized equations at Gauss quadrature points.A radial basis function(RBF)interpolation method is used for propagating the mesh motion of the boundary nodes to the interior of the mesh.A third order Explicit first stage,Single Diagonal coefficient,diagonally Implicit Runge-Kutta scheme(ESDIRK3)is employed for the temporal integration.A number of benchmark test cases are conducted to assess the accuracy and robustness of the rDG-ALE method for moving and deforming boundary *** numerical experiments indicate that the developed rDG method can attain the designed spatial and temporal orders of accuracy,and the RBF method is effective and robust to avoid excessive distortion and invalid elements near moving boundaries.

关键词： Arbitrary Lagrangian-Eulerian Reconstructed discontinuous Galerkin High-order ESDIRK3 Radial basis function Navier-Stokes

Per-unit Scheme for Integrated Solution of Hybrid Power-water Flow Problem

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Modern Power Systems and Clean Energy 2023年第2期11卷 680-685页

作者： Xia Zhao Hong Tan luo wang Mingyi Sun State Key Laboratory of Power Transmission Equipment&System Security and New Technology Chongqing UniversityChongqingChina

When applying the widely-used Newton-Raphson(N-R)method to the integrated solution of the hybrid power-water flow problem of the power-water integrated energy system(PW-IES),it is found that there are numerical differences among Jacobian elements,which may yield an ill-conditioned Jacobian matrix and even cause convergence ***,this letter proposes to per-unitize the water distribution network(WDN)to reduce the numerical differences and thus to improve the Jacobian matrix conditioning and the integrated N-R solution to the hybrid power-water flow problem.

关键词： Integrated energy system load flow Newton-Raphson method water distribution network power-water flow

In situ synthesis of magnetic mesoporous silica via sol-gel process coupled with precipitation and oxidation

在线全文

学校读者我要写书评

暂无评论

Particuology 2011年第1期9卷 56-62页

作者： Junqi Zhao Yujun wang Guangsheng luo Shenlin Zhu The State Key Laboratory of Chemical Engineering Department of Chemical Engineering Tsinghua University Beijing 100084 China

A novel method was proposed for the in situ synthesis of magnetite-containing mesoporous silica SBA- 16 via a sol-gel process coupled with precipitation and oxidation. The effect of the added amounts of reactants on the mesostructural and magnetic properties of the magnetic mesoporous silica was inves- tigated, It was determined that the synthesized magnetic mesoporous silica with a total pore volume of 0.64-0.96 cm3/g and an average pore diameter of 4.0-14,9 nm had a relatively high saturation mag- netization value （1.11-5.77 emu/g） and a large surface area （258-747 m2/g）, Lysozyme was chosen as a model protein to test the performance of the magnetic mesoporous silica as a protein adsorbent, The high adsorption capacity （up to 212 mg/g） suggested a promising future as bimolecular hosts for the magnetic mesoporous silica.

关键词： Magnetic mesoporous silica Mesostructural property Magnetic property Protein absorbent

Preparation and functionalization of mesoporous silica spheres as packing materials for HPLC

在线全文

学校读者我要写书评

暂无评论

Particuology 2008年第3期6卷 143-148页

作者： Liming Yang Yujun wang Guangsheng luo Youyuan Dai The State Key Laboratory of Chemical Engineering Department of Chemical Engineering Tsinghua University Beijing 100084 China

This paper presents the integrated results of a series of new methods for preparing mesoporous silica spheres as high-performance liquid chromatography （HPLC） packing materials. The separation performance of the mesoporous spheres materials has also been determined. Micrometer- sized silica spheres with uniform spherical morphologies and ordered mesostructures were first successfully synthesized by the method employing a water-soluble polymer-assisted assembly. Then the templates for getting ordered mesoporous materials with high-density silanol groups were removed by using hydrothermal oxidation. Finally the silica spheres were functionalized with C8 alkyl groups by surface modification under hydrothermal conditions. The resultant functionalized silica spheres were demonstrated to be excellent oacking materials for HPLC.

关键词： Mesoporous Silica sphere Water-soluble polymer Assembly HPLC

Novel infrared and visible image fusion method based on independent component analysis

在线全文

学校读者我要写书评

暂无评论

Frontiers of Computer Science 2014年第2期8卷 243-254页

作者： Yin LU Fuxiang wang Xiaoyan luo Feng LIU National Key Laboratory of CNS/ATM School of Electronics and Information Engineering Beihang University Beijing 100191 China

The goal of infrared （IR） and visible image fu- sion is for the fused image to contain IR object features from the IR image and retain the visual details provided by the visible image. The disadvantage of traditional fusion method based on independent component analysis （ICA） is that the primary feature information that describes the IR objects and the secondary feature information in the IR image are fused into the fused image. Secondary feature information can de- press the visual effect of the fused image. A novel ICA-based IR and visible image fusion scheme is proposed in this paper. ICA is employed to extract features from the infrared image, and then the primary and secondary features are distinguished by the kurtosis information of the ICA base coefficients. The secondary features of the IR image are discarded during fu- sion. The fused image is obtained by fusing primary features into the visible image. Experimental results show that the pro- posed method can provide better perception effect.

关键词： image fusion independent component analysis(ICA) feature extraction kurtosis

Cooling Curve of Strange Star in Strong Magnetic Field

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Communications in Theoretical Physics 2008年第11期50卷 1255-1257页

作者： wang Xiao-Qin luo Zhi-Quan Institute of Physics and Electronic Information China West Normal University Nanchong 637002 China

In this paper, firstly, we investigate the neutrino emissivity from quark Urca process in strong magnetic field. Then, we discuss the heat capacity of strange stars in strong magnetic field. Finally, we give the cooling curve in strong magnetic field. In order to make a comparison, we also give the corresponding cooling curve in the case of null magnetic field. It turns out that strange stars cool faster in strong magnetic field than that without magnetic field.

关键词： strong magnetic field strange star quark

Cloning of the key genes in maize oxylipins pathways and their roles in herbivore induced defense

在线全文

学校读者我要写书评

暂无评论

Chinese Science Bulletin 2005年第21期50卷 2457-2466页

作者： XU Tao wang Jianwu luo Shiming Institute of Tropical and Subtropical Ecology South China Agricultural University Guangzhou 510642 China

To gain an understanding of the molecular ba-sis of signaling pathways in herbivore-induced maize plant defense, three key genes, ZmAOS, ZmAOC and ZmHPL, which are involved in the biosynthesis of oxylipin signals, have been cloned using RT-PCR in this study. Beet army-worm (BAW) infestation induced the systemic expression of the key genes involved in the biosynthesis of oxylipin signals similar to exogenous methyl jasmonate (MeJA). Moreover, the systemic expression patterns of maize defense-related genes were similar between maize leaves induced by jas-monic acid (JA) and damaged by BAW. Previous treatment with salicyhydroxamic acid (SHAM), an inhibitor of jas-monates (JAs) signal pathway followed by BAW infestation did not induce the systemic expression of the defense-related genes. Exposure to the vapors of green leafy volatiles (GLVs, (Z)-3-hexen-1-ol, (E)-2-hexenal, (E)-3-hexenal) and β-oci- mene induced the expression of the defense-related genes, as well as the key genes involved in biosynthesis of JAs. How-ever, previous treatment with SHAM clearly decreased the transcript levels of the defense genes induced by (Z)-3-hexen-1-ol, (E)-2-hexenal and (E)-3- hexenal. These results demonstrate the major role of oxylipin signal path-way in herbivore-induced maize chemical defense. JA was the endogenous signal in the process of herbivore-induced maize systemic defense. GLVs, another group of oxylipin, played an important role in the process of herbivore-induced systemic defense outside the plant. Furthermore, the expres-sion of defense-related genes induced by GLVs was partially dependent on JAs signal pathway, while β-ocimene induction was independent of JAs signal pathway.

关键词：玉米繁殖技术基因表达茉莉酮

Distributed Graph Database Load Balancing Method Based on Deep Reinforcement Learning

在线全文

学校读者我要写书评

暂无评论

Computers, Materials & Continua 2024年第6期79卷 5105-5124页

作者： Shuming Sha Naiwang Guo wang luo Yong Zhang Nanjing NARI Information&Communication Technology Co. Ltd.Nanjing210032China State Grid Electric Power Research Institute Nanjing211106China State Grid Shanghai Municipal Eleciric Power Company Shanghai200122China

This paper focuses on the scheduling problem of workflow tasks that exhibit *** indepen-dent batch tasks,workflows typically consist of multiple subtasks with intrinsic correlations and *** necessitates the distribution of various computational tasks to appropriate computing node resources in accor-dance with task dependencies to ensure the smooth completion of the entire *** scheduling must consider an array of factors,including task dependencies,availability of computational resources,and the schedulability of ***,this paper delves into the distributed graph database workflow task scheduling problem and proposes a workflow scheduling methodology based on deep reinforcement learning(DRL).The method optimizes the maximum completion time(makespan)and response time of workflow tasks,aiming to enhance the responsiveness of workflow tasks while ensuring the minimization of the *** experimental results indicate that the Q-learning Deep Reinforcement Learning(Q-DRL)algorithm markedly diminishes the makespan and refines the average response time within distributed graph database *** quantifying makespan,Q-DRL achieves mean reductions of 12.4%and 11.9%over established First-fit and Random scheduling strategies,***,Q-DRL surpasses the performance of both DRL-Cloud and Improved Deep Q-learning Network(IDQN)algorithms,with improvements standing at 4.4%and 2.6%,*** reference to average response time,the Q-DRL approach exhibits a significantly enhanced performance in the scheduling of workflow tasks,decreasing the average by 2.27%and 4.71%when compared to IDQN and DRL-Cloud,*** Q-DRL algorithm also demonstrates a notable increase in the efficiency of system resource utilization,reducing the average idle rate by 5.02%and 9.30%in comparison to IDQN and DRL-Cloud,*** findings support the assertion that Q-DRL not only upholds a lower average

关键词： Reinforcement learning workflow task scheduling load balancing

Rotation speed measurement of moving particles in a CFB riser

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Particuology 2009年第4期7卷 238-244页

作者： Xuecheng Wu Qinhui wang Zhongyang luo Mengxiang Fang Kefa Cen State Key Laboratory of Clean Energy Utilization Zhejiang University Hangzhou Zhejiang 310027 China

This paper presents a study on measuring rotation speed of moving glass beads with an average diameter of 500 p.m in a pilot-scale circulating fluidized bed （CFB） riser with a high-speed digital imaging system. Two methods have been developed to calculate particle rotation speed from the particle images. The first method consists of a fully automated algorithm based on cross-correlation of gray distribution of particle images for particles whose rotation axes are （nearly） perpendicular to the imaging plane, and the second method calculates the speed of particle rotation by identifying its rotation axis using two or more characteristic points on its surface. The reliability of the two methods is verified by using a small sphere with known speed and direction of rotation. The first method is shown to be capable of measuring accurately the rotation speed for the particle with a rotation axis （nearly） perpendicular to the imaging plane and filtering off other particles using an appropriate threshold of correlation coefficient. The second method is shown to be capable of yielding both the speed and direction of particle rotation, with a measurement error of less than 10%. Results of both methods on real glass beads in a CFB riser are compared against each other.

关键词： Rotation speed measurement Moving particles Gas-solid flow Circulating fluidized bed (CFB)