检索结果-南通市图书馆

Effect of cylinder wall parameters on the final packing density of mono-disperse spheres subject to three-dimensional vibrations Author links open overlay panel

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 2024年第8期91卷 211-225页

作者： Jack r.Grogan Andrei L.Nicuşan chris.opher r.k.windows.yule School of Chemical Engineering The University of BirminghamEdgbastonBirminghamB152TTUK

Achieving densely packed particles is desirable within the industries of ceramics,pharmaceuticals,defence and additive *** this work,we use the discrete element method(DEM)to determine the effect of wall parameters on the final packing density of mono-disperse spheres subject to 4 varying three-dimensional vibration and fill *** focus specifically on the impact of the container wall parameters on the particles'final packing *** on from the validation of the DEM simulation the particle-wall coefficient of restitution,the particle-wall coefficient of rolling friction and the particle-wall coefficient of sliding friction were varied individually and the effect on the final packing density *** relatively low particle-particle friction glass beads,the effect of these wall properties had no discernible effect on the final packing density *** on from these findings the particle-wall properties were varied at the extreme values of particle-particle coefficient of rolling friction and particle-particle coefficient of sliding *** a particle-particle coefficient of sliding friction=1,increases in particle-wall coefficient of restitution resulted in a minor increase in the final packing density of particles though this was not statistically *** a particle-particle coefficient of sliding friction=1,increases in particle-wall coefficient of rolling friction resulted in a minor decrease in the final packing density of the particles though again not to a degree where the trend can,with complete certainty,be distinguished from the random error across the ***,when the particle-particle coefficient of sliding friction=1,increases in particle-wall coefficient of sliding friction resulted in a significant decrease in the final packing density of *** decrease was attributed to the propagation of force chains throughout the *** significant decrease in final packing density with

关键词： Vibropacking Packing Densification Vibration Discrete element method Friction Wall friction restitution

Positron Emission Projection Imaging:A technique for concentration field measurements in opaque industrial systems

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 2024年第11期94卷 1-15页

作者： roberto Hart-Villamil Jack Sykes Andy Ingram chris.opher r.k.windows.yule Santosh kumar Gupta School of Chemical Engineering University of BirminghamB152TTUK School of Physics and Astronomy University of BirminghamB152TTUK Hindustan Unilever r&D BengaluruKarnataka560066India

A novel Positron Emission Projection Imaging(PEPI)algorithm designed to compute the plane-projected spatial distribution of radiolabelled materials without the need for collimation is *** leveraging improved data efficiency,we have achieved a technique with enhanced spatial resolution and temporal resolution compared to previous PEPI *** of this algorithm was conducted using synthetic data generated from a digital twin of a PET scanner,demonstrating its accuracy for practical *** industrial advantage of this novel algorithm was applied in the imaging of laminar flow mixing within a ploughshare mixer,with the experimental results compared against those obtained from validated computational fluid dynamics(CFD)*** comparison highlights an important use case for PEPI as a robust validation tool for CFD simulations,crucial for enhancing industrial ***,which uses deeply penetrating gamma-photons,is now capable of imaging opaque fluids and solids in industrial *** directions for this work include further algorithmic refinements and expanding its application across various industrial systems,establishing PEPI as a robust tool for in-depth industrial process *** advancements presented here allow for optimized mixer design and enhanced process efficiency,extending the frontiers of tomographic imaging in industrial applications.

关键词： Positron emission projection imaging Positron emission particle tracking Computational fluid dynamics Mixing Ploughshare mixer

Evaluation of coarse-grained CFD-DEM models with the validation of PEPT measurements

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 2023年第11期82卷 48-63页

作者： Hanqiao Che Dominik Werner Jonathan Seville Tzany kokalova Wheldon kit windows-yule School of Chemical Engineering University of BirminghamB152TTUK School of Physics and Astronomy University of BirminghamBirminghamB152TTUK

Computational Fluid Dynamics coupled with Discrete Element Method (CFD-DEM) is a commonly used numerical method to model gas-solid flow in fluidised beds and other multiphase systems. A significant limitation of CFD-DEM is the feasibility of the realistic simulation of large numbers of particles. Coarse-graining (CG) approaches, through which groups of multiple individual particles are represented by single, larger particles, can substantially reduce the total number of particles while maintaining similar system dynamics. As these three CG models have not previously been compared, there remains some debate, however, about the best practice in the application of CG in CFD-DEM simulations. In this paper, we evaluate the performance of three typical CG methods based on simulations of a bubbling fluidised bed. This is achieved through the use of a numerical validation framework, which makes full use of the high-resolution 3D positron emission particle tracking (PEPT) measurements to rigorously validate the outputs of CFD-DEM simulations conducted using various different coarse-graining models, and various different degrees of coarse-graining. The particle flow behaviours in terms of the particle occupancy field, velocity field, circulation time, and bubble size and velocity, are comprehensively analysed. It is shown that the CG simulation starts to fail when the size ratio between the bed chamber and the particles decreases to approximately 20. It is also observed, somewhat surprisingly, that the specific CG approach applied to interparticle contact parameters does not have a substantial effect on the simulation results for the bubbling bed simulations across a wide range of CG factors.

关键词： Coarse-graining Discrete element method Computational fluid dynamics CFD-DEM Positron emission particle tracking(PEPT) Bubbling fluidised bed

Cybersecurity: Identifying the Vulnerability Intensity Function (VIF) and Vulnerability Index Indicator (VII) of a Computer Operating System

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 Information Security 2022年第4期13卷 337-362页

作者： ranju karki chris P. Tsokos Department of Mathematics and Statistics University of South Florida Tampa USA

The objective of the present study is to define two important aspects of the computer operating system concerning the number of its vulnerabilities behavior. We identify the Vulnerability Intensity Function (VIF), and the Vulnerability Index Indicator (VII) of a computer operating network. Both of these functions, VIF and VII are entities of the stochastic process that we have identified, which characterizes the probabilistic behavior of the number of vulnerabilities of a computer operating network. The VIF identifies the rate at which the number of vulnerabilities changes with respect to time. The VII is an important index indicator that conveys the following information about the number of vulnerabilities of Desktop Operating Systems: the numbers are increasing, decreasing, or remaining the same at a particular time of interest. This decision type of index indicator is crucial in every strategic planning and decision-making. The proposed VIF and VII illustrate their importance by using real data for Microsoft windows Operating Systems 10, 8, 7, and Apple MacOS. The results of the actual data attest to the importance of VIF and VII in the cybersecurity problem we are currently facing.

关键词： Cybersecurity Operating Systems Vulnerabilities Stochastic Process Vulnerability Intensity Function Vulnerability Index Indicator

MCSE planning a windows Server 2003 network infrastructure (exam 70-293)

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

丛书名： Mike Meyers' certification passport

2003年

作者： McCain chris Brown Martin C

来源：畅想之星图书光盘版（南... 评论

在线全文

畅想之星图书光盘版（南通市图书馆镜像）

学校读者我要写书评

暂无评论

windows CE权威指南版

基于ArM9与Wince的工业机器人示教装置设计与开发

丛书名：嵌入系统编程丛书

2001年

作者：（美）chris Muench 精英科技译

本书共分为三个部分。第一部分主要讲述一些准备设置工作和windows CE的基础知识；第二部分为windows CE详解，介绍了用户界面、存储、远程连接、声音和图像等方面；第三部分为附录，提供了一些问题解答、术语表及使用技巧等。

ISBN: (纸本)7508306228

关键词：窗口软件程序设计

来源：畅想之星图书光盘版（南... 评论

在线全文

畅想之星图书光盘版（南通市图书馆镜像）

学校读者我要写书评

暂无评论

机床与液压 2016年第3期44卷 5-9,23页

作者：覃宇勒黄振峰毛汉领广西大学机械工程学院广西南宁530004

在工业机器人的应用过程中,示教装置已经成为机器人控制系统中不可或缺的一部分,其操作体验和性能的优劣直接关系到工业机器人使用效果。所设计的示教装置硬件结构和操作系统分别采用了基于ArM9的rISC ArM926EJ处理器和windows CE 5.0... 详细信息

在工业机器人的应用过程中,示教装置已经成为机器人控制系统中不可或缺的一部分,其操作体验和性能的优劣直接关系到工业机器人使用效果。所设计的示教装置硬件结构和操作系统分别采用了基于ArM9的rISC ArM926EJ处理器和windows CE 5.0操作系统,整体外壳采用3D快速成形打印技术研制。应用程序的开发环境为Microsoft Visual studio2008,以MFC为图形界面开发工具,采用串口通信实现示教装置与主控制器之间通信。该装置符合人体工程学,人机界面友好,运行稳定,满足控制的需要,具有较强的实用性。

关键词：示教装置 Wince嵌入式系统 3D打印串口通信数据通信协议

Modeled Implications of Global Warming Conditions on Precipitation Totals in Valley and Highland Areas of Nigeria

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

American Journal of Climate Change 2023年第3期12卷 489-503页

作者： Johnson Orfega Mage rhoda Mojisola Olanrewaju Ifeanyi chris Onwuadiochi Department of Geography Benue State University Makurdi Nigeria Department of Geography and Environmental Management University of Ilorin Ilorin Nigeria Department of Geography and Meteorology Nnamdi Azikiwe University Awka Nigeria

Global temperature has been increasing causing differences in precipitation response in different physiographic regions as feedback mechanism. The aim of this work is to model the implications of the global warming conditions on precipitation occurrences in the valley and highland areas of Nigeria. Harmonic analysis on the average monthly rainfall observations was performed for 56 years (1961-2016) using the Turbo Pascal for windows programming language in order to implement the computation. This was carried out by fitting a periodic function of sinusoidal character to enhance the determination of the contribution of each harmonic, the amplitude of each harmonic and the time at which each harmonic is maximum. The result of harmonic plots of the grand average monthly rainfall for the valley area of Makurdi and highland area of Jos shows that there exists a similarity in the trend of variations of harmonic series plots of the data as either plots exhibit single rainfall maxima or peak, meaning that rainfall patterns are mono-modal in nature. Modeled result of average monthly rainfall for the valley area of Makurdi shows an increase in rainfall occurrences from the month of January to August but a decrease from September to December, meaning an expectation of more rains immediately after onsets and lesser rains before cessations. The modeled result for the highland area of Jos however shows a decrease in the occurrence of rainfall in the months of January and February but an increase from the month of March to December. The implication is that there will be water deficiency for late crops and aquifer recharge in the valley areas while highland areas will experience delayed onset of agricultural calendar. The study recommends timely release and adherence to weather/climate forecasts.

关键词： Physiographic regions Harmonics rainfall Patterns

windows WDM设备驱动程序开发指南

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论