找到约10000个结果。
英语原文共 17 页, 人工神经网络的介绍 1引言 人工神经网络(ANN)是一种具有模拟功能的数学模型结构和生物神经网络。人工神经网络的每个基本构建块是人工神经元,即,一个简单的数学模型(函数)。这种模式有三个简单的规则集:乘法,加法和激活。在人工神经入口处的输入加权意味着每个输入值乘以各个权重。在人工神经元的中间部分是总和功能可以概括所有的加权输入和偏差。在人工神经的总和的出口此前加权输入偏置传递槽激活函数,也被称为传递函数(图1)。 图1 人工神经的工作原理。 虽然人工神经的工作原理和一套简单的规则没有什么特别的地方,但当我们开始他们将互连人工神经网络时(图2)就需要这些模型的全部潜力、计算能力来实现。这些人工神经网络使用简单的事实,延伸出来的复杂性只是
英语原文共 7 页, 一种实时微粒监测系统的比较评估 ——室内空气中可吸入颗粒物和可入肺颗粒物重量法 摘要 发达国家的人们约90%的时间在室内,所以室内颗粒物浓度的精确监测对健康风险有重要的作用。直接读取,气溶胶监测装置,奥西里斯粒子监测器(模型2315)和欧洲标准低流量采样器,lvs3(Sven / leckel lvs3)大小选择性口等测量PM10和可入肺颗粒物分数的方法被用来评估可用光和重量方对于室内空气中颗粒物的特性的优良性。同时在博尔镇,塞尔维亚的一个室内环境60个采样周期的24小时样品收集。24小时平均PM10的监测显示奥西里斯监控与lvs3水平密切相关(R2=0.87)并没有表现出统计学显著性偏差。24小时平均可入肺颗粒物监测显示奥西里斯水平与lvs3水平中度相关(R2=0.71),但统计学显著性有偏差。结果表明,监测提
Android Application Fundamentals Android applications are written in the Java programming language. The Android SDK tools compile the code—along with any data and resource files—into an Android package, an archive file with an .apk suffix. All the code in a single .apk file is considered to be one application and is the file that Android-powered devices use to install the application. Once installed on a device, each Android application lives in its own security sandbox: The Android operating system is a multi-user Linux system in which each application is a different user. By default, the system assigns each application a unique Linux user ID (the ID is used only by the system and is unknown to the application). The system sets permissions for all the files in an application so that only the user ID assigned to that application can access them. Each process has its own virtual machine (VM), so an applications code runs in isolation from other applica
英语原文共 4 页, 非晶态合金基配变芯的声学和软磁特性 摘要:一种新的基于合金非晶铁,金属玻璃的2605 HB1M,已开发的配电变压器,改变了传统的合金的化学成分。配电变压器模型的核心基于HB1M和常规的金属玻璃非晶态金属2605 HB1合金进行退火和磁场对其声学和软磁性评估。人们已经发现,以HB1M为基础的核心的A声功率级和激励功率低于HB1为基础的核心。这些变压器的性能改进源于磁各向异性诱导在HB1M比HB1合金更容易实现。 关键词——声学噪声、非晶态合金、磁各向异性、金属玻璃2605 hb1m合金,变压器铁芯。 基本介绍 从配电变压器发出的声音来自于铁芯磁化过程中一系列核心材料的磁致伸缩和绕组的电磁力。一般的,先前的声音是主导。噪音来源于铁芯本身,因此,使用设备时的一个重要因素是考虑到周边环境
英语原文共 10 页, 电源电压畸变对线启动永磁电机能源效率的影响 Colin Debruyne, Peter Sergeant, Stijn Derammelaere, Member, IEEE, Jan J. M. Desmet, Senior Member, IEEE, and Lieven Vandevelde 摘要:类似于标准三相直接联机感应电动机是易受电网电压畸变影响的三相线路启动永磁机器。虽然标准鼠笼式异步电动机以LSPMMs谐波损耗机制简单改编似乎是适当的,本研究将表明,感应电机的谐波损耗计算对于给电源电压失真对LSPMMs的影响作出准确的或者甚至是合理的估计是不合适的。本研究将具体地解决转子诱导谐波电流的相互作用。有限元建模被用来解决电源电压畸变在LSPMMs隔离损耗上的影响。有限元建模(FEM)分配大部分谐波损耗到转子上,并且展现在与第五和第七顺序相同幅度的叠加供给失真之间可以实现转子减少30%损耗和0.5个百分点的整体能源效
英语原文共 16 页, 模糊集理论 H.-J. Zimmermannlowast; 自1965年建立以来,模糊集理论在许多学科、领域中都有着重大进展。可以发现这个理论被应用,例如,在人工智能、计算机计算机科学、医学、工程控制、决策理论、专家系统、逻辑、管理科学、运筹学、模式识别、机器人技术。数学的发展进程已经到了一个很高的标准,但仍然是永无止境的。在这篇综述中,模糊集理论的基本数学框架将被描述,以及这一理论的重要应用和技术。模糊集理论自1992年以来,它的神经网络理论和进化规划领域因“计算智能”或“软计算”而知名。这些领域之间的关系自然变得非常密切。然而,在这篇综述中,我们将主要集中在模糊集理论。我们将会对模糊集理论的应用会和大量实际问题的联系,给出一些参考。即使是一个部分,他们也肯定会超
英语原文共 10 页, 在圆角滚压和弯曲疲劳实验中压敏屈服对曲轴截面应力分布的影响 摘要: 在本文中,首次提出了基于Drucker-Prager屈服函数和最近开发的各向异性硬化规则的对于主动屈服面在加卸载过程的演化方程。用户材料子程序基于各向异性硬化准则和本构关系被编写并输入商业有限元软件ABAQUS。在单轴单调和循环负载条件下,首先进行了一个简单的平面应变的有限元模型的计算。结果表明,各向异性硬化规则在非相关流动规则下把强度微分效应和非对称的闭合磁滞回线铸铁的单轴循环加载试验描述的很好。然后,进行了一个二维平面应变有限元分析的曲轴圆角滚压,随后弯曲被实施。为符合铸铁曲轴的压敏关系,疲劳的关键部位裂纹萌生根据压敏材料的应力分布与曲轴截面弯曲疲劳试验的试验观察一致。 介绍
Budget Management Capacity Of State Government: Issues and Challenges KATHERINE G. Willoughby Georgia State University ABSTRACT: Dramatic events early in the new millennium offer an especially interesting period for consideration of how state governments in the United States have coped. In the years since the September 11 terrorist attack, states have been beset with economic recession, a federal focus on homeland security, and the war in Iraq, as well as debilitating natural disasters. How well have states managed through these fiscal, political, economic, natural, and international storms? This research examines state government budget management capacity as measured by a 50-state survey to understand the challenges faced by states, the advancements made to support best practices in budgeting, and the problems that remain. Findings tease out bright spots—states have worked hard to reach and maintain a long-term budgeting perspective, particularly by improving the acc
Enterprise risk management in financial groups: analysis of risk concentration and default risk Nadine Gatzert · Hato Schmeiser · Stefan Schuckmann Abstract In financial groups, enterprise risk management is becoming increasingly important in controlling and managing the different independent legal entities in the group. The aim of this paper is to assess and relate risk concentration and joint default probabilities of the grouprsquo;s legal entities in order to achieve a more comprehensive picture of a financial grouprsquo;s risk situation. We further examine the impact of the type of dependence structure on results by comparing linear and nonlinear depen- dencies using different copula concepts under certain distributional assumptions. Our results show that even if financial groups with different dependence structures do have the same risk concentration factor, joint default probabilities of different sets of subsidiaries c
MANAGEMENT OF ACCOUNTS RECEIVABLE IN A COMPANY Abstract Accounts receivable management directly impacts the profitability of a company. Firstly, the purpose of the empirical part of the study is to analyze accounts receivable and to demonstrate a correlation between the accounts receivable level and profitability expressed in terms of Retune on Assets (ROA) of sample companies. Secondly, the aim of theoretical research is to explore cost and benefits of changes in credit policy, determine the independent variables which have an impact on net savings and establish a relationship among them in order to develop a new mathematical model for calculating net savings following a revision of credit policy. On the basis of research result, a mathematical model for calculating net savings and following a revision of credit policy, has been developed and with this model a company can consider different credit policies as well as changes in credit policy in order to improve its inco
加微信咨询
加QQ咨询
服务时间:09:00-23:50(周一至周日)