检索结果-内蒙古大学图书馆

Higher-Order I-Section Beam analysis Using recursive analysis

TRANSACTIONS OF THE KOREAN SOCIETY OF MECHANICAL ENGINEERS A 2023年第9期47卷 701-720页

作者： Choi, Soomin Kyungpook Natl Univ Sch Mech Engn Kyungpook South Korea

To predict the responses of I-section beams (that is, displacements and stresses) under bending loads including end effects, a one-dimensional higher-order beam analysis requires numerous cross-sectional deformation modes. In this study, we establish a new recursive analysis method for I-section beams that can provide as many sectional deformation modes as required. In contrast to earlier studies that calculate the modes numerically by discretizing the cross-section using beam / shell elements, the proposed method derives the modes analytically. Hence, the shape functions of the resulting modes are written in closed form and are thus available irrespective of the cross-sectional dimensions of the I-section beams. Additionally, the resulting recursive relations between sectional shape functions allow us to establish explicit stress-generalized force relations applicable for higher-order I-section beam analysis. To check the validity of the proposed method, several examples of interpreting displacements and stresses of I-section beams are considered.

关键词： I-Section Beam Higher-Order Beam Theory Cross-Sectional Deformation Sectional Shape Function recursive analysis

来源：评论

学校读者我要写书评

暂无评论

Experimental and numerical study on the horizontal-vertical pneumatic conveying system with pulse excitation flow based on POD and recursive analysis

引用

ADVANCED POWDER TECHNOLOGY 2022年第4期33卷 103524-103524页

作者： Tu, PanPan Yan, Fei Jiangsu Univ Sci & Technol Sch Mech Engn Zhenjiang 212000 Peoples R China

To solve the problem of energy loss during pneumatic conveying, a new energy-saving method of pneumatic transportation, pulse excitation flow, is proposed and applied to the transportation of petroleum coke. Firstly, the minimum pressure drop velocity of petroleum coke transported by pulse excitation flow is obtained through experimental research, and then the energy-saving mechanism of pulse excitation flow is explored through CFD-EDM coupling. The experimental results show that the energy loss coefficient of pulse excitation flow is reduced by 12.6% compared with axial flow. The numerical results show that the pulse excitation flow will produce alternating positive and negative vortices, and using the pulse excited flow conveying can make the particles enter the suspension region 6D earlier and reduce the energy loss, which further indicates that the gas-solid coupling effect of the pulsed excitation flow is more conducive to the dispersion and acceleration of the particles compared with axial flow.(c) 2022 The Society of Powder Technology Japan. Published by Elsevier B.V. and The Society of Powder Technology Japan. All rights reserved.

关键词： Pneumatic conveying CFD-EDM Pulse excitation flow Proper orthogonal decomposition recursive analysis

来源：评论

学校读者我要写书评

暂无评论

Consistent higher-order beam theory for thin-walled box beams using recursive analysis: Edge-bending deformation under doubly symmetric loads

引用

ENGINEERING STRUCTURES 2020年第0期206卷 110129-000页

作者： Choi, Soomin Kim, Yoon Young Seoul Natl Univ Soft Robot Res Ctr Gwanak Ro 1 Seoul 08826 South Korea Seoul Natl Univ Sch Mech & Aerosp Engn Gwanak Ro 1 Seoul 08826 South Korea

Thin-walled box beams generally exhibit complex sectional deformations that are not significant in solid beams. Accordingly, a higher-order beam theory suitable for the analysis of thin-walled box beams should include degrees of freedom representing sectional deformations. In a recent study, a recursive analysis method to systematically derive sectional membrane deformations has been proposed to establish a consistent higher-order beam theory. In this study, another recursive analysis method is proposed that is suitable for the closed-form derivation of new sectional bending deformations representing the bending of edges (or walls) of the cross-section shown in a box beam under doubly symmetric loads. A consistent 1D higher-order beam theory appropriate to include these additional deformation modes as beam degrees of freedom is also established. The proposed theory provides explicit formulas that relate stresses to generalized forces including self-equilibrated forces such as bimoments. Furthermore, sectional modes are hierarchically derived so that the level of solution accuracy can be effectively and systematically controlled. Thus, the accuracy for static displacement/stress calculations and eigenfrequencies can be adjusted to be fully comparable with plate/shell results. When general doubly symmetric loads are applied to a box beam, the edge membrane modes derived in an earlier study can also be used as additional degrees of freedom besides the edge-bending modes derived in this study. The validity of the proposed beam approach is verified through the analyses of static displacements and stresses as well as eigenfrequencies for free vibration problems.

关键词： Thin-walled box beam Consistent higher-order beam theory recursive analysis Generalized force-stress relation Edge-bending deformation

来源：评论

学校读者我要写书评

暂无评论

Consistent higher-order beam theory for thin-walled box beams using recursive analysis: Membrane deformation under doubly symmetric loads

引用

ENGINEERING STRUCTURES 2019年 197卷 109430-000页

作者： Choi, Soomin Kim, Yoon Young Seoul Natl Univ Soft Robot Res Ctr Gwanak Ro 1 Seoul 08826 South Korea Seoul Natl Univ Sch Mech & Aerosp Engn Gwanak Ro I Seoul 08826 South Korea

We propose a consistent higher-order beam theory in which cross-sectional deformations defining degrees of freedom are derived in the framework consistent with the mechanics of the proposed one-dimensional beam theory. This approach contrasts with earlier methods in which the procedure used to derive sectional deformations and the final beam theory are based on models of different levels. An advantage of the proposed consistent approach is that the generalized force-stress relation even for self-equilibrated forces such as bimoments can now be explicitly written. Also, sectional deformations can be systematically derived in closed form by the recursive and hierarchical approach. Accordingly, the accuracy in both displacement and stress can be adjusted so that obtained results are fully comparable with plate/shell results. We mainly conduct analysis of membrane deformations occurring in thin-walled box beams subjected to doubly symmetric loads such as axially-loaded forces. This case is elaborately chosen to better explain the fundamental concepts of our newly proposed approach. A brief description is also provided to show that these concepts are applicable to other types of loads such as bending and torsion. We confirm the accuracy of the theory proposed here by calculating stress and displacement in several examples.

关键词： Thin-walled box beam Consistent higher-order beam theory recursive analysis Generalized force-stress relation Membrane deformation

来源：评论

学校读者我要写书评

暂无评论

Two-phase Flow Pattern Diagnosis Based on Chaotic recursive Graph and Spectral analysis 41

Two-phase Flow Pattern Diagnosis Based on Chaotic Recursive ...

引用

第41届中国控制会议

作者： Ziqi Cui Chao Tan Hanrui Zhang Xuewei Shi Feng Dong Tianjin Key Laboratory of Process Measurement and Control School of Electrical and Information EngineeringTianjin University

ISBN: (数字)9789887581536

ISBN: (纸本)9781665482561

It is difficult to accurately measure the flow parameters of gas-liquid two-phase flow in horizontal pipe because of its complexity and *** of two-phase flow pattern is helpful to analyze fluid flow state and provide more information for accurate measurement of flow *** this paper,a two-phase flow pattern diagnosis algorithm based on acoustic-electrical data fusion is ***,chaos recursive analysis is performed on the data obtained by electronic resistance tomography(ERT) *** wavelet transform is performed on ERT data and the total energy of wavelet transform is ***,spectrum analysis is used on the ultrasonic Doppler data,and statistical characteristics of spectrum bandwidth and average velocity are *** vector machine(SVM) and K-nearest neighbor were used to distinguish these features objectively,and the recognition accuracy are 88% and 92%.

关键词： Flow patterns ERT Ultrasonic doppler recursive analysis SVM

来源：评论

学校读者我要写书评

暂无评论

Experimental and numerical simulation study of particles flow in the microchannel equipped with fan-shaped rib on sidewall

引用

PARTICUOLOGY 2025年 100卷 45-61页

作者： Yang, Zhenyu Li, Xiaolong Zhang, Weifeng Cai, Tianyi Zhou, Wu Univ Shanghai Sci & Technol Sch Energy & Power Engn Shanghai 200093 Peoples R China Shanghai Key Lab Multiphase Flow & Heat Transfer P Shanghai 200093 Peoples R China

Microchannels are widely used in electronic device cooling due to their efficient heat dissipation performance, but particle deposition is still a major challenge limiting their performance. To design and optimize efficient microfluidic devices, this paper proposes to introduce fan-shaped ribs within the microchannels to reduce particle deposition. The placement of fan ribs of different heights in the microchannel was first experimentally determined, and then the particle motion characteristics were further investigated by numerical simulations. The results show that the fan-shaped ribs can effectively reduce particle deposition and exhibit greater deposition inhibition with increasing rib height. The channel constriction induced by the rib structure promotes the radial diffusion of particles in the downstream, and at the same time significantly enhances the radial component of the particle flow, which is improved by 5.76 %, 7.98 %, and 10.86 %, respectively. In addition, recursive analysis revealed that the incorporation of fan-shaped ribs shifted the particle flow from a homogeneous, periodic mode to a more abrupt diffusion mode, which contributed to the improvement of particle dispersion. This study provides a new strategy without the use of surfactants, which provides a reference for the optimized design of microchannel cooling systems. (c) 2025 Chinese Society of Particuology and Institute of Process Engineering, Chinese Academy of Sciences. Published by Elsevier B.V. All rights are reserved, including those for text and data mining, AI

关键词： Microchannel Fan-shaped rib Particle flow pattern recursive analysis

来源：评论

学校读者我要写书评

暂无评论

Partitioning for "Common but Differentiated" Precise Air Pollution Governance: A Combined Machine Learning and Spatial Econometric Approach

引用

ENERGIES 2022年第9期15卷 3346页

作者： Yi, Yang Wen, Le He, Shan China Univ Geosci Sch Econ & Management Wuhan 430074 Peoples R China Univ Auckland Dept Econ Energy Ctr Auckland 1142 New Zealand Zhumadian Vocat & Tech Coll Sch Econ & Management Zhumadian 463000 Peoples R China

Effective governance of air pollution requires precise identification of its influencing factors. Most existing studies attempt to identify the socioeconomic factors but lack consideration of multidimensional heterogeneous characteristics. This paper fills this long-ignored research gap by differentiating governance regions with regard to multidimensional heterogeneity characteristics. Decision tree recursive analysis combined with a spatial autoregressive model is used to identify governance factors in China. Empirical results show several interesting findings. First, geographic location, administrative level, economic zones and regional planning are the main heterogeneous features of accurate air pollution governance in Chinese cities. Second, significant influencing factors of air pollution in different delineated regions are identified, especially significant differences between coastal and non-coastal cities. Third, the trends of heterogeneity in urban air governance in China are to some extent consistent with national policies. The approach identifies factors influencing air pollution, thus providing a basis for accurate air pollution governance that has wider applicability.

关键词： air pollution air quality index heterogeneity recursive analysis socioeconomic factors

来源：评论

学校读者我要写书评

暂无评论

recursive Markovian analysis for the Occupancy Distribution of M/G/1 Queuing Systems 2

Recursive Markovian Analysis for the Occupancy Distribution ...

引用

2nd International Conference on Engineering and Technology (ICET)

作者： Elshabrawy, Tallal German Univ Cairo New Cairo City Main Entrance AlTagamoa AlKhames Cairo Egypt

ISBN: (纸本)9781479958078

M/G/1 queuing analysis has a critical role in the performance evaluation of different communication systems. Traditional approaches for M/G/1 queuing analysis employ the Laplace transform and are generally used to estimate only the mean and variance of the queue length distribution. These parameters are not adequate for comprehensive assessment of system performance. Furthermore, these techniques occasionally become limited when dealing with the queuing analysis of data-type of traffic that has heavy-tailed service time distributions. In this paper, a one-dimensional embedded Markov model is developed to derive the exact queue length distribution of MlG/1 queues without any restrictions on the type of the service distribution. Transition probabilities of the developed Markov chain are derived with the use of a recursive method. The analytical approach is then applied to derive the queue occupancy distribution of an M/G/1 queuing system with heavy-tailed Weibull distribution service time.

关键词： M/G/1 queues embedded Markov chains recursive analysis Weibull distribution

来源：评论

学校读者我要写书评

暂无评论

Approximately strategyproof tournament rules in the probabilistic setting 12

Approximately strategyproof tournament rules in the probabil...

引用

12th Innovations in Theoretical Computer Science Conference, ITCS 2021

作者： Ding, Kimberly Matthew Weinberg, S. Computer Science Princeton University NJ United States

ISBN: (纸本)9783959771771

We consider the manipulability of tournament rules which map the results of (n 2) pairwise matches and select a winner. Prior work designs simple tournament rules such that no pair of teams can manipulate the outcome of their match to improve their probability of winning by more than 1/3, and this is the best possible among any Condorcet-consistent tournament rule (which selects an undefeated team whenever one exists) [14, 15]. These lower bounds require the manipulators to know precisely the outcome of all future matches. We take a beyond worst-case view and instead consider tournaments which are "close to uniform": the outcome of all matches are independent, and no team is believed to win any match with probability exceeding 1/2+Ε. We show that Randomized Single Elimination Bracket [14] and a new tournament rule we term Randomized Death Match have the property that no pair of teams can manipulate the outcome of their match to improve their probability of winning by more than Ε/3 + 2Ε2/3, for all Ε, and this is the best possible among any Condorcet-consistent tournament rule. Our main technical contribution is a recursive framework to analyze the manipulability of certain forms of tournament rules. In addition to our main results, this view helps streamline previous analysis of Randomized Single Elimination Bracket, and may be of independent interest. © Kimberly Ding and S. Matthew Weinberg.

关键词： Incentive compatibility recursive analysis Social choice theory Tournaments

来源：评论

学校读者我要写书评

暂无评论

A survey of recursive analysis and Moore's notion of real computation

引用

NATURAL COMPUTING 2012年第1期11卷 37-49页

作者： Gomaa, Walid Egypt Japan Univ Sci & Technol Dept Comp Sci & Engn Alexandria Egypt Univ Alexandria Fac Engn Alexandria Egypt

The theory of analog computation aims at modeling computational systems that evolve in a continuous space. Unlike the situation with the discrete setting there is no unified theory of analog computation. There are several proposed theories, some of them seem quite orthogonal. Some theories can be considered as generalizations of the Turing machine theory and classical recursion theory. Among such are recursive analysis and Moore's class of recursive real functions. recursive analysis was introduced by Turing (Proc Lond Math Soc 2(42):230-265, 1936), Grzegorczyk (Fundam Math 42:168-202, 1955), and Lacombe (Compt Rend l'Acad Sci Paris 241:151-153, 1955). Real computation in this context is viewed as effective (in the sense of Turing machine theory) convergence of sequences of rational numbers. In 1996 Moore introduced a function algebra that captures his notion of real computation;it consists of some basic functions and their closure under composition, integration and zero-finding. Though this class is inherently unphysical, much work have been directed at stratifying, restricting, and comparing it with other theories of real computation such as recursive analysis and the GPAC. In this article we give a detailed exposition of recursive analysis and Moore's class and the relationships between them.

关键词： recursive analysis Turing machine GPAC Analog computation Function algebra

来源：评论

学校读者我要写书评

暂无评论

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案：

请选择收藏分类：

通借通还

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：