检索结果-内蒙古大学图书馆

European conference on Numerical Mathematics and Advanced Applications, ENUMATH 2017

作者： Chaplain, Mark A. J. Lorenzi, Tommaso Lorz, Alexander Venkataraman, Chandrasekhar School of Mathematics and Statistics University of St Andrews St Andrews United Kingdom Department of Mathematics School of Mathematical and Physical Sciences University of Sussex Brighton United Kingdom Thuwal Saudi Arabia Sorbonne Universités UPMC Univ Paris 06 UMR 7598 Laboratoire Jacques-Louis Lions Paris France

ISBN: (纸本)9783319964140

We present a space- and phenotype-structured model of selection dynamics between cancer cells within a solid tumour. In the framework of this model, we combine formal analyses with numerical simulations to investigate in silico the role played by the spatial distribution of oxygen and therapeutic agents in mediating phenotypic selection of cancer cells. Numerical simulations are performed on the 3D geometry of an in vivo human hepatic tumour, which was imaged using computerised tomography. Our modelling extends our previous work in the area through the inclusion of multiple therapeutic agents, one that is cytostatic, whilst the other is cytotoxic. In agreement with our previous work, the results show that spatial inhomogeneities in oxygen and therapeutic agent concentrations, which emerge spontaneously in solid tumours, can promote the creation of distinct local niches and lead to the selection of different phenotypic variants within the same tumour. A novel conclusion we infer from the simulations and analysis is that, for the same total dose, therapeutic protocols based on a combination of cytotoxic and cytostatic agents can be more effective than therapeutic protocols relying solely on cytotoxic agents in reducing the number of viable cancer cells. © Springer Nature Switzerland AG 2019.

关键词： Cancer cells

来源：评论

学校读者我要写书评

暂无评论

On the preservation of fibre direction during axisymmetric hyperelastic mass-growth of a finite fibre-reinforced tube

引用

JOURNAL OF engineering MATHEMATICS 2018年第1期109卷 173-210页

作者： Soldatos, Kostas P. Univ Nottingham Sch Math Sci Nottingham NG7 2RD England Univ Nottingham Spencer Inst Theoret & Computat Mech Nottingham NG7 2RD England

Several types of tube-like fibre-reinforced tissue, including arteries and veins, different kinds of muscles, biological tubes as well as plants and trees, grow in an axially symmetric manner that preserves their own shape as well as the direction and, hence, the shape of their embedded fibres. This study considers the general, three-dimensional, axisymmetric mass-growth pattern of a finite tube reinforced by a single family of fibres growing with and within the tube, and investigates the influence that the preservation of fibre direction exerts on relevant mathematical modelling, as well on the physical behaviour of the tube. Accordingly, complete sets of necessary conditions that enable such axisymmetric tube patterns to take place are initially developed, not only for fibres preserving a general direction, but also for all six particular cases in which fibres grow normal to either one or two of the cylindrical polar coordinate directions. The implied conditions are of kinematic character but independent of the constitutive behaviour of the growing tube material. Because they hold in addition to and simultaneously with standard kinematic relations and equilibrium equations, they describe growth by an overdetermined system of equations. In cases of hyperelastic mass-growth, the additional information they thus provide enables identification of specific classes of strain energy densities for growth that are admissible and, therefore, suitable for the implied type of axisymmetric tube mass-growth to take place. The presented analysis is applicable to many different particular cases of axisymmetric mass-growth of tube-like tissue, though admissible classes of relevant strain energy densities for growth are identified only for a few example applications. These consider and discuss cases of relevant hyperelastic mass-growth which (i) is of purely dilatational nature, (ii) combines dilatational and torsional deformation, (iii) enables preservation of shape and direction

关键词： Anisotropicmass-growth Axisymmetric mass-growth Elastic-likemass-growth Growth of cylinders and tubes Hyperelastic mass-growth Mass-growth modelling

来源：评论

学校读者我要写书评

暂无评论

modelling rocking behaviour using physics engine simulation 11

Modelling rocking behaviour using physics engine simulation

引用

11th National conference on Earthquake engineering 2018: Integrating Science, engineering, and Policy, NCEE 2018

作者： Ma, Q.T. Parshottam, S. Montalla, M. Dept. of Civil and Environmental Engineering University of Auckland Auckland New Zealand Undergraduate Researcher Dept. of Civil and Environmental Engineering University of Auckland Auckland New Zealand

ISBN: (纸本)9781510873254

The response of a rigid rocking block has been thoroughly studied. From a mathematical modelling standpoint, a pure rocking system is complex, sensitive and sometime chaotic. Because of the complexity, it is generally not practical to develop equation-based models beyond simple three-dimensional rigid blocks or simple idealised structures. Whilst equation-based formulation is valuable and will remain a key method for understanding the fundamental mechanisms behind rocking, a more versatile yet reliable technique is required to model the response of real engineering systems. This study demonstrates the use of physics engine based simulations to model rocking behaviour. Physic engine based simulation is an agent based modelling technique that is sufficiently versatile to simulate complex three-dimensional systems. Importantly, it is also ideologically consistent with fundamental equation-based modelling approaches, such as that of Housner's simple rocking model. This study simulated the response of 102 free rocking rigid blocks and 96 rigid blocks subjected to sinusoidal motion using Blender (an opensource software with an embedded physics engine), and compared the results against classical numerical integration of Housner's equation of motion. The results comprehensively validated that Blender can produce results consistent to Housner's assumption with relatively minimal modelling and computation efforts. As a proof of concept, qualitative results from a masonry wall rocking out-of-plane under base excitation simulation is presented. © Copyright (2018 by Earthquake engineering Research Institute All rights reserved.

关键词： Equations of motion

来源：评论

学校读者我要写书评

暂无评论

mathematical, detailed and parametric modelling for smart spinal orthoses

引用

IOP conference Series: Materials Science and engineering 2021年第1期1018卷

作者： R Murzac C V Doicin M E Ulmeanu T ţurcanu University POLITEHNICA of Bucharest Splaiul Independentei No. 313 District 6 Bucharest Romania

The paper presents a mathematical model and the design details to manufacture a prototype of a smart orthosis for posture correction while sitting on a chair at your office or at home. The global geometry for developing the mathematical model was obtained by direct measuring a human 3D model, developed by scanning one of the authors' body and 3D printing it. Based on the mathematical model, the detailed design for the entire product was performed in accordance with the product architecture. The stages of detailed design for the critical systems within the final assembly are also presented in the paper. The posture correction orthosis must be customized for each user, thus, once the design for the critical components has been validated, a parametric design has been generated to facilitate the manufacturing process. The technical solutions are generated and analysed for a vertebral element of the orthosis, representing the critical component of the product. The vertebral element is subject to mechanical stresses, so that a finite element analysis was performed. The geometry of the component and its material were validated by using FEA on the CAD model of the vertebral element. The further work will include research regarding the changes needed for transforming the orthosis into a medical device for spinal column illnesses.

关键词：

来源：评论

学校读者我要写书评

暂无评论

Semi-analytical models of non-spherical particle shapes using optimised spherical harmonics

引用

CHEMICAL engineering RESEARCH & DESIGN 2018年 137卷 376-394页

作者： Radvilaite, Urte Ramirez-Gomez, Alvaro Rusakeviaus, Dainius Kacianauskas, Rimantas Vilnius Gediminas Tech Univ Dept Informat Syst Sauletekio Av 11 LT-10223 Vilnius Lithuania Tech Univ Madrid Dept Mech Chem & Ind Design Engn Ronda Valencia 3 Madrid 28012 Spain Vilnius Gediminas Tech Univ Dept Appl Mech Sauletekio Av 11 LT-10223 Vilnius Lithuania

Determining particle shape is vital for many industrial processes such as those found in the pharmaceutical, agricultural, and bioenergy industries. With modelling being an essential tool to acquire an understanding of the behaviour of particulates in industrial processes, numerical methods such as DEM are needing numerical solutions to formulate and implement particle shape models that overcome current limitations. Whereas pharmaceutical particles have a regular shape, agricultural and biomass particles often are specific, irregular and non-analytic. Because the diversity of real shapes is enormous, a variety of methods for describing particle shapes currently exist. Recently, the series of spherical harmonics (SHs) has gained much interest through their application in many other fields. This paper focuses on the application of the semi-analytical SH technique and addresses the development of a universal modelling tool for describing different particle shapes using a finite number of SHs. The results obtained from modelling pharmaceutical, agricultural, and biomass particles prove the applicability of SHs to regular as well as irregular shapes. In this regard, their optimised description by minimising the number of non-zero expansion coefficients is demonstrated. To proceed with a smaller number of low-order SHs, surface segmentation is introduced. Sufficient accuracy in the shape description of the particles selected was achieved with less than 16 SHs. (C) 2018 Institution of Chemical Engineers. Published by Elsevier B.V. All rights reserved.

关键词： Spherical harmonics Non-spherical particles Optimisation Surface segmentation mathematical modelling

来源：评论

学校读者我要写书评

暂无评论

Design and Development of In-pipe Inspection Robot for Various Pipe Sizes

引用

IOP conference Series: Materials Science and engineering 2021年第1期1012卷

作者： Atul Gargade Shantipal Ohol Mechanical Engineering Department College of Engineering Pune India.

In-pipe inspection robots are designed to pull out the human role from work load and risky working circumstances. In this paper an in-pipe inspection robot version 2 (IPIR version 2) is presented which composed of two driving leg systems, two supporting leg systems and a connecting body. Novelty of version 2 is its stability and diameter adaptability. Stability of version 2 is enhanced by adding two supporting leg systems in version 1 and diameter adaptability of version 2 is improved by optimizing its spring design. All major components of version 2 are designed safely. Solid modelling of all robot parts and its assembly is carried out in Solidworks 16. mathematical modelling of version 2 is carried by Lagrange's method. A planetary geared DC motor with encoder (IG42E-104K) is used as prime mover of IPIR version 2. This robot has mainly employed aluminium as structural material. To verify the efficacy of driving mechanism, several experiments of version 2 are conducted in horizontal pipes, vertical pipes and couplings of 8 inches to 10 inches diameter range. This IPIR version 2 will be employed for offline visual checking of various pipe components like horizontal pipes, vertical pipes and couplings in water pipelines, gas pipelines and drain pipes etc.

关键词：

来源：评论

学校读者我要写书评

暂无评论

mathematical modelling and Analysis of human Arm as a Triple Pendulum System using Euler - Lagragian Model 2

Mathematical Modelling and Analysis of Human Arm as a Triple...

引用

2nd International conference on engineering for Sustainable World, ICESW 2018

作者： Agarana, Michael C. Akinlabi, Esther T. Department of Mechanical Engineering Science University of Johannesburg South Africa Department of Mathematics Covenant University Nigeria

This study attempts to model the human arm as a dynamical triple pendulum system. The equation of motion of te human arm was obtained using Euler-Lagrange equation. The resulted second order differential equation was solved analytically. Simulated results were presented with the aid of a computer software - Maple. It was observed that the angular displacement values of the three segments are directly proportional to their respective angular acceleration, which is in the modelling and analysis of human arm motion as a multiple pendulum system. Generally, the longer the segments of the human arm the longer it takes to swing back and forth, and the fewer back-and-forth swings there are in a second. © Published under licence by IOP Publishing Ltd.

关键词： Equations of motion

来源：评论

学校读者我要写书评

暂无评论

Developing physical and mathematical models of the water-air mode of gravity drainage network

引用

IOP conference Series: Materials Science and engineering 2021年第1期1015卷

作者： V Orlov S Zotkin Moscow State University of Civil Engineering (National Research University) 129337 Yaroslavskoe shosse 26 Moscow Russia

A physical and mathematical model of the water-air mode of free-flow drainage pipelines has been developed. The solution to the problem of physical modelling of pipeline network functioning is based on the study of the dynamics of changes in the hydraulic and aerodynamic parameters of the system, taking into account the phenomena of heat and mass transfer between liquid and air in the vaulted space of a free-flow pipeline. An algorithm for solving the problem is compiled on the basis of the criteria of hydrodynamic similarity, describing the phenomena of mass transfer as a result of forced air convection by using a mechanical ventilation system above the water surface. Based on the results of applying a special computer-aided calculation program, indicators of the required air exchange rate for effective removal of evaporation (steam) from the vaulted space of a pipeline were determined. As a result of solving the complex problem of studying the water-air mode of free-flow pipeline functioning, the authors compared and analysed the calculated values of the intensity of air exchange produced to remove steam, and to reduce harmful foul-smelling gaseous substances to reach the values of maximum permissible concentrations. The research results are aimed at preventing emissions of gases harmful to human health into the atmospheric air by constructive methods.

关键词：

来源：评论

学校读者我要写书评

暂无评论

Ultra Wideband In Vivo Channel modelling with Respect to Ex Vivo Antenna Location

Ultra Wideband In Vivo Channel Modelling with Respect to Ex ...

引用

European conference on Antennas and Propagation, EuCAP

作者： Muhammad Ilyas Oguz Bayat Muhammad Ali Imran Qammer H. Abbasi School of Engineering and Natural Sciences Altinbas University Istanbul Turkey School of Engineering University of Glasgow Glasgow UK

This article presents mathematical channel modeling for in-vivo communication in terms of the change in the position of the ex-vivo antenna at ultra wideband frequencies. It is shown that the location dependent characteristics are not only dependent on the in-vivo devices placed inside the human body but also the position of ex-vivo devices can impact the channel. Results are calculated using the mathematical model and curve fitting technique by calculation of the Root Mean Square Error (RMSE). The statistics of error prediction among the measured data and the proposed model is RMSE = 14.46 for the right lateral and RMSE = 11.63 for the left lateral respectively. These results will help system designer in accurate link budget calculation for designing enhance implantable devices.

关键词： mathematical model Antennas Numerical models Antenna measurements Ultra wideband technology Implants Torso

来源：评论

学校读者我要写书评

暂无评论

A Computational Study of the Effect of Experience on Problem/Solution Space Exploration in Teams

引用

Proceedings of the Design Society: International conference on engineering Design 2019年第1期1卷 11-20页

作者： Marija Majda Perisic Tomislav Martinec Mario Storga John S Gero University of Zagreb Luleå University of Technology University of North Carolina at Charlotte George Mason University

This paper presents the results of computational experiments aimed at studying the effect of experience on design teams’ exploration of problem-solution space. An agent-based model of a design team was developed and its capability to match theoretically-based predictions is tested. Hypotheses that (1) experienced teams need less time to find a solution and that (2) in comparison to the inexperienced teams, experienced teams spend more time exploring the solution-space than the problem-space, were tested. The results provided support for both of the hypotheses, demonstrating the impact of learning and experience on the exploration patterns in problem and solution space, and verifying the system's capability to produce the reliable results.

关键词： Teamwork Simulation human behaviour in design Agent-based modelling Coevolution

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：