scholarly journals DEVELOPMENT OF RIVER FLOOD ROUTING MODEL USING NON-LINEAR MUSKINGUM EQUATION AND EXCEL TOOL 'GANetXL'

2017 ◽  
Vol 10 (2) ◽  
pp. 214-220
Author(s):  
Briti Sundar Sil ◽  
Angana Borah ◽  
Shubrajyoti Deb ◽  
Biplab Das
Keyword(s):  
Computational Models ◽  
Flood Routing ◽  
Microsoft Excel ◽  
Database Modeling ◽  
Wide Range ◽  
River Flood ◽  
Computational Work ◽  
Non Linear ◽  
Muskingum Routing ◽  
Modeling Data

Flood routing is of utmost importance to water resources engineers and hydrologist. Muskingum model is one of the popular methods for river flood routing which often require a huge computational work. To solve the routing parameters, most of the established methods require knowledge about different computer programmes and sophisticated models. So, it is beneficial to have a tool which is comfortable to users having more knowledge about everyday decision making problems rather than the development of computational models as the programmes. The use of micro-soft excel and its relevant tool like solver by the practicing engineers for normal modeling tasks has become common over the last few decades. In excel environment, tools are based on graphical user interface which are very comfortable for the users for handling database, modeling, data analysis and programming. GANetXL is an add-in for Microsoft Excel, a leading commercial spreadsheet application for Windows and MAC operating systems. GANetXL is a program that uses a Genetic Algorithm to solve a wide range of single and multi-objective problems. In this study, non-linear Muskingum routing parameters are solved using GANetXL. Statistical Model performances are compared with the earlier results and found satisfactory.

scholarly journals DEVELOPMENT OF RIVER FLOOD ROUTING MODEL USING NON-LINEAR MUSKINGUM EQUATION AND EXCEL TOOL 'GANetXL'

2017 ◽  
Vol 10 (2) ◽  
pp. 214-220
Author(s):  
Briti Sundar Sil ◽  
Angana Borah ◽  
Shubrajyoti Deb ◽  
Biplab Das
Keyword(s):  
Computational Models ◽  
Flood Routing ◽  
Microsoft Excel ◽  
Database Modeling ◽  
Wide Range ◽  
River Flood ◽  
Computational Work ◽  
Non Linear ◽  
Muskingum Routing ◽  
Modeling Data

Flood routing is of utmost importance to water resources engineers and hydrologist. Muskingum model is one of the popular methods for river flood routing which often require a huge computational work. To solve the routing parameters, most of the established methods require knowledge about different computer programmes and sophisticated models. So, it is beneficial to have a tool which is comfortable to users having more knowledge about everyday decision making problems rather than the development of computational models as the programmes. The use of micro-soft excel and its relevant tool like solver by the practicing engineers for normal modeling tasks has become common over the last few decades. In excel environment, tools are based on graphical user interface which are very comfortable for the users for handling database, modeling, data analysis and programming. GANetXL is an add-in for Microsoft Excel, a leading commercial spreadsheet application for Windows and MAC operating systems. GANetXL is a program that uses a Genetic Algorithm to solve a wide range of single and multi-objective problems. In this study, non-linear Muskingum routing parameters are solved using GANetXL. Statistical Model performances are compared with the earlier results and found satisfactory.

scholarly journals Estimation of Nonlinear Parameters of Type 6 Hydrological Method in Flood Routing With the Spotted Hyena Optimizer Algorithm (SHO)

2021 ◽  
Author(s):  
Saeid Khalifeh ◽  
Kazem Esmaili ◽  
S. Reza Khodashenas ◽  
Fereshteh Modaresi
Keyword(s):  
Optimization Problems ◽  
Flood Routing ◽  
Spotted Hyena ◽  
Objective Functions ◽  
Linear Type ◽  
Nonlinear Parameters ◽  
Muskingum Model ◽  
River Flood ◽  
Non Linear ◽  
Optimal Values

Abstract In this study, The Spotted hyena optimizer Algorithm (SHO) is used to optimize the parameters of the Non-linear type 6 Muskingum model for flood routing. To evaluate the performance of the SHO in the Non-linear Muskingum models, The Wilson River and the Wye River are applied by many researchers for validation. Moreover, in these studies, the Non-linear Muskingum parameters were estimated by the SHO Algorithm. The SSQ and DPO were considered as objective functions between computed and observed data. According to the results of Wilson river flood, the values of these objective functions for the NL3 model are 128.781, and 0.92 m3/s, and for the NL6 model, are 3.20 and 0.027, respectively. The results of the Wye River flood with the SHO showed that the SSQ and DPO for the NL3 model are 34789.39 and 90.05, and for the NL6 model are 30812.07 and 72.35, respectively. The results show that the proposed algorithm can be applied confidently to estimate the parameter optimal values of the nonlinear Muskingum model. Moreover, this algorithm may be applicable to any continuous engineering optimization problems.

An efficient approach to converting three-dimensional image data into highly accurate computational models

2008 ◽  
Vol 366 (1878) ◽  
pp. 3155-3173 ◽  
Author(s):  
P.G Young ◽  
T.B.H Beresford-West ◽  
S.R.L Coward ◽  
B Notarberardino ◽  
B Walker ◽  
...  
Keyword(s):  
Mesh Generation ◽  
Computational Models ◽  
Three Dimensional ◽  
Image Data ◽  
Model Material ◽  
Imaging Data ◽  
Material Inhomogeneity ◽  
Dimensional Image ◽  
Wide Range ◽  
Impact Modelling

Image-based meshing is opening up exciting new possibilities for the application of computational continuum mechanics methods (finite-element and computational fluid dynamics) to a wide range of biomechanical and biomedical problems that were previously intractable owing to the difficulty in obtaining suitably realistic models. Innovative surface and volume mesh generation techniques have recently been developed, which convert three-dimensional imaging data, as obtained from magnetic resonance imaging, computed tomography, micro-CT and ultrasound, for example, directly into meshes suitable for use in physics-based simulations. These techniques have several key advantages, including the ability to robustly generate meshes for topologies of arbitrary complexity (such as bioscaffolds or composite micro-architectures) and with any number of constituent materials (multi-part modelling), providing meshes in which the geometric accuracy of mesh domains is only dependent on the image accuracy (image-based accuracy) and the ability for certain problems to model material inhomogeneity by assigning the properties based on image signal strength. Commonly used mesh generation techniques will be compared with the proposed enhanced volumetric marching cubes (EVoMaCs) approach and some issues specific to simulations based on three-dimensional image data will be discussed. A number of case studies will be presented to illustrate how these techniques can be used effectively across a wide range of problems from characterization of micro-scaffolds through to head impact modelling.

The attachment length in orificed hollow cathodes

2021 ◽  
Author(s):  
Christopher Wordingham ◽  
Pierre-Yves Taunay ◽  
Edgar Choueiri
Keyword(s):  
Electron Temperature ◽  
Plasma Density ◽  
Hollow Cathode ◽  
Computational Models ◽  
Closed Form Solution ◽  
Form Solution ◽  
Decay Length ◽  
Plasma Density Profile ◽  
Wide Range ◽  
Approximate Boundary Condition

Abstract A first-principles approach to obtain the attachment length within a hollow cathode with a constrictive orifice, and its scaling with internal cathode pressure, is developed. This parameter, defined herein as the plasma density decay length scale upstream of (away from) the cathode orifice, is critical because it controls the utilization of the hollow cathode insert and influences cathode life. A two-dimensional framework is developed from the ambipolar diffusion equation for the insert-region plasma. A closed-form solution for the plasma density is obtained using standard partial differential equation techniques by applying an approximate boundary condition at the cathode orifice plane. This approach also yields the attachment length and electron temperature without reliance on measured plasma property data or complex computational models. The predicted plasma density profile is validated against measurements from the NSTAR discharge cathode, and calculated electron temperatures and attachment lengths agree with published values. Nondimensionalization of the governing equations reveals that the solution depends almost exclusively on the neutral pressure-diameter product in the insert plasma region. Evaluation of analytical results over a wide range of input parameters yields scaling relations for the variation of the attachment length and electron temperature with the pressure-diameter product. For the range of orifice-to-insert diameter ratio studied, the influence of orifice size is shown to be small except through its effect on insert pressure, and the attachment length is shown to be proportional to the insert inner radius, suggesting high-pressure cathodes should be constructed with larger-diameter inserts.

scholarly journals On differential operators and unifying relations for 1-loop Feynman integrands

2021 ◽  
Vol 2021 (10) ◽  
Author(s):  
Kang Zhou
Keyword(s):  
Sigma Model ◽  
Differential Operators ◽  
Linear Sigma Model ◽  
Tree Level ◽  
Maxwell Theory ◽  
Scalar Theory ◽  
Yang Mills ◽  
Loop Level ◽  
Wide Range ◽  
Non Linear

Abstract We generalize the unifying relations for tree amplitudes to the 1-loop Feynman integrands. By employing the 1-loop CHY formula, we construct differential operators which transmute the 1-loop gravitational Feynman integrand to Feynman integrands for a wide range of theories, including Einstein-Yang-Mills theory, Einstein-Maxwell theory, pure Yang-Mills theory, Yang-Mills-scalar theory, Born-Infeld theory, Dirac-Born-Infeld theory, bi-adjoint scalar theory, non-linear sigma model, as well as special Galileon theory. The unified web at 1-loop level is established. Under the well known unitarity cut, the 1-loop level operators will factorize into two tree level operators. Such factorization is also discussed.

scholarly journals Deformation of rockfill in bodies of rockfill dams

2019 ◽  
pp. 5-5
Author(s):  
Mikhail Sainov
Keyword(s):  
Reinforced Concrete ◽  
Deformation Modulus ◽  
Deformation Model ◽  
Observation Data ◽  
Linear Deformation ◽  
Laboratory Test Results ◽  
Wide Range ◽  
Deformation Properties ◽  
Non Linear ◽  
The Impact

Introduction. The main factor determining the stress-strain state (SSS) of rockfill dam with reinforced concrete faces is deformability of the dam body material, mostly rockfill. However, the deformation properties of rockfill have not been sufficiently studied yet for the time being due to technical complexity of the matter, Materials and methods. To determine the deformation parameters of rockfill, scientific and technical information on the results of rockfill laboratory tests in stabilometers were collected and analyzed, as well as field data on deformations in the existing rockfill dams. After that, the values of rockfill linear deformation modulus obtained in the laboratory and in the field were compared. The laboratory test results were processed and analyzed to determine the parameters of the non-linear rockfill deformation model. Results. Analyses of the field observation data demonstrates that the deformation of the rockfill in the existing dams varies in a wide range: its linear deformation modulus may vary from 30 to 500 МPа. It was found out that the results of the most rockfill tests conducted in the laboratory, as a rule, approximately correspond to the lower limit of the rockfill deformation modulus variation range in the bodies of the existing dams. This can be explained by the discrepancy in density and particle sizes of model and natural soils. Only recently, results of rockfill experimental tests were obtained which were comparable with the results of the field measurements. They demonstrate that depending on the stress state the rockfill linear deformation modulus may reach 700 МPа. The processing of the results of those experiments made it possible to determine the parameters on the non-linear model describing the deformation of rockfill in the dam body. Conclusions. The obtained data allows for enhancement of the validity of rockfill dams SSS analyses, as well as for studying of the impact of the non-linear character of the rockfill deformation on the SSS of reinforced concrete faces of rockfill dams.

Non-Linear Dynamic Magneto Electric Effects in Ferromagnetic-Ferroelectric Layered Composites

2013 ◽  
Author(s):  
Satenik Harutyunyan ◽  
Davresh Hasanyan
Keyword(s):  
Vibration Frequency ◽  
Strain Distribution ◽  
Longitudinal Vibration ◽  
Three Dimensional ◽  
Low Frequency ◽  
Structure Design ◽  
Experimental Results ◽  
Physical Parameters ◽  
Wide Range ◽  
Non Linear

A non-linear theoretical model including bending and longitudinal vibration effects was developed for predicting the magneto electric (ME) effects in a laminate bar composite structure consisting of magnetostrictive and piezoelectric multi-layers. If the magnitude of the applied field increases, the deflection rapidly increases and the difference between experimental results and linear predictions becomes large. However, the nonlinear predictions based on the present model well agree with the experimental results within a wide range of applied electric field. The results of the analysis are believed to be useful for materials selection and actuator structure design of actuator in actuator fabrication. It is shown that the problem for bars of symmetrical structure is not divided into a plane problem and a bending problem. A way of simplifying the solution of the problem is found by an asymptotic method. After solving the problem for a laminated bar, formula that enable one to change from one-dimensional required quantities to three dimensional quantities are obtained. The derived analytical expression for ME coefficients depend on vibration frequency and other geometrical and physical parameters of laminated composites. Parametric studies are presented to evaluate the influences of material properties and geometries on strain distribution and the ME coefficient. Analytical expressions indicate that the vibration frequency strongly influences the strain distribution in the laminates, and that these effects strongly influence the ME coefficients. It is shown that for certain values of vibration frequency (resonance frequency), the ME coefficient becomes infinity; as a particular case, low frequency ME coefficient were derived as well.

Rotorcraft control response using linearised and non-linear flight dynamic models with different inflow models

2017 ◽  
Vol 121 (1238) ◽  
pp. 553-575 ◽  
Author(s):  
T. Sakthivel ◽  
C. Venkatesan
Keyword(s):  
Dynamic Model ◽  
Dynamic Models ◽  
Model Identification ◽  
Flight Test ◽  
Step Size ◽  
Response Characteristics ◽  
Wide Range ◽  
Non Linear ◽  
Steady Level ◽  
Control Response

ABSTRACTThe aim of the present study is to develop a relatively simple flight dynamic model which should have the ability to analyse trim, stability and response characteristics of a rotorcraft under various manoeuvring conditions. This study further addresses the influence of numerical aspects of perturbation step size in linearised model identification and integration timestep on non-linear model response. In addition, the effects of inflow models on the non-linear response are analysed. A new updated Drees inflow model is proposed in this study and the applicability of this model in rotorcraft flight dynamics is studied. It is noted that the updated Drees inflow model predicts the control response characteristics fairly close to control response characteristics obtained using dynamic inflow for a wide range of flight conditions such as hover, forward flight and recovery from steady level turn. A comparison is shown between flight test data, the control response obtained from the simple flight dynamic model, and the response obtained using a more detailed aeroelastic and flight dynamic model.

Investigation of neural network and fuzzy inference neural network and their optimization using meta-algorithms in river flood routing

2018 ◽  
Vol 94 (3) ◽  
pp. 1057-1080 ◽  
Author(s):  
Mohammad R. Hassanvand ◽  
Hojat Karami ◽  
Sayed-Farhad Mousavi
Keyword(s):  
Neural Network ◽  
Fuzzy Inference ◽  
Flood Routing ◽  
River Flood

Convergence

2018 ◽  
Author(s):  
Daithí Mac Síthigh
Keyword(s):  
Human Rights ◽  
Public Service ◽  
Audiovisual Media ◽  
On Demand ◽  
European Court ◽  
Wide Range ◽  
Media Services ◽  
Non Linear ◽  
Telecommunications Law

The purpose of this chapter is to explain, in the context of telecommunications law and regulation, the regulation by EU and UK law of audiovisual and radio media services. Overarching principles are found in the Audiovisual Media Services Directive, which takes an approach described as technologically neutral, but established two top-level categories of regulation, for television (or linear) services and on-demand (or non-linear) services. In the case of television services, a wide range of standalone works and comprehensive Sections or chapters on the regulation of broadcasting are available. As such, the focus here (with a view to the interests of readers) is on licensing of content and multiplex services by Ofcom and the handling of complaints about those services, with a bias towards the standard licences for services on cable, satellite, internet, and digital terrestrial platforms, and the regulation of DTT multiplexes and of on-demand services, as opposed to detailed description of the BBC and the commercial public service broadcasters. Indeed, the European Court of Human Rights has regularly found that the regulation of communications infrastructure can have a real impact on the receiving and imparting of information.

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