scholarly journals Jordan eliminations in bar system analysis with changes in design model

2021 ◽  
Vol 23 (1) ◽  
pp. 96-104
Author(s):  
D. N. Pestsov
Keyword(s):  
Cross Sections ◽  
System Analysis ◽  
Design Model ◽  
Elimination Method ◽  
Resolvent Equations ◽  
Special Case ◽  
Internal Connections

The article discusses the use of the Jordan elimination method for solving the system of resolvent equations when analyzing the bar systems. The use of the Jordan elimination method makes it possible to determine the forces in cross-sections of bars and displacements of the system units in the case of changes in the design model of the system without the solution of new resolvent equations at each change. Changes in the design model indicate the introduction or removal of the support or internal connections, changes in the stiffness parameters of elements of statically indeterminate systems, and others. The Jordan elimination method is used for a simple statically indeterminate beam, which is a special case of the bar system.

Design criteria for insulation materials applied in timber frame assemblies

2018 ◽  
Vol 9 (3) ◽  
pp. 252-263 ◽  
Author(s):  
Mattia Tiso ◽  
Alar Just
Keyword(s):  
Cross Sections ◽  
Fire Resistance ◽  
Design Methodology ◽  
Research Study ◽  
Design Model ◽  
Insulation Material ◽  
Content Type ◽  
Insulation Materials ◽  
Timber Frame ◽  
Improved Design

Purpose Insulation materials’ contribution to the fire resistance of timber frame assemblies may vary considerably. At present, Eurocode 5 provides a model for fire design of the load-bearing function of timber frame assemblies with cavities completely filled with stone wool. Very little is known about the fire protection provided by other insulation materials. An improved design model which has the potential to consider the contribution of any insulation material has been introduced by the authors. This paper aims to analyze the parameters that describe in a universal way the protection against the charring given by different insulations not included in Eurocode 5. Design/methodology/approach A series of model-scale furnace tests of floor specimens for three different insulation materials were carried out. An analysis on the charring depth of the residual cross-sections was conducted by means of a resistograph device. Findings The study explains the criteria and procedure followed to derive the coefficients for the improved design model for three insulations involved in the study. Originality/value This research study involves a large experimental work which forms the basis of the proposed design model. This study presents an important step for fire resistance calculations of timber frame assemblies.

Phase Distribution Mechanisms in Turbulent Two-Phase Flow in Channels of Arbitrary Cross Section

1981 ◽  
Vol 103 (4) ◽  
pp. 583-589 ◽  
Author(s):  
D. A. Drew ◽  
R. T. Lahey
Keyword(s):  
Cross Sections ◽  
Two Phase Flow ◽  
Phase Distribution ◽  
Bubbly Flow ◽  
Arbitrary Cross Section ◽  
Phase Flow ◽  
Two Phase ◽  
Void Distribution ◽  
Special Case ◽  
Turbulent Two Phase Flow

An analytical model for the phase distribution mechanisms in fully developed turbulent two-phase flow in channels of arbitrary cross sections has been derived. The model has been applied to the special case of cylindrical pipe flow, and compared with existing data. It has been found that, for bubbly flow, it is the distribution of the liquid phase turbulence which determines the void distribution. Furthermore, the void distribution depends on the anisotropic nature of the turbulent two-phase flow.

scholarly journals Stress Resultants and Out-of-Plane Deformations in Stiff Rings Attached to Elastic Cylinders and Subject to Concentrated Loads

1971 ◽  
Vol 93 (3) ◽  
pp. 835-844 ◽  
Author(s):  
Bernard W. Shaffer ◽  
Eric E. Ungar
Keyword(s):  
Cross Sections ◽  
Bending Moment ◽  
Elastic Cylinder ◽  
Concentrated Force ◽  
Direction Parallel ◽  
Out Of Plane ◽  
Elastic Cylinders ◽  
Special Case ◽  
Radial Axis ◽  
Plane Deformations

Expressions are derived which give the internal loads and deformations of a relatively stiff ring which is mounted on an elastic cylinder. Three basic types of loads acting on the ring are considered: a concentrated force acting in the direction parallel to the axis of the cylinder, a bending moment acting about a radial axis, and a bending moment acting about a tangential axis. The entire problem is first analyzed for the general case in which the centers of twist of the ring cross sections do not coincide with the mid-surface of the cylinder, and then also developed for the special case where these do coincide. An illustrative example is presented which gives an indication of the effect of the lack of coincidence of the centers of twist of the ring and the cylinder mid-surface.

Simplification of Hydraulic Line Dynamics by Use of Infinite Products

1964 ◽  
Vol 86 (1) ◽  
pp. 1-8 ◽  
Author(s):  
Rufus Oldenburger ◽  
R. E. Goodson
Keyword(s):  
Cross Sections ◽  
Transmission Lines ◽  
System Analysis ◽  
Transfer Functions ◽  
The United States ◽  
Hydraulic Control ◽  
Electrical Transmission ◽  
Infinite Products ◽  
Power Series Expansions ◽  
Hydraulic Network

In many hydraulic control and other systems the effect of fluid carrying lines is an important factor in system dynamics. Following electrical transmission line technique a hydraulic line between two cross sections is characterized by a four-terminal network with pressure and flow the interacting variables. Use of this four-terminal network in a variety of system problems leads to transfer functions relating pairs of variables in the system, where these transfer functions are transcendental. These transfer functions cause serious mathematical difficulties when employed for the computation of system transients. The standard mathematical technique of using power series expansions fails in that this yields instability in most applications where this instability does not actually occur. In this paper these difficulties are overcome by writing these functions as quotients of infinite products of linear factors. It is shown that it is necessary to keep only a few of these factors to compute transients accurately. The transfer functions are thus replaced by rational approximations. However, in contrast to the classical lumped constant approach to distributed systems the accuracy of the approximation can be seen from the factors directly, facilitating system analysis and synthesis. The technique applies to electrical transmission lines as well as hydraulic pipes. This method yields a technique for automatically smoothing stepwise transient responses obtained in water hammer studies. Good agreement has been obtained between theory and experiment on the four terminal hydraulic network approach. The paper covers the results of the experiments made in the United States to verify the theory.

scholarly journals On the Nonlinear Stability of Inviscid Homogeneous Shear Flows in Sea Straits of Arbitrary Cross Sections

2012 ◽  
Vol 11 (3) ◽  
pp. 31-50
Author(s):  
V Ramakrishnareddy ◽  
M Subbiah
Keyword(s):  
Nonlinear Stability ◽  
Cross Sections ◽  
Shear Flows ◽  
Stability Result ◽  
Finite Amplitude ◽  
Steady Flows ◽  
Stability Theorems ◽  
Sea Straits ◽  
Parallel Shear Flows ◽  
Special Case

In this paper we study the nonlinear stability of steady flows of inviscid homogeneous fluids in sea straits of arbitrary cross sections. We use the method of Arnol'd [1] to obtain two general stability theorems for steady basic flows with respect to finite amplitude disturbances. For the special case of plane parallel shear flows we find a finite amplitude extension of the linear stability result of Deng et al [2]. We also present some examples of basic flows which are stable to finite amplitude disturbances.

Absolute Value Variational Inclusions

2021 ◽  
pp. 121-153
Author(s):  
Muhammad Aslam Noor ◽  
Khalida Inayat Noor
Keyword(s):  
Nonexpansive Mappings ◽  
Monotone Operators ◽  
Alternative Formulation ◽  
Hemivariational Inequalities ◽  
Variational Inclusions ◽  
Existence Of A Solution ◽  
Absolute Value ◽  
Resolvent Equations ◽  
Special Cases ◽  
Special Case

In this paper, we consider a new system of absolute value variational inclusions. Some interesting and extensively problems such as absolute value equations, difference of monotone operators, absolute value complementarity problem and hemivariational inequalities as special case. It is shown that variational inclusions are equivalent to the fixed point problems. This alternative formulation is used to study the existence of a solution of the system of absolute value inclusions. New iterative methods are suggested and investigated using the resolvent equations, dynamical system and nonexpansive mappings techniques. Convergence analysis of these methods is investigated under monotonicity. Some special cases are discussed as applications of the main results.

“Syncope Implies Chaos” in Walking-stick Maps

1977 ◽  
Vol 32 (6) ◽  
pp. 607-613 ◽  
Author(s):  
Otto E. Rössler
Keyword(s):  
Cross Sections ◽  
Monotone Sequence ◽  
Homoclinic Point ◽  
One Dimensional ◽  
Variable Chemical ◽  
The One ◽  
Diagnostic Criterion ◽  
Special Case ◽  
Walking Stick ◽  
Modest Degree

Abstract A number of 3-variable chemical and other systems capable of showing 'nonperiodic' oscillations are governed by walking-stick shaped maps as Poincare cross-sections in state space. The 2-dimensional simple walking-stick diffeomorphism contains the one-dimensional 'single-humped' Li-Yorke map (known to be chaos producing) as a 'degenerate' special case. To prove that chaos is possible also in strictly 2-dimensional walking-stick maps, it suffices to show that a homoclinic point (and hence an in­ finite number of periodic solutions) is possible in these maps. Such a point occurs in the second iterate at a certain (modest) 'degree of overlap' of the walking-stick map. At a slightly larger degree, a 'nonlinear horseshoe map' is formed in the second iterate. It implies presence of periodic trajectories of all even periodicities (at least) in the walking-stick map. At the same time, two major, formerly disconnected, chaotic subregimes merge into one. Diagnostic criterion: presence of 'syncopes' in an otherwise non-monotone sequence of amplitudes.

scholarly journals Correlations between Process and Geometric Parameters in Additive Manufacturing of Austenitic Stainless Steel Components Using 3DPMD

2021 ◽  
Vol 11 (12) ◽  
pp. 5610
Author(s):  
Kevin Hoefer
Keyword(s):  
Additive Manufacturing ◽  
Layer Thickness ◽  
Mass Flow ◽  
Cross Sections ◽  
System Analysis ◽  
Control Variable ◽  
Welding Current ◽  
Scientific Work ◽  
Deposition Process ◽  
Powder Mass

The additive manufacturing of components is characterized by a layered build-up. The stability of the build-up process with regard to the component geometry and the layer thickness is essential for the success of the entire system. A prerequisite for this is the exact knowledge of the interrelationships between the process, construction parameters and the resulting component geometry, respectively. These correlations are determined within the study using the 3D Plasma Metal Deposition Process (3DPMD). For this purpose, the process is first subjected to a system analysis. Possible influencing variables were identified with regard to the question “Which system parameters influence the component geometry?” and then prioritized. Then, the influence of control factors (welding current intensity, welding speed, and powder mass flow) was investigated according to the specifications of the Design of Experiments (DOE) method by means of a full-factorial experimental design and evaluated on the basis of metallographic cross-sections. As a result, it was determined that the system parameter powder mass flow only influences the layer thickness and not the wall thickness and is, therefore, available as a process control variable. In sum, comprehensive knowledge of complex relationships between the control parameters and the component geometry in additive manufacturing using 3DPMD was achieved and forms the basis for further scientific work.

Efficient evaluation of X-ray scattering integrals of Cartesian Gaussian-type functions

1986 ◽  
Vol 42 (4) ◽  
pp. 257-261 ◽  
Author(s):  
M. Barua ◽  
W. Weyrich
Keyword(s):  
Cross Sections ◽  
Wigner Distribution ◽  
Molecular Form ◽  
Form Factors ◽  
Distribution Functions ◽  
Gaussian Type ◽  
X Ray Scattering ◽  
Recurrence Algorithm ◽  
Scattering Cross Sections ◽  
Special Case

A general recurrence algorithm and explicit analytical results are given for scattering integrals with Cartesian Gaussian-type functions, in a form that is necessary for the evaluation of molecular form factors, Wigner distribution functions and Compton scattering cross sections. Overlap integrals are included as a special case.

scholarly journals FLEXIBLE ARCHITECTURAL ENVIRONMENT. SYSTEM ANALYSIS. PROCESS ASPECT

2020 ◽  
pp. 505-509
Author(s):  
V.S. Semenov ◽  
R.Sh. Akbaraliev
Keyword(s):  
Environmental Factors ◽  
System Analysis ◽  
Point Of View ◽  
Structural Elements ◽  
Functional Level ◽  
Analysis Process ◽  
The Aesthetic ◽  
Procedural Aspect ◽  
Color And Light ◽  
Internal Connections

This article examines a flexible architectural environment as a system that can change itsnparameters under the influence of various factors. These changes are motivated by the development or adaptation of the system to external environmental factors. A flexible architectural environment is considered as a system from the point of view of the procedural aspect, which determines changes in the system at various levels, as well as changes in the connections between the internal elements of the system. In this aspect, the internal elements of the system can be identified, with the help of which the flexibility of the architectural environment is achieved. Three levels of change and development of the system are considered in detail: material, functional, and aesthetic. The material and functional level involves changes in the system, which are achieved by structural elements and equipment. The aesthetic level implies changes in the system with elements such as color and light, materials, textures and decor. These groups of elements of the system undergo changes in internal connections, which are formal and aesthetic in nature.

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