Shocks and energy dissipation in inviscid fluids: a question posed by Lord Rayleigh

1997 ◽  
Vol 347 ◽  
pp. 375-380 ◽  
Author(s):  
JAMES E. BROADWELL
Keyword(s):  
Energy Dissipation ◽  
Turbulent Flows ◽  
Compression Wave ◽  
Inviscid Fluid ◽  
One Dimensional ◽  
Inviscid Fluids ◽  
Relationship Of ◽  
The Relationship

Lord Rayleigh argued that after a discontinuity develops in a one-dimensional compression wave in an ideal inviscid fluid some sort of motion must continue. Arguments are given in support of this view and a suggestion is made as to what that motion might be. The relationship of this motion to that proposed by Onsager for incompressible inviscid turbulent flows is discussed.

scholarly journals Estimation for Two-Dimensional Nonsymmetric Coherently Distributed Source in L-Shaped Arrays

2018 ◽  
Vol 2018 ◽  
pp. 1-16
Author(s):  
Tao Wu ◽  
Zhenghong Deng ◽  
Qingyue Gu ◽  
Jiwei Xu
Keyword(s):  
Expectation Maximization ◽  
Two Dimensional ◽  
Signal Distribution ◽  
Distributed Source ◽  
One Dimensional ◽  
Least Squares Estimators ◽  
Iterative Calculation ◽  
Symmetric Source ◽  
Relationship Of ◽  
The Relationship

We explore the estimation of a two-dimensional (2D) nonsymmetric coherently distributed (CD) source using L-shaped arrays. Compared with a symmetric source, the modeling and estimation of a nonsymmetric source are more practical. A nonsymmetric CD source is established through modeling the deterministic angular signal distribution function as a summation of Gaussian probability density functions. Parameter estimation of the nonsymmetric distributed source is proposed under an expectation maximization (EM) framework. The proposed EM iterative calculation contains three steps in each cycle. Firstly, the nominal azimuth angles and nominal elevation angles of Gaussian components in the nonsymmetric source are obtained from the relationship of rotational invariance matrices. Then, angular spreads can be solved through one-dimensional (1D) searching based on nominal angles. Finally, the powers of Gaussian components are obtained by solving least-squares estimators. Simulations are conducted to verify the effectiveness of the nonsymmetric CD model and estimation technique.

Mechanical Behavior and Failure Patterns of SMA Structural Functional Materials

2013 ◽  
Vol 591 ◽  
pp. 159-163
Author(s):  
Huai Liang Zhu ◽  
Li Feng Yu ◽  
Si Hui Liang ◽  
Chao Qun Ni
Keyword(s):  
Energy Dissipation ◽  
Ductile Failure ◽  
Functional Materials ◽  
Experimental Methods ◽  
Dissipation Factor ◽  
Mechanical Behaviors ◽  
Failure Patterns ◽  
Niti Sma ◽  
Relationship Of ◽  
The Relationship

This paper presents an approach to investigate the mechanical properties and failure patterns of shape memory alloy (SMA) by experimental methods. Tests were carried out under the conditions of uniaxial tension, cycling loading and impact-tension respectively. The mechanical behaviors of NiTi SMA such as the relationship of stress-stain, super-elasticity, high damping, energy dissipation and tension-shock toughness are discussed in detail. In addition, the destroy patterns of SMA materials are analyzed for varying condition of testing. Whether ductile failure or brittle fracture is decided to do much with the testing styles and strain rate of materials. It is shown that with the large restoring deformation, higher energy dissipation factor and tension-shock toughness, so NiTi SMA structural functional materials are very suitable for vibration control in engineering.

A New Type of Hybrid-Passive-Damper

2010 ◽  
Vol 163-167 ◽  
pp. 4367-4372
Author(s):  
Ai Rong Liu ◽  
Qi Cai Yu ◽  
Yuan Yao ◽  
Yu Zhu Guo
Keyword(s):  
Energy Dissipation ◽  
Damping Ratio ◽  
Loading Frequency ◽  
Vibration Period ◽  
Equivalent Damping ◽  
Passive Damper ◽  
New Type ◽  
Energy Dissipation Capacity ◽  
Relationship Of ◽  
The Relationship

This paper investigated the superelasticity and hysteresis characteristics of TiNi shape memory alloy ( SMA ) wire at room temperature, then the mechanical parameters of which were obtained. Based on the TiNi SMA wire and a purchased viscous damper, a new type of hybrid-passive-damper was designed and developed. Experiments were performed in order to validate the relationship of loading frequency and characteristic parameters such as energy dissipation capacity, equivalent damping ratio and equivalent stiffness. Experimental results show that hybrid-passive-damper designed in this paper has excellent energy dissipation capacity and is suitable for the vibration control of structures with long vibration period.

scholarly journals The two-spin model of a tracking chamber: a phase-space perspective

2021 ◽  
Author(s):  
Luigi Barletti
Keyword(s):  
Phase Space ◽  
Spin Model ◽  
Space Representation ◽  
Dimensional Model ◽  
Wigner Matrix ◽  
One Dimensional ◽  
Classical Localization ◽  
Relationship Of ◽  
The Relationship ◽  
Phase Space Representation

AbstractWe study the dynamics of classical localization in a simple, one-dimensional model of a tracking chamber. The emitted particle is represented by a superposition of Gaussian wave packets moving in opposite directions, and the detectors are two spins in fixed, opposite positions with respect to the central emitter. At variance with other similar studies, we give here a phase-space representation of the dynamics in terms of the Wigner matrix of the system. This allows a better visualization of the phenomenon and helps in its interpretation. In particular, we discuss the relationship of the localization process with the properties of entanglement possessed by the system.

scholarly journals FORMS OF ETHNIC IDENTITY AND STRATEGIES OF INTERETHNIC INTEGRATION OF YOUNG PEOPLE IN THE URBAN COMMUNITY. ANALYSIS OF THE RESULTS OF THE STUDY

2021 ◽  
pp. 85-103
Author(s):  
Olga Persidskaya
Keyword(s):  
Ethnic Identity ◽  
Young People ◽  
Urban Community ◽  
Community Analysis ◽  
Sociological Study ◽  
One Dimensional ◽  
Research Results ◽  
Interethnic Interaction ◽  
Relationship Of ◽  
The Relationship

The article provides an analysis of the results of a sociological study conducted in the form of interviews with Novosibirsk residents aged 14 to 19 years. The study was aimed at identifying the forms of ethnic identity in modern youth and the relationship of these forms with the strategies of interethnic integration. It is shown that different combinations of indicators of the severity and valence of ethnic identity form a set of forms of ethnic identity. This allows us to get away from a one-dimensional interpretation of this phenomenon. The identified forms of ethnic identity differ both in the content of what is invested in the understanding of one's own ethnic identity and in the choice of strategies for interethnic interaction. Based on the analysis of the research results, three forms of ethnic identity are described: pronounced, nominal and distant. It is shown that an intercultural and culturally oriented strategy of interethnic interaction corresponds to a pronounced form of ethnic identity, and an omniculturalism to a distant form.

scholarly journals GEODYNAMICS

GEODYNAMICS ◽  
2011 ◽  
Vol 2(11)2011 (2(11)) ◽  
pp. 155-157
Author(s):  
B. Ladanivskyy ◽  
◽  
Keyword(s):  
Transfer Function ◽  
Field Source ◽  
One Dimensional ◽  
Conductivity Model ◽  
The Earth ◽  
Mantle Conductivity ◽  
The One ◽  
Relationship Of ◽  
The Relationship ◽  
Source Structure

The regional magneto-variational sounding method (aka Z/H method) was used for estimation of the Earth's mantle conductivity model at the Panagurishte (PAG) observatory region. A magneto-variational transfer function is calculated on the base of the relationship of vertical to horizontal geomagnetic field spectra components recorded on the Earth surface and priori assumptions about a field source structure. Inversions of the transfer function allow to obtain the one dimensional conductivity model.

Three‐dimensional velocity profile inversion from finite‐offset scattering data

Geophysics ◽  
1981 ◽  
Vol 46 (6) ◽  
pp. 837-842 ◽  
Author(s):  
S. Raz
Keyword(s):  
Velocity Profile ◽  
Three Dimensional ◽  
Scattering Data ◽  
One Dimensional ◽  
Velocity Variations ◽  
Profile Inversion ◽  
Relationship Of ◽  
The Relationship

The reconstruction of three‐dimensional (3-D) velocity variations from finite‐offset scattering data is formulated. Reduction to the limiting cases of zero and small offset distances as well as the case of one‐dimensional (1-D) stratification is given. An inherent increase in complexity is cited and interpreted. The relationship of the proposed inversion to the F-K migration is discussed.

scholarly journals Research on the Fundamental Principles and Characteristics of Correspondence Function

2015 ◽  
Vol 2015 ◽  
pp. 1-15
Author(s):  
Xiangru Li ◽  
Guanghui Wang ◽  
Q. M. Jonathan Wu
Keyword(s):  
Dimensional Space ◽  
Search Space ◽  
Parametric Model ◽  
One Dimensional ◽  
Correct Point ◽  
Matrix Similarity ◽  
Vector Valued Functions ◽  
Relationship Of ◽  
The Relationship ◽  
Vector Valued

The correspondence function (CF) is a concept recently introduced to reject the mismatches from given putative correspondences. The fundamental idea of the CF is that the relationship of some corresponding points between two images to be registered can be described by a pair of vector-valued functions, estimated by a nonparametric regression method with more flexibility than the normal parametric model, for example, homography matrix, similarity transformation, and projective transformations. Mismatches are rejected by checking their consistency with the CF. This paper proposes a visual scheme to investigate the fundamental principles of the CF and studies its characteristics by experimentally comparing it with the widely used parametric model epipolar geometry (EG). It is shown that the CF describes the mapping from the points in one image to their corresponding points in another image, which enables a direct estimation of the positions of the corresponding points. In contrast, the EG acts by reducing the search space for corresponding points from a two-dimensional space to a line, which is a problem in one-dimensional space. As a result, the undetected mismatches of the CF are usually near the correct corresponding points, but many of the undetected mismatches of the EG are far from the correct point.

Nonlinear Ultrasonic Properties of Stress in 2024 Aluminum

2017 ◽  
Vol 1142 ◽  
pp. 371-377 ◽  
Author(s):  
Hong Juan Yan ◽  
Feng Bin Liu ◽  
Qin Xue Pan
Keyword(s):  
Yield Strength ◽  
Nonlinear Coefficient ◽  
Small Strain ◽  
Ultrasonic Waves ◽  
Testing System ◽  
Third Order ◽  
One Dimensional ◽  
Nonlinear Ultrasonic ◽  
Relationship Of ◽  
The Relationship

Perturbation method is used to resolve one-dimensional wave equation under the assumption of small strain conditions. The relationship of the second order relative nonlinear coefficients (SORNC) β', the third order relative nonlinear coefficient (TORNC) δ' as the functions of fundamental and harmonic amplitudes is determined. The specimens are loaded from-200 MPa to 320 MPa at increments of 40 MPa by the electron universal testing machines. The SORNC β' and TORNC δ' are detected by the nonlinear ultrasonic testing system when ultrasonic waves propagate in the specimens. Results show that the relative nonlinear coefficients increase with the stress. The SORNT β' is approximately linear with the stress when stress is lower than 84.6% of the yield strength. The TORNC δ' is approximately linear with the stress when stress is lower than 76.9% of the yield strength.

Sign in / Sign up

Export Citation Format

Share Document