Diffusion of Bi-Interstitials in the Fe and V BCC Metals Subjected to Different Types of External Loads

2021 ◽  
Vol 122 (11) ◽  
pp. 1081-1087
Author(s):  
D. N. Demidov ◽  
A. B. Sivak ◽  
P. A. Sivak
Keyword(s):  
Bcc Metals ◽  
Different Types ◽  
External Loads

A frequency response function-based updating technique for the finite element model of automotive structures

2008 ◽  
Vol 222 (10) ◽  
pp. 1781-1791 ◽  
Author(s):  
D-C Lee ◽  
C-S Han
Keyword(s):  
Finite Element ◽  
Element Model ◽  
Design Parameters ◽  
External Loading ◽  
Element Analysis ◽  
Automotive Structures ◽  
Different Types ◽  
External Loads ◽  
The Finite Element Model ◽  
Huge Variety

Today's automotive industry uses finite element analysis (FEA) in a huge variety of applications in order to optimize structures and processes before hardware is produced. Efficiencies can be enhanced and margins are reduced because the external loads and structural properties are identified with higher confidence. The accuracy of FEA predictions has become increasingly important and directly influences the competitiveness of a product on the market. Because automotive structures are under dynamic environments, the correlation on the basis of static deformations independent of the mass and damping parameters do not provide a valuable reference from the view of the dynamic characteristics. In this paper, by systematically comparing the results from analytical and experimental analysis techniques, finite element (FE) models can be validated by the deterministic and robust design on the basis of each tolerance of design parameters, and improved so that they can be used with more confidence in further analysis. Making use of different types of test datum, a recommended procedure is to use a sequence of analysis in which mass, stiffness, damping, and external loading are validated and, if necessary, updated.

Reliability Evaluation of Double-Layer Spherical Lattice Shell

2013 ◽  
Vol 405-408 ◽  
pp. 905-908
Author(s):  
Hui Jun Li ◽  
Zheng Zhong Wang
Keyword(s):  
Yield Strength ◽  
Double Layer ◽  
Random Variables ◽  
Sectional Area ◽  
Cross Sectional ◽  
Different Types ◽  
Calculated Effect ◽  
Lattice Shell ◽  
External Loads ◽  
Lattice Shells

Reliability and sensitivity of double-layer spherical lattice shells are extensively investigated, moreover the effect of different types of random variables and different positions of random variables on reliability and sensitivity are also studied in detail. External loads, cross-sectional area and yield strength of members are defined as random variables respectively according to their types and layouts in the lattice shells, and their effects on sensitivity are substantially calculated. Effect of random variables on several performance functions is also studied. Finally, correlations among these performance functions are calculated.

Mobility of Self-Interstitials in FCC and BCC Metals

1998 ◽  
Vol 527 ◽  
Author(s):  
Yu.N. Osetsky ◽  
A. Serra ◽  
V. Priego ◽  
F. Gao ◽  
D.J. Bacon
Keyword(s):  
High Temperature ◽  
Low Temperature ◽  
Diffusion Mechanism ◽  
Three Dimensional ◽  
Stable Configuration ◽  
Interatomic Potentials ◽  
Bcc Metals ◽  
Migration Mechanism ◽  
Different Types ◽  
Diffusion Mechanisms

ABSTRACTDiffusion of self-interstitial atoms (SIAs) has been studied in bcc-Fe and fcc-Cu using molecular dynamics and interatomic potentials of different types. The Fe potentials describe SIA configurations of different stability. The temperature dependence of the SIA diffusion mechanisms is qualitatively similar for both potentials. At high temperature the diffusion is three-dimensional via the <110> dumbbell mechanism. The contribution of one-dimensional mechanism via the <111> crowdion increases when temperature decreases. At low temperature (<300K) the diffusion mechanism depends on the stable configuration of the SIA.In fcc-Cu all the potentials reproduce the same stable configuration, namely the <100> dumbbell. The migration mechanism is mainly a three-dimensional random walk via this dumbbell with small contributions from the <110> crowdion at high temperature and a two-dimensional caging mechanism at low temperature.

scholarly journals CONSTRUCTIVE SOLUTIONS OF VANT LOCATION IN CYLINDRO-PLATE-VANT (CPV) COATING OF BUILDING (CONSTRUCTION)

2019 ◽  
Vol 4 (5) ◽  
pp. 77-89 ◽  
Author(s):  
Э. Кужахметова ◽  
El'vira Kuzhahmetova
Keyword(s):  
Spatial Models ◽  
Middle Part ◽  
Building Construction ◽  
Strain Condition ◽  
Stress Strain ◽  
Flat Slab ◽  
Complex Design ◽  
Different Types ◽  
Zero Gaussian Curvature ◽  
External Loads

The article considers the calculation and spatial models of buildings with cylindrical-slab-guy covering and various constructive arrangement of the guy: radial, fan, parallel-transverse, parallel-longitudinal and longitudinal-transverse (cross). The calculations have been performed using the FEMAP / NX NASTRAN software package (PC), taking into account the geometric nonlinearity of the deformation. The novelty of the research is a combined design of cylindrical-slab-guy covering. This is a complex of different types of coverings, overlapping large spans of buildings: the cylindrical shell of zero Gaussian curvature and the flat slab are located in the middle part; symmetric guy coverings are located at the edges. The aim of the study is to assess the effect of guy system with various arrangement of guys on the stress-strain condition of cylindrical-slab-guy covering. The objective of the study is to provide a comparative analysis of the stress-strain condition of complex design of cylindrical-slab-guy covering and to select the optimal structural solution of the guy system under the same conditions (geometric parameters of the building, external loads and boundary fixings)

The extinction time of a general birth and death process with catastrophes

1986 ◽  
Vol 23 (04) ◽  
pp. 851-858 ◽  
Author(s):  
P. J. Brockwell
Keyword(s):  
Laplace Transform ◽  
Size Distribution ◽  
Sufficient Conditions ◽  
Necessary And Sufficient Conditions ◽  
Death Process ◽  
Extinction Time ◽  
Birth And Death Process ◽  
Different Types ◽  
The Laplace Transform ◽  
Necessary And Sufficient

The Laplace transform of the extinction time is determined for a general birth and death process with arbitrary catastrophe rate and catastrophe size distribution. It is assumed only that the birth rates satisfyλ0= 0,λj&gt; 0 for eachj&gt; 0, and. Necessary and sufficient conditions for certain extinction of the population are derived. The results are applied to the linear birth and death process (λj=jλ, µj=jμ) with catastrophes of several different types.

Differentiating between different forms of moral obligations

2020 ◽  
Vol 43 ◽  
Author(s):  
Rajen A. Anderson ◽  
Benjamin C. Ruisch ◽  
David A. Pizarro
Keyword(s):  
Moral Character ◽  
Moral Obligations ◽  
Different Types

Abstract We argue that Tomasello's account overlooks important psychological distinctions between how humans judge different types of moral obligations, such as prescriptive obligations (i.e., what one should do) and proscriptive obligations (i.e., what one should not do). Specifically, evaluating these different types of obligations rests on different psychological inputs and has distinct downstream consequences for judgments of moral character.

Ultrastructural Investigations of the Contractile Filaments of Amoebae

1974 ◽  
Vol 32 ◽  
pp. 188-189
Author(s):  
P.L. Moore
Keyword(s):  
Cytoplasmic Streaming ◽  
Three Dimensional ◽  
Freeze Fracture ◽  
Amoeboid Movement ◽  
Different Types ◽  
Chemical Conditions ◽  
Complete Interpretation

Previous freeze fracture results on the intact giant, amoeba Chaos carolinensis indicated the presence of a fibrillar arrangement of filaments within the cytoplasm. A complete interpretation of the three dimensional ultrastructure of these structures, and their possible role in amoeboid movement was not possible, since comparable results could not be obtained with conventional fixation of intact amoebae. Progress in interpreting the freeze fracture images of amoebae required a more thorough understanding of the different types of filaments present in amoebae, and of the ways in which they could be organized while remaining functional.The recent development of a calcium sensitive, demembranated, amoeboid model of Chaos carolinensis has made it possible to achieve a better understanding of such functional arrangements of amoeboid filaments. In these models the motility of demembranated cytoplasm can be controlled in vitro, and the chemical conditions necessary for contractility, and cytoplasmic streaming can be investigated. It is clear from these studies that “fibrils” exist in amoeboid models, and that they are capable of contracting along their length under conditions similar to those which cause contraction in vertebrate muscles.

Study of the Molecular Architecture of Keratin Filaments by Electron Microscopy

1982 ◽  
Vol 40 ◽  
pp. 118-119
Author(s):  
U. Aebi ◽  
P. Rew ◽  
T.-T. Sun
Keyword(s):  
Electron Microscopy ◽  
Structural Organization ◽  
Cell Types ◽  
Structural Features ◽  
Molecular Architecture ◽  
The Past ◽  
Keratin Filaments ◽  
Different Types ◽  
10 Nm Filaments ◽  
Different Cell Types

Various types of intermediate-sized (10-nm) filaments have been found and described in many different cell types during the past few years. Despite the differences in the chemical composition among the different types of filaments, they all yield common structural features: they are usually up to several microns long and have a diameter of 7 to 10 nm; there is evidence that they are made of several 2 to 3.5 nm wide protofilaments which are helically wound around each other; the secondary structure of the polypeptides constituting the filaments is rich in ∞-helix. However a detailed description of their structural organization is lacking to date.

Field-Ion Microscopy of BCC Metals: A Study of Image Differences and Topographical Variations

1973 ◽  
Vol 31 ◽  
pp. 114-115
Author(s):  
O. T. Inal ◽  
L. E. Murr
Keyword(s):  
Liquid Nitrogen ◽  
Liquid Nitrogen Temperature ◽  
Surface Atom ◽  
Image Brightness ◽  
Field Ion Microscopy ◽  
Topographic Features ◽  
Bcc Metals ◽  
Electron Orbital ◽  
Ion Microscopy ◽  
Field Ion Microscope

When sharp metal filaments of W, Fe, Nb or Ta are observed in the field-ion microscope (FIM), their appearance is differentiated primarily by variations in regional brightness. This regional brightness, particularly prominent at liquid nitrogen temperature has been attributed in the main to chemical specificity which manifests itself in a paricular array of surface-atom electron-orbital configurations.Recently, anomalous image brightness and streaks in both fcc and bee materials observed in the FIM have been shown to be the result of surface asperities and related topographic features which arise by the unsystematic etching of the emission-tip end forms.

A New Defect in Polyethylene Single Crystals

1973 ◽  
Vol 31 ◽  
pp. 70-71
Author(s):  
E. L. Thomas ◽  
S. L. Sass
Keyword(s):  
Single Crystals ◽  
Screw Dislocation ◽  
Small Distance ◽  
Dipole Model ◽  
Dislocation Dipole ◽  
Chain Folding ◽  
Black And White ◽  
Polymer Crystal ◽  
Different Types

In polyethylene single crystals pairs of black and white lines spaced 700-3,000Å apart, parallel to the [100] and [010] directions, have been identified as microsector boundaries. A microsector is formed when the plane of chain folding changes over a small distance within a polymer crystal. In order for the different types of folds to accommodate at the boundary between the 2 fold domains, a staggering along the chain direction and a rotation of the chains in the plane of the boundary occurs. The black-white contrast from a microsector boundary can be explained in terms of these chain rotations. We demonstrate that microsectors can terminate within the crystal and interpret the observed terminal strain contrast in terms of a screw dislocation dipole model.

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