Determination of geometrical parameters of the diamond gear hones for the finishing of gears

Application of surface and subsurface waves for control of objects with a double-layer structure allows to extend possibilities of diagnostics of their physico-mechanical properties. The purpose of work was to determine conditions and offer recommendations providing measuring of ultrasonic velocity and amplitude of the former modes in protective layers and in basis of object at one-sided access to its surface.The analysis of an acoustic path of a measuring system in relation to ultrasonic evaluation of the objects having the restricted sizes and the protective coating according to velocity data of the surface and subsurface waves propagation is made. On the basis of representations of beam acoustics the dependences connecting a wavelength of the excited surface and subsurface modes, thickness and width of a controlled object, acoustic base of a sounding are defined. There are to provide a condition leveling of the influence of an acoustical noise created by the reflected and accompanying waves on parameters of acoustic signal with the given quantity of oscillations in an impulse.The principle opportunity is shown and conditions for determination of velocity of subsurface body waves in the base material which is under a protective coating layer are established. For these purposes on the basis of use of the block of ultrasonic probes the optimum scheme of a sounding is offered and the analytical expression for calculation of required velocity considering varying of thickness of a covering is received.The method of acoustical measuring realized by a direct and reverse sounding of the objects with small aperture and angle probes was analysed and formulas for determination of speed of subsurface wave under protective layer of the wedge form have been got. An ultrasonic device is suggested for the excitationreception of subsurface waves with different speed in objects (on 20–35 %) using for the acoustic concordance of environments of metallic sound duct as a wedge. Possibility of leveling of interference in a protective layer to control efects in basis of material by a volume wave by creation of supporting echo-signal of longitudinal wave of the set frequency and entered normally to the surface of object was studied.

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Determination of anisotropic geometrical parameters for the electrical characterization of carbon/epoxy composite during oven curing

Composites Part A Applied Science and Manufacturing ◽

10.1016/j.compositesa.2015.10.022 ◽

2016 ◽

Vol 80 ◽

pp. 204-216 ◽

Cited By ~ 3

Author(s):

Sonia Sassi ◽

Philippe Marguerès ◽

Philippe Olivier ◽

Rébecca Le Begue

Keyword(s):

Epoxy Composite ◽

Electrical Characterization ◽

Geometrical Parameters

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Complete Williams Asymptotic Expansion near the Crack Tips of Collinear Cracks of Equal Lengths in an Infinite Plane

Solid State Phenomena ◽

10.4028/www.scientific.net/ssp.258.209 ◽

2016 ◽

Vol 258 ◽

pp. 209-212 ◽

Cited By ~ 2

Author(s):

Larisa Stepanova ◽

Pavel Roslyakov ◽

Tatjana Gerasimova

Keyword(s):

Plane Elasticity ◽

Analytical Determination ◽

Geometrical Parameters ◽

Infinite Plane ◽

Variable Theory ◽

Complex Variable Theory ◽

Plane Medium ◽

Crack Tips ◽

Plane Elasticity Theory

The present study is aimed at analytical determination of coefficients in crack tip expansion for two collinear finite cracks of equal lengths in an infinite plane medium. The study is based on the solutions of the complex variable theory in plane elasticity theory. The analytical dependence of the coefficients on the geometrical parameters and the applied loads for two finite cracks in an infinite plane medium is given. It is shown that the effect of the higher order terms of the Williams series expansion becomes more considerable at large distances from the crack tips. The knowledge of more terms of the stress asymptotic expansions allows us to approximate the stress field near the crack tips with high accuracy.

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Intellectual Measuring Complex for Control of Geometrical Parameters of Aviation Details

Handbook of Research on Artificial Intelligence Applications in the Aviation and Aerospace Industries - Advances in Mechatronics and Mechanical Engineering ◽

10.4018/978-1-7998-1415-3.ch015 ◽

2020 ◽

pp. 352-371

Author(s):

Mariia Kataieva ◽

Alina Yurchuk

Keyword(s):

Computer Simulation ◽

Measurement Error ◽

Three Dimensional ◽

Geometric Parameters ◽

Measurement Process ◽

Geometrical Parameters ◽

Automated Method ◽

Measuring Complex ◽

Graphic Depiction

This chapter proposes a new automated method of measuring complex three-dimensional surfaces of aircraft parts in static and dynamic modes. The method allows conducting measurements in closed conditions and at the site of the aircraft disposition. The method consists in the continuous determination of the coordinates of the points of the surface of the detail and their representation in a three-dimensional graphic depiction. New methods of measuring the geometric parameters of parts with the complex spatial surface are suggested. This opens the prospect for the development of new ways of measuring geometric parameters of parts in real-time with high metrological characteristics and computer simulation of the measurement process. The differential-digital method is based on the suggested zero-coordinate principle of the measurement process which involves simultaneous parts availability check, and connects measurement result obtained which provided a reduction in the order of measurement error.

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Determination of the Energy Capacity of Face Rock Breaking by the Geokhod’s Knife Operating Element and its Dependence on the External Propeller’s Pitch

E3S Web of Conferences ◽

10.1051/e3sconf/201910503024 ◽

2019 ◽

Vol 105 ◽

pp. 03024 ◽

Cited By ~ 2

Author(s):

Valery Nesterov ◽

Vladimir Aksenov ◽

Vladimir Sadovets ◽

Dmitry Pashkov ◽

Zhadyra Beysebayeva

Keyword(s):

Rock Breaking ◽

Geometrical Parameters ◽

Energy Capacity ◽

New Class ◽

Advantages And Disadvantages ◽

Operating Element ◽

Mining Conditions ◽

Breaking Energy ◽

Goals And Objectives

The article contains a method for determination of the energy capacity of face rock breaking by the knife operating element of the geokhod. In addition, the dependence of the breaking energy capacity on the pitch of the geokhod’s external propeller was revealed. The relevance of the study was considered. In order to set goals and objectives of the study, work features of new-class mining machines – geokhods and fundamental principles of geokhod technology were presented. Advantages and disadvantages of existing methods for determination of the energy capacity of rock breaking were identified, and the possibility of using them in calculation of power parameters of the geokhod’s knife operating element was assessed. Power and geometrical parameters of the geokhod’s knife operating element were determined, which affect the energy capacity of rock breaking. To determine the influence of the external propeller’s pitch on the breaking energy capacity, geometrical parameters of the knife operating element and parameters of mining conditions of workings were substantiated. As a result of the study, it was revealed that the energy capacity of rock breaking by the knife operating element decreases non-uniformly as the pitch of the external propeller increases.

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The DN − σ and Fundamental Plane Relations as Distance Indicators of Early Type Galaxies in the Virgo and Fornax Clusters

Symposium - International Astronomical Union ◽

10.1017/s0074180900232853 ◽

1996 ◽

Vol 171 ◽

pp. 366-366

Author(s):

M. D'Onofrio ◽

S. Zaggia ◽

M. Capaccioli ◽

G. Longo ◽

N. Caon

Keyword(s):

Rotation Velocity ◽

Geometrical Parameters ◽

Early Type ◽

Homogeneous Sample ◽

Fundamental Plane ◽

Total Luminosity ◽

The Mean ◽

Distance Indicators ◽

Light Profiles

We investigate the properties of early-type galaxies as distance indicators by applying the Dn – σ, Fundamental Plane (FP), and log(m) – log re relations to a complete and fairly homogeneous sample of galaxies members of the Virgo and Fornax clusters. The relative mean distance of the two clusters can be derived with an accuracy up to ∼ 3% provided that the internal kinematics of the galaxies is taken into account and a correct statistical approach is used.The residuals of the Dn – σ and FP relationships do not correlate with many structural and geometrical parameters of the galaxies: the mean effective surface brightness, the total luminosity, the average ellipticity and the Fourier coefficient a4 of the isophotes, and, the exponent m of the r1/m law which parametrizes the shape of the light profiles. On the other hand, the kinematics of the galaxies affect both relations producing residuals that correlate with the maximum rotation velocity Vmax and the (V/σ) ratio.Once confirmed by future more accurate observations, this effect would introduce a sistematic bias in the distance determination of the clusters; a problem difficult to manage if the internal kinematics of the cluster members is unknown.

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The influence of geometrical parameters of the forming channel on the boundary value of the axial force in the agglomeration process of dry ice

MATEC Web of Conferences ◽

10.1051/matecconf/201925405001 ◽

2019 ◽

Vol 254 ◽

pp. 05001 ◽

Cited By ~ 9

Author(s):

Jan Górecki ◽

Ireneusz Malujda ◽

Dominik Wilczyński

Keyword(s):

Carbon Dioxide ◽

Low Temperature ◽

Axial Force ◽

Environmental Conditions ◽

Main Parameter ◽

Geometrical Parameters ◽

Dry Ice ◽

Agglomeration Process ◽

Boundary Force

The article presents the results of study on the influence of geometrical parameters of the forming channels on axial force which is the main parameter of the agglomeration process of dry ice in the piston method. During research, the material was agglomerated utilizing different dies. The material is characterized by low temperature and sublimation under standard environmental conditions. The study focuses on determining the influence of geometrical parameters of the conical and cylindrical sections of the forming chamber which influence the value of yield stress in the carbon dioxide agglomeration process. The determination of the value of boundary force is the basis for formulating the construction assumptions which shall be the basis for designing and constructing the dry ice compaction and pelletization machine.

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Structure determination of two intercalated compounds VOPO4·(CH2)4O and VOPO4·OH—(CH2)2—O—(CH2)2—OH; synchrotron powder diffraction and molecular modelling

Acta Crystallographica Section B Structural Science ◽

10.1107/s0108768100015603 ◽

2001 ◽

Vol 57 (2) ◽

pp. 178-183 ◽

Cited By ~ 24

Author(s):

Kees Goubitz ◽

Pavla Čapková ◽

Klára Melánová ◽

Wim Molleman ◽

Henk Schenk

Keyword(s):

Powder Diffraction ◽

Structure Determination ◽

Crystal Packing ◽

Geometrical Parameters ◽

Vanadyl Phosphate ◽

Guest Molecules ◽

Intercalated Compounds ◽

Synchrotron Powder Diffraction ◽

Layer Stacking

The crystal structures of two intercalated compounds have been determined using a combination of synchrotron powder diffraction and molecular mechanics simulations: (1) vanadyl phosphate intercalated with tetrahydrofuran, VOPO4·(CH2)4O, and (2) vanadyl phosphate intercalated with diethylene glycol, VOPO4·HO(CH2)2O(CH2)2OH. Both intercalates preserve the tetragonal space group P4/n, as found in the host structure VOPO4·2H2O. (1): a = 6.208, c = 8.930 Å, Z = 2, Dx = 2.51 g cm−3; (2): a = 6.223, c = 11.417 Å, Z = 2, Dx = 2.66 g cm−3. Both intercalates exhibit the same type of orientational disorder in the arrangement of guest molecules, as observed in the same host compound intercalated with water. These two intercalates also exhibit, rather surprisingly, perfect ordering in layer stacking without the displacement disorder, characteristic of many intercalated layered structures. Thanks to this regularity in the arrangement of guests and layers, synchrotron powder diffraction could be used in the present structure determination. The present results also enabled the analysis of the effect of geometrical parameters characterizing the mutual host–guest complementarity and the effect of host–guest and guest–guest interaction on the crystal packing of intercalates.

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Finite Element Analysis of PMMA Stretch Blow Molding

International Journal of Manufacturing Engineering ◽

10.1155/2014/175743 ◽

2014 ◽

Vol 2014 ◽

pp. 1-6

Author(s):

Afef Bougharriou ◽

Mohieddine Jeridi ◽

Mohamed Hdiji ◽

Anoir Boughrira ◽

Kacem Saï

Keyword(s):

Finite Element ◽

Thickness Distribution ◽

Geometrical Parameters ◽

Molding Process ◽

Element Analysis ◽

Blow Molding ◽

Stretch Blow Molding ◽

Crucial Parameter

The electric bubbles are a useful product made of PMMA material. They are produced by the stretch blow molding process. Thickness, which reflects the quality of the electric bubble, is a crucial parameter that deserves special attention for the molding process. In this work, finite element simulations of the stretch blow molding process are performed aiming at the determination of the preform geometry to ensure homogeneous thickness of the finished product. The geometrical parameters of the preform are optimized allowing a better homogeneity thickness compared to existing data. The predicted parameters allow the improvement of the thickness distribution. The standard deviation of the thickness is reduced to about 95% compared to the existing bubble.

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