Hybrid analytical models to estimate non-equilibrium temperatures in live-tissues based on appropriate initial thermal-field and non-invasive therapeutic heating

Abstract Melt pool modeling is critical for model-based uncertainty quantification (UQ) and quality control in metallic Additive Manufacturing (AM). Finite element (FE) simulation for thermal modeling in metal AM, however, is tedious and time-consuming. This paper presents a multi-fidelity point-cloud neural network method (MF-PointNN) for surrogate modeling of melt pool based on FE simulation data. It merges the feature representations of low-fidelity (LF) analytical model and high-fidelity (HF) FE simulation data through the theory of transfer learning (TL). A basic PointNN is firstly trained using LF data to construct correlation between the inputs and thermal field of analytical models. Then, the basic PointNN is updated and fine-tuned using the small size of HF data to build the MF-PointNN. The trained MF-PointNN allows for efficient mapping from input variables and spatial positions to thermal histories, and thereby efficiently predict the three-dimensional melt pool. Results of melt pool modeling of electron beam additive manufacturing (EBAM) of Ti-6Al-4V under uncertainty demonstrate the efficacy of the proposed approach.

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Analytical models of high velocity non-equilibrium of polyatomic gas mixtures

10.1063/1.5034672 ◽

2018 ◽

Author(s):

M. M. Kuznetsov ◽

Yu. D. Kuleshova ◽

Yu. G. Reshetnikova ◽

L. V. Smotrova

Keyword(s):

High Velocity ◽

Gas Mixtures ◽

Analytical Models ◽

Polyatomic Gas ◽

Polyatomic Gas Mixtures ◽

Non Equilibrium

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Non-invasive estimation of dissipation from non-equilibrium fluctuations in chemical reactions

The Journal of Chemical Physics ◽

10.1063/1.4821760 ◽

2013 ◽

Vol 139 (12) ◽

pp. 124109 ◽

Cited By ~ 8

Author(s):

S. Muy ◽

A. Kundu ◽

D. Lacoste

Keyword(s):

Chemical Reactions ◽

Equilibrium Fluctuations ◽

Non Invasive ◽

Non Equilibrium

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Perturbative non-equilibrium thermal field theory to all orders in gradient expansion

Physics Letters B ◽

10.1016/j.physletb.2013.05.044 ◽

2013 ◽

Vol 724 (1-3) ◽

pp. 56-62 ◽

Cited By ~ 12

Author(s):

Peter Millington ◽

Apostolos Pilaftsis

Keyword(s):

Field Theory ◽

Thermal Field Theory ◽

Thermal Field ◽

Gradient Expansion ◽

Non Equilibrium

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Termovision and electricity capacitance measurements as a evaluation of a helicopter rotor’s blades delamination

Journal of Konbin ◽

10.1515/jok-2015-0067 ◽

2015 ◽

Vol 36 (1) ◽

pp. 187-200

Author(s):

Andrzej Gębura ◽

Michał Poradowski

Keyword(s):

Composite Structures ◽

Thermal Field ◽

Electric Heating ◽

Essential Elements ◽

Rotor Blades ◽

Heat Element ◽

Capacitance Measurements ◽

Non Invasive ◽

Electric Heating Element ◽

Potential Area

Abstract The article presents essential elements reached during investigations of heat section of rotor blades which have been done in AFIT. The investigations were related to a valuation of helicopter’s rotor blades delamination. They used a method of thermal field measurement as well as a electricity capacitance between an airframe and a heat element of the installation. A suggestion of such measurements appeared during the disassembly of rotor blade heat sections when some local unglue of heat element’s tape from the structure of blade’s heating pack has seen. Spots nearby separation of adhesive are a potential area of a local temperature increase, both the electric heating element and the mechanical structure of the blade. This is especially dangerous for composite structures. Overheated composite structures characterized by reduced flexibility and becomes prone to cracking. Therefore, the possibility of non-invasive monitoring adhesive spots, without removing the blades would be particularly useful.

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X-ray microtomography

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100107058 ◽

1988 ◽

Vol 46 ◽

pp. 998-999

Author(s):

H.W. Deckman ◽

B.F. Flannery ◽

J.H. Dunsmuir ◽

K.D' Amico

Keyword(s):

Computed Tomography ◽

Internal Structure ◽

Imaging Technique ◽

Three Dimensional ◽

Tissue Structure ◽

Individual Element ◽

X Ray ◽

Non Invasive ◽

Panoramic Imaging ◽

Three Dimensional Images

We have developed a new X-ray microscope which produces complete three dimensional images of samples. The microscope operates by performing X-ray tomography with unprecedented resolution. Tomography is a non-invasive imaging technique that creates maps of the internal structure of samples from measurement of the attenuation of penetrating radiation. As conventionally practiced in medical Computed Tomography (CT), radiologists produce maps of bone and tissue structure in several planar sections that reveal features with 1mm resolution and 1% contrast. Microtomography extends the capability of CT in several ways. First, the resolution which approaches one micron, is one thousand times higher than that of the medical CT. Second, our approach acquires and analyses the data in a panoramic imaging format that directly produces three-dimensional maps in a series of contiguous stacked planes. Typical maps available today consist of three hundred planar sections each containing 512x512 pixels. Finally, and perhaps of most import scientifically, microtomography using a synchrotron X-ray source, allows us to generate maps of individual element.

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Application of analytical electron microscopy to studies of equilibrium and non-equilibrium segregation in materials

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100130705 ◽

1992 ◽

Vol 50 (2) ◽

pp. 1214-1215

Author(s):

Edward A Kenik

Keyword(s):

Electron Microscopy ◽

Analytical Electron Microscopy ◽

Extended Defects ◽

Probe Diameter ◽

Specimen Holder ◽

Analytical Electron ◽

Scanning Transmission ◽

Solute Atoms ◽

Equilibrium Segregation ◽

Non Equilibrium

Segregation of solute atoms to grain boundaries, dislocations, and other extended defects can occur under thermal equilibrium or non-equilibrium conditions, such as quenching, irradiation, or precipitation. Generally, equilibrium segregation is narrow (near monolayer coverage at planar defects), whereas non-equilibrium segregation exhibits profiles of larger spatial extent, associated with diffusion of point defects or solute atoms. Analytical electron microscopy provides tools both to measure the segregation and to characterize the defect at which the segregation occurs. This is especially true of instruments that can achieve fine (<2 nm width), high current probes and as such, provide high spatial resolution analysis and characterization capability. Analysis was performed in a Philips EM400T/FEG operated in the scanning transmission mode with a probe diameter of <2 nm (FWTM). The instrument is equipped with EDAX 9100/70 energy dispersive X-ray spectrometry (EDXS) and Gatan 666 parallel detection electron energy loss spectrometry (PEELS) systems. A double-tilt, liquid-nitrogen-cooled specimen holder was employed for microanalysis in order to minimize contamination under the focussed spot.

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