Publisher's Note: Short-circuit boundary conditions in ferroelectricPbTiO3thin films [Phys. Rev. B74, 054112 (2006)]

Abstract The shear surface wave at the free traction surface of half- infinite functionally graded magneto-electro-elastic material with initial stress is investigated. The material parameters are assumed to vary ex- ponentially along the thickness direction, only. The velocity equations of shear surface wave are derived on the electrically or magnetically open circuit and short circuit boundary conditions, based on the equations of motion of the graded magneto-electro-elastic material with the initial stresses and the free traction boundary conditions. The dispersive curves are obtained numerically and the influences of the initial stresses and the material gradient index on the dispersive curves are discussed. The investigation provides a basis for the development of new functionally graded magneto-electro-elastic surface wave devices.

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Thermal Conductivities of PZT Piezoelectric Ceramics under Different Electrical Boundary Conditions

Insight - Material Science ◽

10.18282/ims.v3i1.301 ◽

2020 ◽

Vol 3 (1) ◽

pp. 10

Author(s):

Husain N. Shekhan ◽

Erkan A. Gurdal ◽

Lalitha Ganapatibhotla ◽

Janna K. Maranas ◽

Ron Staut ◽

...

Keyword(s):

Thermal Conductivity ◽

Thermal Properties ◽

Boundary Conditions ◽

Lead Zirconate Titanate ◽

Electromechanical Coupling ◽

Short Circuit ◽

Coupling Factor ◽

Open Circuit ◽

Electrical Boundary Conditions ◽

Poling Direction

Physical properties of polycrystalline lead-zirconate-titanate (PZT) changes according to electrical boundary conditions and poling. This paper reports the thermal properties of poled and unpoled PZT's in the poling direction for open circuit and short circuit conditions. The authors found that the short-circuit condition exhibited the largest thermal conductivity than the open-circuit condition. In the relationship between these two thermal properties, the authors propose the "electrothermal" coupling factor kκ33, which is similar to the electromechanical coupling factor k33 relating the elastic compliances under short- and open-circuit conditions. On the other hand, the thermal conductivity of the unpoled specimen exhibits the lowest thermal conductivity, in comparison with the poled specimens, which suggests the importance of phonon mode scattering on the thermal conductivity with respect to elastic compliance.

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A Structural Based Thermal Model Description for Vertical SiC Power MOSFETs under Fault Conditions

Active and Passive Electronic Components ◽

10.1155/2016/9414901 ◽

2016 ◽

Vol 2016 ◽

pp. 1-12 ◽

Cited By ~ 3

Author(s):

Andreas Maerz ◽

Teresa Bertelshofer ◽

Mark-M. Bakran

Keyword(s):

Boundary Conditions ◽

Thermal Model ◽

Short Circuit ◽

Gate Oxide ◽

Power Converter ◽

Junction Temperature ◽

Voltage Source ◽

Model Description ◽

General Description ◽

Testing Procedures

The accurate prediction of the SiC MOSFET withstanding time for single fault events greatly influences the requirements for device protection circuits for these devices in power converter applications, like voltage source inverters or power electronic transformers. For this reason, a thermal model, based on the structural design and the physical dimensions of the chip as well as material properties of 4H-SiC, is proposed. This article gives a general description of the thermal behaviour of vertical SiC MOSFET under various driving and boundary conditions in case of a short-circuit event. The thermal model substitutes destructive tests of a device for an individual set of boundary conditions of an occurring fault event. The validity of the analytically parametrised thermal model is verified by experimental short-circuit tests of state-of-the-art vertical SiC MOSFETs for a set of various boundary conditions. The investigated thermal model can furthermore be used to standardise different gate-oxide degradation values from the literature for means of lifetime prediction of the gate oxide for an individual application under repetitive occurring fault or overload conditions. These manufacturer specific reported values measured with no standardised testing procedures can be translated into a maximum junction temperature, which is repeatedly reached. The thermal model therefore provides a unifying parameter for the gate-oxide lifetime calculation for an individual chip and application.

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Short-circuit boundary conditions in ferroelectricPbTiO3thin films

Physical Review B ◽

10.1103/physrevb.74.054112 ◽

2006 ◽

Vol 74 (5) ◽

Cited By ~ 25

Author(s):

Alexie M. Kolpak ◽

Na Sai ◽

Andrew M. Rappe

Keyword(s):

Boundary Conditions ◽

Short Circuit

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A method for choosing the optimal quantity of short-circuit indicating devices to enhance power supply reliability

E3S Web of Conferences ◽

10.1051/e3sconf/201912402007 ◽

2019 ◽

Vol 124 ◽

pp. 02007

Author(s):

D. Köppen ◽

O. V. Vladimirov ◽

T. A. Musaev ◽

O. V. Fedorov

Keyword(s):

Mathematical Model ◽

Boundary Conditions ◽

Power Supply ◽

Short Circuit ◽

Power Grid ◽

Problem Solution ◽

Optimization Task ◽

Optimal Quantity ◽

Supply Reliability

This article considers a method for solving the problem of choosing the optimal quantity of short-circuit indicating devices for providing a required reliability of the 6(10) kV distribution power grid. Compatibility of the equipment powered was taken into account. An outcome of the problem solution became a mathematical model; an optimization task, limiting and boundary conditions were formulated.

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Propagation of Surface Waves in a Homogeneous Layer of Finite Thickness over an Initially Stressed Functionally Graded Magnetic-Electric-Elastic Half-Space

Journal of Theoretical and Applied Mechanics ◽

10.1515/jtam-2015-0005 ◽

2015 ◽

Vol 45 (1) ◽

pp. 69-86 ◽

Cited By ~ 4

Author(s):

Li Li ◽

P. J. Wei

Keyword(s):

Boundary Conditions ◽

Half Space ◽

Love Wave ◽

Short Circuit ◽

Finite Thickness ◽

Elastic Half Space ◽

Open Circuit ◽

Functionally Graded ◽

Initial Stresses ◽

Homogeneous Layer

Abstract The propagation behaviour of Love wave in an initially stressed functionally graded magnetic-electric-elastic half-space carrying a homogeneous layer is investigated. The material parameters in the substrate are assumed to vary exponentially along the thickness direction only. The velocity equations of Love wave are derived on the electrically or magnetically open circuit and short circuit boundary conditions, based on the equations of motion of the graded magnetic-electric-elastic mate- rial with the initial stresses and the free traction boundary conditions of surface and the continuous boundary conditions of interface. The dispersive curves are obtained numerically and the influences of the initial stresses and the material gradient index on the dispersive curves are dis- cussed. The investigation provides a basis for the development of new functionally graded magneto-electro-elastic surface wave devices.

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Structural Imperfections in thin Oxide Films Formed on Some Fe- and Ni-Base Alloys

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100069545 ◽

1970 ◽

Vol 28 ◽

pp. 510-511

Author(s):

L. P. Lemaire ◽

D. E. Fornwalt ◽

F. S. Pettit ◽

B. H. Kear

Keyword(s):

Oxide Scale ◽

Oxidation Process ◽

Short Circuit ◽

Protective Oxide ◽

Protective Oxide Scale ◽

Thin Oxide Films ◽

Diffusion Paths ◽

Oxidation Resistant ◽

Structural Imperfections ◽

Short Circuit Diffusion

Oxidation resistant alloys depend on the formation of a continuous layer of protective oxide scale during the oxidation process. The initial stages of oxidation of multi-component alloys can be quite complex, since numerous metal oxides can be formed. For oxidation resistance, the composition is adjusted so that selective oxidation occurs of that element whose oxide affords the most protection. Ideally, the protective oxide scale should be i) structurally perfect, so as to avoid short-circuit diffusion paths, and ii) strongly adherent to the alloy substrate, which minimizes spalling in response to thermal cycling. Small concentrations (∼ 0.1%) of certain reactive elements, such as yttrium, markedly improve the adherence of oxide scales in many alloy systems.

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Use of the Magnetostatic Analogue In Electromagnetic Lens Engineering

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100068795 ◽

1970 ◽

Vol 28 ◽

pp. 360-361

Author(s):

John W. Coleman

Keyword(s):

Boundary Conditions ◽

High Performance ◽

Force Fields ◽

Optical Design ◽

Direct Conversion ◽

Design Engineering ◽

Design Data ◽

Scalar Potentials ◽

Geometric Elements ◽

At Will

In the design engineering of high performance electromagnetic lenses, the direct conversion of electron optical design data into drawings for reliable hardware is oftentimes difficult, especially in terms of how to mount parts to each other, how to tolerance dimensions, and how to specify finishes. An answer to this is in the use of magnetostatic analytics, corresponding to boundary conditions for the optical design. With such models, the magnetostatic force on a test pole along the axis may be examined, and in this way one may obtain priority listings for holding dimensions, relieving stresses, etc..The development of magnetostatic models most easily proceeds from the derivation of scalar potentials of separate geometric elements. These potentials can then be conbined at will because of the superposition characteristic of conservative force fields.

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