Improved Wheeler Cap Method Based on an Equivalent High-Order Circuit Model

The paper presents a circuit model for the computationally efficient design of a planar Short-Circuited Self-Excited EBG Resonator Antenna (SC SE-EBG-RA). To this purpose, the same circuit model previously presented for the Open-Circuited version of the antenna is modified to be applicable to the SC version. Detailed HFSS modeling and simulation corroborate the accuracy of the model in predicting the antenna resonance. The efficiency of the designed antenna is calculated by a simulated Wheeler Cap Method (WCM) and is compared with the standard efficiency given by the numerical analyzer. The EM modeling is arranged so as to incorporate the effects of the SMA connector, discontinuities, and the WC, emulating a real WC measurement and yielding a high degree of confidence in the results. Overall, a small antenna sized0.34λ×0.30λ×0.03λwith 93% verified efficiency is achieved, which is also compiled with affordable manufacturing processes.

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High order distribute circuit model of laminated busbars and its order reduction techniques for simulating fast turn-on and turn-off transients

International Journal of Applied Electromagnetics and Mechanics ◽

10.3233/jae-209354 ◽

2020 ◽

Vol 64 (1-4) ◽

pp. 473-482

Author(s):

Ning Wang ◽

Huifang Wang ◽

Shiyou Yang

Keyword(s):

Electronic Device ◽

Order Reduction ◽

Circuit Model ◽

High Order ◽

Second Phase ◽

Frequency Model ◽

Turn On ◽

Reduction Techniques ◽

Proposed Model ◽

Two Phases

A high order distribute circuit model of a laminated busbar is proposed in order to accurately simulate the fast turn-on and turn-off transients of a modern power electronic device. In the model, the predominant stray parameters of the loop inductance and the stray capacitance are considered. Moreover, a model order reduction (MOR) technique using the zero-pole elimination technique is presented to combat the high complexity of the extremely computationally expensive circuit model. The MOR methodology is implemented in two phases. The first phase is to compute the reduced order frequency model. In the second phase, this reduced model is synthesized into a circuit model in a netlist representation (RLC elements), which can be integrated in any SPICE-like circuit solver. Finally, the proposed model and methodology are used to solve the transient performances of a prototype IGBT based inverter, showing excellent agreements with the experimental results.

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Decision letter for "A crabs’ high‐order brain center resolved as a mushroom body‐like structure"

10.1002/cne.24960/v2/decision1 ◽

2020 ◽

Keyword(s):

Mushroom Body ◽

High Order ◽

Brain Center

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Review for "A crabs’ high‐order brain center resolved as a mushroom body‐like structure"

10.1002/cne.24960/v1/review1 ◽

2020 ◽

Keyword(s):

Mushroom Body ◽

High Order ◽

Brain Center

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Determination of the Burgers vector of a dislocation in a Fe-Mn alloy by weak-beam image in HVEM

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100108799 ◽

1978 ◽

Vol 36 (1) ◽

pp. 330-331

Author(s):

Y. Ishida ◽

H. Ishida ◽

K. Kohra ◽

H. Ichinose

Keyword(s):

High Order ◽

Simulation Technique ◽

The Other ◽

Image Simulation ◽

Diffraction Vector ◽

Burgers Vector ◽

Weak Beam ◽

Beam Image ◽

Edge Component

IntroductionA simple and accurate technique to determine the Burgers vector of a dislocation has become feasible with the advent of HVEM. The conventional image vanishing technique(1) using Bragg conditions with the diffraction vector perpendicular to the Burgers vector suffers from various drawbacks; The dislocation image appears even when the g.b = 0 criterion is satisfied, if the edge component of the dislocation is large. On the other hand, the image disappears for certain high order diffractions even when g.b ≠ 0. Furthermore, the determination of the magnitude of the Burgers vector is not easy with the criterion. Recent image simulation technique is free from the ambiguities but require too many parameters for the computation. The weak-beam “fringe counting” technique investigated in the present study is immune from the problems. Even the magnitude of the Burgers vector is determined from the number of the terminating thickness fringes at the exit of the dislocation in wedge shaped foil surfaces.

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The usefulness of high index low symmetry zone axes for holz line analysis

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100126718 ◽

1987 ◽

Vol 45 ◽

pp. 384-385

Author(s):

C. M. Sung ◽

D. B. Williams

Keyword(s):

Lattice Parameter ◽

High Order ◽

Zone Axis ◽

High Index ◽

High Symmetry ◽

Second Phases ◽

Line Patterns ◽

Low Symmetry ◽

Line Analysis

Researchers have tended to use high symmetry zone axes (e.g. <111> <114>) for High Order Laue Zone (HOLZ) line analysis since Jones et al reported the origin of HOLZ lines and described some of their applications. But it is not always easy to find HOLZ lines from a specific high symmetry zone axis during microscope operation, especially from second phases on a scale of tens of nanometers. Therefore it would be very convenient if we can use HOLZ lines from low symmetry zone axes and simulate these patterns in order to measure lattice parameter changes through HOLZ line shifts. HOLZ patterns of high index low symmetry zone axes are shown in Fig. 1, which were obtained from pure Al at -186°C using a double tilt cooling holder. Their corresponding simulated HOLZ line patterns are shown along with ten other low symmetry orientations in Fig. 2. The simulations were based upon kinematical diffraction conditions.

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Are HOLZ lines kinematic in off-zone-axis orientation?

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100149295 ◽

1993 ◽

Vol 51 ◽

pp. 692-693

Author(s):

J. M. Zuo ◽

A. L. Weickenmeier ◽

R. Holmestad ◽

J. C. H. Spence

Keyword(s):

Structure Determination ◽

Standard Procedure ◽

High Order ◽

Zone Axis ◽

Great Promise ◽

Line Position ◽

Measured Intensity ◽

Constant Intensity ◽

Axis Orientation ◽

Diffraction Condition

The application of high order reflections in a weak diffraction condition off the zone axis center, including those in high order laue zones (HOLZ), holds great promise for structure determination using convergent beam electron diffraction (CBED). It is believed that in this case the intensities of high order reflections are kinematic or two-beam like. Hence, the measured intensity can be related to the structure factor amplitude. Then the standard procedure of structure determination in crystallography may be used for solving unknown structures. The dynamic effect on HOLZ line position and intensity in a strongly diffracting zone axis is well known. In a weak diffraction condition, the HOLZ line position may be approximated by the kinematic position, however, it is not clear whether this is also true for HOLZ intensities. The HOLZ lines, as they appear in CBED patterns, do show strong intensity variations along the line especially near the crossing of two lines, rather than constant intensity along the Bragg condition as predicted by kinematic or two beam theory.

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