scholarly journals On Differential Imaging Using Electromagnetic Simulation for Vehicular Antenna Signature Analysis

Sensors ◽  
2021 ◽  
Vol 21 (11) ◽  
pp. 3796
Author(s):  
Jose Antonio Solano-Perez ◽  
María-Teresa Martínez-Inglés ◽  
Jose-Maria Molina-Garcia-Pardo ◽  
Jordi Romeu ◽  
Lluis Jofre-Roca ◽  
...  
Keyword(s):  
Current Trend ◽  
Surface Current ◽  
Simulation Software ◽  
Electromagnetic Simulation ◽  
The Novel ◽  
Full Wave ◽  
Vehicle Structure ◽  
Novel Concept ◽  
Differential Imaging ◽  
Vehicle Platform

The current trend in vehicles is to integrate a wide number of antennae and sensors operating at a variety of frequencies for sensing and communications. The integration of these antennae and sensors in the vehicle platform is complex because of the way in which the antenna radiation patterns interact with the vehicle structure and other antennae/sensors. Consequently, there is a need to study the radiation pattern of each antenna or, alternatively, the currents induced on the surface of the vehicle to optimize the integration of multiple antennae. The novel concept of differential imaging represents one method by which it is possible to obtain the surface current distribution without introducing any perturbing probe. The aim of this study was to develop and confirm the assumptions that underpin differential imaging by means of full-wave electromagnetic simulation, thereby providing additional verification of the concept. The simulation environment and parameters were selected to replicate the conditions in which real measurements were taken in previous studies. The simulations were performed using Ansys HFSS simulation software. The results confirm that the approximations are valid, and the differential currents are representative of the induced surface currents generated by a monopole positioned on the top of a vehicle.

scholarly journals Resonant Frequency Modeling of Microwave Antennas Using Gaussian Process Based on Semisupervised Learning

Complexity ◽  
2020 ◽  
Vol 2020 ◽  
pp. 1-12 ◽  
Author(s):  
Jing Gao ◽  
Yubo Tian ◽  
Xie Zheng ◽  
Xuezhi Chen
Keyword(s):  
Resonant Frequency ◽  
Gaussian Process ◽  
Microstrip Antennas ◽  
Semisupervised Learning ◽  
Simulation Software ◽  
Electromagnetic Simulation ◽  
Initial Training ◽  
Full Wave ◽  
Training Samples ◽  
Gp Model

For the optimal design of electromagnetic devices, it is the most time consuming to obtain the training samples from full wave electromagnetic simulation software, including HFSS, CST, and IE3D. Traditional machine learning methods usually use only labeled samples or unlabeled samples, but in practical problems, labeled samples and unlabeled samples coexist, and the acquisition cost of labeled samples is relatively high. This paper proposes a semisupervised learning Gaussian Process (GP), which combines unlabeled samples to improve the accuracy of the GP model and reduce the number of labeled training samples required. The proposed GP model consists two parts: initial training and self-training. In the process of initial training, a small number of labeled samples obtained by full wave electromagnetic simulation are used for training the initial GP model. Afterwards, the trained GP model is copied to another GP model in the process of self-training, and then the two GP models will update after crosstraining with different unlabeled samples. Using the same test samples for testing and updating, a model with a smaller error will replace another. Repeat the self-training process until a predefined stopping criterion is met. Four different benchmark functions and resonant frequency modeling problems of three different microstrip antennas are used to evaluate the effectiveness of the GP model. The results show that the proposed GP model has a good fitting effectiveness on benchmark functions. For microstrip antennas resonant frequency modeling problems, in the case of using the same labeled samples, its predictive ability is better than that of the traditional supervised GP model.

scholarly journals Racism and Antiracism in the Liberal International Order

2020 ◽  
pp. 1-24
Author(s):  
Zoltán I. Búzás
Keyword(s):  
International Relations ◽  
Racial Inequality ◽  
Racial Diversity ◽  
International Order ◽  
Interdisciplinary Studies ◽  
Racial Equality ◽  
The Novel ◽  
Current Regime ◽  
Novel Concept ◽  
Comprehensive Framework

Abstract Formal racial equality is a key aspect of the current Liberal International Order (LIO). It is subject to two main challenges: resurgent racial nationalism and substantive racial inequality. Combining work in International Relations with interdisciplinary studies on race, I submit that these challenges are the latest iteration of struggles between two transnational coalitions over the LIO's central racial provisions, which I call racial diversity regimes (RDRs). The traditional coalition has historically favored RDRs based on racial inequality and racial nationalism. The transformative coalition has favored RDRs based on racial equality and nonracial nationalism. I illustrate the argument by tracing the development of the liberal order's RDR as a function of intercoalitional struggles from one based on racial nationalism and inequality in 1919 to the current regime based on nonracial nationalism and limited equality. Today, racial nationalists belong to the traditional coalition and critics of racial inequality are part of the transformative coalition. The stakes of their struggles are high because they will determine whether we will live in a more racist or a more antiracist world. This article articulates a comprehensive framework that places race at the heart of the liberal order, offers the novel concept of “embedded racism” to capture how sovereignty shields domestic racism from foreign interference, and proposes an agenda for mainstream International Relations that takes race seriously.

scholarly journals Using green infrastructure to stimulate discourse with and for planning practice: experiences with fuzzy concepts from a pan-European, a national and a local perspective

2021 ◽  
Author(s):  
Rieke Hansen ◽  
Martina van Lierop ◽  
Werner Rolf ◽  
Damjana Gantar ◽  
Ina Šuklje Erjavec ◽  
...  
Keyword(s):  
Green Infrastructure ◽  
Regional Cooperation ◽  
Knowledge Exchange ◽  
Stakeholder Involvement ◽  
The Novel ◽  
Planning Practice ◽  
Regional Project ◽  
Development Processes ◽  
Guidance Documents ◽  
Novel Concept

AbstractConcepts such as green infrastructure, nature-based solutions, and ecosystem services gained popularity in recent discourses on urban planning. Despite their recognition as innovative concepts, all of them share a degree of ambiguity. Fuzziness can be a weakness but also an opportunity to shape novel concepts together with the stakeholders that are supposed to implement them in the planning practice. The paper traces concept development processes of green infrastructure through transdisciplinary knowledge exchange in three different projects, a European and a national research project and a local city-regional project as part of an EU regional cooperation project. In all projects, the green infrastructure concept evolved in different stages. Stakeholder involvement during these stages span from consultation to co-creation. The cases reveal two different approaches: concepts that are developed “for planning practice” might be based on a plethora of insight via consultation, while those “with planning practice” foster co-creation and might result in high acceptance among the involved stakeholders. Depending on the purpose of the novel concept, each approach can be beneficial and result in practice-related and operational products, such as guidance documents or planning strategies. However, the cases also show that in any new context an exchange about fuzzy concepts is not only needed but also a chance to stimulate cooperation and joint understanding about urban challenges and how to address them.

scholarly journals CD5 costimulation induces stable Th17 development by promoting IL-23R expression and sustained STAT3 activation

Blood ◽  
2011 ◽  
Vol 118 (23) ◽  
pp. 6107-6114 ◽  
Author(s):  
Jelle de Wit ◽  
Yuri Souwer ◽  
Astrid J. van Beelen ◽  
Rosa de Groot ◽  
Femke J. M. Muller ◽  
...  
Keyword(s):  
Th17 Cells ◽  
Transforming Growth Factor ◽  
Transforming Growth Factor Β ◽  
Orphan Receptor ◽  
The Novel ◽  
Cd28 Costimulation ◽  
Th17 Differentiation ◽  
Novel Concept ◽  
Transcription 3 ◽  
Lymphocyte Receptors

Abstract IL-17–producing CD4+ T helper (Th17) cells are important for immunity against extracellular pathogens and in autoimmune diseases. The factors that drive Th17 development in human remain a matter of debate. Here we show that, compared with classic CD28 costimulation, alternative costimulation via the CD5 or CD6 lymphocyte receptors forms a superior pathway for human Th17-priming. In the presence of the Th17-promoting cytokines IL-1β, IL-6, IL-23, and transforming growth factor-β (TGF-β), CD5 costimulation induces more Th17 cells that produce higher amounts of IL-17, which is preceded by prolonged activation of signal transducer and activator of transcription 3 (STAT3), a key regulator in Th17 differentiation, and enhanced levels of the IL-17–associated transcription factor retinoid-related orphan receptor-γt (ROR-γt). Strikingly, these Th17-promoting signals critically depend on CD5-induced elevation of IL-23 receptor (IL-23R) expression. The present data favor the novel concept that alternative costimulation via CD5, rather than classic costimulation via CD28, primes naive T cells for stable Th17 development through promoting the expression of IL-23R.

scholarly journals Phylogenetic Core Groups: a promising concept in search of a consistent methodological framework

Microbiome ◽  
2021 ◽  
Vol 9 (1) ◽  
Author(s):  
Alberto Pascual-García
Keyword(s):  
Microbial Communities ◽  
Microbial Ecology ◽  
Environmental Conditions ◽  
The Novel ◽  
Methodological Framework ◽  
Operational Taxonomic Units ◽  
Traditional Classification ◽  
Taxonomical Classification ◽  
Novel Concept

AbstractIn this comment, we analyse the conceptual framework proposed by Aguirre de Cárcer (Microbiome 7:142, 2019), introducing the novel concept of Phylogenetic Core Groups (PCGs). This notion aims to complement the traditional classification in operational taxonomic units (OTUs), widely used in microbial ecology, to provide a more intrinsic taxonomical classification which avoids the use of pre-determined thresholds. However, to introduce this concept, the author frames his proposal in a wider theoretical framework based on a conceptualization of selection that we argue is a tautology. This blurs the subsequent formulation of an assembly principle for microbial communities, favouring that some contradictory examples introduced to support the framework appear aligned in their conclusions. And more importantly, under this framework and its derived methodology, it is not possible to infer PCGs from data in a consistent way. We reanalyse the proposal to identify its logical and methodological flaws and, through the analysis of synthetic scenarios, we propose a number of methodological refinements to contribute towards the determination of PCGs in a consistent way. We hope our analysis will promote the exploration of PCGs as a potentially valuable tool, helping to bridge the gap between environmental conditions and community composition in microbial ecology.

Performance Benefits of R718 Turbo-Compression Cycle Using 3-Port Condensing Wave Rotors

2004 ◽  
Author(s):  
Amir A. Kharazi ◽  
Pezhman Akbari ◽  
Norbert Mu¨ller
Keyword(s):  
Performance Enhancement ◽  
The Novel ◽  
Wave Rotor ◽  
Flash Evaporation ◽  
Pressurized Water ◽  
Wave Rotors ◽  
Compression Cycle ◽  
Performance Map ◽  
Wave Compression ◽  
Novel Concept

A number of technical challenges have often hindered the economical application of refrigeration cycles using water (R718) as refrigerant. The novel concept of condensing wave rotor provides a solution for performance improvement of R718 refrigeration cycles. The wave rotor implementation can increase efficiency and reduce the size and cost of R718 units. The condensing wave rotor employs pressurized water to pressurize, desuperheat, and condense the refrigerant vapor — all in one dynamic process. In this study, the underlying phenomena of flash evaporation, shock wave compression, desuperheating, and condensation inside the wave rotor channels are described in a wave and phase-change diagram. A computer program based on a thermodynamic model is generated to evaluate the performance of R718 baseline and wave-rotor-enhanced cycles. The detailed thermodynamic approach for the baseline and the modified cycles is described. The effect of some key parameters on the performance enhancement is demonstrated as an aid for optimization. A generated performance map summarizes the findings.

3D Modelling Of The Novel Nanoscale Screen-Grid FET

2006 ◽  
Vol 913 ◽  
Author(s):  
Pei W. Ding ◽  
Kristel Fobelets ◽  
Jesus E Velazquez-Perez
Keyword(s):  
Field Effect ◽  
Field Effect Transistor ◽  
Simulation Software ◽  
The Novel ◽  
Channel Coupling ◽  
3 Dimensional ◽  
Gate Control ◽  
Effect Transistor ◽  
Screen Grid ◽  
Output Characteristics

AbstractA novel field effect transistor (FET) that uses 3-dimensional (3-D) embedded gate fingers – the Screen-Grid Field Effect Transistor (SGFET) – is proposed. The gating action of the SGFET is based on the design of multiple gating cylinders into the channel region, perpendicular to the current flow. Such configuration allows a full 3-D gate control of the current which improves the device characteristics by increasing the gate to channel coupling. Initial investigations of the SGFET using 3-D TCAD TaurusTM simulation software are presented in this paper. The results indicate that the proposed SGFET offers the possibility of downscaling without degrading the output characteristics. A comparison between the SGFET and both bulk and SOI MOSFETs shows the superior characteristics of the SGFET for low power operation.

Unconditionally Stable MFLTD Method for the Full Wave Electromagnetic Simulation

2012 ◽  
Vol 60 (5) ◽  
pp. 2583-2586 ◽  
Author(s):  
Rashid Mirzavand ◽  
Abdolali Abdipour ◽  
Gholamreza Moradi ◽  
Masood Movahhedi
Keyword(s):  
Electromagnetic Simulation ◽  
Unconditionally Stable ◽  
Full Wave

scholarly journals A CUDA-based GPU engine for gprMax: Open source FDTD electromagnetic simulation software

2019 ◽  
Vol 237 ◽  
pp. 208-218 ◽  
Author(s):  
Craig Warren ◽  
Antonios Giannopoulos ◽  
Alan Gray ◽  
Iraklis Giannakis ◽  
Alan Patterson ◽  
...  
Keyword(s):  
Open Source ◽  
Simulation Software ◽  
Electromagnetic Simulation
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