In this paper, two professors in education share their reflections on their experience designing and implementing an International Doctoral Research Seminar at their university. Using a collaborative ...autoethnographic methodology, they consider how such seminars have the potential to provide space for emerging academics to actively engage and learn from each other in authentic and meaningful ways. Using communities of practice and transcultural pedagogies frameworks, the authors unpack the dynamics of this particular seminar, drawing on their respective reflections regarding the design and animation of this experience. Authors refer to the significance of creating a caring and open community through all phases of the seminar and mindfully cultivating a learning space that works toward creating a more inclusive and active learning culture As the authors advance implications for practice they draw on a transcultural discourse with its emphasis on engagement with other cultures in order to move beyond one's cultural and language of origin, toward the integration of different views.
By using the extension of the Minimal Geometric Deformation approach, recently developed to investigate the exterior spacetime of a self-gravitating system in the Braneworld, we identified a master ...solution for the deformation undergone by the radial metric component when time deformations are produced by bulk gravitons. A specific form for the temporal deformation is used to generate a new exterior solution with a tidal charge
Q
. The main feature of this solution is the presence of higher-order terms in the tidal charge, thus generalizing the well known tidally charged solution. The horizon of the black hole lies inside the Schwarzschild radius,
h
<
r
s
=
2
ℳ
, indicating that extra-dimensional effects weaken the gravitational field.
A comprehensive study of displacement damage and total ionisation dose effects on 4H-silicon carbide power devices is presented. Power diodes and transistors produced by different manufacturers were ...irradiated by high-energy particles (protons, alphas, electrons and neutrons). The influence of radiation on device characteristics was determined, the introduced radiation defects were identified, and the main degradation mechanisms were established. Results show that radiation leads to the creation of acceptor traps in the lightly doped drift regions of irradiated devices. Devices then degrade due to the removal of the carriers and the decrease in carrier mobility and lifetime. For unipolar devices, the gradual increase of the forward voltage is typical while the blocking characteristics remain nearly unchanged. In bipolar devices, high introduction rates of defects cause a sharp reduction of carrier lifetime. This results in shorter carrier diffusion lengths and subsequent loss of conductivity modulation leading to a sharp increase of the forward voltage drop. The irradiation also shifts the threshold voltage of power switches. That is critical, namely for metal–oxide–semiconductor field-effect transistors. According to the authors’ study, the junction barrier Schottky diode and junction field-effect transistor (JFET) can be considered the most radiation-resistant SiC power devices.
Vertical silicon carbide transistors and lateral gallium nitride (GaN) transistors for power-electronic applications currently target applications with different voltage and power ratings. Meanwhile, ...research and development activities continue on vertical GaN transistors and new gallium oxide (Ga2O3) transistors. What are their perspectives in the application and how do they compete against each other and against established transistor technologies? This study discusses the specific characteristics of lateral and vertical GaN and Ga2O3 transistors to assess their strengths and weaknesses.
This paper develops and estimates a dynamic stochastic general equilibrium (DSGE) model with sticky prices and wages for the euro area. The model incorporates various other features such as habit ...formation, costs of adjustment in capital accumulation and variable capacity utilization. It is estimated with Bayesian techniques using seven key macroeconomic variables: GDP, consumption, investment, prices, real wages, employment, and the nominal interest rate. The introduction of ten orthogonal structural shocks (including productivity, labor supply, investment, preference, cost-push, and monetary policy shocks) allows for an empirical investigation of the effects of such shocks and of their contribution to business cycle fluctuations in the euro area. Using the estimated model, we also analyze the output (real interest rate) gap, defined as the difference between the actual and model-based potential output (real interest rate).
Progress in IGBT development Niedernostheide, Franz-Josef; Schulze, Hans-Joachim; Laska, Thomas ...
IET power electronics,
04/2018, Letnik:
11, Številka:
4
Journal Article
Recenzirano
Recent progress in insulated gate bipolar transistor (IGBT) development is reviewed. Highlighted issues range from technological aspects such as special processes suitable for thin-wafer-processing, ...through the advanced cell and vertical concepts to approaches for improved IGBT ruggedness. Latest advancements regarding thermal management in both modules and discrete chips are also addressed.
Gallium nitride (GaN)-based P-channel (Pch) and N-channel (Nch) metal–oxide–semiconductor field-effect transistors (MOSFETs) with normally off operations were realised. Both Pch and Nch MOSFETs were ...monolithically fabricated in a polarisation-junction platform wafer. The platform wafer was constructed with a GaN/aluminium GaN/GaN double heterostructure, which has both two-dimensional hole gas (2DHG) and 2D electron gas (2DEG). The drain currents of Pch and Nch MOSFETs flow through 2DHG and 2DEG, respectively. The threshold gate voltages of the fabricated Pch and Nch MOSFETs were −2.7 and 6.7 V, respectively. It was shown that the threshold voltage and the on-state resistance of the Pch MOSFET can be controlled by adjusting the 2DEG potential. Furthermore, using Pch and Nch MOSFETs, complementary MOS inverter operation was demonstrated.
The volatility of economic activity in most G7 economies has moderated over the past 40 years. Also, despite large increases in trade and openness, G7 business cycles have not become more ...synchronized. After documenting these facts, we interpret G7 output data using a structural VAR that separately identifies common international shocks, the domestic effects of spillovers from foreign idiosyncratic shocks, and the effects of domestic idiosyncratic shocks. This analysis suggests that, with the exception of Japan, a significant portion of the widespread reduction in volatility is associated with a reduction in the magnitude of the common international shocks. Had the common international shocks in the 1980s and 1990s been as large as they were in the 1960s and 1970s, G7 business cycles would have been substantially more volatile and more highly synchronized than they actually were.
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