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We propose a modified discretization for the current continuity equation in the hydromodel for semiconductors. It combines ease of implementation within existing codes and robustness, even for extremely short devices. Some computational results for one and two dimensional structures are given.

An energy transport model has been numerically implemented in the device simulator HFIELDS. The transport parameters for the standard hydrodynamic model and the energy transport model are calibrated by means of DAMOCLES, a two‐dimensional Monte Carlo Boltzmann equation solver. We analyse the relative merits of these two models by comparing their predictions of the energy and velocity distributions for a bipolar transistor and a ballistic diode. In the cases presented, the hydrodynamic model is found to agree with the Monte Carlo results more closely than the energy transport model.

We discuss the device applications of a new impact ionization model. This model is based on a new formulation of the impact ionization rate for bulk semiconductors, derived from solvable high‐field Boltzmann transport equations. The model inputs are relaxation times which simulate the dominant electron‐phonon scatterings and are calibrated by realistic Monte Carlo simulations. Our impact ionization model is shown to be physically motivated and is easily implemented in the standard hydrodynamic device simulators HFIELDS and FIELDAY. An efficient numerical scheme is used to simulate three thin‐base silicon bipolar transistors. Results based on this impact ionization model are found to agree well with the experimental multiplication factors over a large range of applied voltages. These results are contrasted with the more phenomenological treatment of Scholl and Quade which is shown to be a low‐field limit of our model.

The effects of viscosity, previously neglected in electronic device stimulations, are studied using a non‐standard hydrodynamic model, following Anile and Pennisi. Results are compared with those of Gardner.

We have implemented a two‐dimensional (2D) time‐dependent hydrodynamic model suitable for studying III‐V heterostructural semiconductor devices. This we apply in simulating a heterojunction metal‐semiconductor‐metal (MSM) photodetector subject to pico‐second optical pulses. The inclusion of the energy balance equation introduces an additional time delay in the response of the detector, which is comparable to the energy relaxation time.

We present a semi‐quantum model including tunneling effects across an abrupt heterojunction. The discontinuity of the effective masses and the energy bands are considered. The quantum transmission conditions for the quasi‐Fermi levels are obtained using WKB approximation. We use mixed finite element approach and a two dimensional mesh which is double‐valued for quasi‐Fermi levels at a heterojunction. A GaAs/GaAIAs heterojunction diode is then simulated using both drift‐diffusion and semi‐quantum model by varying doping density at low temperature.

The purpose of this paper is to present the first detailed three-dimensional (3D) print from micro-computed tomography data of the skeleton of an ancient Egyptian falcon mummy.

Radiographic analysis of an ancient Egyptian falcon mummy housed at Iziko Museums of South Africa was performed using non-destructive x-ray micro-computed tomography. A 1:1 physical replica of its skeleton was printed in a polymer material (polyamide) using 3D printing technology.

The combination of high-resolution computed tomography scanning and rapid prototyping allowed us to create an accurate 1:1 model of a biological object hidden by wrappings. This model can be used to study skeletal features and morphology and also enhance exhibitions hosted within the museum.

This is the first replica of its kind made of an ancient Egyptian falcon mummy skeleton. The combination of computed tomography scanning and 3D printing has the potential to facilitate scientific research and stimulate public interest in Egyptology.

Social media – and how to use it within online educational environments – has become an immediate challenge for today's educator. Deciding on the right social media tool to adopt and its purposes in the classroom are decisions that must be approached with great care and reflection. This chapter provides examples of how social media tools are being used within the Master of Distance Education and E-learning (MDE) program at the University of Maryland University College to create and sustain an ecosystem of lifelong learning, student support, reflection, and practical research within the MDE.

A stationary 3D energy‐transport model valid for semiconductor heterostructure devices is derived from a semiclassical Boltznmann equation by the moment method. In addition to the well‐known conservation equations, we obtain original interface conditions, which are essential to have a mathematically well‐posed problem. An appropriate modelling of the physical parameters appearing in the system of equations is proposed for gallium arsenide. The model being written and its particularities mentioned, we present a novel numerical algorithm to solve it. The discretization of the equations is achieved by means of standard and mixed finite element methods. We apply the model and numerical algorithm to simulate a 2D AlGaAs/GaAs MODFET. Comparisons between expenrimental measurements and calculations are carried out. The influence of the modelling of the physical parameters, especially the electron mobility and the energy relaxation time, is noted. The results show the satisfactory behaviour of our model and numerical algorithm when applied to GaAs heterostructure devices.

This paper presents a new discretization technique of the hydrodynamic energy balance model based on a finite‐element formulation. The concept of heat source lumping is introduced, and the thermal conductivity model includes the effect of varying both carrier concentrations and temperatures. The energy balance equation is formulated to account for kinetic energy as a convective flow. The new discretization method has the advantage that it allows for assembling the functions out of elementary variables available over elements instead of along element links. Therefore, theoretically, calculation of the Jacobian should be three times faster than by the classic method. Results are given for three examples. The method suffers from mathematical instabilities, but provides a good basis for future work to solve these problems.