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The dynamical characteristics of electron transfer between two channels are elucidated by using a many‐particle Monte Carlo model with self‐consistent electric fields. The study has been performed to assess switching speeds associated with various novel devices such as velocity modulation transistors and dual channel high electron mobility transistors. Typical time constants for a one micrometer device (0.4 µm gate length) are 3.5 psec for the longitudinal (source‐to‐drain) and 0.2 psec for the transport perpendicular to the interfaces between the two channels.

A numerical implementation of a discretization scheme of the hydrodynamic model for submicron devices is described and applied to a one‐dimensional ballistic diode. The performance of the numerical method and the physical results of the simulation for different biases and lattice temperatures, and a brief comparison to Monte Carlo simulations, are also given.

A novel approach to many‐body quantum transport theory which emphasize the role of localized orbitals, and their lattice Fourier transforms, as dynamical basis states is given. The formalism allows for the calculations of particle quantum trajectories, describing individual elementary space and time‐dependent events in quantum processes. It is demonstrated that the particle quantum trajectories exhibit behavior quite identical to that of classical particles acted upon by a new “effective quantum force”. The present technique for calculating the quantum force can be applied to a procedure for incorporating space and time‐dependent quantum tunneling in Selfconsistent Ensembe Particle Monte Carlo (SEPMC) technique for multidimensional device analysis.

Solutions to the first three moments of the Boltzmann transport equation and Poisson's equation are obtained for a permeable base transistor (PBT) using linearized, block implicit (LBI) and ADI techniques. Two level electron transfer is considered. The results of the simulations are compared to results obtained from the drift and diffusion equations. The comparison indicates that nonequilibrium transport and velocity overshoot are important in the PBT. The predicted I‐V characteristics of the device show substantially higher current levels and a higher cutoff frequency are obtained with the moment equations.

The concept of the evolution of the distribution function is used to derive an energy‐scale distribution that is able to describe transport phenomena, including inter‐valley transfer effect, in the scale as small as the energy relaxation time. The energy‐scale distribution is used to study the evolution of electrons in n‐type GaAs under the influence of rapid change in field. Results indicate that, near the peak of strong velocity overshoot or the bottom of pronounced undershoot in the Γ valley caused by the rapid change in field, the energy‐scale distribution can not respond as fast as the distribution function calculated from the Monte Carlo method. The average velocity resulting from the energy‐scale distribution therefore leads to less pronounced overshoot and undershoot than those obtained from the Monte Carlo method. However, since velocity overshoot and undershoot are not pronounced in the L‐valleys, the L‐valley energy‐scale distribution is in excellent agreement with that determined by the Monte carlo simulation.

Standard treatments of the field emission problem typically rely on approximations to the evaluation of the Transmission Coefficient (TC). Recently, the Wigner Distribution Function (WDF) has been applied to this problem. In this paper, fast, accurate, and efficient numerical algorithms for each are presented and compared to each other and to traditional WKB and Fowler Nordheim approaches for silicon field emission. As each approach admits a trajectory interpretation, the methods for incorporating each into a larger Ensemble Particle Monte Carlo (EPMC) simulation of quantum transport are briefly discussed.

A two‐dimensional numerical computer simulation based on the analysis of the first three moments of the Boltzmann equation, known as the energy‐transport model, has been used to study various two‐dimensional effects on the performance of AlGaAs/GaAs heterostructure field‐effect transistor. The results are presented for half‐micron gate length. The calculation reveals significant electron current contribution coming from the AlGaAs region between the source and gate, contributing to the reduction of access resistance. As the electrons acquire large energies near the drain side edge of the gate, real‐space transfer to the AlGaAs region from the “two‐dimensional” electron gas channel occurs. However, at the drain end, the electron current is confined at the GaAs side of the heterointerface. The result shows insignificant current contribution from regions of depth greater than 0.048 µm into the undoped GaAs bulk. At room temperature, the results indicate transconductance, current gain cutoff frequency and power density about twice that which are calculated for “equivalent” GaAs MESFET, of identical structure and doping level as the heavily‐doped AlGaAs region. These results suggest that HEMT devices have the potential for providing significant sources of power at millimeter‐wave frequencies.

Drawing on the theory of goal systems applied to family business this case study focuses on the interdependence between non-economic goals and family goals, in order to identify if and how achieving non-economic goals generates dysfunctional behavioural patterns for family members in the long term.

This study used an inductive, 20-year longitudinal case-study based methodology.

This case study shows how the business family faces ethical/affective dimensions, struggling every day for a balance and often undermining the legitimisation and differentiation of its children. Findings show that the achievement of non-economic goals can occur to the detriment of family goals, such as by generating a dysfunctional system, specifically in business family adaptability.

The principal limitation is that this single case study evidently does not allow for complete generalization of the findings.

This case study makes a contribution to alerting the family business system to the long-term risk they face in trying to simultaneously maintain both harmony/cohesion and ethics/responsibility. Practitioners and consultants are therefore called on to help family firm owners with adopting a strategic vision by considering possible long-term counterfinal (i.e. mutually incompatible) goals.

SMEs are the most widespread type of firm in the world, and consequently dysfunctional behavioural patterns within business families represent a prominent socio-economical problem for policy makers and institutions.

This study shows that, in the long term, that which is perceived to be a desirable goal can transpire to be a dysfunctional pattern. In doing so, this research introduces a new point of view to the literature on goal systems in family business.

This paper aims to investigate and explain the power dynamics involving the mother (as the founder) and the daughter (as the successor) during the business transmission process.

This qualitative research was conducted on a sample of Italian family SMEs. The adopted approach is consistent with the narration paradigm, where the biographical features of the participant are investigated to highlight the culture, value systems and other background features.

This research suggests that if the founder is her mother, the daughter faces further challenges. Findings suggest that during business transmission, it is also important to consider the cultural and contextual factors, such as gender biases, both in the family and in the workplace. This paper seems to suggest that power is important in itself, regardless of the gender of those who exercise it.

Future research should investigate, quantitatively, the same issues considered in this research, to assess the reliability and validity of the evidence discussed here.

This paper suggests how to overcome dysfunctional dynamics in mother–daughter business transmission.

Family firms are the most widespread type of firm in the world; as a consequence, systematic failures in business transmission represent a prominent socio-economical problem for policymakers and institutions.

This research shows that in family business, power is not dynamic and does not shift among family members, as suggested by previous research. Even once the mother retires, a stable power hierarchy remains within the family firm.