Coaxial inverted geometry transistor having buried emitter

The invention relates to an inverted geometry transistor wherein the emitter is buried within the substrate. The transistor can be fabricated as a part of a monolithic integrated circuit and is particularly suited for use in applications where it is desired to employ low actuating voltages. The transistor may employ the same doping levels in the collector and emitter, so these connections can be reversed

Additional support for the TDK/MABL computer program

An advanced version of the Two-Dimensional Kinetics (TDK) computer program was developed under contract and released to the propulsion community in early 1989. Exposure of the code to this community indicated a need for improvements in certain areas. In particular, the TDK code needed to be adapted to the special requirements imposed by the Space Transportation Main Engine (STME) development program. This engine utilizes injection of the gas generator exhaust into the primary nozzle by means of a set of slots. The subsequent mixing of this secondary stream with the primary stream with finite rate chemical reaction can have a major impact on the engine performance and the thermal protection of the nozzle wall. In attempting to calculate this reacting boundary layer problem, the Mass Addition Boundary Layer (MABL) module of TDK was found to be deficient in several respects. For example, when finite rate chemistry was used to determine gas properties, (MABL-K option) the program run times became excessive because extremely small step sizes were required to maintain numerical stability. A robust solution algorithm was required so that the MABL-K option could be viable as a rocket propulsion industry design tool. Solving this problem was a primary goal of the phase 1 work effort

Selling themselves short: How inclusive is the UCAS application process to non-traditional students?

Discussions around inclusive admissions traditionally concern widening access and enabling students from underrepresented groups to enter university. However, the actual process of applying via UCAS is rarely considered. In this study, we address the question, ‘how inclusive is a UCAS personal statement?’ We consider the challenges of applying to university and writing a personal statement from the perspective of mature, former foundation students. By drawing on existing literature, personal statements and student experiences, we highlight the lack of inclusivity. The primary thesis is that the current incarnation of the personal statement needs adjustment as it is not equitable and can marginalise applicants. The study makes suggestions for improving the system and increased information, advice and guidance for applicants

Immunorecognition and immunoreceptors in the Cnidaria

Recent studies that are focused on cnidarians as model systems for cell biology are offering key insight into the complexities of higher metazoan biology. The innate immune system of these basal invertebrates is one of the cellular processes that until recently, was undescribed. The knowledge regarding both innate immunity and other cellular processes in cnidarians is far from complete. However, the evidence acquired so far, suggests highly conserved components of these cellular processes are more closely related to vertebrate homologues than more complex, but divergent invertebrate model systems. This review examines the immunorecognition and receptors that have been identified within the cnidarians so far. The complement of receptors and pathways already identified indicates that these basal invertebrates are far from “simple” in the array of methods they possess for dealing with potential invading microbes and pathogens

Performance evaluation of a kinesthetic-tactual display

Simulator studies demonstrated the feasibility of using kinesthetic-tactual (KT) displays for providing collective and cyclic command information, and suggested that KT displays may increase pilot workload capability. A dual-axis laboratory tracking task suggested that beyond reduction in visual scanning, there may be additional sensory or cognitive benefits to the use of multiple sensory modalities. Single-axis laboratory tracking tasks revealed performance with a quickened KT display to be equivalent to performance with a quickened visual display for a low frequency sum-of-sinewaves input. In contrast, an unquickened KT display was inferior to an unquickened visual display. Full scale simulator studies and/or inflight testing are recommended to determine the generality of these results

Sonic levitation apparatus

A sonic levitation apparatus is disclosed which includes a sonic transducer which generates acoustical energy responsive to the level of an electrical amplifier. A duct communicates with an acoustical chamber to deliver an oscillatory motion of air to a plenum section which contains a collimated hole structure having a plurality of parallel orifices. The collimated hole structure converts the motion of the air to a pulsed. Unidirectional stream providing enough force to levitate a material specimen. Particular application to the production of microballoons in low gravity environment is discussed