Parametric study of manned life support systems. Volume 1 - Summary Final report, Jul. 1967 - Aug. 1968

Summary data on methodology, mission and vehicle criteria for parametric study of manned life support system

Process improvement in BAe Systems and the wider aerospace sector

Purpose: To research the change management processes used to implement ‘world class’ improvements in a major aerospace company, BAE SYSTEMS, and to propose a model for process improvement in the wider aerospace sector. Design/methodology/approach: The research was undertaken as a longitudinal study over a period of five years. A variety of research methodologies were used at various stages of the research including action research and observation. Semi-structured and unstructured interviews were used to gather qualitative data along with documentary evidence of the processes being used. Findings: There are three key findings. Firstly, an understanding of the production stages in the aerospace sector: future project; new product; sustain and return to work. Secondly details of a matrix-based approach and the issues regarding its implementation in a large organisation are discussed. Thirdly, a generic set of principles to aid process improvement in the aerospace sector is proposed. Research limitations/implications: Given that the study is based in one company, there are issues regarding the generalisation of the results. A potential further research project would entail the implementation of the proposed generic principles in another aerospace organisation. Practical implications: For BAE SYSTEMS, this research project aided their understanding of the issues involved in rolling out a process improvement program in a large organisation.Originality/value: Until recently, most of the research into process improvement had either been universalistic or aimed at another type of industry, such as the automotive industry. This research helps to address the specific needs of the aerospace industry

Monte Carlo investigation of optimal device architectures for SiGe FETs

Strained silicon channel FETs grown on virtual SiGe substrates show clear potential for RF applications, in a material system compatible with silicon VLSI. However, the optimisation of practical RF devices requires some care. 0.1-0.12 μm gate length designs are investigated using Monte Carlo techniques. Although structures based on III-V experience show fT values of up to 94 GHz, more realistic designs are shown to be limited by parallel conduction and ill constrained effective channel lengths. Aggressively scaled SiGe devices, following state-of-the-art CMOS technologies, show fT values of up to 80 GHz

New broad 8Be nuclear resonances

Energies, total and partial widths, and reduced width amplitudes of 8Be resonances up to an excitation energy of 26 MeV are extracted from a coupled channel analysis of experimental data. The presence of an extremely broad J^pi = 2^+ ``intruder'' resonance is confirmed, while a new 1^+ and very broad 4^+ resonance are discovered. A previously known 22 MeV 2^+ resonance is likely resolved into two resonances. The experimental J^pi T = 3^(+)? resonance at 22 MeV is determined to be 3^-0, and the experimental 1^-? (at 19 MeV) and 4^-? resonances to be isospin 0.Comment: 16 pages, LaTe

Analytical simulation of the Langley Research Center integrated life-support system, volume 1

Analytical simulation of integrated life support system and oxygen recovery syste

A two-stage stochastic programming with recourse model for determining robust planting plans in horticulture

A two-stage stochastic programming with recourse model for the problem of determining optimal planting plans for a vegetable crop is presented in this paper. Uncertainty caused by factors such as weather on yields is a major influence on many systems arising in horticulture. Traditional linear programming models are generally unsatisfactory in dealing with the uncertainty and produce solutions that are considered to involve an unacceptable level of risk. The first stage of the model relates to finding a planting plan which is common to all scenarios and the second stage is concerned with deriving a harvesting schedule for each scenario. Solutions are obtained for a range of risk aversion factors that not only result in greater expected profit compared to the corresponding deterministic model, but also are more robust

RF analysis methodology for Si and SiGe FETs based on transient Monte Carlo simulation

A comprehensive analysis methodology allowing investigation of the RF performance of Si and strained Si:SiGe MOSFETs is presented. It is based on transient ensemble Monte Carlo simulation which correctly describes device transport, and employs a finite element solver to account for complex device geometries. Transfer characteristics and figures of merit for a number of existing and proposed RF MOSFETs are discussed

An e-learning tool for understanding schedule properties

In this paper, we describe an e-learning tool that we have developed to assist University students studying various modules on database systems. We use the acronym DTST (viz. a learning tool for Database Transaction Schedule Testing) to refer to our learning tool. DTST enables students to actively construct their own learning environment, it can respond in an individualistic way to student input, and it has a built-in web interface that makes it widely accessible. Field tests conducted on DTST suggest that it provides students with a different and valuable type of learning experience that traditional methods do not provide

A database transaction scheduling tool in Prolog

In this paper, we describe an item of "intelligent" educational software that is intended to help students taking university computer science courses to understand the fundamentals of transaction scheduling. The software, implemented in PROLOG, empowers students to construct their own learning environment and is able to provide tailored forms of feedback to different types of learner. We describe the development and evaluation of the software, and we present details of the analysis of the results of our investigation into the effectiveness of the software as a teaching and learning tool. Our results suggest that our learning tool provides students with a different and valuable type of learning experience, which traditional methods do not provide