Research study of structural damage produced in silicon semiconductors by neutron irradiation Final report, Jun. 1969 - Jul. 1970

Characteristics of damage produced in silicon semiconductors by neutron irradiatio

The Investment Comparison Tool (ICT): A Method to Assess Research and Development Investments

This paper presents a software tool (the Investment Comparison Tool), a methodology (the Investment Comparison Methodology), and a decision support system (the Investment Comparison System) to aid decision makers with Research and Development Investment allocations. The Investment Comparison System (ICS) can be used vertically within an organization and horizontally across organizations at multiple portfolio investment levels. The ICS is applicable to any R&D environment ranging from Industry Research Environments to Federal Agencies. The ICS described in this paper is comprised of a system architecture, databases, Group Decision Making (GDM) methods, an Investment Comparison Tool (ICT) that includes various algorithms, and reporting tools. To aid in the usage of the ICS, an Assessment and Evaluation Framework, a detailed methodology with its technical foundation, and a corresponding example are also presented. The decision making process used in the methodology is the Analytical Hierarchy Process combined with methods for GDM. ICS is unique because of how it uses a combination of algorithms for assessing R&D Investments and the wide flexibility of its use

A New Statistical Procedure for Validation of Simulation and Stochastic Models

We describe a new statistical procedure for validating simulation and analytic stochastic models using hypothesis testing when the amount of model accuracy is specified. This procedure provides for the model to be accepted if the difference between the system and the model outputs are within the specified ranges of accuracy. The system must be observable to allow data to be collected for validation

Effect of configuration variation on externally blown flap noise

The sensitivity of flap interaction noise to variations in engine-under-the-wing externally blown flap geometry was investigated with a large cold-flow model. Both 2- and 3-flap wing sections (7-ft chord) with trailing flap angles up to 60 deg were employed. Exhaust nozzles included coaxial, plug, and 8- and 13-inch diameter conical configurations. These nozzles were tested at two positions below the wing. The effects of these geometry variations on noise level, directivity, and spectral shape are summarized in terms of exhaust flow parameters evaluated at the nozzle exit and at the flap impingement station. The results are also compared with limited flap noise data available from tests using real engines

Managing expectations and fiscal policy

This paper studies an optimal fiscal policy problem of Lucas and Stokey (1983) but in a situation in which the representative agent's distrust of the probability model for government expenditures puts model uncertainty premia into history-contingent prices. This situation gives rise to a motive for expectation management that is absent within rational expectations and a novel incentive for the planner to smooth the shadow value of the agent's subjective beliefs to manipulate the equilibrium price of government debt. Unlike the Lucas and Stokey (1983) model, the optimal allocation, tax rate, and debt become history dependent despite complete markets and Markov government expenditures.

Research study of structural damage produced in silicon semiconductors by neutron irradiation Semiannual report

Etching techniques for undoped and lithium doped silicon solar cells and observation by surface replication and thin film transmission electron microscop

How cold is cold dark matter? Small scales constraints from the flux power spectrum of the high-redshift Lyman-alpha forest

We present constraints on the mass of warm dark matter (WDM) particles derived from the Lyman-alpha flux power spectrum of 55 high- resolution HIRES spectra at 2.0 < z < 6.4. From the HIRES spectra, we obtain a lower limit of mwdm > 1.2 keV 2 sigma if the WDM consists of early decoupled thermal relics and mwdm > 5.6 keV (2 sigma) for sterile neutrinos. Adding the Sloan Digital Sky Survey Lyman-alpha flux power spectrum, we get mwdm > 4 keV and mwdm > 28 keV (2 sigma) for thermal relics and sterile neutrinos. These results improve previous constraints by a factor two.Comment: Some issues clarified (especially resolution related). Conclusions unchanged. Accepted version by PR

IRAS 16293-2422: A very young binary system?

We present 4".5 x 2".5 resolution millimeter wavelength observations of the young far-infrared source IRAS 16293-2422 which resolve the continuum emission into two sources, MM 1 and MM 2. These sources coincide with known radio continuum sources and may constitute a very young binary system with a projected separation of 840 AU. Flux measurements from 18 cm to 25 μm show that the majority of the millimeter wavelength emission arises from dust within 300 AU of the individual central objects. The total dynamical mass of 1.1-1.3 M_⊙, coupled with our mass estimates for MM 1 and MM 2, suggests that the mass in circumstellar material is comparable to that of the central stellar cores. Since the stellar masses are constrained to be ≤ 0.5 M_⊙ each, it is likely that the bolometric luminosity of 30-40 L_⊙ is derived mainly from accretion of the observed circumstellar material. Maps of the J = 2, 3-1, 2 transition of SO obtained simultaneously show that this emission is centered on MM 1, with weaker emission in a clumpy distribution to the east and west. No SO emission is detected toward MM 2, indicating an upper limit to the fractional abundance which is a factor of 10 below that toward MM 1. We propose that the SO emission toward MM 1 is a result of the outflow activity associated with this source and that the outlying emission clumps trace regions of mild interaction between the outflow and the ambient cloud

Using intervention mapping to develop a culturally appropriate intervention to prevent childhood obesity: the HAPPY (Healthy and Active Parenting Programme for Early Years) study.

INTRODUCTION: Interventions that make extensive use of theory tend to have larger effects on behaviour. The Intervention Mapping (IM) framework incorporates theory into intervention design, implementation and evaluation, and was applied to the development of a community-based childhood obesity prevention intervention for a multi-ethnic population. METHODS: IM was applied as follows: 1) Needs assessment of the community and culture; consideration of evidence-base, policy and practice; 2) Identification of desired outcomes and change objectives following identification of barriers to behaviour change mapped alongside psychological determinants (e.g. knowledge, self-efficacy, intention); 3) Selection of theory-based methods and practical applications to address barriers to behaviour change (e.g., strategies for responsive feeding); 4) Design of the intervention by developing evidence-based interactive activities and resources (e.g., visual aids to show babies stomach size). The activities were integrated into an existing parenting programme; 5) Adoption and implementation: parenting practitioners were trained by healthcare professionals to deliver the programme within Children Centres. RESULTS: HAPPY (Healthy and Active Parenting Programme for Early Years) is aimed at overweight and obese pregnant women (BMI > 25); consists of 12 × 2.5 hr. sessions (6 ante-natal from 24 weeks; 6 postnatal up to 9 months); it addresses mother's diet and physical activity, breast or bottle feeding, infant diet and parental feeding practices, and infant physical activity. CONCLUSION: We have demonstrated that IM is a feasible and helpful method for providing an evidence based and theoretical structure to a complex health behaviour change intervention. The next stage will be to assess the impact of the intervention on behaviour change and clinical factors associated with childhood obesity. The HAPPY programme is currently being tested as part of a randomised controlled feasibility trial