A berthing and fastening strategy for orbital replacement units

Research in the area of berthing of Orbital Replacement Units (ORU's) at the GSFC consists of two major parts. First, we concentrate on the development of a comprehensive fastening strategy that can provide both mechanical as well as electrical connection to the ORU. Second, our efforts in robot collision avoidance and motion planning have led to the development of a state-of-the-art capacitive proximity sensor with associated motion control algorithms. These efforts combine to produce a system that allows safe and reliable machine assisted berthing. Although our main emphasis was on berthing of ORU's, we believe that some of our results can also be applied to docking

A berthing and fastening strategy for orbital replacement units

A summary of the GSFC applied research effort in robotic berthing is provided. The summary includes several demonstrations and experimental highlights illustrated on video. Two GSFC developments are central to the research, the 'Capaciflector' sensor and the 'Spline-Locking Screw fastener

Stopping powers and cross sections due to two-photon processes in relativistic nucleus-nucleus collision

The radiation dose received from high energy galactic cosmic rays (GCR) is a limiting factor in the design of long duration space flights and the building of lunar and martian habitats. It is of vital importance to have an accurate understanding of the interactions of GCR in order to assess the radiation environment that the astronauts will be exposed to. Although previous studies have concentrated on the strong interaction process in GCR, there are also very large effects due to electromagnetic (EM) interactions. In this report we describe our first efforts at understanding these EM production processes due to two-photon collisions. More specifically, we shall consider particle production processes in relativistic heavy ion collisions (RHICs) through two-photon exchange

The elastic-plastic behaviour of some axisymmetric pressure vessel heads and nozzles

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VLA Observations of a Complete Sample of Radio Loud Quasars between redshifts 2.5 and 5.28: I. high-redshift sample summary and the radio images

We present high resolution (arcsecond or better) observations made with the Karl G. Jansky Very Large Array of 123 radio-loud quasars with redshifts in the range $2.5 \leq z \leq 5.28$ that form a complete flux limited sample ($\geq 70$ mJy at 1.4 GHz or 5 GHz). Where possible, we used previous high resolution VLA observations (mainly A array at 1.4, 5 and 8 GHz) from the NRAO archive and re-imaged them (43 sources). For the remainder, new observations were made in the A array at 1.4 and 5 GHz. We show images of the 61 resolved sources, and list structural properties of all of them. Optical data from the SDSS are available for nearly every source. This work represents a significant increase in the number of high redshift quasars with published radio structures, and will be used to study the properties and evolution of luminous radio sources in the high redshift universe

Data-driven through-life costing to support product lifecycle management solutions in innovative product development

Innovative product usually refers to product that comprises of creativity and new ideas. In the development of such a new product, there is often a lack of historical knowledge and data available to be used to perform cost estimation accurately. This is due to the fact that traditional cost estimation methods are used to predict costs only after a product model has been built, and not at an early design stage when there is little data and information available. In light of this, original equipment manufacturers are also facing critical challenges of becoming globally competitive and increasing demands from customer for continuous innovation. To alleviate these situations this research has identified a new approach to cost modelling with the inclusion of product lifecycle management solutions to address innovative product development.The aim of this paper, therefore, is to discuss methods of developing an extended-enterprise data-driven through-life cost estimating method for innovative product development

Population Ageing and Government Health Expenditures in New Zealand, 1951-2051

The paper uses a simulation model to assess the effects of population ageing on government health expenditures in New Zealand. Population ageing is defined to include disability trends and “distance to death”; government health expenditures are defined to include both acute and long-term care. The model results suggest that population ageing is associated with a large increase in expenditure share of people aged 65 and over, which rises from about 29% of total government health expenditure in 1951 to 63% in 2051. Analysis of demographic and health trends over the period 1951 to 2002 suggests, however, that these trends account for only a small proportion of the total growth in health expenditure. Most expenditure growth is attributable to other factors, such as an expansion in the range of treatments provided, and increases in input prices such as wages. Growth in this non-demographic component of health expenditures has reached 3-4% per year over recent years. Projection results for the period 2002 to 2051 suggest that restraining government expenditure on health to 6-12% of GDP would require long-run growth rates for the non-demographic component of health expenditure that are significantly lower than current rates. In other words, future demographic changes may be less threatening than is often assumed, but it would still not be possible to maintain current growth rates for government health expenditure and avoid substantial increases in the ratio between expenditure and GDP.Fiscal projections; Government health expenditure; Health status; New Zealand