Height-width proportion and stroke width in numeral visibility.

Each of 12 groups of 6 Ss viewed under tachistoscopic exposure numerals in one of 12 possible combinations of 4 height-width proportions and 3 stroke widths. "1. Height-width proportion was a source of variation in visibility significant beyond the 1% level for five numerals, and beyond the 5% level for a sixth. 2. Stroke width was a significant source of variation for only one numeral. 3. The most visible combination… for all numerals is a height-width ratio of 10:7.5 and a stroke width to height ratio of 1:10." (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Ultrasonic consolidation for embedding SMA fibres within aluminium matrices

For this paper, adaptive composites will be considered as structural materials for advanced aerospace applications which have the ability to measure and respond to external stimuli by adapting the structure accordingly, through embedded active or passive functional elements. The intention of this project was targeted at the fabrication of adaptive composites using a novel layered manufacturing technique called ultrasonic consolidation (UC). This paper details the initial study of this research to identify plastic deformation of the matrix material around shape memory alloy (SMA) fibres, and bond quality, based on the microscopic observation and mechanical test results obtained. The embedding method, considered during this study, has successfully produced laminate specimens, with full consolidation, within seconds, using low oscillation amplitude and low contact pressures (<300 kPa). This work will report on the identification of the bonding characteristics for these SMA fibres when embedded in aluminium alloy 3003 specimens.     

Evaluation of the isotope dilution technique for determining ileal endogenous nitrogen excretion in the rat

Three body amino acid pools (plasma free, plasma bound and small intestinal tissue) were evaluated as precursors to allow measurement using the isotope dilution technique of endogenous excretion at the terminal ileum of animals. Eighteen 150-g bodyweight rats were given either a protein-free, an enzyme-hydrolysed casein based or a synthetic amino acid based diet, and digesta were collected from the terminal ileum. The animals had been subjected to a constant 8-day infusion of tritiated leucine via subcutaneously implanted osmotic mini pumps. Specific activities (dpm nM^?1 leucine) of the ileal digesta and the plasma free, plasma bound and small intestinal tissue pools were determined and the specific activity for the ileal digesta was expressed as a proportion of the respective precursor pool value to give dilution factors for each dietary treatment. For the protein-free diet, where the ileal nitrogenous flow is endogenous by definition, the dilution factor for an appropriate precursor pool would be unity. For the hydrolysed casein and synthetic amino acid diets, in which the peptides and amino acids are expected to be virtually completely absorbed anterior to the ileum, high dilution factors (close to unity) would be expected. The mean dilution factors based on the plasma free amino acid pool were untenably low (0-2 to 0-3). For the plasma bound amino acid pool mean dilution factors of 1-3 were found for animals given the protein-free and synthetic amino acid diets, while a lower value (0-7) was obtained for the hydrolysed casein treatment. Untenably high factors (1-5) were found with the small intestinal tissue for the protein-free and synthetic amino acid treatments, while the corresponding value for the hydrolysed caseinfed rats was unity. The dilution factor data within treatments were highly variable, and none of the pools examined gave consistently reliable results and could thus be accepted as a valid precursor pool for the endogenous proteins.     

A spectrofluorimetric assay of the tryptophan content of feedstuffs

A method for the analysis of the tryptophan content of feedstuffs employing sodium hydroxide hydrolysis followed by the spectrofluorimetric estimation of tryptophan is described. Provided the development of the fluorophore is carried out in the absence of light, satisfactory results for a wide range of feedstuffs are obtained.     

Method for embedding optical fibers in an aluminum matrix by ultrasonic consolidation

The overall aim of the research, part of which is outlined in this paper, was to utilize the ultrasonic consolidation (UC) process for the fabrication of smart metal structures, capable of measuring an external stimulus and responding to this stimulus by adapting its structure accordingly through embedding both active and passive functional elements. This paper presents a fundamental study of embedding methods for the fabrication of optical fibers embedded within aluminum structures. The methods considered in this paper produced embedded optical fiber specimens in which large amounts of plastic flow were observed within the matrix. The matrix material deformed around the fibers, resulting in fully embedded optical fibers capable of transmitting a bright light source and without damaging the fibers. Based on light responses, a general process window was drawn to show the range at which optical fibers can be embedded within aluminum structures using the UC process. The outcomes lay down initial investigative principles for the further development of the technology for embedding or cladding of optical fiber sensors, such as fiber Bragg grating devices, within or on metal structures: for example, the cladding of large free-form metal structures or smart "skinned" metal foam or metal honeycomb structures.     

The potential of information and communication technologies to support ageing and independent living

This paper discusses the potential of Information and Communications Technology to support ageing and independent living. It reports on the expected impact of ageing Baby Boomers, the environment for ageing, chronic illness and other challenges of ageing, developments in Smart Homes and Assistive Technologies and on the available research evidence of the benefits.     

The Role of Additive Manufacturing and Physiomimetic Computational Design for Digital Construction

The recent adoption of the term additive manufacturing (AM) to describe a broad range of digital ‘layer by layer’ fabrication techniques comes 20 years since its inception and more than 10 years since architectural practices engaged with the technology for making prototypes and models. Soon this technology will join existing CNC subtractive and formative processes within the volume and mass-market sectors, where design complexity and increased functionality result in competitive advantage. It is also about a decade since researchers proposed additive manufacturing for construction. Rupert Soar and David Andreen introduce here the different construction-scale additive manufacturing systems currently in development. If linked to physiomimetic computational design strategies, these technologies provide novel possibilities for addressing architecture's manufacturing challenges in the face of energy expenditure, material resources and environmental impact. Copyright © 2012 John Wiley & Sons, Ltd.     

Influence of sonotrode texture on the performance of an ultrasonic consolidation machine and the interfacial bond strength

Ultrasonic consolidation (UC) has been successfully used in rapid tooling, prototyping and moulding, fibre and sensor embedding, and electronics embedding. To ensure consistent transfer of ultrasonic energy into workpieces, the surface texture of sonotrode is very important. This paper studied the effects and importance of the texture on the UC process. Monolithic Al 3003 H18 samples were consolidated by the alpha ultrasonic weld machine with a worn sonotrode and a newly electrical discharge machining (EDM)-modified sonotrode, and during the process the performance of the UC machine was monitored. Peel tests were conducted for the consolidated samples and the peel strength and linear weld density were compared. As expected, the results showed that UC machine performance improved with the EDM-modified sonotrode. After improving the surface texture of sonotrode, problems such as foil overlap and crinkling were solved. The results showed that an even and rough texture was necessary for the UC machine to achieve a good performance and a high energy transmission efficiency and the surface roughness of sonotrode may have a two-side influence, i.e. increasing void level and introducing more energy, on consolidation.     

Personal history data as a predictor of success in service station management.

For a sample of 29 dealers, ratings on 15 aspects of service station management were reduced to a single over-all rating that was used as a criterion against which a personal history blank was item analyzed using a variant of double cross validation. The scoring key was then cross-validated on a new sample of 23 dealers. It was concluded that the unitary criterion was adequate to describe performance, and that 14 of the 39 items in the blank discriminated more successful dealers from less successful, retaining validity on cross-validation. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Stroke width, illumination level, and figure-ground contrast in numeral visibility.

Two levels each of three numeral visibility variables (stroke width to height ratios of 1:4 and 1:16; illumination level of 0.5 foot-candles and 500 foot-candles; mode of figure-ground contrast-black numbers on white background and the reverse) were studied in a 2 X 2 X 2 analysis of variance, using 40 Ss who provided 5 replications of each possible condition. Of the main effects, only illumination level showed a significant effect on visibility. Stroke width interacted significantly with both illumination level and mode of figure-ground contrast, but the latter two variables did not interact. The interaction of all three variables was also significant. (PsycINFO Database Record (c) 2010 APA, all rights reserved)