Modified eutectic alloys for high temperature service Semiannual progress report

Structural modification of high temperature superalloy

Modified eutectic alloys for high temperature service Six month progress report

Eutectic alloys of cobalt and nickel modified by tungsten for use at high temperature

Growth of homogeneous solid solution bismuth-antimony alloys

The inability to grow homogeneous single crystals of alloys with a large temperature gap between liquidus and solidus remains one of the major obstacles in the development of new solid state device materials

Time-resolved luminescence of low sensitivity quartz from crystalline rocks

preprintTime-resolved luminescence spectra of low sensitivity natural quartz from crystalline rocks are presented. The luminescence was pulse-stimulated at width using 470 nm blue light from quartz separated from plutonic, metamorphic, volcanic and hydrothermal samples. Measurements were made at 20 °C. All samples show evidence of a short lifetime component less than long although in several cases too weak in intensity to be evaluated accurately. On the other hand, the value of the principal lifetime component varies considerably being about in metamorphic quartz, in plutonic quartz, and in one example of hydrothermal quartz. The results illustrate a new feature of luminescence from quartz for which lifetimes less than or greater than have never been reported at room temperature before. It is argued that the thermal provenance of the quartz and so the annealing it will have experienced influences the size of the observed lifetime. In particular, the results are explained in terms of a model consisting of three luminescence centers with the dominant lifetime linked to preferential recombination at one center depending on the thermal history of the sample and hence the hole concentration of the center

Modified eutectic alloys for high temperature service Progress report

Control of modified eutectic cast alloys for high temperature servic

Management of cryptorchidism in children: guidelines

QUESTION: To develop clinical guidelines for the management of cryptorchidism in pre-pubertal boys, from early diagnosis through therapy to long-term follow-up and prognosis. METHOD: Systematic review of articles from the medical literature, referenced since 1966, using validated search strategies through the following databases: Medline, Cochrane Database of Systematic Reviews, Cochrane Register of Controlled Trials, EMBASE, DARE, ACP Journal Club, National Guidelines Clearinghouse, Guidelines International Network. Relevant articles published after 1988 were taken as the basis for the statements. Each statement was graded on the basis of the study design and on its methodological quality (GRADE approach). A multidisciplinary panel of local experts discussed and evaluated each statement on the strength of this evidence. RESULTS: 28 statements based on the best available evidence were drafted. The experts agreed with all but two statements, which were rated uncertain. CONCLUSIONS: Cryptorchidism is best diagnosed clinically, and treated by surgical orchiopexy at age 6-12 months, without a routine biopsy. If no testis is palpable, or if other signs of hypovirilisation such as hypospadias are present, the chromosomal sex and hormonal status must be assessed. Laparoscopy is the best way of diagnosing and managing intra-abdominal testes

Expectation and experience: Passenger acceptance of autonomous public transportation vehicles

Passenger acceptance is a key factor for the successful integration, uptake and use of autonomous vehicles (AVs) in the domain of public transportation. Especially knowing opinions and attitudes around safety, comfort and convenience. We discuss a pilot study conducted as part of a larger research project where AVs are being tested to transport members of the general public on a specified route with designated stops. We present preliminary findings of fieldwork conducted where people were asked their opinions and attitudes both before and after riding on an AV shuttle as a passenger for the first time. This allows us to compare user expectation beforehand with actual experience afterwards

On the Road with an Autonomous Passenger Shuttle: Integration in Public Spaces

The integration of autonomous vehicles (AVs) onto public roads presents both technical and social challenges. Public understanding and acceptance of AVs requires engagement with people who live in, work at or visit cities where they are deployed on public road networks. We investigate the impact of one of the first placements of AV passenger transport on public roadways: the Sion >. This late- breaking research presents preliminary results from interviews with local shopkeepers, residents, pedestrians and drivers to understand their attitudes and opinions of the shuttle. We also discuss video- based fieldwork that demonstrates how drivers negotiate next moves with one another through their windscreens using embodied signals such as gestures, lip-reading, and head nods to coordinate and manage a traffic situation. Finally, we consider the implications for how fully autonomous vehicles might be designed to take into account the subtle negotiations that road users engage in to coordinate with one another

Grating formation in step flow heterogeneous growth and wavelength selection induced by confinement

Based on kinetic Monte Carlo simulations, we show that modulated wires and island gratings can be formed at vicinal surfaces. The modulation (grating) wavelength along the steps can be tailored by external conditions (coverage and temperature) and intrinsic surface properties (diffusion, terrace width) via a scaling law. Above 220 K a thermodynamic saturation value for the wavelength occurs, which depends only on the terrace width. This morphological behavior can be understood in terms of nucleation arguments applied to heteroepitaxial growth of Ag on stepped Pt(111) surfaces. (C) 2004 Elsevier B.V. All rights reserved