Hardening and non-associated flow NURBS plasticity.

In numerical analysis the failure of engineering materials is controlled through specifying yield envelopes (or surfaces) that bound the allowable stress in the material. Simple examples include the prismatic von Mises (circle) and Tresca (hexagon) yield surfaces. However, each surface is distinct and requires a specific equation describing the shape of the surface to be formulated in each case. These equations impact on the numerical implementation (specifically relating to stress integration) of the models and therefore a separate algorithm must be constructed for each model. Recently a framework was proposed that allows any isotropic yield surface to be represented by a NURBS surface and the constitutive model formulated using the name numerical algorithm. This paper presents, for the first time, an extension to this framework to allow both hardening (expansion/contraction of the surfaces) and a non-associated plastic flow rule. As with previous work on NURBS plasticity, the constitutive framework is combined with an implicit backward-Euler-type stress integration algorithm. The numerical performance of the algorithm is demonstrated using both material point investigations and boundary value simulations

Optimal filtering of the LISA data

The LISA time-delay-interferometry responses to a gravitational-wave signal are rewritten in a form that accounts for the motion of the LISA constellation around the Sun; the responses are given in closed analytic forms valid for any frequency in the band accessible to LISA. We then present a complete procedure, based on the principle of maximum likelihood, to search for stellar-mass binary systems in the LISA data. We define the required optimal filters, the amplitude-maximized detection statistic (analogous to the F statistic used in pulsar searches with ground-based interferometers), and discuss the false-alarm and detection probabilities. We test the procedure in numerical simulations of gravitational-wave detection.Comment: RevTeX4, 28 pages, 9 EPS figures. Minus signs fixed in Eq. (46) and Table II. Corrected discussion of F-statistic distribution in Sec. IV

Remote Sensing D/H Ratios in Methane Ice: Temperature-Dependent Absorption Coefficients of CH3D in Methane Ice and in Nitrogen Ice

The existence of strong absorption bands of singly deuterated methane (CH3D) at wavelengths where normal methane (CH4) absorbs comparatively weakly could enable remote measurement of D/H ratios in methane ice on outer solar system bodies. We performed laboratory transmission spectroscopy experiments, recording spectra at wavelengths from 1 to 6 \mum to study CH3D bands at 2.47, 2.87, and 4.56 \mum, wavelengths where ordinary methane absorption is weak. We report temperature-dependent absorption coefficients of these bands when the CH3D is diluted in CH4 ice and also when it is dissolved in N2 ice, and describe how these absorption coefficients can be combined with data from the literature to simulate arbitrary D/H ratio absorption coefficients for CH4 ice and for CH4 in N2 ice. We anticipate these results motivating new telescopic observations to measure D/H ratios in CH4 ice on Triton, Pluto, Eris, and Makemake.Comment: 17 pages, 7 figure

Flamingo Vol. I N 3

Voo-Doo. Untitled. Prose. 1. Widow. Untitled. Prose. 1. Tiger. Untitled. Prose. 1. Purple Cow. Untitled. Prose. 1. Anonymous. Untitled. Prose. 1. Life. Untitled. Prose. 2. Yale Record. Untitled. Prose. 2. Voo-Doo. Untitled. Prose. 2. Sour Owl. Untitled. Prose. 2. Puppet. Untitled. Prose. 2. Sun Dial. Untitled. Prose. 2. Anonymous. Untitled. Prose. 2. Nottingham, Ruth. Teddy . Prose. 5. Grogan. Untitled. Picture. 7. Anonymous. Untitled. Prose. 7. Anonymous. An Easy One . Prose. 7. Anonymous. How Terrible! Prose. 7. Anonymous. Untitled. Prose. 7. Anonymous. Untitled. Poem. 7. F.H.G. Untitled. Picture. 7. Wood, J.E.F. When mother Went to College . Prose. 8. E.D.T. Chicago Corn Exchange . Poem. 8. Anonymous. Untitled. Prose. 8. Anonymous. Untitled. Poem. 8. Anonymous. All But . Prose. 8. R.D.B. Roscoe to The Rescue . Prose. 9. Leet, L.D. On The Efficacy of Dreams . Prose. 10. Orange Ade. The Fable of the Coffin Nailer . Prose. 11. Orange Ade. Time Wasted . Prose. 11. Orange Ade. The Americanized Boy . Prose. 11. Orange Ade. Anything to Oblige . Prose. 11. Orange Ade. Tit For Tat . Prose. 11. Orange Ade. Good Alibi . Prose. 11. Orange Ade. Untitled. Prose. 11. Grogan. Untitled. Picture. 11. Lusk, R.G. On The Absurdity of Catching Fish When A-Fishing . Prose. 12. Anonymous. Co-eds and Plain Eds in 1950 . Picture. 13. Potter, W.M. Letters of A Japanese Sandman . Prose. 13. Anonymous. Ex Facultate . Prose. 13. Anonymous. Untitled. Prose. 13. R.J.S. An Uplifting Influence . Picture. 13. Anonymous. Consider the Luxite Girl . Poem. 14. Anonymous. Shades of Orpheus . Poem. 14. Anonymous. With The Gospel Team . Poem. 14. Anonymous. Untitled. Prose. 14. Anonymous. Untitled. Poem. 14. Anonymous. A Dirty Trick . Prose. 14. Taylor, Elsie D. Vestigial Customs . Prose. 15. Anonymous. Untitled. Prose. 16. Anonymous. A New version of Anthropology . Prose. 18. Anonymous. A New version of Anthropology . Picture. 18. Anonymous. Untitled. Prose. 18. Funk, Dorothy K. Untitled. Picture. 18. Anonymous. A Deep one . Prose. 18. Anonymous. Take His Name . Prose. 18. Olney, Clarke. The Evolution of An Intellectual . Prose. 19. Anonymous. Untitled. Prose. 19. Anonymous. Untitled. Prose. 20. W.A.W. On Getting Up For Breakfast . Prose. 20. McCann. Untitled. Picture. 21. Anonymous. Untitled. Prose. 21. Anonymous. S.S.S. . Prose. 21. Anonymous. The Judge Disagreed . Prose. 21. Anonymous. The Modern Woman . Prose. 21. Anonymous. Denison Slang in Japan . Prose. 22. Anonymous. Being Specific . Prose. 22. Anonymous. Then The Fun Began . Prose. 22. Anonymous. Then The Fun Began . Prose. 22. Anonymous. Chess Nuts . Poem. 22. Anonymous. Chess Nuts . Picture. 22. Funk, Dorothy K. Untitled. Picture. 22. Anonymous. Untitled. Prose. 22. Reel, Virginia. Untitled. Prose. 22. Anonymous. Untitled. Prose. 23. Anonymous. Take This to Heart . Prose. 23. Anonymous. Stepping Out . Picture. 23. Olney, Clarke. Untitled. Picture. 23. Anonymous. To Lalage . Prose. 23. Anonymous. Untitled. Poem. 24. Anonymous. Description of the Day . Prose. 25. Anonymous. Untitled. Prose. 25. Voo-Doo. Good Bizziness . Prose. 26. Anonymous. Fore! . Prose. 26. Anonymous. Untitled. Prose. 26. Brelsford, Ernest C. Souveniring . Prose. 27. Anonymous. Untitled. Prose. 30. Burr. Sweet Dreams . Prose. 30. Jester. Untitled. Prose. 30. Judge. Untitled. Prose. 30. Goblin. Untitled. Prose. 30. Cracker. Sanitation . Poem. 32. Anonymous. Untitled. Prose. 32. Jester. Untitled. Prose. 32. Goblin. Untitled. Prose. 32. Record. Untitled. Prose. 32. Linotype. Untitled. Prose. 32. Holt, Kilburn. The Schemer\u27s Lament . Poem. 7. Owen, Ernest t. Mother . Poem. 3. Owen, Ernest T. To--- . Poem. 24

Talented suppliers? Strategic change and innovation in the UK aerospace industry

The 1990s marked the start of extensive re-structuring in the aerospace industry throughout the world. While the ensuing consolidation among prime contractors has been widely researched, the changes affecting the aerospace supply chain have received less attention. This study focuses on the re-structuring taking place within the supply chain of the UK aerospace industry. The findings point to extensive re-structuring. Unlike most earlier studies the lean supply model was found to be a powerful influence, with suppliers moving away from subcontractor status and instead taking on the mantle of ‘talented’ suppliers. While some of the implications of lean supply, in terms of the dynamics of innovation, were not apparent, there were modest signs of increased process innovation on the part of some suppliers

Junior staffing changes and the temporal ecology of adverse incidents in acute psychiatric wards

Aim.  This paper reports an examination of the relationship between adverse incident rates, the arrival of new junior staff on wards, and days of the week on acute psychiatric wards. Background.  Incidents of violence, absconding and self-harm in acute inpatient services pose risks to patients and staff. Previous research suggests that the arrival of inexperienced new staff may trigger more adverse incidents. Findings on the relationship between incidents and the weekly routine are inconsistent. Method.  A retrospective analysis was conducted of formally reported incident rates, records of nursing student allocations and junior doctor rotation patterns, using Poisson Regression. Variance between days of the week was explored using contingency table analysis. The data covered 30 months on 17 psychiatric wards, and were collected in 2002–2004. Findings.  The arrival of new and inexperienced staff on the wards was not associated with increases in adverse incident rates. Most types of incidents were less frequent at weekends and midweek. Incident rates were unchanged on ward-round days, but increased rates were found on the days before and after ward rounds. Conclusion.  Increased patient tension is associated with raised incident rates. It may be possible to reduce incident rates by moderating stimulation in the environment and by mobilizing support for patients during critical periods

The composition of the protosolar disk and the formation conditions for comets

Conditions in the protosolar nebula have left their mark in the composition of cometary volatiles, thought to be some of the most pristine material in the solar system. Cometary compositions represent the end point of processing that began in the parent molecular cloud core and continued through the collapse of that core to form the protosun and the solar nebula, and finally during the evolution of the solar nebula itself as the cometary bodies were accreting. Disentangling the effects of the various epochs on the final composition of a comet is complicated. But comets are not the only source of information about the solar nebula. Protostellar disks around young stars similar to the protosun provide a way of investigating the evolution of disks similar to the solar nebula while they are in the process of evolving to form their own solar systems. In this way we can learn about the physical and chemical conditions under which comets formed, and about the types of dynamical processing that shaped the solar system we see today. This paper summarizes some recent contributions to our understanding of both cometary volatiles and the composition, structure and evolution of protostellar disks.Comment: To appear in Space Science Reviews. The final publication is available at Springer via http://dx.doi.org/10.1007/s11214-015-0167-

Near-Infrared Spectral Monitoring of Triton with IRTF/SpeX II: Spatial Distribution and Evolution of Ices

This report arises from an ongoing program to monitor Neptune's largest moon Triton spectroscopically in the 0.8 to 2.4 micron range using IRTF/SpeX. Our objective is to search for changes on Triton's surface as witnessed by changes in the infrared absorption bands of its surface ices N2, CH4, H2O, CO, and CO2. We have recorded infrared spectra of Triton on 53 nights over the ten apparitions from 2000 through 2009. The data generally confirm our previously reported diurnal spectral variations of the ice absorption bands (Grundy & Young 2004). Nitrogen ice shows a large amplitude variation, with much stronger absorption on Triton's Neptune-facing hemisphere. We present evidence for seasonal evolution of Triton's N2 ice: the 2.15 micron absorption band appears to be diminishing, especially on the Neptune-facing hemisphere. Although it is mostly dissolved in N2 ice, Triton's CH4 ice shows a very different longitudinal variation from the N2 ice, challenging assumptions of how the two ices behave. Unlike Triton's CH4 ice, the CO ice does exhibit longitudinal variation very similar to the N2 ice, implying that CO and N2 condense and sublimate together, maintaining a consistent mixing ratio. Absorptions by H2O and CO2 ices show negligible variation as Triton rotates, implying very uniform and/or high latitude spatial distributions for those two non-volatile ices.Comment: 22 pages, 13 figures, 5 tables, to appear in Icaru

Search for single top quarks in the tau+jets channel using 4.8 fb−1^{-1} of ppˉp\bar{p} collision data

We present the first direct search for single top quark production using tau leptons. The search is based on 4.8 fb$^{-1}$ of integrated luminosity collected in $p\bar{p}$ collisions at $\sqrt{s}$=1.96 TeV with the D0 detector at the Fermilab Tevatron Collider. We select events with a final state including an isolated tau lepton, missing transverse energy, two or three jets, one or two of them $b$ tagged. We use a multivariate technique to discriminate signal from background. The number of events observed in data in this final state is consistent with the signal plus background expectation. We set in the tau+jets channel an upper limit on the single top quark cross section of \TauLimObs pb at the 95% C.L. This measurement allows a gain of 4% in expected sensitivity for the observation of single top production when combining it with electron+jets and muon+jets channels already published by the D0 collaboration with 2.3 fb$^{-1}$ of data. We measure a combined cross section of \SuperCombineXSall pb, which is the most precise measurement to date.Comment: 12 pages, 5 figure

b-Jet Identification in the D0 Experiment

Algorithms distinguishing jets originating from b quarks from other jet flavors are important tools in the physics program of the D0 experiment at the Fermilab Tevatron p-pbar collider. This article describes the methods that have been used to identify b-quark jets, exploiting in particular the long lifetimes of b-flavored hadrons, and the calibration of the performance of these algorithms based on collider data.Comment: submitted to Nuclear Instruments and Methods in Physics Research