2,639 research outputs found
Modes in Algol Y
It recently appeared to the author that the semantics of recursively
defined data-types (from now on the term circularly defined data-types
will be used to keep away from the "recursive function theory" connotation
of the adjective "recursive") could benefit largely from the bulk of
recent work on domain equations initiated by Dana Scott
Investigating the rheological properties and compatibility behaviours of RET/PE and WR/CR/ SBS compound-modified bitumen
Two types of elastomer/plastic compound-modified bitumen were developed by means of incorporating the reactive elastomeric terpolymer (RET) into the plastic (high-density polyethylene HDPE or recycled polyethylene RPE) modified bitumen and adding the wax residue (WR) into the bitumen/elastomer (crumb rubber CR or styrene–butadiene–styrene SBS) blends. The rheological properties, morphology microstructure and storage stability of these novel elastomer/plastic compound-modified binders were characterised. The results revealed that RET elastomer positively improved the high-temperature modulus, temperature insensitivity, rut resistant, elastic recovery and shear-resistance of HDPE- and RPE-modified bitumen. However, excessive RET dosage adversely influenced the cracking resistance of plastic-modified bitumen, and its optimum dosage was recommended as 1 wt%. Moreover, RET elastomer significantly strengthened the storage stability of HDPE and RPE-modified binders. The elasticity improvement effect of RET was attributed to the generated polymer network. On the other hand, adding WR limitedly deteriorated the rutting resistance and weakened the elastic recovery performance of elastomer (CR and SBS) modified bitumen. To ensure the low-temperature performance, the optimum level of WR was 2 wt%. Furthermore, the addition of WR promoted the compatibility and dispersion of CR and SBS modifiers in bitumen.Pavement Engineerin
An analysis of the relative weight (Wr) of yellow perch from Indiana waters of Lake Michigan, 1984-91
Relative weight (Wr) of yellow perch (Perca flavescens) was evaluated for fish collected from the Indiana waters of Lake Michigan in June, July and August of 1976 and 1984-1991. Computation of Wr was completed for individual fish in 20 mm intervals over the size range from 100-219 mm using Wr = (W/Ws) 100 where W=weight of a fish in grams and Ws=standard weight for a fish of the same length. Length was highly correlated with weight in all years for males, females and sexes combined (r=0.97-0.99). Distributions of predicted weights for fish at 130 mm and 250 mm were at or near modes of the populations used to construct the Ws equation for yellow perch. Relative weights consistently decreased with increasing size in all years for males, females and sexes combined. Using 1976 length-weight data when the yellow perch population was sparse and fast growing as a standard (100%) for comparison, relative condition factors (Q) increased with increasing size in some years and decreased with increasing size in others for males females and sexes combined and it did not appear to be length dependent. When comparing Wr at 100 mm and 200 mm by sex and month, f hales had higher Wr than males at 100 mm in seven of nine years in June, six of nine years in July and only four of nine years in August. Female fish also had higher Wr than males at 200 mm in eight of nine years in June and July and six of nine years in August. There appeared to be no consistent pattern or trend of Wr increasing or decreasing by month for males, females or sexes combined. When Kn was evaluated for 100 mm and 200 mm fish by sex and year, male fish had higher Kn than females at 100 mm in all eight years. Male and female fish at 200 mm were more similar; male fish had higher Kn in three years, lower Kn in three years and equal Kn in two years. No relationships were found at 200 mm comparing Wr or Kn and CPE (quality/ h) for males (r=0.43; r=0.42), females (r=0.12; r=0.13) or sexes combined (r=0.28; r=0.22). Simple linear correlations of proportional stock density (PSD) with Wr and Kn revealed relative weights increased with PSD for 100 mm (r=0.51) and 200 mm (r=0.72) fish. Relative condition factors also increased with PSD for 100 mm fish, however the relationship was weak (r=0.30) but a strong correlation was found between Kn and PSD (r=0.81) for 200 mm fish. Based on these results, it appears that either Kn or Wr may be used inassessing the condition of yellow perch from the Indiana waters of Lake Michigan.Thesis (M.S.)Department of Biolog
WR 280 Practicum Report: Wildlife Management Techniques
Wildland RecreationAs part of the Wildland Recreation Spring Practicum, the author worked at the Fort St. John Fish and Wildlife Branch of the Ministry of Environment and Parks for two weeks, under the supervision of Rob Woods, Habitat Protection Technician. The author's volunteer work gave him an understanding of wildlife management techniques that included radio telemetry, classified counts, and ungulate aging/Harvest Cards
Neutrino jets from high-mass WR gauge bosons in TeV-scale left-right symmetric models
We reexamine the discovery potential at hadron colliders of high-mass right-handed (RH) gauge bosons WR—an inherent ingredient of left-right symmetric models (LRSM).We focus on the regime where theWR is very heavy compared to the heavy Majorana neutrino N, and we investigate an alternative signature for WR → N decays. The produced neutrinos are highly boosted in this mass regime. Subsequently, their decays via off-shell WR bosons to jets, i.e., N → ljj, are highly collimated, forming a single neutrino jet ðjNÞ. The final-state collider signature is then ljN, instead of the widely studied lljj. Present search strategies are not sensitive to this hierarchical mass regime due to the breakdown of the collider signature definition. We take into account QCD corrections beyond next-to-leading order (NLO) that are important for high-mass Drell-Yan processes at the 13 TeV Large Hadron Collider (LHC). For the first time, we evaluate WR production at NLO with threshold resummation at next-to-next-to-leading logarithm (NNLL) matched to the threshold-improved parton distributions. With these improvements, we find that a WR of mass MWR ¼ 3ð4Þ½5 TeV and mass ratio of ðmN=MWR Þ < 0.1 can be discovered with a 5–6σ statistical significance at 13 TeVafter 10ð100Þ½2000 fb−1 of data. Extending the analysis to the hypothetical 100 TeV Very Large Hadron Collider (VLHC), 5σ can be obtained for WR masses up to MWR ¼ 15ð30Þ with approximately 100 fb−1 (10 ab−1). Conversely, with 0.9ð10Þ½150 fb−1 of 13 TeV data, MWR <3ð4Þ½5 TeV and ðmN=MWR Þ < 0.1 can be excluded at 95% C.L.; with 100 fb−1 (2.5 ab−1) of 100 TeV data, MWR < 22ð33Þ TeV can be excluded
Vrist - brist - rist : Development of old initial wr in Scandinavian, particularly Swedish, dialects
The Germanic initial sound combination wr (e.g. in *wrītan 'write') has not been preserved in any standard language. In the Scandinavian languages the development of this sound combination has resulted in five different initial sounds or sound combinations, namely rw, r, w, br and vr. The aim of this study is to describe the occurrence of these sound combinations, and to explain their age and origin. A limited number of words, mainly from Swedish dialects, has been investigated. The Swedish material has been assembled in a collection that has largely also been mapped, and so has a collection of Norwegian dialect material. The result shows that br is frequent in the Swedish dialects and that it also occurs in Trøndelagen and Østlandet in Norway, and on Jutland. R is widespread in Norway and occurs in Sweden in some words in Norrland, Dalarna, Värmland, Dalsland, Uppland and on the island of Gotland. Rw has been documented in Upper Dalarna, and w in the same area, as well as in the Kalix dialect in northernmost Sweden. The author demonstrates that the Norwegian loss of w might have started already in the 6th century in western Norway. The loss on Gotland is independent and can be demonstrated in Old Gutnish. The metathesis rw is found in Swedish and Norwegian 13-14th century sources from Uppland, Västmanland, Östergötland and southeastern Norway. The developments wr > r and wr > rw probably have their roots in a difference between the west Norwegian wr and the east Norwegian and Swedish war which is documented from PrimScand times. W is a secondary development of rw. The change wr > br can be dated by place-name material to the early 15th century. The change wr > vr appears to have taken place at approximately the same time. The author demonstrates that the result, wr > br or wr > yr, is apparently governed by certain phonetic factors. The failure of the Germanic wr to survive depends on the combination being phonetically complex. The risk that w would be lost was therefore considerable. However, differentiating forces worked for its retention. All developments emanating from wr, apparently disparate, can be seen as features of a larger process where a general linguistic tendency towards a weakening of sounds is confronted by conservative forces, with the above results as a consequence.Doktorsavhandling vid Uppsala universitet 1991</p
Profile of Scott Taylor, 20, of Westbrook, a free-lance wrestler in the World Wr
Profile of Scott Taylor, 20, of Westbrook, a free-lance wrestler in the World Wrestling Federation who would like to become a full-time professional. Related article
Dynamic Imprints of Colliding-wind Dust Formation from WR 140
Carbon-rich Wolf-Rayet (WR) binaries are a prominent source of carbonaceous dust that contribute to the dust budget of galaxies. The “textbook” example of an episodic dust-producing WR binary, WR 140 (HD 193793), provides us with an ideal laboratory for investigating the dust physics and kinematics in an extreme environment. This study is among the first to utilize two separate JWST observations, from Cycle 1 ERS (2022 July) and Cycle 2 (2023 September), to measure WR 140’s dust kinematics and confirm its morphology. To measure the proper motions and projected velocities of the dust shells, we performed a novel point-spread function (PSF) subtraction to reduce the effects of the bright diffraction spikes and carefully aligned the Cycle 2 to the Cycle 1 images. At 7.7 μm, through the bright feature common to 16 dust shells (C1), we find an average dust shell proper motion of 390 ± 29 mas yr−1, which equates to a projected velocity of 2714 ± 188 km s−1 at a distance of 1.64 kpc. Our measured speeds are constant across all visible shells and consistent with previously reported dust expansion velocities. Our observations not only prove that these dusty shells are astrophysical (i.e., not associated with any PSF artifact) and originate from WR 140, but also confirm the “clumpy” morphology of the dust shells, in which identifiable substructures within certain shells persist for at least 14 months from one cycle to the next. These results support the hypothesis that clumping in the wind collision region is required for dust production in WR binaries
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The orbit and stellar masses of the archetype colliding-wind binary WR 140
We present updated orbital elements for the Wolf-Rayet (WR) binary WR 140 (HD 193793; WC7pd + O5.5fc). The new orbital elements were derived using previously published measurements along with 160 new radial velocity measurements across the 2016 periastron passage of WR 140. Additionally, four new measurements of the orbital astrometry were collected with the CHARA Array. With these measurements, we derive stellar masses of and . We also include a discussion of the evolutionary history of this system from the Binary Population and Spectral Synthesis model grid to show that this WR star likely formed primarily through mass-loss in the stellar winds, with only a moderate amount of mass lost or transferred through binary interactions. © 2021 The Author(s) Published by Oxford University Press on behalf of Royal Astronomical Society.Immediate accessThis item from the UA Faculty Publications collection is made available by the University of Arizona with support from the University of Arizona Libraries. If you have questions, please contact us at [email protected]
Vrist - brist - rist [Elektronisk resurs] : Utvecklingen av gammalt uddljudande <em>wr</em> i nordiska, särskilt svenska, dialekter
The Germanic initial sound combination wr (e.g. in *wrītan 'write') has not been preserved in any standard language. In the Scandinavian languages the development of this sound combination has resulted in five different initial sounds or sound combinations, namely rw, r, w, br and vr.The aim of this study is to describe the occurrence of these sound combinations, and to explain their age and origin. A limited number of words, mainly from Swedish dialects, has been investigated. The Swedish material has been assembled in a collection that has largely also been mapped, and so has a collection of Norwegian dialect material.The result shows that br is frequent in the Swedish dialects and that it also occurs in Trøndelagen and Østlandet in Norway, and on Jutland. R is widespread in Norway and occurs in Sweden in some words in Norrland, Dalarna, Värmland, Dalsland, Uppland and on the island of Gotland. Rw has been documented in Upper Dalarna, and w in the same area, as well as in the Kalix dialect in northernmost Sweden.The author demonstrates that the Norwegian loss of w might have started already in the 6th century in western Norway. The loss on Gotland is independent and can be demonstrated in Old Gutnish. The metathesis rw is found in Swedish and Norwegian 13-14th century sources from Uppland, Västmanland, Östergötland and southeastern Norway. The developments wr > r and wr > rw probably have their roots in a difference between the west Norwegian wr and the east Norwegian and Swedish war which is documented from PrimScand times. W is a secondary development of rw. The change wr > br can be dated by place-name material to the early 15th century. The change wr > vr appears to have taken place at approximately the same time. The author demonstrates that the result, wr > br or wr > yr, is apparently governed by certain phonetic factors.The failure of the Germanic wr to survive depends on the combination being phonetically complex. The risk that w would be lost was therefore considerable. However, differentiating forces worked for its retention. All developments emanating from wr, apparently disparate, can be seen as features of a larger process where a general linguistic tendency towards a weakening of sounds is confronted by conservative forces, with the above results as a consequence.</p
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