19,450 research outputs found
Study of nonstationary random process theory Final report, 1 Jul. 1966 - 30 Apr. 1967
Nonstationary random processes in nonreal-time applications - theories for nonreal-time correlation and spectrum analysi
Synthesis methods for manual aerospace control systems with applications to SST design
Synthesis methods for manual aerospace control systems using digital programming and man machine performance data with application to supersonic transport desig
Study of Nonstationary Random Process Theory
Nonstationary random process theor
An Evaluation of Herbicides for Broadleaf-Weed Control in Rapeseed: Efficacy, Phytotoxicity, and Soil Persistence Studies
At the recommended rates (1.0 lb/A for trifluralin, ethalfluralin, EL5261; 0.75 lb/A for dinitramine; 1.2 lb/A for nitrofen), none of the herbicides we evaluated in these studies reduced rapeseed stands, yields, or test weights. However, at higher rates (1. 5, 3.0 lb A), dinitramine reduced rapeseed stands, but this did not result in decreased yields. None of the other herbicides reduced rapeseed stand, yield, or test weights when applied at up to four times the recommended rate. No trifluralin residues were detected in rapeseed whole-plant or seed samples. All of the herbicides provided adequate control of common lambsquarters (Chenopodium album L.). Corn spurry (Spergula arvensis L.) was controlled by trifluralin. ethalfluralin. EL-5261, and nitrofen. All of the herbicides except nitrofen controlled chickweed [Stellaria media (L.) Cyrillo].
In 1979, 51 per cent of the trifluralin applied remained at the end of the growing season in one study while 26 per cent remained in another study. The rate of degradation at three sites in 1979 were as follows (greatest to least); Delta Junction, Matanuska Valley, Fairbanks. Degradation rates of trifluralin were not significantly different in three soil types or at two different application rates. Trifluralin showed no signs of leaching through the soil profile. In 1981, 25 per cent of the trifluralin, 8 per cent of the ethalfluralin, and 24 per cent of the EL-5261 applied remained at the end of the growing season. Despite the relatively long persistence of these preplant, incorporated herbicides, yields and test weights of barley planted in succeeding years were not reduced. A benefit of these persistent residues was control of broadleaf weeds in the succeeding barley crop
The Distribution of \u3ci\u3eCorydalus Cornutus\u3c/i\u3e (Linnaeus) and \u3ci\u3eNigronia Serricornis (Say) (Megaloptera: Corydalidae) in Michigan
(excerpt)
The distribution of the hellgrammite [Corydalus cornutus (Linnaeus)] and the sawcombed fishfly [Nigronia serricornis (Say)] in Michigan was determined as part of an investigation of the biology of these large Megalopterans (Knight and Simmons, 1975a, 1975b). Megalopteran larvae are some of the largest aquatic insects, with a maximum length of approximately 84 mm. They are robust larvae with paired lateral abdominal appendages on segments 1-8 and a pair of anal prolegs bearing two strong hooks. They are fiercely predaceous and generally insectivorous, feeding chiefly on larvae of Simulium, Cheumatopsyche, Hydropsyche and Chironomidae, but eating almost anything they can subdue, including their own kind (Chandler, 1956; Stewart et al., 1973)
Span Load Distribution on Two Monoplanes Wing Models as Affected by Twist and Sweepback
The results presented in this note show the effect of twist and sweepback on the span load distribution over two monoplane wing models. The tests were made in the Atmospheric Wind Tunnel of the Langley Memorial Aeronautical Laboratory. The data are taken from the results of an investigation dealing primarily with lateral stability. As presented, they are suitable as an aid in the structural design of certain monoplane wings
Performance of Agronomic Crop Varieties in Alaska 1978 –2002
There is no such thing as the perfect variety for Alaska. Some varieties are adapted to a wide range of climatic and geographic locations, while others are more specific in their adaptation. The change in elevation of a few hundred feet or a move of a few miles can have a considerable effect on the performance of any variety. Also, cultural practices such as tillage, fertilizer rates, planting date, seeding rate, pest control, and a multitude of other factors can also influence crop yields. This is especially noticeable in northern environments such as Alaska. For example, date-of-planting studies done by F.J. Wooding (1973) and C.W. Knight (1989) found that any date after the middle of May for planting an agronomic crop can result in delayed maturity, low yields, and low quality grain, even for the best adapted varieties for Alaska
Wind Tunnel Pressure Distribution Tests on a Series of Biplane Wing Models. Part III Effects of Charges in Various Combinations of Stagger, Gap, Sweepback, and Decalage
This preliminary report furnishes information on the changes in the forces on each wing of a biplane cellule for various combinations of stagger and gap, stagger and sweepback, stagger and decalage, and gap and decalage. The data were obtained from pressure distribution tests made in the atmospheric wind tunnel of the Langley Memorial Aeronautical Laboratory. Since each test was carried up to 90deg angle of attack, the results may be used in the study of stalled flight and of spinning as well as in the structural design of biplane wings
Correlation of spray dropsize distribution and injector variables Interim report
Correlation of spray drop size distribution and injector variable
On the metrizability of spaces with a sharp base
A base for a space is said to be sharp if, whenever and is a sequence of pairwise distinct elements of
each containing , the collection is a local base at . We answer questions raised by
Alleche et al. and Arhangelski\u{\i} et al. by showing that a pseudocompact
Tychonoff space with a sharp base need not be metrizable and that the product
of a space with a sharp base and need not have a sharp base. We prove
various metrization theorems and provide a characterization along the lines of
Ponomarev's for point countable bases.Comment: 10 pages. Reprinted from Topology and its Applications, in press,
Chris Good, Robin W. Knight and Abdul M. Mohamad, On the metrizability of
spaces with a sharp bas
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