115,180 research outputs found
Voltinism and Laboratory Rearing of \u3ci\u3eMicrovelia Hinei\u3c/i\u3e (Heteroptera: Gerromorpha: Veliidae)
Voltinism in Microvelia hinei was studied in southern Illinois during 1989 and 1990. This species apparently overwintered as adults, which became active in late April; adults were last collected in late September. First instars were found from mid-May to late June, second instars from early-May to late October, third instars from mid-May to mid-July, fourth instars from mid-May to mid-August, and fifth instars from mid-May to mid-August. The sequences of peaks of nymphal instars and adults indicate that this species is at least bivoltine in southern Illinois. This species was reared from egg to adult at 26.7 ± 0.6°C and under a 14L:10D photoperiod. The incubation period averaged 6.41 days; and the five nymphal stadia, 4.28, 2.76, 2.52, 3.00, and 4.08 days, respectively. Total developmental time averaged 25.00 days
State Records and Confirmations of Arkansas Flat Bugs (Heteroptera: Aradidae)
Eight aradid species are reported for the first time from Arkansas including Aneurus pygmaeus, Aradus cincticornis, Aradus crenatus, Quilnus niger, Mezira granulata, Mezira lobata, Mezira sayi, and Neuroctenus simplex. The presence of Aradus acufus, Aradus falleni, and Aradus robustus in Arkansas is confirmed
Novel convolution-based signal processing techniques for an artificial olfactory mucosa
As our understanding of the human olfactory system has grown, so has our ability to design artificial devices that mimic its functionality, so called electronic noses (e-noses). This has led to the development of a more sophisticated biomimetic system known as an artificial olfactory mucosa (e-mucosa) that comprises a large distributed sensor array and artificial mucous layer. In order to exploit fully this new architecture, new approaches are required to analyzing the rich data sets that it generates. In this paper, we propose a novel convolution based approach to processing signals from the e-mucosa. Computer simulations are performed to investigate the robustness of this approach when subjected to different real-world problems, such as sensor drift and noise. Our results demonstrate a promising ability to classify odors from poor sensor signals
Distinguishing Nymphal Instars of \u3ci\u3eMesovelia Mulsanti\u3c/i\u3e (Heteroptera: Mesoveliidae)
The five nymphal instars of Mesouelia mulsanti can be separated by the number of rows of setae on the second abdominal tergum. Fifth instars can be separated from younger instars and from each other by the degree of development of the external genitalia
Random fields of multivariate test statistics, with applications to shape analysis
Our data are random fields of multivariate Gaussian observations, and we fit
a multivariate linear model with common design matrix at each point. We are
interested in detecting those points where some of the coefficients are nonzero
using classical multivariate statistics evaluated at each point. The problem is
to find the -value of the maximum of such a random field of test statistics.
We approximate this by the expected Euler characteristic of the excursion set.
Our main result is a very simple method for calculating this, which not only
gives us the previous result of Cao and Worsley [Ann. Statist. 27 (1999)
925--942] for Hotelling's , but also random fields of Roy's maximum root,
maximum canonical correlations [Ann. Appl. Probab. 9 (1999) 1021--1057],
multilinear forms [Ann. Statist. 29 (2001) 328--371], [Statist.
Probab. Lett 32 (1997) 367--376, Ann. Statist. 25 (1997) 2368--2387] and
scale space [Adv. in Appl. Probab. 33 (2001) 773--793]. The trick
involves approaching the problem from the point of view of Roy's
union-intersection principle. The results are applied to a problem in shape
analysis where we look for brain damage due to nonmissile trauma.Comment: Published in the Annals of Statistics (http://www.imstat.org/aos/) by
the Institute of Mathematical Statistics (http://www.imstat.org
Comparison of Two Population Sampling Methods Used in Field Life History Studies of \u3ci\u3eMesovelia Mulsanti\u3c/i\u3e (Heteroptera: Gerromorpha: Mesoveliidae) in Southern Illinois
A field life history study of Mesovelia mulsanti was conducted in southÂern Illinois, the results of which are compared with those from an earlier study also conducted in southern Illinois. The two studies differed in the collecting techniques used (quadrat sampler versus aquatic net). Results of the present study give a clearer picture of the life history of this insect be cause the quadrat sampler collected representative samples of nymphs and adults more effectively than the aquatic net and, thus, the quadrat samples more accurately represented the actual chronology of the annual generations
A comparison of CMB- and HLA-based approaches to type I interoperability reference model problems for COTS-based distributed simulation
Commercial-off-the-shelf (COTS) simulation packages (CSPs) are software used by many simulation modellers to build and experiment with models of various systems in domains such as manufacturing, health, logistics and commerce. COTS distributed simulation deals with the interoperation of CSPs and their models. Such interoperability has been classified into six interoperability reference models. As part of an on-going standardisation effort, this paper introduces the COTS Simulation Package Emulator, a proposed benchmark that can be used to investigate Type I interoperability problems in COTS distributed simulation. To demonstrate its use, two approaches to this form of interoperability are discussed, an implementation of the CMB conservative algorithm, an example of a so-called “light” approach, and an implementation of the HLA TAR algorithm, an example of a so-called “heavy” approach. Results from experimentation over four federation topologies are presented and it is shown the HLA approach out performs the CMB approach in almost all cases. The paper concludes that the CSPE benchmark is a valid basis from which the most efficient approach to Type I interoperability problems for COTS distributed simulation can be discovered
The Clumpiness of Cold Dark Matter: Implications for the Annihilation Signal
We examine the expected signal from annihilation events in realistic cold
dark matter halos. If the WIMP is a neutralino, with an annihilation
cross-section predicted in minimal SUSY models for the lightest stable relic
particle, the central cusps and dense substructure seen in simulated halos may
produce a substantial flux of energetic gamma rays. We derive expressions for
the relative flux from such events in simple halos with various density
profiles, and use these to calculate the relative flux produced within a large
volume as a function of redshift. This flux peaks when the first halos
collapse, but then declines as small halos merge into larger systems of lower
density. Simulations show that halos contain a substantial amount of dense
substructure, left over from the incomplete disruption of smaller halos as they
merge together. We calculate the contribution to the flux due to this
substructure, and show that it can increase the annihilation signal
substantially. Overall, the present-day flux from annihilation events may be an
order of magnitude larger than predicted by previous calculations. We discuss
the implications of these results for current and future gamma-ray experiments.Comment: 8 pages, 6 figures; submitted to MNRA
L-band, 1.2 m parabolic antenna-noise temperature measurement
Extensive antenna-noise temperature measurements at 1.6 GHz (L-band) were made using a 1.2 m (4 ft. diameter) parabolic dish antenna mounted on the flying bridge of a modern 15,690-ton, commercial-container ship. Both in-harbor and at-sea radiometer measurements were made that indicated a steady background, antenna-noise temperature value slightly less than 70 degrees Kelvin (K) at elevation angles of 5 percent, and greater, at 1.6 GHz. A comparison of theoretical and measured values indicate excellent agreement within about 5K for at-sea data. These measurements are helpful to RF equipment designers of maritime, L-band shipboard terminals for operation with the two, geostationary, maritime satellites, Marisat-A and -B
Using a desktop grid to support simulation modelling
Simulation is characterized by the need to run multiple sets of computationally intensive experiments. We argue that Grid computing can reduce the overall execution time of such experiments by tapping into the typically underutilized network of departmental desktop PCs, collectively known as desktop grids. Commercial-off-the-shelf simulation packages (CSPs) are used in industry to simulate models. To investigate if Grid computing can benefit simulation, this paper introduces our desktop grid, WinGrid, and discusses how this can be used to support the processing needs of CSPs. Results indicate a linear speed up and that Grid computing does indeed hold promise for simulation
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