11,441 research outputs found
\u3ci\u3ePolistes Dominulus\u3c/i\u3e (Hymenoptera: Vespidae) Found in Michigan
(excerpt)
On 25 May 1995, a single foundress colony of Polistes dominulus (Christ) was discovered on a study site at Oakland University in Rochester, Michigan (Oakland County). This is the first record of Polistes dominulus in the state of Michigan
Historical Calibration of a Water Account System
Models that are used for future based scenarios should be calibrated with historical water supply and use data. Historical water records in Australia are discontinuous, incomplete and often incongruently disaggregated. We present a systematic method to produce a coherent reconstruction of the historical provision and consumption of water in Victorian catchments. This is demonstrated using WAS: an accounting and simulation tool that tracks the stocks and flows of physical quantities relating to the water system. The WAS is also part of, and informed by, an integrated framework of stocks and flows calculators for simulating long-term interactions between other sectors of the physical economy. Both the WAS and related frameworks consider a wide scope of inputs regarding population, land use, energy and water. The physical history of the water sector is reconstructed by integrating water data with these information sources using a data modelling process that resolves conflicts and deduces missing information. The WAS allows strategic exploration of water and energy implications of scenarios of water sourcing, treatment, delivery and end use cognisant of historical records.water accounting, stocks and flows, historical time series, data modelling, calibration
Looptop Hard X-Ray Emission in Solar Flares: Images and Statistics
The discovery of hard X-ray sources near the top of a flaring loop by the HXT
instrument on board the YOHKOH satellite represents a significant progress
towards the understanding of the basic processes driving solar flares. In this
paper we extend the previous study of limb flares by Masuda (1994) by including
all YOHKOH observations up through August 1998. We report that from October
1991 to August 1998, YOHKOH observed 20 X-ray bright limb flares (where we use
the same selection criteria as Masuda), of which we have sufficient data to
analyze 18 events, including 8 previously unanalyzed flares. Of these 18
events, 15 show detectable impulsive looptop emission. Considering that the
finite dynamic range (about a decade) of the detection introduces a strong bias
against observing comparatively weak looptop sources, we conclude that looptop
emission is a common feature of all flares. We summarize the observations of
the footpoint to looptop flux ratio and the spectral indices. We present light
curves and images of all the important newly analyzed limb flares. Whenever
possible we present results for individual pulses in multipeak flares and for
different loops for multiloop flares. We then discuss the statistics of the
fluxes and spectral indices of the looptop and footpoint sources taking into
account observational selection biases. The importance of these observations
(and those expected from the scheduled HESSI satellite with its superior
angular spectral and temporal resolution) in constraining acceleration models
and parameters is discussed briefly.Comment: 27 pages (13 embedded figures). Accepted for publication in Ap
Extrinsic germanium Blocked Impurity Bank (BIB) detectors
Ge:Ga blocked-impurity-band (BIB) detectors with long wavelength thresholds greater than 190 microns and peak quantum efficiencies of 4 percent, at an operating temperature of 1.8 K, have been fabricated. These proof of concept devices consist of a high purity germanium blocking layer epitaxially grown on a Ga-doped Ge substrate. This demonstration of BIB behavior in germanium enables the development of far infrared detector arrays similar to the current silicon-based devices. Present efforts are focussed on improving the chemical vapor deposition process used to create the blocking layer and on the lithographic processing required to produce monolithic detector arrays in germanium. Approaches to test the impurity levels in both the blocking and active layers are considered
Final Report On A Cold Climate Permeable Interlocking Concrete Pavement Test Facility At The University Of New Hampshire Stormwater Center
The Effect of Resistivity on the Nonlinear Stage of the Magnetorotational Instability in Accretion Disks
We present three-dimensional magnetohydrodynamic simulations of the nonlinear
evolution of the magnetorotational instability (MRI) with a non-zero Ohmic
resistivity. The properties of the saturated state depend on the initial
magnetic field configuration. In simulations with an initial uniform vertical
field, the MRI is able to support angular momentum transport even for large
resistivities through the quasi-periodic generation of axisymmetric radial
channel solutions rather than through the maintenance of anisotropic
turbulence. Simulations with zero net flux show that the angular momentum
transport and the amplitude of magnetic energy after saturation are
significantly reduced by finite resistivity, even at levels where the linear
modes are only slightly affected. This occurs at magnetic Reynolds numbers
expected in low, cool states of dwarf novae, these results suggest that finite
resistivity may account for the low and high angular momentum transport rates
inferred for these systems.Comment: 8 figures, accepted for publication in Ap
Competition in public service provision: the role of not-for-profit providers
With public services such as health and education, it is not straightforward for consumers to assess the quality of provision. Many such services are provided by monopoly not-for-profit providers and there is concern that for-profit providers may increase profit at the expense of quality. This paper explores the implications of entry by for-profit providers when there is unobserved quality. The model generates three key policy-relevant insights. First, by developing a novel approach to competition between different organizational forms, it frames the relevant trade-offs precisely. Second, it shows the value of keeping an incumbent not-for-profit as an active provider. Third, it characterizes the optimal payment (or voucher value) to an entrant for each consumer who switches in a way that can be applied empirically
The Panchromatic Starburst Intensity Limit At Low And High Redshift
The integrated bolometric effective surface brightness S_e distributions of
starbursts are investigated for samples observed in 1. the rest frame
ultraviolet (UV), 2. the far-infrared and H-alpha, and 3. 21cm radio continuum
emission. For the UV sample we exploit a tight empirical relationship between
UV reddening and extinction to recover the bolometric flux. Parameterizing the
S_e upper limit by the 90th percentile of the distribution, we find a mean
S_{e,90} = 2.0e11 L_{sun}/kpc^2 for the three samples, with a factor of three
difference between the samples. This is consistent with what is expected from
the calibration uncertainties alone. We find little variation in S_{e,90} with
effective radii for R_e ~ 0.1 - 10 kpc, and little evolution out to redshifts z
~ 3. The lack of a strong dependence of S_{e,90} on wavelength, and its
consistency with the pressure measured in strong galactic winds, argue that it
corresponds to a global star formation intensity limit (\dot\Sigma_{e,90} ~ 45
M_{sun}/kpc^2/yr) rather than being an opacity effect. There are several
important implications of these results: 1. There is a robust physical
mechanism limiting starburst intensity. We note that starbursts have S_e
consistent with the expectations of gravitational instability models applied to
the solid body rotation portion of galaxies. 2. Elliptical galaxies and spiral
bulges can plausibly be built with maximum intensity bursts, while normal
spiral disks can not. 3. The UV extinction of high-z galaxies is significant,
implying that star formation in the early universe is moderately obscured.
After correcting for extinction, the observed metal production rate at z ~ 3
agrees well with independent estimates made for the epoch of elliptical galaxy
formation.Comment: 31 pages Latex (aas2pp4.sty,psfig.sty), 9 figures, accepted for
publication in the Astronomical Journa
MICROCOMPUTER BUDGET MANAGEMENT SYSTEM
The enterprise budget, whole farm cash flow, and income statement are fundamental tools of farm and ranch management. The "Microcomputer Budget Management System" (MBMS) is a microcomputer software package that facilitates the storage and use of information for crop and livestock budgeting. It performs the calculations for several enterprise budgeting formats and for preparation of whole farm resource use reports and financial statements. The MBMS also includes internal machinery and irrigation cost calculation routines. MBMS was developed for use by extension staff, researchers, lenders, consultants, and operators of diversified farms and ranches with many enterprises that use enterprise and whole farm budgeting for analysis and planning activities. The flexibility and detailed nature of the program requires the user to have knowledge of enterprise budgeting and operation of complex computer programs. This paper presents a discussion of the features and capabilities of the software and the computational procedures used in the cost calculations.Research and Development/Tech Change/Emerging Technologies,
Barriers to innovation and knowledge generation: The challenges of conducting business and social research in an emerging country context
© 2018 Journal of Innovation & Knowledge The Middle East, as a region, contributes proportionally less to new knowledge generation than other parts of the world. The United Arab Emirates (UAE) has sought to correct this imbalance through efforts to promote a knowledge-based economy and through educational investment. In light of these advances, significant challenges still remain in the promotion and production of high quality research in the social sciences, including business. The current monograph highlights the vital importance of such research to the social and economic development of the UAE. Reflecting on nearly a decade of conducting research in the UAE with varying degrees of success the authors highlight critical incidents, experiences and observations which serve to illustrate the challenges of new knowledge creation in the business and social sciences. Discussions focus on identifiable barriers to high quality research at both the micro and macro levels, within and outside the UAE, with specific recommendations on how such barriers can be overcome
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