Thermoacoustic refrigeration

A new refrigerator which uses resonant high amplitude sound in inert gases to pump heat is described and demonstrated. The phasing of the thermoacoustic cycle is provided by thermal conduction. This 'natural' phasing allows the entire refrigerator to operate with only one moving part (the loudspeaker diaphragm). The thermoacoustic refrigerator has no sliding seals, requires no lubrication, uses only low-tolerance machine parts, and contains no expensive components. Because the compressor moving mass is typically small and the oscillation frequency is high, the small amount of vibration is very easily isolated. This low vibration and lack of sliding seals makes thermoacoustic refrigeration an excellent candidate for food refrigeration and commercial/residential air conditioning applications. The design, fabrication, and performance of the first practical, autonomous thermoacoustic refrigerator, which will be flown on the Space Shuttle (STS-42), are described, and designs for terrestrial applications are presented

Perlodidae (Plecoptera) of Wisconsin

The family Perlodidae is one of the most abundant and widespread in the order Plecoptera. These stoneflies occur in a wide variety of clean-water habitats and as indicator organisms have potential for assessing water quality. Studies of this family in Wisconsin prior to 1965 were limited to occasional collections reported by Needham and Claassen (1925) and Frison (1935, 1937, 1942). In 1965 and 1966 a survey of the Wisconsin River and its tributaries yielded nymphs of 11 species of Isoperla (W. Hisenhoff, unpublished report), and later, nymphs and adults of 9 species were found in the Pine-Popple River (Hilsenhoff and Narf 1972). Between 1966 and 1971 additional Perlodidae were collected throughout the state by several persons, many of them by Arvin Krueger while surveying the mayfly fauna of Wisconsin (Krueger 1969)

Dynamic mode decomposition with control

We develop a new method which extends Dynamic Mode Decomposition (DMD) to incorporate the effect of control to extract low-order models from high-dimensional, complex systems. DMD finds spatial-temporal coherent modes, connects local-linear analysis to nonlinear operator theory, and provides an equation-free architecture which is compatible with compressive sensing. In actuated systems, DMD is incapable of producing an input-output model; moreover, the dynamics and the modes will be corrupted by external forcing. Our new method, Dynamic Mode Decomposition with control (DMDc), capitalizes on all of the advantages of DMD and provides the additional innovation of being able to disambiguate between the underlying dynamics and the effects of actuation, resulting in accurate input-output models. The method is data-driven in that it does not require knowledge of the underlying governing equations, only snapshots of state and actuation data from historical, experimental, or black-box simulations. We demonstrate the method on high-dimensional dynamical systems, including a model with relevance to the analysis of infectious disease data with mass vaccination (actuation).Comment: 10 pages, 4 figure

Window Dressing in Reported Earnings

The article discusses the use of the term window dressing, a wide range of techniques for auditing, by audit clients to enhance the financial position of an entity through manipulated disclosures. The term refers to the reporting practices adopted by firms to distort earnings by changing the way stakeholders perceived the financial figures. A research suggests that firms must engage in the type of manipulative behavior for the purpose of economic incentives

Feeding Techniques To Increase Calf Growth In The First Two Months Of Life

End of project reportData from Cornell University and the University of Illinois in the USA suggested that average daily liveweight gains of 900 to 1000 g/calf/day could be achieved from birth to weaning provided the calf milk replacer (CMR) is formulated to meet the calf’s amino acid requirements for such a rate of gain. Their findings suggested a daily milk replacer DM allowance of 1250 to 1500 g/d with a crude protein content of 26 to 30%. A series of studies were undertaken, at ARINI with home born dairy calves and at Grange Beef Research Centre with purchased dairy calves, to determine the effect of increasing the daily milk replacer DM allowance and or increasing the crude protein content of the CMR on calf performance.The main outcomes of these studies were There was no growth or intake response in any of the studies to increasing the crude protein content of the CMP from 23% to 28%. Calf growth rates responded to increasing the dailymilk replacer allowance from 600 to 1200 g/day for both home bred and purchased calves. However, the effect was not significant post-weaning in any of the studies. In all of the studies (for both home reared and purchased calves) feeding a high level of CMRdecreased concentrate DM intake. However, the calves concentrate intakes were similar post-weaning. The home bred calves with free access to the milk replacer feeders failed to consume their 1200 g/day allowance. Calves offered 600 or 1200 g of CMR/day had average consumption of 554 and 944 g/d, respectively, in the milk feeding period. Feeding a high (1200 g/d) compared to a low level (600 g/d) CMRdiet for the first 56 days had no significant effect on carcass weight or carcass characteristics when purchased male calves were slaughtered off an ad libitum concentrate diet after 388 days. The final carcass weights were 231 and 240 kg for the respective 600 and 1200 g/d CMR. Reducing the fat content of the CMRfrom 18% to 12% did not have any effect on concentrate intake or liveweight gain