New approaches to renewable energy education

The rapid expansion of the renewable energy industry is producing a huge demand for welltrained professional people to design, install and maintain new systems. There is also a substantial need for policy analysts, researchers and teachers with experience in renewables. Many professional people are now seeking to move their career paths into the renewable energy field and they require advanced, on-the-job training. It is no longer sufficient to add a few topics or units on renewables to a conventional science or engineering course. Renewable energy education is emerging as a new discipline in its own right, with its own interdisciplinary curriculum that meets the criteria for sustainable development. Educating the community is also vital for creating a greater awareness of, and confidence in, renewable energy systems, and for training people to use them properly. This paper describes some new approaches to renewable energy education that seek to meet the needs of industry and society for high-quality, environmentally friendly and socially responsible energy supply systems

Multivortex Solutions of the Weierstrass Representation

The connection between the complex Sine and Sinh-Gordon equations on the complex plane associated with a Weierstrass type system and the possibility of construction of several classes of multivortex solutions is discussed in detail. We perform the Painlev\'e test and analyse the possibility of deriving the B\"acklund transformation from the singularity analysis of the complex Sine-Gordon equation. We make use of the analysis using the known relations for the Painlev\'{e} equations to construct explicit formulae in terms of the Umemura polynomials which are $\tau$-functions for rational solutions of the third Painlev\'{e} equation. New classes of multivortex solutions of a Weierstrass system are obtained through the use of this proposed procedure. Some physical applications are mentioned in the area of the vortex Higgs model when the complex Sine-Gordon equation is reduced to coupled Riccati equations.Comment: 27 pages LaTeX2e, 1 encapsulated Postscript figur

Photon number discrimination without a photon counter and its application to reconstructing non-Gaussian states

The non-linearity of a conditional photon-counting measurement can be used to `de-Gaussify' a Gaussian state of light. Here we present and experimentally demonstrate a technique for photon number resolution using only homodyne detection. We then apply this technique to inform a conditional measurement; unambiguously reconstructing the statistics of the non-Gaussian one and two photon subtracted squeezed vacuum states. Although our photon number measurement relies on ensemble averages and cannot be used to prepare non-Gaussian states of light, its high efficiency, photon number resolving capabilities, and compatibility with the telecommunications band make it suitable for quantum information tasks relying on the outcomes of mean values.Comment: 4 pages, 3 figures. Theory section expanded in response to referee comment

A 1200 Year Record of Hydrologic Variability in the Sierra Nevada from Sediments in Walker Lake, Nevada

Measurements of the oxygen isotopic composition (δ18O) of the total inorganic carbon (TIC) fraction from cored sediments of Walker Lake, Nevada, were conducted at an average resolution of ∼3 years per sample over the last 1200 years. On the basis of radiocarbon analysis on the total organic carbon (TOC) fraction, a δ18O time series was created to reconstruct changes in hydrologic conditions back to AD 800. The timings of variations in the TIC δ18O record are generally consistent with the tree ring-based Sacramento River flow record spanning AD 869 to 1977, indicating that Walker Lake δ18O contains information about past changes in at least regional hydrologic conditions. Comparison with the δ18O record from Pyramid Lake sediments indicates that both basins have recorded five century-scale oscillations in regional hydrologic conditions since AD 800. Several of these changes in hydrologic conditions appear synchronous with century-scale California Current water temperature changes derived from analysis of sediment cores from the Santa Barbara Basin also attesting to the regional extent of these climatic fluctuations. Nearly synchronous oscillations in the Sierra wetness and the California Current suggest that regional changes in atmospheric circulation may have played an important role in century-scale climate variability over the last millennium

Late Holocene Lake-Level Fluctuations in Walker Lake, Nevada, USA

alker Lake, a hydrologically closed, saline, and alkaline lake, is situated along the western margin of the Great Basin in Nevada of the western United States. Analyses of the magnetic susceptibility (χ), total inorganic carbon (TIC), and oxygen isotopic composition (δ18O) of carbonate sediments including ostracode shells (Limnocythere ceriotuberosa) from Walker Lake allow us to extend the sediment record of lake-level fluctuations back to 2700 years B.P. There are approximately five major stages over the course of the late Holocene hydrologic evolution in Walker Lake: an early lowstand (\u3e 2400 years B.P.), a lake-filling period (∼ 2400 to ∼ 1000 years B.P.), a lake-level lowering period during the Medieval Warm Period (MWP) (∼ 1000 to ∼ 600 years B.P.), a relatively wet period (∼ 600 to ∼ 100 years B.P.), and the anthropogenically induced lake-level lowering period (\u3c 100 years B.P.). The most pronounced lowstand of Walker Lake occurred at ∼ 2400 years B.P., as indicated by the relatively high values of δ18O. This is generally in agreement with the previous lower resolution paleoclimate results from Walker Lake, but contrasts with the sediment records from adjacent Pyramid Lake and Siesta Lake. The pronounced lowstand suggests that the Walker River that fills Walker Lake may have partially diverted into the Carson Sink through the Adrian paleochannel between 2700 to 1400 years B.P

Effects of chicory roots on finishing performance and CLA and fatty acid composition in longissimus muscle of Friesian steers

Low profitability is believed to be the greatest hindrance profitability is believed to be the greatest hindrance for a more extensive use of dairy breed bull calves in for a more extensive use of dairy breed bull calves in organic beef production systems organic beef production systems Among certain consumers, there is an increasing interest Among certain consumers, there is an increasing interest for organic beef production for organic beef production However, there is a need for reliable information about However, there is a need for reliable information about and documentation for production parameters, methods and documentation for production parameters, methods for rearing and housing, feeding strategies etc. to be able for rearing and housing, feeding strategies etc. to be able to increase the consumption of beef meat based on dairy to increase the consumption of beef meat based on dairy calves in Denmark calves in Denmark. Specifically, we believe there will be increased focus on Specifically, we believe there will be increased focus on improving animal health and welfare and product quality in improving animal health and welfare and product quality in the steer production systems the steer production systems There will also be a wish from the society and EU to use There will also be a wish from the society and EU to use and preserve the biodiversity of the marginal grazing and preserve the biodiversity of the marginal grazing areas areas The project reported here arises from a larger project The project reported here arises from a larger project investigating the effects of grazing system (set investigating the effects of grazing system (set stocking vs. two stocking vs. two-paddock rotation) for steers and the paddock rotation) for steers and the use of bioactive crops (especially chicory) use of bioactive crops (especially chicory). Chicory is used because of the possible positive Chicory is used because of the possible positive influence on animal health, i.e., parasite control, meat influence on animal health, i.e., parasite control, meat quality and sensory quality of meat from both steers quality and sensory quality of meat from both steers and pigs (including CLA content, selenium and and pigs (including CLA content, selenium and antioxidative antioxidative status, drip loss and boar status, drip loss and boar taint/ taint/androstenone androstenone levels) levels). The overall objective of the entire project was to The overall objective of the entire project was to develop production methods/strategies that could develop production methods/strategies that could improve the quality aspects of organic meat improve the quality aspects of organic meat

Compressive strength of interbody cages in the lumbar spine: the effect of cage shape, posterior instrumentation and bone density

One goal of interbody fusion is to increase the height of the degenerated disc space. Interbody cages in particular have been promoted with the claim that they can maintain the disc space better than other methods. There are many factors that can affect the disc height maintenance, including graft or cage design, the quality of the surrounding bone and the presence of supplementary posterior fixation. The present study is an in vitro biomechanical investigation of the compressive behaviour of three different interbody cage designs in a human cadaveric model. The effect of bone density and posterior instrumentation were assessed. Thirty-six lumbar functional spinal units were instrumented with one of three interbody cages: (1) a porous titanium implant with endplate fit (Stratec), (2) a porous, rectangular carbon-fibre implant (Brantigan) and (3) a porous, cylindrical threaded implant (Ray). Posterior instrumentation (USS) was applied to half of the specimens. All specimens were subjected to axial compression displacement until failure. Correlations between both the failure load and the load at 3 mm displacement with the bone density measurements were observed. Neither the cage design nor the presence of posterior instrumentation had a significant effect on the failure load. The loads at 3 mm were slightly less for the Stratec cage, implying lower axial stiffness, but were not different with posterior instrumentation. The large range of observed failure loads overlaps the potential in vivo compressive loads, implying that failure of the bone-implant interface may occur clinically. Preoperative measurements of bone density may be an effective tool to predict settling around interbody cages

Scattering of first and second sound waves by quantum vorticity in superfluid Helium

We study the scattering of first and second sound waves by quantum vorticity in superfluid Helium using two-fluid hydrodynamics. The vorticity of the superfluid component and the sound interact because of the nonlinear character of these equations. Explicit expressions for the scattered pressure and temperature are worked out in a first Born approximation, and care is exercised in delimiting the range of validity of the assumptions needed for this approximation to hold. An incident second sound wave will partly convert into first sound, and an incident first sound wave will partly convert into second sound. General considerations show that most incident first sound converts into second sound, but not the other way around. These considerations are validated using a vortex dipole as an explicitely worked out example.Comment: 24 pages, Latex, to appear in Journal of Low Temperature Physic