VALUE OF NEW TECHNOLOGIES IN DAIRY FARMING: THE CASE OF ROBOTIC MILKING

The economic value of the innovation robotic milking systems (AMS) is examined for Swedish dairy operations. A mixed integer mathematical programming model, considering crops, calving distribution, seasonality and capacity constraints of the AMS system, is developed. The marginal value of increasing the capacity of the AMS unit is found to amount to 40-60% of the milk revenues per cow.Technology innovations, Dairy systems, Livestock Production/Industries, Q12,

Metodstudier vid mobiltelefonanvändning

Mobiltelefoner är något som nästan alla har tillgång till idag. Samtidigt ökar hela tiden användningsområdena på just mobiltelefoner. Nya modeller kommer ständigt och i takt med detta ökar även funktionaliteten av dem. Det är idag möjligt att utföra en rad andra saker än att endast ringa och skicka SMS med hjälp av sin mobiltelefon. Olika personer använder sina telefoner på olika sätt, olika mycket och till olika saker och detta har studerats på en mängd olika sätt. Att mobiltelefoner är just mobila innebär att de följer människor när de förflyttar sig och därför har även mobiltelefonanvändning på olika platser studerats. Olika metoder lämpar sig olika bra beroende på var användningen skall studeras. Den här uppsatsen syftar till att försöka få fram vilka metoder som lämpar sig för att studera mobiltelefonanvändning med hemmet som användningsmiljö. Med hjälp av litteraturstudier kom vi fram till vilka metoder som var relevanta att testa i hemmiljö och därefter har vi utfört dessa. Vi kom fram till att det inte fanns någon specifik metod som var bättre än någon annan men att resultatet blev mycket bättre om man kombinerade olika typer av metoder

Fire Behaviour of Upholstered Furniture - An Experimental Study

The first and largely experimental part of a research program on flammability characteristics of upholstered furniture has been completed with full-scale tests in an extensively instrumented burn-out room as main element. The results indicate that fire response parameters vary within a large range with choice of filling, interlining and fabric material. Selection of performance criteria may cause difficulties, as parameters like heat release and smoke potential fluctuate strongly during the fire process. A second part of the program will be directed towards measurement of heat release by oxygen consumption methods, more detailed smoke and gas analysis measurements and use of mathematical simulation procedures

Zinc recovery from Waste-to-Energy fly ash – A pilot test study

Zinc recovery from MSWI fly ash using acidic leaching and chemical precipitation was studied at pilot scale. The leached fly ash was re-incinerated in order to destroy toxic dioxins. 75–150 kg/h of fly ash from a Swedish Waste-to-Energy plant was mixed with scrubber liquids from the same flue gas treatment system in a continuously stirred vessel. The resulting slurry was dewatered in a vacuum belt filter. Hydroxide precipitation of the produced leachate, at a pH of around 9, followed by filtration of the formed crystals in a membrane filter press produced a filter cake with up to 80 wt% Zn(OH)2 in dry solids, calculated from Zn(tot). Up to 70% of the zinc content in the fly ash could be recovered. Two 4-hour full scale ash re-incineration tests were performed: leached fly ash was mixed with the waste at a ratio corresponding to a situation where all the fly ash was continuously re-incinerated. The tests showed only an 8% mass increase of produced fly ash, which means that most of it ended up in the bottom ash, although some elements could potentially accumulate in the system if all the fly ash was to be continuously re-incinerated. No negative effects were observed on the bottom ash quality, which suggests that a large portion of the toxic fly ash could be transformed into the bottom ash fraction

Comment

A chloride-based chemical-vapor-deposition (CVD) process has been successfully used to grow very high quality 3C-SiC epitaxial layers on on-axis α-SiC substrates. An accurate process parameters study was performed testing the effect of temperature, surface preparation, precursor ratios, nitrogen addition, and substrate polytype and polarity. The 3C layers deposited showed to be largely single-domain material of very high purity and of excellent electrical characteristics. A growth rate of up to 10 μm/h and a low background doping enable deposition of epitaxial layers suitable for MOSFET devices

Infrared spectroscopy of physisorbed and chemisorbed N-2 in the Pt(111)(3x3)N-2 structure

Using infrared spectroscopy and low electron energy diffraction, we have investigated the adsorption of N-2, at 30 K, on the Pt(111) and the Pt(111)(1x1)H surfaces. At monolayer coverage, N-2 orders in commensurate (3x3) structures on both surfaces, and we propose that the unit cells contain four molecules in each case. The infrared spectra reveal that N-2 exclusively physisorbs on the Pt(111)(1x1)H surface, while both physisorbed and chemisorbed N-2 is detected on the Pt(111) surface. Physisorbed N-2 is the majority species in the latter case, and the two adsorption states show an almost identical uptake behavior, which indicates that they are intrinsic constituents of the growing (3x3) N-2 islands. An analysis of the infrared absorbance data, based on a simple scaling concept suggested by density functional theory calculations, supports a model in which the (3x3) unit cell contains one chemisorbed molecule in end-on atop configuration and three physisorbed molecules. We note that a classic ''pinwheel'' structure on a hexagonal lattice, with the end-on chemisorbed N2 molecules acting as ''pins,'' is compatible with this composition. (C) 2007 American Institute of Physics

Thermodynamic potential of Rankine and flash cycles for waste heat recovery in a heavy duty Diesel engine

In heavy duty Diesel engines more than 50% of the fuel energy is not converted to brake power, but is lost as heat. One promising way to recapture a portion of this heat and convert it to power is by using thermodynamic power cycles. Using the heavy duty Diesel engine as the waste heat source, this paper evaluates and compares the thermodynamic potential of different working fluids in four power cycles: the Rankine cycle (RC), the transcritical Rankine cycle (TRC), the trilateral flash cycle (TFC) and the single flash cycle (SFC). To establish the heat input into the cycle, operating conditions from an actual heavy duty Diesel engine are used as boundary conditions for the cycle heat source. A GT-Power model of the engine was previously developed and experimentally validated for the stationary points in the European Stationary Cycle (ESC). An energy analysis of this engine revealed that it has four heat sources with the potential for waste heat recovery: the charge air cooler (CAC), the coolant flow, the exhaust gas recirculation cooler (EGRC), and the exhaust flow. Using fixed heat input conditions determined by the selected engine operating mode, the TFC performed best for the CAC with a net power increase of around 2 kW, while the RC performed best for the coolant flow, with a net power increase of 5 kW. For the EGRC, ethanol performed especially well with both the RC and TRC, leading to an 8 kW net power increase. When using the exhaust as heat source, all four cycles provided a power output of around 5 kW with some variation depending on the working fluid. This study shows that for most cases, considering the different heat sources, the choice of cycle has a larger impact on the cycle performance than the choice of working fluid