Airborne Advanced Reconfigurable Computer System (ARCS)

A digital computer subsystem fault-tolerant concept was defined, and the potential benefits and costs of such a subsystem were assessed when used as the central element of a new transport's flight control system. The derived advanced reconfigurable computer system (ARCS) is a triple-redundant computer subsystem that automatically reconfigures, under multiple fault conditions, from triplex to duplex to simplex operation, with redundancy recovery if the fault condition is transient. The study included criteria development covering factors at the aircraft's operation level that would influence the design of a fault-tolerant system for commercial airline use. A new reliability analysis tool was developed for evaluating redundant, fault-tolerant system availability and survivability; and a stringent digital system software design methodology was used to achieve design/implementation visibility

Determination of fungal activity in modified wood by means of micro-calorimetry and determination of total esterase activity

Beech and pine wood blocks were treated with 1,3-dimethylol-4,5-dihydroxyethylen urea (DMDHEU) to increasing weight percent gains (WPG). The resistance of the treated specimens against Trametes versicolor and Coniophora puteana, determined as mass loss, increased with increasing WPG of DMDHEU. Metabolic activity of the fungi in the wood blocks was assessed as total esterase activity (TEA) based on the hydrolysis of fluorescein diacetate and as heat or energy production determined by isothermal micro-calorimetry. Both methods revealed that the fungal activity was related with the WPG and the mass loss caused by the fungi. Still, fungal activity was detected even in wood blocks of the highest WPG and showed that the treatment was not toxic to the fungi. Energy production showed a higher consistency with the mass loss after decay than TEA; higher mass loss was more stringently reflected by higher heat production rate. Heat production did not proceed linearly, possibly due to the inhibition of fungal activity by an excess of carbon dioxide

Undersökning av olika träbaserade skivors "mögelbenägenhet"

Undersökningarna visar att samtliga testade skivtyper (fiberskivor, spånskivor, plywood, gipsskivor, dessutom splintved av tall och gran samt splintved av tall behandlad med natriumbenzoat) i större eller mindre utsträckning kunde angripas av mögel och blånadssvampar vid accelererade provningar i laboratorium. I stort sett möglade spånskivor fortast, därnäst fiberskivor och sedan plywood

Microcalorimetric measurements of metabolic activity of six decay fungi on spruce wood as a function of temperature

Microcalorimetry, i.e., the measurement of heat production rate was used to assess the metabolic activity of six wood-decay fungi growing on moist wood particles as a function of the temperature. Four brown-rot fungi increased their activity with increasing temperature in the temperature range 5-35 C, and one brown-rot and the white-rot fungus had a lower activity at 35 C than at 25 C. It may be possible to estimate the relative growth rate of a fungus in relation to different environmental factors by measurements of the production of heat if there are no transient effects. The possible use of the results is discussed for three applications: hazard evaluation of large piles of moist biological fuels, brown-rot degradation of wood constructions, and detoxification by white rot fungi of soils containing recalcitrant toxic chemicals

Undersökning av olika träbaserade skivors "mögelbenägenhet"

Undersökningarna visar att samtliga testade skivtyper (fiberskivor, spånskivor, plywood, gipsskivor, dessutom splintved av tall och gran samt splintved av tall behandlad med natriumbenzoat) i större eller mindre utsträckning kunde angripas av mögel och blånadssvampar vid accelererade provningar i laboratorium. I stort sett möglade spånskivor fortast, därnäst fiberskivor och sedan plywood

Measurements on two mould fungi with a calorespirometric method

This paper presents results from dynamic calorespirometric measurements on the two mould fungi Penicillium roqueforti and P. camemberti growing on agar. The measurements were made with two isothermal heat conduction calorimeters connected by a tube. In one of the calorimeters, the sample was placed and the other contained a carbon dioxide absorbent. Pressure sensors were connected to both the ampoules. The equipment also contained a valve on the tube that was opened and closed at regular intervals. Measurements were started at normal atmospheric pressure and gas composition, and continued after oxygen was consumed. The response of the fungi to the changing gas composition was followed and gas exchange ratios and metabolic enthalpies were calculated by approximate methods. (C) 2004 Published by Elsevier B.V