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The Peace Tower, built between 1919-27, is a 92 metre (302 ft) high campanile at the main entrance to the Canadian Houses of Parliament in Ottawa. By 1990, the exterior masonry had deteriorated and cracked. This resulted in a major masonry conservation project, completed in 1996, which included re-pointing, stone repair, grouting and improved water-shedding details. A comprehensive monitoring program was subsequently commissioned to monitor hygrothermal performance and structural movement. The main objective is to evaluate the long-term performance of the tower and, in particular, the impact of the conservation work on the behaviour of the composite masonry concrete exterior walls under varying environmental conditions. Data from the monitoring provides a greater understanding of in-service behaviour and provides input for analytical modelling. The program also provides an early warning system to facilitate an effective maintenance program. This paper describes the monitoring program and presents some of the results.

This research examined the thermal diffusion of water vapour through glass fibre insulation. A set of published results of thermal tests on glass fibre insulation (when wet and dry) was analyzed to derive the thermal diffusion coefficient for water vapour through glass fibre insulation., e-Sim 2004 Conference: 10 June 2004, Vancouver, B.C.

Strenuous exercise causes an increase in extracellular [K(+)] and intracellular Na(+) ([Na(+)](i)) of working muscles, which may reduce sarcolemma excitability. The excitability of the sarcolemma is, however, to some extent protected by a concomitant increase in the activity of muscle Na(+)-K(+) pumps. The exercise-induced build-up of extracellular K(+) is most likely larger in the T-tubules than in the interstitium but the significance of the cation shifts and Na(+)-K(+) pump for the excitability of the T-tubular membrane and the voltage sensors is largely unknown. Using mechanically skinned fibres, we here study the role of the Na(+)-K(+) pump in maintaining T-tubular function in fibres with reduced chemical K(+) gradient. The Na(+)-K(+) pump activity was manipulated by changing [Na(+)](i). The responsiveness of the T-tubules was evaluated from the excitation-induced force production of the fibres. Compared to control twitch force in fibres with a close to normal intracellular [K(+)] ([K(+)](i)), a reduction in [K(+)](i) to below 60 mM significantly reduced twitch force. Between 10 and 50 mM Na(+), the reduction in force depended on [Na(+)](i), the twitch force at 40 mM K(+) being 22 +/- 4 and 54 +/- 9% (of control force) at a [Na(+)](i) of 10 and 20 mM, respectively (n= 4). Double pulse stimulation of fibres at low [K(+)](i) showed that although elevated [Na(+)](i) increased the responsiveness to single action potentials, it reduced the capacity of the T-tubules to respond to high frequency stimulation. It is concluded that a reduction in the chemical gradient for K(+), as takes place during intensive exercise, may depress T-tubular function, but that a concomitant exercise-induced increase in [Na(+)](i) protects T-tubular function by stimulating the Na(+)-K(+) pump.

ASHRAE Research Project 515 had the goal of producing measured values of the dynamic heat transmission characteristics of walls. The characteristics were measured in a guarded hot box facility. The facility, which conforms in general to that standardized by ASTM C236, measuresheat transfer through a 2440 mm X 2440 mm (8ft X 8ft) test area. Calorimeter temperatures are controllable between l6°C and 26°C (60°F and 80°F), and cold-side temperatures are controllable between 0°C and -40°C (32 °F and -40°F). Data acquisition and control are provided through a laboratory computer system. Dynamic calibration of the guarded hot box facility wasrequired before it could be used to measure dynamic heat transmission characteristics. This calibration was developed from first principles and supported by measurements of a 102 mm (4 in.) thick expanded polystyrene specimen whose thermal characteristics had been determined from measurements of material properties. To measure the dynamic heat transmission characteristics of wall specimens, a test and data reduction procedure was also developed from first principles. The validity of this procedure was confirmed with measurements of the dynamic heat transmission characteristics of a 203 mm (8 in.) thick cement mortar -- specimen whose thermal characteristics were determined from measurements of material properties., Paper presented at the ASHRAE Winter Meeting held in Chicago, IL, USA, January 23-27, 1993

ASHRAE Research Project 515 had the goal of producing measured dynamic heat transmission characteristics of walls. The work was undertaken utilizing a guarded hot box facility. The measured dynamic heat transmission characteristics are used to confirm the data and procedures provided in the ASHRAE Handbook-Fundamentals for predicting dynamic heat transfer. The steady-state (thermal resistance) and dynamic heat transmission characteristics of seven wall specimens were measured. The test specimens represented wall types ranging in construction from an insulated steel stud wall with stucco finish to air insulated concrete block wall with brick veneer finish. For all specimens, the measured frequency response compared quite well with the predicted frequency response. On the other hand, the measured thermal resistance varied from 45% to 90% of the predicted them1al resistance. It is concluded that, within the constraints imposed on the equations and data and assuming actual assembly thermal resistance, heat flux predicted using the Handbook z-transfer function coefficients will be accurate enough for practical purposes., Paper presented at the ASHRAE Winter Meeting held in Chicago, IL, USA, January 23-27, 1993