A multi-zone air-handling unit was popular several decades ago due to the convenience of small sized modular units, which were inexpensive to install and easily maintained in a mechanical room. The cost and convenience proved to be of little benefit as the units perform poorly from an energy usage perspective. A “three-deck” multi-zone unit is a hybrid of its kind, and it can be very efficient ...

Recent data have radically altered the X-ray perspective on cooling flow clusters. X-ray spectra show that very little of the hot intracluster medium is cooler than about 1 keV, despite having short cooling times. In an increasing number of cooling flow clusters, the lobes of a central radio source are found to have created cavities in the hot gas. Generally, the cavities are not overpressured ...

The energy performance of buildings depends on how effectively the building envelope responds to climate. Architects, therefore, need to design building envelopes with the consideration of local climate characteristics in the early design stage. Simplified formulas were used that evaluate the heating and cooling energy demand of building envelopes, which were applied to a model building with en...

This paper describes the results of a preliminary study to determine the e€ective heating and cooling time constants of ionospheric currents in a simulated modulated HF heating, `beam painting' con®guration. It has been found that even and odd harmonics of the fundamental ELF wave used to amplitude modulate the HF heater are sourced from di€erent regions of the ionosphere which support signi®ca...

The cooling-flow problem is a long-standing puzzle that has received considerable recent attention, in part because the mechanism that quenches cooling flows in galaxy clusters is likely to be the same mechanism that sharply truncates the high end of the galaxy luminosity function. Most of the recent models for halting cooling in clusters have focused on AGN heating, but the actual heating mech...

Heat pump technology has been rapidly developed recently as a clean and efficient heating method. Continuous capacity modulation of heat pumps is necessary for enhancing room thermal comfort and reducing start-stop losses. A novel capacity modulation method for the scroll compressor heat pump system based on refrigerant injection and refrigerant release is proposed. The experiments indicate the...