John E. Seem

Learn More
This paper presents a new method for monitoring the performance of control loops. The method determines performance indices using recursive relationships. The recursive formulation gives the method two desirable characteristics, namely, it is computationally efficient, and the memory requirements are small because only previous values of the performance(More)
The air-side economizers have been developed as a major class of energy-saving equipment to enhance the energy efficiency of central airconditioning systems by taking advantage of outdoor air during cool or cold weather. In current practice, the outdoor air damper is controlled to maintain either the maximum or minimum opening by comparing the outdoor air(More)
DISCLAIMER This report was prepared as the result of work sponsored by the California Energy Commission. It does not necessarily represent the views of the Energy Commission, its employees or the State of California. The Energy Commission, the State of California, its employees, contractors and subcontractors make no warranty, express or implied, and assume(More)
This paper reports a comparison of models for estimating the return time from a night setback condition. Fifty-seven models are compared using simulation data that include the influence of climate, building mass, controller tuning, room orientation, and the unoccupied control strategy on return time. Two-parameter models are recommended for estimating the(More)
The chilled-water systems, mainly consisting of electric chillers and cooling towers, are crucial for the ventilating and air conditioning systems in commercial buildings. Energy efficient operation of such systems is thus important for the energy saving of commercial buildings. This paper presents an extremum seeking control (ESC) scheme for energy(More)
The Hybrid Ground Source Heat Pump (GSHP) system features the combination of ground heat exchanger (GHE) and cooling tower for rejecting the cooling load, which enables the use of the renewable resource of geothermal energy while reducing the cost of installation for applications of high cooling demand. However, model based control for efficient operation(More)