DESIGN AND TUNING OF A FUZZY CONTROLLER FOR INDOOR AIR QUALITY AND THERMAL COMFORT MANAGEMENT

This paper presents the development and testing of a multi objective fuzzy controller. It is dedicated to the control of thermal comfort and indoor air quality while minimising energy consumption and reducing instabilities are other constraints for this controller. After a brief introduction on the difficult task of indoor climate control, the test cell and its corresponding model is described in the second section. The model has been developed within TRNSYS. Section 3 describes the architecture of the fuzzy controller applied to these control objectives in the test cell. A hierarchical architecture has finally been selected since it is a very flexible architecture and it results in reducing the total number of fuzzy rules. The rule optimisation technique, based on genetic algorithms is also presented in the third section. Simulation results are finally presented. They prove that, after optimisation, the fuzzy controller greatly outperforms a typical ON-OFF controller on all control criteria. Energy consumption is in particular reduced by more than 10%. The fourth section of this chapter presents field experiments among 20 subjects of both ON-OFF control and fuzzy control. If major differences are not observed on the thermal comfort and indoor air quality point of view, these experiments however illustrate the importance of on-line tuning of specific fuzzy rules.     

1H-NMR study of bovine myoglobin autoxidation. Influence of muscle type and time post mortem

¹H NMR spectroscopy was used to determine first order rate constants at four temperatures (300, 304, 308, 312 K) and activation energies of the autoxidation reaction for oxymyoglobin. the haeminic pigment was purified from two bovine muscles with different colour stabilities ( psoas major (PM) and longissimus lumborum (LL)) at 2h (day 0) and 192 h (day 8) post mortem. to characterize this autoxidation reaction, we have focused attention on the time-temperature dependent disappearance of the Val-E11 methyl group signal. This study showed that, whatever the time post mortem , although the myoglobin autoxidation rate was greater for PM than for LL muscle, the activation energies were similar. It was also worth noting that, in the range 300–312 K, the average ratio of autoxidation rate constants between day 8 and day 0 was near 1.6 for the two muscles studied. It is reasonable to think that oxidative processes developed during 8 days meat storage have led to a structural change within the cavity of the heme pocket of the myoglobins. Moreover, only one orientation of the porphyrin within the heme pocket was noted for the two muscles studied.     

Playtime

Three installation projects take tropes such as the labyrinth, the lumberjack culture and the neighbor's fence, and turn them into spaces of gathering and play.     

Optimal parallel funding of research and development projects

To insure against the costs of failure, research managers often initiate several more-or-less independent research projects with the same target. But then they face the problem of how many parallel ”teams“ to fund in order to maximize the probability of a timely breakthrough. If there are too many teams, resources are stretched too thin, but if there are too few teams, an opportunity for exceptional achievement may be missed. Several possible project objectives are identified, including maximizing the achievement of the best team and maximizing the probability that at least one team will attain a threshold. General optimization problems based on these goals are then formulated in fixed, uncertain, and competitive environments. These problems are solved analytically and numerically for achievement distributions in a family based on the exponential distribution. The applicability of these solutions to funding R&D, and to other problems such as supporting athletes, is then discussed.     

Spalling and Cracking in Alumina by Compression

Crack damage produced by compressive loads in a dense alumina ceramic was studied with a replication technique that recorded damage done to the specimen's surface. The characteristics of the spalling produced in an externally pressurized, tubular specimen were evaluated at twelve stress levels up to failure. The study revealed that crack extension begins at a compressive stress approximately one quarter of that required to cause failure and that the amount of crack damage increases greatly as the failure stress is approached. The nature of the spalled particles and the mechanisms of spalling are discussed. Mechanisms of compressive failure are suggested.     

The optimal frequency and sequencing of tests in the inspection of multicharacteristic components

IIE Transactions - A product (component) often requires inspection on its characteristics, of which nonconformance of one would result in the rejection of the component. However, the need for...