Search

This project was a simulation study of the energy performance of a prototype three-story office building configured for both conventional overhead (OH) air conditioning and underfloor air distribution (UFAD). Both the annual energy consumption and the peak demand were calculated using EnergyPlus v3.0 for the building in three California climate zones, Los Angeles, Sacramento and San Francisco. The sensitivity of the energy performance to the building configuration (e.g., window to wall area ratio, etc.) and other features of the building was studied. The main result of the study was that UFAD provides energy savings compared to OH in all three climate zones, both in terms of annual energy consumption and also in the reduction of peak demand HVAC annual energy reductions were greater in San Francisco but only marginally better than in the warmer climate zones of Los Angeles and Sacramento. A second major outcome of this study was improvements to the UFAD implementation in the recently released EnergyPlus v3.1. These involved improvements in stratification modeling in interior zones, addition of perimeter zone stratification models, creation of a whole building template model, and user documentation to eScholarship provides open access, scholarly publishing services to the University of California and delivers a dynamic research platform to scholars worldwide. facilitate use of the new capabilities. Finally, the effectiveness of various demand response actions such as raising the room setpoint temperature and reducing internal lighting and equipment loads was evaluated. Raising the setpoint temperature was found to be the most effective measure to reduce peak demand.

The probabilistic uncertainty assessment of geomechanical risk—specifically, caprock failure—attributable to CO2 injection, as presented in a simplified hypothetical geological model, was the focus of this study. Our approach amalgamates the implementation of a multilaminate model, the creation of a response surface model in conjunction with the Box–Behnken sampling design, the execution of associated numerical modeling experiments, and the utilization of Monte Carlo simulations. Probability distributions to encapsulate the inherent variability (elastic and mechanical properties of the caprock and reservoir) and uncertainty in prediction estimates (vertical displacement, total strain, and F value) were employed. Our findings reveal that the Young modulus of the caprock is a key factor controlling equivalent total strain but is insufficient as a stand-alone indicator of caprock integrity. It is confirmed that the caprock can accommodate significant deformation without failure, if it possesses a low Young's modulus and high mechanical strength properties, such as the friction angle and uniaxial compressive strength. Similarly, vertical displacement was found to be an unreliable indicator for caprock integrity, as caprock failure can occur across a broad spectrum of vertical displacements, particularly when both the Young modulus and mechanical strength properties have wide ranges. This study introduces the F value as the most dependable indicator for caprock failure, although it is a theoretical attribute (the shortest distance between the Mohr circle and the nearest failure envelope used to measure the sensitivity to failure) and not physically measurable in the field. Deviatoric stress levels were found to vary based on stress regimes, with the maximum levels observed under extensive and compressive stress regimes. In conjunction with the use of the response surface method, this study demonstrates the efficacy of the multilaminate framework and the Mohr–Coulomb constitutive model in providing a simplified, yet effective, probabilistic model of the mechanical behavior of caprock failure, reducing mathematical and computational complexities. [ABSTRACT FROM AUTHOR]

Large amounts of energy are consumed by air-conditioning systems to maintain tight control of air temperature in rooms--a narrow range of temperature excursion from neutral, and a uniform temperature in the ambient space. However, both field and lab studies are showing that neither narrow range nor uniformity is really necessary for providing occupant comfort. Data from several large field studies shows occupants accepting a much wider temperature range than is typically applied in practice (Arens 2009). In addition, if occupants have access to a personal environmental control (PEC) system, the acceptable ambient temperature range can be further extended, to as much as 18-30ºC (Zhang H 2009, Amai 2005, Zhang Y 2008). By targeting specific body parts, PEC systems produce equivalent comfort using much less energy than is needed to condition the entire ambient space.Energy is also required consumed in fans and mixing diffusers to produce uniform room temperature conditions. To assure complete mixing, diffuser manufacturers specify minimum supply volumes that are as high as 50% of maximum volume. Some engineers have been successfully operating buildings well below these volume minima, and research is now underway to quantify the acceptability of their non-uniform environments to their occupants. Substantial fan energy savings are possible, and recent changes to energy standards (ASHRAE 2009) have begun to require a lower minimum.This paper simulates the energy savings possible from through these two approaches to providing comfort in less tightly controlled spaces. Their savings are substantial and justify looking into how they might be incorporated into building design and operation.

The current study applies implicit theory as a theoretical lens to explore gender differences in explicit and implicit measures of robot attitudes, which in turn facilitates behavioral intention. In total, 108 participants assessed the modified Robot Implicit Association Test (RIAT) to complete both implicit measures of attitudes and explicit self-reported measures in randomized order. Our findings demonstrated that (a) implicit attitudes (RIAT D-scores) were significantly correlated with self-reported measures (explicit attitude, perceived technology innovativeness, and behavioral intention), (b) different patterns of explicit and implicit attitudes exist, and (c) males may have a more favorable preference toward service robots than females. These results help build theoretical and methodological foundations for service management innovation into the role of implicit attitude in hospitality firms. [ABSTRACT FROM AUTHOR]