Geometric phase for an accelerated two-level atom and the Unruh effect

We study, in the framework of open quantum systems, the geometric phase acquired by a uniformly accelerated two-level atom undergoing nonunitary evolution due to its coupling to a bath of fluctuating vacuum electromagnetic fields in the multipolar scheme. We find that the phase variation due to the acceleration can be in principle observed via atomic interferometry between the accelerated atom and the inertial one, thus providing an evidence of the Unruh effect.Comment: 12 pages, no figure

Minimum Ventilation Requirement and Associated Energy Cost for Aerial Ammonia Control in Broiler Houses

Minimum ventilation rate (MVR) and bird performance of four commercial-scale broiler houses were monitored for 16 consecutive growouts. A complete house clean-out was conducted after the 7th growout and again after the 13th growout. Between the clean-outs, only caked litter was removed, and new bedding was added to the old litter

Chapter 1: Basic Principles of the Thermal Environment and Livestock Energetics

Description of the thermal environment and the livestock response can be complex, and has been the subject of extensive research for over fiver decades inspired in part by a joint report sponsored by ASAE (now ASABE) and ASHRAE. This 1959 report presented the State of the Art of the thermal environmental requirements of poultry (Stewart and Hinkle, 1959), dairy cattle (Yeck, 1959), beef cattle (Nelson, 1959), swine (Bond, 1959) and sheep (Kelly, 1959). Even though the report was comprehensive, data were noted as being incomplete for understanding the biophysical interactions between the animal and its thermal environment as required for effective management and engineering design. Heat loss for poultry was primarily based on basal (fasted) conditions, for example, and the role of the skin and hair in heat dissipation from cattle was inadequate. Comprehensive studies have been conducted in the intervening 50 years to evaluate the effects of nutrition, acclimation or conditioning, dynamic changes in the environment, physiological state, and social interactions on livestock productivity responses to the thermal environment: temperature, humidity, radiation, and air velocity

Heat and Moisture Production of Poultry and Their Housing Systems: Broilers

Heat and moisture production rates (HP, MP) of modern broiler chickens (Cobb strain males) raised on litter in commercial production housing were determined from extensive environmental and production data of 20 house–flocks. The flock size was 18,800 birds, with a typical growth period of 56 days. Regression equations were established that predict total, sensible and latent HP of the broiler houses over common ranges of body mass (0.4 to 3.2 kg), house temperature (20 to 32C), relative humidity (30–80%), and photoperiod (light or dark). Specific total HP rate from this study was up to 31% higher than found elsewhere at 0.4 kg body mass, and the difference diminished as mass approached 2.3 kg. Modern broiler houses have reduced MP that presumably resulted from use of nipple drinkers as opposed to trough drinkers on which most of the literature data were based. The new HP and MP data are expected to enhance efficient design and operation of modern broiler housing ventilation systems. The results further confirm the need to systematically update literature HP and MP data for engineering practices

Temperature and Humidity Profiles of Broiler Houses with Experimental Conventional and Tunnel Ventilation Systems

This article describes the spatial and diurnal patterns of air temperature and relative humidity (RH) in commercial-scale broiler houses (12 ¥ 122 m, 40 ¥ 400 ft) using experimental conventional and tunnel heating, cooling, and ventilation systems. The experimental broiler houses used 76-cm (2.5-ft) side curtains and combined mechanical and natural ventilation. Heating was provided by propane brooders and space furnaces. Cooling was accomplished with side-mounted cooling fans and misting nozzles in the conventional houses, but with fans and evaporative cooling pads in the tunnel houses. Interior mixing fans, arranged to circulate air in a “racetrack” fashion, were used in the tunnel houses

Prediction of Black Globe Humidity Index in Poultry Buildings

A computer model was developed to predict the black globe humidity index (BGHI) to simulate different resultant conditions in designing poultry buildings. The simulated BGHI values were compared to experimental measurements, obtained in a poultry facility at Viçosa, MG, Brazil, giving a mean deviation of 1.31 %. The model was then used to predict BGHI values as affected by roof slopes of 25º, 30º, and 35º, and column heights of 3.0 and 3.5 m. The results showed that BGHI can be reduced by 0.12 units per 5º increase in roof slope, or 0.10 units per 0.5 m increase in column height. The maximum reduction of BGHI, 0.33 units, was obtained when comparing the extreme conditions of 25º roof slope and 3.0 m height vs. 35º slope and 3.5 m height

Data Feel: Exploring Visual Effects in Video Games to Support Sensemaking Tasks

This paper explores the use of visual effects common in video games that support a range of tasks that are similar in many ways to analysis tasks supported in visual analytics tools. While some visual effects are meant to increase engagement or to support a game's overall visual design, we find that in many games visual effects are used throughout gameplay in order to assist a player in reasoning about the game world. In this work, we survey popular games across a range of categories (from casual games to "Triple A" games), focusing specifically on visual effects that support a player's sensemaking within the game world. Based on our analysis of these games, we identify a range of tasks that could benefit from the use of "data feel," and advocate for the continued investigation of visual effects and their application in data visualization software tools.Comment: 7 pages, 5 figures, VIS4DH 202

Energy Use Analysis of Open-Curtain vs. Totally Enclosed Broiler Houses in Northwest Arkansas

Seventeen years of electricity and propane fuel use data collected from broiler production houses at the University of Arkansas Applied Broiler Research Farm (ABRF) in Northwest Arkansas were analyzed to quantify relative effect of open-curtain vs. enclosed housing systems on energy use. The ABRF consists of four commercial-scale 12 x 121 m (40 × 400 ft) houses and raise broilers under standard production contracts. After the first sixteen years of production under open-curtain system, all four houses were converted to solid-wall enclosed system with dropped ceiling, tunnel ventilation and cooling pads in early 2006. Energy use data collected from each house included propane fuel use for heating and electricity use for ventilation fans, lighting, and total. Analyses of energy use before and after the renovation were made on a flock or yearly basis. Heating degree days are the major factor affecting propane fuel usage, as expected. Bird age and outside temperature were found to be the major factors affecting fan electricity usage for the enclosed system. Electricity for ventilation and lighting comprised about 85% of total usage. Annual electricity usage was higher with the enclosed system than with the open-curtain system due to loss of natural daylight and increased mechanical ventilation in the enclosed system. Higher cost of fuel than electricity resulted in higher fuel expenditure for winter heating than electricity expenditure for summer cooling in this region. With increasing energy costs, analysis of energy use, as conducted in this study, will prove conducive to improving energy efficiency or alternative energy application