90 research outputs found

    Transient Overvoltage Testing of Environmental Controllers

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    The integrated electronic control system will provide a new method for the day-to-day management of environmental control of animal production systems. No standards are currently accepted for transient overvoltage protection of these controllers. To assess the adequacy of existing designs, a test circuit was designed and used for a transient open circuit over-voltage waveform (ANSI/IEEE C62.41-1980) of 16 environmental control units: a maximum spike of 770 V was applied to the power supplies, and a spike up to 100 V was applied to temperature sensor lines. For these relatively mild tests, no failures were noted due to power supply transients, but three units failed when subjected to transients on their temperature sensor lines. From this research it is suggested that an industry standard be adopted to define the minimum transient overvoltage design conditions by which environmental controllers should be tested

    Mechanical Backup Systems for Electronic Environmental Controllers

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    A series of mechanical backup systems for electronic environmental controllers is presented for a typical finishing swine barn and a typical tunnel ventilated broiler house. The systems consist of mechanical thermostats and timers used in parallel with the electronic controller, designed to ensure animal survival in the event of controller or related hardware failure. For swine housing, three distinct mechanical backup functions are identified; for broiler housing, four distinct mechanical backup functions are identified. Schematic diagrams of the mechanical backup functions are provided and their implementation is described

    A Survey of Electronic Environmental Controllers

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    Sixteen commercially available electronic environmental controllers were evaluated. The units were classified according to enclosure type, analog versus microprocessor based control, power supply, sensors, alarms, control relays and triac output, interval timers, outside temperature feedback, and retail price. An assessment of these controllers indicated several critical limitations in the application of this technology. The use of integrated controllers for animal production has the potential for substantial improvements in production efficiencies. If the limitations observed in the present controller technology, as represented by this sample, are addressed, industry acceptance of the technology can be accelerated. A uniform standard to address this technology is recommended and specific suggestions are provided for what the standard should address

    Assessing the Benefits of Misting–Cooling Systems for Growing/Finishing Swine as Affected by Environment and Pig Placement Date

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    The NCPIG swine growth model was used to evaluate swine growth performance for Wilmington, North Carolina; Bardstown and Mayfield, Kentucky; and Oklahoma City, Oklahoma as influenced by the use of a misting–cooling system. Five pig placement dates (Julian days 106, 126, 146, 166, and 186) were evaluated for each location using 22 years of weather data (1978–1999). The use of a misting system, while quite variable, was found to be generally profitable, reducing the length of the time to reach market weight. As the placement date increased, the average return to misting (/pig/year)decreasedfrom/pig/year) decreased from 8.12 to 1.98forOklahomaCity,from1.98 for Oklahoma City, from 6.00 to 1.16forWilmington,from1.16 for Wilmington, from 4.14 to 0.99forMayfield,andfrom0.99 for Mayfield, and from 3.07 to 0.87forBardstown.Basedontheproratedvalueof0.87 for Bardstown. Based on the prorated value of 1.39 per pig/per year for the cost of a misting system, probabilities for recovering the initial investment amount were determined for each pig placement date and location. These probabilities decreased as the pig placement date increased, except for Oklahoma City, which remained above 98% regardless of the date. For the locations other than Oklahoma City, the probabilities indicated that the earlier placement dates were more favorable for recovering the initial investment

    Air Quality and Emissions from Livestock and Poultry Production/Waste Management Systems

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    The objective of this paper is to summarize the available literature on the concentrations and emissions of odor, ammonia, nitrous oxide, hydrogen sulfide, methane, non-methane volatile organic carbon, dust, and microbial and endotoxin aerosols from livestock and poultry buildings and manure management systems (storage and treatment units).Animal production operations are a source of numerous airborne contaminants including gases, odor, dust, and microorganisms. Gases and odors are generated from livestock and poultry manure decomposition (1) shortly after it is produced, (2) during storage and treatment, and (3) during land application. Particulate matter and dust are primarily composed of feed and animal matter including hair, feathers, and feces. Microorganisms that populate the gastro-intestinal systems of animals are present in freshly excreted manure. Other types of microorganisms colonize the manure during the storage and treatment processes. The generation rates of odor, manure gases, microorganisms, particulates, and other constituents vary with weather, time, species, housing, manure handling system, feed type, and management system. Therefore, predicting the concentrations and emissions of these constituents is extremely difficult.Numerous control strategies are being investigated to reduce the generation of airborne materials. However, airborne contaminants will continue to be generated from livestock and poultry operations even when best management systems and/or mitigation techniques are employed.Livestock and poultry buildings may contain concentrations of contaminants that negatively affect human and animal health. Most of these health concerns are associated with chronic or longterm exposure to gases, dust, or microorganisms. However, acute or short-term exposures to high concentrations of certain constituents can also have a negative effect on both human and animal health. For example, the agitation and pumping of liquid manure inside a livestock building can generate concentrations of hydrogen sulfide that are lethal to humans and animals.Once airborne contaminants are generated they can be emitted from the sources (building, manure storage, manure treatment unit, or cropland) through ventilation systems or by natural (weather) forces. The quantification of emissions or emission rates for gases, odor, dust, and microorganisms from both point sources (buildings) and area sources (beef and dairy cattle feedlot surfaces, manure storage and treatment units and manure applied on cropland) is being intensely researched in the U.S., in many European countries, Japan, and Australia. However, the accurate quantification of emissions is difficult since so many factors (time of year and day, temperature, humidity, wind speed, solar intensity and other weather conditions, ventilation rates, housing type, manure properties or characteristics, and animal species, stocking density, and age) are involved in the generation and dispersion of airborne materials. Furthermore, there are no standardized methods for the collection, measurement and calculation of such constituents, resulting in significant variability and large ranges in the published literature. In fact, emission rates of only a few airborne contaminants have been investigated. Ammonia, hydrogen sulfide, and methane emissions have been more thoroughly studied than other gases and compounds because of the negative environmental impacts or human health concerns associated with them. Unfortunately, there is very little emission data for other contaminants such as odor, nitrous oxide, non-methane volatile organic compounds, dust, and endotoxins. The long-term impacts of these constituents on the environment and on human health are also not known

    Assessing the Benefits of Misting-Cooling Systems for Growing-Finishing Swine in Kentucky as Affected by Environment and Pig Placement Date

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    The growth performance of animals is often affected by extreme environmental conditions. In the case of swine, generally a cold environment will increase feed intake as the pig strives to maintain body temperature, while warmer environments may reduce growth, increase body maintenance demands, and subject the animal to environmental stress. Confinement houses are widely used as a primary means of modifying the environment to improve conditions for the growth of swine. Environment in these structures is usually controlled by natural or mechanical ventilation and by insulation for cold climates and limited use of evaporative cooling for summertime conditions

    Comparison of Observed and Simulated Grow-Finish Swine Performance Under Summer Conditions

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    As a part of a National Pork Producers Council educational program, our research and extension team at the University of Kentucky was linked with an independent commercial swine producer to test the NCPIG model against observed commercial on-farm data. This experience provided improved information for model development as well as increased producer insight into the data input needs and potential benefits of modeling. Detailed production information comparisons between the NCPIG model and producer data are presented for summer time conditions to assess the validity of the NCPIG model for simulation of grow-finish swine performance. Results demonstrated that the NCPIG model accurately simulated performance

    Time-Resolved Data Acquisition for In Situ Subsurface Planetary Geochemistry

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    The current gamma-ray/neutron instrumentation development effort at NASA Goddard Space Flight Center aims to extend the use of active pulsed neutron interrogation techniques to probe the subsurface geochemistry of planetary bodies in situ. All previous NASA planetary science missions, that used neutron and/or gamma-ray spectroscopy instruments, have relied on a constant neutron source produced from galactic cosmic rays. One of the distinguishing features of this effort is the inclusion of a high intensity 14.1 MeV pulsed neutron generator synchronized with a custom data acquisition system to time each event relative to the pulse. With usually only one opportunity to collect data, it is difficult to set a priori time-gating windows to obtain the best possible results. Acquiring time-tagged, event-by-event data from nuclear induced reactions provides raw data sets containing channel/energy, and event time for each gamma ray or neutron detected. The resulting data set can be plotted as a function of time or energy using optimized analysis windows after the data are acquired. Time windows can now be chosen to produce energy spectra that yield the most statistically significant and accurate elemental composition results that can be derived from the complete data set. The advantages of post-processing gamma-ray time-tagged event-by-event data in experimental tests using our prototype instrument will be demonstrated

    The Vehicle, 1963, Vol. 5

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    Vol. 5 Table of Contents Milepostspage 3 Rhyme Conceived At DawnDaun Alan Leggpage 4 NightRoss Kokospage 4 UncrownedOra Blanche T. Kingpage 4 SunfishingL.J.G.page 5 The Man Who Went To New YorkEric Crookspage 7 The DreamPauline B. Smithpage 18 Open WindowsDavid Helmpage 19 SalvationChristine McCollpage 19 The Chess GamePierre Hooverpage 20 CataclysmRaymond Kapraunpage 20 A Microscopic ViewKenneth L. Vadovskypage 21 See How Love ComesLiz Puckettpage 21 A Can Of Beer For AndyKenneth L. Vadovskypage 22 A MonsterDixie Lee Motleypage 28 InconstancyJanice Brookspage 29 DreamerDaun Alan Leggpage 29 The Third WishGlenda Vursellpage 30 The MiracleJanice Brookspage 32 What Lives Where Love Once Dwelt?Vernell Vyvialpage 33 The Most Unforgettable Person I Have Ever KnownJames Flingpage 34 Winter ThoughtsPauline B. Smithpage 35 A Winter NightPeggy Lambertpage 35 The Silver WhaleL.J.G.page 36 RaindropsDixie Lee Motleypage 40 Conflict Of Soul IJean Konzelmanpage 40 JudyChristine McCollpage 41 Sadness No. 3 (Vergessen)Sherry Sue Frypage 41 Lost GoldLarry Pricepage 42 EchoesCharles Cooleypage 48 TruthDaun Alan Leggpage 48 SunsetCarol Bennettpage 48 Cover designTom Windsor Illustration for winning storyJoel E. Hendrickshttps://thekeep.eiu.edu/vehicle/1011/thumbnail.jp

    Effects of dipole position, orientation and noise on the accuracy of EEG source localization

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    BACKGROUND: The electroencephalogram (EEG) reflects the electrical activity in the brain on the surface of scalp. A major challenge in this field is the localization of sources in the brain responsible for eliciting the EEG signal measured at the scalp. In order to estimate the location of these sources, one must correctly model the sources, i.e., dipoles, as well as the volume conductor in which the resulting currents flow. In this study, we investigate the effects of dipole depth and orientation on source localization with varying sets of simulated random noise in 4 realistic head models. METHODS: Dipole simulations were performed using realistic head models and using the boundary element method (BEM). In all, 92 dipole locations placed in temporal and parietal regions of the head with varying depth and orientation were investigated along with 6 different levels of simulated random noise. Localization errors due to dipole depth, orientation and noise were investigated. RESULTS: The results indicate that there are no significant differences in localization error due tangential and radial dipoles. With high levels of simulated Gaussian noise, localization errors are depth-dependant. For low levels of added noise, errors are similar for both deep and superficial sources. CONCLUSION: It was found that if the signal-to-noise ratio is above a certain threshold, localization errors in realistic head models are, on average the same for deep and superficial sources. As the noise increases, localization errors increase, particularly for deep sources
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