A Progress Report on the Performance of Growing-Finishing Swine Under Different Environmental Conditions

Another series of trials have been completed on the effects of various floor types, number of pigs per pen and open versus insulated, ventilated housing on the performance of growing-finishing pigs. The floor types were: 10 0% slotted , 5 0% slotted, 2 5 % slotted, and concrete with a narrow, deep gutter across the end of the pen. The slats were 5 inch wide reinforced concrete. Pits under the floor accumulated the manure. Pen sizes were either 5 x 15 feet or 10 x 15 feet. Eight or 9 pigs were placed in the smaller pens and the number of pigs was doubled in the larger pens. The pigs used in these trials were SPF Hampshire, Yorkshire, and Duree crossbred pigs. A 22 x 22 foot house with an adjoining outside concrete pen was used to compare the performance of pigs reared in this environment with the pigs in the insulated, ventilated house. Bedding was used in this house during both trials and the pigs were watered outside. One of two groups in this house was fed inside and the other was fed outside

Swine Housing Research - Southeast Experiment Farm

The development of the Southeastern Experimental Farm has created the opportunity for studies in swine housing management. Initial steps taken to develop a program were the construction of three temporary structures, which were described in the 1963 Animal Science Mimeo Series. Results of the first summer study (A.S. Mimeo 63 -1) were reported. Daily gains and feed required per pound of gain were approximately the same among pigs on slotted floor, concrete floor with slotted dunging alley and concrete floor with bedding. More labor was required for the conventional concrete floor and sloping floor than was required for the completely slotted floor. In 1963 all were removed and the farm was repopulated with SPF (specific pathogen free) pigs. The uninsulated temporary house was moved to pasture for the two insulated houses were used for growing-finishing 1963-64 and the summer of 1964

Swine Housing Studies: Type of Floors, Insulation and Methods of Handeling Waste

Swine housing is in an era of research, new ideas, and changes. Never before have we been more conscious of housing management and facilities for swine. Many swine producers are wondering if they should continue with the same facilities, or remodel the existing buildings, or construct a new building. If the producer decides to change or remodel, then a barrage of questions should be answered. Important considerations are: Complete confinement or pasture? What floor plan and manure handling method? Should the building be enclosed, insulated, ventilated, and how much automatic equipment? Perhaps we should make it clear in this paper that the authors are not suggesting a change should be made by swine producers, but rather swine can be profitably reared with good management under many conditions on pasture, in confinement, or a combination of pasture and confinement. Confinement rearing is relatively new and many new ideas are being tested. The purpose of this research is to provide information on some of these ideas

Performance of Growing-Finishing Swine Under Different Environmental Conditions

The performance of growing-finishing pigs maintained in pens with different floor construction has been studied in two experiments (winter and summer). The four types of floor construction are: completely slotted, 5CY/o slotted, 25% slotted and a sloped concrete floor with a narrow gutter across the lower end of the pen. Pits under the slotted floors accumulate the manure. In addition to floor type, a comparison has been made of number of pigs per pen and controlled and uncontrolled house temperatures. Pen size was 5 x 15 feet when 8 or 9 pigs were used per pen and 10 x 15 feet when the pig numbers were doubled thus allowing the same number of square feet per pig. Feeder and water space per pig was also equalized between lots. During the winter trial two lots of pigs were also confined in an uninsulated house and bedded with straw. Feeders and waters were located inside of these houses. Identical rations were fed to all lots of pigs in both experiments. The composition of the rations fed are shown in Table 1

Power electronics and electric machinery challenges and opportunities in electric and hybrid vehicles

The development of power electronics and electric machinery presents significant challenges to the advancement of electric and hybrid vehicles. Electronic components and systems development for vehicle applications have progressed from the replacement of mechanical systems to the availability of features that can only be realized through interacting electronic controls and devices. Near-term applications of power electronics in vehicles will enable integrated powertrain controls, integrated chassis system controls, and navigation and communications systems. Future applications of optimized electric machinery will enable highly efficient and lightweight systems. This paper will explore the areas where research and development is required to ensure the continued development of power electronics and electric machines to meet the rigorous demands of automotive applications. Additionally, recent advances in automotive related power electronics and electric machinery at Oak Ridge National Laboratory will be explained. 3 refs., 5 figs

Numerical convergence of the block-maxima approach to the Generalized Extreme Value distribution

In this paper we perform an analytical and numerical study of Extreme Value distributions in discrete dynamical systems. In this setting, recent works have shown how to get a statistics of extremes in agreement with the classical Extreme Value Theory. We pursue these investigations by giving analytical expressions of Extreme Value distribution parameters for maps that have an absolutely continuous invariant measure. We compare these analytical results with numerical experiments in which we study the convergence to limiting distributions using the so called block-maxima approach, pointing out in which cases we obtain robust estimation of parameters. In regular maps for which mixing properties do not hold, we show that the fitting procedure to the classical Extreme Value Distribution fails, as expected. However, we obtain an empirical distribution that can be explained starting from a different observable function for which Nicolis et al. [2006] have found analytical results.Comment: 34 pages, 7 figures; Journal of Statistical Physics 201

Crystallization of a classical two-dimensional electron system: Positional and orientational orders

Crystallization of a classical two-dimensional one-component plasma (electrons interacting with the Coulomb repulsion in a uniform neutralizing positive background) is investigated with a molecular dynamics simulation. The positional and the orientational correlation functions are calculated for the first time. We have found an indication that the solid phase has a quasi-long-range (power-law) positional order along with a long-range orientational order. This indicates that, although the long-range Coulomb interaction is outside the scope of Mermin's theorem, the absence of ordinary crystalline order at finite temperatures applies to the electron system as well. The `hexatic' phase, which is predicted between the liquid and the solid phases by the Kosterlitz-Thouless-Halperin-Nelson-Young theory, is also discussed.Comment: 3 pages, 4 figures; Corrected typos; Double columne

A delta configured auxiliary resonant snubber inverter

A delta ({Delta}) configured auxiliary resonant snubber inverter is developed to overcome the voltage floating problem in a wye (Y) configured resonant snubber inverter. The proposed inverter is to connect auxiliary resonant branches between phase outputs to avoid a floating point voltage which may cause over-voltage failure of the auxiliary switches. Each auxiliary branch consists of a resonant inductor and a reverse blocking auxiliary switch. Instead of using an anti-paralleled diode to allow resonant current to flow in the reverse direction, as in the Y-configured version, the resonant branch in the {Delta}-configured version must block the negative voltage, typically done by a series diode. This paper shows single-phase and three-phase versions of {Delta}-configured resonant snubber inverters and describes in detail the operating principle of a single-phase version. The extended three-phase version is proposed with non-adjacent state space vector modulation. For hardware implementation, a single-phase 1-kW unit and a three-phase 100-kW unit were built to prove the concept. Experimental results show the superiority of the proposed topology

Electronic Structure of Calcium Hexaboride within the Weighted Density Approximation

We report calculations of the electronic structure of CaB$_6$ using the weighted density approximation (WDA) to density functional theory. We find a semiconducting band structure with a sizable gap, in contrast to local density approximation (LDA) results, but in accord with recent experimental data. In particular, we find an $X$-point band gap of 0.8 eV. The WDA correction of the LDA error in describing the electronic structure of CaB$_6$ is discussed in terms of the orbital character of the bands and the better cancelation of self-interactions within the WDA.Comment: 1 figur