The shift to group-housing of the breeding herd makes it difficult to manage animals individually. To maximize sow longevity and reproductive performance, gilts must be bred on second heat weighing between 135 and 160 kg. As gilts are typically fed ad libitum (AD), they often exceed targeted breeding weights, leading to structural and other problems resulting in culling at early parities. Thus, utilization of an electronic sow feeder (ESF) enables caretakers to manage animals individually in group-housing situations, by allotting predetermined amounts of feed. The specific objectives of this study were to: 1) to determine the effects of AD or restricted (RS) feeding bases (FB) on growth and sexual development in replacement gilts using an ESF; 2) to determine the growth and reproductive responses to gonadotropins in gilts fed on either AD or RS feeding bases using an ESF; and 3) to ascertain the effects of short-term increases in feed allowances on growth and sexual development in previously feed-restricted gilts using an ESF. Gilts employed in all studies were acclimated to an ESF (ACCUTEAM, Osborne Industries, Osborne, KS) beginning at 150 d of age, during a 10-d training period. Across all experiments, treatments were assigned at 160 d of age. In experiments 1 and 2, gilts received feed on either AD (5.00 kg/d) or RS (2.72 kg/d) bases. In the first study, estrus detection began at 160 d of age. In experiment 2, gilts assigned to receive gonadotropins were treated at 170 d of age, with estrus detection beginning the next d. Gilts fed on the RS basis were observed to have improved feed conversion efficiency compared to AD-fed gilts in experiments 1 and 2 (both P < 0.01); and flushed gilts in experiment 3 had G: F similar to RS gilts. Average daily gain was not affected by FB in the first and third experiments, however AD-fed gilts gained weight at a faster rate (P = 0.02) than RS gilts in experiment 2. Gilts fed AD consumed their allotments across more meals than those fed RS. Age at puberty onset was not affected by FB in any of the experiments. Further, P.G. 600 did not hasten the onset of puberty, irrespective of FB in experiment 2. In experiment 3, ovulation rate was numerically greatest for flushed gilts, and was significantly greater than RS gilts (P = 0.05). The ovulation rate for flushed gilts was similar to AD gilts. Across all experiments, feed disappearance was observed to decrease as AD-fed gilts approached estrus. In this series of experiments, FB did not alter puberty onset, however ovulation rate was increased when gilts were allocated short-term increases in feed allowances. Further, utilizing an ESF may augment current industry estrus detection methods by monitoring feeding behavior. / Doctor of Philosophy / On commercial swine operations in the U.S. sow removal rates due to death and culling exceed 40% annually. On average, sows are culled at parity 3 or 4, while at least this many parities are required before investment costs are recouped. Gilts are typically fed AD until BW of 135 kg are attained by approximately 200 d of age. Oftentimes, gilts fed on AD basis exceed targeted breeding weights, leading to structural and other problems resulting in culling at early parities. To improve sustainability and competitiveness of pork production systems, the industry must focus on proper gilt management practices to facilitate successful entry into the breeding herd and increase longevity and lifetime performance as sows. A series of 3 experiments were conducted to evaluate different feeding bases on growth and sexual development in gilts. The first experiment evaluated the impact of AD or RS feeding on growth and sexual development in gilts using an ESF. Age at puberty was not different in limit-fed gilts. Limit-fed gilts also grew at a similar rate accompanied with improved feed conversion compared to AD fed gilts. Results from this experiment indicate that gilts can be limit-fed prior during the period around puberty until entering the breeding herd without negative impacts to growth or sexual development. In the second experiment, the same feeding bases were utilized, but within feeding basis groups, gilts either received or did not receive treatment with exogenous gonadotropins. Age at puberty was similar, regardless of feeding basis or gonadotropin treatment. Feed conversion was improved in limit-fed gilts, however daily gain was improved for gilts receiving feed AD. Results from this experiment imply that limit feeding gilts has no negative impacts on sexual development, but daily gain is reduced. In the third experiment, previous feeding bases were used, and a third, nutritional flushing, was also studied, when gilts received AD feed 7 d after first estrus. Flushed gilts had feed conversion like that of limit-fed gilts with daily gain similar to that of AD gilts. Gilts which were flushed had ovulation rates which were similar to gilts receiving feed AD but was greater compared with limit-fed gilts. Results indicate that flush feeding can achieve daily gain similar to ad libitum feeding and feed conversion similar to limit-feeding, while improving ovulation rate compared to limit-feeding. Across all studies, feed disappearance decreased for AD fed gilts as they neared estrus. Overall, using an ESF allows for precise feeding of replacement gilts and allows producers to implement various feeding strategies across multiple animals on an individual basis. Monitoring feed behavior with an ESF may enhance current estrus detection practices.

Process planning is an important and integral part of operating a printed circuit board (PCB) assembly system effectively. The focus of this research is to develop a new solution approach to determine the component placement sequence and feeder assignment for a turret style Chip Shooter machine often used in PCB assembly systems. This solution approach can be integrated into a process planning system to reduce assembly time and improve productivity. The Chip Shooter machine consists of three primary mechanisms: the turret head, a moving table, and the feeder carriage. These mechanisms move simultaneously in a cyclic manner to mount the components on the PCB. The mechanism with the longest movement time determines the placement time of a component. Therefore, the placement sequence of the components and the arrangement of the feeders in the feeder carriage directly affect the time required to mount all the components on a PCB. A placement time estimator function that accounts for the functional characteristic of the Chip Shooter machine is developed and is used to evaluate the performance of the solution approach presented in this research. The solution approach consists of a construction algorithm that uses a set of knowledge-based rules to construct an initial placement sequence and feeder assignment, and an improvement procedure to improve the initial solution. A case study is presented to validate the proposed solution approach. A Fuji CP4-3 machine and actual PCB data are used to test the performance of the proposed solution approach for different machine setup scenarios. The solutions obtained using the proposed solution approach are compared to those obtained using state of the art PCB assembly process optimization software. For all PCBs in the case study, the proposed solution approach yielded lower placement times than the commercial software, thus generating additional valuable production capacity. / Master of Science

Por mais de 30 anos, a utilização do meio de cultura, enriquecido com soro bovino, e de fibroblastos murinos, com a taxa de proliferação controlada por irradiação ou por ação de drogas anti-cancerígenas, vem desempenhando com sucesso o seu papel de auxiliar no desenvolvimento dos queratinócitos em cultura, para fins clínicos. Porém, atualmente há uma preocupação crescente acerca da possibilidade de transmissão de príons e virose animais, aos pacientes transplantados. Levando em conta esta preocupação, o presente trabalho tem como objetivo cultivar fibroblastos humanos em meio enriquecido com lisado de plaquetas humanas e determinar a dose de irradiação dessas células, para obtenção da camada de sustentação na cultura de células da epiderme. Para realização do objetivo proposto, padronizamos a lise das plaquetas, utilizamos este lisado para cultivar os fibroblastos humanos e verificamos a dose de irradiação suficiente para inibir sua duplicação. Queratinócitos humanos foram cultivados nestas camadas de sustentação, em meio de cultura suplementado com o lisado. Com os resultados obtidos concluímos que o lisado de plaquetas a 10% promoveu uma melhor adesão e proliferação dos fibroblastos humanos e em todas as doses testadas (60 a 300 Gy), estes tiveram as suas atividades mitóticas inativadas pela radiação ionizante, sendo que as camadas de sustentação obtidas com doses de 70 a 150 Gy foram as que proporcionaram o melhor desenvolvimento dos queratinócitos em meio contendo 2,5% de lisado de plaquetas humanas. Portanto, foi possível padronizar, tanto o cultivo dos fibroblastos humanos, quanto sua inativação para utilização como camada de sustentação na cultura de queratinócitos, de maneira a eliminar os componentes xenobióticos. / For over 30 years, the use of culture medium, enriched with bovine serum, and murines fibroblasts, with the rate of proliferation controlled by irradiation or by share anticarcinogenic drugs, has been playing successfully its role in assisting in the development of keratinocytes in culture, for clinical purposes. However, currently there is a growing concern about the possibility of transmitting prions and animals viruses to transplanted patients. Taking into account this concern, the present work aims to cultivate human fibroblasts in a medium enriched with human platelets lysate and determine the irradiation dose of these cells, for obtaining feeder layer in epidermal cell culture. For carrying out the proposed objective, platelets lysis has standardized, this lysate was used for human fibroblasts cultivation and the irradiation dose enough to inhibit its duplication was evaluated. Human keratinocytes were cultivated in these feeder layers, in culture medium enriched with the lysate. With these results we conclude that the 10% platelets lysate promoted a better adhesion and proliferation of human fibroblasts and in all dose levels tested (60 to 300 Gy), these had their mitotic activity inactivated by ionizing irradiation, being that the feeder layers obtained with doses from 70 to 150 Gy were those that provided the best development of keratinocytes in medium containing 2.5% of human platelet lysate. Therefore, it was possible to standardize both the cultivation of human fibroblasts as its inactivation for use as feeder layer in culture of keratinocytes, so as to eliminate xenobiotics components.

Por mais de 30 anos, a utilização do meio de cultura, enriquecido com soro bovino, e de fibroblastos murinos, com a taxa de proliferação controlada por irradiação ou por ação de drogas anti-cancerígenas, vem desempenhando com sucesso o seu papel de auxiliar no desenvolvimento dos queratinócitos em cultura, para fins clínicos. Porém, atualmente há uma preocupação crescente acerca da possibilidade de transmissão de príons e virose animais, aos pacientes transplantados. Levando em conta esta preocupação, o presente trabalho tem como objetivo cultivar fibroblastos humanos em meio enriquecido com lisado de plaquetas humanas e determinar a dose de irradiação dessas células, para obtenção da camada de sustentação na cultura de células da epiderme. Para realização do objetivo proposto, padronizamos a lise das plaquetas, utilizamos este lisado para cultivar os fibroblastos humanos e verificamos a dose de irradiação suficiente para inibir sua duplicação. Queratinócitos humanos foram cultivados nestas camadas de sustentação, em meio de cultura suplementado com o lisado. Com os resultados obtidos concluímos que o lisado de plaquetas a 10% promoveu uma melhor adesão e proliferação dos fibroblastos humanos e em todas as doses testadas (60 a 300 Gy), estes tiveram as suas atividades mitóticas inativadas pela radiação ionizante, sendo que as camadas de sustentação obtidas com doses de 70 a 150 Gy foram as que proporcionaram o melhor desenvolvimento dos queratinócitos em meio contendo 2,5% de lisado de plaquetas humanas. Portanto, foi possível padronizar, tanto o cultivo dos fibroblastos humanos, quanto sua inativação para utilização como camada de sustentação na cultura de queratinócitos, de maneira a eliminar os componentes xenobióticos. / For over 30 years, the use of culture medium, enriched with bovine serum, and murines fibroblasts, with the rate of proliferation controlled by irradiation or by share anticarcinogenic drugs, has been playing successfully its role in assisting in the development of keratinocytes in culture, for clinical purposes. However, currently there is a growing concern about the possibility of transmitting prions and animals viruses to transplanted patients. Taking into account this concern, the present work aims to cultivate human fibroblasts in a medium enriched with human platelets lysate and determine the irradiation dose of these cells, for obtaining feeder layer in epidermal cell culture. For carrying out the proposed objective, platelets lysis has standardized, this lysate was used for human fibroblasts cultivation and the irradiation dose enough to inhibit its duplication was evaluated. Human keratinocytes were cultivated in these feeder layers, in culture medium enriched with the lysate. With these results we conclude that the 10% platelets lysate promoted a better adhesion and proliferation of human fibroblasts and in all dose levels tested (60 to 300 Gy), these had their mitotic activity inactivated by ionizing irradiation, being that the feeder layers obtained with doses from 70 to 150 Gy were those that provided the best development of keratinocytes in medium containing 2.5% of human platelet lysate. Therefore, it was possible to standardize both the cultivation of human fibroblasts as its inactivation for use as feeder layer in culture of keratinocytes, so as to eliminate xenobiotics components.

Master of Science / Department of Agricultural Economics / Ted C. Schroeder / With volatile cattle markets, comes substantial amounts of price risk for all parties involved in the industry. Hedging with futures markets to mitigate risk is a common practice performed by commercial producers. For this to be an effective risk management tool, the futures contract must function correctly by accurately representing the price and quality of the underlying product. Often times, commodity futures contracts are settled by physical delivery. However, two livestock contracts transitioned to a cash settled index, feeder cattle in 1986 and lean hogs in 1997, to enhance the performance of the contract and promote participation by commercial users. Eliminating high delivery costs, reducing any issues with the grading process when the product is delivered, and portraying a truer commercial value, are some of the benefits of a cash settlement index. There has been some speculation that dates back to the 1980’s regarding whether the live cattle futures contract should switch to cash settlement rather than physical delivery. This study was done to measure the impact the change to cash settlement had on the hedging ability of the feeder cattle futures contract. Even though the feeder cattle contract represents a different sector of the industry, the results still provide some insight as to whether cash settlement can be advantageous for a futures contract. The ability to forecast basis is critical when hedging with futures to manage risk. The magnitude of basis prediction error (BPE), or the difference between expected basis and actual basis, is a common method used to measure the hedging ability of a futures contract. This procedure was utilized to analyze the effects the change to cash settlement had on BPE in six different regions: Kansas, Missouri, Nebraska, North/South Dakota, Oklahoma, and Texas. Expected basis was calculated using a two, three, and four year historical average technique for each respective week to contract expiration. Other market factors were also included in the models to ensure the cash settlement adjustment was not the sole reason for BPE variations over time. To estimate the impact the different elements have on basis predictability, Ordinary Least Squares regression was used for each of the three stacked models. For the two-year historical basis prediction error model, Kansas was the only area with a statistically significant value indicating cash settlement reduced BPE by $0.18. Three states, Kansas (-$0.24/cwt.), Missouri (-$0.17/cwt.), and Texas (-$0.16/cwt.), showed a statistically significant decrease in BPE due to cash settlement for the three-year historical basis prediction error model. Also, the coefficient for Oklahoma was just slightly above the statistically significant level. However, the four-year model had moderately different results. The estimate for Kansas was statistically significant at -$0.18/cwt. meaning cash settlement reduced BPE, while the Dakotas region actually showed a statistically significant increase in BPE by $0.18/cwt. This research provides evidence that cash settlement can improve the basis predictability of a futures contract depending on the region and technique used to calculate expected basis.

Traditional factors known to affect feeder cattle prices, such as corn prices, have been questioned recently given the volatile nature of agricultural markets and some recent research findings. This work utilizes two very current and unique datasets to examine feeder cattle pricing relationships from Kentucky internet auctions and Certified Preconditioned for Health (CPH) sales. In addition to examining traditional pricing factors, factors that affect feeder cattle basis were also examined. Basis questions are of great interest in the southeast as transportation costs to major cattle feeding areas have been impacted by rising fuel prices and increased market volatility. Finally, price premiums were examined for cattle selling as age and source verified and natural. Results suggested that traditional factors were still found to influence feeder cattle prices, with some evidence that the magnitude of these effects may be smaller. Basis factors were found to be relevant; specifically fuel price was found to have a negative effect on basis in internet sales. This finding was also consistent with weaker basis in areas further away from the Midwest. Finally, premiums for age and source verification were moderate, roughly $11 per head for age and source verified calves, $17 per head for natural calves, and about $32 per head for cattle with both attributes.

Master of Science / Department of Agricultural Economics / Ted Schroeder / Feeder cattle are placed into feedlots at varying weights. This placement weight is the result of procurement decisions by cattle feeders and of marketing decisions by cow/calf and stocker/backgrounder producers. Increased understanding of the behavior of these markets can help both buyers and sellers of feeder cattle make these decisions. Past research has used linear or quadratic variables or interaction variables in order to model the effects of weight on price. This study instead divides the market for feeder cattle into ten distinct subsets which are evaluated independently. The feeder cattle market for four major cattle feeding states in the Southern Great Plains (Nebraska, Kansas, Oklahoma and Texas) was divided into ten subsets, five in each gender. Each of these represent feeder cattle coming to market in a 50 pound weight range, centered upon 525, 625, 725, 825 and 925 pounds. Each of these subsets was analyzed using seven independent variables selected based upon previous research and economic rationale. These variables were the live futures price, previous feedlot returns, feeder cattle inventory, interest rate, feedlot capacity utilization, cost of gain and pasture conditions. The data for these variables were collected from public sources, aggregated into monthly observations and differenced to correct for nonstationarity. Analysis was conducted using ordinary least squares regressions. Results are reported and trends between weight classes discussed along with their implications. Findings support that feeder cattle of different weights are not perfect substitutes and that market and production factors do not influence all weights of feeder cattle the same. In fact, factors which positively and negatively affect feeder cattle price seem to signal that demand for, or in the case of pasture supply of, feeder cattle of a particular weight has changed and that placement price-weight relationships will adjust accordingly.

Master of Science / Department of Animal Sciences and Industry / Robert D. Goodband / A total of 5,480 pigs involving 10 experiments were conducted. Experiment 1 evaluated 3 feeder gap settings: 1.27, 1.91, or 2.54 cm, while Exp. 2 evaluated the effects of feeder trough space (4.45 vs. 8.9 cm/pig) and minimum feeder gap opening of 1.27 vs. 2.54 cm. In Exp. 1, pigs fed with increasing feeder gap had decreased (linear; P < 0.03) G:F due to increased (linear; P <0.02) ADFI. In Exp. 2, there was a tendency (P = 0.08) for increased ADG as feeder trough space increased from 4.45 to 8.9 cm/pig. Pigs fed with the wide feeder gap setting had increased (P < 0.01) ADFI and decreased (P < 0.01) G:F compared to pigs with the narrow feeder gap setting. Experiments 3 and 4 were conducted to determine the effects of diet form (meal vs. pellet) and feeder design (conventional dry vs. wet-dry) on finisher pig performance. In Exp. 3, pigs fed pelleted diets or via a wet-dry feeder had greater (P < 0.07 and 0.01, respectively) ADG then those fed meal diets or with a dry feeder. Diet × feeder interactions (P < 0.02) were observed for G:F. When pelleted diets were presented in dry feeders, G:F decreased, while no difference in G:F was observed between meal and pelleted diets presented in wet-dry feeders. In Exp. 4, pigs fed with wet-dry feeders had increased (P < 0.02) ADG and ADFI compared to those with dry feeders, while pigs presented pelleted diets had improved (P = 0.05) G:F compared to those presented meal diets. Experiments 5 to 9 were conducted to determine the effects of porcine intestinal mucosa products, PEP2+, Peptone 50, and PEP-NS, on the growth performance of nursery pigs. In Exp. 5, pigs fed increasing PEP2 had increased (quadratic; P < 0.02) overall ADG, ADFI, and G:F with the greatest response observed at 4% PEP2. In Exp. 6, pigs fed PEP2 had improved (P < 0.03) G:F compared to pigs fed select menhaden fish meal (SMFM) and increasing PEP2 improved (quadratic; P < 0.04) G:F with the greatest improvement seen when diets contained 4% PEP2. In Exp. 7 pigs fed PEP2+, Peptone 50 and PEP-NS had increased (P < 0.05) ADG and ADFI compared to pigs fed a negative control diet. In Exp. 8, pigs fed diets containing 6% SMFM, PEP2+, or PEP-NS had improved (P < 0.05) ADG and ADFI compared to pigs fed the negative control or 6% Peptone 50. In Exp. 9, pigs fed increasing PEP-NS had improved (quadratic; P < 0.01) ADG and G:F, with the greatest improvement observed in pigs fed 6% PEP-NS. Experiment 10 evaluated the effects of Liquitein and PCV2/M. hyo vaccine regimen on the growth performance of weanling pigs. Overall, there were no effects of Liquitein on growth performance and vaccinated pigs had decreased (P < 0.01) ADG and ADFI compared to non-vaccinated pigs.

Detta examensarbete behandlar analys, simulering och dimensionering en drivaxel till en baltransportör för returfiber vid SCA Munksund. Transportören drivs i dagsläget av två hydraulmotorer försedda med varsin 3-stegs planetväxellåda, en på varje sida av drivaxeln för transportbandet. Växellådorna skall bytas ut och en driftsäker, kostnadseffektiv ersättningslösning efterfrågas. I studien kartläggs dimensionerande belastningar och en belastningsmodell upprättas för kedjetransportören. Befintlig axel beräknas både analytiskt och simuleras i Solidworks Simulation. Axeln, inklusive monterade detaljer som rullager, kedjehjul och kilar utreds med avseende på hållfasthet i fyra lastfall: Enkeldrift och dubbeldrift, med nominell belastning respektive maximal belastning. Studien konstaterar att befintlig axel håller i nuvarande uppställning men bör inte modifieras för att passa en ny växellåda, stor risk för plasticering av axeln föreligger. Befintlig axel håller inte för enkeldrift, spänningar i axelns stål överskrider sträckgränsen i a xelförbandet mot v äxellådan och lagerläget för mittersta rullagret. Förslag på en ny axel har tagits fram. Beräkningsunderlag, simuleringar och tillverkningsritning redovisas. Den nya axeln tillverkas i SS2541 som har sträckgränsen 700 MPa och med förbättringar i hålkäler främst vid diameterändringar kan befintliga lagringar återanvändas. En kostnadsuppskattning bifogas för kostnader relaterade till axelbytet.

abstract: Until late 1970’s the primary focus in power system modeling has been largely directed towards power system generation and transmission. Over the years, the importance of load modeling grew and having an accurate representation of load played an important role in the planning and operation studies. With an emphasis on tackling the topic of load modeling, this thesis presents the following intermediary steps in developing accurate load models: 1. Synthesis of a three-phase standard feeder and load model using the measured voltages and currents, for events such as faults and feeder pickup cases, obtained at the head of the feeder. 2. Investigated the impact of the synthesized standard feeder and load model on the sub-transmission system for a feeder pick-up case. In the first phase of this project, a standard feeder and load model had been synthesized by capturing the current transients when three-phase voltage measurements (obtained from a local electric utility) are played-in as input to the synthesized model. The comparison between the measured currents and the simulated currents obtained using an electromagnetic transient analysis software (PSCAD) are made at the head of the designed feeder. The synthesized load model has a load composition which includes impedance loads, single-phase induction motor loads and three-phase induction motor loads. The parameters of the motor models are adjusted to obtain a good correspondence between measured three-phase currents and simulated current responses at the head of the feeder when subjected to events under which measurements were obtained on the feeder. These events include faults which occurred upstream of the feeder at a higher voltage level and a feeder pickup event that occurred downstream from the head of the feeder. Two different load compositions have been obtained for this feeder and load model depending on the types of load present in the surrounding area (residential or industrial/commercial). The second phase of this project examines the impact of the feeder pick-up event on the 69 kV sub-transmission system using the obtained standard feeder and load model. Using the 69 kV network data obtained from a local utility, a sub-transmission network has been built in PSCAD. The main difference between the first and second phase of this project is that no measurements are played-in to the model in the latter case. Instead, the feeder pick-up event at a particular substation is simulated using the reduced equivalent of the 69 kV sub-transmission circuit together with the synthesized three-phase models of the feeder and the loads obtained in the first phase of the project. Using this analysis, it is observed that a good correspondence between the PSCAD simulated values of both three-phase voltages and currents with their corresponding measured responses at the substation is achieved. / Dissertation/Thesis / Masters Thesis Electrical Engineering 2018