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Vliv predátora na ostražitost sýkor navštěvujících krmítko / The effect of a predator occurrence on vigilance of tits visiting the winter feederTichá, Irena January 2011 (has links)
This thesis evaluates the vigilance parameters of two species of tits affected by the presence of a predator in wintertime. During preferential experiments, tits have had a choice of two feeders in the vicinity of the installed dummy predator. For that purpose was used a dummy sparrowhawk, incomplete or occluded sparrowhawk torsos, and harmless pigeon. It is known that the tits are able to recognize dangerousness presented by the dummy, and according to expected risk dare to visit one of the feeders. It leads to a question whether the tits are somehow influenced by the presence of the dummies, and if so, how specifically are they influenced. It turned out, that the tits in presence of a dangerous dummy significantly increased their vigilance. Both observed species at the feeders behave oppositely. Behaviour of all the birds at the feeder is also affected by their total count at the precise moment and by the presence of a dummy at the other feeder.
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Feeder Performance Analysis with Distributed AlgorithmWang, Lingyun 26 May 2011 (has links)
How to evaluate the performance of an electric power distribution system unambiguously and quantitatively is not easy. How to accurately measure the efficiency of it for a whole year, using real time hour-by-hour Locational Marginal Price data, is difficult. How to utilize distributed computing technology to accomplish these tasks with a timely fashion is challenging.
This thesis addresses the issues mentioned above, by investigating feeder performance analysis of electric power distribution systems with distributed algorithm.
Feeder performance analysis computes a modeled circuit's performance over an entire year, listing key circuit performance parameters such as efficiency, loading, losses, cost impact, power factor, three phase imbalance, capacity usage and others, providing detailed operating information for the system, and an overview of the performance of every circuit in the system.
A diakoptics tearing method and Graph Trace Analysis based distributed computing technology is utilized to speed up the calculation. A general distributed computing architecture is established and a distributed computing algorithm is described.
To the best of the author's knowledge, it is the first time that this detailed performance analysis is researched, developed and tested, using a diakoptics based tearing method and Graph Trace Analysis to split the system so that it can be analyzed with distributed computing technology. / Master of Science
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Flexible Solution for an Automatic Assembly CellWakim, Majed January 2022 (has links)
This project is being carried out in collaboration with Parker Hannifin. The main objective of this project is to achieve a simulation of an automatic assembly cell for the assembly of the CRVs in the P70 hydraulic valve assembly line. The robotic cell uses the line layout to perform the assembly. It consists of a robot, an automatic feeder system, a conveyor system, an assembly table, and an aligner stand. The tool used to perform the assembly is a combination of two tools mounted on a multi-tool. The first tool is a vacuum gripper, and the second tool is a drill driver. The time taken by the robot to complete one assembly of a P70 module of three sections, with a size of six CRVs on each side, A and B, is eighty-eight seconds which is faster than the speed of a manual operator. The throughput rate of the assembly cell is forty-one complete assemblies per hour, which equals one hundred and twenty-three sections per hour. This result shows clear improvement comparing it to the manual assembly throughput rate. The minimum time for the automatic feeder system to request a refill is approximately twenty-two and a half minutes. A minimal change is required when a new specification is added to the assembly line.
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Secure Fish Feeder : Automatic secure fish feeder to make sure you do not overfeed your fish / Säker fiskmatareGriffith, Elias, Iljans, Jacob January 2021 (has links)
This project aims to provide fish keepers with a safe and simple way to feed their pets while abroad or in any other situation where they do not have the ability to feed their fish by hand. Overfeeding is an unfortunate albeit common reason for mass death in an otherwise safe and healthy aquarium. While overfeeding to land dwelling pets might have negative health implications, the rapid damage seen in an aquarium is unparalleled in other environments. This is due to the release of ammonia that occurs when excess food (and partially fecal matter) is decomposed. Moderate feedings provide adequate nutrition for the pets, while keeping ammonia production at a level where it can be converted to nitrite and lastly the rather harmless compound nitrate. Most, if not all, feeders on the market today base their feedings solely off of volume, but this can lead to large variations in feeding size, due to variations in air between pellets in the feeding portions. By adding a failsafe with weight, we can fully prevent any chance of overfeeding, and thus ensuring a long and healthy life for our pets. Overall the goals of a safe fish feeder were accomplished, although the weighing was not as accurate as it optimally would have been. / Med det här projektet syftar vi på att tillförse akvarieägare med ett tryggt och enkelt sätt att mata sina fiskar när de är utomlands eller av annan anledning inte har möjlighet att mata för hand. Övermatning är en olycklig men dessvärre vanlig anledning till massdöd i ett annars hälsosamt akvarium. Även om övermatning hos landdjur kan ha ohälsosamma konsekvenser, så är det aldrig lika skadligt på kort sikt som det är i ett akvarium. Det här beror på att överbliven mat (och även till viss del avföring) i en vattenmiljö snabbt omvandlas till ammoniak under förmultning. Lagom stora matningar ger all näring fiskar behöver, medan enbart en halt ammoniak som kan omvandlas till nitrit och därefter det relativt harmlösa nitratet uppstår snabbt nog för att vara ofarligt. De flesta - om än inte alla - fiskmatare på marknaden idag baserar sina portioner på enbart volym. På grund av variationer i mängden luft mellan foder så kan då mängden mat ha stor variation. Genom att lägga till en säkring med vikt, så kan vi helt och hållet motverka all risk för övermatning, och på så vis säkerställa ett långt och hälsosamt liv för våra husdjur. Överlag lyckades vi skapa ensäker fiskmatare, men dessvärre var inte vågen lika noggrann som den optimalt hade varit.
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Effects of Bird Feeder Density on the Behavior and Ecology of a Feeder-Dependent Songbird: Patterns and Implications for Disease TransmissionAberle, Matthew A. 18 September 2018 (has links)
Anthropogenic resource provisioning of wildlife has increasingly been hypothesized to alter pathogen spread. Although bird feeding is the most widespread form of intentional wildlife provisioning, we know relatively little about how the degree of anthropogenic feeding at a site impacts wild birds in ways relevant to disease transmission. We manipulated the density of bird feeders (low versus high) available at otherwise similar sites and tracked the local abundance, body condition (scaled-mass index), feeding behavior, and movement across the landscape in wild house finches (Haemorhous mexicanus), a feeder-dependent species subject to outbreaks of a contagious pathogen commonly spread at feeders. The local abundance of house finches was significantly higher at sites with high feeder density but, surprisingly, finches at high-density feeder sites had poorer body condition than those at low-density sites. Behaviorally, birds at high-density feeder sites had longer average feeding bouts and spent more time per day on feeders than birds at low-density feeder sites. Further, birds first recorded at low-density feeder sites were more likely to move to a neighboring high-density feeder site than vice versa. Overall, because local abundance and time spent on feeders have been linked with the risk of disease outbreaks in this species, effects of bird feeder density on both traits may, in turn, influence disease dynamics in house finches. Our results suggest that heterogeneity in the density of bird feeders can have diverse effects on wild birds, with potential consequences for disease transmission. / Master of Science / Feeding wildlife has increasingly been thought to change the spread of disease. Although bird feeding is the most widespread form of intentional wildlife feeding, we know relatively little about how much human feeding impacts wild birds in ways that affect disease transmission. We changed the density of bird feeders (low versus high) available at otherwise similar areas and tracked the local abundance, body condition, feeding behavior, and movement across the landscape in wild house finches (Haemorhous mexicanus), a feeder-dependent species subject to outbreaks of a infectious disease commonly spread at feeders. The local abundance of house finches was significantly higher at sites with high feeder density but, surprisingly, finches at high-density feeder sites had poorer body condition than those at low-density sites. Behaviorally, birds at high-density feeder sites had longer average bouts on feeders and spent more time per day on feeders than birds at low-density feeder sites. Further, birds first recorded at low-density feeder sites were more likely to move to a neighboring high-density feeder site than vice versa. Overall, because local abundance and time spent on feeders have been linked with the risk of disease outbreaks in this species, effects of bird feeder density on both traits may, in turn, increase disease spread in house finches. Our results suggest that variation in the density of bird feeders can have diverse effects on wild birds, with potential consequences for disease transmission.
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Optimization of Distribution Systems: Transactive Energy and Resilience EnhancementQi, Chensen 21 May 2024 (has links)
The increasing penetration of electric vehicles (EVs) and other distributed energy resources (DERs) offers enhanced flexibility and resilience. During extreme conditions, grid-connected EVs and DERs can provide electricity service and restore critical loads when the utility system is unavailable. On the other hand, during normal operation, these proactive devices can provide ancillary services to alleviate voltage fluctuations and support frequency regulation. In comparison with other DERs, EVs are more flexible in providing ancillary services due to their mobile nature.
However, the proliferation of EVs and DERs also introduces operational challenges to the distribution grid. For instance, EVs primarily fulfill their transportation needs. Uncoordinated charging of a large number of EVs can increase the burden on the distribution system. Due to the limited charging rate and battery size, it is generally impractical for a single EV to directly participate in the ancillary service market. A conventional distribution system is designed for unidirectional flow of electric energy. With the growing installation of DERs on the distribution system, the flow of electric energy is bi-directional and, therefore, there is a higher risk of protection miscoordination due to the fault currents resulting from DERs. With limited communication capability, these undetected protective device (PD) actuations can cause uncertainties and delay the service restoration process.
This dissertation makes contributions to the coordination of EVs and DERs. It introduces four innovative models for EV coordination: 1) A transactive energy (TE) trading mechanism is proposed to coordinate EVs and aggregators. 2) Optimal tools are provided to assist EVs and aggregators in optimal decision making while participating in TE. 3) A charging station model is developed to allow EVs to provide ancillary service aligned with their mobile nature. 4) A utility function model is presented to capture the EV owners' behaviors for providing ancillary services and charging vehicles. Charging stations can estimate the electric energy demand and optimize ancillary service provision to meet their goals. Simulation cases validated that the proposed optimization tools can align EV owners' preferences in providing ancillary service to enhance distribution system operation flexibility.
To enhance the resilience of distribution systems, two novel optimization strategies are presented: 1) An advanced outage management (AOM) is proposed to utilize smart meters and fault indicators (FIs) to identify the most credible outage scenario and fault locations. 2) An advanced feeder restoration (AFR) is developed to provide an optimal restoration strategy to enhance system resilience. The proposed optimization models have been validated with realistic simulation cases. / Doctor of Philosophy / As Electric Vehicles (EVs) and other Distributed Energy Resources (DERs) become more common, they are changing how our distribution systems work. For example, during power outages, grid-connected DERs and EVs can be deployed to sustain essential electricity services such as hospitals and communications. On the other hand, during a normal operating condition, they can help maintain the stability of our electricity systems.
It is a technical challenge to integrate these new EV and DER devices into the existing power grid. For example, EVs are mainly designed for transportation. Their clustered charging patterns can significantly increase the electrical demand if they are not managed properly. Also, the limited battery capacity and charging speed make it difficult for a single vehicle to provide meaningful support to the grid operation.
For the EV management side, this research is concerned with how to better integrate EVs and similar technologies into the power grid. Four key contributions of this dissertation are: 1) Developing a trading mechanism for EVs and aggregators of EVs to exchange energy and ancillary services efficiently; 2) Creating computational technologies to help these entities optimize their decisions while meeting their requirements; 3) Structuring charging station operations that cater to the preferences of EV owners while supporting grid operation; and 4) Modeling EV owners' decision-making to set optimal pricing and service strategies at charging stations. These mechanisms and strategies will allow EV owners to support the power grid while meeting their transportation needs.
Moreover, the study addresses the issue of enhancement of the distribution system's capability to restore services under extreme conditions. It provides an advanced outage management method that utilizes remote monitoring and control technologies, including smart meters and fault indicators, to identify the location of electrical faults and reduce the outage areas. The advanced feeder restoration method determines an optimal strategy to restore the electricity service efficiently while keeping the distribution grid stable.
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Influence of creep feeding on individual consumption characteristics and growth performance of neonatal and weanling pigsSulabo, Rommel Casilda January 1900 (has links)
Doctor of Philosophy / Department of Animal Sciences and Industry / Michael D. Tokach / Five experiments were performed to determine the influence of creep feeding on individual consumption characteristics and growth performance of neonatal and weanling pigs. These evaluated the effects of lactation feed intake and creep feeding (n = 84 litters; Exp. 1), creep feeding duration (n = 54 litters; Exp. 2), creep feeder design and feed accessibility (n = 54 litters; Exp. 3), organoleptic properties of the creep feed (n = 50 litters; Exp. 4) and creep diet complexity (n = 96 litters; Exp. 5). In summary, creep feeding did not affect preweaning gains and weaning weights of pigs weaned at 3 weeks of age. Creep feeding for 18 d did not influence sow performance. However, creep feeding tended to improve litter weaning weights due to improved survivability. Creep feed consumption was related to piglet maturity rather than the induction of creep feeding. In both experimental and field conditions, pigs that consumed creep feed (eaters) had greater post-weaning feed intake and daily gains compared to non-eaters (pigs that did not consume creep feed) and non-creep fed pigs. This led to improvements in pig weight uniformity and reduction of the severity of post-weaning lag. These benefits were achieved regardless of weaning weight, the complexity of the creep diet, and the duration of creep feeding. The proportion of eaters of creep feed in whole litters can be manipulated. Longer duration of creep feeding increased the proportion of eaters. A rotary creep feeder with a hopper created the most eaters with the lowest creep feed disappearance. Creep diet complexity had the greatest effect in increasing the proportion of pigs consuming creep feed. On the other hand, low feed intake of lactating sows and adding feed flavors to the creep feed did not affect creep feed consumption and the proportion of pigs consuming creep feed. Therefore, creep feeding that focuses in encouraging more suckling piglets to eat is beneficial in producing weanling pigs that are better adapted to weaning, which improves post-weaning performance.
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Carbohydrate Oxidation in Fueling Hovering Flight in the Ruby-throated Hummingbird (Archilochus colubris)Chen, Chris Chin Wah 21 November 2012 (has links)
Nectarivorous hummingbirds subsist almost exclusively on a mixture of sucrose, glucose and fructose found in floral nectar. Previous studies have shown that hummingbirds can fuel hovering flight almost exclusively using recently ingested sucrose. However, the relative capacities for the direct utilization of glucose and fructose by hovering hummingbirds remain unknown. 13C-enriched solutions of glucose and fructose were administered separately. Exhaled breath samples were collected using feeder-mask respirometry and sent for subsequent mass spectrometric analysis. I found hovering hummingbirds transition from exclusively oxidizing endogenous fatty acids when fasted, to oxidizing newly ingested carbohydrates when given access to either glucose or fructose solutions. Interestingly, the amount ingested, fractional turnover of stable carbon isotope signatures, amount oxidized, energy expended and proportion of hovering metabolism supported by each hexose, were each similar between glucose and fructose. These results demonstrate hovering hummingbirds’ ability to utilize fructose and glucose equally.
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Carbohydrate Oxidation in Fueling Hovering Flight in the Ruby-throated Hummingbird (Archilochus colubris)Chen, Chris Chin Wah 21 November 2012 (has links)
Nectarivorous hummingbirds subsist almost exclusively on a mixture of sucrose, glucose and fructose found in floral nectar. Previous studies have shown that hummingbirds can fuel hovering flight almost exclusively using recently ingested sucrose. However, the relative capacities for the direct utilization of glucose and fructose by hovering hummingbirds remain unknown. 13C-enriched solutions of glucose and fructose were administered separately. Exhaled breath samples were collected using feeder-mask respirometry and sent for subsequent mass spectrometric analysis. I found hovering hummingbirds transition from exclusively oxidizing endogenous fatty acids when fasted, to oxidizing newly ingested carbohydrates when given access to either glucose or fructose solutions. Interestingly, the amount ingested, fractional turnover of stable carbon isotope signatures, amount oxidized, energy expended and proportion of hovering metabolism supported by each hexose, were each similar between glucose and fructose. These results demonstrate hovering hummingbirds’ ability to utilize fructose and glucose equally.
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Vliv jednotlivých komponent směsných krmných dávek u krmných míchacích vozů (bez vybírací frézy) na přesnost nakládekJENŠÍ, Lukáš January 2016 (has links)
The diploma thesis entitled The effect of individual components of mixed feed rations in the mixer feeder wagon (without a cutter) on the accuracy of loading is divided into two separate parts. In the first (theoretical) part, the issue of livestock together with preparation and distribution of feed with the mixing feeder wagons are analyzed. The second (practical) part of my work is focused on specific selection of a mixing feeder truck, diet components characteristic and way of their loading including evaluation of their loading accuracy. The main objective of the thesis is to specify evaluation of loading accuracy of each component in the mixed feed rations of a mixing feeder wagon in the selected agricultural companies that specialize in milk and meat production.
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