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Lateral Resistance of Piles Near Vertical MSE Abutment Walls at Provo Center StreetNelson, Kent R. 18 March 2013 (has links) (PDF)
Full scale lateral load tests were performed on four piles located at various distances behind MSE walls. Three of the four test piles were production piles used to support bridges, and the other pile a production pile used as part of the bridge abutment. The objective of the testing was to determine the effect of spacing from the wall on the lateral resistance of the piles and on the force resisted by the MSE reinforcement. Lateral load-displacement curves were developed for pile at various spacing and with various reinforcement ratio (reinforcement length, L divided by wall height, H). The force in the reinforcement was measured using strain gauges. Lateral load analyses were performed to determine the minimum spacing required to eliminate any effect of the wall on the pile resistance (p-multiplier of 1) and the reduction in soil resistance at closer spacings (p-multiplier less than 1). With the addition of the data fro Price (2012) tentative curves have been developed showing p-multiplier vs. normalized spacing behind wall for a length to height ratio of 1.6, 1.2, and 1.1. The data suggest that with a L/H ratio of 1.6, a p-multiplier of 1 can be used when the normalized distance from the back face of the MSE wall to the center of the pile is at least 3.8 pile diameters. When the L/H ratio decreases to 1.2 and 1.1 a p-multiplier of 1 can be used when the pile is at least 4.5 and 5.2 pile diameters behind the wall respectively. For smaller spacings, the p-multipliers decreased essentially linearly with normalized distance from the wall. A plot showing the increased load in the reinforcement as a function of distance from the pile has been developed. The data in the plot is normalized to the maximum lateral load and to the spacing from the wall to the pile. The best fit curve is capped at a normalized tensile force of approximately 0.12. The data show that the increase in tensile force on the reinforcement when a lateral load is applied to the piles decreases exponentially as the normalized distance from the pile increases. The plot is limited to the conditions tested, i.e. for the reinforcement in the upper 3 ft. of the wall with L/H values at 1.2.
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An Investigation Of The Relationship Between Visual Effects And Object Identification Using Eye-trackingRosch, Jonathan 01 January 2012 (has links)
The visual content represented on information displays used in training environments prescribe display attributes as brightness, color, contrast, and motion blur, but considerations regarding cognitive processes corresponding to these visual features require further attention in order to optimize the display for training applications. This dissertation describes an empirical study with which information display features, specifically color and motion blur reduction, were investigated to assess their impact in a training scenario involving visual search and threat detection. Presented in this document is a review of the theory and literature describing display technology, its applications to training, and how eye-tracking systems can be used to objectively measure cognitive activity. The experiment required participants to complete a threat identification task, while altering the displays settings beforehand, to assess the utility of the display capabilities. The data obtained led to the conclusion that motion blur had a stronger impact on perceptual load than the addition of color. The increased perceptual load resulted in approximately 8- 10% longer fixation durations for all display conditions and a similar decrease in the number of saccades, but only when motion blur reduction was used. No differences were found in terms of threat location or threat identification accuracy, so it was concluded that the effects of perceptual load were independent of germane cognitive load.
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Load Estimation For Electric Power Distribution NetworksEyisi, Chiebuka 01 January 2013 (has links)
In electric power distribution systems, the major determinant in electricity supply strategy is the quantity of demand. Customers need to be accurately represented using updated nodal load information as a requirement for efficient control and operation of the distribution network. In Distribution Load Estimation (DLE), two major categories of data are utilized: historical data and direct real-time measured data. In this thesis, a comprehensive survey on the state-of-the-art methods for estimating loads in distribution networks is presented. Then, a novel method for representing historical data in the form of Representative Load Curves (RLCs) for use in realtime DLE is also described. Adaptive Neuro-Fuzzy Inference Systems (ANFIS) is used in this regard to determine RLCs. An RLC is a curve that represents the behavior of the load during a specified time span; typically daily, weekly or monthly based on historical data. Although RLCs provide insight about the variation of load, it is not accurate enough for estimating real-time load. This therefore, should be used along with real-time measurements to estimate the load more accurately. It is notable that more accurate RLCs lead to better real-time load estimation in distribution networks. This thesis addresses the need to obtain accurate RLCs to assist in the decision-making process pertaining to Radial Distribution Networks (RDNs).This thesis proposes a method based on Adaptive Neuro-Fuzzy Inference Systems (ANFIS) architecture to estimate the RLCs for Distribution Networks. The performance of the method is demonstrated and simulated, on a test 11kV Radial Distribution Network using the MATLAB software. The Mean Absolute Percent Error (MAPE) criterion is used to justify the accuracy of the RLCs.
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An Electrical Mine Monitoring System Utilizing the IEC 61850 StandardMazur, David Christopher 14 November 2013 (has links)
Motor control assets are foundational elements in many industrial operations. In the mining industry, these assets primarily consist of motor control centers and drives, which are available with a comprehensive assortment of control and monitoring devices. Various intelligent electronic devices (IEDs) are now used to prevent machine damage and downtime. As motor control devices have advanced in technology, so too have the IEDs that protect them. These advances have resulted in new standards, such as IEC 61850, that have embedded intelligence and a standard set of communication schemes by which IEDs can share information in a peer-to-peer or one-to-many fashion.
This dissertation investigated the steps involved in interfacing IEDs to a mining process control network via the use of the IEC 61850 standard. As a result of this study, several key technological advancements were made including the development of (i) vendor independent system to communicate with IEDs in a mining environment over IEC 61850, (ii) command and control methods for communication based assisted automation of IEDs for mining firms, (iii) effective solutions to incorporate electrical distribution data in the process control system, (iv) enhanced safety platforms through remote operation of IEDs, (v) standard visualization faceplate graphics for HMI operators with enhanced security, and (vi) new methods for time stamped dataflow to be correctly inserted into a process historian for 'true' Sequence of Events Records. / Ph. D.
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Diferences in cognitve load between virtual driving in VR and on regular screensErlandsson, Emil January 2022 (has links)
A interstep between a regular car and a fully self-driving car is a teleoperated car, where the driver controls the car remotely in situations that the self-driving AI isn't equipped to handle. The cognitive load of regular driving is known, and how long it's safe to drive without taking a rest, but it has not been that well explored when it comes to teleoperated driving. This paper examines which screen set-up would be preferable for the operator to use, comparing the cognitive load while using a driving simulator on a conventional computer screen and a head mounted display. The data that was able to be analyzed points to there not being any noticeable difference between the two in terms of cognitive load, but the participants noted the HMD has several advantages over the conventional screen. Despite this, the majority of the participants preferred the conventional screen due to cybersickness and discomfort from the HMD. / Ett mellansteg mellan en vanlig bil och en helt självkörande bil är en fjärrstyrd bil, där föraren fjärrstyr bilen i situationer som den självkörande AIn inte kan klara av. Vi vet hur stor den mentala belastningen är när det gäller vanlig bilkörning, och vi vet hur länge det är säkert att köra utan att behöva ta rast, men när det gäller fjärrstyrda bilar har detta inte undersökts så mycket. Den här rapporten undersöker vilken form av skärm som skulle vara att föredra att använda, genom att jämföra den mentala belastningen mellan en vanlig datorskärm och VR glasögon när man använder en bilsimulator. Resultatet pekar på att det inte var någon märkbar skillnad mellan de två alternativen när det gäller mental belastning, men deltagarna noterade att VR glasögonen hade flera fördelar över den vanliga datorskärmen. Trots detta så föredrog majoriteten av deltagarna att använda den vanliga skärmen då VR glasögonen gav dem åksjuka och var obekväm.
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Chronic stress and conservation: Applying allostatic load to lemurs in human care and native rangesSeeley, Kathryn E. January 2022 (has links)
No description available.
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Transportation of Trace Metals and Major Elements in the Ottawa River, Northwest OhioBissell, Corrina 18 July 2012 (has links)
No description available.
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Investigation into Biomechanical Response and Health Consequences of Military Rucksack Design for Female SoldiersGrawe, Sarah Koop 16 September 2014 (has links)
No description available.
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Vokabulärundervisning i engelska på högstadiet och gymnasiet : Fem lärares syn på undervisning av vokabulär. / English vocabulary in the Swedish lower and upper secondary school : Five teachers' views on how to teach vocabularyFromheden, Katarina Hannah Ingela, Gustavsson Svedelius, Jimmy January 2023 (has links)
The purpose of this qualitative study is to compare five teachers’ beliefs about their students’ learning of vocabulary and compare that with current theories and recommended practices in the field. The method for collecting data was semi-structured interviews with teachers who teach English in both lower secondary and upper secondary schools in Sweden. The data from these interviews were then analyzed by way of thematic analysis. The results were then compared with previous research in the field of vocabulary learning drawing on studies and works of researchers such as Stuart Webb and Paul Nation among others. The results reveal a lot of similarities with the latest research on vocabulary learning. The findings of this study also indicate some differences between teacher beliefs and research. Apart from research done in the field of vocabulary learning this study has also taken the proven experience of the teachers into account. Since this study is of a qualitative kind, these results cannot be generalized in regard to Swedish teachers of English as a group but rather what some of them portray when talking on the topic of vocabulary.
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Design of Miniature Three-Phase Dump Load ModelSalisbury, Tiffany, Akram, Muhammad Arsal January 2022 (has links)
In hydropower plants, a local load, also known as a dump load, could be installed to balance theelectrical grid by consuming excessive power. This enhances the dam safety. A design for asmall-scaled three-phase dump load is presented in this thesis. The designed model is built andevaluated through simulations and experiments. The results show that the system is purelyresistive. The per phase resistance of the model can be calculated with geometrical analysis ofthe design.
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