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Difference in Internal and External Workloads Between Non-Injured and Injured Groups in Collegiate Female Soccer PlayersIshida, Ai, Beaumont, Joshua S. 01 January 2020 (has links)
This is an open access article under CC BY license (https://creativecommons.org/licenses/by/4.0/) Background: Effects of internal and external workloads (IL, EL) on lower limb soft-tissue injuries (LLSTI) risk in male soccer players has been described, the relationships remain unclear in collegiate female (soccer players. Objective: The purpose was to examine the mean difference in IL and EL in LLSTI between non-injured and injured groups (N-IG and IG). Method: 20 collegiate female soccer players (age: 19.2±1.2years; height: 168.2±7.3cm; body mass: 41.0±17.9kg) were included for 14 week competitive season. IL included average heart rate (Avg-HR) and high heart rate zone. EL included total distance, average speed (Avg-Spd), and high-speed running distance. Injuries were counted if (a) they were LLSTI and muscular/ ligamentous strains or tears and tendon problems, and (b) the players missed more than one match or training session. Acute (7-day simple average) and chronic (21-day simple average) IL and EL were calculated in the IG while the mean of acute (7-day) and chronic (21-day) IL and EL were computed in the NIG. Acute Chronic Workload Ratio (ACWR) was calculated as the ratio of acute and chronic IL and EL. Results: Seven LLSTI occurred over 14 weeks. The acute Avg-HR and ACWR of Avg-Spd were significantly higher in the IG than the N-IG (p=0.001 and 0.024). IL and EL in the IG were placed below or above the mean of the N-IG. Conclusion: LLSTI might occur at high and low workloads in collegiate female soccer players. This may support the use of micro-technology to monitor workload based on individual player’s threshold to reduce LLSTI.
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Decision modeling to compare effectiveness of intervention strategies for infected cardiac implantable electronic devicesPowers-Fletcher, Margaret 02 June 2023 (has links)
No description available.
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Implementation of an IEC 61850 Sampled Values Based Line Protection IED with a New Transients-Based Hybrid Protection AlgorithmKapuge Kariyawasam Mudalige, Sachintha Kariyawasam 26 May 2016 (has links)
Over the course of the last decade, IEC 61850 has become the leading standard for electrical substation automation the world over. This thesis presents the work done towards implementing an IEC 61850 sampled values based line protection Intelligent Electronics Device (IED) on a desktop computer. This IED is capable of subscribing, decoding and processing the sampled values published by a source to be used in line protection algorithms.
The novel hybrid line protection algorithm implemented in the IED combines a distance protection scheme with a transients-based unit protection method that uses sampled values complying with IEC 61850-9-2-LE. Application of the line protection relay for protecting a series compensated transmission line was examined using hardware-in-the-loop simulations. Results indicate that (i) the implemented algorithms are robust and reliable, and (ii) the class of transients based protection algorithms examined in this thesis can be successfully implemented with IEC 61850 sampled values. / October 2016
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Synchrophasor Measurement Using Substation Intelligent Electronic Devices: Algorithms and Test MethodologyRen, Jinfeng 2011 December 1900 (has links)
This dissertation studies the performance of synchrophasor measurement obtained using substation Intelligent Electronic Devices (IEDs) and proposes new algorithms and test methodology to improve and verify their performance when used in power system applications.
To improve the dynamic performance when exposed to sinusoidal waveform distortions, such as modulation, frequency drift, abrupt change in magnitude, etc, an adaptive approach for accurately estimating phasors while eliminating the effect of various transient disturbances on voltages and currents is proposed. The algorithm pre-analyzes the waveform spanning the window of observation to identify and localize the discontinuities which affect the accuracy of phasor computation. A quadratic polynomial signal model is used to improve the accuracy of phasor estimates during power oscillations. Extensive experimental results demonstrate the advantages. This algorithm can also be used as reference algorithm for testing the performance of the devices extracting synchronized phasor measurements.
A novel approach for estimating the phasor parameters, namely frequency, magnitude and angle in real time based on a newly constructed recursive wavelet transform is developed. This algorithm is capable of estimating the phasor parameters in a quarter cycle of an input signal. It features fast response and achieves high accuracy over a wide range of frequency deviations. The signal sampling rate and data window size can be selected to meet desirable application requirements, such as fast response, high accuracy and low computational burden. In addition, an approach for eliminating a decaying DC component, which has significant impact on estimating phasors, is proposed using recursive wavelet transform.
This dissertation develops test methodology and tools for evaluating the conformance to standard-define performance for synchrophasor measurements. An interleaving technique applied on output phasors can equivalently increase the reporting rate and can precisely depict the transient behavior of a synchrophasor unit under the step input. A reference phasor estimator is developed and implemented. Various types of Phasor Measurement Units (PMUs) and PMU-enabled IEDs (Intelligent Electronic Devices) and time synchronization options have been tested against the standards using the proposed algorithm. Test results demonstrate the effectiveness and advantages.
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Mise au point d’un outil de mesure de la cinématique du genou en contexte clinique / Development of a device for clinical kinematic evaluation of the kneeTesta, Rodolphe 25 November 2011 (has links)
Ce travail rapporte le développement et la validation d’un système de mesure pour l’étude cinématique des rotations du genou en 3 dimensions. Pour cela, nous avons dans un premier temps étudié in‐vitro les avantages apportés par un système de mesure de référence par rapport à l’évaluation du clinicien. Dans un second temps, nous avons développé un outil de mesure optoélectronique utilisable dans un contexte clinique. Nous avons réalisé une étude de reproductibilité de ce système pour des mesures de rotation interne‐externe en charge sur une série de sujets sains. Enfin, nous avons utilisé le système en condition réelle lors d’une étude clinique de revue à 2 ans de recul. 16 sujets opérés d’une rupture partielle du LCA ont été revus lors d’une consultation. Des mesures de rotation interne‐externe du genou en charge ainsi que des mesures de proprioception ont été réalisées. / The purpose of this work was to develop and to validate a new device for clinical 3D rotational kinematic evaluation of the knee. With this aim in view, we demonstrated in‐vitro the advantages of using a device for clinical evaluation of the knee. After, we developed a clinical opto‐electronic device. We validated it with a protocol for knee examination during an active weight bearing test of rotational laxity on healthy subjects. Last, the device was used in actual conditions for a clinical study. 16 patients were examined 2 years after an ACL partial reconstruction. Weight bearing tests of rotational laxity and proprioception evaluation were performed on the patients.
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Konstrukce GPS přístroje / Construction of The GPS deviceHlaváč, Libor January 2010 (has links)
The goal of this thesis is a complete design and realization of a device that is able to communicate with GPS module iTrax300 and display the coordinates received from the module. The thesis deals with the GPS, localization principles and the standard communication protocol for navigation systems - the NMEA 0183 protocol. Futhermore it is dealing with the particular steps in the realization of the engineered device (from the specification of requirements at the beginning to the testing of its functionality in the end). The GPS coordinates, the Coordinated Universal Time (UTC), the date, the altitude and the speed on the ground can be displayed. There is also a possibility to put in any coordinates, the direction and the distance to the point are displayed afterwards. The device enables the track storage in the memory as well. The track is viewable while connecting the device and the PC through the USB interface.
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Substituted Azadipyrromethene-based Non-fullerene Acceptors for Organic Electronic Applications: A Structure-Property StudyZhao, Muyuan 26 August 2022 (has links)
No description available.
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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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Planar Packaging and Electrical Characterization of High Temperature SiC Power Electronic DevicesYue , Naili 31 December 2008 (has links)
This thesis examines the packaging of high-temperature SiC power electronic devices. Current-voltage measurements were conducted on as-received and packaged SiC power devices. The planar structure was introduced and developed as a substitution for traditional wire-bonding vertical structure. The planar structure was applied to a high temperature (>250oC) SiC power device. Based on the current-voltage (I-V) measurements, the packaging structures were improved, materials were selected, and processes were tightly controlled.
This study applies two types of planar structures, the direct bond and the bump bond, to the high-temperature packaging of high-temperature SiC diode. A drop in the reverse breakdown voltage was discovered in the packaging using a direct bond. The root cause for the drop in the breakdown voltage was identified and corrective solutions were evaluated. A few effective methods were suggested for solving the breakdown issue. The forward I-V curve of the planar packaging using direct bond showed excellent results due to the excellent electrical and thermal properties of sintered nanosilver. The packaging using a bump bond as an improved structure was processed and proved to possess desirable forward and reverse I-V behavior. The cross-sections of both planar structures were inspected.
High-temperature packaging materials, including nano-silver paste, high-lead solder ball and paste, adhesive epoxy, and encapsulant, were introduced and evaluated. The processes such as stencil printing, low-temperature sintering, solder reflowing, epoxy curing, sputtering deposition, electroplating, and patterning of direct-bond copper (DBC) were tightly controlled to ensure high-quality packaging with improved performance.
Finally, the planar packaging of the high temperature power device was evaluated and summarized, and the future work was recommended. / Master of Science
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Fabrication of Large-Scale and Thickness-Modulated Two-Dimensional Transition Metal Dichalcogenides [2D TMDs] NanolayersPark, Juhong 05 1900 (has links)
This thesis describes the fabrication and characterization of two-dimensional transition dichalcogenides (2D TMDs) nanolayers for various applications in electronic and opto-electronic devices applications. In Chapter 1, crystal and optical structure of TMDs materials are introduced. Many TMDs materials reveal three structure polytypes (1T, 2H, and 3R). The important electronic properties are determined by the crystal structure of TMDs; thus, the information of crystal structure is explained. In addition, the detailed information of photon vibration and optical band gap structure from single-layer to bulk TMDs materials are introduced in this chapter. In Chapter 2, detailed information of physical properties and synthesis techniques for molybdenum disulfide (MoS2), tungsten disulfide (WS2), and molybdenum ditelluride (MoTe2) nanolayers are explained. The three representative crystal structures are trigonal prismatic (hexagonal, H), octahedral (tetragonal, T), and distorted structure (Tʹ). At room temperature, the stable structure of MoS2 and WS2 is semiconducting 2H phase, and MoTe2 can reveal both 2H (semiconducting phase) and 1Tʹ (semi-metallic phase) phases determined by the existence of strains. In addition, the pros and cons of the synthesis techniques for nanolayers are discussed. In Chapter 3, the topic of synthesized large-scale MoS2, WS2, and MoTe2 films is considered. For MoS2 and WS2 films, the layer thickness is modulated from single-layer to multi-layers. The few-layer MoTe2 film is synthesized with two different phases (2H or 1Tʹ). The all TMDs films are fabricated using two-step chemical vapor deposition (CVD) method. The analyses of atomic force microscopy (AFM), high-resolution transmission electron microscopy (HRTEM), photoluminescence (PL), and Raman spectroscopy confirm that the synthesis of high crystalline MoS2, WS2, and MoTe2 films are successful. The electronic properties of both MoS2 and WS2 exhibit a p-type conduction with relatively high field effect mobility and current on/off ratio. In Chapter 4, vertically-stacked few-layer MoS2/WS2 heterostructures on SiO2/Si and flexible polyethylene terephthalate (PET) substrates is presented. Detailed structural characterizations by Raman spectroscopy and high-resolution/scanning transmission electron microscopy (HRTEM/STEM) show the structural integrity of two distinct 2D TMD layers with atomically sharp van der Waals (vdW) heterointerfaces. Electrical transport measurements of the MoS2/WS2 heterostructure reveal diode-like behavior with current on/off ratio of ~ 104. In Chapter 5, optically uniform and scalable single-layer Mo1-xWxS2 alloys are synthesized by a two-step CVD method followed by a laser thinning. Post laser treatment is presented for etching of few-layer Mo1-xWxS2 alloys down to single-layer alloys. The optical band gap is controlled from 1.871 to 1.971 eV with the variation in the tungsten (W) content, x = 0 to 1. PL and Raman mapping analyses confirm that the laser-thinning of the Mo1-xWxS2 alloys is a self-limiting process caused via heat dissipation to SiO2/Si substrate, resulting in fabrication of spatially uniform single-layer Mo1-xWxS2 alloy films.
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