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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
261

Wa-UM-eii : How a Choreographer Can Use Sonification to Communicate With Dancers During Rehearsals / Wa-UM-eii : Hur en koreograf kan använda icke-verbala talakter för att kommunicera med dansare under repetitioner

Fagergren, Emma January 2012 (has links)
A sonification is a nonverbal speech act and might sound like “wa-UM-eii”, or “wooosh!” The purpose of this study was to investigate a choreographer’s use of sonification in dance instructions, to see if there are different types of sonifications and if the use of these might differ with a change in context. Video material capturing the rehearsals of a noted dance company was analyzed using a cognitive ethnography-based approach. Nine different types of sonifications were identified and described according to purpose, and a context-based analysis showed that certain kinds of sonifications occurred more frequently in some contexts than others. The results suggest that sonification used in dance instruction can serve multiple different purposes – the three main purposes described here are these: to communicate the quality of a movement, to facilitate communication between choreographer and dancers, and to coordinate the dancers as a group.
262

Priverstinės sinchronizacijos sistemos matematinio modelio sudarymas ir tyrimas / Working out and investigation of the mathematical model of the forced synchronization system

Simonaitytė, Irena 08 June 2005 (has links)
The mathematical model of the forced synchronization system, composed of four oscillators is investigated. The mathematical model of the system is the matrix differential equation with delayed arguments. The matrix differential equation is solved using method of steps and applying Laplace transform. Using this method and exact solution of the matrix differential equation with delayed arguments was obtained and exact expressions of the elements of the step responses matrix, of the synchronization system are got. On the base of derived formulas the transition processes of the system are investigated.
263

Pulse Synchronization and Timing Recovery in Differential Code-Shifted Reference Impulse-Radio Ultra-Wideband (DCSR IR-UWB) System

Arabi, Tamim 25 April 2013 (has links)
Ultra-wideband (UWB) is a revolutionary radio communication system that utilizes a large portion of the frequency spectrum while maintaining low power levels and high data rates. UWB systems can be used both indoors and outdoors within the power-level masks regulated by the Federal Communications Commission, thus making the technology very versatile. One of the main advantages of UWB is its robustness to multi-path diversity. The technology has attracted the interests of research and industry alike, owing to the possibility of implementing low-power, low-complexity, and low-cost devices. A widely recognized method of transmitting UWB signals is the use of Impulse Radio technology to transmit information. Impulse Radio Ultra-Wideband (IR-UWB) uses repetitive pulses of very short duration, low duty cycle, and low power levels within FCC regulations. One implementation of IR-UWB pulses in non-coherent transmission is the use of Differential Code-Shifted Reference (DCSR) pulses. In this technique, one of the main challenges at the receiver is pulse-level synchronization that times the received pulses at the right moments for accurate pulse detection. This thesis will introduce two design proposals in attempt to achieve the pulse synchronization. The first proposal is based on a fast-switch-controlled integrator circuit, while the second focuses on the use of an active low pass filter and phase-locked loop circuits to achieve proper clock timing. Both proposals will be presented, together with schematics, computer-aided simulations, and lab tests results.
264

Chaotic communication with erbium-doped fiber ring lasers

VanWiggeren, Gregory D. 05 1900 (has links)
No description available.
265

Adaptive phase synchronization techniques for unbalanced and distorted three-phase voltage system

Woinowsky-Krieger, Alexis Unknown Date
No description available.
266

Determination of Requirements for Smooth Operating Mode Transition and Development of a Fast Islanding Detection Technique for Microgrids

Widanagama Arachchige, Lidula Nilakshi 05 July 2012 (has links)
Opportunities for enhancing the security and reliability of power supply as well as the utilization of renewable and efficient energy sources have generated major interest in Microgrids. A microgrid typically consists of interconnected loads, distributed generators (DG) and energy storages, and should be able to operate in parallel with the utility grid or as a power-island. The main focus of this thesis is on the transition between parallel and islanded operation of a microgrid. A literature review on existing microgrids was carried out. Based on the survey, a microgrid test system was implemented on PSCAD/EMTDC simulation program. The microgrid controls essential for the study and a load shedding scheme were designed and implemented. When the microgrid changes from parallel to islanded operation, its controls need to be changed. It was found that delays in microgrid control mode transition can impact the amount of load need to be shed to preserve the frequency stability and the power quality of the islanded microgrid. The importance of fast detection of islanding was therefore highlighted. The IEEE standard 1547.4-2011 recommends application of the existing DG synchronization criteria for microgrid synchronization. The adequacy of these criteria for synchronization of a microgrid with highly unbalanced loading was investigated. It was found that the required criteria can be met with the support of switched capacitors for voltage balancing, and a circuit breaker supervised by a synchro-check relay is sufficient to successfully reconnect an islanded microgrid back to the utility. In order to meet the requirement for fast detection of islanding of microgrids, new islanding detection technique was proposed. In the proposed scheme, Discrete Wavelet Transform was used to extract features from transient current and voltage signals, and then a Decision Tree classifier was employed to distinguish islanding events from other transients. Simulation based tests asserted that the proposed technique has a high reliability and fast response compared to most existing islanding detection methods. Also, the detection time of the proposed method was invariant with the power imbalance in the microgrid, and gave a zero non-detection-zone with any type of generator.
267

Approximate time and temporal uncertainty in parallel and distributed simulation

Loper, Margaret Gaillard Middleton Lucas 12 1900 (has links)
No description available.
268

KENTUCKY'S ADAPTER FOR PARALLEL EXECUTION AND RAPID SYNCHRONIZATION

Mitta, Swetha 01 January 2007 (has links)
As network hardware has become faster, inefficient communication and synchronization mechanisms often have proven to be fast enough but better models are needed in order to support future systems. The aggregate function communication model, and the KAPERS design and implementation presented in this thesis, provide more efficient ways to implement a wide range of higher-level communication and synchronization operations. The main contributions of this work center on a new way to use FPGA-based memory in an aggregate function network (AFN). The basic functions were designed and implemented with modal encoding to create a global memory that allows variable length objects and object addresses. New and enhanced algorithms were written for use with the new AFN architecture. This thesis also details the KAPERS prototype hardware implementation.
269

Seshat : A sync system for Audiobooks and eBooks

Dervisevic, Adnan, Oskarsson, Tobias January 2014 (has links)
In this degree project we present a way to construct a synchronization system that is able to create a timings file, which is the file the system uses to know how to sync the eBook and audiobook, using speech recognition and estimation algorithms. This file is then used by the system to let the user select a sentence and have the audiobook start reading from that sentence, or vice versa. This system can create these files with a mean offset from a manu-ally timed file which is within our expectations for the system. We use estimation algorithms to fill in the blanks where the speech recognition falls short. Speech recognition accuracy is typically between 40-60%, sometimes dipping lower, so there are blanks to fill in. Using basic algebraic principles of calculating velocity we can ex-trapolate the speed of a reader, using the duration of the audiobook as the time and the amount of characters written as the distance. For increased accuracy we derive this value on a per-chapter basis. Using this method we are able to create accurate files, which the user can use to freely sync any location in the book. Our system is designed to work for any book in the world that does not have an audiobook which cuts off between sentences in the audio files. We manually create timings files for four different books with widely varying publishing dates, author styles, reader style and gender to create as wide and representative a testing pool as possible for the project
270

Managing Consistency of Business Process Models across Abstraction Levels

ALMEIDA CASTELO BRANCO, MOISES January 2014 (has links)
Process models support the transition from business requirements to IT implementations. An organization that adopts process modeling often maintain several co-existing models of the same business process. These models target different abstraction levels and stakeholder perspectives. Maintaining consistency among these models has become a major challenge for such an organization. For instance, propagating changes requires identifying tacit correspondences among the models, which may be only in the memories of their original creators or may be lost entirely. Although different tools target specific needs of different roles, we lack appropriate support for checking whether related models maintained by different groups of specialists are still consistent after independent editing. As a result, typical consistency management tasks such as tracing, differencing, comparing, refactoring, merging, conformance checking, change notification, and versioning are frequently done manually, which is time-consuming and error-prone. This thesis presents the Shared Model, a framework designed to improve support for consistency management and impact analysis in process modeling. The framework is designed as a result of a comprehensive industrial study that elicited typical correspondence patterns between Business and IT process models and the meaning of consistency between them. The framework encompasses three major techniques and contributions: 1) matching heuristics to automatically discover complex correspondences patterns among the models, and to maintain traceability among model parts---elements and fragments; 2) a generator of edit operations to compute the difference between process models; 3) a process model synchronizer, capable of consistently propagating changes made to any model to its counterpart. We evaluated the Shared Model experimentally. The evaluation shows that the framework can consistently synchronize Business and IT views related by correspondence patterns, after non-simultaneous independent editing.

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