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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.
151

A Systolic Array Based Reed-Solomon Decoder Realised Using Programmable Logic Devices

Biju, S., Narayana, T. V., Anguswamy, P., Singh, U. S. 11 1900 (has links)
International Telemetering Conference Proceedings / October 30-November 02, 1995 / Riviera Hotel, Las Vegas, Nevada / This paper describes the development of a Reed-Solomon (RS) Encoder-Decoder which implements the RS segment of the telemetry channel coding scheme recommended by the Consultative Committee on Space Data Systems (CCSDS)[1]. The Euclidean algorithm has been chosen for the decoder implementation, the hardware realization taking a systolic array approach. The fully pipelined decoder runs on a single clock and the operating speed is limited only by the Galois Field (GF) multiplier's delay. The circuit has been synthesised from VHDL descriptions and the hardware is being realised using programmable logic chips. This circuit was simulated for functional operation and found to perform correction of error patterns exactly as predicted by theory.
152

Correction d'une erreur induite expérimentalement : je ne l'ai pas vue... mais je l'ai corrigée quand même

Al Roujoula, Ahmad Adel January 2004 (has links)
Mémoire numérisé par la Direction des bibliothèques de l'Université de Montréal.
153

Multiplex Gene Synthesis and Error Correction from Microchips Oligonucleotides and High-throughput Gene Screening with Programmable Double Emulsion Microfluidics Droplets

Ma, Siying January 2015 (has links)
<p>Promising applications in the design of various biological systems hold critical implications as heralded in the rising field of synthetic biology. But, to achieve these goals, the ability to synthesize and screen in situ DNA constructs of any size or sequence rapidly, accurately and economically is crucial. Today, the process of DNA oligonucleotide synthesis has been automated but the overall development of gene and genome synthesis and error correction technology has far lagged behind that of gene and genome sequencing. What even lagged behind is the capability of screening a large population of information on a single cell, protein or gene level. Compartmentalization of single cells in water-in-oil emulsion droplets provides an opportunity to screen vast numbers of individual assays with quantitative readouts. However these single-emulsion droplets are incompatible with aqueous phase analysis and are not controllable through molecule transports. </p><p>This thesis presents the development of a multi-tool ensemble platform targeted at high-throughput gene synthesis, error correction and screening. An inkjet oligonucleotide synthesizer is constructed to synthesize oligonucleotides as sub-arrays onto patterned and functionalized thermoplastic microchips. The arrays are married to microfluidic wells that provide a chamber to for enzymatic amplification and assembly of the DNA from the microarrays into a larger construct. Harvested product is then amplified off-chip and error corrected using a mismatch endonuclease-based reaction. Bacterial cells baring individual synthetic gene variants are encapsulated as single cells into double-emulsion droplets where cell populations are enriched by up to 1000 times within several hours of proliferation. Permeation of Isopropyl-D-1-thiogalactopyranoside (IPTG) molecules from the external solution allows induction of target gene expression. The induced expression of the synthetic fluorescent proteins from at least ~100 bacteria per droplet generates clearly distinguishable fluorescent signals that enable droplets sorting through fluorescence-activated cell sorting (FACS) technique. The integration of oligo synthesis and gene assembly on the same microchip facilitates automation and miniaturization, which leads to cost reduction and increases in throughput. The capacity of double emulsion system (millions discrete compartments in 1ml solution) combined with high-throughput sorting by FACS provide the basis for screening complex gene libraries for different functionality and activity, significantly reducing the cost and turn-around time.</p> / Dissertation
154

Operating correction factor of PV system : Effects of temperature, angle of incidence and invertor in PV system performance

Lopez Ramirez, Izar January 2017 (has links)
In this project, the correction factor of different solar panels of the laboratory of the University of Gävle, located in Sweden, is going to evaluated. The solar modules’working conditions are different from the ones used to test them in the laboratory. In the laboratory. the output energy of the modules is less than in working conditions,and therefore a correction factor is going to be calculated from the data collected, inorder to describe the factors that affect the performance of the solar modules.Also, the obtained correction factor validity for different PV systems it is going to be examined, determining which system has a better correction factor and the energy losses due to temperature, angle of incidence and micro invertor.
155

Sentiment de vulnérabilité et risques liés au milieu de travail : étude de l'insécurité parmi les agents de correction fédéraux

Lavoie, Valérie January 2005 (has links)
Mémoire numérisé par la Direction des bibliothèques de l'Université de Montréal.
156

Chování trenéra - zkoumání didaktických problémů / The behaviour of coach - exploring didactic problems

Schwarz, Václav January 2013 (has links)
Title: The behaviour of coach - exploring didactic problems Objectives: The aim of my work is to create a scoping study and the use of feedback information in the training unit. Research questions: How should be feedback information mediated to the recipient? How often and in what forms to use feedback in the training unit? Methods: In my work I used the method of data acquisition, data analysis method and the method of narrative overview. I have summarized the information and made conclusions. Results: The goal of this work was completed. The research questions were answered. It was presented instructions for coaches. Keywords: correction, feedback information, instruction
157

Comparison of AdvanSyncTM and intermaxillary elastics in the correction of Class II malocclusions: A cephalometric study / Comparison of AdvanSyncTM and Intermaxillary Elastics in the Correction of Class II Malocclusions: A Cephalometric Study

Jayachandran, Santhosh 13 June 2016 (has links)
Objectives: To compare the skeletal, dentoalveolar and soft tissue effects of the AdvanSyncTM appliance with intermaxillary elastics in the correction of Class II malocclusions in growing patients. Materials and Methods: A retrospective study was conducted using lateral cephalograms of patients taken pre-treatment (T1) and post-comprehensive orthodontic treatment (T2). 41 patients consecutively treated with AdvanSyncTM were compared to 41 similar patients treated with intermaxillary Class II elastics. All patients had significant growth potential during treatment, as assessed by cervical vertebral maturation. A comparison group was generated from historical databases and matched to the experimental groups for skeletal age, gender and craniofacial morphology. Treatment changes were evaluated between the time points using a custom cephalometric analysis generating 31 variables as well as regional superimpositions. Data was analyzed using one-way analysis of variance and Tukey-Kramer tests. Results: The effects of AdvanSyncTM and fixed orthodontics (T2-T1) included maxillary growth restriction, protrusion, proclination and intrusion of mandibular incisors as well as mesialization of mandibular molars (p<0.01). The effects of Class II elastics and fixed orthodontics were similar to AdvanSyncTM, with the exceptions of less maxillary growth restriction and greater retrusion and retroclination of maxillary incisors (p<0.01). Significant mandibular growth stimulation, relative to untreated controls, did not occur with either modality. Conclusion: AdvanSyncTM and intermaxillary elastics were effective in normalizing Class II malocclusions during comprehensive fixed orthodontics. AdvanSyncTM produced its effects through maxillary skeletal growth restriction and mandibular dentoalveolar changes. Class II elastics worked primarily through dentoalveolar changes in both the maxilla and mandible. / October 2016
158

Evaluating the relationship between Modis and AVHRR vegetation indices

Malherbe, Johan 14 November 2006 (has links)
Student Number : 0216831W - MSc research report - School of Environmental Sciences - Faculty of Science / This report deals with the relationship between the NDVI obtained from the NOAA AVHRR sensor and that obtained from the MODIS sensor. The relationship is quantitatively assessed for distinct polygons over various land-cover types in the northeastern Kwa-Zulu Natal Province of South Africa. Spatial and temporal variations in the relationships are addressed and discussed with reference to spectral response, sunsensor- target geometries and atmospheric factors. Specifically, various methods are investigated to estimate a MODIS-equivalent NDVI from the AVHRR NDVI and in so doing create the potential to develop a self-consistent NDVI between the historically available AVHRR NDVI dataset and the relatively new MODIS NDVI dataset. NOAA-16 AVHRR NDVI data and AQUA MODIS NDVI data for the two-year period from January 2002 to December 2003 are used to develop the method. A linear relationship exists between the AVHRR and MODIS NDVI. However, spatial variations in the relationship in terms of land-cover and mean NDVI are pointed out. The potential of atmospheric corrections applied to AVHRR data through a radiative transfer atmospheric correction model to improve the relationship between the two NDVI datasets is also investigated. The importance of geo-location accuracy of the AVHRR NDVI dataset is assessed in the light of the accuracy obtainable with the proposed method to estimate a MODIS-equivalent NDVI from the AVHRR NDVI. A method to estimate the MODIS NDVI from the AVHRR NDVI that takes the mean AVHRR NDVI value into account, as opposed to a constant linear relationship over all the points, is proposed. Atmospheric correction is shown not to improve the accuracy of the method in a statistically significant way. The root-mean-square error of the proposed method is in the order of 0.05 NDVI units and varies between 0.5 and 2 standard deviations of the MODIS NDVI over an entire season.
159

Room Correction for Smart Speakers

Mårtensson, Simon January 2019 (has links)
Portable smart speakers with wireless connections have in recent years become more popular. These speakers are often moved to new locations and placed in different positions in different rooms, which affects the sound a listener is hearing from the speaker. These speakers usually have microphones on them, typically used for voice recording. This thesis aims to provide a way to compensate for the speaker position’s effect on the sound (so called room correction) using the microphones on the speaker and the speaker itself. Firstly, the room frequency response is estimated for several different speaker positions in a room. The room frequency response is the frequency response between the speaker and the listener. From these estimates, the relationship between the speaker’s position and the room frequency response is modeled. Secondly,an algorithm that estimates the speaker’s position is developed. The algorithm estimates the position by detecting reflections from nearby walls using the microphones on the speaker. The acquired position estimates are used as input for the room frequency response model, which makes it possible to automatically apply room correction when placing the speaker in new positions. The room correction is shown to correct the room frequency response so that the bass has the same power as the mid- and high frequency sounds from the speaker, which is according to the research aim. Also, the room correction is shown to make the room frequency response vary less with respect to the speaker’s position.
160

High-Performance Decoder Architectures For Low-Density Parity-Check Codes

Zhang, Kai 09 January 2012 (has links)
The Low-Density Parity-Check (LDPC) codes, which were invented by Gallager back in 1960s, have attracted considerable attentions recently. Compared with other error correction codes, LDPC codes are well suited for wireless, optical, and magnetic recording systems due to their near- Shannon-limit error-correcting capacity, high intrinsic parallelism and high-throughput potentials. With these remarkable characteristics, LDPC codes have been adopted in several recent communication standards such as 802.11n (Wi-Fi), 802.16e (WiMax), 802.15.3c (WPAN), DVB-S2 and CMMB. This dissertation is devoted to exploring efficient VLSI architectures for high-performance LDPC decoders and LDPC-like detectors in sparse inter-symbol interference (ISI) channels. The performance of an LDPC decoder is mainly evaluated by area efficiency, error-correcting capability, throughput and rate flexibility. With this work we investigate tradeoffs between the four performance aspects and develop several decoder architectures to improve one or several performance aspects while maintaining acceptable values for other aspects. Firstly, we present a high-throughput decoder design for the Quasi-Cyclic (QC) LDPC codes. Two new techniques are proposed for the first time, including parallel layered decoding architecture (PLDA) and critical path splitting. Parallel layered decoding architecture enables parallel processing for all layers by establishing dedicated message passing paths among them. The decoder avoids crossbar-based large interconnect network. Critical path splitting technique is based on articulate adjustment of the starting point of each layer to maximize the time intervals between adjacent layers, such that the critical path delay can be split into pipeline stages. Furthermore, min-sum and loosely coupled algorithms are employed for area efficiency. As a case study, a rate-1/2 2304-bit irregular LDPC decoder is implemented using ASIC design in 90 nm CMOS process. The decoder can achieve an input throughput of 1.1 Gbps, that is, 3 or 4 times improvement over state-of-art LDPC decoders, while maintaining a comparable chip size of 2.9 mm^2. Secondly, we present a high-throughput decoder architecture for rate-compatible (RC) LDPC codes which supports arbitrary code rates between the rate of mother code and 1. While the original PLDA is lack of rate flexibility, the problem is solved gracefully by incorporating the puncturing scheme. Simulation results show that our selected puncturing scheme only introduces the BER performance degradation of less than 0.2dB, compared with the dedicated codes for different rates specified in the IEEE 802.16e (WiMax) standard. Subsequently, PLDA is employed for high throughput decoder design. As a case study, a RC- LDPC decoder based on the rate-1/2 WiMax LDPC code is implemented in CMOS 90 nm process. The decoder can achieve an input throughput of 975 Mbps and supports any rate between 1/2 and 1. Thirdly, we develop a low-complexity VLSI architecture and implementation for LDPC decoder used in China Multimedia Mobile Broadcasting (CMMB) systems. An area-efficient layered decoding architecture based on min-sum algorithm is incorporated in the design. A novel split-memory architecture is developed to efficiently handle the weight-2 submatrices that are rarely seen in conventional LDPC decoders. In addition, the check-node processing unit is highly optimized to minimize complexity and computing latency while facilitating a reconfigurable decoding core. Finally, we propose an LDPC-decoder-like channel detector for sparse ISI channels using belief propagation (BP). The BP-based detection computationally depends on the number of nonzero interferers only and are thus more suited for sparse ISI channels which are characterized by long delay but a small fraction of nonzero interferers. Layered decoding algorithm, which is popular in LDPC decoding, is also adopted in this paper. Simulation results show that the layered decoding doubles the convergence speed of the iterative belief propagation process. Exploring the special structure of the connections between the check nodes and the variable nodes on the factor graph, we propose an effective detector architecture for generic sparse ISI channels to facilitate the practical application of the proposed detection algorithm. The proposed architecture is also reconfigurable in order to switch flexible connections on the factor graph in the time-varying ISI channels.

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