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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.
121

Metoda za povezivanje mernog sistema i računarapomoću konverzije podataka iz I2S u TCP/IP protokol / Method for Connecting Measuring System With Computer by Converting Data From I2S to TCP/IP Protocol

Sakal Tibor 01 June 2017 (has links)
<p>Ova doktorska disertacija predstavlja istraživački rad sproveden sa ciljem da re&scaron;i problem koji se odnosi na realizaciju povezivanja laboratorijskog, medicinskog mernog uređaja sa personalnim računarom. Rezultat istraživačkog rada je op&scaron;ta metoda koja obezbeđuje efikasnu konverziju podataka I2S protokola u TCP/IP protokol.</p> / <p>This doctoral thesis presents the research work carried out in order to solve a practical problem, the realization of a connection between a medical measuring device and a personal computer. The result of the research is a general method that provides efficient data conversion from the I2S protocol to the TCP/IP protocol.</p>
122

Katabolická dráha hemu u chronické hepatitidy C / The Heme Catabolic Pathway in Chronic Hepatitis C

Subhanová, Iva January 2013 (has links)
This thesis focuses on the importance of the heme catabolic pathway in chronic hepatitis C (HCV). The aim is mainly to investigate, whether expresion/activity of key enzymes of the heme catabolic pathway, heme oxygenase (HMOX) and biliverdin reductase (BLVRA) in the liver and blood (study A) or promoter variations of HMOX1 and UDP- glucuronosyltransferase (UGT1A1) (study B) may be associated with the progression of fibrosis and may also predict antiviral treatment outcome in patients chronically infected with HCV. We set up a new sensitive method to quantify HMOX activity by reduction gas chromatography. We developed and extensively validated RealTime PCR assay for HMOX and BLVRA expression in the liver and peripheral blood leucocytes (PBL). The (GT)n and (TA)n dinucleotide variations in HMOX1 and UGT1A1 gene promoters, respectively, were determined by fragment analysis. No association was detected between either expression of HMOX/BLVRA or the HMOX1/ UGT1A1 promoter variants and the individual histological stages of liver disease in the HCV positive patients. A marked difference in BLVRA expression in PBL between the sustained responders (SVR) and patients with treatment failure (NVR) was detected before antiviral treatment and during the follow-up. Our data suggests, that BLVRA basal expression...
123

IMPLEMENTAÇÃO DE ARQUITETURAS DE PILHA UDP/IP EM HARDWARE RECONFIGURÁVEL BASEADO NO DESEMPENHO DE VAZÃO, LATÊNCIA E TAXA DE PERDA DE QUADROS / IMPLEMENTATION OF UDP/IP STACK ARCHITECTURES IN RECONFIGURABLE HARDWARE BASED ON THROUGHPUT, LATENCY AND FRAME LOSS RATE PERFORMANCE

Herrmann, Fernando Luís 11 March 2010 (has links)
Conselho Nacional de Desenvolvimento Científico e Tecnológico / This work presents the implementation of three architectures of UDP/IP network stack in reconfigurable hardware. Also, presents the development of a Tester based on the RFC 2544 methodology and implemented it in FPGA. This Tester was used to obtain the throughput, latency and frame loss rate results. The performance of the project shows, in average, throughput results 89% better in comparison with a network stack implemented in software (PC) and running over a general purpose microprocessor, for frames with 64 bytes. Regarding latency, the project is 389 times lower for frames with 64 bytes and 13 times lower for frames with 1518 bytes, than the PC. On behalf of frame loss rate, the project doesn t loss frames for any frame sizes used during the tests, while the PC has presented a frame loss of almost 98% for frames with 64 bytes. / Este trabalho apresenta a implementação de três arquiteturas da pilha de comunicação UDP/IP em hardware reconfigurável. Também apresenta o desenvolvimento de um Testador baseado na metodologia da RFC 2544 e implementado em uma placa dotada de dispositivo FPGA. Esse Testador foi utilizado na obtenção dos resultados de vazão, latência e taxa de perda de quadros. O desempenho do projeto apresentou, em média, 89% a mais de vazão, para quadros de 64 bytes, que uma pilha de comunicação implementada em software (PC) e executada sobre um microprocessador de propósito geral. Em termos de latência, o projeto apresentou uma latência 389 vezes menor para quadros de 64 bytes e 13 vezes menor para quadros de 1518 bytes, que o PC. E em relação à taxa de perda de quadros, o projeto não apresentou perda para nenhum dos tamanhos de quadros utilizados durante os testes, enquanto o PC apresentou perda de quase 98% para quadros de 64 bytes.
124

Modulární RGB LED displej s rozhraním Ethernet / Modular RGB LED display with Ethernet

Zemánek, Petr January 2014 (has links)
This thesis deals with an electronic circuit and a PCB of a modular RGB LED display with the Ehernet interface. Firstly, author describes a RGB colour model, features of RGB LED displays, ways of control them. The next chapter contains a short description of the Ethernet interface, UDP and TCP protocols and a lwIP TCP/IP stack. The last theoretical chapter is an introduction to ARM Cortex-M3 and Cortex-M4 based microcontrollers. The next chaper is deals with a hardware design of the modular RGB LED display. The device is designed to be modular. Individual devices can be combosed together and create a larger display. Data from the Ethernet interface will be displayed on the RGB LED matrix, resolution of the matrix is 32 × 32 (1024 diodes). A refresh frequency is 100 Hz, a color depth is High color (16 bits) and a scanning 1/16 (two rows is driven at the same time). The next chapter describes the firmware for the RGB LED display, all its logical parts including a web page. Author also created the PC application, which sends pictures using UDP protocol to individual modules.
125

Enhancing user satisfaction in 5G networks using Network Coding

Johansson, Victor January 2015 (has links)
Network data rates are growing rapidly. The data rates provided to the customers by their network providers vary from Mbps to Gbps. However, rarely do users get the promised peak throughput. In cellular networks, network conditions change based on obstacles, weather conditions between the client and the base stations, and even the movement of objects and people. As a result of the changes in the radio link, the data transfer rate can change rapidly, hence devices needs to adjust their communications based on the currently available data rate. The Transmission Control Protocol (TCP) is widely used for reliable data transfer over networks. However, TCP was initially designed when link data rates were much lower than the link data rates commonly available today. As a result, TCP does not perform well at high data rates, despite some of the changes that have been made to the protocol to support high data rate links. Moreover, TCP has problems adapting to large changes in link bandwidth (not caused by congestion), resulting in a lower average throughput than the link could potentially deliver. This thesis evaluates two different versions of the TCP protocol (e.g., TCP Reno and Cubic TCP) and proposes a network coding scheme to enhance users’ experience when communicating over unstable radio links. The performance of the two TCP protocols and Random Linear Network Coding (RLNC) scheme were measured in an emulated network environment. The results of these measurements were analyzed and evaluated. The analysis shows that RLNC can provide a higher throughput than TCP over a network with high packet loss. However, RLNC is a UDP based solution and does not implement congestion control algorithms or reliability. A new solution is proposed that increases reliability and implements network adaptation in RLNC solutions. The results obtained in this thesis can be used to develop a new protocol to increases the quality of users’ experience in high loss networks. / Datahastigheter över nätverk ökar drastiskt. Datahastigheterna som ges tillgängliga till användare av deras respektive dataleverantör kan variera från Mbit/s till Gbit/s. Det är dock inte ofta användare får ut vad som har lovats. I mobila nätverk kan nätverkets tillstånd ändras baserat på hinder, väderleksförhållanden mellan en klient och basstationerna, till och med beroende på förflyttning av objekt eller människor. På grund av detta så behöver användares utrustning anpassa dess kommunikation, baserat på den för närvarande tillgängliga datahastigheten. Transmission Control Protocol (TCP) används i stor utsträckning vid behovet av tillförlitlig dataöverföring över nätverk. Däremot så designades TCP när länkdatahastigheterna var mycket lägre än vad som är vanligen tillgängligt idag. På grund av detta så presterar inte TCP över höga datahastigheter, trots ändringar som har gjorts i protokollet för att stödja höghastighets datalänkar. Utöver det så har TCP svårt att anpassa sig efter stora ändringar i länkens bandbredd (som inte är orsakat av stockning), som resulterar i en mindre genomsnitts-dataström än vad länken potentiellt hade kunnat ge. Detta examensarbete utvärderar två olika versioner av TCP (e.g., TCP Reno och Cubic TCP) och föreslår ett sätt att använda network coding för att öka användares upplevelse vid dataöverföring över instabila radio länkar. Prestationerna av de två TCP versionerna och Random Linear Network Coding (RLNC) metoden har blivit mätt i en emulerad nätverksmiljö. Resultaten från dessa mätningar blev analyserade och utvärderade. Analysen visar att RLNC kan ge en högre dataström än TCP över ett nätverk med hög risk för paketförluster. Däremot så är RLNC en User Datagram Protocol (UDP) baserad lösning, och därav inte implementerar trängselkontrolls-algoritmer eller tillförlitlighet. Ett förslag till en ny lösning som ökar tillförlitlighet och implementerar nätverksanpassning till RLNC lösningar har presenterats. Resultaten från detta examensarbete kan användas till att utveckla nya protokoll för att öka kvalitén av användares upplevelse i nätverk med risk för hög paketförlust.
126

OPERATOR INTERFACES FOR CONTROLLING THE SERIAL STREAMING TELEMETRY CHANNEL VIA A COMMAND AND CONTROL LINK

Laird, Daniel T. 10 1900 (has links)
ITC/USA 2007 Conference Proceedings / The Forty-Third Annual International Telemetering Conference and Technical Exhibition / October 22-25, 2007 / Riviera Hotel & Convention Center, Las Vegas, Nevada / The Central Test and Evaluation Incentive Program, (CTEIP) is developing Integrated Network Enhanced Telemetry (iNET) to extend serial streaming telemetry (SST) with a command and control link. Command link interfaces link remote Advanced Range Telemetry (ARTM) transmitters (Tx) and receivers (Rx), developed under the ARTM CTEIP project, via graphical user interfaces (GUI). The communication channel links the iNET Tx on a vehicle network (vNET) and the iNET Rx on a ground station network (gNET) via a single GUI. The command link is an essential part of the pending iNET Technology Demonstration.
127

Isolation and evaluation of the sugarcane UDP-glucose dehydrogenase gene and promoter

Van der Merwe, Jennie 12 1900 (has links)
Thesis (PhD (Genetics. Plant Biotechnology))--University of Stellenbosch, 2006. / The young internodes of sugarcane are ideal targets for altering metabolism, through genetic manipulation, to potentially control known fungal diseases such as Smut or to increase sucrose yields in these regions that are currently being discarded. At present, no regulatory sequences that specifically drive transgene expression in young developing sugarcane tissues are available. The objective of this study was therefore to isolate and evaluate such a sequence. The promoter targeted for isolation in this study regulates the expression of UDP-glucose dehydrogenase (EC 1.1.1.22), an enzyme which catalyses the oxidation of UDP-glucose to UDP-glucuronic acid, a precursor for structural polysaccharides which are incorporated into the developing cell wall. A strong correlation between the expression of UDP-glucose dehydrogenase and a demand for structural polysaccharides in developing tissues could therefore be expected. The first part of this study addressed the general practicality of promoter isolation from sugarcane, a complex polyploid. A gene encoding UDP-glucose dehydrogenase was isolated from a sugarcane genomic library. The gene contains an open reading frame (ORF) of 1443 bp, encoding 480 amino acids and one large intron (973 bp), located in the 5’-UTR. The derived amino acid sequence showed 88 – 98% identity with UDP-glucose dehydrogenase from other plant species, and contained highly conserved amino acid motifs required for cofactor binding and catalytic activity. Southern blot analysis indicates a low copy number for UDP-glucose dehydrogenase in sugarcane. The possible expression of multiple gene copies or alleles of this gene was investigated through comparison of sequences amplified from cDNA prepared from different tissues. Although five Single Nucleotide Polymorphisms (SNP) and one small-scale insertion/deletion (INDEL) were identified in the aligned sequences, hundred percent identity of the derived amino acid sequences suggested the expression of different alleles of the same gene rather than expression of multiple copies. The finding that multiple alleles are expressed to provide the required level of a specific enzyme, rather than the increased expression of one dominant allele, is encouraging for sugarcane gene and promoter isolation. In the second part of the study the suitability of UDP-glucose dehydrogenase as a target for the isolation of a developmentally regulated promoter was investigated. The contribution of UDP glucose dehydrogenase to pentan synthesis, as well as the expression pattern and subcellular localisation of the enzyme in mature sugarcane plants was studied at the tissue and cellular level. Radiolabelling with positionally labelled glucose was used to investigate the relative contributions of glycolysis, the oxidative pentose phosphate pathway and pentan synthesis to glucose catabolism. Significantly (P=0.05) more radiolabel was released as CO2 from [6-14C]- glucose than [1-14C]-glucose in younger internodes 3, 4 and 5, demonstrating a significant contribution of UDP-glucose dehydrogenase to glucose oxidation in the younger internodes. In addition, there was significantly (P=0.05) more radiolabel in the cell wall (fiber) component when the tissue was labelled with [1-14C]-glucose rather than [6-14C]-glucose. This also demonstrates a selective decarboxylation of glucose in position 6 prior to incorporation into the cell wall and is consistent with a major role for UDP-glucose dehydrogenase in cell wall synthesis in the younger internodes. Expression analysis showed high levels of expression of both the UDP-glucose dehydrogenase transcript and protein in the leafroll, roots and young internodes. In situ hybridisation showed that the UDP-glucose dehydrogenase transcript is present in virtually all cell types in the sugarcane internode, while immunolocalisation showed that the abundance of the protein declined in all cell types as maturity increased. Results obtained confirmed that this enzyme plays an important role in the provision of hemicellulose precursors in most developing tissues of the sugarcane plant, indicating that UDP-glucose dehydrogenase was indeed a suitable target for promoter isolation. Lastly, the promoter region and first intron, located in the 5’-untranslated region (UTR) of this gene, were isolated and subsequently fused to the GUS reporter gene for transient expression analysis and plant transformation. Transient expression analysis showed that the presence of the intron was essential for strong GUS expression. Analysis of stably transformed transgenic sugarcane plants, evaluated in a green house trial, showed that the isolated promoter is able to drive GUS expression in a tissue specific manner under these conditions.
128

Deployable combat simulations via wireless architectures

Lock, Jeffrey S., Sr. 03 1900 (has links)
Approved for public release, distribution is unlimited / This thesis details the critical need for deployable combat simulations for training in today's surge force environment. To truly realize deployment of these simulations on Naval vessels and in remote theaters, simulations for training must be wireless. Wireless standards 802.11/a/b/g are presented in detail to highlight the strengths and weaknesses of each. This thesis then investigates the viability of deploying combat simulations for training using wireless devices. To this end, the Joint Semi-Automated Forces (JSAF), combat simulation model and the Virtual Helicopter (VEHELO) training simulation entity are tested in an 802.11a wireless environment against the VEHELO application in a wired environment. 802.11a is proposed as part of an overall solution to deploy combat simulations for training. This is primarily because of its high data rates and ability to co-locate access points without interference. Testing reveals that operating JSAF and Virtual Helicopter via the High Level Architecture (HLA) with User Datagram Protocol (UDP) packets in an 802.11a environment provides ample bandwidth with which to deploy combat simulation for training for the simulations conducted. / Lieutenant, United States Navy
129

Conception et synthèse d'imino-C-galactofuranosides comme inhibiteurs de la biosynthèse des galactanes mycobactériens

Liautard, Virginie 24 November 2008 (has links) (PDF)
Dans le contexte de la recherche de molécules actives agissant spécifiquement sur des microorganismes pathogènes tels que les mycobactéries, la biosynthèse du galactofuranose (Galf) constitue une cible chimiothérapeutique intéressante. Notre approche consiste à concevoir et synthétiser des iminosucres originaux comme inhibiteurs potentiels et/ou sondes mécanistiques des enzymes mises en jeu : l'UDP-Galp mutase (UGM) et les Galf transférases (GlfT). Pour cela nous avons développé deux approches stéréodivergentes conduisant à des imino-C-galactosides originaux.<br>Nous avons mis au point une méthodologie performante basée sur l'addition de nucléophiles silylés, assistée par acide de Lewis, sur une N-glucosylamine protégée qui a permis la synthèse d'une petite librairie de dérivés alpha-1,4-didésoxy-1,4-imino-D-galactitols substitués en position C-1. L'utilisation de séquences synthétiques convergentes, notamment une métathèse croisée, nous a ensuite conduits à des analogues de l'UDP-Galf possédant un squelette iminosucre diversement lié à l'UridineMonoPhosphate.<br>D'autre part, la cycloaddition 1,3-dipolaire entre un phosphonate fonctionnalisé et une nitrone cyclique de configuration D-galacto a conduit régio- et stéréosélectivement à l'isoxazolidine, analogue de l'UDP-Galf et précurseur d'UMP-beta-1,4-iminogalactitol. Cette approche concise et efficace permet également l'obtention d'analogues disaccharidiques du Galf. En effet, nous avons constaté qu'une nitrone polyhydroxylée non protégée réagit facilement, dans l'eau, avec des oléfines de sucre pour conduire au cycloadduit correspondant, précurseur d'imino-disaccharide.<br>L'évaluation biologique de ces composés comme inhibiteurs de l'UGM et de GlfT2 a montré qu'un analogue de l'UDP-Galf présente une activité intéressante de GlfT2.
130

Implementering av realtidsvideolänk med MPEG- och wavelet-teknik / Implementation of aReal Time Video Transmission Link using MPEG- and Wavelet Methods

Heijdenberg, Karl, Johansson, Thomas January 2004 (has links)
<p>At Saab Aerosystems, situated in Linköping Sweden, there is a presentation and manoeuvre simulator simulating the fighter jet JAS-39 Gripen. This flight simulator is called PMSIM. In this thesis we study how to transfer sensor images generated by PMSIM to other simulators or desktop computers. The transmission is band-limited so some kind of image coding must be used. Because of this the greater part of this thesis is concerned with image coding. </p><p>To fulfill the real time requirement the image coding has to be quite simple and the transmission has to be fast. To achieve fast transmission the network protocol has to use as little overhead information as possible. Such a protocol has therefore been designed and implemented. </p><p>This report also includes a survey about real radio links. This survey investigates how the quality of the video stream can be affected by noise and other disturbing elements. </p><p>The work in this report revolves around the implementation of a video link. The purpose of this link is to transmit and display sensor images. The link consists mainly of the three following parts: image coder, network link and image player. The image coding has been focused on MPEG and wavelets. </p><p>The wavelet technique is not a well known coding principle for video applications. Although as a coding technique for still images the technique is well known. For instance it is used in the JPEG2000-standard. Experiments conducted and published in this report suggest that for some applications the wavelet technique can be a viable candidate, with respect to the MPEG technique, for a video coder.</p>

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