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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.
21

Informační systém pro sledování polohy / Asset Tracking Information System

Labounek, Petr January 2011 (has links)
The work deals with recording and tracking of the objects in a certain area. It also puts mind to web services, mapping applications and modern standards, which seeks to compare and choose the best for this project. Then explore the existing systems and discusses their pros and cons, which specifies the requirements and propose solutions to information system built of selected technologies in order to create a friendly user interface. The proposed solution implements using modern PHP frameworks based on the MVP design pattern, and finally deals with verification of functionality and outline future developments.
22

Webový systém pro správu GPS dat v cloudovém prostředí / Web-Based GPS Data Management System in a Cloud Environment

Kasala, Viliam January 2015 (has links)
This thesis focuses on development of web-based GPS data management system in a cloud environment. The thesis introduces the most used application interfaces for building custom mapping applications. It offers a comparison of cloud platforms such as Google App Engine and OpenShift Online. It also deals with the design and the implementation of system for OpenShift Online platform. The system focuses on importing tracks from GPX format, managing tracks, viewing tracks on map tiles from Mapy.cz, searching for tracks, creating an elevation profile and various statistics.
23

Antioxidant Activity Of The Anti-Inflammatory Compound Ebselen And Its Analogues : Role Of Nonbonded Interactions

Sarma, Bani Kanta 07 1900 (has links)
Although considered as a poison for long time, the importance of selenium as an essential trace element is now well recognized. In proteins, the redox active selenium moiety is incorportated as selenocysteine (Sec), the 21st amino acid. In mammals, selenium exerts its redox activities through several selenocysteine-containing enzymes, which include glutathione peroxidase (GPx), iodothyronine deiodinase (ID) and thioredoxin reductase (TrxR). Although these enzymes have Sec in their active sites, they catalyze completely different reactions and their substrate specificity and cofactor or co-substrate systems are significantly different. The most widely studied selenoenzyme GPx protects various organisms from oxidative stresses by catalyzing the reduction of hydroperoxides by using glutathione (GSH) as cofactor. The chemical aspects of the reduction of hydroperoxide by GPx have been extensively studied with the help of synthetic selenium and tellurium compounds. For example, 2-phenyl, 1, 2-benzoisoselenazol-3(2H)-one, commonly known as ebselen exhibits significant GPx activity by using GSH as cofactor. The anti-inflammatory, antiatherosclerotic and cytoprotective properties of ebselen have led to the design and synthesis of nex GPx mimics for potential therapeutic applications. In the first chapter, the importance of selenium in biochemistry in general and the function of selenoenzyme GPx and its synthetic mimics in particular are discussed. In the second chapter, the importance of ebselen as a GPx mimic and how thiol exchange reaction in the selenenyl sulfide intermediate deactivates its catalytic cycle and the possible ways to overcome thiol exchange reaction are described. The third chapter deals with the first synthetic chemical model that effectively mimics the unusual cyclization of sulfenic acid to a sulfenyl amide in protein Tyrosien Phosphatase 1B(PTP1B). PTP1B is a cysteine containing enzyme where the sulfenic acid (PTP1B-SOH) intermediate produced in response to its oxidation by H2O2 is rapidly converted into a sulfenyl amide species, in which sulfur atom of the catalytic cysteine is covalently bonded to the main chain nitrogen of an adjacent serine residue. This unusual protein modification in PTP1B has been proposed to protect the sulfur centre from irreversible oxidation to sulfinic acid and and sulfonic acids. In the fourth chapter, it is shown that not only the catalytic efficiency of ebselen but also its phosphatase like behavior is important for its antioxidant activity. Ebselen is regenerated from selenenic acid (R-SeOH) under a verity of conditions, which protects its selenium centre from irreversible oxidation and thus reduces its toxicity. The fifth chapter deals with spirodizaselenurane and Spirodiazatellurane. Although the chemistry of spirodioxyselenuranes and spirodiazasulfuranes has been studied extensively due to their interesting structural and stereochemical properties, there is no example of stable spirodiazaselenurane and its tellurium analogues. In the fifth chapter, the synthesis, structure and GPx-like activity of the spirodizzaselenurane and spirodiazatellurane are discussed. In summary, the synthetic sulfenic acids and seleneric acids undergo cyclization to their corresponding sulfenyl amides and selenenyl amides and thus protect their sulfur and selenium centers from irreversible inactivation. We have also observed that selenoxides and telluroxides with nearby amide moieties undergo cyclization to their corresponding cyclic spiro compounds. This unusual transformation of sulfenic acids has been recently discovered in PTP1B. As the redox regulation cycle of PTP1B and the catalytic cycle of GPx are similar we believe that GPx may involve a selenenyl amide intermediate in its catalytic cycle.
24

Synthetic Antioxidants : Structure-Activity Correlation Studies Of Glutathione Peroxidase Mimics And Peroxynitrite Scavengers

Bhabak, Krishna Pada 07 1900 (has links)
Reactive oxygen species (ROS) such as superoxide radical anion (O2•¯), hydroxylradical (OH•), hydrogen peroxide (H2O2) and peroxynitrite (ONOO-) that are produced during the metabolism of oxygen under oxidative stress in aerobic organisms destroy several key biomolecules and lead to a number of disease states. Mammalian systems possess several effective defense mechanisms including antioxidant enzymes to detoxify these ROS. The selenocysteine-containing Glutathione peroxidase (GPx) is particularly an efficient enzyme in the detoxification of H2O2 and other hydroperoxides by using glutathione (GSH) as cofactor. The chemistry at the active siteof GPx has been extensively investigated with the help of synthetic selenium compounds. Although the anti-inflammatory compound ebselen(2-phenyl-1,2-benzoisoselenazol-3(2H)-one) is undergoing phase III clinical trial as antioxidant, the chemistry of ebselen is still not understood. The present study on a number of ebselen derivatives with various N-substitutions reveals that the substitution at the N atom is important for the antioxidant activity. This study also suggests that the nature for thiol cofactor has a dramatic effect on the GPx activity of ebselen derivatives. It has been shown that ebselen exhibits very poor catalytic activity in the presence of aromatic thiols mainly due to strong Se….O nonbonded interactions that lead to extensive thiol exchange reactions in the selenenyl sulfide intermediate. To prevent the se….O interactions, a series of tertiary amide-based diselenides have been synthesized along with their secondary amide counterparts. Detailed structure-activity correlation studies reveal that the GPx-like activity of the sec-amide-based compounds can be significantly enhanced by the substitution at the free-NH group of sec-amide functionality. The N,N-dialkylbenzylamine-based diselenides exhibit their catalytic activities via the generation of selenols which was confirmed by the reaction with anti-arthritic gold(I) compounds. Interestingly, the replacement of the hydrogen atom at the 6th position of the benzene ring of N,N-dialkylbenzylamine-based diselenides by a methoxy group prevents the thiol exchange reactions mainly be weakening the Se…N interactions and thus enhances the GPx activity. On the other hand, the catalytic activity of the tert-amine-based diselenides can also be increased by replacing the tert-amino groups with the corresponding sec-amine moieties. It has been observed that the basic amino group in the amine-based diselenides deprotonates the selenol and also the thiol cofactor, which is crucial for the higher catalytic activities of the amine-based compounds. Peroxynitrite (PN, ONOO), a strong nitrating agent, is known to inactivate a number of proteins, enzymes and other biomolecules by nitration of tyrosine residues. In this study, we have shown that the commonly used antithyroid drugs and their analogues inhibit protein tyrosine nitration. This study reveals that antithyroid agents having PN scavenging activity may be beneficial of hyperthyroidism as these compounds may protect the thyroid gland from nitrative or nitrosative stress.
25

Χρήση WSN για ιχνηλάτηση της τροχιάς ενός κινητού με εφαρμογή του walking GPS

Αρβανιτόπουλος, Αναστάσιος 04 October 2011 (has links)
Τα τελευταια χρόνια ειμαστε μαρτυρες ενός εντυπωσιακού παραδόξου στο χώρο της τεχνολογίας. Ενώ όλη η ανθρωπότητα αναζητά το κάτι παραπάνω σε υπολογιστική ισχύ, σε χώρο αποθήκευσης και σε ταχύτητα, μικρές αυτόνομες συσκευές έρχονται να κατακτήσουν όλο και περισσότερους τομείς της καθημερινότητάς μας. Μονάδες με την ικανότητα της επεξεργασίας και της αποθήκευσης δεδομένων, της αίσθησης του περιβάλλοντος αλλά και της επικοινωνίας μεταξύ τους, ενσωματώνονται σχεδόν σε όλους τους τομείς δραστηριοποίησης του ανθρώπου. Ο τρόπος αυτό-οργάνωσης αυτών των κόμβων - μονάδων στα πλαίσια μεγάλων ασύρματων δικτύων αισθητήρων, και η συλλογή δεδομένων από μια ευρεία περιοχή, τους δίνει τη δυνατότητα λήψης αποφάσεων, πολλές φορές κρίσιμων, ανάλογα με τις επικρατούμενες συνθήκες. Τα παραπάνω χαρακτηριστικά των δομικών στοιχείων των ασυρμάτων δικτύων αισθητήρων, σε συνδυασμό με τις υπηρεσίες της υψηλής και καθιερωμένης τεχνολογίας του συστήματος GPS (Global Positioning System) μπορούν να δημιουργήσουν έναν εκρηκτικό συνδυασμό και ερευνητικές ιδέες για ανάπτυξη αστικών εφαρμογών αυτοματισμού, στο πλαίσιο των λεγόμενων «έξυπνων πόλεων». Μέσα σε ένα απέραντο δίκτυο ασυρμάτων αισθητήρων, αποτελούμενο από χιλιάδες οντότητες, η ικανότητα του κάθε κόμβου να εντοπίζει την θέση του και να την μοιράζεται με τους υπόλοιπους, κερδίζει ολοένα και περισσότερο έδαφος ειδικά σε θέματα δρομολόγησης. Η χρήση της τεχνολογίας GPS από έναν κόμβο, αντικείμενο που μελετάμε στη παρούσα εργασία, μπορεί να οδηγήσει από την επιτυχή εφαρμογή του Geographical Routing σε ένα WSN, μέχρι την υλοποίηση απαιτητικών εφαρμογών για αντιγραφή κίνησης αλλά και δημιουργίας «έξυπνων αυτοκινητόδρομων» μέσα στους οποίους θα γίνεται αυτόματη πλοήγηση των κινητών υπό την επίβλεψη ενός μεγάλου WSN με κόμβους που συνεργάζονται με το σύστημα δορυφορικού εντοπισμού θέσης αλλά και μεταξύ τους. Όπως γίνεται άμεσα αντιληπτό, η παρούσα εργασία, που πραγματεύεται την σωστή συνεργασία και επικοινωνία ενός δικτύου ασυρμάτων αισθητήρων με την τεχνολογία GPS για την ιχνηλάτηση της πορείας ενός κινητού, μπορεί να δώσει μελλοντική τροφή για ενασχόληση σε πολλαπλά ερευνητικά επίπεδα. Η εργασία μας χωρίστηκε σε τρείς θεματικές ενότητες. Η πρώτη αφορά τον τομέα του WSN και του προγραμματισμού των κόμβων, για επικοινωνία με τους δορυφόρους, με τον υπολογιστή αλλά και μεταξύ τους, με τις απαραίτητες λειτουργικές εφαρμογές που κληθήκαμε να υλοποιήσουμε. Η δεύτερη αναφέρεται στην εργασία μας από την πλευρά του υπολογιστή, που λειτουργεί σαν συλλέκτης των δεδομένων του δικτύου, και τη σύνδεση του συστήματός μας με την πρότυπη εφαρμογή Google EarthTM για απεικόνιση σε πραγματικό χρόνο της τροχιάς που ακολουθεί ένα κινητό. Η τρίτη ενότητα περιλαμβάνει εκτέλεση πειραμάτων χρήσης του συστήματος που σχεδιάσαμε και παράθεση οπτικοποιημένων αποτελεσμάτων, για την εύκολη εξαγωγή χρήσιμων συμπερασμάτων όσον αφορά στη λειτουργικότητά του. / The last few years we witness a striking paradox in the field of technology. While all humanity is seeking for more computing power, more storage capabilities and more proccessing speed, small autonomous devices have appeared to occupy more and more areas of our lives in the daily routine. Units with the capabilities of data proccessing, data storage, enviromental sensing and communication with each other, are incorporated in almost all areas of human activity. The way in which these nodes are self-organized into large Wireless Sensor Networks and their ability to collect data from a wide area, enables them in taking decisions, critical ones sometimes, according to the prevailing conditions. The above characteristics of the components of wireless sensor networks, combined with the services of the established and standard technology of the GPS (Global Positioning System) can create ideas for research and development of urban applications of automation in the so-called “smart cities”. In a vast network of wireless sensors, consisting of thousands of entities, the ability of each node to detect its position and share it with others, is gaining more and more ground especially in routing topics. The use of GPS technology from a node, which is one of the subjects we study in this thesis, could lead from the successful implementation of the Geographical Routing, to the implementation of more demanding applications for motion replication but also to creating “smart highways” through which mobiles will execute an automatic navigation, supervised by a large WSN consisting of nodes cooperating with the satellite positioning system and with each other. As is readily apparent, the present thesis which is dealing with the good cooperation and communication of a wireless sensor network with the GPS technology in order to trace the path of a mobile, can provide room for future involvement in multiple levels of research. Our work was divided into three thematic sections. The first concerns the field of WSN and node programming so that they can be able to communicate with satellites, with the computer and with each other, by installing them with the necessary functional applications that we had to implement. The second section refers to our work on the computer side, which acts as a network data collector, and the link of our system with the standard Google EarthTM application to display the path of a mobile in real – time. The third section includes conducting experiments using the system we designed. The results are visualised and listed for an easy extraction of usefull conclusions regarding the functionality of our system.
26

Cyklistický/běžecký tréninkový deník využívající GPS data / Cycling/Running Training Diary Using GPS Data

Skalický, Martin January 2011 (has links)
This master's thesis practical goal is to create an application with usefull graphical users interface, which allows to import training data from GPS device. Also it will generate graphical and statistical outputs of achived results with export option to HTML and tabular processors format. Theoretical part of this thesis presents introduction to creating of a training diary, short description of GPS system function, as next it describes GPS data storage formats and application design.

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