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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.
411

Principy zabezpečení bezdrátových standardů / Principles of the Wireless Standards Security

Vokál, Martin January 2007 (has links)
Computer networks are in the scope of the IEEE organization normalized by the 802 board which currently comprises six working groups for wireless communications. IEEE 802.11 for wireless local area networks, IEEE  802.15 for wireless personal area networks, IEEE 802.16 for wireless metropolitan area networks, IEEE 802.20 for mobile broadband wireless access, IEEE 802.21 for media independent handover and IEEE 802.22 for wireless regional area networks. This master's thesis focuses on a security analysis of particular standards, describes threats, vulnerabilities, current security measures and mutually compares wireless specifications from a security point of view. The conclusion is devoted to overall evaluation of the project, to its contributions, possible enhancements and continuation in the form of consequential studies.
412

Biotopmanagement in Festungsanlagen – Trittsteine und Habitate für die Biotopvernetzung

Junghans, Veikko 08 April 2021 (has links)
Durch vegetationsökologische Feldstudien wurde das Biotop- und Arteninventar verschiedener Festungsanlagen des 19. Jahrhunderts in Deutschland, Polen und Litauen untersucht. Ein Ziel der Untersuchung war die Bewertung der Standorte für eine Einbindung in den FFH Biotop-Verbund, ergänzt durch Auswertungen historischer Luftbilder sowie Sentinel2-Fernerkundungsdaten. Die Festungsanlagen neigten in den letzten Jahrzehnten zu einer Wiederbewaldung durch ausbleibende Nutzung und Pflege der Offenlandbereiche. Innerhalb weniger Jahrzehnte sind vor Ort vor allem stadtwaldähnliche Standorte entstanden. Eine Entwicklung hin zu standorttypischen Ausprägung einer HPNV oder anderer Gesellschaften, die als Biotoptypen nach Anhang I FFH-RL ausweisbar wären, ist an den untersuchten Standorten nicht beobachtet worden. Hohe Biotopqualitäten in Offenland-Standorten sowie anderen Biotoptypen sind nicht beobachtet worden. Festungen und deren Biotope sind als Novel Ecosystems ausweisbar und wären nur als solche in das Biotopverbundsystem integrierbar. Satellitenbasierte Auswertungen bilden die Kleinräumigkeit der örtlichen Biotopstrukturen –und deren Vielfalt nur bedingt ab. Fehlende Pflege und Nutzung von Festungen sowie aufkommende Waldbestände verursachen eine sukzessive Degradation und Schädigung der Bausubstanz. Eine naturschutzfachliche Begründung für das grundsätzliche Ausbleiben von Sanierung und Bausubstanzerhalt existiert nicht, auch wenn diese Standorte oftmals Habitate für Arten des Anhang IV der FFH-RL aufweisen. Im Gegensatz, die Pflege und der Erhalt des Kulturerbes „Festungsanlagen“ wird von der europäischen Naturschutz- und vor allem Kulturagenda sogar gefordert, da diese neben noch unspezifiziertem Natur- und Erholungswert auch einen intrinsischen gesamteuropäischen Kulturwert haben. Das muss bei der lokalen Raum- und Naturschutzfachplanung sowie in der regionalen Landespflege berücksichtigt werden. / The biotope and species inventory of various fortifications of the 19th century in Germany, Poland and Lithuania was examined through vegetation-ecological field studies. One aim of the study was to evaluate the locations for integration into the FFH biotope network, supplemented by evaluations of historical aerial photos and Sentinel2 remote sensing data. Investigated fortifications tended to reforest in recent decades due to the lack of use and maintenance of the open land areas. Within a few decades, urban forest-like sites have developed here at the investigated sites. A development towards site-typical expressions of PNV or other communities, which could be designated as FFH biotopes according to Annex I of the Habitats Directive, has not been observed. High biotope qualities in open land biotopes and other types were not observed Fortresses and their biotopes can be designated as Novel Ecosystems and should only be integrated as such into the biotope network. Satellite based evaluations only provide a limited picture of the small-scale nature and diversity of local biotope structures. The lack of maintenance and use of fortresses as well as emerging forest stands cause successive degradation and damage to the building fabric. There is no nature conservation justification for the fundamental lack of remediation and preservation of building fabric, even though these sites often have habitats for species listed in Annex IV of the Habitats Directive. In contrast, the care and preservation of the cultural heritage "fortifications" is even demanded by the European nature conservation and cultural agenda, as they have an intrinsic pan-European cultural value in addition to still unspecified nature and recreational value. This is even reflected by the aim of the Habitats Directive. This must be taken into account in local spatial and nature conservation planning and in regional land management.
413

Riding Red Ink: Public Ownership of Mass Transit in Indianapolis

Wilhite, Ryan Daniel January 2011 (has links)
**Note** During the research process, IndyGo donated some of the resources cited within this paper to the Indiana Historical Society. That collection has not been archived yet. Further, IndyGo may have placed other documents (created during the time of public ownership) in the Indiana State Archives or the Indiana State Library. / Indiana University-Purdue University Indianapolis (IUPUI) / Today, most urban mass transit providers are publicly owned. Just a few decades ago, and for a majority of the history of mass transit, private owners provided transportation for communities. The decline of private ownership in Indianapolis resulted in transit crisis that pitted private owners against local government, riders and community groups. Advocates lambasted the private owners for their profit-first tactics, pointing to the dividends gained by the private owners. These owners, the Midland Transportation Corporation, also owned the mass transit companies in Milwaukee, Wisconsin and Louisville, Kentucky. Indianapolis politicians, residents and newspapers, all firmly conservative, hoped private owners could continue to operate Indianapolis Transit Systems without public assistance. The imminent failure prompted a discussion of the future of transportation in the city of Indianapolis. Community groups hoped the new public corporation would increase service for Indianapolis and not continue the skeleton system managed by the private owners. A storm of uncontrollable events prevented the robust expansion of the new public corporation and its lack of funding resulted in a continuing decline of service, much akin to the private owners that were abhorred by transit riders. Public ownership in Indianapolis revealed the importance of public ownership in the historiography of mass transportation and urban history. The regional investigation of Midland Transportation confirmed the notion of transit as a unique industry, both in its industrial relations and influence of the locality. The basic rationale for public ownership in Indianapolis would be the most important: the provision of public transportation for those unable to afford private transportation to obtain necessary services.
414

Model metropolitní optické sítě / Model of the metropolitan optical network

Prudík, Jiří January 2008 (has links)
The purpose of this master’s thesis is foremost to provide a simple guide how to build elements of optical metropolitan area network. The basic model consists to sequence of construction, network topology, passive and active parts. The collection contains examples of alternative technology such as Wireless LAN with different frequency. The optical network construction based on optical cable, fibres, splices, trays, adapters, connectors and active parts for example a lot of media convertor models. After that there are demonstrating type of wavelength division multiplexer used in metropolitan area network – passive planar PCL splitter. One of the passive planar splitter are used to increase optical fibre channel. At the end of the collection a simplified examples of used measurements – optical time domain reflectometry and optical fibre transmission. Contains standard protocols or reflectogram. The conclusion of this thesis summarizes costs of FTTb (Fibre To The Building) model of optical metropolitan area network in Czech republic and future contribution for society.

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