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151	API de Segurança e Armazenamento de uma Arquitetura Multibiométrica para Controle de Acesso com Autenticação Contínua. / Security and Persistence APIs of a Multi-biometric Access Control Architecture for Continuous Authentication. Oliveira, Adriana Esmeraldo de 16 September 2011 (has links) Made available in DSpace on 2015-05-14T12:36:30Z (GMT). No. of bitstreams: 1 arquivototal.pdf: 4594295 bytes, checksum: bd4f4df655903b796eb6cf79a5060ded (MD5) Previous issue date: 2011-09-16 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / A biometric system that employs one single biometric characteristic is constrained. This limitation can be reduced by fusing the information presented by multiple sources. A system that consolidates the evidence presented by multiple biometric sources is known as a multibiometric system. In such a context, this work proposes the security and persistence APIs of a multi-biometric architecture, which is capable of using one or more biometric modalities. In access control applications, a user might be forced to authenticate in order to give an unauthorized access to a criminal. As an alternative to this problem, the API uses a continuous authentication process, which verifies if the user identified at the start of the software application is still able to remain on the system, without human interferences or breaks in the process. Much of the literature on biometric system design has focused on system error rates and scaling equations. However, it is also important to have a solid foundation for future progress as the processes and systems architecture for the new biometric application are designed. Hence, the designed architecture made it possible to create a well-defined API for multibiometric systems, which may help developers to standardize, among other things, their data structure, in order to enable and facilitate templates fusion and interoperability. Therefore, the developed security and persistence APIs support a multi-biometric access control architecture. This architecture is extensible, that is, capable of easily comprising new biometric characteristics and processes, yet making it possible to use a template security mechanism. The APIs were designed and implemented. They were demonstrated by a prototype application, through which it was possible to conduct the test experiments. / Um sistema biométrico que empregue uma única peculiaridade ou traço característico é restrito. Esta limitação pode ser suavizada pela fusão dos dados apresentados por múltiplas fontes. Um sistema que consolida a evidência apresentada por múltiplas fontes biométricas é conhecido como um sistema multibiométrico. Nesse contexto, este trabalho propõe a interface de aplicação (API) de segurança e armazenamento de uma arquitetura multibiométrica, com habilidade de empregar uma ou mais modalidades biométricas. Em aplicações de controle de acesso, um usuário pode ser coagido a se autenticar para permitir um acesso indevido. Como alternativa para este problema, a API utiliza um processo de autenticação contínua, que verifica se o usuário que se identificou no início de uma aplicação de software ainda está apto a continuar no sistema, sem interferências humanas ou paralisações do processo. Grande parte da literatura sobre projeto de sistemas biométricos tem o foco nas taxas de erro do sistema e na simplificação de equações. No entanto, também é importante que se tenha uma base sólida para progressos futuros no momento em que os processos e a arquitetura da nova aplicação biométrica estiverem sendo projetados. Neste sentido, a arquitetura projetada permitiu a construção de uma API bem definida para sistemas multibiométricos, que deverá auxiliar os desenvolvedores a padronizar, entre outras coisas, sua estrutura de dados, de forma a possibilitar e facilitar a fusão de modelos biométricos e a interoperabilidade. Deste modo, a API de segurança e armazenamento desenvolvida suporta uma arquitetura multibiométrica de controle de acesso para autenticação contínua extensível, isto é, capaz de receber novas características e processos biométricos com facilidade, permitindo, ainda, o uso de um mecanismo de segurança de templates biométricos. A API foi projetada e implementada. Sua demonstração foi feita através de uma aplicação protótipo, por meio da qual foi possível realizar os testes. Multibiometria Biometria Multimodalidade Controle de acesso Autenticação contínua Arquitetura de software Segurança de templates Multi-biometrics Biometrics Multimodality Access control Continuous authentication Software architecture Template security
152	Towards small scale sensors for turbulent flows and for rarefied gas damping Ebrahiminejad Rafsanjani, Amin 02 January 2018 (has links) This thesis makes contributions towards the development of two different small-scale sensing systems which show promise for measurements in fluid mechanics. Well-resolved turbulent Wall Shear Stress (WSS) measurements could provide a basis for realistic computational models of near-wall turbulent flow in aerodynamic design. In aerodynamics field applications, they could provide indication of flow direction and regions of separation, enabling inputs for flight control or active control of wind-turbine blades to reduce shock and fatigue loading due to separated flow regions. Traditional thermal WSS sensors consist of a single microscale hot-film, flush-mounted with the surface and maintained at constant temperature. Their potential for fast response to small fluctuations may not be realized, as heat transfer through the substrate creates heat-exchange with fluid, leading to loss of spatial and temporal resolution. The guard-heated thermal WSS sensor is a design introduced to block this loss of resolution. A numerical flow-field with a range of length and time and scales was generated to study the response of both guard-heated and conventional single-element thermal WSS sensors. A conjugate heat transfer solution including substrate heat conduction and flow convection, provides spatiotemporal data on both the actual and the “measured” WSS fluctuations calculated from the heat transfer rates experienced due to the WSS field. For a single-element sensor in air, we found that the heat transfer through the substrate was up to six times larger than direct heat transfer from the hot-film to the fluid. The resulting loss of resolution in the single-element sensor can be largely recovered by using the guard-heated design. Spectra for calculated WSS from heat transfer response show that high frequencies are considerably better resolved in guard-heated sensors than in the single element sensor. Nanoresonators are nanowires (NWs) excited into mechanical vibration at a resonance frequency, with a change in spectral width created by gas damping from the environment, or a shift in the resonance peak frequency created by added mass. They enable a wide range of applications, from sensors to study rarefied gas flow friction to the detection of early-stage cancer. The extraordinary sensitivity of nanoresonators for disease molecule detection has been demonstrated with a few NWs, but the high cost of traditional electron-beam lithography patterning, have inhibited practical applications requiring large arrays of sensors. Field-directed assembly techniques under development in our laboratory enable a large number of devices at low cost. Electro-deposition of metals in templates yields high-quality single nanowires, but undesired clumps must be removed. This calls for separation (extraction) of single nanowires. In this work, single nanowires are extracted by using the sedimentation behavior of particles. Based on numerical and experimental analyses, the optimum time and region for extracting samples with the highest fraction of single nanowires ratio was found. We show that it is possible to take samples free of large clumps of nanowires and decrease the ratio of undesired particles to single nanowires by over one order of magnitude. / Graduate turbulence fluctuations Wall shear stress Thermal sensors Thermal anemometry Large eddy simulations Wind turbine control systems Active flow control Separation of nanoparticles electrodeposition in templates Rhodium nanowires bidisperse suspension Nanowire fabrication
153	Proyecto Tracky Blanco Flores, Hermila Janet, Cabello Morales, Sandra Valeria, Gutierrez Cordova , Angela Ysabel, Pardave Guevara, Darly Giovanna, Izarra Soriano, Kevin Fernando 05 July 2021 (has links) Actualmente, estamos viviendo un tiempo de aceleración, donde los cambios son más frecuentes que lo habitual. Existen más máquinas y herramientas a nuestra disposición para mejorar nuestra calidad de vida, sin embargo, no tenemos el tiempo para terminar todas nuestras actividades. Nuestro modelo de negocio se basa en seguir apoyando a la transformación digital durante y post Covid-19, mediante unas plantillas descargables de una página web que te ayudará a organizar el tiempo, planear las actividades pendientes, pero en general a ser mucho más productivo y lograr cumplir todos tus proyectos, metas y objetivos de manera eficaz. Las plantillas digitales Tracky están en formato PDF editable que se adapta a cualquier dispositivo ya sea celular, Tablet o laptop. Asimismo, por parte de nuestra creatividad hemos creado un singular personaje que cobra vida en nuestras plantillas y redes sociales. Tracky, nuestro personaje principal, nació de la palabra tracker, una plantilla muy utilizada para realizar un buen seguimiento a tus actividades y que te ayudará ser una persona más organizada. ¿Estás listo(a) para vivir esta experiencia? / Nowadays, we are living in a time of acceleration, where changes are more frequent than usual. There are more machines and tools at our disposal to improve our quality of life, however, we do not have the time to finish all our activities. Our business model is based on continuing to support the digital transformation during and after Covid-19, through downloadable templates from a web page that will help you organize time, plan pending activities, but in general to be much more productive and achieve all your projects, goals, and objectives effectively. Tracky digital templates are in editable PDF format that adapts to any device, be it cell phone, tablet, or laptop. Also, through our creativity we have created a unique character that comes to life in our templates and social networks. Tracky, our main character, was born from the word tracker, a very used template to keep track of your activities and that will help you to be a more organized person. Are you ready to live this experience? / Trabajo de investigación Transformación digital Páginas web Plantillas digitales Plan de negocio Digital transformation Websites Digital templates Business plan
154	Online Course Completion Rates and Quality Matters Course Templates: A Causal-Comparative Study at a Midwestern Community College Mootispaw, Angel D. 05 May 2022 (has links) No description available. Community Colleges Community College Education Education Higher Education Instructional Design Community college Quality Matters online course templates online course completion rates quantitative causal-comparative distance education distance learning online learning
155	Transformace popisného jazyka mikroprocesoru do jazyka pro popis hardware / Transformation between the Microprocessor's Description Language and the Hardware Language Novotný, Tomáš January 2007 (has links) The Master's thesis Transformation of the microprocessor's description language to the hardware description language is aimed at design of application specific microprocessors with using ISAC language. It deals with design and implementation of transformation which converts description of microprocessor in ISAC language into equivalent description in VHDL language. The chapter Summary of research problems describes chosen problems, showing up some notions connected with problems and presents suggestion of transformation mentioned above. The chapter Suggestion of solution presents new extension of ISAC language. There is also described the way of design solution of transformation and solution of implementation of VHDL generator which performs transformation. Conclusion of thesis discusses next points of future work reached results.
156	Magnetization Reversal in Film-Nanostructure Architectures : Magnetization Reversal in Film-Nanostructure Architectures Schulze, Carsten 24 April 2014 (has links) The concept of percolated perpendicular media (PPM) for magnetic data storage is expected to surpass the areal storage density of 1 Tbit in -², which is regarded as the fundamental limit of conventional granular CoCrPt:oxide based recording media. PPM consist of a continuous ferromagnetic thin film with densely distributed defects acting as pinning sites for magnetic domain walls. In this study, practical realizations of PPM were fabricated by the deposition of [Co/Pt]8 multilayers with perpendicular magnetic anisotropy onto nanoperforated templates with various perforation diameters and periods. The structural defects given by the templates serve as pinning sites for the magnetic domain walls within the [Co/Pt]8 multilayers. Magnetometry at both the integral and the local level was employed to investigate the influence of the template on the magnetization reversal and the domain wall pinning. It was found, that magnetic domains can be pinned at the ultimate limit, between three adjacent pinning sites. The coercivity and the depinning field, which both are a measure for the strength of the magnetic domain wall pinning, were found to increase with increasing perforation diameter. The size of magnetic domains within the magnetic film appeared not to depend solely on the diameter of the nanoperforations or on the period of the template, but on the ration between diameter and period. By means of micromagnetic simulations it was found, that the presence of ferromagnetic material within the pinning site given supports the pinning of magnetic domain walls, compared to a pinning site that is solely given by a hole in the magnetic thin film. Investigation of the evolution of the magnetization in magnetic fields smaller than the coercive field revealed, that the energy barrier against thermally induced magnetization reversal is sufficiently large to provide long-term (> 10 years) stability of an arbitrary magnetization state. This could also be qualitatively supported by micromagnetic simulations. Static read/write tests with conventional hard disk recording heads revealed the possibility of imprinting bit patterns into the PPM under study. The minimum bit pitch that could be read back thereby depended on the period of the nanoperforated template. info:eu-repo/classification/ddc/538 ddc:538 Magnetismus ; Ummagnetisierung
157	DNA-Templated Nanomaterials Becerril-Garcia, Hector Alejandro 23 April 2007 (has links) (PDF) Nanomaterials display interesting physical and chemical properties depending on their shape, size and composition. Self assembly is an intriguing route to producing nanomaterials with controllable compositions and morphologies. DNA has been used to guide the self assembly of materials, resulting in: (1) metal nanowires; (2) metal or semiconductor nanorods; (3) carbon nanotubes; and (4) semiconductor, metal or biological nanoparticles. My work expands the range of DNA templated nanomaterials and develops novel ways of using DNA to pattern nanostructures on surfaces. I have performed the first synthesis of silver nanorods on single stranded DNA, an attractive material for localizing DNA coupled nanostructures through hybridization. I have demonstrated an ionic surface masking protocol to reduce ~70% of non specific metal deposition (a pervasive problem) during electroless plating of DNA with silver or copper. I have designed and constructed discrete three branched DNA junctions as scaffolding for self assembling three terminal, individually gateable nanotransistors. I have labeled these DNA structures with single streptavidin molecules, as a model for the placement of semiconductor nanocrystals at the junctions. Moreover, I have shown selective silver and copper plating of branched DNA constructs, with crystallinity that depends on plating conditions. I have fabricated DNA templated nickel nanostructures on surfaces and demonstrated their reversible interaction with a histidine labeled protein, as a model system for patterning histidine tagged nanostructures on surfaces. Previous methods were limited to decorating DNA scaffolds using streptavidin-biotin interactions. Finally, I have developed DNA shadow nanolithography, which uses angled thin film deposition and anisotropic etching to transfer patterns of surface aligned DNA onto substrates as nanoscale trenches with linewidths <30 nm. Nanotrenches can be post processed with microfabrication methods to modify their properties; I have constructed metal lines and nanopores from such trenches. This dissertation summarizes the principles and methods for synthesis and characterization of DNA templated nanomaterials. These biologically templated constructs may be useful in the fabrication of self assembled chemical and electrical sensors, and as structural materials for nanofabrication and nanopatterning on surfaces. DNA Nucleic Acids Macromolecules Molecular Templates Templated Nanofabrication Nanotechnology Nanocomposites Nanoparticles Metals Semiconductors Proteins Synthesis Characterization Electron Microscopy SEM TEM STEM X-ray analysis EDX Atomic Force Microscopy AFM Surfaces Materials Chemistry Biochemistry Chemistry
158	En studie av hur en webbapplikation för annonsering av konsultuppdrag till studenter kan implementeras för att uppfattas som användbar / A study of how a web application for advertising consulting jobs to students can be implemented to be perceived as useful Åström, Adam, Öberg, Albin, Elkjaer, Alice, Olsson, Fredrik, Bengtsson Malmborg, Hannes, Jacobson, Madeleine, Schwartz-Blicke, Oscar, Storsved, Viktor January 2021 (has links) Studentkonsultprojekt gör det möjligt för studenter att applicera sin kunskap i näringslivet samtidigt som det blir mindre kostsamt för företagen att anlita konsulter. Då jobbsökande via internet blir allt vanligare finns det ett behov av en webbapplikation för konsultuppdrag som kopplar samman studenter och företag. En av de viktigaste aspekterna för att skapa en konkurrenskraftig webbapplikation är användbarheten. Således är intentionen med denna studie att undersöka Hur kan en webbapplikation för konsultuppdrag mellan företag och studenter implementeras för att uppfattas som användbar av studenter? För att besvara frågeställningen har en webbapplikation för förmedling av konsulttjänster mellan företag och studenter utvecklats. Webbapplikationen baseras på en teoretisk grund där olika dimensioner av begreppet användbarhet analyserats. De dimensioner som lyfts är effektivitet, ändamålsenlighet och tillfredsställelse. I tillägg till detta har vikten av att specificera användare och de estetiska aspekternas påverkan på användbarhet behandlats. För att utvärdera om webbapplikationen upplevs som användbar testas den på tre testgrupper i tre olika skeden för att undersöka deras upplevelse av webbapplikationen. Testerna utgår från metoden thinking aloud tillsammans med enkäterna System Usability Scale (SUS) och Visual Aesthetics of Websites Inventory Short (VisAWI-S). SUS- och VisAWI-S-enkäterna gav indikationer på en starkt användbar applikation genom hela utvecklingsprocessen. Detta utifrån implementation av en design som främst utgick från principerna enkelhet och färgrikedom samt fokusområdena Synlighet av systemstatus, Igenkänning istället för återkallande, Flexibilitet och effektiv användning och Estetisk och minimalistisk design. Genom att analysera resultaten från thinking aloud-testerna kunde en tydlig minskning av negativa kommentarer identifieras mellan användartest 1-3. Utifrån dessa testresultat, dras slutsatserna att genom återkoppling relaterad till utförda aktioner, implementation av markörer och färgval med hänsyn till kontraster kan en webbapplikation för konsultjobb implementeras för att uppfattas som användbar av studenter. / Studentconsulting makes it possible for students to use their knowledge in business cases. In addition to this it also reduces the cost for enterprises when hiring consultants. As job hunting via the internet becomes more common there is a need for a web application that connects company projects with students who are interested in consulting. One of the most prominent aspects for a web application to be competitive is usability. The intention with this study is to examine How can a webapplication for consulting jobs between enterprises and students be implemented to be perceived as useful by students? To answer this question a web application for intermediation of consulting jobs between enterprises and students has been developed. The web application is developed on a theoretical basis where the different dimensions of the term usability has been analysed. These dimensions are efficiency, effectiveness and satisfaction. In addition to this the importance of specifying users and the aesthetic aspects effects on usability has been discussed. To evaluate if the web aplication is perceived as useful it is tested on three groups of people on three different occasions to examine their perception of the web application. The tests are based on the thinking aloud method together with the questionnaires System Usability Scale (SUS) and Visual Aesthetics of Websites Inventory Short (VisAWI-S). The SUS and VisAWI-S questionnaires indicated that the web application had a high level of usability throughout the development process. This was achieved through implementing a design based on simplicity and colorfulness as well as the principles Visibility of system status, Recognition rather than recall, Flexibility and efficiency of use and Aesthetic and minimalist design. By analysing the results from the thinking aloud tests a reduction in negative comments between test 1 and 3 could be identified. From the test results, the conclusion is that through responses related to completed actions, implementation of markers, and contrasting colors a web application for consulting jobs between enterprises and students can be implemented to be perceived as useful by students. Usability Design Single page application Web design Visual design Web application Web development HTML CSS JavaScript Python AJAX FLASK Templates JWT Job search Job Work efficiency navigation satisfaction expediency TDDD83 Användbarhet Användbar Design Webbutveckling HTML CSS JavaScript Python AJAX FLASK Templates JWT Jobbsökningssida Jobbsökning Jobb Arbete Plattform Webbapplikation Effektivitet Effektivt Navigerbarhet Ändamålsenlighet Tillfredsställelse TDDD83 Computer Engineering Datorteknik Human Computer Interaction Computer Sciences Datavetenskap (datalogi) Interaction Technologies Interaktionsteknik
159	Well-Formed and Scalable Invasive Software Composition / Wohlgeformte und Skalierbare Invasive Softwarekomposition Karol, Sven 26 June 2015 (has links) (PDF) Software components provide essential means to structure and organize software effectively. However, frequently, required component abstractions are not available in a programming language or system, or are not adequately combinable with each other. Invasive software composition (ISC) is a general approach to software composition that unifies component-like abstractions such as templates, aspects and macros. ISC is based on fragment composition, and composes programs and other software artifacts at the level of syntax trees. Therefore, a unifying fragment component model is related to the context-free grammar of a language to identify extension and variation points in syntax trees as well as valid component types. By doing so, fragment components can be composed by transformations at respective extension and variation points so that always valid composition results regarding the underlying context-free grammar are yielded. However, given a language’s context-free grammar, the composition result may still be incorrect. Context-sensitive constraints such as type constraints may be violated so that the program cannot be compiled and/or interpreted correctly. While a compiler can detect such errors after composition, it is difficult to relate them back to the original transformation step in the composition system, especially in the case of complex compositions with several hundreds of such steps. To tackle this problem, this thesis proposes well-formed ISC—an extension to ISC that uses reference attribute grammars (RAGs) to specify fragment component models and fragment contracts to guard compositions with context-sensitive constraints. Additionally, well-formed ISC provides composition strategies as a means to configure composition algorithms and handle interferences between composition steps. Developing ISC systems for complex languages such as programming languages is a complex undertaking. Composition-system developers need to supply or develop adequate language and parser specifications that can be processed by an ISC composition engine. Moreover, the specifications may need to be extended with rules for the intended composition abstractions. Current approaches to ISC require complete grammars to be able to compose fragments in the respective languages. Hence, the specifications need to be developed exhaustively before any component model can be supplied. To tackle this problem, this thesis introduces scalable ISC—a variant of ISC that uses island component models as a means to define component models for partially specified languages while still the whole language is supported. Additionally, a scalable workflow for agile composition-system development is proposed which supports a development of ISC systems in small increments using modular extensions. All theoretical concepts introduced in this thesis are implemented in the Skeletons and Application Templates framework SkAT. It supports “classic”, well-formed and scalable ISC by leveraging RAGs as its main specification and implementation language. Moreover, several composition systems based on SkAT are discussed, e.g., a well-formed composition system for Java and a C preprocessor-like macro language. In turn, those composition systems are used as composers in several example applications such as a library of parallel algorithmic skeletons. Software Komposition invasiv templates Meta-Programmierung Schnittstellen Code-Generierung generative Softwareentwicklung Java Syntaxbaum Parser Attributgrammariken Referenzattributgrammatiken CPP C-Preprocessor Aspektorientierte Programmierung Wohlgeformtheit abstrakter Syntaxgraph macros Expansion Kompilierer Programme statische Semantik BPMN Programmiersprachen domänenspezifische Sprachen Sprachkomposition C C++ invasive software composition component aspects weaving correct weaving well-formedness attribute grammars island grammars SkAT skeletons generative programming metaprogramming metamodeling Reuseware C C++ Java JastAdd JastAddJ Compilers RAG preprocessor macros decomposition code syntax tree graphs templates grammars context-sensitive context-free COMPOST EMFText JastEMF parsing expression grammars domain-specific languages BPMN embedded languages language composition ddc:004 rvk:ST 233
160	Well-Formed and Scalable Invasive Software Composition Karol, Sven 18 May 2015 (has links) Software components provide essential means to structure and organize software effectively. However, frequently, required component abstractions are not available in a programming language or system, or are not adequately combinable with each other. Invasive software composition (ISC) is a general approach to software composition that unifies component-like abstractions such as templates, aspects and macros. ISC is based on fragment composition, and composes programs and other software artifacts at the level of syntax trees. Therefore, a unifying fragment component model is related to the context-free grammar of a language to identify extension and variation points in syntax trees as well as valid component types. By doing so, fragment components can be composed by transformations at respective extension and variation points so that always valid composition results regarding the underlying context-free grammar are yielded. However, given a language’s context-free grammar, the composition result may still be incorrect. Context-sensitive constraints such as type constraints may be violated so that the program cannot be compiled and/or interpreted correctly. While a compiler can detect such errors after composition, it is difficult to relate them back to the original transformation step in the composition system, especially in the case of complex compositions with several hundreds of such steps. To tackle this problem, this thesis proposes well-formed ISC—an extension to ISC that uses reference attribute grammars (RAGs) to specify fragment component models and fragment contracts to guard compositions with context-sensitive constraints. Additionally, well-formed ISC provides composition strategies as a means to configure composition algorithms and handle interferences between composition steps. Developing ISC systems for complex languages such as programming languages is a complex undertaking. Composition-system developers need to supply or develop adequate language and parser specifications that can be processed by an ISC composition engine. Moreover, the specifications may need to be extended with rules for the intended composition abstractions. Current approaches to ISC require complete grammars to be able to compose fragments in the respective languages. Hence, the specifications need to be developed exhaustively before any component model can be supplied. To tackle this problem, this thesis introduces scalable ISC—a variant of ISC that uses island component models as a means to define component models for partially specified languages while still the whole language is supported. Additionally, a scalable workflow for agile composition-system development is proposed which supports a development of ISC systems in small increments using modular extensions. All theoretical concepts introduced in this thesis are implemented in the Skeletons and Application Templates framework SkAT. It supports “classic”, well-formed and scalable ISC by leveraging RAGs as its main specification and implementation language. Moreover, several composition systems based on SkAT are discussed, e.g., a well-formed composition system for Java and a C preprocessor-like macro language. In turn, those composition systems are used as composers in several example applications such as a library of parallel algorithmic skeletons. info:eu-repo/classification/ddc/004 ddc:004

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