Τα συστήματα διαχείρισης περιεχομένου εξελίσσονται συνεχώς προσφέροντας περισσότερες και πολυπλοκότερες υπηρεσίες προς τους χρήστες/διαχειριστές. Παράλληλα, πλήθος σχεδιαστικών τεχνικών και σύγχρονων τεχνολογιών, που έχουν προταθεί από την παγκόσμια ερευνητική κοινότητα, φαίνεται να κερδίζουν έδαφος στην υλοποίηση τέτοιων συστημάτων, προκειμένου να αντιμετωπιστούν θέματα όπως είναι η μεταφορά ψηφιακών δεδομένων και η ευελιξία στην υλοποίηση επιχειρησιακών λογικών. Αυτό έχει ως αποτέλεσμα τη βελτίωση των διαδικασιών παραμετροποίησης, με τέτοιο τρόπο ώστε να δίνεται η δυνατότητα στους προγραμματιστές και σχεδιαστές εφαρμογών να χρησιμοποιούν ποιοτικά και αποδοτικά APIs και προγραμματιστικές τεχνικές. Επιπρόσθετα, τα οφέλη της χρήσης των προτύπων και τεχνικών είναι εμφανή στην ανάπτυξη βοηθητικών εργαλείων, την επίλυση κοινών προβλημάτων και την επικοινωνία μεταξύ διαφορετικών συστημάτων διαχείρισης περιεχομένου. Στα πλαίσια αυτής της διπλωματικής εργασίας μελετούνται σχεδιαστικές αρχές, πρότυπα και προγραμματιστικές τεχνικές, οι οποίες εφαρμόζονται για την υλοποίηση ευρέως διαδεδομένων συστημάτων διαχείρισης περιεχομένου. Απώτερος στόχος είναι η ανάδειξη θεμάτων σχετικών με τις τεχνικές διαχείρισης πληροφορίας που έχουν εφαρμοστεί και η αξιολόγηση των εργαλείων που έχουν αναπτυχθεί σε σύγχρονα συστήματα διαχείρισης περιεχομένου, όπως είναι το Drupal, το Documentum και το Alfresco. Επιπλέον, υλοποιείται σύστημα για την επίτευξη επικοινωνίας του Drupal με απομακρυσμένο αποθηκευτικό χώρο, μέσω Web Services. Με αυτό τον τρόπο προτείνεται περιβάλλον ικανό να χειριστεί πληροφορία εκτός του συστήματος του Drupal και αναδεικνύεται η σπουδαιότητα της αρθρωτής αρχιτεκτονικής και της επεξεργασίας περιεχομένου σε υποσυστήματα διαφορετικών εξυπηρετητών. Στα πλαίσια της υλοποίησης αυτής χρησιμοποιήθηκαν τεχνολογίες και γλώσσες προγραμματισμού php, XHTML, Javascript, AJAX για τα modules και την παρουσίαση σε περιβάλλον Drupal, EJBs και JPA για την υλοποίηση της επιχειρησιακής λογικής και των Web Services σε ξεχωριστό εξυπηρετητή. / The evolution of the Content Management systems provides more complex services towards users. In parallel, various design patterns and modern technologies, which are suggested by the scientific community, are implemented for these systems, in order to confront issues such as digital data transportation and implementation of business logic. As a result, the system developers and designers of the applications are able to configure the system via a sophisticated environment with APIs and using modern programming techniques and technologies. In addition, the benefits we gain using standards and techniques appear during the process of developing new tools, the communication between different Content Management Systems and on solving common problems. This essay focuses on various design patterns, programming techniques and standards, which apply in implementing famous Content Management Systems. Our main goal is the suggestion of issues related to the content management techniques and the evaluation of tools, which are used by the modern Content Management Systems, such as Drupal, Documentum and Alfresco. Eventually, a system was implemented, which concerns the communication between the Drupal and a remote repository. More specifically, Web Services, Database with useful material and several Drupal modules were designed and implemented. The main purpose of this approach is the suggestion of a sophisticated environment, in order to manage information out of the Drupal repository, using the benefits of modular architecture. The technologies that were used for the implementation on Drupal environment were PHP, XHTML, Javascript, AJAX and for the implementation of the remote system were EJBs, JPA and Web Services (Proxy, Business Services).

This thesis presents Illusion SDK: a general, extensible framework for augmented reality (AR) applications. Illusion provides loosely coupled or decoupled abstractions of sensors, trackers, and compositors. Implementations are optimized for particular use cases. Illusion’s architecture depends on only an event system and a 3D scene graph, so it is highly portable. Wrapping of third-party trackers is supported. Illusion’s current implementation targets Flash 11.4 and integrates with the Alternativa3D 8 graphics engine. To our knowledge, Illusion’s support for wrapping third-party trackers is unique among toolkits targeting the GPU-accelerated Web. Illusion performs well on MacBook Pro 13" mid-2010, where an intensive camera application can exceed 45 FPS. Generally, Illusion should perform well on hardware that uses shared video memory. Optimizations are needed for hardware that uses dedicated video memory. These optimizations are problematic in Flash 11.4 but should not generally be problematic in ports to other platforms.

Business processes describe a set of tasks for accomplishing business objectives of an organization. Business applications automate business processes to improve the productivity of business users. Nowadays, the business environment changes fast due to rapid market growth and technological innovations. Business processes are continuously updated to reflect new business initiatives. Business applications are frequently evolved to add features to meet new requirements and fix defects. Quite often, business processes and business applications evolve independently without direct reference to each other. Over time, it becomes more and more challenging to maintain the consistency between a business application and the corresponding business processes. Moreover, the existing development approaches rely on software developers’ craftsmanship to design and implement business applications. Such a development paradigm is inefficient and leads to inconsistency between business processes and business applications. To facilitate the alignment between business applications and business processes, we present an approach that automatically generates software architecture and code skeletons of business applications from business processes. We identify architectural components from business processes by analyzing dependencies among tasks. To verify the achievement of quality requirements, we extend a set of existing product metrics to automatically evaluate the quality of the generated software architecture designs. Eventually, we apply refactoring strategies, such as software architectural styles or design patterns, to optimize the generated software architecture designs and resolve identified quality problems. Moreover, we also present an approach to automatically refine software architecture to design models and code skeletons of business applications. The effectiveness of our proposed approach is illustrated through case studies. / Thesis (Ph.D, Electrical & Computer Engineering) -- Queen's University, 2011-01-30 00:06:34.77

Depending on the role of software in everyday life, the cost of a software failure can sometimes be unaffordable. During system execution, errors may occur in system components and failures may be manifested due to these errors. These errors differ with respect to their effects on system behavior and consequent failure manifestation manners. Predicting failures before their manifestation is important to assure system resilience. It helps avoid the cost of failures and enables systems to perform corrective actions prior to failure occurrences. However, effective runtime error detection and failure prediction techniques encounter a prohibitive challenge with respect to the control flow representation of large software systems with intricate control flow structures. In this thesis, we provide a technique for failure prediction from runtime errors of large software systems. Aiming to avoid the possible difficulties and inaccuracies of the existing Control Flow Graph (CFG) structures, we first propose a Connection Dependence Graph (CDG) for control flow representation of large software systems. We describe the CDG structure and explain how to derive it from program source code. Second, we utilize the proposed CDG to provide a connection-based signature approach for control flow error detection. We describe the monitor structure and present the error checking algorithm. Finally, we utilize the detected errors and erroneous state parameters to predict failure occurrences and modes during system runtime. We craft runtime signatures based on these errors and state parameters. Using system error and failure history, we determine a predictive function (an estimator) for each failure mode based on these signatures. Our experimental evaluation for these techniques uses a large open-source software (PostgreSQL 8.4.4 database system). The results show highly efficient control flow representation, error detection, and failure prediction techniques. This work contributes to software reliability by providing a simple and accurate control flow representation and utilizing it to detect runtime errors and predict failure occurrences and modes with high accuracy. / Thesis (Ph.D, Computing) -- Queen's University, 2012-09-25 23:44:12.356

A need has arisen for an easy-to-use, flexible, transparent, and cross-platform communication backbone for configuration and execution of distributed simulations and experiments. Open source, open architecture, and custom student written pro- grams have extended the capabilities of educational research facilities and opened the way for the development of the architecture presented in this thesis. The architecture is known by the recursive acronym hADES: hADES Architecture for Distributed Engineering Simulation. Included in this thesis is a discussion of the design and implementation of the novel hADES software architecture for Ethernet and wireless IEEE 802.11 network-based distributed simulation and experiment facilities. The goal of this architecture is to facilitate rapid integration of new and legacy simulations and laboratory equipment to support undergraduate and graduate research projects as well as educational classroom activities and industrial simulation and experiments.

Software has been studied at a variety of granularities. Code, classes, groups of classes, programs and finally large scale applications have been examined in detail. What lies beyond is the study of software collections that group together many individual applications. Collecting software and distributing it via a central repository has been popular for a while in the open source world, and only recently caught on commercially with Apple’s Mac app store and Microsoft’s Windows store. In many of these software collections, there is normally a complex process that must be followed in order to fully integrate new applications into the system. Moreover, in the case of open source software collections, applications frequently rely on each other for functionality and their interactions can be complex. We know that there are thousands of applications in these software collections that people depend on worldwide, but research in this area has been limited compared to other areas and granularities of software. In this thesis, we explore the evolution and architecture of a large open source software collections by using Debian as a case study. Debian is a software collection based off the Linux kernel with a large number of packages spread over multiple hardware platforms. Each package provides a particular service or application and is actively maintained by one or more developers. This thesis investigates how these packages evolve through time and their interactions with one another. The first half of the thesis describes the life cycle of a package from inception to end by carrying out a longitudinal study using the Ultimate Debian Database (UDD). The birth of packages is examined to see how Debian is growing. Conversely, package death is also analyzed to determine the lifespan of these packages. Moreover, four different package attributes are examined. They are package age, package bugs, package maintainers and package popularity. These four attributes combine to give us the overall biography of Debian packages. Debian’s architecture is explored in the second part of the thesis, where we analyze how packages interact with each other by examining the package dependencies in detail. The dependencies within Debian are extensive, which makes for an interesting architecture, but they are complex to analyze. This thesis provides a close look at the layered pattern. This pattern categorizes each package into one of five layers based on how they are used. These layers may also be visualized to give a concise view of how an application is structured. Using these views, we define five architectural subpatterns and anti-subpatterns which can aid developers in creating and maintaining packages.

Thesis (Ph. D.)--University of Washington, 2004. / Vita. Includes bibliographical references (p. 149-157).

Thesis (M. S. in Computer Science)--Vanderbilt University, May 2005. / Title from title screen. Includes bibliographical references.

Title from first page of PDF document. Includes bibliographical references (p. Xx-Xx).

Thesis (Ph.D.)--Mississippi State University. Department of Computer Science and Engineering. / Title from title screen. Includes bibliographical references.