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Proceedings ICPW'07: 2nd International Conference on the Pragmatic Web, 22-23 Oct. 2007, Tilburg: NL
Proceedings ICPW'07: 2nd International Conference on the Pragmatic Web, 22-23 Oct. 2007, Tilburg: N
Quality Goal Oriented Architectural Design and Traceability for Evolvable Software Systems
Softwaresysteme werden heute z.B. aufgrund sich ändernder Geschäftsprozesse
oder Technologien mit häufigen Veränderungen konfrontiert. Die Software und
speziell ihre Architektur muss diese Ă„nderungen zur dauerhaften Nutzbarkeit
ermöglichen.Während der Software-Evolution können Änderungen zu einer
Verschlechterung der Architektur fĂĽhren, der Architekturerosion. Dies
erschwert oder verhindert weitere Ă„nderungen wegen Inkonsistenz oder
fehlendem Programmverstehen. Zur Erosionsvermeidung müssen Qualitätsziele
wie Weiterentwickelbarkeit, Performanz oder Usability sowie die
Nachvollziehbarkeit von Architekturentwurfsentscheidungen berĂĽcksichtigt
werden. Dies wird jedoch oft vernachlässigt.Existierende Entwurfsmethoden
unterstützen den Übergang von Qualitätzielen zu geeigneten
Architekturlösungen nur unzureichend aufgrund einer Lücke zwischen Methoden
des Requirements Engineering und des Architekturentwurfs. Insbesondere gilt
dies fĂĽr Weiterentwickelbarkeit und die Nachvollziehbarkeit von
Entwurfsentscheidungen durch explizite Modellabhängigkeiten.Diese Arbeit
präsentiert ein neues Konzept, genannt Goal Solution Scheme, das
Qualitätsziele über Architekturprinzipien auf Lösungsinstrumente durch
explizite Abhängigkeiten abbildet. Es hilft somit, Architekturlösungen
entsprechend ihrem Einfluss auf Qualitätsziele auszuwählen. Das Schema wird
speziell hinsichtlich Weiterentwickelbarkeit diskutiert und ist in ein
zielorientiertes Vorgehen eingebettet, das etablierte Methoden und Konzepte
des Requirements Engineering und Architekturentwurfs verbessert und
integriert. Dies wird ergänzt durch ein Traceability-Konzept, welches einen
regelbasierten Ansatz mit Techniken des Information Retrieval verbindet.
Dies ermöglicht eine (halb-) automatische Erstellung von Traceability Links
mit spezifischen Linktypen und Attributen fĂĽr eine reichhaltige Semantik
sowie mit hoher Genauigkeit und Trefferquote.Die Realisierbarkeit des
Ansatzes wird an einer Fallstudie einer Software fĂĽr mobile Serviceroboter
gezeigt. Das Werkzeug EMFTrace wurde als eine erweiterbare Plattform
basierend auf Eclipse-Technologie implementiert, um die Anwendbarkeit der
Konzepte zu zeigen. Es integriert Entwurfsmodelle von externen CASE-Tools
mittels XML-Technologie in einem gemeinsamen Modell-Repository, wendet
Regeln zur Linkerstellung an und bietet Validierungsfunktionen fĂĽr Regeln
und Links.Today software systems are frequently faced with demands for changes, for
example, due to changing business processes or technologies. The software
and especially its architecture has to cope with those frequent changes to
permanently remain usable.During software evolution changes can lead to a
deterioration of the structure of software architectures called
architectural erosion, which hampers or even inhibits further changes
because of inconsistencies or lacking program comprehension. To support
changes and avoid erosion, especially quality goals, such as evolvability,
performance, or usability, and the traceability of design decisions have to
be considered during architectural design. This however often is
neglected.Existing design methods do not sufficiently support the
transition from the quality goals to appropriate architectural solutions
because there is still a gap between requirements engineering and
architectural design methods. Particularly support is lacking for the goal
evolvability and for the traceability of design decisions by explicit model
dependencies.This thesis presents a new concept called Goal Solution
Scheme, which provides a mapping from goals via architectural principles to
solution instruments by explicit dependencies. Thus it helps to select
appropriate architectural solutions according to their influence on quality
goals. The scheme is discussed especially regarding evolvability, and it is
embedded in a goal-oriented architectural design method, which enhances and
integrates established methods and concepts from requirements engineering
as well as architectural design. This is supplemented by a traceability
concept, which combines a rule-based approach with information retrieval
techniques for a (semi-) automated establishment of links with specific
link types and attributes for rich semantics and a high precision and
recall.The feasibility of the design approach has been evaluated in a case
study of a software platform for mobile robots. A prototype tool suite
called EMFTrace was implemented as an extensible platform based on Eclipse
technology to show the practicability of the thesis' concept. It integrates
design models from external CASE tools in a joint model repository by means
of XML technology, applies rules for link establishment, and provides
validation capabilities for rules and links
Advances in Grid Computing
This book approaches the grid computing with a perspective on the latest achievements in the field, providing an insight into the current research trends and advances, and presenting a large range of innovative research papers. The topics covered in this book include resource and data management, grid architectures and development, and grid-enabled applications. New ideas employing heuristic methods from swarm intelligence or genetic algorithm and quantum encryption are considered in order to explain two main aspects of grid computing: resource management and data management. The book addresses also some aspects of grid computing that regard architecture and development, and includes a diverse range of applications for grid computing, including possible human grid computing system, simulation of the fusion reaction, ubiquitous healthcare service provisioning and complex water systems
The 1989 Goddard Conference on Space Applications of Artificial Intelligence
The following topics are addressed: mission operations support; planning and scheduling; fault isolation/diagnosis; image processing and machine vision; data management; and modeling and simulation
Performance Observability and Monitoring of High Performance Computing with Microservices
Traditionally, High Performance Computing (HPC) softwarehas been built and deployed as bulk-synchronous, parallel
executables based on the message-passing interface (MPI) programming model.
The rise of data-oriented computing paradigms and an explosion
in the variety of applications that need to be supported on HPC
platforms have forced a re-think of the appropriate programming and execution models to integrate this new functionality.
In situ workflows demarcate a paradigm shift in
HPC software development methodologies enabling
a range of new applications ---
from user-level data services to machine learning (ML) workflows that run
alongside traditional scientific simulations.
By tracing the evolution of HPC software developmentover the past 30 years, this dissertation identifies the key elements and trends
responsible for the emergence of coupled, distributed, in situ workflows.
This dissertation's focus is on coupled in situ workflows
involving composable, high-performance microservices. After outlining the motivation
to enable performance observability of these services and why
existing HPC performance tools and techniques can not be applied in this context, this dissertation
proposes a solution wherein a set of techniques gathers, analyzes, and orients performance data from
different sources to generate observability. By leveraging microservice components initially designed
to build high performance data services,
this dissertation demonstrates their broader applicability for building and deploying performance
monitoring and visualization as services within an in situ workflow.
The results from this dissertation suggest that: (1) integration of
performance data from different sources is vital to understanding the performance
of service components, (2) the in situ (online) analysis of this performance data
is needed to enable the adaptivity of distributed components and manage monitoring data volume, (3) statistical modeling combined
with performance observations can help generate better service configurations, and (4) services are a promising
architecture choice for deploying in situ performance monitoring and visualization functionality.
This dissertation includes previously published and co-authored material and unpublished co-authored material
Information resources management, 1984-1989: A bibliography with indexes
This bibliography contains 768 annotated references to reports and journal articles entered into the NASA scientific and technical information database 1984 to 1989
Interoperability Gap Challenges for Learning Object Repositories & Learning Management Systems
An interoperability gap exists between Learning Management Systems (LMSs) and Learning Object Repositories (LORs). Learning Objects (LOs) and the associated Learning Object Metadata (LOM) that is stored within LORs adhere to a variety of LOM standards. A common LOM standard found in LORs is the Sharable Content Object Reference Model (SCORM) Content Aggregation Model (CAM). In contrast, LMSs are independent computer systems that manage and deliver course content to students via a web interface. This research addressed three important issues related to the interoperability gap: (a) a lack of a metadata standard that defined the format of how student assessment data should be communicated from LMSs to LORs, (b) a lack of an architectural standard for the movement of data from LMSs to LORs, and (c) a lack of middleware that facilitated the movement of the student assessment data from the LMSs to LORs. This research achieved the following objectives: (a) the SCORM CAM LOM standard was extended to facilitate the storage of student assessment data, (b) Service Oriented Architecture (SOA) was identified as the best architecture to resolve the interoperability gap between LMSs and LORs, (c) a panel of Computer Information Systems (CIS) experts participated in a five-stage, web-based, anonymous Delphi process that approved and ranked 28 functional requirements for a proposed middleware application, and (d) the functional requirements were verified via the development of a prototype that transferred student assessment data from a LMSs into the LOM of LOs that are stored within a LOR. In conclusion, the research demonstrated that there are three acceptable approaches to extending the SCORM LOM standard: (a) new metadata elements, (b) new vocabulary values, and (c) the reference of an internal or external XML file using a location element. The main accomplishments of the research were the gathering of SOA functional requirements and the development of a prototype that provided an approach for the resolution of the interoperability gap that exists between LMSs and LORs
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