8 research outputs found
A Taxonomy Of Aspect-Oriented Security
Aspect-Oriented Programming is gaining prominence, particularly in the area of security. There are however no taxonomies available, that classify the proliferation of research done in the area of Aspect-Oriented Security. This paper attempts to categorize research outputs conducted in this area, and evaluate the usability of the aspect-oriented paradigm in terms of software security
Interim research assessment 2003-2005 - Computer Science
This report primarily serves as a source of information for the 2007 Interim Research Assessment Committee for Computer Science at the three technical universities in the Netherlands. The report also provides information for others interested in our research activities
Supporting Management lnteraction and Composition of Self-Managed Cells
Management in ubiquitous systems cannot rely on human intervention or centralised
decision-making functions because systems are complex and devices
are inherently mobile and cannot refer to centralised management applications
for reconfiguration and adaptation directives. Management must be devolved,
based on local decision-making and feedback control-loops embedded in autonomous
components. Previous work has introduced a Self-Managed Cell (SMC)
as an infrastructure for building ubiquitous applications. An SMC consists
of a set of hardware and software components that implement a policy-driven
feedback control-loop. This allows SMCs to adapt continually to changes in
their environment or in their usage requirements. Typical applications include
body-area networks for healthcare monitoring, and communities of unmanned
autonomous vehicles (UAVs) for surveillance and reconnaissance operations.
Ubiquitous applications are typically formed from multiple interacting autonomous
components, which establish peer-to-peer collaborations, federate and
compose into larger structures. Components must interact to distribute management
tasks and to enforce communication strategies. This thesis presents
an integrated framework which supports the design and the rapid establishment
of policy-based SMC interactions by systematically composing simpler abstractions
as building elements of a more complex collaboration. Policy-based
interactions are realised – subject to an extensible set of security functions –
through the exchanges of interfaces, policies and events, and our framework
was designed to support the specification, instantiation and reuse of patterns of
interaction that prescribe the manner in which these exchanges are achieved.
We have defined a library of patterns that provide reusable abstractions for
the structure, task-allocation and communication aspects of an interaction,
which can be individually combined for building larger policy-based systems in
a methodical manner. We have specified a formal model to ensure the rigorous
verification of SMC interactions before policies are deployed in physical devices.
A prototype has been implemented that demonstrates the practical feasibility
of our framework in constrained resources
A semantic framework for event-driven service composition
Title from PDF of title page, viewed on September 14, 2011VitaDissertation advisor: Yugyung LeeIncludes bibliographical references (p. 289-329)Thesis (Ph.D)--School of Computing and Engineering. University of Missouri--Kansas City, 2011Service Oriented Architecture (SOA) has become a popular paradigm for designing
distributed systems where loosely coupled services (i.e. computational entities) can be
integrated seamlessly to provide complex composite services. Key challenges are discovery
of the required services using their formal descriptions and their coherent composition in a
timely manner. Most service descriptions are written in XML-based languages that are
syntactic, creating linguistic ambiguity during service matchmaking. Furthermore, existing
models that implement SOA have mostly middleware-controlled synchronous request/replybased
runtime binding of services that incur undesirable service latency. In addition, they
impose expensive state monitoring overhead on the middleware. Some newer event-driven
models introduce asynchronous publish/subscribe-based event notifications to consumer
applications and services. However, they require an event-library that stores definitions of
all possible system events, which is impractical in an open and dynamic system. The objective of this study is to efficiently address on-demand consumer requests
with minimum service latency and maximum consumer utility. It focuses on semantic eventdriven
service composition. For efficient semantic service discovery, the dissertation
proposes a novel service learning algorithm called Semantic Taxonomic Clustering (STC). The algorithm utilizes semantic service descriptions to cluster services into functional
categories for pruning search space during service discovery and composition. STC utilizes
a dynamic bit-encoding algorithm called DL-Encoding that enables linear time bit operationbased
semantic matchmaking as compared to expensive reasoner-based semantic
matchmaking. The algorithm shows significant improvement in performance and accuracy
over some of the important service category algorithms reported in the literature. A novel
user-friendly and computationally efficient query model called Desire-based Query
Model (DQM) is proposed for formally specifying service queries. STC and DQM serve as
the building block for the dual framework that is the core contribution of this dissertation: (i)
centralized ALNet (Activity Logic Network) platform and (ii) distributed agentbased
SMARTSPACE platform. The former incorporates a middleware controlled service
composition algorithm called ALNetComposer while the latter includes the SmartDeal
purely distributed composition algorithm. The query response accuracy and performance
were evaluated for both the algorithms under simulated event-driven SOA environments.
The experimental results show that various environmental parameters, such as domain
diversity and scope, size and complexity of the SOA system, and dynamicity of the SOA system, significantly affect accuracy and performance of the proposed model. This
dissertation demonstrates that the functionality and scalability of the proposed framework
are acceptable for relatively static and domain specific environments as well as large,
diverse, and highly dynamic environments. In summary, this dissertation addresses the key
design issues and problems in the area of asynchronous and pro-active event-driven service
composition.Introduction -- Research background -- Semantic service matchmaking & query modeling -- Service organization by learning service category -- ALNet: event-driven platform for service composition -- SMARTSPACE: distributed multi-agent based event-handeling -- Conclusion & future wor
Abstraction over non-local object information in aspect-oriented programming using path expression pointcuts
Aspect-oriented software development (AOSD) consists of a number of technologies that promise a better level of modularization of concerns
that cannot be separated in individual modules by using conventional
techniques. Aspect-oriented programming (AOP) is one of these technologies. It allows the modularization at the level of software
application code. It provides programmers with means to quantify over specific points in the base application code, called join points, at which the crosscutting concern code must be triggered. The quantification is achieved by special selection constructs called pointcuts, while the triggered code that is responsible for adapting the selected join point is provided by special construct called advice. The selection and adaptation mechanisms in aspect-oriented programming depend heavily on the distinguishing properties of the join points. These properties can either be derived from the local execution context at the join point or they are considered to be non-local to the join point. Aspect-oriented systems provide a plenty of pointcut constructs that support accessing the local join point properties, while they rarely support the non-local properties.
A large research effort has been achieved to extend current aspectoriented systems in order to solve the problem of non-locality. However, none of these proposals support the non-local object relationships. There are many situations where a good abstraction over nonlocal object information is needed, otherwise, the developers will be obliged to provide complex and error-prone workarounds inside advice body that conceptually do not reflect the semantics of join point selection and mix it with the semantics of join point daptation. Such recurrent situations occur when trying to modularize the object persistence concern. Object persistence, the process of storing and retrieving objects to and from the datastore, is a classical example of crosscutting concern. Orthogonal object persistence meets the obliviousness property of AOP: The base code should not be prepared upfront for persistence. This thesis addresses the shortcomings in current aspect-oriented persistence systems. It shows that the reason for such shortcomings is due to the lack of supporting non-local object information by the used aspect-oriented languages. To overcome this problem, this thesis proposes a new extension to the current pointcut languages called path expression pointcuts that operate on object graphs and make relevant object information available to the aspects. As an explicit and complete construct, a formal semantics and type system have provided. Moreover, an implementation of path expression pointcuts is discussed in the thesis along with its usage to show how the aforementioned problems are resolved
Automatic extraction of robotic surgery actions from text and kinematic data
The latest generation of robotic systems is becoming increasingly autonomous due to technological advancements and artificial intelligence. The medical field, particularly surgery, is also interested in these technologies because automation would benefit surgeons and patients. While the research community is active in this direction, commercial surgical robots do not currently operate autonomously due to the risks involved in dealing with human patients: it is still considered safer to rely on human surgeons' intelligence for decision-making issues. This means that robots must possess human-like intelligence, including various reasoning capabilities and extensive knowledge, to become more autonomous and credible. As demonstrated by current research in the field, indeed, one of the most critical aspects in developing autonomous systems is the acquisition and management of knowledge. In particular, a surgical robot must base its actions on solid procedural surgical knowledge to operate autonomously, safely, and expertly. This thesis investigates different possibilities for automatically extracting and managing knowledge from text and kinematic data. In the first part, we investigated the possibility of extracting procedural surgical knowledge from real intervention descriptions available in textbooks and academic papers on the robotic-surgical domains, by exploiting Transformer-based pre-trained language models. In particular, we released SurgicBERTa, a RoBERTa-based pre-trained language model for surgical literature understanding. It has been used to detect procedural sentences in books and extract procedural elements from them. Then, with some use cases, we explored the possibilities of translating written instructions into logical rules usable for robotic planning. Since not all the knowledge required for automatizing a procedure is written in texts, we introduce the concept of surgical commonsense, showing how it relates to different autonomy levels. In the second part of the thesis, we analyzed surgical procedures from a lower granularity level, showing how each surgical gesture is associated with a given combination of kinematic data