11,680 research outputs found
Recommended from our members
Multi agent system for web database processing, on data extraction from online social networks.
In recent years, there has been a
ood of continuously changing information
from a variety of web resources such as web databases, web sites,
web services and programs. Online Social Networks (OSNs) represent
such a eld where huge amounts of information are being posted online
over time. Due to the nature of OSNs, which o er a productive source
for qualitative and quantitative personal information, researchers from
various disciplines contribute to developing methods for extracting data
from OSNs. However, there is limited research which addresses extracting
data automatically. To the best of the author's knowledge, there
is no research which focuses on tracking the real time changes of information
retrieved from OSN pro les over time and this motivated the
present work.
This thesis presents di erent approaches for automated Data Extraction
(DE) from OSN: crawler, parser, Multi Agent System (MAS) and Application
Programming Interface (API). Initially, a parser was implemented
as a centralized system to traverse the OSN graph and extract the pro-
le's attributes and list of friends from Myspace, the top OSN at that
time, by parsing the Myspace pro les and extracting the relevant tokens
from the parsed HTML source les. A Breadth First Search (BFS) algorithm
was used to travel across the generated OSN friendship graph
in order to select the next pro le for parsing. The approach was implemented
and tested on two types of friends: top friends and all friends.
In case of top friends, 500 seed pro les have been visited; 298 public
pro les were parsed to get 2197 top friends pro les and 2747 friendship
edges, while in case of all friends, 250 public pro les have been parsed
to extract 10,196 friends' pro les and 17,223 friendship edges.
This approach has two main limitations. The system is designed as
a centralized system that controlled and retrieved information of each
user's pro le just once. This means that the extraction process will stop
if the system fails to process one of the pro les; either the seed pro le
( rst pro le to be crawled) or its friends. To overcome this problem,
an Online Social Network Retrieval System (OSNRS) is proposed to
decentralize the DE process from OSN through using MAS. The novelty
of OSNRS is its ability to monitor pro les continuously over time.
The second challenge is that the parser had to be modi ed to cope with
changes in the pro les' structure. To overcome this problem, the proposed
OSNRS is improved through use of an API tool to enable OSNRS
agents to obtain the required elds of an OSN pro le despite modi cations
in the representation of the pro le's source web pages. The experimental
work shows that using API and MAS simpli es and speeds up the
process of tracking a pro le's history. It also helps security personnel,
parents, guardians, social workers and marketers in understanding the
dynamic behaviour of OSN users. This thesis proposes solutions for web
database processing on data extraction from OSNs by the use of parser
and MAS and discusses the limitations and improvements.Taibah Universit
Knowledge Representation with Ontologies: The Present and Future
Recently, we have seen an explosion of interest in ontologies as
artifacts to represent human knowledge and as critical components in
knowledge management, the semantic Web, business-to-business
applications, and several other application areas. Various research
communities commonly assume that ontologies are the appropriate modeling
structure for representing knowledge. However, little discussion has
occurred regarding the actual range of knowledge an ontology can
successfully represent
Proceedings of the ECCS 2005 satellite workshop: embracing complexity in design - Paris 17 November 2005
Embracing complexity in design is one of the critical issues and challenges of the 21st century. As the realization grows that design activities and artefacts display properties associated with complex adaptive systems, so grows the need to use complexity concepts and methods to understand these properties and inform the design of better artifacts. It is a great challenge because complexity science represents an epistemological and methodological swift that promises a holistic approach in the understanding and operational support of design. But design is also a major contributor in complexity research. Design science is concerned with problems that are fundamental in the sciences in general and complexity sciences in particular. For instance, design has been perceived and studied as a ubiquitous activity inherent in every human activity, as the art of generating hypotheses, as a type of experiment, or as a creative co-evolutionary process. Design science and its established approaches and practices can be a great source for advancement and innovation in complexity science. These proceedings are the result of a workshop organized as part of the activities of a UK government AHRB/EPSRC funded research cluster called Embracing Complexity in Design (www.complexityanddesign.net) and the European Conference in Complex Systems (complexsystems.lri.fr). Embracing complexity in design is one of the critical issues and challenges of the 21st century. As the realization grows that design activities and artefacts display properties associated with complex adaptive systems, so grows the need to use complexity concepts and methods to understand these properties and inform the design of better artifacts. It is a great challenge because complexity science represents an epistemological and methodological swift that promises a holistic approach in the understanding and operational support of design. But design is also a major contributor in complexity research. Design science is concerned with problems that are fundamental in the sciences in general and complexity sciences in particular. For instance, design has been perceived and studied as a ubiquitous activity inherent in every human activity, as the art of generating hypotheses, as a type of experiment, or as a creative co-evolutionary process. Design science and its established approaches and practices can be a great source for advancement and innovation in complexity science. These proceedings are the result of a workshop organized as part of the activities of a UK government AHRB/EPSRC funded research cluster called Embracing Complexity in Design (www.complexityanddesign.net) and the European Conference in Complex Systems (complexsystems.lri.fr)
Conceptual graph-based knowledge representation for supporting reasoning in African traditional medicine
Although African patients use both conventional or modern and traditional healthcare simultaneously, it has been proven that 80% of people rely on African traditional medicine (ATM). ATM includes medical activities stemming from practices, customs and traditions which were integral to the distinctive African cultures. It is based mainly on the oral transfer of knowledge, with the risk of losing critical knowledge. Moreover, practices differ according to the regions and the availability of medicinal plants. Therefore, it is necessary to compile tacit, disseminated and complex knowledge from various Tradi-Practitioners (TP) in order to determine interesting patterns for treating a given disease. Knowledge engineering methods for traditional medicine are useful to model suitably complex information needs, formalize knowledge of domain experts and highlight the effective practices for their integration to conventional medicine. The work described in this paper presents an approach which addresses two issues. First it aims at proposing a formal representation model of ATM knowledge and practices to facilitate their sharing and reusing. Then, it aims at providing a visual reasoning mechanism for selecting best available procedures and medicinal plants to treat diseases. The approach is based on the use of the Delphi method for capturing knowledge from various experts which necessitate reaching a consensus. Conceptual graph formalism is used to model ATM knowledge with visual reasoning capabilities and processes. The nested conceptual graphs are used to visually express the semantic meaning of Computational Tree Logic (CTL) constructs that are useful for formal specification of temporal properties of ATM domain knowledge. Our approach presents the advantage of mitigating knowledge loss with conceptual development assistance to improve the quality of ATM care (medical diagnosis and therapeutics), but also patient safety (drug monitoring)
Social and Semantic Contexts in Tourist Mobile Applications
The ongoing growth of the World Wide Web along with the increase possibility of access information through a variety of devices in mobility, has defi nitely changed the way users acquire, create, and personalize information, pushing innovative strategies for annotating and organizing it.
In this scenario, Social Annotation Systems have quickly gained a huge popularity, introducing millions of metadata on di fferent Web resources following a bottom-up approach, generating free and democratic mechanisms of classi cation, namely folksonomies. Moving away from hierarchical classi cation schemas, folksonomies represent also a meaningful mean for identifying similarities among users, resources and tags. At any rate, they suff er from several limitations, such as the lack of specialized tools devoted to manage, modify, customize and visualize them as well as the lack of an explicit semantic, making di fficult for users to bene fit from them eff ectively. Despite appealing promises of Semantic Web technologies, which were intended to explicitly formalize the knowledge within a particular domain in a top-down manner, in order to perform intelligent integration and reasoning on it, they are still far from reach their objectives, due to di fficulties in knowledge acquisition and annotation bottleneck.
The main contribution of this dissertation consists in modeling a novel conceptual framework that exploits both social and semantic contextual dimensions, focusing on the domain of tourism and cultural heritage. The primary aim of our assessment is to evaluate the overall user satisfaction and the perceived quality in use thanks to two concrete case studies. Firstly, we concentrate our attention on contextual information and navigation, and on authoring tool; secondly, we provide a semantic mapping of tags of the system folksonomy, contrasted and compared to the expert users' classi cation, allowing a bridge between social and semantic knowledge according to its constantly mutual growth.
The performed user evaluations analyses results are promising, reporting a high level of agreement on the perceived quality in use of both the applications and of the speci c analyzed features, demonstrating that a social-semantic contextual model improves the general users' satisfactio
- âŠ