15 research outputs found
Combining Textual and Visual Information for Image Retrieval in the Medical Domain
In this article we have assembled the experience obtained from our participation in the imageCLEF evaluation task over the past two years. Exploitation on the use of linear combinations for image retrieval has been attempted by combining visual and textual sources of images. From our experiments we conclude that a mixed retrieval technique that applies both textual and visual retrieval in an interchangeably repeated manner improves the performance while overcoming the scalability limitations of visual retrieval. In particular, the mean average precision (MAP) has increased from 0.01 to 0.15 and 0.087 for 2009 and 2010 data, respectively, when content-based image retrieval (CBIR) is performed on the top 1000 results from textual retrieval based on natural language processing (NLP)
Exploiting multiple sources of evidence for opinion search in the web
In this thesis we study Opinion Mining and Sentiment Analysis and propose
a ne-grained analysis of the opinions conveyed in texts. Concretely, the aim of
this research is to gain an understanding on how to combine di erent types of
evidence to e ectively determine on-topic opinions in texts. To meet this aim,
we consider content-match evidence, obtained at document and passage level,
as well as di erent structural aspects of the text.
Current Opinion Mining technology is not mature yet. As a matter of fact,
people often use regular search engines, which lack evolved opinion search ca-
pabilities, to nd opinions about their interests. This means that the e ort of
detecting what are the key relevant opinions relies on the user. The lack of
widely accepted Opinion Mining technology is due to the limitations of cur-
rent models, which are simplistic and perform poorly. In this thesis we study
a speci c set of factors that are indicative of subjectivity and relevance and we
try to understand how to e ectively combine them to detect opinionated docu-
ments, to extract relevant opinions and to estimate their polarity. We propose
innovative methods and models able to incorporate di erent types of evidence
and it is our intention to contribute in di erent areas, including those related
to i) search for opinionated documents, ii) detection of subjectivity at docu-
ment and passage level, and iii) estimation of polarity. An important concern
that guides this research is e ciency. Some types of evidence, such as discourse
structure, have only been tested with small collections from narrow domains
(e.g., movie reviews). We demonstrate here that evolved linguistic features {
based on discourse analysis{ can potentially lead to a better understanding of
how subjectivity
ows in texts. And we show that this type of features can be
e ciently injected into general-purpose opinion retrieval solutions that operate
at large scale
Knowledge representation and text mining in biomedical, healthcare, and political domains
Knowledge representation and text mining can be employed to discover new knowledge and develop services by using the massive amounts of text gathered by modern information systems. The applied methods should take into account the domain-specific nature of knowledge. This thesis explores knowledge representation and text mining in three application domains.
Biomolecular events can be described very precisely and concisely with appropriate representation schemes. Protein–protein interactions are commonly modelled in biological databases as binary relationships, whereas the complex relationships used in text mining are rich in information. The experimental results of this thesis show that complex relationships can be reduced to binary relationships and that it is possible to reconstruct complex relationships from mixtures of linguistically similar relationships. This encourages the extraction of complex relationships from the scientific literature even if binary relationships are required by the application at hand. The experimental results on cross-validation schemes for pair-input data help to understand how existing knowledge regarding dependent instances (such those concerning protein–protein pairs) can be leveraged to improve the generalisation performance estimates of learned models.
Healthcare documents and news articles contain knowledge that is more difficult to model than biomolecular events and tend to have larger vocabularies than biomedical scientific articles. This thesis describes an ontology that models patient education documents and their content in order to improve the availability and quality of such documents. The experimental results of this thesis also show that the Recall-Oriented Understudy for Gisting Evaluation measures are a viable option for the automatic evaluation of textual patient record summarisation methods and that the area under the receiver operating characteristic curve can be used in a large-scale sentiment analysis. The sentiment analysis of Reuters news corpora suggests that the Western mainstream media portrays China negatively in politics-related articles but not in general, which provides new evidence to consider in the debate over the image of China in the Western media
Text Extraction and Web Searching in a Non-Latin Language
Recent studies of queries submitted to Internet Search Engines have shown that
non-English queries and unclassifiable queries have nearly tripled during the
last decade. Most search engines were originally engineered for English. They
do not take full account of inflectional semantics nor, for example, diacritics or
the use of capitals which is a common feature in languages other than English.
The literature concludes that searching using non-English and non-Latin based
queries results in lower success and requires additional user effort to achieve
acceptable precision.
The primary aim of this research study is to develop an evaluation methodology
for identifying the shortcomings and measuring the effectiveness of
search engines with non-English queries. It also proposes a number of solutions
for the existing situation. A Greek query log is analyzed considering the morphological
features of the Greek language. Also a text extraction experiment
revealed some problems related to the encoding and the morphological and
grammatical differences among semantically equivalent Greek terms. A first
stopword list for Greek based on a domain independent collection has been
produced and its application in Web searching has been studied. The effect of
lemmatization of query terms and the factors influencing text based image retrieval
in Greek are also studied. Finally, an instructional strategy is presented
for teaching non-English students how to effectively utilize search engines.
The evaluation of the capabilities of the search engines showed that international
and nationwide search engines ignore most of the linguistic idiosyncrasies
of Greek and other complex European languages. There is a lack of
freely available non-English resources to work with (test corpus, linguistic resources,
etc). The research showed that the application of standard IR techniques,
such as stopword removal, stemming, lemmatization and query expansion,
in Greek Web searching increases precision.
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A commercial outcome prediction system for university technology transfer using neural networks
This thesis was submitted for the degree of Doctor of Philosophy and awarded by Brunel University, 26/03/2007.This thesis presents a commercial outcome prediction system (CPS) capable of predicting the likely future monetary return that would be generated by an invention. The CPS is designed to be used by university technology transfer offices for invention assessment purposes, and is based on the data from their historical invention cases. It is aimed at improving technology transfer offices' invention assessment performance. Using qualitative critical factors suggested by literature. a prototype CPS based on decision tree induction was developed. The prediction performance achieved by the prototype CPS was unreliable. Three surveys with various technology transfer offices were then performed, and the findings were incorporated into a final version of the CPS, which was based on neural networks. Subject to information obtained in the surveys, a number of potentially predictive attributes were proposed to form part of the predictor variables for the CPS. The CPS starts with a number of data reduction operations (based on principal component analysis and decision tree techniques), which identify the critical predictor variables. The CPS then uses five neural-network training algorithms to generate candidate classifiers, upon which the final classification is based. The prediction results achieved by the CPS were good and reliable. Additionally, the data reduction operations successfully captured the most discriminative invention attributes. The research demonstrated the potential or using the CPS for invention assessment. However, it requires sufficient historical data from the technology transfer office using it to provide accurate assessments.BruneI Universit
Factors Influencing Customer Satisfaction towards E-shopping in Malaysia
Online shopping or e-shopping has changed the world of business and quite a few people have
decided to work with these features. What their primary concerns precisely and the responses from
the globalisation are the competency of incorporation while doing their businesses. E-shopping has
also increased substantially in Malaysia in recent years. The rapid increase in the e-commerce
industry in Malaysia has created the demand to emphasize on how to increase customer satisfaction
while operating in the e-retailing environment. It is very important that customers are satisfied with
the website, or else, they would not return. Therefore, a crucial fact to look into is that companies
must ensure that their customers are satisfied with their purchases that are really essential from the ecommerce’s
point of view. With is in mind, this study aimed at investigating customer satisfaction
towards e-shopping in Malaysia. A total of 400 questionnaires were distributed among students
randomly selected from various public and private universities located within Klang valley area.
Total 369 questionnaires were returned, out of which 341 questionnaires were found usable for
further analysis. Finally, SEM was employed to test the hypotheses. This study found that customer
satisfaction towards e-shopping in Malaysia is to a great extent influenced by ease of use, trust,
design of the website, online security and e-service quality. Finally, recommendations and future
study direction is provided.
Keywords: E-shopping, Customer satisfaction, Trust, Online security, E-service quality, Malaysia
Proceedings of the Geodesy/Solid Earth and Ocean Physics (GEOP) Research Conferences
Papers are presented dealing with interdisciplinary research in the fields of geodesy, solid earth and ocean physics. Topics discussed include: solid earth and ocean tides; the rotation of the earth and polar motion; vertical crustal motions; the geoid and ocean surface; earthquake mechanism; sea level changes; and lunar dynamics
2008-2009 Louisiana Tech University Catalog
The Louisiana Tech University Catalog includes announcements and course descriptions for courses offered at Louisiana Tech University for the academic year of 2008-2009.https://digitalcommons.latech.edu/university-catalogs/1006/thumbnail.jp