Fotios Kokkoras

• Assistant Professor
• Professor (Assistant) at University of Thessaly

This systematic literature review explores current trends in automatic source code summarization and comprehension. Through extraction and analysis of information from six reputable digital libraries, we answered the following three questions: a) Which are the current machine learning models to generate summaries for source code? b) What factors sh...

Diabetic retinopathy (DR) is a common complication of long-term diabetes, affecting the human eye and potentially leading to permanent blindness. The early detection of DR is crucial for effective treatment, as symptoms often manifest in later stages. The manual grading of retinal images is time-consuming, prone to errors, and lacks patient-friendl...

Artificial Intelligence (in Greek). Η ύλη καλύπτει εκτενώς τόσο τη συμβολική όσο και την υπολογιστική τεχνητή νοημοσύνη και δεν παραλείπει να συμπεριλάβει και νέα θέματα μεγάλου ερευνητικού και εμπορικού ενδιαφέροντος. Αρκετά από αυτά καλύπτονται εκτενώς, κάνοντας το βιβλίο κατάλληλο για χρήση τόσο σε προπτυχιακά όσο και σε μεταπτυχιακά μαθήματα.

Sentiment analysis is a challenging task that attracted increasing interest during the last years. The availability of online data along with the business interest to keep up with consumer feedback generates a constant demand for online analysis of user-generated content. A key role to this task plays the utilization of domain-specific lexicons of...

The task of opinion mining has attracted interest during the last years. This is mainly due to the vast availability and value of opinions on-line and the easy access of data through conventional or intelligent crawlers. In order to utilize this information, algorithms make exten-sive use of word sets with known polarity. This approach is known as...

The task of opinion mining has attracted interest during the last years. This is mainly due to the vast availability and value of opinions on-line and the easy access of data through conventional or intelligent crawlers. In order to utilize this information, algorithms make extensive use of word sets with known polarity. This approach is known as d...

This application paper presents myVisitPlanner GR, an intelligent web-based system aiming at making recommendations that help visitors and residents of the region of Northern Greece to plan their leisure, cultural and other activities during their stay in this area. The system encompasses a rich ontology of activities, categorized across dimensions...

Web data extraction (or web scraping) is the process of collecting unstructured or semi-structured information from the World Wide Web, at different levels of automation. It is an important, valuable and practical approach towards web reuse while at the same time can serve the transition of the web to the semantic web, by providing the structured d...

Source code search engines assist the software development process by providing a way of searching for free source code in code repositories. Although their use is rather straightforward, there exist a few of them and the differences in the way they index and provide access to their assets require considerable time and effort from the programmer to...

in Greek

Product reviews written by on-line shoppers is a valuable source of information for potential new customers who desire to make an informed purchase decision. Manually processing quite a few dozens, or even hundreds, of reviews for a single product is tedious and time consuming. Although there exist mature and generic text summarization techniques,...

Researchers in the area of educational software have always shown great interest in the automatic synthesis of learning curricula. During the recent years, with the extensive use of metadata and the emergence of the Semantic Web, this vision is gradually turning into a reality. A number of systems for curricula synthesis have been proposed. These s...

The PASER Competencies Ontology is an RDF/S ontology, consisting of a number of AI-related competencies (310 in total) that formulate a taxonomy, deployed for the PASER (Planner for the Automatic Synthesis of Educational Resources) e-learning platform.

We use Conceptual Graphs (CGs) to model web content extraction rules (CG-Wrappers). The approach presented incorporates all major existing extraction techniques and allows the definition of synergies of cooperative wrappers for handling complex extraction task, without requiring programming.

This paper presents PASER, a system for automatically synthesizing curricula using AI Planning and Machine Learning techniques on an ontology of educational resources metadata. The ontology is a part–of hierarchy of learning themes which correspond to RDCEO competencies. The system uses an automated planner, which given the initial state of the pro...

This paper reports on the results of an ongoing project for the development of a platform for e-Learning, which automatically constructs curricula based on available educational resources and the learners needs and abilities. The system under development, called PASER (Planner for the Automatic Synthesis of Educational Resources), uses an automated...

Most internet stores selling certain types of products, usually offer a limited set of brand names and for each brand name, a limited set of products. In addition, the design of such e-commerce sites is strongly influenced by retailers whose only goal is to sell as many products as possible to the users that visit their site. As a result, such site...

In this paper, we propose the use of the Conceptual Graphs knowledge representation and reasoning formalism to model information extraction wrappers (CG-Wrappers). An information extraction wrapper is a mapping that populates a data repository with implicit objects that exist inside a given web page. Creating a wrapper, usually involves some traini...

One of the most rapidly evolving e-services is e-Learning, that is, the creation of advanced educational resources that are accessible on-line and, potentially, offer numerous advantages over the traditional ones like intelligent access, interoperability between two or more educational resources and adaptation to the user. The driving force behind...

An intelligent annotation-based video data model called Smart VideoText is introduced. It utilizes the conceptual graph knowledge representation formalism to capture the semantic associations among the concepts described in text annotations of video data. The aim is to achieve more effective query, retrieval, and browsing capabilities based on the...

Recently, several standardization efforts for e-learning technologies gave rise to various specifications for educational metadata, that is, data describing all the "entities" involved in an educational procedure. The internal details of systems that utilize these metadata are still an open issue since these efforts are primarily dealing with "what...

An intelligent annotation-based video data model called Smart VideoText is introduced. It utilizes the conceptual graph knowledge representation formalism to capture the semantic associations among the concepts described in text annotations of video data. The aim is to achieve more effective query, retrieval, and browsing capabilities based on the...

Recently, several standardization efforts for e-Learning technologies have given rise to various specifications for educational metadata, that is, data describing all the “entities” involved in an educational procedure. The internal details of systems that utilize these metadata are still an open issue since these efforts are primarily dealing with...

Two of the most important standardization efforts for e-learning technologies are related to the definition of metadata describing educational resources and metadata describ-ing the learner's profile. The internal details of systems that utilize these metadata is still an open issue since these efforts are primarily dealing with "what" and not "how...

Intelligent hypertext is a promising approach to information systems, because it combines the power of inference of expert systems and the intuitive power of hypertext. In this paper we propose the “COMFRESH”, a common framework for expert systems and hypertext. It is based on a Prolog interpreter and uses the conceptual graph knowledge representat...

The work presented in this paper concerns the ap-plication of CSPCONS, a distributed constraint logic programming platform to a workforce management problem, namely the BT-250-118 problem instance. The latter is a well-studied problem instance in which the requirement is to create sequences of job locations for the technicians to visit (tours), so...

Modern successful on-line shops and product compari-son sites allow consumers to express their opinion on products and services they purchased. Although such information can be useful to other potential customers, reading and mentally processing quite a few dozens or even hundreds of reviews for a single product is tedious and time consuming. In th...

One of the most rapidly evolving e-services is e-Learning, that is, the creation of advanced educational resources that are accessible on-line and, potentially, offer numerous advantages over the traditional ones like intelligent access, interoperability between two or more educational resources and adaptation to the user ((1), (2)). The driving fo...