Hilal Tarakçı Multimedia and semantic web
Ali Anıl Sınacı
1. Yakup Yildirim Formalizing Workflows Using the Event Calculus, 2000
The event calculus is a logic programming formalism for representing events and their effects especially in database applications. This thesis presents the use of the event calculus for specifying and simulating workflows. The proposed framework maintains a representation of the dynamic world being modeled on the basis of user supplied axioms about preconditions and effects of events and the initial state of the world. The net effect is that a workflow specification can be made at a higher level of abstraction. Within this framework it is possible to model sequential and concurrent activities with synchronization when necessary. It is also possible to model agent assignment and concurrent workflow instances. A logic programming approach to the computational problem is adopted.
2. Mesru Koprulu Spatio-temporal querying in video databases, 2001
In this thesis a video data model that allows efficient and effective representation and querying of spatio-temporal properties of objects is presented. The data model is focused on the semantic content of video streams. Objects, events, activities performed by objects are main interests of the model. The model supports fuzzy spatial queries including querying spatial relationships between objects and querying the trajectories of objects. The model is flexible enough to define new spatial relationship types between objects without changing the basic data model. A prototype of the proposed model has been implemented. The prototype allows various spatio-temporal queries along with the fuzzy ones and it is prone to implement compound queries without major changes in the data model.
3. Esen Kacar Mining Fuzzy Spatial Association Rules, 2001
Discovering interesting, implicit knowledge and general relationships in geographic information databases is very important to understand and to use these spatial data. One of the methods for discovering this implicit knowledge is mining spatial association rules. A spatial association rule is a rule indicating certain association relationships among a set of spatial and possibly non-spatial predicates. In the mining process, data is organized in a hierarchical manner. However, in real-world applications it may not be possible to construct a crisp structure for this data, rather some fuzzy structures should be used. Fuzziness, i.e. partial belonging of an item to more than one sub-item in the hierarchy, could be applied to the data itself, and also to the hierarchy of spatial relations. This thesis shows that, strong association rules can be mined from large spatial databases using fuzzy concept and spatial relation hierarchies.
4. Narin Emeksiz Diagnosis of Gastric Carcinoma Tumours by Multi Class Voting, 2001
5. Deniz Canturk Time-based workflow mining, 2005
Creating a workflow design is a complicated process and usually there are differences between the actual workflow processes and the processes as seen by the designer. Therefore, new data mining techniques for (re)discovering workflow models have been proposed. Starting point for such techniques are so-called “workflow logs" which contains information about the workflow process as it is actually being executed. In this paper, a new workflow mining technique based on time information is proposed. It is assumed that events in workflow logs are recorded with their start and end timestamps. This information is used in order to determine task orders and control flows between tasks. This new algorithm can be used to mine workflow graphs which contain basic workflow structures, such as sequential, parallel, iterative routings and or-join. The proposed algorithm finds a concrete workflow model as an output. In this workflow model execution durations of tasks and waiting times between tasks are included; hence the start time of each task and total execution time of the workflow can be discovered. This information could also be used in commenting on hidden tasks.
6. Guzen Erozel Natural Language Interface on a video data model, 2005
The video databases and retrieval of data from these databases have become popular in various business areas of work with the improvements in technology. As a kind of video database, video archive systems need user-friendly interfaces to retrieve video frames. In this thesis, an NLP based user interface to a video database system is developed using a content-based spatio-temporal video data model. The data model is focused on the semantic content which includes objects, activities, and spatial properties of objects. Spatio-temporal relationships between video objects and also trajectories of moving objects can be queried with this data model. In this video database system, NL interface enables flexible querying. The queries, which are given as English sentences, are parsed using Link Parser. Not only exact matches but similar objects and activities are also returned from the database with the help of the conceptual ontology module to return all related frames to the user. This module is implemented using a distance-based method of semantic similarity search on the semantic domain-independent ontology, WordNet. The semantic representations of the given queries are extracted from their syntactic structures using information extraction techniques. The extracted semantic representations are used to call the related parts of the underlying spatio-temporal video data model to calculate the results of the queries.
7. Onur Aydin Automated web service composition with event calculus, 2005
As the Web Services proliferate and complicate it is becoming an overwhelming job to manually prepare the Web Service Compositions which describe the communication and integration between Web Services. This thesis analyzes the usage of Event Calculus, which is one of the logical action-effect definition languages, for the automated preparation and execution of Web Service Compositions. In this context, planning capabilities of Event Calculus are utilized. Translations from Planning Domain Description Language and DARPA Agent Markup Language to Event Calculus are provided to show that Web Services can be composed with the help of Event Calculus. Also comparisons between Event Calculus and other planning languages used for the same purposes are presented.
8. Cigdem Celik An MPEG-7 Video Database System for content-basedf management and retrieval, 2005
A video data model that allows efficient and effective representation and querying of spatio-temporal properties of objects has been previously developed. The data model is focused on the semantic content of video streams. Objects, events, activities performed by objects are the main interests of the model. The model supports fuzzy spatial queries including querying spatial relationships between objects and querying the trajectories of objects. In this thesis, this work is used as a basis for the development of an XML-based video database system. This system is aimed to be compliant with the MPEG-7 Multimedia Description Schemes in order to obey a universal standard. The system is implemented using a native XML database management system. Query entrance facilities are enhanced via integrating an NLP interface.
9. Funda Karagoz Application of Schema Matching Methods to Semantic Web Service Discovery, 2006
The Web turns out to be a collection of services that interoperate through the Internet. As the number of services increase, it is getting more and more diffucult for users to find, filter and integrate these services depending on their requirements. Automatic techniques are being developed to fulfill these tasks. The first step toward automatic composition is the discovery of services needed. UDDI which is one of the accepted web standards, provides a registry of web services. However representation capabilities of UDDI are insufficient to search for services on the basis of what they provide. Semantic web initiatives like OWL and OWL-S are promising for locating exact services based on their capabilities. In this thesis, a new semantic service discovery mechanism is implemented based on OWL-S service profiles. The service profiles of an advertisement and a request are matched based on OWL ontologies describing them. In contrast to previous work on the subject, the ontologies of the advertisement and the request are not assumed to be same. In case they are different, schema matching algorithms are applied. Schema matching algorithms find the mappings between the given schema models. A hybrid combination of semantic, syntactic and structural schema matching algorithms are applied to match ontologies.
10. Huseyin Yilmaz Realizing the specification and execution of workflows through event calculus, 2006
Workflow management promises a solution to an age-old problem: controlling, monitoring, optimizing and supporting business processes. What is new about workflow management is the explicit representation of the business process logic which allows for computerized support. In the light of this support, many researchers developed different approaches to model new systems with different capabilities to solve this age-old problem. One of the approaches is using logic-based methodology for the specification and execution of workflows. Here, the event calculus, a logic programming formalism for representing events and their effects especially in database applications, is used for this approach. It is shown that the control flow graph of a workflow specification can be expressed as a set of logical formulas and the event calculus can be used to specify the role of a workflow manager through a set of rules for the execution dependencies of activities. Constructed workflow formalization through Event Calculus is realized by using recent technologies, and the resulting product is named as EventFlow, including some administrative interfaces to manage system and workflow engine. The architecture and implementation details of EventFlow, an editor developed for graphical representation of control flow graph, and used technologies are described. And an example application is built to show the usability and execution of the implemented system.
11. Esra Kırcı Automatic Composition of Semantic Web Services with the Abductive Event Calculus, 2007
This thesis investigates the application of AI planning techniques to the web service composition problem and in particular, it proposes the use of the abductive event calculus in this domain. Web service compositions are defined as templates using OWL-S ("OWL for Services"). These generic composition definitions are converted to Prolog language as axioms for the abductive event calculus planner and solutions found by the planner constitute the specific result plans for the generic composition plan. In this thesis it is shown that abductive planning capabilities of the event calculus can be used to generate the web service composition plans that realize the generic procedure.
12. Esat Kaan Kuban Abductive Planning Approach for Automated Web Service Composition using only User Specified Inputs and Outputs, 2008
Automated web service composition can be achieved either by generating the composition plan dynamically using given inputs and outputs, or by locating the correct services if an abstract process model
is given. This thesis investigates the former method which is dynamicly generating the composition by using the abductive planning capabilities of the Event Calculus. Event calculus axioms in Prolog language, are generated using the available OWL-S web service descriptions in the service repository, values given to selected inputs from ontologies used by those semantic web services and desired output types selected again from the ontologies. Abductive Theorem Prover which is the AI planner used in this thesis, generates composition plans and execution results according to the generated event calculus axioms.
13. Özkan Göktürk METADATA EXTRACTION FROM TEXT IN SOCCER DOMAIN, 2008
In this thesis, we present an approach of metadata extraction from match reports for soccer domain. The UEFA Cup and UEFA Champions League Match Reports are downloaded from the web site of UEFA by a web-crawler. These match reports are preprocessed by using regular expressions and then important events are extracted by using hand-written rules. In addition to hand-written rules, two different machine learning techniques are applied on match corpus to learn event patterns and automatically extract match events. Extracted events are saved in an MPEG-7 file. A user interface is implemented to query the events in the MPEG-7 match corpus and view the corresponding video segments.
14. Hilal Tarakçı AN ONTOLOGY-BASED MULTIMEDIA INFORMATION MANAGEMENT SYSTEM, 2008
In this thesis, MPEG-7 ontology is used on top and the given user-defined ontologies are attached to the MPEG-7 ontology via a user friendly interface, thus building MPEG-7 based ontologies automatically. Our proposed system is an ontology-based multimedia information management framework due to its modular architecture, ease of integrating with domain specific ontologies naturally and automatic harmonization of MPEG-7 ontology and domain-specific ontologies. Integration with domain specific ontologies is carried out by enabling import of domain ontologies via a user-friendly interface which makes the system independent of application domains.
15. Mehmet Kuzu AUTOMATIC WEB SERVICE COMPOSITION WITH AI PLANNING, 2009
In this thesis, some novel ideas are presented for solving automated web service composition problem. Some possible real world problems such as partial observability of environment, nondeterministic effects of web services, service execution failures are solved through some mechanisms. In addition to automated web service composition, automated web service invocation task is handled in this thesis by using reflection mechanism. The proposed approach is based on AI planning. Web service composition problem is translated to AI planning problem and a novel AI planner namely “Simplanner” that is designed for working in highly dynamic environments under time constraints is adapted to the proposed system. World altering service calls are done by conforming to the WS-Coordination and WS-Business Activity web service transaction specifications in order to physically repair failure situations and prevent undesired side effects of aborted web service composition efforts.
16. Onur Özorhan A Service Oriented Peer to Peer Web Service Discovery Mechanism With Categorization
This thesis, studies automated methods to achieve web service advertisement and discovery, and presents efficient search and matching techniques based on OWL-S. In the proposed system, the service discovery and matchmaking is performed via a centralized peer-to-peer web service repository. The repository has the ability to run on a software cloud, which improves the availability and scalability of the service discovery. The service advertisement is done semi-automatically on the client side, with an automatic WSDL to OWL-S conversion, and manual service description annotation. An OWL-S based unified ontology -Suggested Upper Merged Ontology is used during annotation, to enhance semantic matching abilities of the system. The service advertisement and availability are continuously monitored on the client side to improve the accuracy of the query results. User-agents generate query specification using the system ontology, to provide semantic unification between the client and the system during service discovery. Query matching is performed via complex Hilbert Spaces composed of conceptual planes and categorical similarities for each web service. User preferences following the service queries are monitored and used to improve the service match scores in the long run.