Computing and Informatics (E-Journal - Institute of Informatics, SAS, Bratislava)
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Expressive Speech Synthesis for Critical Situations
Get PDFPresence of appropriate acoustic cues of affective features in the synthesized speech can be a prerequisite for the proper evaluation of the semantic content by the message recipient. In the recent work the authors have focused on the research of expressive speech synthesis capable of generating naturally sounding synthetic speech at various levels of arousal. Automatic information and warning systems can be used to inform, warn, instruct and navigate people in dangerous, critical situations, and increase the effectiveness of crisis management and rescue operations. One of the activities in the frame of the EU SF project CRISIS was called "Extremely expressive (hyper-expressive) speech synthesis for urgent warning messages generation''. It was aimed at research and development of speech synthesizers with high naturalness and intelligibility capable of generating messages with various expressive loads. The synthesizers will be applicable to generate public alert and warning messages in case of fires, floods, state security threats, etc. Early warning in relation to the situations mentioned above can be made thanks to fire and flood spread forecasting; modeling thereof is covered by other activities of the CRISIS project. The most important part needed for the synthesizer building is the expressive speech database. An original method is proposed to create such a database. The current version of the expressive speech database is introduced and first experiments with expressive synthesizers developed with this database are presented and discussed
An Extension of Two Conjugate Direction Methods to Markov Chain Problems
Get PDFMotivated by the recent applications of the conjugate residual method to nonsymmetric linear systems by Sogabe, Sugihara and Zhang [An extension of the conjugate residual method to nonsymmetric linear systems. J. Comput. Appl. Math., Vol. 266, 2009, pp. 103--113], this paper describes two conjugate direction methods, BiCR and BiCG, and attempts to extend their applications to compute the stationary probability distribution for an irreducible Markov chain with the aim of finding an alternative basic solver. Numerical experiments show the feasibility of the BiCR and BiCG to some extent, with applications to several practical Markov chain problems
Towards a Time Series Approach for the Classification and Evaluation of Collaborative Activities
Get PDFThe analysis and evaluation of computer-supported collaborative activities is a complex and tedious task. However, it is necessary in order to support collaborative scenarios, to scaffold the collaborative knowledge building and to evaluate the learning outcome. Various automated techniques have been proposed to minimize the workload of human evaluators and speed up the process. In this study, we propose a memory based learning model for the analysis, classification and evaluation of collaborative activities that makes use of time series techniques along with logfile analysis. We argue that the classification of collaborative sessions, with respect to their time series attributes, may be related to their qualitative aspects. Based on this rationale, we explore the use of the model under various settings. The results of the model are compared to assessments made by expert evaluators using a rating scheme. Correlation and error analyses are further conducted
Exploring the Selection of the Optimal Web Service Composition through Ant Colony Optimization
Get PDFThis paper presents an ant-inspired method for selecting the optimal or a near optimal solution in semantic Web service composition. The proposed method adapts and enhances the Ant Colony Optimization meta-heuristic and considers as selection criteria the QoS attributes of the services involved in the composition as well as the semantic similarity between them. To improve the performance of the proposed selection method a 1-OPT heuristic is defined which expands the search space in a controlled way so as to avoid the stagnation on local optimal solutions. The ant-inspired selection method has been evaluated on a set of scenarios having different complexities and comparatively analyzed with a cuckoo-inspired and a bee-inspired selection method
Proof Simplification in the Framework of Coherent Logic
Get PDFThe problem of proof simplification draws a lot of attention to itself across various contexts. In this paper, we present one approach for simplifying proofs constructed in the framework of coherent logic. This approach is motivated by the need for filtering-out "clean'' and short proofs from proof-traces, which typically contain many irrelevant steps, and which are generated by automated theorem provers - in this case, theorem provers based on coherent logic. Such "clean'' proofs can then be used for producing readable proofs in natural-language form. The proof simplification procedure consists of three transformation steps. The first one is based on the elimination of inference steps which are irrelevant for the present proof, also allowing some irrelevant branchings to be eliminated, the second one consists of lifting-up steps through the branching steps, followed by elimination of repeated steps, while the third one serves to convert proof fragments into the reductio ad absurdum form, if possible. In contrast to general simplification procedures, our proof simplification procedure is specific for a fragment of first order logic and therefore simple and easy to implement, and allows simple generation of object level proofs. We proceed to prove that this procedure is correct and terminating, and also that it never increases the size of a proof. Finally, we implement the proof simplification procedure, and provide several example proofs
Semantic Social Network Analysis for the Enterprise
Get PDFBusiness processes are generally fixed and enforced strictly, as reflected by the static nature of underlying software systems and datasets. However, internal and external situations, organizational changes and various other factors trigger dynamism, which is reflected in the form of issues, complains, Q&A, opinions, reviews, etc, over a plethora of communication channels, such as email, chat, discussion forums, and internal social network. Careful and timely analysis and processing of such channels may lead to early detection of emerging trends, critical issues, opportunities, topics of interests, contributors, experts etc. Social network analytics have been successfully applied in general purpose, online social network platforms, like Facebook and Twitter. However, in order for such techniques to be useful in business context, it is mandatory to integrate them with underlying business systems, processes and practices. Such integration problem is increasingly recognized as Big Data problem. We argue that SemanticWeb technology applied with social network analytics can solve enterprise knowledge management, while achieving integration
Parallel Processing in Web-Based Interactive Echocardiography Simulators
Get PDFMedical simulation is a new method of education in medicine. It allows training medical students or practitioners without the need to involve patients and makes them familiar with various kinds of examinations, especially related to medical imaging. Simulators that visualize examinations or operations require large computing power to keep time constraints of output presentation. A common approach to this problem is to use graphics processing units (GPU), but the code is not portable. The method of parallelization of processing is more important in component environments, to allow calculating projections in real time. In this paper parallelization issues in the ultrasound view simulation based on provided computer tomography images are analyzed. The proposed domain decomposition for this problem leads to significant reduction in simulation time and allows obtaining an animated visualization for currently available personal computers with multicore processors. The use of a component environment makes the solution portable and makes it possible to implement a web-based application that is the basis for eTraining. The method for creating animation in real time for such solutions is also analyzed
Optimal Pedestrian Path Planning in Evacuation Scenario
Get PDFSimulation of evacuation plans is a relatively complex problem. It is necessary to simulate a number of separate processes which interact in the result. Namely, they are pedestrian-pedestrian interactions, pedestrian-static object (e.g. wall) interactions and pedestrian-environment (fire, smoke, etc.) interactions. In this case, the evacuation simulation is controled on the microscopic level. Microscopic level considers each individual separately and pedestrian is planning his/her path to the exit with regard to the above-mentioned interactions. In this article we focus on path planning during evacuation and describe algorithms applied in this area. At the end we propose a method of the space evaluation with linear time complexity and planned path compared with commercial software tools
Drawings in Computer-Supported Collaborative Learning - Empirical and Technical Results
Get PDFSelf-constructed external representations are thought to be beneficial in teaching and learning, especially when embedded in peer interactions, and can positively affect the course and type of reasoning, for example by providing grounding for explanations and self-explanations, by helping to disambiguate students' mental models of phenomena, or by increasing and sharing the task focus. This paper reports on the results of research efforts investigating which conditions are advantageous in collaborative drawing activities in computer-supported learning scenarios for young students. We describe the design, technical implementation and empirical results of a study with 94 primary school students working on a collaborative drawing task in various conditions that include adaptive prompting and scripted activities. Results showed, partially in line with our expectations, that adaptive prompting as well as scripting positively affected students' learning outcomes and discourse quality. Students in both supported conditions more often critically reviewed the work of their partner and integrated ideas from their partner in their own reasoning
Monitoring-Aware Learning Design Process: Pilot Studies in Authentic CSCL Scenarios
Get PDFICT tools offer the possibility to store, analyse and visualise large amounts of educational data. However, in order to make sense of these analyses, teachers need meaningful information connected to their pedagogical intentions. We envision an enriched learning-design process, which supports the integration of the issues related to monitoring in the script. This paper presents a study where the first author and a teacher iteratively co-designed two authentic learning scenarios with the aim of defining and evaluating a monitoring-aware design model and process. These two proposals, the model and the process, were positively evaluated by the participant teacher, and are the basis for the future implementation of an authoring tool that will support the proposed monitoring-aware design process