Turku Centre for Computer Science

About: Turku Centre for Computer Science is a facility organization based out in Turku, Finland. It is known for research contribution in the topics: Decidability & Word (group theory). The organization has 382 authors who have published 1027 publications receiving 19560 citations.

Parikh Matrices: Subword Indicators and Degrees of Ambiguity.

Abstract: The quantity \(|w|_{u}\), the number of occurrences of a word u as a (scattered) subword of a word w gives important numerical information about the word w. Properly chosen values \(|w|_{u}\), for different u’s, characterize the word w completely. Certain upper triangular matrices, customarily referred to as Parikh matrices have turned out to be very useful for computing numbers \(|w|_{u}\). This partially expository paper discusses some highlights and open problems of the theory of Parikh matrices and subword occurrences. Special emphasis is on subword indicators and degrees of ambiguity.

Exploring Interface Sign Ontologies for Web User Interface Design and Evaluation: A User Study

Abstract: The aim of this paper is twofold: firstly, to find the set of ontologies (i.e., the set of concepts and skills) presupposed by users when interpreting the meaning of web interface signs (i.e., the smallest elements of web user interfaces), and secondly, to investigate users’ difficulties in interpreting the meanings of interface signs belonging to different kinds of ontologies. In order to achieve these aims an empirical user study was conducted with 26 test participants. The study data was gathered by semi-structured interviews and questionnaires. Following an empirical research approach, descriptive statistics and qualitative data analysis were used to analyze the data. The study results provide a total of twelve ontologies and reveal the users’ difficulties in interpreting the meanings of interface signs belonging to different kinds of ontologies.

Comparison of mesh and honeycomb network-on-chip architectures

Abstract: Rectangular Mesh is the most commonly used topology in the field of Network-on-Chip (NoC) due to its high regularity, symmetry and scalability. In this paper, we examine Honeycomb topology as another candidate for NoC architectures. Based on the simulations of Mesh and Honeycomb routers and network, we compare these two topologies in terms of power consumption, area cost and communication delay. Results show that Honeycomb topology outperforms Mesh by at least 25.9%, 54.2% and 30.0% in these three aspects.

An analog current-mode 2-D DCT implementation

Abstract: In this paper the rst measurements results of an analog current-mode 2-D DCT test chip are presented. The circuit performs 4-point transform and the measured results con rm the correct operation of the circuit. Moreover, the accuracy of the results is on acceptable level and ful I the imposed requirements in this respect.