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.

High-performance programs by source-level merging of RVC-CAL dataflow actors

Abstract: RVC-CAL is a dataflow language that has acquired an ecosystem of sophisticated design tools. Previous works have shown that RVC-CAL-based applications can automatically be deployed to multiprocessor platforms, as well as hardware descriptions with high efficiency. However, as RVC-CAL is a concurrent language, code generation for a single processor core requires careful application analysis and scheduling. Although much work has been done in this area, to this date no publication has reported that programs generated from RVC-CAL could rival handwritten programs on single-core processors. This paper proposes performance optimization of RVC-CAL applications by actor merging at source code level. The proposed methodology is demonstrated with an IEEE 802.15.4 (ZigBee) transmitter case study. The transmitter baseband software, previously written in C, is rewritten in RVC-CAL and optimized with the proposed methodology. Experiments show that on a VLIW-flavored processor the RVC-CAL-based program achieves the performance of manually written software.

The Structure of Infinite Solutions of Marked and Binary Post Correspondence Problems

Abstract: In the infinite Post Correspondence Problem an instance (h,g) consists of two morphisms h and g, and the problem is to determine whether or not there exists an infinite word ω such that h(ω) = g(ω). This problem is undecidable in general, but it is known to be decidable for binary and marked instances. A morphism is binary if the domain alphabet is of size 2, and marked if each image of a letter begins with a different letter. We prove that the solutions of a marked instance form a set Eω ⋃ E* (P ⋃ F), where P is a finite set of ultimately periodic words, E is a finite set of solutions of the PCP, and F is a finite set of morphic images of fixed points of D0L systems. We also establish the structure of infinite solutions of the binary PCP.

From Smart Meter Data to Pricing Intelligence -- Visual Data Mining towards Real-Time BI

Abstract: The deployment of smart metering in the electricity industry has opened up the opportunity for real-time BI-enabled innovative business applications, such as demand response. Taking a holistic view of BI, this study introduced a visual data mining driven application in order to exemplify the potentials of real-time BI to the electricity businesses. The empirical findings indicate that such an application is capable of extracting actionable insights about customer’s electricity consumption patterns, which will lead to turn timely measured data into pricing intelligence. Based on the findings, we proposed a real-time BI framework, and discussed how it will facilitate the formulation of strategic initiatives for transforming the electricity utility towards sustainable growth. Our research is conducted by following the design science research paradigm. By addressing an emerging issue in the problem domain, it adds empirical knowledge to the BI research landscape.