Varieties of Cost Functions

Regular cost functions were introduced as a quantitative generalisation of regular languages, retaining many of their equivalent characterisations and decidability properties. For instance, stabilisation monoids play the same role for cost functions as monoids do for regular languages. The purpose of this article is to further extend this algebraic approach by generalising two results on regular languages to cost functions: Eilenberg\u27s varieties theorem and profinite equational characterisations of lattices of regular languages. This opens interesting new perspectives, but the specificities of cost functions introduce difficulties that prevent these generalisations to be straightforward. In contrast, although syntactic algebras can be defined for formal power series over a commutative ring, no such notion is known for series over semirings and in particular over the tropical semiring

Bringing Understanding of Simulation Material to Interaction Designers

Simulation-based tools are complex and obscure software. However, a company may benefit from using such tools, as they provide more precise and accurate information. Ericsson has developed a RAN simulator that allows to model cellular networks taking into account even their smallest aspects. This allows to compare different solutions for particular case and select the best one. Therefore, Ericsson can propose better, i. e. most efficient and less cost, solutions to its customers. However, the RAN simulator is developed in MATLAB and does not have any graphical user interface. Therefore, it is not possible for people who manage sales at Ericsson to use it, because they have no skills for it. This, in fact, raises the need of development of a tool that will provide sales people with a convenient way to access the RAN simulator. This research describes a process of prototyping three simulation-based tools for Ericsson. It covers a process of providing interaction designers with the knowledge about simulations. The research gives insights on important details of the simulations that are needed to be delivered to the designers, as well as aspects of developing simulation-based tools within multidisciplinary team. Moreover, the research introduces a “mediator person” who can significantly help and improve the process of the development of simulation-based tools

A 2D wave finite element-based superelement formulation for acoustic analysis of cavities of arbitrary shapes

International audienceA substructuring technique is proposed which enables fast computation of the acoustic response of arbitrary-shaped 2D cavities subject to different kinds of excitations. It combines rectangular superelements which are modeled by means of the wave finite element (WFE) method, and arbitrary-shaped superelements modeled using component mode synthesis (CMS). Within the WFE framework, the so-called receptance matrices of rectangular superelements — which link the pressure vectors to the acoustic force vectors over the boundaries — can be derived in an efficient way in terms of wave modes, without the need of explicitly condensing the internal degrees of freedom of the systems. A model reduction strategy is proposed which aims at expressing the receptance matrices with a few wave modes only. The proposed strategy involves enclosing each rectangular superelement in a finite element (FE) layer with a small width. In this way, smoothed pressure fields are likely to occur over the WFE superelements, hence enabling these superelements to be described with a few wave modes only. By considering those WFE-based rectangular superelements surrounded by FE layers, this yields the so-called hybrid WFE/FE superelements whose dynamic stiffness matrices can be computed in a very fast way. Modeling a whole arbitrary-shaped acoustic cavity follows from conventional assembly procedure between hybrid WFE/FE superelements, CMS superelements and other FE components. Numerical experiments are carried out to highlight the relevance of the proposed substructuring technique

Improved algorithm for heart rate measurement using mobile phone camera

Nowadays a lot of different ways to measure person's heart rate are exist. One of such ways is using mobile phone. It is very easy for the person and do not require any special skills or buying special devices. All that is needed for heart rate measurement is mobile phone with on-board camera with flash equipped. In this paper we overview existing algorithms for heart rate measuring using mobile phone and propose improved algorithm, that is more efficient, than reviewed ones

RoDaFlow: A framework for development of dataflow network agents in Smart-M3 with substitution method

The paper describes RoDaFlow - a framework for development of dataflow network agents on Smart-M3 platform. The agents created with the use of the framework support the substitution mechanism that allows to keep the dataflow network based systems in working conditions when some of its agents fall out. The RoDaFlow framework is implemented in Java with the use of Smart-M3 Java KPI library. It allows to develop primary and substitute agents by implementing only their programs, which define how agents process incoming information. The paper also describes a prototype of home light control system based on the dataflow network that allows to effectively control the light in a home. This system uses a number of sensors, actuators, remote control units and computational agents. The agents use information from remote control units and sensors to control the actuators and thus the light level in the home rooms. The agents for the prototype were developed with the use of proposed framework