2012
Authors
Ribeiro, AR; Martinho, I; Tillak, JB; Bernacka Wojcik, I; Barata, D; Jorge, PAS; Aguas, H; Oliva, AG;
Publication
22ND INTERNATIONAL CONFERENCE ON OPTICAL FIBER SENSORS, PTS 1-3
Abstract
In this paper an optofluidic chip for simultaneous determination of refractive index and acquisition of absorption or fluorescent spectra is described. The system comprises a microfluidic channel with multiple inlet/outlet for sample handling and a dual fiber optic probe, standing face to face across the channel, for the optical measurements. An FBG based Fabry Perot cavity, and a Braggmeter, allow for interferometric measurement of the refractive index while external illumination and a multimode fiber enable acquisition of the absorption/fluorescence spectra with a CCD spectrometer. Preliminary results showing the viability of simultaneous measurement are obtained from the characterization of mixed samples with distinct refractive index and dye concentrations.
2012
Authors
Ventura, J; Sousa, R; Ferreira, A;
Publication
5th International Symposium on Communications Control and Signal Processing, ISCCSP 2012
Abstract
Vibrato is a frequency modulation effect of the singing voice and is very relevant in musical terms. Its most important characteristics are the vibrato frequency (in Hertz) and the vibrato extension (in semitones). In singing teaching and learning, it is very convenient to provide a visual feedback of those two objective signal characteristics, in real-time. In this paper we describe an algorithm performing vibrato detection and analysis. Since this capability depends on fundamental frequency (F0) analysis of the singing voice, we first discuss F0 estimation and compare three algorithms that are used in voice and speech analysis. Then we describe the vibrato detection and analysis algorithm and assess its performance using both synthetic and natural singing signals. Overall, results indicate that the relative estimation errors in vibrato frequency and extension are lower than 0.1%. © 2012 IEEE.
2012
Authors
Gazis, A; Fontes, T; Bandeira, J; Pereira, S; Coelho, MC;
Publication
IWCTS 2012 - 5th ACM SIGSPATIAL International Workshop on Computational Transportation Science
Abstract
This paper focuses on the integration of multiple computational tools towards the objective of assessing emission impacts of different routes. Data from real life GPS tracks was integrated with traffic emission modelling for multiple pollutants (NOx, HC, CO and PM10) to investigate different routing strategies. The main conclusion is that different pollutants dictate different best routes. Hence, strategies for assigning relative weights to pollutants are devised in order to be able to select the best environment-friendly route. © 2012 ACM.
2012
Authors
Malheiro, B; Crabeel, N; Campos Neves, B;
Publication
International Journal of Online Engineering (iJOE) - Int. J. Onl. Eng.
Abstract
2012
Authors
Guimaraes, L; Klabjan, D; Almada Lobo, B;
Publication
ENGINEERING APPLICATIONS OF ARTIFICIAL INTELLIGENCE
Abstract
Driven by a real-world application in the beverage industry, this paper provides a design of a new VNS variant to tackle the annual production budget problem. The problem consists of assigning and scheduling production lots in a multi-plant environment, where each plant has a set of filling lines that bottle and pack drinks. Plans also consider final product transfers between the plants. Our algorithm fixes setup variables for family of products and determines production, inventory and transfer decisions by solving a linear programming (LP) model. As we are dealing with very large problem instances, it is inefficient and unpractical to search the entire neighborhood of the incumbent solution at each iteration of the algorithm. We explore the sensitivity analysis of the LP to guide the partial neighborhood search. Dual-reoptimization is also used to speed-up the solution procedure. Tests with instances from our case study have shown that the algorithm can substantially improve the current business practice, and it is more competitive than state-of-the-art commercial solvers and other VNS variants.
2012
Authors
Dovier, A; Costa, VS;
Publication
THEORY AND PRACTICE OF LOGIC PROGRAMMING
Abstract
The access to the final selection minute is only available to applicants.
Please check the confirmation e-mail of your application to obtain the access code.