João Carlos Furtado

Constructive Genetic Algorithm for Clustering Problems

Genetic algorithms (GAs) have recently been accepted as powerful approaches to solving optimization problems. It is also well-accepted that building block construction (schemata formation and conservation) has a positive influence on GA behavior. Schemata are usually indirectly evaluated through a derived structure. We introduce a new approach called the Constructive Genetic Algorithm (CGA), which allows for schemata evaluation and the provision of other new features to the GA. Problems are modeled as bi-objective optimization problems that consider the evaluation of two fitness functions. This double fitness process, called fg-fitness, evaluates schemata and structures in a common basis. Evolution is conducted considering an adaptive rejection threshold that contemplates both objectives and attributes a rank to each individual in population. The population is dynamic in size and composed of schemata and structures. Recombination preserves good schemata, and mutation is applied to structures to get population diversification. The CGA is applied to two clustering problems in graphs. Representation of schemata and structures use a binary digit alphabet and are based on assignment (greedy) heuristics that provide a clearly distinguished representation for the problems. The clustering problems studied are the classical p-median and the capacitated p-median. Good results are shown for problem instances taken from the literature.

Propose of a Hardware Implementation for Fingerprint Systems

Fingerprint is graphical flow-like ridges presents on human fingers. Each fingerprint is unique, offering a clear and unambiguous method to identify an individual. The uniqueness of each fingerprint is determined by fine details embedded in its overall structure, named minutiae. Fingerprint classification system is CPU time intensive, usually implemented in software. This paper presents an alternative way to identify the minutiae from fingerprints, aiming real-time processing. In the first part is implemented the alternative algorithm in software (Delphi) and after this is presented an architecture to be implemented using a configurable devices (FPGA). The performance of this algorithm, in hardware and software, are analyzed, presenting the spent time within each system block.

CHEMOSTAT, UM SOFTWARE GRATUITO PARA ANÁLISE EXPLORATÓRIA DE DADOS MULTIVARIADOS

The objective of this work was to develop a free access exploratory data analysis software application for academic use that is easy to install and can be handled without user-level programming due to extensive use of chemometrics and its association with applications that require purchased licenses or routines. The developed software, called Chemostat, employs Hierarchical Cluster Analysis (HCA), Principal Component Analysis (PCA), intervals Principal Component Analysis (iPCA), as well as correction methods, data transformation and outlier detection. The data can be imported from the clipboard, text files, ASCII or FT-IR Perkin-Elmer “.sp” files. It generates a variety of charts and tables that allow the analysis of results that can be exported in several formats. The main features of the software were tested using midinfrared and near-infrared spectra in vegetable oils and digital images obtained from different types of commercial diesel. In order to validate the software results, the same sets of data were analyzed using Matlab© and the results in both applications matched in various combinations. In addition to the desktop version, the reuse of algorithms allowed an online version to be provided that offers a unique experience on the web. Both applications are available in English.

Análise exploratória aplicada no estudo de medicamentos contendo piroxicam

The identification of different pharmaceutical formulations with piroxicam was studied, using spectra of diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS), in association with hierarchical cluster analysis (HCA) technique. The spectra of samples of the 5 different compounding pharmacies, containing 10 or 20 mg of piroxicam and its respective inactive ingredients, had been collected in Nicolet Magna 550 spectrophotometer. For the multivariate analysis, the spectral information had been processed in software package Pirouette® 2.7 of the Infometrix. The dendograms had been constructed with the autoscaled data, and multiplicative scatter correction (MSC), using three types of linkage methods: single, flexible and incremental. By applying the hierarchical cluster analysis the formation of two distinct groups: one with the active principles and another group with the inactive ingredients was proved. These results demonstrate that the DRIFTS associated with chemometrics tools, constitute a quality control alternative of drugs production processes.

Determination of amoxicillin content in powdered pharmaceutical formulations using DRIFTS and PLS

The amount of amoxicillin in pharmaceutical formulations was determined using spectra of diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS), in association with partial least squares (PLS) regression. The spectra of 24 different samples (17 for the calibration set and 7 for the validation set), which had been registered using a Nicolet Magna 550 spectrophotometer, contained 76.7-94.3% of amoxicillin in starch. The PLS models were constructed with auto-scaled or variance-scaled data, and multiplicative scatter correction (MSC). The best model presented R2=0.9936, RMSEC=0.441 and RMSEV=0.790. The analytical method proposed is non-destructive and the cost and time of analysis are very much reduced, allowing for the fast and direct determination of amoxicillin content.

Otimização de métodos de controle de qualidade de fármacos usando algoritmo genético e busca tabu

Abstract Two new methodologies of analysis for the antihipertensive drugs quantification are provided in this work, using meta-heuristic algorithms optimization with infrared spectroscopy by diffuse reflectance Fourier transform (DRIFTS) and partial-least squares regression method (PLS). A diffuse reflectance joined to a spectrophotometry in the mid-infrared region was used. The calibration was through PLS in order to use it as a pre-processing. The data were used in multiplicative signal correction (MSC). After the best wavelength selection, which results in models with better coefficient regression (R 2 ), these were improved using routines based on genetic algorithm heuristic and tabu search methods. For the evaluation of the optimization a standard error of validation (SEV) was used. The new technique using DRIFTS/PLS/AG or DRIFTS/PLS/TS shows excellent choices for the quality control of the productive process of factories and drugstore. Keywords: genetic algorithm; tabu search; chemometrics; meta-heuristics.

Otimização de leiaute usando busca tabu

The search for high quality facility layouts can be viewed as combinatorial optimization problems arising in a wide variety of spatial planning contexts. We examine here the problem of optimizing a layout of facilities in a supplied space that can include unallowed areas. The layout space and facility areas are rectangular and limited by aspect rations. Considering the problem complexity, we propose a tabu search heuristic for the problem. First, an initial layout is generated using a clustering procedure. Considering n facilities, the representation is given by a binary tree with solution space size n!. The tabu search is then applied twofold, using the initial layout and using a random generated layout that maintains only the tree structure of the first layout. Quality results for both cases are obtained for problems of the literature.

The ten most common indicators in agreements involving profit sharing plans

Approving the Brazilian law for profit sharing plans (PSP) has brought a new perspective to the society when it comes to capital and labour relations. Concerning PSP, Law number 12.832 from June 2013 rules the relationship between business companies and workers, together with labour unions, providing to both parties the possibility of negotiating improvements on organisational processes for the companies and better pay for the employees. The main goal of this study is to present the results of a research developed with the ten most common indicators in 232 PSP agreements signed in Brazil between 2013 and 2014. The information used in this research was obtained in websites and at the headquarters of labour unions and companies from the issued region. The contracts were tabulated and analysed. From all information acquired, it was possible to extract 22 different performance indicators and, through the information acquired, it was concluded that the ten indicators pointed out here strongly represent the group studied, since they mean 84.99% of all indicators.

Método do enxame de partículas para otimização de modelos de regressão multivariada empregados na determinação de biodiesel em blendas biodiesel/óleo vegetal/diesel

Foram comparados diferentes modelos de regressao multivariada por minimos quadrados parciais para a quantificacao de biodiesel nas blendas binarias e ternarias biodiesel/oleo vegetal/diesel empregando espectrofotometria no infravermelho medio com reflexao total atenuada (FTIR/ATR). Um total de oitenta blendas binarias ou ternarias foram empregadas para a construcao e validacao dos modelos. O metodo do enxame de particulas (PSO) foi implementado para a otimizacao das regioes espectrais juntamente com a regressao por minimos quadrados parciais por intervalo (iPLS). Dentre os modelos por PLS empregando: toda a faixa espectral 4000-650 cm -1 , as regioes espectrais sugeridas pela norma ASTM NBR 15568 (1750-1735 cm -1 e 1200-1100 cm -1 ) e as regioes selecionadas pelo modelo hibrido iPLS-PSO, os melhores resultados de R 2 cal , RMSEC, RMSECV e RMSEP foram obtidos para o iPLS-PSO, que emprega uma abordagem deterministica (iPLS) combinada a uma abordagem heuristica (PSO). Assim e possivel utilizar a regressao por PLS para quantificacao dos teores de biodiesel em amostras reais de diesel comercial (blendas de biodiesel/diesel), mesmo quando estas foram intencionalmente adulteradas total ou parcialmente com oleo vegetal.

The performance measurement of innovation and competitiveness in the telecommunications services sector

From the growing trend of the services sector participation in the Brazilian economic scenario, the demand for studies on this subject seek to deepen the understanding about the behaviour of the aspects that influence the occurrence of such evolution. Following this sense, the present study aimed to propose a diagnostic model to measure the performance of innovation and competitiveness in the telecommunications service sector, providing resources to develop strategies, in order to turn the company capable of acting in a position according to direct and indirect main competitors, being development guided by five factors: service production, technology, human resources, finance and marketing. Once constructed the model, the implementation proved to be valid, presenting itself as a practical tool to support managers and consultants in the overall assessment of the company, allowing also to analyse its performance situation regarding to the development of competitive forms of positioning.