Adaptive Penalty and Barrier function based on Fuzzy Logic

Optimization methods have been used in many areas of knowledge, such as Engineering, Statistics, Chemistry, among others, to solve optimization problems. In many cases it is not possible to use derivative methods, due to the characteristics of the problem to be solved and/or its constraints, for example if the involved functions are non-smooth and/or their derivatives are not know. To solve this type of problems a Java based API has been implemented, which includes only derivative-free optimization methods, and that can be used to solve both constrained and unconstrained problems. For solving constrained problems, the classic Penalty and Barrier functions were included in the API. In this paper a new approach to Penalty and Barrier functions, based on Fuzzy Logic, is proposed. Two penalty functions, that impose a progressive penalization to solutions that violate the constraints, are discussed. The implemented functions impose a low penalization when the violation of the constraints is low and a heavy penalty when the violation is high. Numerical results, obtained using twenty-eight test problems, comparing the proposed Fuzzy Logic based functions to six of the classic Penalty and Barrier functions are presented. Considering the achieved results, it can be concluded that the proposed penalty functions besides being very robust also have a very good performance

Exploiting crowd sourced reviews to explain movie recommendation

International audienceStreaming services such as Netflix, M-Go, and Hulu use advanced recommender systems to help their customers identify relevant content quickly and easily. These recommenders display the list of recommended movies organized in sublists labeled with the genre or some more specific labels. Unfortunately , existing methods to extract these labeled sublists require human annotators to manually label movies, which is time-consuming and biased by the views of annotators. In this paper, we design a method that relies on crowd sourced reviews to automatically identify groups of similar movies and label these groups. Our method takes the content of movie reviews available online as input for an algorithm based on Latent Dirichlet Allocation (LDA) that identifies groups of similar movies. We separate the set of similar movies that share the same combination of genre in sublists and personalize the movies to show in each sublist using matrix factorization. The results of a side-by-side comparison of our method against Technicolor's M-Go VoD service are encouraging

Subsystems for future access networks

Current evolution and tendencies of Telecom Networks in general and more specifically optical Metro and Access Networks and their convergence are reported. Based on this evolution, a set of research lines are foreseen regarding subsystems and devices as: high speed optical sources, modulators and receivers, for the next generation of Passive Optical Networks. The ICT project EURO-FOS is achieving European level cooperative research among academia and industry, enabling future telecommunication networks

Beyond element-wise interactions: identifying complex interactions in biological processes

Background: Biological processes typically involve the interactions of a number of elements (genes, cells) acting on each others. Such processes are often modelled as networks whose nodes are the elements in question and edges pairwise relations between them (transcription, inhibition). But more often than not, elements actually work cooperatively or competitively to achieve a task. Or an element can act on the interaction between two others, as in the case of an enzyme controlling a reaction rate. We call “complex” these types of interaction and propose ways to identify them from time-series observations. Methodology: We use Granger Causality, a measure of the interaction between two signals, to characterize the influence of an enzyme on a reaction rate. We extend its traditional formulation to the case of multi-dimensional signals in order to capture group interactions, and not only element interactions. Our method is extensively tested on simulated data and applied to three biological datasets: microarray data of the Saccharomyces cerevisiae yeast, local field potential recordings of two brain areas and a metabolic reaction. Conclusions: Our results demonstrate that complex Granger causality can reveal new types of relation between signals and is particularly suited to biological data. Our approach raises some fundamental issues of the systems biology approach since finding all complex causalities (interactions) is an NP hard problem

Modeling the influence of production and storage conditions on the blueberry quality

Blueberry is a widely consumed fruit with major economic value, appreciated due to its characteristic flavor as well as health benefits. The present work aimed to evaluate the effect of several production factors and storage conditions on some chemical and physical properties of blueberries. Some physical and chemical characteristics (moisture, acidity, sugars, color and texture) of blueberries from three cultivars, originating from five different locations and conventional or organic farming, were evaluated. The variation of the properties along time was also evaluated for storage at room temperature and refrigeration. Moreover, artificial neural network models were developed to estimate the physical-chemical characteristics of the blueberries, as influenced by the production and conservation factors considered. The results showed that all the characteristics considered varied according to cultivar, place of cultivation and production mode. The storage conditions also induced changes in the chemical components as well as in color and texture. The changes were dependent on type and duration of storage, cultivar and production mode. Weight analysis of the artificial neural network models highlighted the patterns and trends observed experimentally.info:eu-repo/semantics/publishedVersio

Modelling Through Artificial Neural Networks of the Phenolic Compounds and Antioxidant Activity of Blueberries

The present study aimed at investigating the influence of several production factors, conservation conditions, and extraction procedures on the phenolic compounds and antioxidant activity of blueberries from different cultivars. The experimental data was used to train artificial neural networks, using a feed-forward model, which gave information about the variables affecting the antioxidant activity and the concentration of phenolic compounds in blueberries. The ANN input variables were location, cultivar, the age of the bushes, the altitude of the farm, production mode, state, storage time, type of extract and order of extract, while the output variables were total phenolic compounds, tannins as well as ABTS and DPPH antioxidant activity. The ANN model was fairly good, with values of the correlation factor for the whole dataset varying from 0.948 to 0.979, while the values of mean squared error were ranging from 0.846 to 0.018, for DPPH antioxidant acidity and anthocyanins, respectively. The results obtained showed that the methanol extracts contained higher amounts of total phenols and anthocyanins as compared to acetone: water extracts, while presenting similar quantities of tannins in both extracts. The blueberries from organic farming were richer in phenolic compounds and possessed higher antioxidant activity than those from conventional agriculture. Even though the effect of storage was not established with high certainty, a trend was observed for an increase in the phenolic compounds and antioxidant activity along storage, either when under refrigeration or under freezing, for the storage periods evaluated.info:eu-repo/semantics/publishedVersio

Magnetic field strength and orientation effects on co-fe discontinuous multilayers close to percolation

International audienceMagnetization and magnetoresistance in function of the magnitude and orientation of applied magnetic field were studied in Co-Fe discontinuous multilayers close to their structural percolation. The high pulsed magnetic fields up to 33 T were used in the 120–310 K temperature range. Comparison between longitudinal and transverse with respect to the film plane field configurations was made in the low-field and high-field regimes in order to clarify the nature of the measured negative magnetoresistance. Coexistence of two distinct magnetic fractions, superparamagnetic SPM, consisting of small spherical Co-Fe granules and superferromagnetic SFM, by bigger Co-Fe clusters, was established in this system. These fractions were shown to have different relevance for the system magnetization and magnetotransport. While the magnetization is almost completely up to 97% defined by the SFM contribution and practically independent of temperature in this range, the magnetoresistance experiences a crossover from a regime dominated by Langevin correlations suppressed with temperature between neighbor SPM and SFM moments at low fields, to that dominated by spin scattering enhanced with temperature of charge carriers within SFM clusters at high fields. Also, the demagnetizing effects, sensitive to the field orientation, were found to essentially define the low-field behavior and characteristic crossover field

Prediction of the cloud point of polyethoxylated surfactants and their mixtures by the thermodynamic model of Flory-Huggins-Rupert

The cloud point curves of polyethoxylated surfactants are established experimentally. These experimental data are preliminary to the development of the cloud point extraction process, which appears as an interesting alternative to the usual solvent extraction unit operation. Starting from the thermodynamic model developed by Flory and Huggins for phase separation of polymer aqueous solutions, this paper aims at the prediction of cloud point curves. In this work, Rupert’s approach is extended to commercial nonionic surfactants, mixtures of homologous species, namely a few alkylphenol and alcohol ethoxylates. The limit of such an approach is clearly demonstrated, provided that a fitting parameter is finally required for a successful model application to pilot-plant manufactured surfactants, like C8ΦEn (n = 7.5, 10, 12), C9ΦEn (n = 8, 10, 12), C12E4, C12E6 and commercial Tergitol 15-S-7 (linear C12-C14 secondary alcohol with an average of 7 ethylene oxide units

Data on European kitchen layouts belonging to vulnerable consumers (elderly people and young families with children or pregnant women) and risk-takers (young single men)

The data presented here capture the structure of kitchen lay- outs belonging to consumers vulnerable to foodborne dis- eases and food risk-takers. Data were collected in the frame of the SafeConsume project by multidisciplinary research teams that visited consumers during preparing a meal and had the possibility to examine their cooking routines. Dis- tances between sink and stove, sink and refrigerator, stove and refrigerator, sink and working place (countertop or ta- ble), stove and working place were analyzed to correlate food safety practices applied during cooking with kitchen arrange- ments. The results arising from analyzing the ergonomics of kitchens versus potential cross-contamination events are presented in Mihalache et al., [1]. These data contribute to a better understanding of real kitchen layouts and can be used as a starting point for future research regarding food safety-oriented arrangements instead of ergonomics-focused designs, for food safety risk assessments, as study cases for explaining specific measures that can be established to im- prove food handling and hygiene practices in homes and for sociological research pointing consumers’ behavior during cooking.info:eu-repo/semantics/publishedVersio

Kitchen layouts and consumers’ food hygiene practices: Ergonomics versus safety

Our paper emphasizes the importance of the kitchen layout in facilitating consumers' food hygiene practices. A significant correlation was found between the sink placement (inside or outside the kitchen) and hygienic practices during food handling based on a survey performed on consumers from ten European countries, indicating that those who had the sink in the kitchen were more likely to perform proper hygiene practices than those who have not. The self-reported practices were supported by observed practices in 64 households from five European countries. The observational study combined with the examination of kitchen layouts revealed that the kitchen work triangle with its apexes represented by the kitchen sink, cooking stove and refrigerator, which is recommended for ergonomic reasons by architects and designers, did not necessarily support food hygiene practices in kitchens. Cross-contamination events were associated with the sink – countertop distances longer than 1 m. Based on this, a new kitchen triangle with its apexes represented by the kitchen sink, working place (usually countertop) and cooking stove, with the distance between the sink and the working place less than 1 m is proposed to be used as norm in kitchen designs for combining ergonomics with safety. This triangle is proposedly named the food safety triangle and is aimed to mitigate the risks of foodborne illnesses by creating an arrangement that facilitates hygiene practices. This study is the first to highlight the importance of implementing the concept of food safety in the kitchen design based on significant correlations between kitchen equipment placement and consumers’ food safety practices.info:eu-repo/semantics/publishedVersio