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This paper studies the problem of tangible assets acquisition within the company by proposing a new hybrid model that uses linear programming and fuzzy numbers. Regarding linear programming, two methods were implemented in the model, namely: the graphical method and the primal simplex algorithm. This hybrid model is proposed for solving investment decision problems, based on decision variables, objective function coefficients, and a matrix of constraints, all of them presented in the form of triangular fuzzy numbers. Solving the primal simplex algorithm using fuzzy numbers and coefficients, allowed the results of the linear programming problem to also be in the form of fuzzy variables. The fuzzy variables compared to the crisp variables allow the determination of optimal intervals for which the objective function has values depending on the fuzzy variables. The major advantage of this model is that the results are presented as value ranges that intervene in the decision-making process. Thus, the company&rsquo, s decision makers can select any of the result values as they satisfy two basic requirements namely: minimizing/maximizing the objective function and satisfying the basic requirements regarding the constraints resulting from the company&rsquo, s activity. The paper is accompanied by a practical example.

International audience; In situ electrochemical impedance spectroscopy (EIS) and ex situ X-ray photoelectron spectroscopy (XPS) measurements on electrogenerated zirconium oxide films on zirconium (Zr/ZrO2) were used to quantify the oxide film thickness and resistivity profiles through the oxide. The EIS analysis presented here takes advantage of the high-frequency domain at which the constant-phase element (CPE) behavior of the oxide film reverts to a capacitive response and the Cole-Cole representations of the complex capacitance to extract the high-frequency capacitance of the oxide film without reference to the nature of the timeconstantdistribution within the oxide film. The film thickness of the ZrO2 samples measured from the high-frequency capacitance of EIS were in good agreement with the thickness obtained from XPS. Moreover, the EIS analysis presented is based on the use of the integral solution of the power law model, which allows to obtain in one single EIS experiment, both the film thickness and the resistivity profile in the ZrO2 film. This work suggests a convenient graphical method to extract film properties and serves tovalidate a key assumption of the power-law model for interpretation of CPE parameters in terms of physical properties.

RESUMO A biomassa polidispersa tem como uma de suas principais características as variações das dimensões e dos formatos de suas partículas. Os métodos de determinação do diâmetro médio por peneiramento, amplamente utilizados devido a sua relativa simplicidade e baixo custo, quando aplicados a materiais heterogêneos, como a biomassa polidispersa, podem levar a resultados equivocados. Assim, com o objetivo de obter resultados mais precisos, foram avaliados três métodos de determinação do diâmetro médio de partículas de biomassa polidispersa, baseados na técnica de fracionamento por peneiramento mecânico: um de forma analítica (Diâmetro de Sauter) e outros dois por meio de análise gráfica das funções de distribuição das partículas (Função de Densidade de Distribuição Mássica e Função Cumulativa/Aumentativa de Distribuição). O método baseado na análise gráfica da função da distribuição da densidade mássica (FDDM) foi o mais eficiente para a análise do bagaço de cana, pois permitiu identificar as diferentes populações existentes e identificar com clareza as dimensões características, mostrando assim ser uma poderosa ferramenta para a análise granulométrica de biomassas polidispersas. ABSTRACT Polydispersed biomass has as one of the main features variations in particle dimension and size. Mean diameter determination methods by screening are widely used due to their relative simplicity and low cost. However, when applied for heterogeneous materials such as polydispersed biomass, they can lead to misleading results. Thus, we evaluated three methods for determining mean diameter of polydispersed biomass particles, aiming at most accurate results. The methods are based on size fractionation by mechanical sieving: one analytical (Sauter diameter) and two by graphical analysis of particle distribution functions (Mass Distribution Density - MDD and Cumulative/ Augmentative Distribution - CAD). The method based on graphical analysis of mass distribution density (MDD) was the most efficient for sugarcane bagasse analysis, once it enabled detecting different populations and clearly identifying their respective characteristic dimensions. Therefore, it is a powerful tool for particle size analysis of polydispersed biomass.

Accepted: 2016-04-07, 資料番号: SA1160176000

The authors gratefully thank the sponsorship of Fundação para a Ciência e Tecnologia through the Strategic Project UID/EMS/00667/2013 – UNIDEMI. Axiomatic Design classifies designs into three basic types: uncoupled, decoupled and coupled. The first type encompasses the ideal designs, where independence is always ensured, the second includes the designs where independence can be achieved using the right sequence to fine-tune the design parameters as to satisfy the given set of functional requirements, while the last comprises designs for which independence can never be achieved. Usually, coupled designs are avoided and designers are encouraged to redesign their solutions until an uncoupled or a decoupled one is achieved. Nevertheless, coupled solutions are often hard to avoid. This paper discusses this issue and uses a simple graphical example on how to adjust either the functional requirements or the design parameters of a 2-FR, 2-DP coupled design that is regarded as being uncoupled, as to attain the minimum information content. publishersversion published

International audience; This paper investigates the implementation of an analytical model to determine the porosity of a granular material during reactive and nonreactive sintering. A graphical interpretation of this model is proposed to calculate the porosity by comparing the experimental shrinkage curve with the ideal one. For the nonreactive sintering, some examples have been taken from the literature to illustrate the application of this method for two granular materials (alumina and zircon). In the case of reactive sintering, we have used our experiments to study the sintering behavior of magnesium hydroxide. The shrinkage curve was determined by dilatometer and the porosity was measured by helium pycnometer. The comparison revealed that the porosity calculated from the model is fully consistent with the porosity measurements in the both cases.

The most widely used statistical method that is usedto determine the wind energy potential for a specific region is Weibulldistribution or probability function. Using two-parameter Weibull distributionfunction, wind characteristics such as mean wind speed and mean wind power canbe forecasted. In this study, the mean wind speed and wind power potential forAntalya are determined using Graphical, Moment and Maximum Likelihood methodswith the help of the data taken from Antalya-Elmalı Meteorological Station. Inthis way, predicting the wind energy potential of Antalya region, it isdiscussed whether the possible installation of a wind power plant is feasibleor not in this area. The results obtained are evaluated by using error analysismethods that are the Coefficient of Determination (R2) and Root MeanSquares Error (RMSE)., Belirli bir bölgenin rüzgâr enerjisi potansiyelinibelirlemede en yaygın kullanılan istatistiksel yöntem Weibull dağılımfonksiyonudur. İki parametreli Weibull dağılım fonksiyonu ile ortalama rüzgârhızı, ve ortalama rüzgâr gücü gibi rüzgar karakteristikleri tahminedilebilmektedir. Bu çalışmada, Antalya ili için ortalama rüzgâr hızı ve rüzgârgücü potansiyeli grafik, moment ve maksimum olabilirlik yöntemleri kullanılarakAntalya-Elmalı Bölge Meteoroloji İstasyonu'ndan alınan veriler yardımıylabelirlenmiştir. Böylece Antalya Bölgesinin rüzgâr enerji potansiyeli tahminedilerek olası bir rüzgâr enerjisi santrali kurulumunun uygun olup olmayacağıtartışılmıştır. Elde edilen sonuçlar için ortalama hata kareleri toplamı kökü (RMSE) ve belirlilik katsayısı (R2) hataanalizleri yapılmıştır.

One of the applied methods for environmental impact assessment is the index of global pollution (IGP) proposed by Rojanschi in 1991. This methodology enables the global estimation for the ecosystem state affected more or less by human activities. Unfortunately, Rojanschi’s method has a limitation; it can be applied only if at least three environmental components are considered. Frequently, many environmental impact assessment applications rely on analysis of only two environmental components. Therefore, this work aimed to develop a new graphical method to extend Rojanschi’s approach for the case of two environmental components. The proposed method avoids the average value of evaluation grades and uses only the graphical correspondence for calculation of the index of global pollution. A right-angle triangle graph methodology was proposed, where bases represented the values of evaluation grades. Thus, for the case of two environmental components, the index of global pollution was calculated as the relation between the ideal and real ecosystem states represented by the ratio between areas of external and enclosed right triangles. The developed graphical method was tested and validated for real case studies: the environmental impact assessment from a refinery located on the Romanian Black Sea Coast considering Air and Water environmental components and from a coal-fired thermoelectric power plant from Eastern Romania regarding Air and Soil environmental components. In this way, it was provided a reliable and faster tool to be used for the pollution characterization of human-derived chemicals for better decisions in risk management.