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Marketing researches reveal that displayed inventory and allocated shelf space affect the demand of some retail items. We study periodic inventory policy when demand is uncertain and its probability distribution function depends on inventory level and period length. Profit function including sale revenue, holding, shortage, and ordering costs is presented. To capture real world situation we propose natural properties for demand probability distribution. Considering those properties well fitted demand distributions are presented. Finally optimal policy is explored via numerical examples. Numerical study reveals that optimal value of decision variables is not monotonic with respect to demand sensitivity to the inventory. [ABSTRACT FROM AUTHOR]

Utopia, utopia or utopia are among the concepts that have occupied the minds of thinkers for many years. Utopian thought is that part of thought throughout history that examines the way to achieve a way of life that is associated with well-being and success. In front of Dystopia, there is a dystopia where people will not achieve victory and salvation, societies have moral vices and arrogance that prevent the citizens of such societies from achieving salvation. In this research, the author intends to study and read Hafez Shirazi's sonnets and compare it with Lucien Goldman's sociological components and analysis of poems, to look at a comprehensive view of utopia and destruction in Hafez's sonnets. The present research method is descriptive-analytical. The data required for analysis has been collected through library-reference studies. [ABSTRACT FROM AUTHOR]

Purpose: One of the recent applications of fabrics is to use them for sound insulation. Accordingly, due to their low production cost and low relative density, fabrics have drawn attention in some of the industries such as the automotive and aircraft industries. The present study is aimed to investigate the effects of the fiber cross-section, porosity, thickness of samples and fuzzing of the knitted fabric on the sound absorption coefficient. Design/methodology/approach: In the present study, fabrics with three different stitch densities were knitted by yarns consist of three different forms of fiber cross-section shapes (circular, elliptical and plus-shaped). In this work, the sound absorption coefficient of knitted fabrics was investigated with regard to the different fiber cross-sections and structural parameters using an impedance tube. Findings: As indicated by the obtained results, the cross-section, porosity, thickness and mass per unit area of the fabrics were the determinant factors for the sound absorption coefficient. In addition to, the sound absorption coefficient and porosity were shown to have an inverse relationship. Originality/value: A section of the present paper has been allocated to the investigation of the effect of the fiber cross-section and fuzzing of fabric on the sound absorption of plain knitted fabrics. [ABSTRACT FROM AUTHOR]

The paper authored by Amit et al. [Amit, R. K., Mehta, P., & Tripathi, R. R. "Optimal shelf-space stocking policy using stochastic dominance under supply-driven demand uncertainty", European Journal of Operational Research, 246(1), pp. 339-342 (2015)] proposes a newsvendor model in which demand depends on displayed inventory. Under stochastic dominance conditions, they claimed that the profit function is concave at its extremum points. In the present study, it is expressed that this statement is not generally precise. [ABSTRACT FROM AUTHOR]

Background: One of the fields of research in recent years that has been under focused is emotion recognition in electroencephalography (EEG) signals. This study provides a four-layer method to improve people's emotion recognition through these signals and deep belief neural networks. Methods: In this study, using DEAP dataset, a four-layer method is established, which includes (1) preprocessing, (2) extracting features, (3) dimension reduction, and (4) emotion identification and estimation. To find the optimal choice in some of the steps of these layers, three different tests have been conducted. The first is finding the perfect window in feature extraction section that resulted in superiority of Hamming window to the other windows. The second is choosing the most appropriate number of filter bank and the best result was 26. The third test was also emotion recognition that its accuracy was 92.93 for arousal dimension, 92.64 for valence dimension, 93.14 for dominance dimension in two-class experiment and 76.28 for the arousal, 74.83 for the valence, and 75.64 for dominance in three-class experiment. Results: The results of this method show an improvement of 12.34% and 7.74% in two- and three-class levels in the arousal dimension. This improvement in the valence is 12.77 and 8.52, respectively. Conclusion: The results show that the proposed method can be used to improve the accuracy of emotion recognition. [ABSTRACT FROM AUTHOR]

Purpose The purpose of this paper is to: investigate coating of polylactic acid by TiO2 using low-temperature plasma technique, which is a clean and environmentally benign process; study the characteristics of the obtained samples; and survey the antibacterial effect of nano-TiO2. This method, as an eco-friendly technology used on the biodegradable polymer, would be benefited by industries which want to set feet on the greener path and reduce the social costs resulting from the harmful effects of pollutants.Design/methodology/approach TiO2 was coated on a textile by DC magnetron sputtering. In this study titanium as a pure Ti anode is coated on the sample surface in the plasma reactor by entering argon gas (Ar). Then titanium oxide appears through entering oxygen (O2) into the reactor.Findings Scanning electron microscopy analysis is applied to show the morphology of the coated surface. The quantitative value of TiO2 was evaluated as weight percentage using X-ray fluorescence (XRF) and washing stability of the samples is measured using the XRF machine. The highest degree of antibacterial effects and washing stability are all observed in 10 min.Originality/value In this process, contrary to common methods, pure Ti is used for coating. Finishing of textiles via this method has been useful to be used as disposable hospital clothing due to its biodegradable and antibacterial properties. So it will be helpful in reducing negative environmental impacts. [ABSTRACT FROM AUTHOR]

The objectives of this work were to study the influence of sugar, starch and Hydroxypropylmethylcellulose (HPMC) concentrations on Porosity and textural properties of sponge cakes for optimization of formulation for low-sugar cake. Response surface methodology (RSM) was performed to examine the effects of independent variables on porosity and firmness and to determine the optimum level of ingredients . Independent variables selected for the study were: sugar concentration (0, 10 and 20 % w/w), HPMC concentration (0, 0.5 and 1 %w/w) and starch concentration (0, 5 and 10 %w/w). For each response, second order polynomial models were developed using multiple linear regression analysis. Analysis of variance was performed to check the adequacy and accuracy of the fitted models. The optimum values for sugar, HPMC and starch concentrations were found to be 10, 0.5, and 5 %, respectively. These levels of ingredients led to porosity and firmness values of 76.56 % and 13.00 N respectively. The microstructures of samples were also analyzed using scanning electron microscopy and it was found that SEM pictures confirmed the RSM results about the effects of ingredients on porosity. [ABSTRACT FROM AUTHOR]

We consider an M/M/1 queueing system with inventory under the $$(r,Q)$$ policy and with lost sales, in which demands occur according to a Poisson process and service times are exponentially distributed. All arriving customers during stockout are lost. We derive the stationary distributions of the joint queue length (number of customers in the system) and on-hand inventory when lead times are random variables and can take various distributions. The derived stationary distributions are used to formulate long-run average performance measures and cost functions in some numerical examples. [ABSTRACT FROM AUTHOR]

The effects of adding one of the species of Iranian gum tragacanth, Astragalus compactus, to maltodextrin solutions used for microencapsulation of 2-methylbutyl acetate (water-soluble flavoring compound of strawberry) were studied. Initial emulsions were evaluated regarding rheological behavior and particle size distribution. The resulted microcapsules were also analyzed for particle size distributions, glass transition temperature Tg, the morphology of the capsules and the rate of release from them. The results showed that addition of 0.5% w/w A. compactus gum to maltodextrin solutions (14.5% w/w) can increase the viscosity and Tg to an optimum level and can prevent stickiness. Also this species of gum tragacanth had an interesting effect in reducing physical defects of microcapsules and eliminated ruptures significantly. It was also showed that the rate of release of 2-methylbutyl acetate decreased by incorporating gum tragacanth in the wall material. Practical Applications Microencapsulation is of great interest in preservation of flavoring compounds. One of the most important wall materials is maltodextrin, which has several defects to protect flavorings. This study proposes the use of a new material, Iranian gum tragacanth from Astragalus compactus, to overcome these defects. It was found that new microcapsules did not undergo rupture and could retain the flavoring well. [ABSTRACT FROM AUTHOR]

Dispersions of different species of gum tragacanth were sonicated at a frequency of 24 kHz with a total nominal output power of 200 W for different time intervals (0, 7, 15, 45 and 90 s). Various species behave differently under sonication, which is related to structural differences in these species. In the case of Astragaslus compactus and A. rahensus dispersions, as the sonication time increased, the viscosity and particle size of the dispersions decreased, just as in gum Arabic solutions. However, A. gossypinus gum behaved differently compared to the other species. At early stages of sonication (up to 15 s), the viscosity of the dispersions increased sharply and reached its maximum value (106.04 mPa s) as the particle size increased slightly to 275.69 μm. Continuing sonication led to a decrease in the viscosity of the dispersions, though the particle size did not show any changes. This behaviour is thought to be due to the rupture and aggregation of particles. [ABSTRACT FROM AUTHOR]

We consider M/M/1/∞ systems with inventory in which completing each service in the queueing system requires an on-hand inventory. Continuous review (r, Q) policy is considered for the inventory system, and lead times are assumed to be mixed exponentially distributed. During stockout, arriving demands get rejected from the queue and become lost (lost sale situation). We derive stationary distribution of product form of joint queue length and on-hand inventory. The resulting distribution is employed to compute performance measures which can be used to derive the optimal policy. Optimal order size for predetermined reorder policy is initially determined and finally, optimal reorder point and corresponding optimal order size are simultaneously computed for several numerical examples. [ABSTRACT FROM AUTHOR]

Cool roof effectiveness in improving building thermal-energy performance is affected by different variables. In particular, roof insulation level and climate conditions are key parameters influencing cool roofs benefits and whole building energy performance. This work aims at assessing the role of cool roof in the optimum roof configuration, i.e., combination of solar reflectance capability and thermal insulation level, in terms of building energy performance in different climate conditions worldwide. To this aim, coupled dynamic thermal-energy simulation and optimization analysis is carried out. In detail, multi-dimensional optimization of combined building roof thermal insulation and solar reflectance is developed to minimize building annual energy consumption for heating–cooling. Results highlight how a high reflectance roof minimizes annual energy need for a small standard office building in the majority of considered climates. Moreover, building energy performance is more sensitive to roof solar reflectance than thermal insulation level, except for the coldest conditions. Therefore, for the selected building, the optimum roof typology presents high solar reflectance capability (0.8) and no/low insulation level (0.00–0.03 m), except for extremely hot or cold climate zones. Accordingly, this research shows how the classic approach of super-insulated buildings should be reframed for the office case toward truly environmentally friendly buildings. [ABSTRACT FROM AUTHOR]