Fuzzy Multicriteria Model for Ranking Suppliers in Manufacturing Company

By using the methods of multi-criteria analysis it is possible to make decisions which have significant influence on companies\u27 business. The aim of this paper is to evaluate different suppliers using the integrated model that recognizes a combination of fuzzy AHP (Analytical Hierarchy Process) and the COPRAS method. Based on six criteria, the expert team was formed to compare them, so determination of their significance is being done with fuzzy AHP method. Expert team also compares suppliers according to each criterion and on the base of triangular fuzzy numbers. Based on their inputs, COPRAS method is used to estimate potential solutions. Suggested model accomplishes certain advantages in comparison with previously used traditional models which were used to make decisions about evaluation and choice of supplier. It is vital to make the right decision when selecting a supplier, because the optimal choice ensures lower cost and higher quality of the product itself, and therefore more competitiveness in the market. This work is licensed under a&nbsp;Creative Commons Attribution-NonCommercial 4.0 International License.</p

Fuzzy Multicriteria Model for Ranking Suppliers in Manufacturing Company

By using the methods of multi-criteria analysis it is possible to make decisions which have significant influence on companies\u27 business. The aim of this paper is to evaluate different suppliers using the integrated model that recognizes a combination of fuzzy AHP (Analytical Hierarchy Process) and the COPRAS method. Based on six criteria, the expert team was formed to compare them, so determination of their significance is being done with fuzzy AHP method. Expert team also compares suppliers according to each criterion and on the base of triangular fuzzy numbers. Based on their inputs, COPRAS method is used to estimate potential solutions. Suggested model accomplishes certain advantages in comparison with previously used traditional models which were used to make decisions about evaluation and choice of supplier. It is vital to make the right decision when selecting a supplier, because the optimal choice ensures lower cost and higher quality of the product itself, and therefore more competitiveness in the market. This work is licensed under a&nbsp;Creative Commons Attribution-NonCommercial 4.0 International License.</p

Supporting programs for the development of cooperatives in the Republic of Serbia

Serbia is among few countries that have two ministries, the Ministry of Agriculture, Forestry and Water Management and the Ministry of Rural Welfare, active in solving actual problems linked to living and working conditions in rural space. Establishment of cooperatives, or joined action of rural population could enable developmental processes in rural areas. Both ministries offer certain programs of public support focused on cooperatives advancement or establishment, and indirectly securing the competitiveness and sustainability of cooperative members (i.e. mainly family farms). The main research goal is observing the economic impact of the one of program support lines of the Ministry of Rural Welfare directed to development of cooperatives, and further prevention of disappearing of rural communities in Serbia. Analysis shows that mentioned support has turned over the previous trend of shutting down the cooperatives into situation when over 1,100 new agricultural cooperatives have been established in last several years. Additionally, derived results initiate certain recommendations, useful both for policy makers and cooperatives

Essential Oils as Feed AdditivesFuture Perspectives

The inconsistency of phytogenic feed additives' (PFA) effects on the livestock industry poses a risk for their use as a replacement for antibiotic growth promoters. The livestock market is being encouraged to use natural growth promotors, but information is limited about the PFA mode of action. The aim of this paper is to present the complexity of compounds present in essential oils (EOs) and factors that influence biological effects of PFA. In this paper, we highlight various controls and optimization parameters that influence the processes for the standardization of these products. The chemical composition of EOs depends on plant genetics, growth conditions, development stage at harvest, and processes of extracting active compounds. Their biological effects are further influenced by the interaction of phytochemicals and their bioavailability in the gastrointestinal tract of animals. PFA effects on animal health and production are also complex due to various EO antibiotic, antioxidant, anti-quorum sensing, anti-inflammatory, and digestive fluids stimulating activities. Research must focus on reliable methods to identify and control the quality and effects of EOs. In this study, we focused on available microencapsulation techniques of EOs to increase the bioavailability of active compounds, as well as their application in the animal feed additive industry

Ultrafast humidity sensor based on liquid phase exfoliated graphene

Humidity sensing is important to a variety of technologies and industries, ranging from environmental and industrial monitoring to medical applications. Although humidity sensors abound, few available solutions are thin, transparent, compatible with large-area sensor production and flexible, and almost none are fast enough to perform human respiration monitoring through breath detection or real-time finger proximity monitoring via skin humidity sensing. This work describes chemiresistive graphene-based humidity sensors produced in few steps with facile liquid phase exfoliation (LPE) followed by Langmuir-Blodgett assembly that enables active areas of practically any size. The graphene sensors provide a unique mix of performance parameters, exhibiting resistance changes up to 10% with varying humidity, linear performance over relative humidity (RH) levels between 8% and 95%, weak response to other constituents of air, flexibility, transparency of nearly 80%, and response times of 30 ms. The fast response to humidity is shown to be useful for respiration monitoring and real-time finger proximity detection, with potential applications in flexible touchless interactive panels.Comment: 18 pages, 13 figure

Comparative Investigation of the Efficacy of Three Different Adsorbents against OTA-Induced Toxicity in Broiler Chickens

The aim of our study was to determine the efficacy of three different adsorbents, inorganic (modified zeolite), organic (esterified glucomannans) and mixed (inorganic and organic components, with the addition of enzymes), in protecting broilers from the toxic effects of ochratoxin A in feed. Broilers were fed diets containing 2 mg/kg of ochratoxin A (OTA) and supplemented with adsorbents at the recommended concentration of 2 g/kg for 21 days. The presence of OTA led to a notable reduction in body weight, lower weight gain, increased feed conversion and induced histopathological changes in the liver and kidneys. The presence of inorganic, organic and mixed adsorbents in contaminated feed only partially reduced the negative effects of OTA on the broiler performances. Broilers that were fed with adsorbent-supplemented feed reached higher body weight (17.96%, 19.09% and 13.59%), compared to the group that received only OTA. The presence of adsorbents partially alleviated the reduction in feed consumption (22.68%, 12.91% and 10.59%), and a similar effect was observed with feed conversion. The applied adsorbents have also reduced the intensity of histopathological changes caused by OTA; however, they were not able to prevent their onset. After the withdrawal of the toxin and adsorbents from the feed (21-42 days), all previously observed disturbances in broilers were reduced, but more remarkably in broilers fed with adsorbents

Monolayer Gas Adsorption on Graphene-Based Materials: Surface Density of Adsorption Sites and Adsorption Capacity

Surface density of adsorption sites on an adsorbent (including affinity-based sensors) is one of the basic input parameters in modeling of process kinetics in adsorption based devices. Yet, there is no simple expression suitable for fast calculations in current multiscale models. The published experimental data are often application-specific and related to the equilibrium surface density of adsorbate molecules. Based on the known density of adsorbed gas molecules and the surface coverage, both of these in equilibrium, we obtained an equation for the surface density of adsorption sites. We applied our analysis to the case of pristine graphene and thus estimated molecular dynamics of adsorption on it. The monolayer coverage was determined for various pressures and temperatures. The results are verified by comparison with literature data. The results may be applicable to modeling of the surface density of adsorption sites for gas adsorption on other homogeneous crystallographic surfaces. In addition to it, the obtained analytical expressions are suitable for training artificial neural networks determining the surface density of adsorption sites on a graphene surface based on the known binding energy, temperature, mass of adsorbate molecules and their affinity towards graphene. The latter is of interest for multiscale modelling

Analysis of acoustic cloaks for anti-sonar camouflage based on local resonance in acoustic metamaterials

Non-visual camouflage plays a significant role in the art of military deception. One of the fields of interest is auditory camouflage, where the goal is to remove the acoustic signature of an object, whether it is generated by the object itself or scattered from a surveillance device like sonar. A recently proposed approach to auditory camouflage is acoustic cloaking, where the object is made 'invisible' in acoustic sense by surrounding it with a cloak of acoustic metamaterial. Acoustic metamaterial is basically an artificial structure tailored to enable control of acoustic wave dispersion through Bragg scattering, where the features of the structure have subwavelength dimensions. The operation of an acoustic cloak is based on negative effective dynamic mass and bulk modulus which can be obtained by local resonances. This leads to a possibility to fully tailor the path of acoustic waves (infrasound, audible waves or ultrasound) around the camouflaged object, effectively enabling one to make waves avoid the object and render it invisible. In this contribution we perform a full finite element modeling of the elements of an acoustic cloak, analyze it and consider coordinate transformation necessary to ensure acoustic concealment of a macroscopic object. We investigated spatial distribution of acoustic waves for two different scatterers, one of them being a cylindrical object with circular basis, another one a cylinder with elliptical basis. All our calculations were performed for a realistic sea water medium, modeled by an empirical formula. We considered the frequency dispersion of the acoustic field in different spectral ranges, from infrasound to audible frequencies. For elliptic cloaks we applied a very simple approach that nevertheless furnished better acoustic cloaking than some more complex layered profiles previously published

The role of copper doping on physicochemical properties of bismuth vanadate

Production of gasses such as hydrogen and oxygen on a large scale is of the great importance both in industry and in environmental protection. To achieve it, photoelectrochemical (PEC) water splitting has been regarded as promising method and the developement of new semiconductors holds a key role to the efficent application. Due to its great light harvesting ability, band edge positions and low-cost synthesis method, bismuth vanadate (BiVO4; BVO) has been intensively studied as a photoanode material for water splitting. To overcome limitations such as charge carriers recombination, material should be doped with different transition metal elements. In this work physicochemical properties of pristine and 1%-, 2.5%- and 5%- Cu-doped BVO powders, solvothermaly synthesized at 180°C for 20 h, were reported. X-ray diffraction (XRD) study indicates that, depending on the doping level, the material exists in monoclinic or tetragonal scheelite phase, but mixed phase composition was also observed. Pure monoclinic and tetragonal phase was formed in a case of pristine and 1% doped sample, respectively, while 2.5%- and 5%- Cu-doped BVO exhibit presence of both phases. Scanning electron microscopy (SEM) reveals that sample with monoclinic phase consists of irregular worm-like morphology, while morphology of tetragonal samples was mostly spherical. For 2.5%- and 5%- Cu-doped samples a combination of prismatic and spherical shape morphology was observed. Local structure of material was examined with Raman spectroscopy and the results were in accordance with XRD study where band positions well matched the phase composition. Optical properties were characterized with UV-Vis Diffuse Reflectance Spectroscopy (DRS) and Photoluminescence (PL) spectroscopy. The band gap of monoclinic samples was in range 2.4-2.5 eV, while band gap of sample with tetragonal phase has band gap was between 2.8 and 3 eV. Dual phase samples had two different band gaps that originate from presence of both phases. Based on the results obtained from the PL spectra, monoclinic samples possess better recombination features than tetragonal ones. Photoelectrochemical measurements of BVO samples imply that doping of material improves performance towards oxygen evolution reaction.Twentieth Young Researchers’ Conference - Materials Science and Engineering: Program and the Book of Abstracts; November 30 – December 2, 2022, Belgrade, Serbi

Application of experimental design in the examination of the dissolution rate of carbamazepine from formulations. Characterization of the optimal formulation by DSC, TGA, FT-IR and PXRD analysis

Poor solubility is one of the key reasons for the poor bioavailability of carbamazepine drugs. This study considers formulation of solid surfactant systems with carbamazepine, in order to increase its dissolution rate. Solid-state surfactant systems were formed by application of fractional experimental design. Poloxamer 237 and Poloxamer 338 were used as the surfactants and Brij (R) 35 was used as the co-surfactant. The ratios of the excipients and carbamazepine were varied and their effects on the dissolution rate of carbamazepine were examined. Moreover, the effects of the addition of natural (diatomite) and a synthetic adsorbent carrier (Neusilin (R) UFL2) on the dissolution rate of carbamazepine were also tested. The prepared surfactant systems were characterized and the influences of the excipients on possible changes of the polymorphous form of carbamazepine examined by application of analytical techniques (DSC, TGA, FT-IR and PXRD). It was determined that an appropriate selection of the excipient type and ratio could provide a significant increase in the carbamazepine dissolution rate. By application of analytical techniques, it was found that the employed excipients induce a transition of carbamazepine into the amorphous form and that the selected sample was stable for three months, when kept under ambient conditions