188 research outputs found

    Human Skin Detection Using RGB, HSV and YCbCr Color Models

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    Human Skin detection deals with the recognition of skin-colored pixels and regions in a given image. Skin color is often used in human skin detection because it is invariant to orientation and size and is fast to process. A new human skin detection algorithm is proposed in this paper. The three main parameters for recognizing a skin pixel are RGB (Red, Green, Blue), HSV (Hue, Saturation, Value) and YCbCr (Luminance, Chrominance) color models. The objective of proposed algorithm is to improve the recognition of skin pixels in given images. The algorithm not only considers individual ranges of the three color parameters but also takes into ac- count combinational ranges which provide greater accuracy in recognizing the skin area in a given image.Comment: ICCASP/ICMMD-2016. Published by Atlantic Press. Part of series: AISR ISBN: 978-94-6252-305-0 ISSN: 1951-685

    Ispitivanje vosku sličnih svojstava ibuprofena kao veziva

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    The study investigates ibuprofen with wax-like properties as a multifunctional agent (as an active component and as a melt binder). Binding efficiency was compared with granules prepared by wet granulation using polyvinylpyrollidone (PVP K-30) as a binder for micromeritic, physical and mechanical properties such as angle of repose, particle size distribution Carr’s index, Hausner’s ratio, crushing strength, percentage fines, Heckel plot study and tensile strength. To check the binder distribution during melt granulation, content uniformity was determined. To check changes in the physical state of ibuprofen, XRPD, DSC and FTIR studies were carried out. The present study underlines the fact that ibuprofen may be adopted as a binder in ibuprofen formulations using the melt granulation techniqueSvrha rada je ispitivanje vosku sličnih svojstava ibuprofena, tvari s višeznačnom funkcijom (ljekovita tvar i vezivo pri granulaciji). Vezivna svojstva uspoređivana su s granulama pripravljenim vlažnom granulacijom s polivinilpirolidonom (PVP K-30) kao vezivom, ispitivanjem mikrometričkih, fizikalnih i mehaničkih svojstava kao što su sipkost materijala, Carrov indeks distribucije veličine čestica, Hausnerov parameter, otpornost na vlak. Da bi se ispitala distribucija veziva tijekom granulacije taljenjem određivana je ujednačenost sadržaja. Za praćenje promjena fizikalnih svojstava ibuprofena snimljeni su XRPD, DSC, FTIR spektri. Istraživanja ukazuju da se ibuprofen može koristiti kao vezivo u ljekovitim pripravcima ibuprofena u kojima se primjenjuje granulacija taljenjem

    TASTE ABATEMENT AND CHARACTERIZATION OF DISPERSIBLE TABLETS OF ARTEMETHER PREPARED BY HOT MELT EXTRUSION

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    Objective: The aim of this study was to formulate and evaluate a taste-masked formulation using hot melt extrusion approach for artemether.Methods: Taste masking of artemether was done by preparing solid dispersion with coating polymer kollicoatsmartseal 30D using hot melt extrusion. The prepared solid dispersion was subjected to taste masking evaluation like sensory evaluation parameters against five levels set for taste evaluation using artemether as control standard along with in vitro release studies in simulated salivery fluid. After taste evaluation of solid dispersion was subjected to the formulation of dispersible tablets by direct compression method. The final taste masking evaluation of dispersible tablets of solid dispersion containing artemether were done by a sensory evaluation panel of nine members along with in vitro release study in simulated salivary and gastric fluid.Results: The percent drug content was found 35.09±0.06 % in solid dispersion. The drug excipients compatibility studies performed with the help of FTIR instrument and DSC that indicates there were no interactions between drug and polymers. Solid dispersions (1:1, 1:2, 1:3 drug polymer ratio) of artemether were evaluated by sensory evaluation panel from which 1:3 drug: polymer solid dispersion was found more palatable. Release rate study in simulated salivary fluid shown no release but shows release of drug in simulated gastric fluids which indicates that the drug was taste masked. The optimized batch of dispersible tablets (F1) were subjected for evaluation parameters like dispersion time (70±1.90), wetting time (63±1.86), etc. Dissolution studies of optimized formulation indicated that the polymer does not allow drug to release in simulated salivery pH 6.8 but shows immediate release in simulated gastric pH which also confirms taste masking efficiency of polymer. Final optimized F1 batch evaluated for taste masking evaluation by sensory evaluation panel using pure drug as control standard found to be palatable.Conclusion: It may be concluded that kollicoatsmartseal 30D could mask the taste of the drug in salivary pH and shows drug release at gastric pH which confirms its efficiency for taste masking

    Ispitivanje vosku sličnih svojstava ibuprofena kao veziva

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    The study investigates ibuprofen with wax-like properties as a multifunctional agent (as an active component and as a melt binder). Binding efficiency was compared with granules prepared by wet granulation using polyvinylpyrollidone (PVP K-30) as a binder for micromeritic, physical and mechanical properties such as angle of repose, particle size distribution Carr’s index, Hausner’s ratio, crushing strength, percentage fines, Heckel plot study and tensile strength. To check the binder distribution during melt granulation, content uniformity was determined. To check changes in the physical state of ibuprofen, XRPD, DSC and FTIR studies were carried out. The present study underlines the fact that ibuprofen may be adopted as a binder in ibuprofen formulations using the melt granulation techniqueSvrha rada je ispitivanje vosku sličnih svojstava ibuprofena, tvari s višeznačnom funkcijom (ljekovita tvar i vezivo pri granulaciji). Vezivna svojstva uspoređivana su s granulama pripravljenim vlažnom granulacijom s polivinilpirolidonom (PVP K-30) kao vezivom, ispitivanjem mikrometričkih, fizikalnih i mehaničkih svojstava kao što su sipkost materijala, Carrov indeks distribucije veličine čestica, Hausnerov parameter, otpornost na vlak. Da bi se ispitala distribucija veziva tijekom granulacije taljenjem određivana je ujednačenost sadržaja. Za praćenje promjena fizikalnih svojstava ibuprofena snimljeni su XRPD, DSC, FTIR spektri. Istraživanja ukazuju da se ibuprofen može koristiti kao vezivo u ljekovitim pripravcima ibuprofena u kojima se primjenjuje granulacija taljenjem

    Degradation Kinetics of Polycarbonate Composites: Kinetic Parameters and Artificial Neural Network

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    In order to design a reactor, kinetics of degradation of polycarbonate/CaCO3 composites was investigated here by thermogravimetric analysis (TGA), applying model-free and modelistic methods together, to obtain E, A, ΔS*, ΔH* and ΔG* (kinetic parameters). The system was tested with all the mechanisms available using non-isothermal modelistic method (Coats-Redfern). This approach allowed choosing the models, which are otherwise difficult to decide upon simply based on regression fit methods. The mechanism proposed was a simple nth order. Application of artificial neural network supported in designing a neural network could lead to a quick determination of kinetic parameters. This work is licensed under a Creative Commons Attribution 4.0 International License

    Effect of the cadmium chloride treatment on RF sputtered Cd0.6Zn0.4Te films for application in multijunction solar cells

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    Single phase Cd0.6 Zn 0.4Te (CdZnTe) films of 1 μm thickness were deposited by radio frequency planar magnetron sputter deposition on commercial soda lime glass samples coated with fluorine-doped tin oxide and cadmium sulphide (CdS). The stack was then treated with cadmium chloride (CdCl2) at different temperatures using a constant treatment time. The effect of the CdCl2 treatment was studied using optical, materials, and electrical characterization of the samples and compared with the as-deposited CdZnTe film with the same stack configuration. The band gap deduced from Tauc plots on the as-deposited CdZnTe thin film was 1.72 eV. The deposited film had good crystalline quality with a preferred orientation along the {111} plane. After the CdCl2 treatment, the absorption edge shifted toward longer wavelength region and new peaks corresponding to cadmium telluride (CdTe) emerged in the x-ray diffraction pattern. This suggested loss of zinc after the CdCl2 treatment. The cross sectional transmission electron microscope images of the sample treated at 400 °C and the energy dispersive elemental maps revealed the absence of chlorine along the grain boundaries of CdZnTe and residual CdTe. The presence of chlorine in the CdTe devices plays a vital role in drastically improving the device performance which was not observed in CdZnTe samples treated with CdCl2. The loss of zinc from the surface and incomplete recrystallization of the grains together with the presence of high densities of stacking faults were observed. The surface images using scanning electron microscopy showed that the morphology of the grains changed from small spherical shape to large grains formed due to the fusion of small grains with distinct grain boundaries visible at the higher CdCl2 treatment temperatures. The absence of chlorine along the grain boundaries, incomplete recrystallization and distinct grain boundaries is understood to cause the poor performance of the fabricated devices

    Activation of thin film CdTe solar cells using a cadmium bromide treatment

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    The activation of CdTe with a cadmium chloride annealing treatment is a vital step in the fabrication of high efficiency solar cells. Thin film MZO/CdTe cells have been activated using CdBr2 instead of CdCl2 with a lower activation process temperature. Using this method, CdBr2 does activate the cell as revealed by J-V and EQE measurements. TEM and EDX elemental maps from device cross-sections confirm that bromine is present in the grain boundaries. TEM shows that the treatment removes stacking faults at 425 °C. CdBr2 treatment resulted in a relatively modest conversion efficiency of 5.49% when treated at 375 °C. Nevertheless, the experiments shed further light on the mechanisms involved in the activation

    CdCl2 passivation of polycrystalline CdMgTe and CdZnTe absorbers for tandem photovoltaic cells

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    © 2018 Author(s). As single-junction silicon solar cells approach their theoretical limits, tandems provide the primary path to higher efficiencies. CdTe alloys can be tuned with magnesium (CdMgTe) or zinc (CdZnTe) for ideal tandem pairing with silicon. A II-VI/Si tandem holds the greatest promise for inexpensive, high-efficiency top cells that can be quickly deployed in the market using existing polycrystalline CdTe manufacturing lines combined with mature silicon production lines. Currently, all high efficiency polycrystalline CdTe cells require a chloride-based passivation process to passivate grain boundaries and bulk defects. This research examines the rich chemistry and physics that has historically limited performance when extending Cl treatments to polycrystalline 1.7-eV CdMgTe and CdZnTe absorbers. A combination of transmittance, quantum efficiency, photoluminescence, transmission electron microscopy, and energy-dispersive X-ray spectroscopy clearly reveals that during passivation, Mg segregates and out-diffuses, initially at the grain boundaries but eventually throughout the bulk. CdZnTe exhibits similar Zn segregation behavior; however, the onset and progression is localized to the back of the device. After passivation, CdMgTe and CdZnTe can render a layer that is reduced to predominantly CdTe electro-optical behavior. Contact instabilities caused by inter-diffusion between the layers create additional complications. The results outline critical issues and paths for these materials to be successfully implemented in Si-based tandems and other applications

    Advanced co-sublimation hardware for deposition of graded ternary alloys in thin-film applications

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    © 2018 IEEE. CdTe photovoltaic devices with efficiency over 22% have been demonstrated. Sublimated CdTe photovoltaics with efficiency over 19% have been reported using graded alloying of Se in CdTe absorber films. Grading of alloy films has been identified as an important characteristic to achieve higher device performance using more complex device structures. An advanced co-sublimation source has been designed and developed to deposit highly controlled CdTe based ternary alloys. An advanced shutter mechanism enables changing the composition of the deposited films during sublimation. The hardware used for advanced co-sublimation and initial materials characterization is presented in this study
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