6,758 research outputs found
Scene-based imperceptible-visible watermarking for HDR video content
This paper presents the High Dynamic Range - Imperceptible Visible Watermarking for HDR video content (HDR-IVW-V) based on scene detection for robust copyright protection of HDR videos using a visually imperceptible watermarking methodology. HDR-IVW-V employs scene detection to reduce both computational complexity and undesired visual attention to watermarked regions. Visual imperceptibility is achieved by finding the region of a frame with the highest hiding capacities on which the Human Visual System (HVS) cannot recognize the embedded watermark. The embedded watermark remains visually imperceptible as long as the normal color calibration parameters are held. HDR-IVW-V is evaluated on PQ-encoded HDR video content successfully attaining visual imperceptibility, robustness to tone mapping operations and image quality preservation
Influence of Ultraviolet Radiation Exposure Time on Styrene-Ethylene-Butadiene-Styrene (SEBS) Copolymer
[EN] The effect of ultraviolet radiation on styrene-ethylene-butadiene-styrene (SEBS) has been studied at different exposures times in order to obtain a better understanding of the mechanism of ageing. The polymer materials were mechanically tested and then their surfaces were analyzed using a scanning electron microscope (SEM) and atomic force microscopy (AFM). Moreover, the optical analysis of contact angle (OCA) was used to evaluate the surface energy (gamma(s)) and the yellowing index (YI) and attenuated total reflectance infrared spectroscopy (ATR-FTIR) were used to observe structural and physical changes in aging SEBS. The results obtained for the SEBS, in relation to the duration of exposure, showed superficial changes that cause a decrease in the surface energy (gamma(s)) and, therefore, a decrease in surface roughness. This led to a reduction in mechanical performance, decreasing the tensile strength by about 50% for exposure times of around 200 hours.This work was supported by the Ministry of Economy and Competitiveness (MINECO) grant number MAT2017-84909-C2-2-R). Daniel Garcia-Garcia acknowledges Generalitat Valenciana (GVA) for financial support through a postdoctoral contract (APOSTD/2019/201).Garcia-Garcia, D.; Crespo, J.; Parres, F.; Samper, M. (2020). Influence of Ultraviolet Radiation Exposure Time on Styrene-Ethylene-Butadiene-Styrene (SEBS) Copolymer. Polymers. 12(4):1-14. https://doi.org/10.3390/polym12040862S114124Picchioni, F., Giorgi, I., Passaglia, E., Ruggeri, G., & Aglietto, M. (2001). Blending of styrene-block-butadiene-block-styrene copolymer with sulfonated vinyl aromatic polymers. Polymer International, 50(6), 714-721. doi:10.1002/pi.692Zhu, J., Birgisson, B., & Kringos, N. (2014). Polymer modification of bitumen: Advances and challenges. European Polymer Journal, 54, 18-38. doi:10.1016/j.eurpolymj.2014.02.005Gupta, S., Chandra, T., Sikder, A., Menon, A., & Bhowmick, A. K. (2008). Accelerated weathering behavior of poly(phenylene ether)-based TPE. Journal of Materials Science, 43(9), 3338-3350. doi:10.1007/s10853-008-2484-6Mamodia, M., Indukuri, K., Atkins, E. T., De Jeu, W. H., & Lesser, A. J. (2008). Hierarchical description of deformation in block copolymer TPEs. Journal of Materials Science, 43(22), 7035-7046. doi:10.1007/s10853-008-3030-2Allen, N. S., Edge, M., Wilkinson, A., Liauw, C. M., Mourelatou, D., Barrio, J., & Martı́nez-Zaporta, M. A. (2000). Degradation and stabilisation of styrene–ethylene–butadiene–styrene (SEBS) block copolymer. Polymer Degradation and Stability, 71(1), 113-122. doi:10.1016/s0141-3910(00)00162-2Costa, P., Ribeiro, S., Botelho, G., Machado, A. V., & Lanceros Mendez, S. (2015). Effect of butadiene/styrene ratio, block structure and carbon nanotube content on the mechanical and electrical properties of thermoplastic elastomers after UV ageing. Polymer Testing, 42, 225-233. doi:10.1016/j.polymertesting.2015.02.002Tomacheski, D., Pittol, M., Lopes, A. P. M., Simões, D. N., Ribeiro, V. F., & Santana, R. M. C. (2017). Effects of Weathering on Mechanical, Antimicrobial Properties and Biodegradation Process of Silver Loaded TPE Compounds. Journal of Polymers and the Environment, 26(1), 73-82. doi:10.1007/s10924-016-0927-8Singh, B., & Sharma, N. (2008). Mechanistic implications of plastic degradation. Polymer Degradation and Stability, 93(3), 561-584. doi:10.1016/j.polymdegradstab.2007.11.008White, C. C., Tan, K. T., Hunston, D. L., Nguyen, T., Benatti, D. J., Stanley, D., & Chin, J. W. (2011). Laboratory accelerated and natural weathering of styrene–ethylene–butylene–styrene (SEBS) block copolymer. Polymer Degradation and Stability, 96(6), 1104-1110. doi:10.1016/j.polymdegradstab.2011.03.003Allen, N. (2004). Photooxidation of styrene–ethylene–butadiene–styrene (SEBS) block copolymer. Journal of Photochemistry and Photobiology A: Chemistry, 162(1), 41-51. doi:10.1016/s1010-6030(03)00311-3Flaris, V., & Stachurski, Z. H. (1992). The effects of processing on the mechanical properties of a polyolefin blend. Polymer International, 27(3), 267-273. doi:10.1002/pi.4990270312Li, Y., Li, L., Zhang, Y., Zhao, S., Xie, L., & Yao, S. (2009). Improving the aging resistance of styrene-butadiene-styrene tri-block copolymer and application in polymer-modified asphalt. Journal of Applied Polymer Science, n/a-n/a. doi:10.1002/app.31458Xu, X., Yu, J., Xue, L., Zhang, C., He, B., & Wu, M. (2017). Structure and performance evaluation on aged SBS modified bitumen with bi- or tri-epoxy reactive rejuvenating system. Construction and Building Materials, 151, 479-486. doi:10.1016/j.conbuildmat.2017.06.102Si Bachir, D., Dekhli, S., & Ait Mokhtar, K. (2016). Rheological Evaluation of Ageing Properties of SEBS Polymer Modified Bitumens. Periodica Polytechnica Civil Engineering, 397-404. doi:10.3311/ppci.7853Awaja, F., Gilbert, M., Kelly, G., Fox, B., & Pigram, P. J. (2009). Adhesion of polymers. Progress in Polymer Science, 34(9), 948-968. doi:10.1016/j.progpolymsci.2009.04.007Poisson, C., Hervais, V., Lacrampe, M. F., & Krawczak, P. (2006). Optimization of PE/binder/PA extrusion blow-molded films. II. Adhesion properties improvement using binder/EVA blends. Journal of Applied Polymer Science, 101(1), 118-127. doi:10.1002/app.22407Zhang, H., Guo, W., Yu, Y., Li, B., & Wu, C. (2007). Structure and properties of compatibilized recycled poly(ethylene terephthalate)/linear low density polyethylene blends. European Polymer Journal, 43(8), 3662-3670. doi:10.1016/j.eurpolymj.2007.05.001Guerrica-Echevarría, G., Eguiazábal, J. I., & Nazábal, J. (2007). Influence of compatibilization on the mechanical behavior of poly(trimethylene terephthalate)/poly(ethylene–octene) blends. European Polymer Journal, 43(3), 1027-1037. doi:10.1016/j.eurpolymj.2006.11.036Chang, Y.-W., Shin, J.-Y., & Ryu, S. H. (2004). Preparation and properties of styrene–ethylene/butylene–styrene(SEBS)–clay hybrids. Polymer International, 53(8), 1047-1051. doi:10.1002/pi.1480Chen, W.-C., Lai, S.-M., & Chen, C.-M. (2008). Preparation and properties of styrene-ethylene-butylene-styrene block copolymer/clay nanocomposites: I. Effect of clay content and compatibilizer types. Polymer International, 57(3), 515-522. doi:10.1002/pi.2377Qin, R.-Y., & Schreiber, H. P. (1999). Adhesion at partially restructured polymer surfaces. Colloids and Surfaces A: Physicochemical and Engineering Aspects, 156(1-3), 85-93. doi:10.1016/s0927-7757(99)00061-8Zhang, X., Xie, F., Pen, Z., Zhang, Y., Zhang, Y., & Zhou, W. (2002). Effect of nucleating agent on the structure and properties of polypropylene/poly(ethylene–octene) blends. European Polymer Journal, 38(1), 1-6. doi:10.1016/s0014-3057(01)00182-3Beholz, L. G., Aronson, C. L., & Zand, A. (2005). Adhesion modification of polyolefin surfaces with sodium hypochlorite in acidic media. Polymer, 46(13), 4604-4613. doi:10.1016/j.polymer.2005.03.086Kinloch, A. J. (1980). The science of adhesion. Journal of Materials Science, 15(9), 2141-2166. doi:10.1007/bf00552302Lippert, T., & Dickinson, J. T. (2003). Chemical and Spectroscopic Aspects of Polymer Ablation: Special Features and Novel Directions. Chemical Reviews, 103(2), 453-486. doi:10.1021/cr010460qVan der Leeden, M. C., & Frens, G. (2002). Surface Properties of Plastic Materials in Relation to Their Adhering Performance. Advanced Engineering Materials, 4(5), 280-289. doi:10.1002/1527-2648(20020503)4:53.0.co;2-zPukánszky, B. (2005). Interfaces and interphases in multicomponent materials: past, present, future. European Polymer Journal, 41(4), 645-662. doi:10.1016/j.eurpolymj.2004.10.035Tjong, S. C., Xu, S.-A., & Mai, Y.-W. (2003). Journal of Materials Science, 38(2), 207-215. doi:10.1023/a:1021132725370Sanchis, R., Fenollar, O., García, D., Sánchez, L., & Balart, R. (2008). Improved adhesion of LDPE films to polyolefin foams for automotive industry using low-pressure plasma. International Journal of Adhesion and Adhesives, 28(8), 445-451. doi:10.1016/j.ijadhadh.2008.04.002Brockmann, W., & Hüther, R. (1996). Adhesion mechanisms of pressure sensitive adhesives. International Journal of Adhesion and Adhesives, 16(2), 81-86. doi:10.1016/0143-7496(96)89797-1Brovko, O., Rosso, P., & Friedrich, K. (2002). Journal of Materials Science Letters, 21(4), 305-308. doi:10.1023/a:1017936206578Court, R. S., Sutcliffe, M. P. F., & Tavakoli, S. M. (2001). Ageing of adhesively bonded joints—fracture and failure analysis using video imaging techniques. International Journal of Adhesion and Adhesives, 21(6), 455-463. doi:10.1016/s0143-7496(01)00022-7Komvopoulos, K. (2003). Adhesion and friction forces in microelectromechanical systems: mechanisms, measurement, surface modification techniques, and adhesion theory. Journal of Adhesion Science and Technology, 17(4), 477-517. doi:10.1163/15685610360554384Pijpers, A. ., & Meier, R. J. (2001). Adhesion behaviour of polypropylenes after flame treatment determined by XPS(ESCA) spectral analysis. Journal of Electron Spectroscopy and Related Phenomena, 121(1-3), 299-313. doi:10.1016/s0368-2048(01)00341-3Yu, S., Hu, H., Zhang, Y., & Liu, Y. (2008). Effect of transfer film on tribological behavior of polyamide 66-based binary and ternary nanocomposites. Polymer International, 57(3), 454-462. doi:10.1002/pi.2337Żenkiewicz, M. (2007). Comparative study on the surface free energy of a solid calculated by different methods. Polymer Testing, 26(1), 14-19. doi:10.1016/j.polymertesting.2006.08.005Kumar, S., & Misra, R. K. (2007). Analysis of Banana Fibers Reinforced Low‐density Polyethylene/Poly(Є‐caprolactone) Composites. Soft Materials, 4(1), 1-13. doi:10.1080/15394450600823040Fowkes, F. ., McCarthy, D. ., & Mostafa, M. . (1980). Contact angles and the equilibrium spreading pressures of liquids on hydrophobic solids. Journal of Colloid and Interface Science, 78(1), 200-206. doi:10.1016/0021-9797(80)90508-1Owens, D. K., & Wendt, R. C. (1969). Estimation of the surface free energy of polymers. Journal of Applied Polymer Science, 13(8), 1741-1747. doi:10.1002/app.1969.070130815Zhao, Y., Tang, S., Myung, S.-W., Lu, N., & Choi, H.-S. (2006). Effect of washing on surface free energy of polystyrene plate treated by RF atmospheric pressure plasma. Polymer Testing, 25(3), 327-332. doi:10.1016/j.polymertesting.2005.12.007Hänni‐Ciunel, K., Findenegg, G. H., & von Klitzing, R. (2007). Water Contact Angle On Polyelectrolyte‐Coated Surfaces: Effects of Film Swelling and Droplet Evaporation. Soft Materials, 5(2-3), 61-73. doi:10.1080/15394450701554452Radovanovic, E., Carone, E., & Gonçalves, M. . (2004). Comparative AFM and TEM investigation of the morphology of nylon6-rubber blends. Polymer Testing, 23(2), 231-237. doi:10.1016/s0142-9418(03)00099-0Drnovská, H., Lapčík, L., Buršíková, V., Zemek, J., & Barros-Timmons, A. M. (2003). Surface properties of polyethylene after low-temperature plasma treatment. Colloid and Polymer Science, 281(11), 1025-1033. doi:10.1007/s00396-003-0871-8Lehocký, M., Drnovská, H., Lapčı́ková, B., Barros-Timmons, A. ., Trindade, T., Zembala, M., & Lapčı́k, L. (2003). Plasma surface modification of polyethylene. Colloids and Surfaces A: Physicochemical and Engineering Aspects, 222(1-3), 125-131. doi:10.1016/s0927-7757(03)00242-5Ortiz-Magán, A. B., Pastor-Blas, M. M., Ferrándiz-Gómez, T. P., Morant-Zacarés, C., & Martín-Martínez, J. M. (2001). Plasmas and Polymers, 6(1/2), 81-105. doi:10.1023/a:1011352903775Mailhot, B., & Gardette, J. L. (1992). Polystyrene photooxidation. 2. A pseudo wavelength effect. Macromolecules, 25(16), 4127-4133. doi:10.1021/ma00042a013Mailhot, B., Jarroux, N., & Gardette, J.-L. (2000). Comparative analysis of the photo-oxidation of polystyrene and poly(α-methylstyrene). Polymer Degradation and Stability, 68(3), 321-326. doi:10.1016/s0141-3910(00)00016-1Luengo, C., Allen, N. S., Edge, M., Wilkinson, A., Parellada, M. D., Barrio, J. A., & Santa, V. R. (2006). Photo-oxidative degradation mechanisms in styrene–ethylene–butadiene–styrene (SEBS) triblock copolymer. Polymer Degradation and Stability, 91(4), 947-956. doi:10.1016/j.polymdegradstab.2005.06.017Han, X., Zhou, L., Liu, H., & Hu, Y. (2007). Effect of in situ oxidization with potassium permanganate on the morphologies of SEBS membranes. Polymer Degradation and Stability, 92(1), 75-85. doi:10.1016/j.polymdegradstab.2006.09.006Allen, N. S., Edge, M., Mourelatou, D., Wilkinson, A., Liauw, C. M., Dolores Parellada, M., … Ruiz Santa Quiteria, V. (2003). Influence of ozone on styrene–ethylene–butylene–styrene (SEBS) copolymer. Polymer Degradation and Stability, 79(2), 297-307. doi:10.1016/s0141-3910(02)00293-8Fombuena, V., Balart, J., Boronat, T., Sánchez-Nácher, L., & Garcia-Sanoguera, D. (2013). Improving mechanical performance of thermoplastic adhesion joints by atmospheric plasma. Materials & Design, 47, 49-56. doi:10.1016/j.matdes.2012.11.031Sanchis, M. R., Calvo, O., Fenollar, O., Garcia, D., & Balart, R. (2008). Characterization of the surface changes and the aging effects of low-pressure nitrogen plasma treatment in a polyurethane film. Polymer Testing, 27(1), 75-83. doi:10.1016/j.polymertesting.2007.09.002Sheikhy, H., Shahidzadeh, M., Ramezanzadeh, B., & Noroozi, F. (2013). Studying the effects of chain extenders chemical structures on the adhesion and mechanical properties of a polyurethane adhesive. Journal of Industrial and Engineering Chemistry, 19(6), 1949-1955. doi:10.1016/j.jiec.2013.03.008Švab, I., Musil, V., Šmit, I., & Makarovič, M. (2007). Mechanical properties of wollastonite-reinforced polypropylene composites modified with SEBS and SEBS-g-MA elastomers. Polymer Engineering & Science, 47(11), 1873-1880. doi:10.1002/pen.20897Sanchis, M. R., Blanes, V., Blanes, M., Garcia, D., & Balart, R. (2006). Surface modification of low density polyethylene (LDPE) film by low pressure O2 plasma treatment. European Polymer Journal, 42(7), 1558-1568. doi:10.1016/j.eurpolymj.2006.02.001Ganguly, A., & Bhowmick, A. K. (2009). Effect of polar modification on morphology and properties of styrene-(ethylene-co-butylene)-styrene triblock copolymer and its montmorillonite clay-based nanocomposites. Journal of Materials Science, 44(3), 903-918. doi:10.1007/s10853-008-3183-
Noise control by sonic crystal barriers made of recycled materials
A systematic study of noise barriers based on sonic crystals made of
cylinders that use recycled materials like absorbing component is here
reported. The barriers consist of only three rows of perforated metal shells
filled with rubber crumb. Measurements of reflectance and transmittance by
these barriers are reported. Their attenuation properties result from a
combination of sound absorption by the rubber crumb and reflection by the
periodic distribution of scatterers. It is concluded that porous cylinders can
be used as building blocks whose physical parameters can be optimized in order
to design efficient barriers adapted to different noisy environments
Meta-analysis of Arabidopsis KANADI1 direct target genes identifies basic growth-promoting module acting upstream of hormonal signaling pathways
An intricate network of antagonistically acting transcription factors mediates the formation of a flat leaf lamina of Arabidopsis (Arabidopsis thaliana) plants. In this context, members of the class III homeodomain leucine zipper (HD-ZIPIII) transcription factor family specify the adaxial domain (future upper side) of the leaf, while antagonistically acting KANADI transcription factors determine the abaxial domain (future lower side). Here, we used a messenger RNA sequencing approach to identify genes regulated by KANADI1 (KAN1) and subsequently performed a meta-analysis combining our data sets with published genome-wide data sets. Our analysis revealed that KAN1 acts upstream of several genes encoding auxin biosynthetic enzymes. When exposed to shade, we found three YUCCA genes, YUC2, YUC5, and YUC8, to be transcriptionally up-regulated, which correlates with an increase in the levels of free auxin. When ectopically expressed, KAN1 is able to transcriptionally repress these three YUC genes and thereby block shade-induced auxin biosynthesis. Consequently, KAN1 is able to strongly suppress shade-avoidance responses. Taken together, we hypothesize that HD-ZIPIII/KAN form the basis of a basic growth-promoting module. Hypocotyl extension in the shade and outgrowth of new leaves both involve auxin synthesis and signaling, which are under the direct control of HD-ZIPIII/KAN.This work was supported by the European Union (Marie-Curie International Reintegration grant no. 256502 to S.W.), the Deutsche Forschungsgemeinschaft Collaborative Research Centre (grant no. SFB1101 to S.W.), the European Research Council (grant no. 336295 to S.W.), and the Spanish MINECO (grant no. BIO2011–23489 to J.F.M.-G.).Peer reviewe
Microwave and Millimeter Wave Techniques
Contains reports on two research project.Joint Services Electronics Program (Contract DAABO7-76-C-1400
The Soft-Excess in Mrk 509: Warm Corona or Relativistic Reflection?
We present the analysis of the first NuSTAR observations ( ks),
simultaneous with the last SUZAKU observations ( ks), of the active
galactic nucleus of the bright Seyfert 1 galaxy Mrk 509. The time-averaged
spectrum in the keV X-ray band is dominated by a power-law continuum
(), a strong soft excess around 1 keV, and signatures of
X-ray reflection in the form of Fe K emission ( keV), an Fe K
absorption edge ( keV), and a Compton hump due to electron scattering
( keV). We show that these data can be described by two very
different prescriptions for the soft excess: a warm ( keV) and
optically thick () Comptonizing corona, or a relativistically
blurred ionized reflection spectrum from the inner regions of the accretion
disk. While these two scenarios cannot be distinguished based on their fit
statistics, we argue that the parameters required by the warm corona model are
physically incompatible with the conditions of standard coronae. Detailed
photoionization calculations show that even in the most favorable conditions,
the warm corona should produce strong absorption in the observed spectrum. On
the other hand, while the relativistic reflection model provides a satisfactory
description of the data, it also requires extreme parameters, such as maximum
black hole spin, a very low and compact hot corona, and a very high density for
the inner accretion disk. Deeper observations of this source are thus necessary
to confirm the presence of relativistic reflection, and to further understand
the nature of its soft excess.Comment: Accepted for publication in ApJ, 18 pages, 7 figure
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