Convolutional neural network with joint stepwise character/word modeling based system for scene text recognition

Multimedia Tools and Applications - Text recognition in the wild is a challenging task in the field of computer vision and machine learning. Existing optical character recognition engines cannot...     

High efficiency of methylene blue removal using a novel low-cost acid treated forest wastes,Cupressus semperirens cones: Experimental results and modeling

The removal of methylene blue (MB) from aqueous solutions using sulfuric acid modified Cupressus semperirens cones (H₂SO₄-CSC), was investigated. Results showed that a pH value of 12 was favorable for the adsorption of MB and that the moisture and ash yields are suitable for industrial exploitation. A high porosity value was found, 68.1%. In agreement with its low content of basicity compared to its acidity, the H₂SO4-CSC absorbent had an acidic behavior. Rate constants of pseudo-first-order, pseudo-second-order, and nth kinetic model were determined to analyze the dynamic of the biosorption process; they showed that adsorption kinetics followed a pseudo-second-order and nth kinetic models. Ionic strength was shown to have a negative impact on the biosorption of MB onto H₂SO₄-CSC. The Sips isotherm model was found to be the most relevant to describe MB biosorption onto H₂SO₄-CSC with a correlation factor R²?>?0.999. The biosorption capacity of H₂SO₄-CSC was found to be 460?mg?g^?1 at 10°C and 590?mg?g^?1 at 25°C, confirming biosorbent efficiency for the removal of MB dye from aqueous solutions. Thermodynamic parameters indicated that the biosorption process of MB was endothermic and more effective at high temperatures. The values of ΔG° and ΔH° confirmed that the biosorption of MB onto H₂SO₄-CSC was spontaneous and endothermic in nature. An irregular increase in randomness at the H₂SO₄-CSC–solution interface during the biosorption process was suggested by the positive values of ΔS°.     

Fleece Production,Scouring Yield,and Down Hair Yield of Tunisian Dromedary

The results show that the greasy fleece weight varied from 0.3 kg to 2.42 kg with an average of 0.75 kg. The fleece weight decreases according to the animal age. In fact, the factor “age” has a significant effect on the dromedary fleece weight. Average scoured yield was 96% with V% of 1.6%. This indicated that matter loss, after scouring dromedary fibres, was lower than wool and cashmere. Scoured yield did not vary between samples of varied dromedary body areas in any age. The down hair yield for the fleece of the Tunisian dromedary varies between 34% and 61% with a mean of 45%. This raises interest when compared to the cashmere yield. There is a clearly decreased dromedary down hair yield according the factor “age”. The analysis of the variance shows that the dromedary down hair yield was affected by the factors “age” and body area of the animal.

Following this work it will be possible to predict the amount of down yield in the fleece of Tunisian dromedary knowing age. Consequently, it will be possible to estimate the total amount of textile material camel from dromedary located in Tunisia.     

Acoustically tunable wavelength filter with gain

The first integrated optical amplifying acoustically tunable wavelength filter in Er-doped LiNbO₃ is reported. At the signal wavelength of λ_s=1531 nm a maximum gain of 4.8 dB has been obtained with a coupled pump power of 160 mW (λ_p =1484 nm). Lossless signal transmittance has been achieved with a pump power as low as 13.5 mW for λ_s>1561 nm     

Substrate Temperature-Dependent Physical Properties of Thermally Evaporated Sn_4Sb_6S_(13)Thin Films

In this work,the homogenous thin films of sulfosalt Sn_4Sb_6S_(13) were successfully synthesized by the thermal evaporation technique onto corning 7059 glass substrates heated at various temperatures in the range of 30-200 ℃.The surface morphology and structural characteristics of Sn_4Sb_6S_(13) films were analyzed by atomic force microscopy,X-ray diffraction,and energy-dispersive X-ray,respectively.The X-ray diffraction analysis revealed that Sn_4Sb_6S_(13) thin films crystallized in monoclinic structure according to a preferential direction(6 11).An improvement in the structural properties by increasing the substrate temperature was observed.The values of some important parameters such as absorption coefficient(α),band gap(E_g),refractive index(n),extinction coefficient(k),and dielectric constant(ε_∞) of thin film were determined.The absorption coefficient was larger than 10~5 cm~(-1) in the visible range.The electron transition of Sn_4Sb_6S_(13)films was direct allowed with the values that decreased(2-1.69 eV) by increasing substrate temperature from 30 to 200 ℃.The dispersion data obeyed the single oscillator relation of the Wemple-DiDomenico model and Cauchy model.The electrical free carrier susceptibility and the carrier concentration of the effective mass ratio were estimated according to the model of Spitzer and Fan.     

Polarization-independent integrated optical, acoustically tunabledouble-stage wavelength filter in LiNbO3

We report a polarization-independent integrated acousto-optical double-stage wavelength filter in X-cut, Y-propagating LiNbO₃. The device consists of a combination of four acousto-optical mode converters, a TE- and a TM-pass polarizer, and two polarization splitters; their specific design and properties are discussed. The filter has a bandwidth of 1.4 nm and a tuning range of 76 nm around λ1.55 μm. Maximum filter transmission is achieved with a RF drive power of only 80 mW; it excites via a single unidirectional transducer a guided surface acoustic wave driving the four polarization converters of both stages. Fiber-to-fiber insertion loss is 4.6 dB for TM- and 4.8 dB for TE-polarized waves. Multiwavelength filtering has been demonstrated     

Optical and Optoelectronic Properties Enhancement of Porous Silicon Treated with Indium Oxide

This paper presents the results of the effect of Indium oxide (In2O3) on the structural, optical, and optoelectronic properties of porous silicon (PS). The results show an important improvement of optoelectronic property of PS coated with In2O3 as a antireflective thin film. The treated PS with In2O3 thin film was thermally annealed at various temperatures to improve the efficiency of the photovoltaic cells. The deposition of In2O3 onto the PS sample was performed by simple immersion method. Surface morphology and chemical composition modification of the samples In2O3/PS were analyzed by SEM, EDX, and FTIR spectroscopy. Total reflectivity of In2O3/PS layers decreases significantly compared to as-prepared PS owing to an improvement in the light absorption. The PS treated with In2O3 shows a significant enhancement in the minority carrier lifetime (τeff) indicating an improved surface quality in comparison with the untreated PS. Photoluminescence (PL) measurements of PS layer treated with In2O3 has revealed an increase in PL-intensity and a bleu shift in emission PL band as a function of annealing temperature. The PL and τeff enhancement are due to the surface passivation improvement and the decrease of recombination process.     

Integrated optical, wavelength selective, acoustically tunable2×2 switches (add-drop multiplexers) in LiNbO3

Fully packaged, polarization independent, integrated acoustooptic 2×2 switches have been developed which can be also used as add/drop multiplexers. The devices have been fabricated in X-cut Y-propagating LiNbO₃ and can be operated at wavelengths around 1550 nm. They consist of passive polarization splitters and acoustooptic TE-TM converters with weighted coupling. A filter bandwidth of 2.0 nm and a tuning range of 130 nm have been obtained. The fiber-to-fiber insertion loss is <4.6 dB and a residual polarization dependence of 1.3 dB for bar-state and 0.1 dB for cross-state routing has been achieved