An experimental evaluation of visual similarity for HDR images

In this paper, we investigate visual similarity for high dynamic range (HDR) images. We collect crowdsourcing data through a web-based experimental interface, in which the participants are asked to choose one of the two candidate images as being more similar to the query image. Triplets forming the query-and-candidates sets are obtained by random sampling from existing HDR data sets. Experimental control factors include choice of tone mapping operator (TMO), choice of distance metric, and choice of image feature. The image features that we experiment with are chosen from the features that are commonly used in the usual low dynamic range setting including features learned via Convolutional Neural Networks. The set of image features also includes combined features where the combination coefficients are estimated using logistic regression. We compute correlations between human judgments and quantitative features to understand how much each feature contributes to visual similarity. Combined features yield nearly 84% agreement with human judgments when applied on tone mapped images. Though we observed that using common features directly on raw or linearly scaled HDR images yield subpar correlation estimates compared to using them on tone mapped HDR images, we did not observe significant effect due to the choice of TMO on the estimates. As an application, we propose an improvement to style-based tone mapping for more correctly imparting desired styles to HDR images with different characteristics.

     

Excitation energy-dependent nature of Raman scattering spectrum in GaInNAs/GaAs quantum well structures

The excitation energy-dependent nature of Raman scattering spectrum, vibration, electronic or both, has been studied using different excitation sources on as-grown and annealed n- and p-type modulation-doped Ga_1 − xIn_xN_yAs_1 − y/GaAs quantum well structures. The samples were grown by molecular beam technique with different N concentrations (y = 0%, 0.9%, 1.2%, 1.7%) at the same In concentration of 32%. Micro-Raman measurements have been carried out using 532 and 758 nm lines of diode lasers, and the 1064 nm line of the Nd-YAG laser has been used for Fourier transform-Raman scattering measurements. Raman scattering measurements with different excitation sources have revealed that the excitation energy is the decisive mechanism on the nature of the Raman scattering spectrum. When the excitation energy is close to the electronic band gap energy of any constituent semiconductor materials in the sample, electronic transition dominates the spectrum, leading to a very broad peak. In the condition that the excitation energy is much higher than the band gap energy, only vibrational modes contribute to the Raman scattering spectrum of the samples. Line shapes of the Raman scattering spectrum with the 785 and 1064 nm lines of lasers have been observed to be very broad peaks, whose absolute peak energy values are in good agreement with the ones obtained from photoluminescence measurements. On the other hand, Raman scattering spectrum with the 532 nm line has exhibited only vibrational modes. As a complementary tool of Raman scattering measurements with the excitation source of 532 nm, which shows weak vibrational transitions, attenuated total reflectance infrared spectroscopy has been also carried out. The results exhibited that the nature of the Raman scattering spectrum is strongly excitation energy-dependent, and with suitable excitation energy, electronic and/or vibrational transitions can be investigated.     

The effect of Sn concentration on some physical properties of zinc oxide films prepared by ultrasonic spray pyrolysis

The effect of Sn concentration on zinc oxide (ZnO) film properties has been investigated by depositing films with various Sn concentrations in the solution (Sn/Sn + Zn ratio from 0 to 50 at%) at a substrate temperature of 350°C by ultrasonic spray pyrolysis (USP) technique. The deposited films were characterized for their electrical, structural, morphological and elemental properties using current-voltage and conductivity-temperature measurements, X-ray diffraction, scanning electron microscopy and energy dispersive X-ray spectroscopy. Electrical investigations showed that the resistivity of ZnO films decreases for lower Sn concentration (at 10%) and then increases for higher Sn concentration (at 30–50%). Also, depending on the increasing Sn concentration, energies of donor-like traps for ZnO films decreased and activation energy of donors for ZnO films increased. The XRD patterns showed that the as-deposited films have polycrystalline structure and the crystalline nature of the films was deteriorated with increasing Sn concentration and a shift to amorphous structure was seen. The effect of Sn concentration was to increase the surface roughening and change considerably the morphologies of ZnO films. The most homogenous surface was seen in ZnO films. EDS results showed that all elements in the starting solutions were in the solid films and Zn element is more dominant than Sn on the surfaces. After all investigations, it was determined that Sn incorporation dramatically modifies the properties of ZnO films. ZnO and ZnO:Sn (10 at%) films have a low resistivity and high transparency in the visible range and may be used as window material and antireflecting coating in solar cells while the other films may be used in gas sensors where high conductivity is unnecessary.     

Growth and Characterization of Zn-Incorporated Copper Oxide Films

In this work, undoped and Zn-doped copper oxide films were deposited on glass substrates at a substrate temperature of 250 ± 5°C by using an ultrasonic spray pyrolysis technique. Electrical, optical, and structural properties of the films were investigated, and the effect of Zn incorporation on these properties are presented. The variations of electrical conductivities and electrical conduction mechanisms of all films were investigated in the dark and in the light. Optical properties of the produced films were analyzed by transmission, linear absorption coefficient, and reflection spectra. The band gaps of the films were determined by an optical method. The film structures were studied by x-ray diffraction. To obtain information about structural properties in detail, the grain size (D), dislocation density (δ), and lattice parameters for preferential orientations were calculated. The elemental analyses were performed using energy-dispersive x-ray spectroscopy. It was concluded that Zn has a strong effect, especially on the electrical and structural properties, and the undoped and Zn-doped copper oxide (at 3%) films may be used as absorbing layers in solar cells due to their low resistivities and suitable linear absorption coefficient values.     

Characterization of chemically sprayed CdO films on borate and phosphate glass substrates produced by melt-quenching technique

The properties of substrates used to deposit thin films are an important parameter in thin film production. Instead of using a commercial substrate, in this work, borate and phosphate glasses have been obtained by classic melt-quenching technique to be used as substrates for CdO films. Also, a microscope glass substrate has been used to compare the coating properties by other glass substrates. All films have been produced by Ultrasonic Spray Pyrolysis technique. The substrate temperature has been selected as 275 ± 5 °C. Thicknesses and some optical parameters such as refractive index and extinction coefficient have been determined by spectroscopic ellipsometry. Absorbance and transmittance spectra have been taken by UV/VIS spectrophotometer. Four-probe method has been used to determine the electrical resistivity values of the films. XRD investigations have shown that type of the substrate dramatically affects the characteristics of CdO films. CdO film deposited on phosphate glass substrate has the best structural quality. Atomic Force Microscope has been used to investigate the surface properties and roughness values of the films.     

Some physical properties of copper oxide films: The effect of substrate temperature

In this work, copper oxide films were deposited at different substrate temperatures of 200, 250, 300 and 350 ± 5 °C by ultrasonic spray pyrolysis technique and the effect of substrate temperature on the structural, surface, optical and electrical properties of the films was presented. The film structures were studied by X-ray diffraction (XRD). To obtain information about structural properties in detail, the grain size (D), dislocation density (δ) and lattice parameters (a = b = c for cubic structure) for preferential orientations were calculated. The surface properties and elemental analyses were characterised using scanning electron microscopy and energy dispersive X-ray spectroscopy, respectively. Optical properties of the films were analyzed by transmission, linear absorption coefficient and reflection spectra, and the optical method was used to determine the band gaps of the films. The current–voltage values were measured with two-probe technique, and the electrical conductivities were calculated. Consequently, it was determined that substrate temperature has a strong effect on the structural, surface, optical and electrical properties of copper oxide films.     

Development of the TIGRE Compton telescope for intermediate-energy gamma-ray astronomy

Gamma-ray observations in the low and medium energy range (0.1-100 MeV) with sufficiently sensitive telescopes will provide unique insights into many outstanding high-energy astrophysics questions. The University of California, Riverside (UCR) Tracking and Imaging Gamma-Ray Telescope (TIGRE) Compton gamma-ray telescope uses multilayers of silicon strip detectors to, for the first time, track the Compton electron and CsI(Tl)-photodiode detectors to measure the scattered photon energy. By combining the Compton telescope's inherent imaging capability with improved background discrimination, a larger field-of-view and improved spectral and spatial resolutions, a significant improvement in sensitivity over Compton Gamma-Ray Observatory (CGRO) and INTEGRAL can be achieved. The well-type calorimeter design also enhances the instrument as a gamma-ray polarimeter. The development and flight of a robust Compton telescope represents a unique opportunity to continue the momentum of recent discoveries in low and medium energy gamma-ray astrophysics with CGRO and an absolutely essential step to an extended satellite mission by 2010.     

Requirements for forming an ‘e-supply chain’

In today's digital economy, web-based integration of the enterprises to form an e-supply chain is a critical weapon for orchestrating the whole supply chain towards competitiveness. This paper intends to discuss the requirements for forming an e-supply chain from different perspectives, such as integration with the legacy systems, timing and prior presence of ERP (enterprise resources planning) systems, BPR (business process re-engineering) needs of internal and external business processes and business intelligence/decision support needs. A look at technical knowledge and structure to construct an e-supply chain is provided. Challenges involved in forming an e-supply chain are also briefly mentioned as a separate section in this paper. During the study, requirements are gathered by making a review of recent literature.     

Effects of Packaging Materials and Filling Methods on Selected Characteristics of Otlu (Herby) Cheese

In this research, two kinds of filling methods (block and pieced) in two container types (pot and plastic) were used for the preparation of Otlu cheeses. The uses of different containers influenced (P < 0.01) acidity, pH, dry matter, fat contents and water soluble nitrogen. Degradation of α?s₁- and β-casein were higher in pieced cheeses in pot (P1F2). Also, breakdown products of casein were higher in P1F2 cheeses compared to others. The amounts of α?s₁- and β-caseins of all treatments decreased during ripening, while the amounts of α?s₁-I casein and breakdown products increased. The acceptability of cheeses in block form was higher.