Variations in normal color vision. IV. Binary hues and hue scaling

We used hue cancellation and focal naming to compare individual differences in stimuli selected for unique hues (e.g., pure blue or green) and binary hues (e.g., blue-green). Standard models assume that binary hues depend on the component responses of red-green and blue-yellow processes. However, variance was comparable for unique and binary hues, and settings across categories showed little correlation. Thus, the choices for the binary mixtures are poorly predicted by the unique hue settings. Hue scaling was used to compare individual differences both within and between categories. Ratings for distant stimuli were again independent, while neighboring stimuli covaried and revealed clusters near the poles of the LvsM and SvsLM cardinal axes. While individual differences were large, mean focal choices for red, blue-green, yellow-green, and (to a lesser extent) purple fall near the cardinal axes, such that the cardinal axes roughly delineate the boundaries for blue vs. green and yellow vs. green categories. This suggests a weak tie between the cone-opponent axes and the structure of color appearance.     

Enhancement of hydrogen storage properties of Ca3CH antiperovskite compound with hydrogen doping

The doping effect of hydrogen on the Ca₃CH_x (x = 1, 4, 7, 9, and 10) antiperovskite compounds has been examined using density functional theory (DFT). The results of the structural optimizations show that all these compounds have negative formation energy implying the energetic stability and synthesizability. The band structures that are essential for the electronic properties have been determined along with the partial density of states (DOS) showing the metallic behavior of these compounds. In addition, the electron-density distribution has been determined, and the charge of each ion in the structures has been obtained with the Bader partial charge analysis. Moreover, the electronic stability of these compounds has been determined using the band filling theory and the number of the electrons at the Fermi level. The results of the formation enthalpy and the electronic stability investigations imply that the most stable structure is Ca₃CH among the considered compounds. Ca₃CH₁₀ has the gravimetric storage capacity as 7.10 wt% that is the largest capacity among the considered compounds. Also, Ca₃CH₉ has the smallest hydrogen desorption temperature as 468.4 K among the studied compounds.     

Structural and Spectroscopic Properties of δ‐Y2Si2O7 Nanopowders Activated with Nd3+ Ions

Phosphors of δ‐Y₂Si₂O₇ doped with Nd³⁺ ions were prepared in the SiO₂–Y₂O₃ binary systems using the solgel technique. Nano‐sized crystalline phosphor powders were obtained by annealing the dried gels at 1480°C. The average grain sizes of the NYS1, NYS2, NYS3, and NYS4, powders were estimated to be 44.1, 41.3, 48.1, and 53.2 nm from the grain size distribution curves, respectively, and these results were confirmed by transmission electron microscope measurements. The spectroscopic properties of the powders were studied by measuring the luminescence spectra, and the decay curves of the ⁴F_3/2 emission level were measured at room temperature.     

On coverage issues in directional sensor networks: A survey

The coverage optimization problem has been examined thoroughly for omni-directional sensor networks in the past decades. However, the coverage problem in directional sensor networks (DSN) has newly taken attraction, especially with the increasing number of wireless multimedia sensor network (WMSN) applications. Directional sensor nodes equipped with ultrasound, infrared, and video sensors differ from traditional omni-directional sensor nodes with their unique characteristics, such as angle of view, working direction, and line of sight (LoS) properties. Therefore, DSN applications require specific solutions and techniques for coverage enhancement. In this survey article, we mainly aim at categorizing available coverage optimization solutions and survey their problem definitions, assumptions, contributions, complexities and performance results. We categorize available studies about coverage enhancement into four categories. Target-based coverage enhancement, area-based coverage enhancement, coverage enhancement with guaranteed connectivity, and network lifetime prolonging. We define sensing models, design issues and challenges for directional sensor networks and describe their (dis)similarities to omni-directional sensor networks. We also give some information on the physical capabilities of directional sensors available on the market. Moreover, we specify the (dis)advantages of motility and mobility in terms of the coverage and network lifetime of DSNs.     

Polymeric Side Chain Thioxanthone Photoinitiator for Free Radical Polymerization

Summary Side chain thioxanthone-containing polymer (PSt-TX) was synthesized and characterized by modification of polystyrene prepared by Atom Transfer Radical Polymerization. PSt-TX exhibits absorption characteristics similar to that of the unsubstitued thioxanthone. Its capability to act as initiator for the polymerization of methyl methacrylate was also examined.     

Heterogeneous catalytic degradation of cyanide using copper-impregnated pumice and hydrogen peroxide

The main objective of this research was to investigate the oxidative destruction of free cyanide with hydrogen peroxide and copper-impregnated pumice as a heterogeneous catalyst. Original or copper-impregnated pumices added alone were not effective adsorbents of negatively charged cyanide ions due to incompatible surface interactions. Peroxide and original pumices added together were also ineffective in removing cyanide. However, for all of the three natural pumices tested with various particle size fractions, the use of copper-impregnated pumices and peroxide together significantly enhanced both the initial rate and extent of cyanide removal. Although copper-impregnated specific surface area was the major factor affecting the rate and extent of cyanide destruction for a particular pumice source with similar surface chemistries, the type of surface chemistry (i.e., specific functional groups) within different pumice sources also appears to be a very important factor. Lower rates and extents of cyanide removals were observed at pH 11 compared to pH 8 probably because of the negative impacts of alkaline conditions in terms of scavenging peroxide and forming more negatively charged pumice surfaces. Both the initial rate and ultimate extent of cyanide removals were generally higher at a temperature of 20 degrees C compared with those found at 10 degrees C. The use of copper-impregnated pumice as a light, cheap, readily available, natural, and porous heterogeneous catalyst either in completely mixed/suspended or fixed-bed reactor configurations may be an effective treatment technology for cyanide removal from solution. This new approach may minimize downstream metal removal problems experienced in conventional cyanide oxidation technologies.     

Copper oxide- and copper-modified antibacterial ceramic surfaces

In the present study, copper oxide (CuO) and copper (Cu) particles were characterized and investigated to observe the effects of antimicrobial activity on ceramic tile surfaces. Scanning electron microscopy (SEM) and X-ray diffraction (XRD) techniques were used for particle characterization. A new formulation of antimicrobial glaze was achieved by the combination of two glaze compositions with different Cu and CuO content to obtain micro–nano hybrid surface morphology to provide the antibacterial property. Surface morphology of coated ceramic surfaces was examined by SEM in detail and water contact angles were measured with goniometer. The relationships between antibacterial effect, phase evolution, surface topography, and wettability of surfaces were determined. The tenorite phase of CuO was observed on both Cu- and CuO-modified surfaces. Both Cu and CuO particles in glazed ceramic surfaces showed the similar antibacterial activity against Staphylococcus aureus and Escherichia coli. The antibacterial activity was dependent on mainly tenorite phase crystallization. The amount of the tenorite phase that was slightly higher in the case of Cu-incorporated surfaces instead of CuO and hence the bactericidal effect was slightly more pronounced. Although the developed surfaces are not hydrophobic, they show antibacterial properties.     

Real time selection of scheduling rules and knowledge extraction via dynamically controlled data mining

A new scheduling system for selecting dispatching rules in real time is developed by combining the techniques of simulation, data mining, and statistical process control charts. The proposed scheduling system extracts knowledge from data coming from the manufacturing environment by constructing a decision tree, and selects a dispatching rule from the tree for each scheduling period. In addition, the system utilises the process control charts to monitor the performance of the decision tree and dynamically updates this decision tree whenever the manufacturing conditions change. This gives the proposed system the ability to adapt itself to changes in the manufacturing environment and improve the quality of its decisions. We implement the proposed system on a job shop problem, with the objective of minimising average tardiness, to evaluate its performance. Simulation results indicate that the performance of the proposed system is considerably better than other simulation-based single-pass and multi-pass scheduling algorithms available in the literature. We also illustrate knowledge extraction by presenting a sample decision tree from our experiments.     

Influence of Micro- and Nanonatural Fillers on Mechanical and Physical Properties of Foamed SMA Composites

This study is to investigate the reinforcing effects of fillers on mechanical and physical properties of foamed styrene-maleic anhydride (SMA) composites. According to the results, the best foaming was determined for starch reinforced SMA composite. The best result of expansion ratio was found as 22.75% to SMA/starch composites. Stereo light microscopy results demonstrated that the foamed cell distribution is heterogeneous and composed of two sections. The minimum density was found as 0.64 g/cm³ for foamed SMA/starch composites. Mechanical properties of all foamed composites were found to be low as compared to neat SMA composite.     

The evaluation of procedures for dyeing silk with buckthorn and walloon oak on the basis of colour changes and fastness characteristics

In this study, silk fabric samples were dyed according to various procedures with buckthorn (Rhamnus petiolaris Boiss) and walloon oak (Quercus ithaburensis Decaisne) extracts. Reversed‐phase high‐performance liquid chromatography with diode‐array detection was utilised for the identification of dyes present in the dyed silk fabrics and the plant extracts. The extraction of dyes was carried out with a hydrochloric acid/methanol/water (2:1:1; v/v/v) mixture. The colour coordinates of the silk fabrics were measured, and the rubbing, wash and light fastness properties of the dyed silk materials were determined and are discussed.