Origin-Destination Matrix Estimation Problem in a Markov Chain Approach

Networks and Spatial Economics - In this paper, a Markov chain origin-destination matrix estimation problem is investigated in which the average time between two incoming streams to or outgoing...     

Relay selection based clustering techniques for high density LTE networks

Wireless Networks - In very crowded areas, a large number of LTE users contained in a single cell will try to access services at the same time causing high load on the Base Station (BS). Some users...     

Urban object extraction using Dempster Shafer feature-based image analysis from worldview-3 satellite imagery

A detailed and up-to-date land use of the urban environment is essentially required in many applications. Very high-resolution (VHR), Multispectral Scanner System (MSS) Worldview-3 (WV-3) satellite imagery provides detailed information on urban characteristics, which should be professionally mined. In this research, WV-3 was processed by machine learning (ML) methods to extract the most accurate urban features. Fuze-Go panchromatic sharpening in conjunction with atmospheric and topographic correction was initially utilized to increase the image quality and colour contrast. Three image analysis approaches including, current pixel-based image analysis (PBIA), object-based image analysis (OBIA) and new feature-based image analysis (FBIA) were implemented on WV-3 image. The k-nearest neighbour (k-NN), Naive Bayes (NB), support vector machine (SVM) classifiers were represented by PBIA, the Decision Tree (DT) classifier was examined as OBIA and the Dempster–Shafer (DS) fusion classifier was manifested for the first time as FBIA. In order to engage DS as FBIA, four types of Belief Masses, namely, Precision, Recall, Overall Accuracy, and kappa coefficient (?) were implemented and compared to assign the most likelihood urban features. All the applied classifiers were also trained on the first site and then tested on another site to examine the transferability. The accuracy, reliability, and computational time of all classifiers were examined by confusion matrix and McNemar assessment. Results show improvements on the detailed urban extraction obtained using the proposed FBIA with 92.2% overall accuracy in compared with PBIA and OBIA. The FBIA result of urban extraction is more consistent when transferred to another study area and consumes much lesser time than OBIA. Also, the precision mass belief measurement achieved highest efficiency regarding receiver operating characteristic (ROC) curve rate.     

One-pot functionalization of carbon nanotubes by WO3/MoO3 nanoparticles as oxidative desulfurization catalysts

Novel carbon nanotube hybrids with good catalytic properties can be obtained by a facile and fast method for immobilization of WO₃/MoO₃ on the surface and into the cavity of CNTs. We reported here a one-step wet chemical method for functionalization of MWNTs with tungsten and molybdenum oxides using oxodiperoxo complexes (WO₅/MoO₅) as precursors that can provide a novel methodology for future nanofabrication technology. The prepared WO₃/MoO₃-CNT hybrids were characterized by FTIR, XRD, SEM, TEM, and TGA analysis. It is suggested that the CNTs on treatment with WO₅ and MoO₅ complexes become functionalized and the end of the MWNTs was opened during the oxidation in the presence of peroxo groups. Then, WO₅/MoO₅ in the solution was adsorbed on the surface of CNT due to the coordination process. Finally, WO₃/MoO₃ nanoparticles are formed in-situ on the outer and inner surface of carbon nanotube during the treatment at 350?°C. WO₃/MoO₃ show a strong interaction with MWNTs and resulting WO₃/MoO₃-CNT hybrids were proven to be the good catalysts in oxidative desulfurization of the model fuel. The catalytic activity of the hybrid was found to increase when WO₃ react with functional group of CNTs. The best results (99.2%) have been obtained on the 2WO₃/MoO₃-CNT with the 16.5:8.5% wt. of WO₃:MoO₃.     

Isolation enhancement of rectangular dielectric resonator antennas using wideband double slit complementary split ring resonators

A wideband epsilon‐negative structure is employed as one‐layer and two‐layer isolators to reduce mutual coupling in multiple‐input multiple‐output systems composed of two E‐coupled rectangular dielectric resonator antennas. The proposed unit cell with ?15 dB bandwidth for S₂₁ extending from 1970 to 3317 MHz, is a double slit complementary split ring resonator etched on the ground plane of a stripline. Each layer is composed of a 2 × 3 array of the suggested unit cell. Reduction in isolation of more than 11 dB for the one‐layer case and higher than 20 dB for the two‐layer case are measured within the frequency range of 2.604 to 2.64 GHz which includes WiMAX. The highest isolation level of 36 dB is realized at 2.868 GHz. The impedance matching, gain, radiation efficiency, and envelope correlation are improved compared to the original case. A prototype is designed, fabricated, and tested. Simulation data and measurement results are in good agreement.     

Facile synthesis and characterization of Sc2O3 nanoparticles for electrocatalytic oxidation of ethanol: Cyclic voltammetry and chronoamperometry studies

In this research, scandium oxide, Sc₂O₃, nanoparticles (Sc₂O₃NPs) were synthesized via a facile and simple sol-gel auto-combustion process with olive oil as capping agent. Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), scanning electron microscopy (SEM) and UV–visible diffuse reflectance spectra (UV-DRS) were used to characterize the particle size, morphology and optical properties of the calcined powders. The XRD patterns showed that Sc₂O₃ nanoparticles have cubic structure with particle size about 8 nm. UV–vis spectroscopy showed a strong sharp absorption peak around 315 nm, attributed to the O_2p → Sc_3d charge-transfer interaction. In the next step, Sc₂O₃NPs were used for modification of carbon paste electrode (CPE) surface. Then, the electrocatalytic properties of the Sc₂O₃NPs/CPE towards ethanol oxidation were compared with the CPE. The results showed the electrocatalytic performance of the Sc₂O₃NPs/CPE is higher than the unmodified CPE. Also, chronoamperometry studies showed that Sc₂O₃/CPE has long-term stability against the poisoning species, as compared with the CPE. Therefore, Sc₂O₃ catalyst is proposed as an efficient anodic electrode for use in direct ethanol fuel cells in acidic media.     

Ultrasonic assisted synthesis of a nano-sized Co2SnO4/graphene: A potential material for electrochemical hydrogen storage application

A facile and rapid sonochemical method has been developed for the synthesis of Co₂SnO₄ nanostructures in presence of glucose as a green capping agent, for the first time. The effect of different parameters such as ultrasonic irradiation, time irradiation, basic agent and solvent were studied to reach optimum size and morphology conditions. The optimized Co₂SnO₄ nanostructures anchored onto graphene sheets and Co₂SnO₄/Graphene nanocomposite synthesized through pre-graphenization, successfully. In this paper, hydrogen storage capacity of optimized Co₂SnO₄ nanostructures and Co₂SnO₄/Graphene nanocomposite compared for the first time. Co₂SnO₄/Graphene nanocomposite show more excellent electrochemical performance than pure Co₂SnO₄ nanoparticles. It was found that the synergistic effect between Co₂SnO₄ nanoparticles and graphene sheets can improve the electrochemical performance of this hybrid composites electrode. After 25 cycles, the discharging capacities of the Co₂SnO₄ nanostructure and Co₂SnO₄/Graphene nanocomposite electrode reach 1190 and 2700 mAh/g, respectively.     

Is apelin gene expression and concentration affected by dietary intakes? A systematic review

Overproduction of apelin in obesity could be one of the last protective defenses before type 2 diabetes develops. To summarize the existing evidence on the association between dietary intake and apelin gene expression and concentration. We systematically searched MEDLINE, EMBASE, and google scholar and hand-searched bibliographies, including peer-reviewed articles with English abstracts, without restriction in publication date, updated until 21 February 2016 that reported the association between dietary intake and apelin gene expression or concentration. From a total of 1075 articles, we identified 12 relevant studies. There were 6 clinical trials in human and 6 studies in animals. Overall, two of three studies conducted in humans showed that calorie-restriction diet in obese subjects decreases apelin concentration. Five animal studies reported that higher intake of fatty acids and eicosapentaenoic acid (EPA) increased apelin expression and concentration. Given the paucity of data available, the heterogeneity of study designs used, and exposures tested, no quantitative meta-analysis was justified. Based on human studies, hypocaloric diet can reduce apelin concentration in obese individuals. In addition, higher intakes of total fatty acids and EPA may increase apelin gene expression and concentration.     

Pyramidal modeling of geometric distortions for retargeted image quality evaluation

Multimedia Tools and Applications - Content-aware retargeting methods are used to adjust images to different resolutions and aspect ratios with low deformation and information loss in salient...