Context-aware multimodal recommendations of multimedia data in cyber situational awareness

Multimedia Tools and Applications - The current proliferation of large amounts of multimedia data creates an unprecedented challenge for security analysts in the context of Cyber Situational...     

Mechanical,thermal and microstructural characteristics of cellulose fibre reinforced epoxy/organoclay nanocomposites

Epoxy nanocomposites reinforced with recycled cellulose fibres (RCFs) and organoclay platelets (30B) have been fabricated and investigated in terms of WAXS, TEM, mechanical properties and TGA. Results indicated that mechanical properties generally increased as a result of the addition of nanoclay into the epoxy matrix. The presence of RCF significantly enhanced flexural strength, fracture toughness, impact strength and impact toughness of the composites. However, the inclusion of 1 wt.% clay into RCF/epoxy composites considerably increased the impact strength and toughness. The presence of either nanoclay or RCF accelerated the thermal degradation of neat epoxy, but at high temperature, thermal stability was enhanced with increased char residue over neat resin. The failure micromechanisms and energy dissipative processes in these nanocomposites were discussed in terms of microstructural observations.     

Structural and optical properties of thermally evaporated 1,4,8,11,15,18,22,25-octahexylphthalocyanine thin films

Metal-free 1,4,8,11,15,18,22,25-octahexylphthalocyanine was prepared directly by the cyclotetramerization of 3,6-dihexylphthalonitrile using lithium butoxide in butanol. Thin films of the material were deposited on glass substrates by the thermal evaporation technique. The structure of the films was found to be in the form, and showed a strong peak indicating preferential orientation. The surface morphology of the thin films was investigated by atomic force microscopy and showed that the molecules of 1,4,8,11,15,18,22,25-octahexylphthalocyanine grow in stacks of parallel rows. The spectrophotometric measurements of transmittance and reflectance were carried out in the wavelength range 190–3000 nm. The refractive index, n, and absorption index, k, were found to be independent of annealing at 373 K. The B band absorption occurred at 356 nm, and the Q band showed a doublet at 667 and 739 nm. Other optical parameters, such as absorption coefficient and optical dielectric constant ε, were determined.     

Flexible Temperature-Invariant Polymer Dielectrics with Large Bandgap

Flexible dielectrics operable under simultaneous electric and thermal extremes are critical to advanced electronics for ultrahigh densities and/or harsh conditions. However, conventional high-performance polymer dielectrics generally have conjugated aromatic backbones, leading to limited bandgaps and hence high conduction loss and poor energy densities, especially at elevated temperatures. A polyoxafluoronorbornene is reported, which has a key design feature in that it is a polyolefin consisting of repeating units of fairly rigid fused bicyclic structures and alkenes separated by freely rotating single bonds, endowing it with a large bandgap of ≈5 eV and flexibility, while being temperature-invariantly stable over −160 to 160 °C. At 150 °C, the polyoxafluoronorbornene exhibits an electrical conductivity two orders of magnitude lower than the best commercial high-temperature polymers, and features an unprecedented discharged energy density of 5.7 J cm⁻³ far outperforming the best reported flexible dielectrics. The design strategy uncovered in this work reveals a hitherto unexplored space for the design of scalable and efficient polymer dielectrics for electrical power and electronic systems under concurrent harsh electrical and thermal conditions.     

CdS thin films growth by ammonia free chemical bath deposition technique

Cadmium Sulfide CdS thin films were deposited by chemical bath deposition technique using ethanolamine as complexing agent instead of commonly used ammonia to avoid its toxicity and volatility during film preparation. In order to investigate the film growth mechanism samples were prepared with different deposition times. A set of substrates were dropped in the same bath and each 30 minutes a sample is withdrawn from the bath, by this way all the obtained films were grown in the same condition. The films structure was analyzed by X rays diffraction. In early stage of growth the obtained films are amorphous, with increasing the deposition time, the films exhibits a pure hexagonal structure with (101) preferential orientation. The film surface morphology was studied by atomic force microscopy. From these observations we concluded that the early growth stage starts in the 3D Volmer-Weber mode, followed by a transition to the Stransky-Krastanov mode with increasing deposition time. The critical thickness of this transition is 120 nm. CdS quantum dots were formed at end of the film growth. The optical transmittance characterization in the UV-Visible range shows that the prepared films have a high transparency ranging from 60 to 80% for photons having wavelength greater than 600 nm.     

DL-HAR: Deep Learning-Based Human Activity Recognition Framework for Edge Computing

Human activity recognition is commonly used in several Internet of Things applications to recognize different contexts and respond to them. Deep learning has gained momentum for identifying activities through sensors, smartphones or even surveillance cameras. However, it is often difficult to train deep learning models on constrained IoT devices. The focus of this paper is to propose an alternative model by constructing a Deep Learning-based Human Activity Recognition framework for edge computing, which we call DL-HAR. The goal of this framework is to exploit the capabilities of cloud computing to train a deep learning model and deploy it on lesspowerful edge devices for recognition. The idea is to conduct the training of the model in the Cloud and distribute it to the edge nodes. We demonstrate how the DL-HAR can perform human activity recognition at the edge while improving efficiency and accuracy. In order to evaluate the proposed framework, we conducted a comprehensive set of experiments to validate the applicability of DL-HAR. Experimental results on the benchmark dataset show a significant increase in performance compared with the state-of-the-art models.     

A comparison of methods for assessing dough and gluten strength of durum wheat and their relationship to pasta cooking quality

The best rheological test to differentiate dough and gluten strength and predict cooking quality of different durum wheat cultivars is not recognised yet. Sixteen durum wheat cultivars were grown at three locations in North Dakota using a randomised complete block design to compare different methods for measuring dough/gluten strength and to relate their results to pasta cooking quality. Different rheological tests were used to distinguish the weak, medium strong, strong and very strong gluten cultivars. Alveograph, gluten index and glutograph were the only tests that could differentiate between medium strong and strong gluten samples. Alveograph was the best method to predict gluten strength where few samples are available for assessment. In comparison with alveograph, the gluten index was faster and required less semolina and gave similar results as the alveograph. All tests had significant correlation with cooked spaghetti firmness and negative correlation with cooked weight.     

Corundum nanostructure ITO film fabrication: An approach for physical properties assessment

Corundum (hexagonal) structure indium tin oxide (h-ITO) nanocrystals have been synthesized by subjecting an aqueous solution of In and Sn chlorides (Sn/In 8 wt.%) to a hydrothermal process followed by annealing at 450 °C in forming gas for 1 h. The annealing temperature was selected based on thermo-gravimetric analysis (TGA) and differential thermal analysis (DTA) of the dried precipitated powder, which showed a stable weight and phase at temperatures above 420 °C. X-ray diffraction (XRD) patterns showed the formation of orthorhombic InOOH precipitates that is transformed, after annealing, into h-ITO nanocrystals with 32 nm average crystal size. For nanostructure film deposition, dispersed sols of the prepared nanocrystals were spun coated on glass substrates. The films were densified by UV irradiation, whilst four-probe method was used to measure its sheet resistance. A sheet resistance as low as 10.6 kΩ □ have been reached. Scanning electron microscope (SEM) and high resolution transmission electron microscope (HRTEM) showed that the films have high surface roughness and nanopores. The transmittance spectra of the nanostructure films were measured in the UV–vis–NIR wavelength range. In addition to its low resistivity, nanostructure h-ITO films showed a wide range of transparency.     

High-fiber date pits pudding: formulation,processing, and textural properties

The aim of this project was to prepare high-fiber pudding using date pits to meet the FDA requirement for health claim. Pudding desert was prepared with dates pits (DP), starch, sugar, xanthan gum (DX), flaxseeds gum (DF), and powdered milk. DP were milled, sieved through 149-µm sieve, and used for formulating high-fiber pudding. The pudding formulation included yeast, DX, or DF, and without gum (DP). Danette chocolate pudding, a commercial sample, was used as a reference. The formulation was cooked using rapid visco analyzer (RVA), and the gel was further analyzed by Brookfield viscometer and texture analyzer. The RVA profile of the formulation included peak viscosity, setback, and final viscosity. The data obtained from the RVA showed that pudding samples containing DX or DF gums exhibited higher peak viscosities (3,012.7 ± 22.5, 1,236.3 ± 110.9 cP, respectively) as compared to the DP pudding 735.3 ± 38.3 cP. The presence of DX instigated higher gel hardness than DF and DP, whereas DF caused higher cohesiveness than DP and DX. The shear stress as a function of shear rate profile indicated that DF was closer to Danette pudding sample. The consistency coefficient index (K), which was obtained from the power law, was higher for both DX and DF, indicating higher viscosity, whereas lower flow behavior index (n) signifies a more pseudoplastic system of these samples. Based on the Ea values, it can be concluded that DX sample is less temperature dependent (lower Ea) than DF (higher Ea). The sensory testing showed that yeast treatment brought the formulation closer to the control in terms of panel acceptance.     

Link failure and congestion-aware reliable data delivery mechanism for mobile ad hoc networks

Link failures and packet drops due to congestion are two frequently occurring problems in mobile ad hoc networks, degrading the network performance significantly. In this paper, we propose a link failure and congestion-aware reliable data delivery (LCRDD) mechanism that jointly exploits local packet buffering and multilevel congestion detection and control approaches for increasing the data delivery performance. On the detection of link failure or congestive state, an LCRDD intermediate node buffers the incoming data packets at the transport layer queue and resumes transmission when the route is repaired locally. In addition, LCRDD’s multilevel congestion detection helps it to take the most appropriate action proactively. Thus, it offers increased reliability and throughput and decreased end-to-end packet delivery delay and routing overhead compared to state-of-the-art protocols, as shown in results of performance evaluations carried out in network simulator v-2.34.