Lexicon based semantic detection of sentiments using expected likelihood estimate smoothed odds ratio

Sentiment analysis is an active research area in today’s era due to the abundance of opinionated data present on online social networks. Semantic detection is a sub-category of sentiment analysis which deals with the identification of sentiment orientation in any text. Many sentiment applications rely on lexicons to supply features to a model. Various machine learning algorithms and sentiment lexicons have been proposed in research in order to improve sentiment categorization. Supervised machine learning algorithms and domain specific sentiment lexicons generally perform better as compared to the unsupervised or semi-supervised domain independent lexicon based approaches. The core hindrance in the application of supervised algorithms or domain specific sentiment lexicons is the unavailability of sentiment labeled training datasets for every domain. On the other hand, the performance of algorithms based on general purpose sentiment lexicons needs improvement. This research is focused on building a general purpose sentiment lexicon in a semi-supervised manner. The proposed lexicon defines word semantics based on Expected Likelihood Estimate Smoothed Odds Ratio that are then incorporated with supervised machine learning based model selection approach. A comprehensive performance comparison verifies the superiority of our proposed approach.     

Multidisciplinary Design and Optimization of Satellite Launch Vehicle Using Latin Hypercube Design of Experiments

The design of new Satellite Launch Vehicle (SLV) is of interest, especially when a combination of Solid and Liquid Propulsion is included. Proposed is a conceptual design and optimization technique for multistage Low Earth Orbit (LEO) bound SLV comprising of solid and liquid stages with the use of Genetic Algorithm (GA) as global optimizer. Convergence of GA is improved by introducing initial population based on the Design of Experiments (DOE) Technique. Latin Hypercube Sampling (LHS)-DOE is used for its go...     

A chaos-based image encryption algorithm based on multiresolution singular value decomposition and a symmetric attractor

ABSTRACT

This paper proposes a new image cryptosystem using multiple chaotic maps and multiresolution singular value decomposition (MR-SVD). The encryption process starts with implementing the MR-SVD to decompose the original image into the four fundamental sub-bands, i.e., Approximation (A), Vertical (V), Horizontal (H), Diagonal (D) sub-bands respectively. Since the approximation part gives the most information about the image, this sub-band is selected to perform permutation and diffusion. The permutation of all the four sub-bands is done by deploying the Baker map. The diffusion of pixels in the permuted approximation part is done by our neighbourhood diffusion scheme that uses the numerical solution of the chaotic Thomas' cyclically symmetric attractor. The final cipher is obtained by combining all the four (A, H, V, D) partial ciphers by performing inverse MR-SVD. The experimental results of our proposed scheme on various benchmarks tests indicate that the algorithm is highly secure and can withstand various attacks.     

Evaluation of mechanical properties and hydrophobicity of room-temperature,moisture-curable polysilazane coatings

Polysilazane coatings have a broad need in real-life applications, which require low processing or working temperature. In this work, five commercially available polysilazanes have been spin-coated on polycarbonate substrates and cured in ambient environment and temperature to obtain transparent, crack-free, and dense films. The degree of crosslinking is found to have a significant impact on the hardness and Young's modulus of the polysilazane films but has a minor influence on the film thickness and hydrophobicity. Among all five polysilazane coatings, the inorganic perhydropolysilazane-based coating exhibits the largest hardness (2.05 ± 0.01 GPa) and Young's modulus (10.76 ± 0.03 GPa) after 7 days of curing, while the polyorganosilazane-derived films exhibit higher hydrophobicity. The molecular structure of polysilazanes plays a key role in mechanical properties and hydrophobicity of the associated films, as well as the adhesion of coatings to substrates, providing an intuitive and reliable way for selecting a suitable polysilazane coating material for a specific application.     

VR and AR virtual welding for psychomotor skills: a systematic review

Multimedia Tools and Applications - Virtual reality (VR) and augmented reality (AR) continue to play an important role in vocational training in the current pandemic and Industrial Revolution 4.0...     

Understanding the charge transfer and defect states in ZnO/In2O3 composite nanostructures (CNs)

Journal of Materials Science: Materials in Electronics - This report presents the VLS synthesis and the study of the charge carrier transport through defect states across the interface in ZnO/In2O3...     

Tribological Testing of Hemispherical Titanium Pin Lubricated by Novel Palm Oil: Evaluating Anti-Wear and Anti-Friction Properties

In this study, the properties of hip implant material and lubricants were examined using a pin on disc apparatus, to compare the effect of metal-on-metal(Mo M)contact with a bio-lubricant derived from palm oil. The behaviour of the lubricants was observed during the experiments, in which a hemispherical pin was loaded against a rotating disc with a groove. A titanium alloy was used to modify the hemispherical pin and disc. Before and after the experiments, the weight and surface roughness were analysed, to detect any degradation. The results were compared according to the different kinematic viscosities.The wear rates and level of friction with each lubricant were also examined. The lubricant with the highest viscosity had the lowest frictional value. Therefore, developing suitable lubricants has the potential to prolong the lifespan of prostheses or implants used in biomedical applications. The experiments collectively show that lubricants derived from palm oil could be used as efficient bio-lubricants in the future.     

Analysis of exergetic performance for a solar air heater with metal foam fins

In this experimental study, an exergetic analysis is presented for solar air heaters (SAHs) that have absorber plates equipped with different fin arrangements. The following two types of fins were used: solid fins (conventional) and metal foam fins. Longitudinal, staggered, and corrugated fin arrangements in SAHs were investigated under the weather conditions experienced in Baghdad, Iraq in February to April 2018. The exergy efficiency and exergy loss of the SAHs were evaluated for five air mass flow rates ranging from 0.011 to 0.059 kg/s. Based on the exergy analysis, SAHs with metal foam fins are more efficient than those with solid fins. In addition, corrugated metal foam fins introduce more turbulent flow than the other fin configurations. It was found that the exergy loss and the exergy efficiency were directly proportional to the values of solar irradiance and air mass flow rates. At solar noon, the maximum values for exergy change were 127 and 89 W/m² for air mass flow rates of 0.011 and 0.059 kg/s, respectively.