Optimal weighed Holoentropy for video compression: an advanced HEVC

ABSTRACT

In recent times, the applications of multimedia are rising in a greedy mode and hence the amount of video transactions is also increasing exponentially. This has shouted great demands on effective models on video encoding and also for reducing the transmission channel congestion. This research work introduces a managing technique termed weighted encoding for High-Efficiency Video Coding (HEVC). HEVC, also termed as MPEG-H Part 2 and H.265 is a video compression standard that is widely utilized AVC (H.264 or MPEG-4 Part 10). When compared to AVC, HEVC grants double the ratio of data compression at a similar level of quality of the video or considerably enhanced video quality at a similar bit rate. This work intends to optimize the weight that adopted in HEVC for encoding. For this, this paper proposes a new Iterative based propagation update in the water wave Optimization Algorithm (IPU-WWO), which is the improved form of Water wave Optimization (WWO). The performance of proposed IPU-WWO is compared over other conventional methods like Artificial Bee Colony (ABC), Firefly (FF), Particle Swarm Optimization (PSO) and Genetic Algorithm (GA) with respect to Peak Signal to Noise Ratio (PSNR). By doing the encoding process, it minimizes the video size with perceptually better quality video or PSNR.     

Scalable satisfiability checking and test data generation from modeling diagrams

We explore the automatic generation of test data that respect constraints expressed in the Object-Role Modeling (ORM) language. ORM is a popular conceptual modeling language, primarily targeting database applications, with significant uses in practice. The general problem of even checking whether an ORM diagram is satisfiable is quite hard: restricted forms are easily NP-hard and the problem is undecidable for some expressive formulations of ORM. Brute-force mapping to input for constraint and SAT solvers does not scale: state-of-the-art solvers fail to find data to satisfy uniqueness and mandatory constraints in realistic time even for small examples. We instead define a restricted subset of ORM that allows efficient reasoning yet contains most constraints overwhelmingly used in practice. We show that the problem of deciding whether these constraints are consistent (i.e., whether we can generate appropriate test data) is solvable in polynomial time, and we produce a highly efficient (interactive speed) checker. Additionally, we analyze over 160 ORM diagrams that capture data models from industrial practice and demonstrate that our subset of ORM is expressive enough to handle their vast majority.     

The mechanical behaviour of coal with respect to CO2 sequestration in deep coal seams

Carbon dioxide displays a strong affinity for coal due to its propensity to adsorb to the coal surface. The process of CO₂ adsorption on coal causes lowering of surface energy and, it is hypothesised that an associated decrease in surface film confinement results in a decrease in material tensile resistance. Following the results of work carried out on the mechanical influence of CO₂ on brown coal under in situ conditions [Viete DR, Ranjith PG. The effect of CO₂ on the geomechanical and permeability behaviour of brown coal: implications for coal seam CO₂ sequestration. Int J Coal Geol 2006;66(3):204–16], a theoretical explanation is proposed for the perceived lack of a weakening effect with the adsorption of CO₂ to coal at significant confining pressures. We propose that at significant hydrostatic stresses, resistance to failure is otherwise provided (by external confinement) and the effects of adsorptive weakening are concealed. Our model predicts that adsorptive weakening, fracturing under in situ stresses, and associated permeability increases are not an issue for coal seam CO₂ sequestration for sufficiently deep target seams. Lowering of the elastic modulus of coal upon introduction of CO₂ may proceed by means other than surface energy lowering and could well occur irrespective of the depth of sequestration. The effect of elastic modulus lowering under in situ conditions would be beneficial for the long-term retention of sequestered gases.     

An optimal weighted HEVC coding for video compression

Multimedia Tools and Applications - In recent years, the applications of multimedia are rising in greedy mode and hence the amount of video transactions are also increasing exponentially. It has...     

Angular absorptance and thermal degradation analysis of TiB2/Ti(B,N)/SiON/SiO2 multilayer solar absorber coating

Multilayer solar selective absorber coatings have been developed in the last few decades. The thermal stability in terms of microstructure gives an insightful understanding of the optical properties of such coatings. In this context, we extensively utilized transmission electron microscopy (TEM) analysis to establish the thermal stability of TiB₂/Ti(B,N)/SiON/SiO₂ coating, under thermal cycling/continuous heating to 500°C in vacuum for 250 h. In particular, this work reports the variation in the solar absorptance of TiB₂/Ti(B,N)/SiON/SiO₂ coating with different angles of incidence of the solar radiation. Extensive analysis using the TEM technique reveals the presence of oxide interlayers that act as diffusion barrier layers to enhance the thermal stability of the coating. Computational simulation using SCOUT software validates the measured reflectance spectrum of the developed multilayer coating. The minor changes in absorptance and emissivity after heat treatment in vacuum at 500°C, together with high solar absorptance over a broad angular variation, establish the potential application of TiB₂/Ti(B,N)/SiON/SiO₂ as a selective coating in concentrated solar power systems.     

Use of Digital Terrestrial Photogrammetry in rocky slope stability analysis by Distinct Elements Numerical Methods

Current approaches to rocky slope stability analysis require knowledge of the geometrical–structural setting, as well as the physical–mechanical properties of the intact material and its discontinuities. The physical–mechanical properties are derived from in situ and laboratory tests, whereas the geometrical characteristics come from field attitude measurements. Frequently, the inaccessibility of walls does not allow direct measurement of discontinuity surfaces by traditional geological methods. In such cases, data can only be obtained by statistical methods. Although this approach is significant and provides spatial meaning, it is ineffective for deterministic analysis.This paper provides a solution to this problem by applying digital terrestrial photogrammetric techniques employing a reamed bar, an aerostatic balloon and a helicopter. Results demonstrate that the accuracy and the quantity of geometrical and engineering–geological data coming from the photogrammetric survey, allow for numerical simulation of the relationship between rock elements as a function of their physical–mechanical properties and load conditions. The 3DEC code was chosen among the different methods available to model the discontinuous media through distinct elements.The proposed methodology was applied to a quarry located in the Carrara Marble District (the Apuan Alps, Italy), the largest and most exploited mining region in Europe. The economic value of the area required a detailed study of the presence of instability phenomena so that marble extraction could continue in safe conditions.     

A comparative study of generalized regression neural network approach and adaptive neuro-fuzzy inference systems for prediction of unconfined compressive strength of rocks

The engineering properties of rocks play a significant role in planning and designing of mining and civil engineering projects. A laboratory database of mechanical and engineering properties of rocks is always required for site characterization and mineral exploitation. Due to discontinuous and variable nature of rock masses, it is difficult to obtain all physicomechanical properties of rocks precisely. Prediction of unconfined compressive strength from seismic wave velocities (Compressional wave, Shear wave) and density of rock using generalized regression neural network (GRNN) and adaptive neuro-fuzzy inference systems (ANFIS) can be appropriate and alternate methods to minimize the time and cost of tests. GRNN and ANFIS models were trained with 41 data sets using conjugate gradient descent algorithms and hybrid learning algorithm, respectively. Performance of both the models was examined with 15 testing data sets. In the present study, obtained network performance indices such as correlation coefficient, mean absolute percentage error, root mean square error and variance account for indicate high performance of predictive capability of GRNN system and closer to actual data over the ANFIS.     

Experimental exploration of damage propagation in rocks using acoustic emission

Bulletin of Engineering Geology and the Environment - The formation of geological disasters, such as earthquakes and rock bursts, is a process similar to avalanches. These sudden disasters are...     

The effect of CO2 saturation on mechanical properties of Australian black coal using acoustic emission

Acoustic emission (AE) methods are now widely used for damage evaluation. For a better understanding of the damage mechanics of materials such as rocks, AE has been used to monitor stresses which induce crack closure, crack initiation and crack damage. In the present study, an AE system was used to study the damage behaviour of some Australian black coal samples subjected to uniaxial compression. Several samples were left in a container filled with 100% carbon dioxide (CO₂) at a certain pressure for 72 h prior to testing. The results were compared with samples which had only been exposed to the atmosphere to see if CO₂ had any adverse effect on the strength of coal. Strain gauges were installed on the samples and the measured axial and volumetric strains were studied in conjunction with the AE counts.The AE method was successfully used for detecting the onset of crack initiation and the crack damage stress threshold of the black coal samples. Of the coal samples examined, crack initiation and crack closure of the samples subjected to saturation with CO₂ occurred at stress corresponding to a higher percentage of the peak strength when compared to the samples which had only been exposed to atmospheric conditions. However, crack damage occurred at a higher percentage of peak strength and the average peak strength showed a higher value for samples in atmospheric condition when compared to CO₂ saturated samples. The results show that sorption of CO₂ can cause a reduction in strength of the black coal samples when tested under uniaxial compression. As the coal samples were highly inhomogeneous more tests are required in order to be able to confirm whether the adsorption of CO₂ will cause strength reduction in coal and to identify the actual underlying mechanisms.     

Pt-MoOx-carbon nanotube redox couple based electrocatalyst as a potential partner with polybenzimidazole membrane for high temperature Polymer Electrolyte Membrane Fuel Cell applications

A redox couple based electrocatalyst comprising of Pt-Multi Wall Carbon NanoTube (Pt-MWCNT) promoted with molybdenum oxide (MoO_x, 2 < x < 3) nanoparticles was prepared. The objective was to effectively organize the Pt-MoO_x interface on the smooth MWCNT surface to overcome the practical difficulties associated with establishing such interface with Pt dispersed on carbon morphologies possessing surface irregularities. The present study revealed the importance of stringent controlling of the additive level for maintaining a balanced bifunctional behavior of the catalyst combination through the synergistic effects by the components and the need of a proton conducting membrane operable at high temperature to get better output from the Polymer Electrolyte Membrane Fuel Cell (PEMFC) systems. An indigenously developed polybenzimidazole (PBI) membrane was used to fabricate a membrane electrode assembly (MEA) as it can be operated at higher temperatures compared to that of Nafion membranes. MoO_x additive level was carefully controlled by monitoring the active Pt area by cyclic voltammetry. All prepared electrocatalysts were characterized by using HRTEM, XRD and XPS to get information on dispersion and morphology, crystalinity and oxidation state of different elements, respectively. The system prepared with 5% MoO_x addition with respect to Pt (hereafter Pt-MoO_x(5%)-MWCNT) displayed balanced active Pt area and excellent oxygen reduction reaction (ORR) and methanol oxidation reaction (MOR) activities. Rotating Disk Electrode (RDE) system was extensively utilized to understand the ORR kinetics and the favorable role of MoO_x as the promoter in the reaction. The kinetic current (j_k) measured at 0.02 V vs. Hg/Hg₂SO₄ electrode from the Koutecky-Levich plots was 9 times higher and the apparent activation energy during single cell evaluation was 27 kJ/mol lower for the MoO_x promoted system, compared to the system without the additive. A higher operating temperature significantly favored the cell performance by a combined effect of enhancement in proton conductivity of the PBI membrane and possible kinetic benefit by the well postulated oxygen spill over effect by the MoO_x type systems in some combinations involving such systems.