Mixed convection dissipative viscous fluid flow over a rotating cone by way of variable viscosity and thermal conductivity

AbstractThe effects of temperature-dependent viscosity and thermal conductivity on the flow and heat transfer characteristics of a viscous fluid over a rotating vertical cone are premeditated. The properties of the fluid are assumed to be constant except for the density difference with the temperature. Also, the effect of viscous dissipation is considered in the energy equation. The highly nonlinear unsteady equations are converted into a system of nonlinear ordinary differential equations which is solved by using Homotopy analysis method. The interesting findings for different pertinent parameters on momentum, energy, skin friction coefficient and local Nusselt number are demonstrated in the form of graphs and tables. A comparison has been made with literature as a limiting case of the well-chosen unsteady problem

Task 1 Final Report, Theoretical/Mathematical Modeling of Ultrasonic Wave Propagation in Anisotropic Polycrystalline Stainless Steels

One of the tasks of the U.S. Nuclear Regulatory Commission-sponsored project titled "Reliability of Nondestructive Examination (NDE) for Nuclear Power Plant (NPP) Inservice Examination (ISI)" is to provide collaborative assistance to Commissariat à l’Energie Atomique (CEA) in France through theoretical predictions of ultrasonic scattering by grains of cast stainless steels (CASS) components. More specifically, a mathematical treatment of ultrasonic scattering in media having duplex micro¬structure is sought because cast stainless steel components often contains larger-scale macrograins that are composed of sub-grains/colonies. In this report, we present formal mathematical theories for ultrasonic wave propagation in polycrystalline aggregates having both simple (composed of grains only) and complex microstructures (having macrograins and sub-grains/colonies). Computations based on these theories are then carried out for ultrasonic backscatter power, attenuation due to scattering, and phase velocity dispersions. Specifically, numerical results are presented for backscatter coefficient for plane longitudinal wave propagating in duplex steel containing macrograins and colonies. Furthermore, the expected propagation characteristics (attenuation coefficient and phase velocity) are computed and described in this report for plane longitudinal waves propagating in (1) steels composed of randomly oriented grains, (2) [001] aligned grains encountered in austenitic stainless steel welds and casts, and (3) duplex steels

Substation system simulation models for transformer risk assessment analysis

This paper comprises a study which is carried out to investigate and evaluate the effect of lightning stresses on the 132 kV substation in the way to improve its reliability in the event of active lightning activities. The paper also detailed the modelling parameters of substation for this transient analysis in order to evaluate the performance and to recommend such configuration to optimize its design to be not only to withstand the stresses but to be more cost effective. The modelling and simulation are carried out using one of the most powerful power system simulations tools that is PSCAD-EMTDC and the substation layout design is adapted from 132/11 kV Simpang Renggam -- Ayer Hitam substation, courtesy of TNB. The model is based on single phase line model as it was suggested by the IEEE to be adequate to represent the substation in transient analysis simulation. The outcome of this paper would be the results of lightning stresses in term of voltage level measured at particular points in substation. The results are then compared with the suggested BIL for assessment of transformer failure

Leadership styles and generational effects: examples of US companies in Vietnam

Leadership styles are an important issue for a range of areas, including business and management. One aspect of this is the influence of the age of people on their receptivity to leadership styles. Yet, research on this area using Asian contexts is limited. Consequently, our research looks at the generational effect in the reception of leadership styles – performance-oriented and participative. In particular, we examine the different value orientations of age cohorts and their reception to different leadership styles in Vietnam. First, we outline three strands of literature, namely culture and leadership, generation as a subculture and Vietnam as a context for the transfer of leadership styles. Second, our research methodology is detailed. Third, our empirical research using case study methods is presented. Our results cover the characteristics of three main age cohorts: the resilience of the pre-1975 born, the adaptability of 1975–1986 born and the arrival of the post-1986 born. Following the discussion and implications, we provide some brief conclusions

Breast cancer image classification using pattern-based Hyper Conceptual Sampling method

The increase in biomedical data has given rise to the need for developing data sampling techniques. With the emergence of big data and the rise of popularity of data science, sampling or reduction techniques have been assistive to significantly hasten the data analytics process. Intuitively, without sampling techniques, it would be difficult to efficiently extract useful patterns from a large dataset. However, by using sampling techniques, data analysis can effectively be performed on huge datasets, to produce a relatively small portion of data, which extracts the most representative objects from the original dataset. However, to reach effective conclusions and predictions, the samples should preserve the data behavior. In this paper, we propose a unique data sampling technique which exploits the notion of formal concept analysis. Machine learning experiments are performed on the resulting sample to evaluate quality, and the performance of our method is compared with another sampling technique proposed in the literature. The results demonstrate the effectiveness and competitiveness of the proposed approach in terms of sample size and quality, as determined by accuracy and the F1-measure. 2018This contribution was made possible by NPRP-07-794-1-145 grant from the Qatar National Research Fund (a member of Qatar foundation). The statements made herein are solely the responsibility of the authors.Scopu

Cannabinoid Receptor 2 Agonist JWH-015 Inhibits Interleukin-1β-Induced Inflammation in Rheumatoid Arthritis Synovial Fibroblasts and in Adjuvant Induced Arthritis Rat via Glucocorticoid Receptor

Management of pain in the treatment of rheumatoid arthritis (RA) is a priority that is not fully addressed by the conventional therapies. In the present study, we evaluated the efficacy of cannabinoid receptor 2 (CB2) agonist JWH-015 using RA synovial fibroblasts (RASFs) obtained from patients diagnosed with RA and in a rat adjuvant-induced arthritis (AIA) model of RA. Pretreatment of human RASFs with JWH-015 (10–20 μM) markedly inhibited the ability of pro-inflammatory cytokine interleukin-1β (IL-1β) to induce production of IL-6 and IL-8 and cellular expression of inflammatory cyclooxygenase-2 (COX-2). JWH-015 was effective in reducing IL-1β-induced phosphorylation of TAK1 (Thr184/187) and JNK/SAPK in human RASFs. While the knockdown of CB2 in RASFs using siRNA method reduced IL-1β-induced inflammation, JWH-015 was still effective in eliciting its anti-inflammatory effects despite the absence of CB2, suggesting the role of non-canonical or an off-target receptor. Computational studies using molecular docking and molecular dynamics simulations showed that JWH-105 favorably binds to glucocorticoid receptor (GR) with the binding pose and interactions similar to its well-known ligand dexamethasone. Furthermore, knockdown of GR using siRNA abrogated JWH-015's ability to reduce IL-1β-induced IL-6 and IL-8 production. In vivo, administration of JWH-015 (5 mg/kg, daily i.p. for 7 days at the onset of arthritis) significantly ameliorated AIA in rats. Pain assessment studies using von Frey method showed a marked antinociception in AIA rats treated with JWH-015. In addition, JWH-015 treatment inhibited bone destruction as evident from micro-CT scanning and bone analysis on the harvested joints and modulated serum RANKL and OPG levels. Overall, our findings suggest that CB2 agonist JWH-015 elicits anti-inflammatory effects partly through GR. This compound could further be tested as an adjunct therapy for the management of pain and tissue destruction as a non-opioid for RA