Combined effects of Hall current and variable Viscosity on Non-Newtonian MHD flow past a stretching vertical plate

This paper investigate the effects of Hall currents on free-convective steady laminar boundary-layer flow, past a semi-infinite vertical plate, for large temperature differences . A uniform magnetic field is applied perpendicular to the plate. The fluid thermal conductivity is assumed to vary as a linear function of temperature. The fluid viscosity is assumed to vary as a reciprocal of a linear function of temperature. The usual Boussinesq approximation is neglected. The nonlinear boundary layer equations governing the problem under consideration are solved numerically by applying an efficient numerical technique based on the shooting method. The effects of the magnetic parameter M, the density / temperature parameter n, the thermal conductivity parameter S, the viscosity temperature  are examined on the velocity and temperature distribution as well as the coefficient of heat flux and shearing stress at the plate

Performance Assessment of Unsupervised Clustering Algorithms Combined MDL Index

Best clustering analysis should be resisting the presence of outliers and be less sensitive to initialization as well as the input sequence ordering. This chapter compares the performance among three of the unsupervised clustering algorithms: neural gas (NG), growing neural gas (GNG), and robust growing neural gas (RGNG). A complete explanation of NG and GNG algorithms is presented in the next comparison with RGNG. Another comparison due to the minimum description length (MDL) criterion between RGNG used MDL value as the clustering validity index versus GNG and NG combined with MDL. Statistical estimations are applied to explain the meaning of the output results when these algorithms are fed to the synthetic 2D dataset. The techniques introduced in this chapter are designed and implemented in a simple software package using a MATLAB-based graphical user interface (GUI) tool, which allows users to interact with the clustering techniques and output data easily

Evaluation the effectiveness of a non-chopped basalt fiber and water-based of isocyanate-polyester polyol prepolymer on the properties of cement fiberboard

Abstract Cement board reinforced with basalt fibers were prepared by using polymer compounds, 5% of water-based of isocyanate-polyester polyol prepolymer blend was used as a fixed percentage, and the rates of basalt fıber used were 5%, 7.5%, 10%, 12.5%, and for each of them used water/cement ratios (W/C) as 1.4, 1, 0.75, 0.4, and 0.5 respectively. The sample cured for 28 days, and the mechanical and physical properties of cement fiberboard were greatly improved due to additional fibers in cement compounds, the tests procedures of properties were carried out according to ASTM standard c-1185. It results reveals that 12.5% is the best percentage, in bending resistance, water absorption percentage, and the moisture content have improved, but it showed less thermal conductivity compared to other ratios, furthermore the compressive strength was improved. It is essential to indicate when increasing the polymer ratio, leads to a certain decrease in mechanical properties but improves the wetting surface of the basalt fibers and adhesion to cement. Therefore, a 5% polymers ratio chooses and the basalt fıber mix proportions changed to enhance the mechanical and physical properties of fiber boar

Trace Properties from Separation Logic Specifications

We propose a formal approach for relating abstract separation logic library specifications with the trace properties they enforce on interactions between a client and a library. Separation logic with abstract predicates enforces a resource discipline that constrains when and how calls may be made between a client and a library. Intuitively, this can enforce a protocol on the interaction trace. This intuition is broadly used in the separation logic community but has not previously been formalised. We provide just such a formalisation. Our approach is based on using wrappers which instrument library code to induce execution traces for the properties under examination. By considering a separation logic extended with trace resources, we prove that when a library satisfies its separation logic specification then its wrapped version satisfies the same specification and, moreover, maintains the trace properties as an invariant. Consequently, any client and library implementation that are correct with respect to the separation logic specification will satisfy the trace properties

An efficient data Parallelization of the Radix-23 (Carbon) FFT on GPU/CPU

Solving Complex Problem that is coupled with intensive workloads; necessities the access to a massively parallel computational power. Up to date, Graphic Processing Units (GPUs) are the only architecture that could handle the most complex computationally intensive workloads. In the light of this rapid-growing advancement in computational technologies, this paper will propose a high-performance parallel radix-23 FFT suitable for such GPU and CPU systems. The proposed algorithm could reduce the computational complexity by a factor that tends to reach pr if implemented in parallel (pr is the number of cores/threads) plus the combination phase to complete the required FFT

COVID-19 Vaccine Acceptance among Ajman Undergraduate Dental Students: A Cross-Sectional Study.

BACKGROUND Achieving widespread coronavirus disease 2019 (COVID-19) vaccination is crucial in controlling the pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). This cross-sectional study aimed to identify factors associated with the willingness of dental medicine students to receive the COVID-19 vaccine. OBJECTIVES The study sought to assess the knowledge, attitudes, and behaviors of undergraduate dental students toward COVID-19 vaccines and to identify determinants, motivators, and barriers to vaccine uptake and booster receipt. METHODS A web-based survey was distributed to all 882 undergraduate dental surgery students in January 2022, and 70.7% of the students responded. The survey used χ2 tests and logistic regression analysis to examine the association among the variables. The significance level was set at α = 0.05. RESULTS Most participants (72.4%) reported having adequate knowledge of COVID-19. The vaccine acceptance rate was higher among male and older trainees, with no significant difference compared to women and younger trainees with no significant difference (p = 0.849). Acceptance of the vaccine varied according to study level (5-year program), ranging from 44.8% to 73.0%, in the following order 4th > 1st > 3rd > 5th > 2nd year. Social media (76.8%), government websites (66.5%), and family and friends (57.2%) were the main sources of COVID-19-related information. Among hesitant and unwilling participants, the main concerns were side effects (34.0%) and lack of understanding about the vaccine's mechanism (67.3%). CONCLUSIONS Ajman dental students had moderate knowledge of COVID-19 and obtained information mainly from social media, government websites, and family and friends. Age, sex, and study year influenced vaccine acceptance. The main reasons for refusal were lack of knowledge, fear of side effects, and complications. Education campaigns are needed to increase vaccine acceptance among dental students

Investigation of the Electrochemical Properties of CoAl-Layered Double Hydroxide/Ni(OH)2

Layered double hydroxides (LDH) as active electrode materials have become the focus of research in energy storage applications. The manufacturing of excellent electrochemical performance of the LDH electrode is still a challenge. In this paper, the production of CoAl-LDH@Ni(OH)2 is carried out in two steps, including hydrothermal and electrodeposition techniques. The prominent features of this electrode material are shown in the structural and morphological aspects, and the electrochemical properties are investigated by improving the conductivity and cycle stability. The core of this experimental study is to investigate the properties of the materials by depositing different amounts of nickel hydroxide and changing the loading of the active materials. The experimental results show that the specific capacity is 1810.5F·g−1 at 2 A/g current density and the cycle stability remained at 76% at 30 A g−1 for 3000 cycles. Moreover, a solid-state asymmetric supercapacitor with CoAl-LDH@Ni(OH)2 as the positive electrode and multi-walled carbon nanotube coated on the nickel foam as the negative electrode delivers high energy density (16.72 Wh kg−1 at the power density of 350.01 W kg−1). This study indicates the advantages of the design and synthesis of layered double hydroxides, a composite with excellent electrochemical properties that has potential applications in energy storage

Quantum three-body system in D dimensions

The independent eigenstates of the total orbital angular momentum operators for a three-body system in an arbitrary D-dimensional space are presented by the method of group theory. The Schr\"{o}dinger equation is reduced to the generalized radial equations satisfied by the generalized radial functions with a given total orbital angular momentum denoted by a Young diagram $[\mu,\nu,0,...,0]$ for the SO(D) group. Only three internal variables are involved in the functions and equations. The number of both the functions and the equations for the given angular momentum is finite and equal to $(\mu-\nu+1)$.Comment: 16 pages, no figure, RevTex, Accepted by J. Math. Phy