Steady conjugate natural convection heat transfers in a two-dimensional enclosure filled with fluid saturated porous medium is studied numerically. The two vertical boundaries of the enclosure are kept isothermally at same temperature, the horizontal upper wall is adiabatic, and the horizontal lower wall is partially heated. The Darcy extended Brinkman Forcheimer model is used as the momentum equation and Ansys Fluent software is utilized to solve the governing equations. Rayleigh number (1.38 ≤ Ra ≤ 2.32), Darcy number (3.9 * 10-8), the ratio of conjugate wall thickness to its height (0.025 ≤ W ≤ 0.1), heater length to the bottom wall ratio (1/4 ≤ ≤ 3/4) and inclination angle (0°, 30° and 60°) are the main considered parameters. The presented results show the effect of these parameters on the heat transfer and fluid flow characteristics. These results include streamlines, isotherm patterns, and local and average Nusselt number for different values of the governing parameters. It is found that either increasing the Rayleigh number and the ratio of conjugate wall thickness to its height (d/H) or decreasing the ratio of heat source width to bottom wall (l/L), the average Nusselt number is increased. Also, it was observed that the average Nusselt number does not change substantially with inclination angle.
A Multiple System Biometric System Based on ECG Data
Globally, the COVID-19 pandemic’s development has presented significant societal and economic challenges. The carriers of COVID-19 transmission have also been identified as asymptomatic infected people. Yet, most epidemic models do not consider their impact when accounting for the disease’s indirect transmission. This study suggested and investigated a mathematical model replicating the spread of coronavirus disease among asymptomatic infected people. A study was conducted on every aspect of the system’s solution. The equilibrium points and the basic reproduction number were computed. The endemic equilibrium point and the disease-free equilibrium point had both undergone local stability analyses. A geometric technique was used
... Show MoreIn this paper, the botnet detection problem is defined as a feature selection problem and the genetic algorithm (GA) is used to search for the best significant combination of features from the entire search space of set of features. Furthermore, the Decision Tree (DT) classifier is used as an objective function to direct the ability of the proposed GA to locate the combination of features that can correctly classify the activities into normal traffics and botnet attacks. Two datasets namely the UNSW-NB15 and the Canadian Institute for Cybersecurity Intrusion Detection System 2017 (CICIDS2017), are used as evaluation datasets. The results reveal that the proposed DT-aware GA can effectively find the relevant features from
... Show MoreThis research investigates new glasses which are best suitable for design of optical systems
working in the infrared region between 1.01 to 2.3μm. This work is extended to Oliva & Gennari
(1995,1998) research in which they found that the best known achromatic pairs are (BAF2-IRG2; SRF2-
IRG3; BAF2-IRG7; CAF2-IRGN6; BAF2-SF56A and BAF2-SF6). Schott will most probably stop the
production of these very little used and commercially uninteresting IRG glasses. In this work equally
good performances can be obtained by coupling BAF2, SRF2&CAF2 with standard glasses from Schott
or Ohara Company. The best new achromatic pairs found are (SRF2-S-TIH10; CAF2-S-LAL9; CAF2-SLAL13
and CAF2-S-BAH27). These new achromatic pai
Ketoprofen has recently been proven to offer therapeutic potential in preventing cancers such as colorectal and lung tumors, as well as in treating neurological illnesses. The goal of this review is to show the methods that have been used for determining ketoprofen in pharmaceutical formulations. Precision product quality control is crucial to confirm the composition of the drugs in pharmaceutical use. Several analytical techniques, including chromatographic and spectroscopic methods, have been used for determining ketoprofen in different sample forms such as a tablet, capsule, ampoule, gel, and human plasma. The limit of detection of ketoprofen was 0.1 ng/ ml using liquid chromatography with tandem mass spectrometry, while it was 0
... Show MoreThe aim of the current research is to construct a scale of emotional adjustment for kindergarten children and to set a standard for its evaluation. To achieve this, a scale consisting of (19) items was prepared. The mother of the child answered by adopting the method of self-report, which is expressed in the form of reporting terms, as each item represents a situation in the child's life and each situation has three alternatives to answer that represent various responses to the mentioned situation. One of the alternatives represents the emotionally adaptive response, which is given a degree (3), the second response expresses the emotional adjustment partly that took the degree of (2), and the third response expresses the weakness of emot
... Show MoreThis study aims to focus on the Motives behind volunteer work among a sample of volunteers working in civil society organizations and check if there are statistical differences with those variables according to (gender, age, job, period of volunteer work, and residence. The sample consists of (220 )volunteers,(189) male and(31) female from southern, northern and central governorate .The Volunteer Functions Inventory(VFI)(Clary & et al,1989)was applied, It consisting of(30) items with six fields( Values, Understanding, Social motives, Career, Protective, Enhancement).
The results show that the most common and important motivations are (Values, Understanding, and social motivations), there are differenc
... Show MoreTechnological development in the last years leads to increase the access speed in the internet networks that allow a huge number of users watching videos online.
Video streaming important type in the real-time video sessions and one of the most popular applications in networking systems. The Quality of Service (QoS) techniques give us indicate to the effect of multimedia traffic on the network performance, but this techniques do not reflect the user perception. Using QoS and Quality of Experience (QoE) together can give guarantee to the distribution of video content according to video content characteristics and the user experience .
To measure the users’ perceptio
... Show MoreSentiment Analysis is a research field that studies human opinion, sentiment, evaluation, and emotions towards entities such as products, services, organizations, events, topics, and their attributes. It is also a task of natural language processing. However, sentiment analysis research has mainly been carried out for the English language. Although the Arabic language is one of the most used languages on the Internet, only a few studies have focused on Arabic language sentiment analysis.
In this paper, a review of the most important research works in the field of Arabic text sentiment analysis using deep learning algorithms is presented. This review illustrates the main steps used in these studies, which include
... Show MoreThe administrative authority (the administration) exercises its activity or work through two forms of business. This administrative act in which the intention of the administrative authority (the administration) is to have a specific legal effect. The risk, and whether the administration is restricted or discretionary in exercising its authority in the licensing area, it must not deviate from the legitimacy framework.
Accordingly, and to be informed of this, we divide our study into three sections, in the first of which we deal with the definition of administrative licenses, and in the second of it we explain the competent authority for administrative licenses in comparative law, and in the third we highlight the authority concer
... Show More