Interlayer Exchange Coupling Mediated by Valence Band Electrons

The interlayer exchange coupling mediated by valence band electrons in all-semiconductor IV-VI magnetic/nonmagnetic superlattices is studied theoretically. A 3D tight-binding model, accounting for the band and magnetic structure of the constituent superlattice components is used to calculate the spin-dependent part of the total electronic energy. The antiferromagnetic coupling between ferromagnetic layers in EuS/PbS superlattices is obtained, in agreement with the experimental evidences. The results obtained for the coupling between antiferromagnetic layers in EuTe/PbTe superlattices are also presented.Comment: 8 pages, 6 figures, to be submitted to Phys.Rev.

Smart solution for reducing COVID-19 risk using internet of things

The article exposes a smart device designed for mitigating the coronavirus disease (COVID-19) risk using the internet of things. A portable smart alerting device is designed for ensuring safety in public places which can alert people when the guidelines given by the government were not followed and alert health authorities when any abnormalities found. By doing so, the spread of this fatal disease can be stopped. The modules of the proposed system include the face mask detection module, social distance alerting module, crowd detection and analysis module, health screening module and health assessment module. The proposed system can be placed in any public entrances to monitor people without human intervention. Firstly, the human face images are captured for face mask check, then the crowd analysis of the particular entrance where the person is entering is performed, thereafter health screening of the person is done and the values were imported to the health assessment module to check for any abnormalities. Finally, after all the conditions were met the door is opened automatically. The smart device can be installed and effectively used in many scenarios such as malls, stores, crowded places and campuses to avoid the risk of spread of the coronavirus

EFFECTS OF PROCESS PARAMETERS AND OPTIMIZATION OF MECHANICAL AND METALLURGICAL BEHAVIOUR FOR DISSIMILAR MATERIAL BY ELECTRICAL RESISTANCE SPOT WELDING.

Electrical resistance Spot Welding is a pressure welding used for joining of sheet metals or wires. The welding heat is produced at the desired location by electrical resistance through the metal pieces. ERSW is highly used due to its fast rate of production, less maintenance, free from smoke etc… ERSW is experimented in dissimilar materials (Stainless steel –Mild steel) to analyze the effect of process parameters such as welding current, welding time and electrode force. The welded parts were applicable to tensile test and hardness test .Thus the influence of parameters on weld quality was categorized

ANALYSIS AND OPTIMIZATION OF FRICTION WELDING PARAMETERS FOR AA6061-AA2014 DISSIMILAR JOINTS

Friction welding is a solid state welding used owing to its properties such as low heat input, high production efficiency and environment friendliness. Materials which aredifficult towelded by fusion welding processes can be successfully done friction welding. In this work, an effort was made to predict the maximum tensile strength of friction welded AA 6061 and AA 2014 aluminium alloy dissimilar joints incorporating the process parameters such as rotational speed, friction pressure and forging pressures which have immense on the strength of joints. The friction welding process parameters were optimized to achieve maximum tensile strength of the joint. The maximum tensile strength of 210MPa  for the joints fabricated under the welding conditions ofrotational speed 1508 rpm, friction pressure of 8.16 MPa/secand forging pressure of 6.79 MPa/sec using the optimization techniques

Preventing Denial-of-service in Next Generation Internet Protocol Mobility

Internet Protocol version 6 (IPv6) is a next-generation internet protocol that is devised to replace its predecessor, the IPv4. With the benefit of ample address space, flexible header extensions and its many specific features, IPv6 is the future of the Internet and Internetworking. A significant advantage of IPv6 is its capabilities in the domain of security and mobility, where it scores in comparison with its predecessor. One of the many features specific to IPv6, such as the mandatory IPsec messaging or address auto-configuration, is the Neighbor Discovery Protocol (NDP). Even though the concept of security is more pronounced in the IPv6 protocols, there still exist loopholes. These loopholes when exploited target the foundation of the Internetworking. The extensive applications of NDP make it even more necessary to identify and address these gaps to ensure network security. Hence, this paper investigates such loopholes in the applications of NDP in creating a network and analyzes the process of the denial-of-service attacks that endanger the safety of an established network. Also, the paper proposes a new method to mitigate Denial-of-Service (DoS) in network mobility of IPv6 networks. This proposed approach is a hybrid of existing solutions and is capable of overcoming the significant disadvantages of these methods. Also, the paper discusses the comparative analysis among the various existing solutions and illustrates the effect of the proposed method in MIPv6 security

An Efficacious and Secure Registration for Internet Protocol Mobility

For the ample development of mobile internet protocol (IP) technology and the recurrent movement of a mobile device, it is necessary for the mobile device to inform their home network where initially registered through an efficient and secured procedure against any sort of attacks. The procedure of registration for IP mobility by the portable system must have a better performance by providing a certain level of security, such as authentication, integrity, replay attack protection, and location privacy. All at once, the extreme security in the registration of IP mobility may cause long registration time, principally for real-time systems. This paper mainly deals with a balanced effort for secure and efficient registration procedure which gives better security and efficiency in terms of registration delay. The proposed work provides an easy and fast registration procedure and lessens the registration delay through the usage of an identity based authenticated key exchange scheme that eliminates expensive pairing operations. The proposed protocol is verified by using AVISPA tool. The performance evaluation reveals that the proposed protocol significantly outperforms the existing protocols in terms of the registration delay.Defence Science Journal, 2013, 63(5), pp.502-507, DOI:http://dx.doi.org/10.14429/dsj.63.400

The Reasons for the Poor Achievement of Students in the Three Basic Grades in Reading and Ways to Address Them from the Point of View of Teachers

This study aimed to identify the reasons for the poor achievement of students in the first three grades in reading from the teachers\u27 point of view and ways to address them, and in order to achieve the desired objectives of the study. (35) schools were selected using a simple random sampling method out of (51) schools, and (100) teachers were selected from these schools out of (300) male and female teachers at a rate of 30%, and an opinion poll was conducted for (25) teachers of the basic stage , from the first to the third grade of the Deir Alla District Directorate. The researcher used a questionnaire as a tool that she prepared to achieve the objectives of the study, which consisted of (14) paragraphs. The study concluded at the total level that the degree of weakness was high, due to the reasons for weakness in the field of reading, with an arithmetic mean (3.86) and a standard deviation (.53), and the number of The paragraphs that got a high degree of weakness (10), and the number of paragraphs that got a medium degree of weakness (4). Among the results of ways to treat poor reading that ranked first is the paragraph that states that students’ tendencies and desires are taken into account while writing school books in light of the achieved results, at a rate of (20%), and the paragraph that got the lowest degree of weakness, the paragraph that states that students should be involved in the radio school at a rate of 4%. The researcher reached some recommendations that she recommends, including the need to reduce the frequent absence of students from school, through communication between school and home. And the development of teachers of the stage professionally, by training them on everything new in the methods of teaching reading, and informing them about the basics of teaching students of the first three grades, especially reading, and emphasizing the importance of training teachers during the service, on new and modern teaching methods for reading. And taking into account the importance of the diagnostic evaluation of students at the beginning of the school year and the semester, and raising the teachers’ awareness of that and following them up by their supervisors through periodic visits to them during the school year, to find out the strengths and weaknesses of each studen