Secure Mobile Commerce in Ad hoc Network Using CAEC2M

Khaleel Ahmad,Md Shoaib Alam,M A Rizvi 보안공학연구지원센터 2016 International Journal of Future Generation Communi Vol.9 No.12

M-Commerce applications in the world have grown exponentially over the years. It had set up for mobile users to engage wirelessly of ad hoc network infrastructure in online business irrespective of place or time. Providing anonymous, secure and trust based connection service in ad hoc network is quite a challenging task. Anonymity, security and privacy of the transaction or message transmission are the highest priority need to be delivered to the destination node on time. In this paper, a CAEC2M (Cellular Automata Elliptic Curve Cryptography Mix network) algorithm to secure Mobile Commerce over ad hoc network is proposed. An attempt is made to design a mix-network (Mix-Net) using elliptic curve cryptography based on cellular automata which creates a hard to trace communication to protect the anonymity of the sender and encrypt the sensitive information to avoid any eavesdropper trying to access the data during transmission. CAEC2M provides also confidentiality, integrity and authentication.

Droplets behavior impacting on a hot surface above the Leidenfrost temperature

Hamdan, Khaleel Sami,Kim, Dong-Eok,Moon, Sang-Ki Elsevier 2015 Annals of nuclear energy Vol.80 No.-

<P><B>Abstract</B></P> <P>Experimental studies of droplet behaviors impacting on a hot surface above the Leidenfrost temperature have been performed to provide improvements in the modeling of heat transfer in a ballooned surface characteristic of a loss-of-coolant accident (LOCA). Droplets of known size and velocity were impacted on a hot surface above the Leidenfrost temperature. The spreading of droplets into a liquid film on the surface and the breakup of the droplets were observed using a high-speed camera. For droplets of higher normal Weber number than a threshold value, the higher the normal Weber number of the droplet the smaller the secondary droplets. The conventional correlations showed fairly good agreements with the maximum spreading diameters of the droplets on the hot surface. On the other hand, the size of the secondary droplets resulting from an impact upon the hot surface was not well predicted by the COBRA-TF correlation. A new improved model for the secondary droplet size was developed using the mass conservation with a correction factor. The new model showed good predictions of the secondary droplet size for the present experiment as well as other experiments.</P> <P><B>Highlights</B></P> <P> <UL> <LI> The droplet behaviors impacting on a hot surface above the Leidenfrost temperature has been performed. </LI> <LI> The droplet diameters, velocities, and spreading diameters were measured. </LI> <LI> The COBRA-TF correlation over-predicts the breakup size of secondary droplets. </LI> <LI> A new model for the breakup size of secondary droplets was developed. </LI> <LI> The new model predicts the present experiments as well as other experiments. </LI> </UL> </P>

Use of social media in education among medical students in Saudi Arabia

Anas Khaleel Alsuraihi,Ahmed Saeed Almaqati,Sultan Adnan Abughanim,Nisreen Abdulrahman Jastaniah 한국의학교육학회 2016 Korean journal of medical education Vol.28 No.4

Purpose: Social media (SM), a virtual place where people can share, exchange, and communicate their ideas and knowledge, has become the new trend in communication and learning. This study aims to explore Saudi Arabian medical students’ usage of SM and to discover the most common resources used in medical education. Furthermore, it aims to illustrate students’ belief about the influence of SM on their learning. Methods: This cross-sectional study administered validated questionnaires to medical students from different universities in Saudi Arabia, via emails, Twitter, Facebook, and short message service. A non-probability sampling technique was utilized and a sample size of 381 students was arrived at, using 95% confidence interval and 5% margin of error, since the total number of medical students in Saudi Arabia is approximately 36,000. The total respondents were 657 students from 23 different Saudi Arabian medical schools (females: 60.5%, n=397; males: 39.5%, n=260). Results: The questionnaires of 21% of the students (n=139) were excluded from the analysis since they were incomplete. The most common website used by both genders was YouTube (42.3%, n=185); however, males preferred using Twitter and Wikis (p=0.001). With regard to utilizing SM for learning, 95.8% (n=419) of the students believed that it is beneficial. Females stated that SM helps them link basic and clinical science (p=0.003). Conclusion: Medical schools need to improve the utilization of SM by their faculty and students by developing activities and encouraging the usage of SM in education.

Impact of Social Networks in Educational Media

Al-Said, Khaleel M.,Al Said, Nidal,Hattab, Ezz The Korea Institute of Information and Commucation 2020 Journal of information and communication convergen Vol.18 No.4

This study aims to determine whether student participation on Twitter affects academic performance. The key goals of the training course were to acquire social networking knowledge and skills and to learn how to share information, be productive in discussions, and create an interest-based community. The initial sample comprised 286 students from Jordan universities, 68.4% of whom agreed to participate in the study. Undergraduate students accounted for 73.9%, and graduate students accounted for 26.1%. Only 14.3% of the students chose the Twitter-based learning model. This is a mixed-methods study that integrates quantitative and qualitative approaches. The undergraduate students were found to tweet more and have more likes, while graduate students had more followers and were following more accounts. Moreover, 21% of the participants were the most active. Spearman's correlation analysis revealed a connection between participation in social media and student performance. Therefore, the results of this study may help educational professionals and education managers.

INFLUENCE OF DIFFERENT UV EXPOSURE TIME ON THE CFRP/ALUMINUM SINGLE LAP JOINTS STRENGTH AND FRACTURE MODES

Salah Mahdi Khaleel,Bernard Rolfe,Riyadh Al-Ameri,Tim Hiliditch 한국자동차공학회 2019 International journal of automotive technology Vol.20 No.2

The urging need to reduce the harmful emissions required a thorough investigations into the methods of utilizing the dissimilar lightweight materials in modern automobile, aviation and marine industries. With the exception use of dissimilar materials, traditional joining methods become limited or incapable to maintain safety standards. The adhesive bonding, therefore, seems an ideal choice to overcome this limitation due to uniform stress distribution, fatigue resistance and sound isolation. However, the role of environmental degradation become vital in the areas where the joints exposed directly or indirectly to the sunlight, humidity and extreme change in the temperature. With such key industries, intensive work to comply with safety standards are crucial. The current work devoted to examining the influence of Ultra-Violet (UV) exposure on three different Carbon Fiber Reinforced Polymer (CFRP) setup of Aluminum-CFRP single lap joint with respect to strength and fracture mode. The samples exposed to the specified UV dosage of three exposure duration then tested mechanically based on ASTM standards. The outcomes indicate that the fracture modes are highly affected by the CFRP orientation as well as the UV exposure time. Moreover, the joint strength decreases with increases of the UV exposure time.

Altered Cell to Cell Communication, Autophagy and Mitochondrial Dysfunction in a Model of Hepatocellular Carcinoma: Potential Protective Effects of Curcumin and Stem Cell Therapy

Tork, Ola M,Khaleel, Eman F,Abdelmaqsoud, Omnia M Asian Pacific Journal of Cancer Prevention 2015 Asian Pacific journal of cancer prevention Vol.16 No.18

Background: Hepato-carcinogenesis is multifaceted in its molecular aspects. Among the interplaying agents are altered gap junctions, the proteasome/autophagy system, and mitochondria. The present experimental study was designed to outline the roles of these players and to investigate the tumor suppressive effects of curcumin with or without mesenchymal stem cells (MSCs) in hepatocellular carcinoma (HCC). Materials and Methods: Adult female albino rats were divided into normal controls and animals with HCC induced by diethyl-nitrosamine (DENA) and $CCl_4$. Additional groups treated after HCC induction were: Cur/HCC which received curcumin; MSCs/HCC which received MSCs; and Cur+MSCs/HCC which received both curcumin and MSCs. For all groups there were histopathological examination and assessment of gene expression of connexin43 (Cx43), ubiquitin ligase-E3 (UCP-3), the autophagy marker LC3 and coenzyme-Q10 (Mito.Q10) mRNA by real time, reverse transcription-polymerase chain reaction, along with measurement of LC3II/LC3I ratio for estimation of autophagosome formation in the rat liver tissue. In addition, the serum levels of ALT, AST and alpha fetoprotein (AFP), together with the proinflammatory cytokines $TNF{\alpha}$ and IL-6, were determined in all groups. Results: Histopathological examination of liver tissue from animals which received DENA-$CCl_4$ only revealed the presence of anaplastic carcinoma cells and macro-regenerative nodules. Administration of curcumin, MSCs; each alone or combined into rats after induction of HCC improved the histopathological picture. This was accompanied by significant reduction in ${\alpha}$-fetoprotein together with proinflammatory cytokines and significant decrease of various liver enzymes, in addition to upregulation of Cx43, UCP-3, LC3 and Mito.Q10 mRNA. Conclusions: Improvement of Cx43 expression, nonapoptotic cell death and mitochondrial function can repress tumor growth in HCC. Administration of curcumin and/or MSCs have tumor suppressive effects as they can target these mechanisms. However, further research is still needed to verify their effectiveness.

Effect of Heat-Treatment Temperature on the Corrosion Behaviour of Cold Worked 6111 Aluminium Alloy

Jamal Nayief Sultan,Majid Khaleel Najem,Emad Toma Karash Korean Society for Precision Engineering 2021 한국정밀공학회지 Vol.38 No.6

Deoxygenation of vegetable oils and fatty acids: How can we steer the reaction selectivity towards diesel range hydrocarbons?

Sara Alkhoori,Maryam Khaleel,Lourdes F. Vega,Kyriaki Polychronopoulou 한국공업화학회 2023 Journal of Industrial and Engineering Chemistry Vol.127 No.-

Fast pyrolysis is a prominent and versatile process that involves thermal decomposition of biomass feedstocksto produce high volumes of liquid bio-oil, which may eventually be upgraded via deoxygenationpathways (hydrodeoxygenation, decarboxylation, or decarbonylation) into high energy content greenfuels like gasoline, diesel and jet fuel. The quality of the bio-oil, its thermal stability, heating value,and the efficiency of the total conversion process can be improved by deoxygenation over properlydesigned catalysts. Despite the success of the available catalysts to significantly improve bio-oil qualityby producing useful aromatic hydrocarbons, phenolics, or alkanes, there are still opportunities for furtherimprovements of the catalytic performance with regards to their activity, product selectivity and resistivityagainst deactivation. The present work provides a comprehensive analysis of the recent developmentsof sulfur-free monometallic and bimetallic transition metal and noble metal supported catalysts forselective deoxygenation of vegetable oils and fatty acids model compounds for biofuel production. Theattention focuses on the design of active sites on these catalysts as well as the acidic nature of the integratedsupports for selectively manipulating mechanistic pathways. Moreover, this review emphasizes onthe role of doping in stabilizing metal oxides to tune metal-support interaction (MSI) and electron donationproperties, all strategies combined for the enhancement of biofuel production. The novelty of thisreview lies on bridging theoretical and experimental investigations aiming at describing and interpretingdeoxygenation pathways of vegetable oils and related model compounds. Current challenges and perspectiveare also provided.

Design and Synthesis of Thienotropone-Containing Conjugated Polymers

김경수,안종호,Zinah Hilal Khaleel,송창식 한국고분자학회 2014 한국고분자학회 학술대회 연구논문 초록집 Vol.2014 No.10

Synthesis of electroconductive hydrogel films by an electro-controlled click reaction and their application to drug delivery systems

Choi, Eun Jung,Shin, Jisoo,Khaleel, Zinah Hilal,Cha, Inhwan,Yun, Sang-Ho,Cho, Seung-Woo,Song, Changsik The Royal Society of Chemistry 2015 Polymer chemistry Vol.6 No.24

<▼1><P>Electroconductive hydrogels are composed of 3-dimensionally structured hydrogels and conducting molecules with electrical, optical, and reversible redox properties.</P></▼1><▼2><P>Electroconductive hydrogels are composed of 3-dimensionally structured hydrogels and conducting molecules with electrical, optical, and reversible redox properties. These hybrid materials can be utilized as electrically-stimulated biomaterials in implantable biosensors or drug delivery systems. In this study, carbon nanotube-incorporated polyvinyl alcohol (PVA)-based hydrogels were synthesized by an electro-click reaction, which was controlled by an electrochemically generated Cu(i) catalyst. When the reduction potential of Cu(ii) ions was applied, PVA-based hydrogels were deposited onto indium-tin-oxide-coated glass electrodes <I>via</I> Cu(i)-catalysed alkyne–azide cycloaddition (click reaction). When the hydrogels contained carbon nanotubes, thicker films were deposited because the embedded carbon nanotubes provided a larger electrochemical active area. In addition, the carbon nanotubes improved the electrical conductivity of the hydrogel systems. We investigated the electro-stimulated drug release behaviour with electro-click conductive hydrogels using tetracycline as a model drug.</P></▼2>