Graphical One-Time Password (GOTPass): A usability evaluation

Journal has two ISSNs: 1939-3555 (Print), 1939-3547 (Online)Complying with a security policy often requires users to create long and complex passwords to protect their accounts. However, remembering such passwords is difficult for many and may lead to insecure practices, such as choosing weak passwords or writing them down. In addition, they are vulnerable to various types of attacks, such as shoulder surfing, replay, and keylogger attacks (Gupta, Sahni, Sabbu, Varma, & Gangashetty, 2012) One-Time Passwords (OTPs) aim to overcome such problems (Gupta et al., 2012); however, most implemented OTP techniques require special hardware, which not only adds cost, but there are also issues regarding its availability (Brostoff, Inglesant, & Sasse, 2010). In contrast, the use of graphical passwords is an alternative authentication mechanism designed to aid memorability and ease of use, often forming part of a multifactor authentication process. This article is complementary to the earlier work that introduced and evaluated the security of the new hybrid user-authentication approach: Graphical One-Time Password (GOTPass) (Alsaiari et al., 2015). The scheme aims to combine the usability of recognition-based and draw-based graphical passwords with the security of OTP. The article presents the results of an empirical user study that investigates the usability features of the proposed approach, as well as pretest and posttest questionnaires. The experiment was conducted during three separate sessions, which took place over five weeks, to measure the efficiency, effectiveness, memorability, and user satisfaction of the new scheme. The results showed that users were able to easily create and enter their credentials as well as remember them over time. Participants carried out a total of 1,302 login attempts with a 93% success rate and an average login time of 24.5s

Teaching Arabic through communicative language teaching approaches informed by new understandings of literacy in primary schools in Tabuk, Saudi Arabia

This thesis seeks to document the perspectives of 24 male primary educators of the Arabic language on teaching Arabic through communicative language teaching (CLT) approaches informed by the new literacy theory (NLT) in Saudi Arabia (Tabuk). In Saudi Arabia, there is little focus on the importance of communication skills in using Standard Arabic, whether in conversation, listening and speaking. This study aims to fill the gap in the research literature on Arabic language teaching in primary education, drawing on the NLT. Arabic is a global language and this study has international significance as the findings will inform the teaching of Arabic as a first and additional language. Therefore, this study investigates the usage of CLT approaches into the teaching of Arabic through the use of various activities that are contextual and meaningful. The focus of this study is on language in relation to listening, speaking, viewing, reading, writing, critiquing and creating in purposeful contexts. It utilises a mixed method mainly drown on qualitative research methods to examine five case study sites (government primary schools in urban Tabuk) to investigate the use of technology in Standard Arabic Teaching using CLT approaches. Furthermore, the study examines the use of a contemporary curriculum in order to contrast it to traditional approaches. Data was initially gathered with a survey to collect demographic data about the study and its subjects. Participants were then interviewed to obtain deeper and more detailed information. The study covered five schools and four supervisors. Moreover, this study draws on connectivism theory, which presents a concept of information being presented via complex networks that enable the educational process to occur. In the connectivism theory, learning occurs via networks through a mix of technological and social interactions. The findings indicate that there is a lack of understanding the NLT, and tensions between traditional and contemporary curriculum supporters exist. The professional development and academic preparation (pre-service) received by students in colleges and universities was one of the most prominent findings in this study, because it shows a weakness in the preparation that student teachers receive in educational institutions. In addition, the findings highlight issues in providing information technology (IT), access to the use of technology, leadership and change. In conclusion, this study revealed that curriculum change in Saudi Arabia is a controversial topic in relation to Saudi societal ideologies. In particular, the study highlighted that curriculum change, leadership, contemporary views of literacy learning and Arabic education are as important as other issues such as religion, Arabic identity, resistance to change and Westernisation. Hence, this study points to the significance of professional development in curriculum change where teachers, principals, educators, curriculum designers, policy makers and parents are involved in the development of curriculum in order to provide high quality education for their children

Urban sprawl in desert cities : the case studies of Phoenix, Arizona and Riyadh, Saudi Arabia

The growth of the world’s cities is unavoidable as long as the population continues to increase. However, it is important that these cities grow and develop in a responsible manner in order to avoid harmful urban sprawl. Sprawl is problematic because it is unsustainable. Urban sprawl leads to unnecessary expenses, rapid use of resources, including limited land space, and environmental problems. Sprawl within the desert regions is particularly problematic due to their lack of resources and the artificial environment they currently necessitate. Here two comparable, however, culturally dissimilar desert cities are compared and analyzed to better understand desert city sprawl and how it is dealt with in hopes of obtaining knowledge that can be later applied to the development of solutions. It is determined through this analysis that urban sprawl, particularly in desert cities, will most likely continue in their problematic nature until laws and policies are developed and public mindsets changed to make desert living more compatible with the surrounding environment

Gas-Gas Separation Using a Hollow Fiber Membrane

Computational fluid dynamics simulations are conducted for laminar steady asymmetric flows within a hollow fiber membrane unit. The goal is to study the effect of the porous layer of a hollow fiber membrane (HFM) on the flow regimes and thus on the separation process. The mixture of CH4 and CO2 is studied with the goal of separating CO2 from CH4. The hollow fiber membrane consists of a circular channel bounded by a supporting porous layer. Outer surface of the tubular pipe is bounded by a selective membrane. The Navier-Stokes equation, Darcy\u27s law, and the species transport equations are solved for various values of permeability of the porous medium and Reynolds numbers. The mass flux of each species passing through the membrane is determined based on the local partial pressure, the concentration of each species, the permeability and the membrane selectivity. The porous layer influences the flow field in the open channel strongly. With increasing resistance the flow rate through the porous medium decreases. The flow rate through the open channel increases as the resistance of the porous layer is increased. The presence of the porous layer results in the reduction of mass flux of both CH4 and CO2 passing through the membrane. The Sherwood number is reduced at all Re as the resistance of the porous layer is increased. The increased resistance of the porous layer also causes an increase in the pressure drop in the hollow fiber membrane module. The present study proves that the porous layer should be included in modeling of hollow fiber membrane systems

Oxidative carboxylation of 1-decene to 1,2-decylene carbonate

Cyclic carbonates are valuable chemicals for the chemical industry and thus, their efficient synthesis is essential. Commonly, cyclic carbonates are synthesised in a two-step process involving the epoxidation of an alkene and a subsequent carboxylation to the cyclic carbonate. To couple both steps into a direct oxidative carboxylation reaction would be desired from an economical view point since additional work-up procedures can be avoided. Furthermore, the efficient sequestration of CO2, a major greenhouse gas, would also be highly desirable. In this work, the oxidative carboxylation of 1-decene is investigated using supported gold catalysts for the epoxidation step and tetrabutylammonium bromide in combination with zinc bromide for the cycloaddition of carbon dioxide in the second step. The compatibility of the catalysts for both steps is explored and a detailed study of catalyst deactivation using X-ray photoelectron spectroscopy and scanning electron microscopy is reported. Promising selectivity of the 1,2-decylene carbonate is observed using a one-pot two-step approach

The effect of ring size on the selective carboxylation of cycloalkene oxides

Carbon dioxide utilisation technology can contribute to the reduction of atmospheric CO2 levels both through its sequestration from flue gases and indirectly by relieving pressure on conventional feedstocks in chemical manufacturing. A promising approach is to employ CO2 to produce valuable cyclic carbonates (CCs) in reaction with suitable epoxides. This also has the advantage that carbon dioxide replaces toxic and hazardous reactants such as phosgene. In earlier work we have investigated the synthesis of epoxides from cycloalkenes using supported gold and gold–palladium nanoparticles as catalysts and oxygen from air as the oxidant under solvent free conditions. A strong dependence of epoxide selectivity on ring size was observed with C5 < C6 < C7 ≪ C8. In this study we extend this work to the investigation of cycloaddition of CO2 to different cycloalkene oxides with the ultimate aim of designing a process in which both epoxidation of an alkene and incorporation of CO2 could be achieved in a single process. However, we have found the opposite trend for the selectivity to carbonates: smaller ring cycloalkene oxides giving the highest carbonate selectivities while large rings do not yield CCs at all. The product distributions suggest that an alternative ring opening of the epoxides to yield alcohols and ketones is preferred under all the experimental conditions explored for larger ring systems. Additionally, the mechanism of the CC synthesis using a quaternary ammonium salt and ZnBr2 as the catalyst system was investigated using DFT methods. The results of the calculations support the experimental findings

Peganum Harmala plant as an adsorbent for the removal of Copper(II) ions from water

Batch removal of Cu(II) from water by powdered seeds of Peganum Harmala has been investigated in this research. The Peganum Harmala seeds were collected after which they have been beaten slowly, separated and then cleaned using a sieve. The prepared sorption is characterized by FT-IR. Batch adsorption studies have been undertaken in 100 ml Erlenmeyer flasks, inside an incubator container. The main process parameters that are considered are pH, contact time, Cu(II) concentration, the Adsorbent dose effect and reaction temperature effect. Cu(II) is measured at a wavelength of 620 nm, using a UV-vis spectrophotometer. The result evidence that the maximum removal of Cu(II) is observed at pH 6.2, with the pH over 6.2 result to participate the copper hydroxide. Clearly, the uptake process of the Cu(II) ion occurres very swiftly from the outset of the experiments during the first 15 min, after which there is a low decrease until 40 min, when maximum adsorption of Cu(II) ion onto Peganum Harmala is observed. An increased Cu(II) ions removal percentage occurres with increasing dose of adsorbents, increasing from 0.2 to 0.6 g followed by an increased percentage removal from 63.50% to 66.02%. Subsequently, the removal of Cu(II) ions decline, with an increased dose to 1g. Langmuir adsorption isotherm is more appropriate than the Freundlich adsorption isotherm, while the pseudo second-order reaction model is suitable for adsorption of the Copper ion onto the active centers of the Peganum Harmala surface compared with the pseudo first-order model

GRAPHICAL ONE-TIME PASSWORD AUTHENTICATION

Complying with a security policy often requires users to create long and complex passwords to protect their accounts. However, remembering such passwords appears difficult for many and may lead to insecure practices, such as choosing weak passwords or writing them down. One-Time Passwords (OTPs) aim to overcome such problems; however, most implemented OTP techniques require special hardware, which not only adds costs, but also raises issues regarding availability. This type of authentication mechanism is mostly adopted by online banking systems to secure their clients’ accounts. However, carrying around authentication tokens was found to be an inconvenient experience for many customers. Not only the inconvenience, but if the token was unavailable, for any reason, this would prevent customers from accessing their accounts securely. In contrast, there is the potential to use graphical passwords as an alternative authentication mechanism designed to aid memorability and ease of use. The idea of this research is to combine the usability of recognition-based and draw-based graphical passwords with the security of OTP. A new multi-level user-authentication solution known as: Graphical One-Time Password (GOTPass) was proposed and empirically evaluated in terms of usability and security aspects. The usability experiment was conducted during three separate sessions, which took place over five weeks, to assess the efficiency, effectiveness, memorability and user satisfaction of the new scheme. The results showed that users were able to easily create and enter their credentials as well as remember them over time. Eighty-one participants carried out a total of 1,302 login attempts with a 93% success rate and an average login time of 24.5 seconds. With regard to the security evaluation, the research simulated three common types of graphical password attacks (guessing, intersection, and shoulder-surfing). The participants’ task was to act as attackers to try to break into the system. The GOTPass scheme showed a high resistance capability against the attacks, as only 3.3% of the 690 total attempts succeeded in compromising the system.King Abdulaziz City for Science and Technolog