Fighting internet fraud: anti-phishing effectiveness for phishing websites detection

Recently, the Internet has become a very important medium of communication. Many people go online and conduct a wide range of business. They can sell and buy goods, perform different banking activities and even participate in political and social elections by casting a vote online. The parties involved in any transaction never need to meet and a buyer can sometimes be dealing with a fraudulent business that does not actually exist. So, security for conducting businesses online is vital and critical. All security-critical applications (e.g. online banking login pages) that are accessed using the Internet are at the risk of fraud. A common risk comes from so-called Phishing websites, which have become a problem for online banking and e-commerce users. Phishing websites attempt to trick people into revealing their sensitive personal and security information in order for the fraudster to access their accounts. They use websites that look similar to those of legitimate organizations and exploit the end-user's lack of knowledge of web browser clues and security indicators. This thesis addresses the effectiveness of Phishing website detection. It reviews existing anti-Phishing approaches and then makes the following contributions. First of all, the research in this thesis evaluates the effectiveness of the current most common users' tips for detecting Phishing websites. A novel effectiveness criteria is proposed and used to examine every tip and rank it based on its effectiveness score, thus revealing the most effective tips to enable users to detect Phishing attacks. The most effective tips can then be used by anti-Phishing training approaches. Secondly, this thesis proposes a novel Anti-Phishing Approach that uses Training Intervention for Phishing Websites' Detection (APTIPWD) and shows that it can be easily implemented. Thirdly, the effectiveness of the New Approach (APTIPWD) is evaluated using a set of user experiments showing that it is more effective in helping users distinguish between legitimate and Phishing websites than the Old Approach of sending anti-Phishing tips by email. The experiments also address the issues of the effects of technical ability and Phishing knowledge on Phishing websites' detection. The results of the investigation show that technical ability has no effect whereas Phishing knowledge has a positive effect on Phishing website detection. Thus, there is need to ensure that, regardless their technical ability level (expert or non-expert), the participants do not know about Phishing before they evaluate the effectiveness of a new anti-Phishing approach. This thesis then evaluates the anti-Phishing knowledge retention of the New Approach users and compares it with the knowledge retention of users who are sent anti-Phishing tips by email

Comparison of physiological and metabolic changes between phosphine resistant and susceptible strains of Rhyzopertha dominica (Fabricius) and Tribolium castaneum (Herbst)

The lesser grain borer, Rhyzopertha dominica (Fabricius) and the red flour beetle, Tribolium castaneum (Herbst) are serious insect pests of stored grain and a broad range of other stored products. Phosphine is widely used as a fumigant to protect the stored commodity from insect damage. However, phosphine resistance by stored grain insects has been occurred worldwide. The mechanism of phosphine resistance reported that it might include changes in respiratory and metabolic function. Lower respiration of the resistant insects may reduce the rate of phosphine entering insect bodies. Changes in the metabolism of resistant strain insects may prevent metabolic crises or supplies more energy. In this thesis, the respiration rate, the emission of VOCs and lipid content of phosphine susceptible and resistant strains of R. dominica and T. castaneum were investigated. Two novel methods have been explored and validated, including the headspace solid phase microextraction (HS-SPME) and direct immersion solid phase microextraction (DI-SPME) technologies. The optimal conditions for both methods were investigated, and the optimized conditions were used for our study to determine the volatile organic compounds (VOCs) from insects and the insect cuticular hydrocarbons. This thesis has confirmed that the respiration rate of the susceptible strain insects was significantly higher than the resistant strains. Phosphine can reduce the respiration rate of both susceptible and resistant strains when treated with average concentrations ranged from 2 to 20 ppm. However, the rate of respiration of the resistant strains was unexpectedly increased under a high level of phosphine (320 ppm) which indicated that resistant strain insect metabolism was elevated. Moreover, two characteristics were used as indicators to determine the metabolic differences between phosphine susceptible and resistant strains of R. dominica and T. castaneum including VOCs and lipid contents. The GC-MS response of most of the VOCs detected in susceptible strains of both species used in this study were higher than that from the resistant strains. However, 2, 3-Butanediol, [R-(R*, R*)] was significantly in abundance in the resistant strain of R. dominica; while dodecanal was only detected from the susceptible strain of T. castaneum. Lipid contents including cuticular hydrocarbons, glycerolipids and phospholipids were analysed with different methods, such as cuticular hydrocarbons were analysed using our optimized (DI-SPME) method; glycerolipids and phospholipids were determined by HPLC. The results showed that resistant strains of both insect species containing higher levels of lipids than the susceptible insects. This higher content of lipids may have significant role in phosphine resistance. This study concludes that respiration rate was found higher in the susceptible strain than the resistant; however, treating the resistant strain with a high concentration of phosphine caused an increase in the rate of the respiration. Some VOCs were found significantly different which indicated that metabolism is different according to the susceptibility of the strains. 2,3-Butanediol, [R- (R*, R*)] and dodecanal were suggested to be used as a biomarker to differentiate susceptible and resistant strains of R. dominica and T. castaneum respectively. The resistant insects of both species used in this study had a higher amount of lipids than the susceptible insects, shows that the higher lipid contents in the resistant strains may prevent the fumigant from entering the insect bodies, provide energy to the insect and participate in avoiding phosphine effect

Preliminary study on the differences in hydrocarbons between phosphine-susceptible and -resistant strains of Rhyzopertha dominica (Fabricius) and Tribolium castaneum (Herbst) using direct immersion solid-phase microextraction coupled with GC-MS

Phosphine resistance is a worldwide issue threatening the grain industry. The cuticles of insects are covered with a layer of lipids, which protect insect bodies from the harmful effects of pesticides. The main components of the cuticular lipids are hydrocarbon compounds. In this research, phosphine-resistant and -susceptible strains of two main stored-grain insects, T. castaneum and R. dominica, were tested to determine the possible role of their cuticular hydrocarbons in phosphine resistance. Direct immersion solid-phase microextraction followed by gas chromatography-mass spectrometry (GC-MS) was applied to extract and analyze the cuticular hydrocarbons. The results showed significant differences between the resistant and susceptible strains regarding the cuticular hydrocarbons that were investigated. The resistant insects of both species contained higher amounts than the susceptible insects for the majority of the hydrocarbons, sixteen from cuticular extraction and nineteen from the homogenized body extraction for T. castaneum and eighteen from cuticular extraction and twenty-one from the homogenized body extraction for R. dominica. 3-methylnonacosane and 2-methylheptacosane had the highest significant difference between the susceptible and resistant strains of T. castaneum from the cuticle and the homogenized body, respectively. Unknown5 from the cuticle and 3-methylhentriacontane from the homogenized body recorded the highest significant differences in R. dominica. The higher hydrocarbon content is a key factor in eliminating phosphine from entering resistant insect bodies, acting as a barrier between insects and the surrounding phosphine environment

Adaptation of Federated Explainable Artificial Intelligence for Efficient and Secure E-Healthcare Systems

Explainable Artificial Intelligence (XAI) has an advanced feature to enhance the decision-making feature and improve the rule-based technique by using more advanced Machine Learning (ML) and Deep Learning (DL) based algorithms. In this paper, we chose e-healthcare systems for efficient decision-making and data classification, especially in data security, data handling, diagnostics, laboratories, and decision-making. Federated Machine Learning (FML) is a new and advanced technology that helps to maintain privacy for Personal Health Records (PHR) and handle a large amount of medical data effectively. In this context, XAI, along with FML, increases efficiency and improves the security of e-healthcare systems. The experiments show efficient system performance by implementing a federated averaging algorithm on an open-source Federated Learning (FL) platform. The experimental evaluation demonstrates the accuracy rate by taking epochs size 5, batch size 16, and the number of clients 5, which shows a higher accuracy rate (19, 104). We conclude the paper by discussing the existing gaps and future work in an e-healthcare system

Role of lipids in phosphine resistant stored-grain insect pests Tribolium castaneum and Rhyzopertha dominica

Insects rely on lipids as an energy source to perform various activities, such as growth, flight, diapause, and metamorphosis. This study evaluated the role of lipids in phosphine resistance by stored-grain insects. Phosphine resistant and susceptible strains of the two main stored-grain insects, Tribolium castaneum and Rhyzopertha dominica, were analyzed using liquid chromatography-mass spectroscopy (LC-MS) to determine their lipid contents. Phosphine resistant strains of both species had a higher amount of lipids than susceptible stains. Significant variance ratios between the resistant and susceptible strains of T. castaneum were observed for glycerolipids (1.13- to 53.10-fold) and phospholipids (1.05- to 20.00-fold). Significant variance ratios between the resistant and susceptible strains of R. dominica for glycerolipids were 1.04- to 31.50-fold and for phospholipids were 1.04- to 10.10-fold. Glycerolipids are reservoirs to face the long-term energy shortage. Phospholipids act as a barrier to isolate the cells from the surrounding environment and allow each cell to perform its specific function. Thus, lipids offer a consistent energy source for the resistant insect to survive under the stress of phosphine fumigation and provide a suitable environment to protect the mitochondria from phosphine. Hence, it was proposed through this study that the lipid content of phosphine-resistant and phosphine-susceptible strains of T. castaneum and R. dominica could play an important role in the resistance of phosphine

New method of analysis of lipids in Tribolium castaneum (Herbst) and Rhyzopertha dominica (Fabricius) insects by direct immersion solid-phase microextraction (DI-SPME) coupled with GC–MS

Lipids play an essential role in providing energy and other physiological functions for insects. Therefore, it is important to determine the composition of insect lipids from cuticular and internal tissues for a better understanding of insect biology and physiology. A novel non-derivatization method for the analysis of lipids including fatty acids, hydrocarbon waxes, sterols in Tribolium castaneum (Herbst) and Rhyzopertha dominica (Fabricius) was explored using the direct immersion solid-phase microextraction (DI-SPME) coupled with gas chromatography–mass spectrometry (GC–MS). Nine extraction solvents, acetonitrile, methanol, hexane, ethanol, chloroform, acetonitrile and ethanol (1:1 v/v), acetonitrile and water (1:1 v/v), ethanol and water (1:1 v/v) and acetonitrile and ethanol and water (2:2:1 v/v/v) were selected and evaluated for the extraction of insect lipids with DI-SPME fiber. Acetonitrile extraction offered the best qualitative, quantitative, and number of lipids extracted from insects samples results. Acetonitrile extracted high-boiling point compounds from both species of tested insects. The range of hydrocarbons was C25 (pentacosane) to C32 (dotriacontane) for T. castaneum and C26 (11-methylpentacosane) to C34 (tetratriacontane) for R. dominica. The major compounds extracted from the cuticular surface of T. castaneum were 11-methylheptacosane (20.71%) and 3-methylheptacosane (12.37%), and from R. dominica were 10-methyldotriacontane (14.0%), and 15-methyltritriacontane (9.93%). The limit of detection (LOD) for the n-alkane compounds ranged between 0.08 (nonacosane) and 0.26 (dotriacontane) µg/g and for the fatty acids between 0.65 (arachidic acid) to 0.89 (oleic acid) µg/g. The study indicated that DI-SPME GC–MS is a highly efficient extraction and a sensitive analytical method for the determination of non-derivatized insect lipids in cuticular and homogenized body tissues

Numerical study of MEMS-Based vaporizing liquid microthruster for CubeSats

In the last decade, the interest in CubeSat had been increased dramatically. The low deployment cost and the capability to operate in low Earth orbit enable it to become one of the most attractive tools for different space missions such as remote sensing and communications. However, the information about the technology of the CubeSat in terms of the design and the propulsion system is still limited or characterized as classified data. The focus of this work is mainly on the enhancement of the performance of the vaporizing liquid microthruster (VLM) propulsion system of a CubeSat. The development in propulsion systems' miniaturization has generated a proliferation entailing both nano- and microsatellite designs. Consequently, the microelectromechanical systems (MEMS) technology has diversified into various applications. Recently, MEMS have been applied in the domain of micropropulsion for miniaturized satellites. The VLM is amongst several MEMS microthrusters which is established newly, has gained research attention for its capability to produce continuously variable thrust in the micronewton (µN) to millinewton (mN) range. In this thesis, 3D model simulations were conducted to numerically investigate the fluid flow behaviour of MEMS-VLM thruster with the aid of the Computational Fluid Dynamics (CFD) technique. The computational domain consists of an inlet channel, distributer, microchannels, chamber and in-plane converging-diverging (C-D) nozzle. The geometry's modification aims to achieve maximum thrust force by controlling the VLM chamber heating power at a constant inlet propellant flow rate. The computational simulations of the proposed design were performed for two phases: subsonic section (inlet-distributor-microchannel-chamber) and supersonic section (planar convergent-divergent micronozzle). The numerical results demonstrate a 38% increase in the thrust force and a 22% decrease in the heating power compared to the design proposed by Kundu et al. [Pijus Kundu et al. 2012 J. Micromech. Microeng. 22 025016]. In conclusion, the geometrical modification remarkably increases the underlying thrust with comparatively low input power. The proposed VLM modification can yield up to 1.38 mN thrust and a specific impulse of 70 s by utilizing 2 W heating power at a 2 mg/s water flow rate, which is within the capability of the CubeSat power budget and fuel amount. Moreover, the current design could reduce the possibility of propellant pumps failure that resulted from the boiling of the water within the inlet part of the VLM, and hens reduce the thrust instability. Finally, a comparative evaluation with other published VLM research shows that the current design can produce relatively more thrust force by utilizing less input power

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