United Arab Emirates University
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USING SMART CONTRACTS IN THE FINANCIAL STOCK MARKET: AN ANALYTICAL STUDY
Get PDFSmart contracts are considered one of the latest technologies that have obtained attention from many Legalists and Engineers. Smart contracts are a set of arrangements written via programming languages through computer programs or by programmers without the need for an intermediary. Smart contracts are self-executing. It executes once the terms and conditions agreed between the parties happen. Perspectives differ among legalists about the legality of smart contracts. Some legalists consider these contracts as binding legal contracts, while others believe that a smart contract might be just a part of a traditional contract. On the other hand, some legalists question their entire legal nature. This study focuses on whether these contracts are legal and binding and the possibility of using these contracts in the UAE stock market. This study discussed the nature, characteristics, advantages, limitations, and applications of smart contracts. Moreover, this study shows the possibility of applying the general rules of contracts and obligations and some special laws on these contracts
PRICING ASIAN OPTIONS DURING CRISES WITH THE IMPACT OF EXOGENOUS EVENTS
Get PDFAsian options are path-dependent options since their payoff is built on the prices of the underlying asset over a time period. The Asian option pricing problem is primarily subject to the prediction model for asset prices. The pioneer Black Scholes paper suggests a GBM- Geometric Brownian motion. The Black-Scholes formula suffers from several shortcomings. For instance, the GBM does not take into consideration crises. Another problem with the Black-Scholes model is that it does not deal with the impact of external events. This work aims at a suggested model that encompasses the impacts of crises and external events together. It is based mainly on models with crises and models with an external event impact. The underlying asset is then driven by a stochastic differential equation with a modulated Markov GBM and an increase in volatility. Determining the price of an Asian option will be explored under a suggested model. Moreover, numerical techniques will be employed to get a numerical solution and to simulate trajectories for the prices of the options and the underlying asset
VALORIZATION OF THE POLYMERIC CONSTITUENTS IN PLASTIC WASTES THROUGH THERMO-CHEMICAL PROCESSES BY USING VIABLE METAL OXIDES ADDITIVES
Get PDFThe rapid accumulation of different types of plastic waste necessitates the development of effective and economically viable waste management operations. Such a process should ideally not only mitigate associated environmental burdens but also recycle and recover value-added products. Through incineration or pyrolysis, thermal processing has emerged as a mainstream approach to waste management of the ever-increasing loads of different categorized plastic wastes. Throughout the work of the thesis, we have utilized a multitude of complementary techniques spanning material characterizations, catalysis, kinetic modelling, and density functional theory (DFT) to comprehend the complex chemistry that underpins catalytic chemical recycling of plastic wastes. Effective chemical recycling of halogencontaminated plastic wastes entails the removal of HCl and HBr by fixation of the halogen content and the subsequent production of pure hydrocarbon streams. Such scenarios apply to chemical recycling of the polymeric fraction in e-waste, medical waste and other plastic wastes that typically contain high loads of organic bromine and chlorine in the form of BFRs and PVC; respectively. Driven by the unprecedented accumulation of facemasks during the Covid-19 era, we commenced the project by exploring catalytic upgrading of the various polymeric fractions in the facemasks. Thus, we investigated the upgrading of fragments from the facemasks over niobium-doped CeO2 catalysts under oxidative and pyrolytic conditions. We found that the process to convert alkyl chain polymers into methylated benzenes compounds; could be utilized as transportation fuels. In the second project, we found that the co-pyrolysis of PVC with metal oxides (MO’s) at temperatures between 300 and 500°C resulted in the production of metallic chlorides. PVC with ZnO mixture captured 91.13% of the emitted HCl, whereas ZnFe2O4 and NiZnFe4O4 seized the HCl emission to 65.78% and 83.56%, respectively. During the pyrolysis reaction, Lewis acids such as ZnCl2, FeCl2, and NiCl2 were formed which triggered the isomerization of cis to trans olefins that made it less favorable to undergo cyclization reactions. As such significant depreciation in the formation of benzene derivatives and poly aromatic hydrocarbons was revealed by GCMS with the inclusion of MO’s, whereas it enhanced the formation of alkanes. The chemical component in the non-metallic fraction in e-waste, most of the bromine content is emitted as inorganic bromine in the form of HBr. HBr is emitted in appreciable quantities during the thermal decomposition of printed circuit board; PCB. The latter contains ~ 4% BFRs by weight. The highly corrosive, yet relatively reactive HBr, renders recovery of bromine-free hydrocarbon streams from brominated polymers in PCBs which is very challenging. Via an integrated experimentalsimulation formalism, the co-pyrolysis of PCB with Al2O3 explores the potential of deploying alumina oxide as a debromination agent of Brcontaining hydrocarbon fractions in PCBs. An experimental setup was designed on a lab scale using a flow reactor to carry out the pyrolysis and oxidation reaction of PCBs and different BFRs. TBP (Tri bromophenol) is utilized as a model compound of BFRs as their most common formulations include brominated phenolic rings. Co-pyrolysis of hematite with TBP entails a rather low cracking capacity under pyrolytic conditions. Analysis of condensate products indicates that oxidative degradation of a gaseous stream of TBP results mainly in the formation of brominated alkanes such as bromoethane and bromo-pentane. Likewise, Ion chromatography (IC) measurements disclosed a noticeable reduction in the concentrations of escaped HBr. Transformation of iron oxides into iron bromides (FeBr2) during pyrolysis and combustion operations is evident through XRD measurements. The co-pyrolysis of tetrabromobisphenol A (TBBA; as another model compound for the bromine content in Waste PCBs) with calcium hydroxide (Ca(OH)2) made conclusive evidence in a complete fixation of the bromine content and produces bromine-free pyrolysis oil. For instance, measurements by IC and FTIR (gas sampling cell) confirm the disappearance of HBr from the gaseous stream during co-pyrolysis of a TBBA:Ca(OH)2 mixture between 200-500 oC. Likewise, no brominated compounds could be detected from the analysis of the condensate and gas fractions. As the collected oil is dominated by n-alkanes, it is concluded that Ca(OH)2 displays both cracking and debromination capacity. DFT calculations map out important reaction pathways that operate in the initial degradation of the TBP molecule, whereas for Ca(OH)2 and TBBA mixture, the reaction pathways for the transformation of Ca(OH)2 into CaBr2 via dissociative addition of HBr molecules were also investigated. Here we also report the potentiality of producing value-added products from the polymeric wastes using the GCMS by virtue of catalytic pyrolysis, co-pyrolysis, and oxidation of the considered waste materials. The thermo kinetic parameters are derived for the TBP and TBBA incorporated with hematite and Ca(OH)2 by using the model-free (CoatsRedfern) and model fitting (KAS, FWO, and Starink models) approaches from the thermogravimetric analysis data (TGA). Obtained profiles infer that the addition of hematite to TBP systematically reduces the governing activation energy (Ea) in both thermochemical processes compared to neat TBP. The computed Ea values for the pyrolytic decomposition of pure TBBA and its mixture with Ca(OH)2 reside in the narrow ranges of 111.7-112.1 kJ/mol and 62.8-63.4 kJ/mol, respectively. The results obtained from the kinetic parameters find direct application in reactor modeling (rotary kiln) and heat transfer design in domains related to the recycling of e-waste. Outcomes from the project are expected to pave the way toward the commercialization of a continuous chemical recycling process of polymeric waste that is based on the use of affordable additives. The project taps into optimizing a zero-emission route that could accommodate the treatment of polymeric wastes (masks, PVC, and e-waste) within the context of a waste-to-energy approach that has been recently implemented in the UAE targeting UN SDG 12. Fundamental and applied knowledge to be attained in this research are instrumental in the pursuit of closing the gap in the circular economy strategy of polymeric waste in general
PHYSIOCHEMICAL CHARACTERIZATION AND IN-VITRO INVESTIGATION OF THE EFFECT OF COMMERCIAL AND NOVEL NON-DIGESTIBLE FIBER/PREBIOTICS ON THE GROWTH OF PROBIOTICS
Get PDFProbiotics and prebiotics play a major role in enhancing the gut microbiota and, consequently, human health. Non-digestible dietary fibers (prebiotics) are selectively fermented and induce specific changes in the composition and/or activity of the gastrointestinal microbiota (probiotics), thus conferring benefit(s) upon the host\u27s health. The consumption of prebiotic products has been extended from diet supplementation to clinical application in various health complications, emerging as a potential therapeutic to manipulate several diseases. Different pharmaceutical companies normally use a blend of many fibers from various sources to prepare commercial prebiotic products. Currently, no data is available to what extent the components of prebiotic supplements are non-digestible by humans and fermentable by healthy gut microbial populations for their growth to maintain host health. Hence, the main objective of this thesis was to evaluate the effect of commercial and novel fibers on the growth of probiotics (beneficial gut microorganisms) isolated in the lab from commercial probiotics-containing products (yogurt Y strain, and probiotic sachet S strain) and bacterial consortium of 6 most abundant gut strains in aerobic and anaerobic conditions. The metabolism/fermentation of prebiotics has been evaluated using the TLC method, and the metabolite produced by different probiotics using different fiber blends under different growth conditions has also been assessed. Furthermore, the antimicrobial and antioxidant activities of metabolites were evaluated to map the biological role of gut metabolites in the host. Different microbial strains selectively utilized fiber supplements and produced a very interesting metabolic profile with significant differences in types and amounts of metabolites under aerobic and anaerobic growth conditions. Metabolites produced under anaerobic conditions showed a drop in pH and high biological activities as compared to the metabolites produced under aerobic conditions by the same microorganisms. Our results show that levan should also be added in commercial blends as it not only enhances gut microbial growth but also results in the production of bioactive metabolites after fermentation. The primary issue was the lack of an anaerobic facility, which limited our work to the analysis of 3 commercial blends under anaerobic conditions. So, for future studies, all prebiotic samples will be tested anaerobically, and metabolites will be identified using GC-MS, LC-MS, and HPLC. Their biological activities, like antioxidant and immunomodulation in vitro using cell lines and in vivo using mouse models, will also be evaluated
AUTOMATING MODULAR CONSTRUCTION MANUFACTURING FOR AFFORDABLE HOUSING
Get PDFIn recent years, there has been an increase in the frequency and intensity of natural disasters worldwide, resulting in loss of life, displacement, and extensive property damage. According to the UNHCR\u27s report, 89.3 million individuals were displaced in 2021, highlighting that the speed and volume of displacement exceeds the availability of solutions for those affected. To address the urgent need for affordable housing solutions, modular construction is preferred over traditional construction methods as it tackles limitations such as long project durations, high costs, and safety and environmental concerns. Integrating advanced technologies in modular construction can further enhance its benefits and address design, manufacturing, and assembly challenges. Although researchers studied automation integration in construction, research on the effectiveness of such integration in the context of modular affordable housing is limited. This study examines the impact of automation on the time efficiency and cost of the modular construction manufacturing process, ultimately enhancing affordable housing production. The research follows a mixed-methods approach, combining both quantitative and qualitative methods. Data will first be collected through a literature review to investigate the current state of automation technology integration in modular construction, and second, simulation tools will be used to evaluate the feasibility and effectiveness of integrating automation in modular affordable housing construction. The 3D simulation will compare automated and manual assembly processes, focusing on resource utilization, time savings, and cost implications. Results indicated that automated processes outperformed manual methods in terms of speed, leading to significant time reductions of about 37% and long-term cost savings, estimated at 535,000 USD annually, despite the higher upfront investment, which could be returned in about 6 months. By conducting a detailed analysis, this research provides insights into optimizing the construction process by integrating automation into modular construction manufacturing. Also, it addresses the gap by quantitatively comparing manual and automated modular construction manufacturing processes using 3D simulation
Judicial Individualization of Punishment in UAE Criminal Law
Get PDFThis study addresses the topic of judicial individualization of punishment in UAE criminal legislation through a descriptive-analytical approach. In the preliminary section, the study defines punishment, which is imposed as a consequence of a crime that has already occurred, and precautionary measures aimed at confronting criminal danger to prevent future harm that could affect society. The characteristics and purposes of both punishment and precautionary measures are detailed, as they cannot be applied unless those implementing them understand their goals and intended outcomes. The study examines, in the first chapter, the concept of legislative and judicial individualization of punishment, where the former precedes and influences the latter. It also discusses the methods of judicial individualization, including primary and alternative punishments, such as deportation and community service, which the judge may select based on the type of crime. The study then explores the quantitative gradation of these punishments and their various types. The first chapter concludes with the powers granted to the judge by the criminal legislator, including legal excuses, mitigating circumstances, aggravating circumstances, recidivism, repetition of offenses, suspension of execution, and judicial pardon. These are all provided by the legislator, acknowledging the importance of judicial individualization of punishment.In the second chapter, the study explores the criteria for judicial individualization of punishment, which include personal factors related to the offender and objective factors related to the crime and the punishment. These factors cannot be fully addressed by legislative individualization, as legal texts are characterized by their generality and abstraction, and they cannot predict the circumstances surrounding these elements. The study also highlights the role of the public prosecution in the judicial individualization of punishment, noting that the prosecution is a branch of the judiciary. It holds the authority to issue penal orders, dismiss criminal cases due to lack of importance, supervise judicial officers, and pursue criminal cases. The second chapter concludes with practical applications related to the judicial individualization of punishment. The study reached several conclusions, the most important of which is that the characteristics and purposes of punishment cannot be achieved without individualizing it for each person according to the nature of the crime, its circumstances, and the personality of the accused. Furthermore, the UAE criminal legislator has not stipulated clear guidelines or criteria for judicially determining punishments. The absence of such guidelines leads to the issuance of sentences that do not align with the crime or the criminal. This lack of reasoning in judgments, especially when increasing or decreasing the punishment beyond its minimum or maximum limits or when using any of the available alternatives to the judge, results in the misuse of these methods and makes it difficult to monitor their application.One of the main recommendations of the study is the need to enact provisions requiring judges to individualize punishment judicially. Additionally, there is a need to establish guiding criteria for judges to determine punishments, as is the case in Yemeni legislation. The study also emphasizes the importance of enacting provisions requiring reasoning when increasing or decreasing punishment beyond its minimum or maximum limits or when using any of the alternatives available to the judge
HUMAN RESOURCE PRACTICES AND EMPLOYEE OUTCOMES: AN EXAMINATION OF PERFORMANCE, SATISFACTION AND DIVERSITY CLIMATE IN THE HOSPITALITY SECTOR OF SAUDI ARABIA
Get PDFTourism and related industries have become essential economic activities that play a significant role in the development, prosperity, and well-being of a country. The tourism and hotel sector in the Kingdom of Saudi Arabia (KSA) is currently undergoing significant development to diversify the national economy in line with the KSA Economic Vision 2030 Initiative. To align this sector with international standards in terms of job satisfaction and performance, human resource management practices (HRMPs) play a key role in determining the job satisfaction of employees in their various work environments. HRMPs include various job-related activities, training and development (T+D) programs, rewards, performance management, and promoting participation. The main focus of HRMPs is, therefore, to develop employees and create a positive work environment. Although there is active academic research worldwide on the potential relationship between HRMPs and employee performance, little has been written about this relationship in the Saudi hotel industry. This study examines the relationship between four HRMPs and job performance of employees based on job satisfaction, particularly attention to the impact of different work climates. A quantitative research design was used to obtain data from hotel sector managers in the KSA. Probability sampling was used to collect data from four cities in Saudi Arabia. Data was collected from 700 participants using a questionnaire. In addition, the structural equation modeling (SEM) technique was used to test the validity of the study\u27s measurement and structural model using SMART-PLS. The measurement model of SEM confirmed the reliability and validity. The obtained results showed that HRMPs have a positive relationship with employee job satisfaction and performance. Furthermore, employee job satisfaction moderates the relationship between HRMPs and employee job performance, while diversity climate also plays an important moderating role in this relationship. The current study contributes to social exchange theory (SET). The practical implications are that the HRM managers in the hotel industry will gain insights from this study about the positive impact of HRMPs on employee job satisfaction and performance in the KSA hotel industry
FAST AND RELIABLE AUTHENTICATION METHOD FOR INDOOR CONSTRAINED DRONES
No full textOver the last twenty years, the commercial sector of Unmanned Aerial Vehicles has been growing exponentially, owing to their rapid deployment, high mobility, and the number of applications in the industry field such as military, transportation, critical infrastructures, as well as in the academic field for research purposes. One of the main communication systems adopted by the UAVs relies on transmitting wireless signals.
In particular, UAVs are adopted for indoor use-case scenarios, such as warehouse inventory applications and indoor building inspections. They need to transmit control messages and sensitive data by leveraging an efficient, short-range, and secure communication channel to avoid man-in-the-middle, spoofing, and hijacking attacks. This dissertation focused on investigating the security of very constrained unmanned aerial systems in IEEE 802.15.4 networks targeted for indoor domains.
In this thesis, we propose a new secure protocol based on the Bitwise Precomputable Message Authentication Code (BP-MAC) scheme to provide authenticity and integrity protection to the message payload. Further, we also propose a new frame design that can be encapsulated in the MAC layer of IEEE 802.15.4 networks to improve drone accountability in indoor scenarios. Combining the use of the BP-MAC scheme and our new IEEE 802.15.4 frame design for UAVs in indoor scenarios results in several benefits in terms of optimization, efficiency, and a reduction in the amount of exchanged data. We provide the results by simulating our proposed solution from the computational and networking perspective. The proposed solution is filling the security gap in the literature (e.g, UMAC) to effectively safeguard the communication of indoor drones. It demonstrates a significant improvement in terms of memory usage, bandwidth, energy savings due to reduced workload, and the ability to attain the same level of security offered by traditional authentication schemes by using lighter techniques. Within this work, we identify and address new security challenges for promising future research directions
THE ROLE OF TASK-BASED LANGUAGE ASSESSMENT IN ENGLISH LANGUAGE LEARNING AND LEARNER AUTONOMY ENHANCEMENT IN AN EFL HIGH SCHOOL CONTEXT IN THE UAE
No full textAssessment plays an integral role in education, incorporating various types that serve multiple purposes. In language education, the proper integration of formative assessment practices, such as Task-Based Language Assessment (TBLA), is crucial to improve students’ language learning. This study explores the impact of implementing TBLA in an English as a foreign language (EFL) high school context on language learning. It also investigates whether and to what extent TBLA application promotes Learner Autonomy (LA). Furthermore, this study examines the teacher’s and students’ perceptions of the intervention and its impact on linguistic and non-linguistic skills. The study used an experimental mixed methods design. First, it collected quantitative data through pre- and post-tests of the TBLA experiment. Then, qualitative data were collected through a students’ survey and teacher’s interview. The study recruited a total of 57 participants: 1 English teacher and 56 students in two Grade-10 classrooms, one designated as an experimental group (n = 27) and the other as a control group (n = 29). The study was conducted over a whole trimester in a private school, in Al Ain, a major city in the Abu Dhabi Emirate, capital of the United Arab Emirates (UAE). The treatment consisted of four TBLA tasks; each focused on one or more language skills (Reading, Writing, Listening, Speaking, and Usage) along with LA enhancement activities. The findings showed that TBLA was an efficient assessment practice for improving EFL learners’ overall language learning. Students’ achievements were enhanced at various levels. The total score and the Writing skill significantly improved in favor of the experimental group while the other skills (Listening, Reading, Speaking and Usage) showed noteworthy improvements, but not to a statistically significant level. In addition, the study confirmed previous findings as students expressed satisfaction with TBLA and interest in its formative assessment features and authentic topics. The students also reported that their autonomy was enhanced by TBLA tasks. Besides, the teacher commended the TBLA intervention and reported that it improved various aspects of learners’ linguistic and autonomous skills like reflection, self-regulation, and evaluation of self and others. This study is significant as it is the first to study TBLA and LA in an EFL high school context in the UAE and the wider Gulf region. Globally, several studies were conducted on TBLA application in different contexts. However, no previous research studied TBLA in EFL high school contexts. Similarly, there are no past studies investigating how TBLA contributes to LA enhancement as well as language learning. Moreover, this study yielded important theoretical and pedagogical implications. Mainly, the findings supported three major theoretical constructs: the Sociocultural Theory, TBLA, and LA. Based on the study findings, a number of pedagogical implications for L2 teachers, L2 students, curriculum developers, and program trainers were made. Finally, the study’s limitations and future research recommendations were listed, which pave the way for further research on TBLA and LA in the UAE EFL context and beyond
The Effect of Using Interactive Digital Story on Academic Achievement and Motivation Towards Learning Digital Skills
Get PDFThe purpose of this study was to investigate the effect of using interactive digital story on academic achievement and motivation in the digital skills course among first-level middle school students. The research population consisted of the first-level middle school students in the Sabia province in the second semester of 2022. A quasi-experimental approach was adopted with a sample size of 50 students from Al-Khalidiya School in Sabia; the control group consisted of 25 students who studied through the textbook, while the experimental group studied via interactive digital stories with the same sample size. Several interactive digital stories were designed as research material and were used with the experimental group. Two research tools were prepared: academic achievement test and motivation scale (MSLQ). The results suggested that the use of the interactive digital story in teaching had a positive effect on student academic achievement and motivation when learning of digital skills, The results showed a statistically significant difference (0.05) between the average grades of students in posttest in favor of the experimental group. Moreover, the results showed a statistically significant difference (0.05) between the average grades of students the motivation scale in favor of the experimental group.
Keywords: Digital skills education, computer education, interactive digital stories, motivation, educational attainment, middle school