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A Survey on the Integration of Blockchain With IoT to Enhance Performance and Eliminate Challenges
No full textInternet of things IoT is playing a remarkable role in the advancement of many fields such as healthcare, smart grids, supply chain management, etc. It also eases people's daily lives and enhances their interaction with each other as well as with their surroundings and the environment in a broader scope. IoT performs this role utilizing devices and sensors of different shapes and sizes ranging from small embedded sensors and wearable devices all the way to automated systems. However, IoT networks are growing in size, complexity, and number of connected devices. As a result, many challenges and problems arise such as security, authenticity, reliability, and scalability. Based on that and taking into account the anticipated evolution of the IoT, it is extremely vital not only to maintain but to increase confidence in and reliance on IoT systems by tackling the aforementioned issues. The emergence of blockchain opened the door to solve some challenges related to IoT networks. Blockchain characteristics such as security, transparency, reliability, and traceability make it the perfect candidate to improve IoT systems, solve their problems, and support their future expansion. This paper demonstrates the major challenges facing IoT systems and blockchain's proposed role in solving them. It also evaluates the position of current researches in the field of merging blockchain with IoT networks and the latest implementation stages. Additionally, it discusses the issues related to the IoT-blockchain integration itself. Finally, this research proposes an architectural design to integrate IoT with blockchain in two layers using dew and cloudlet computing. Our aim is to benefit from blockchain features and services to guarantee a decentralized data storage and processing and address security and anonymity challenges and achieve transparency and efficient authentication service
Targeting Breast Cancer Using Hyaluronic Acid-Conjugated Liposomes Triggered with Ultrasound
No full textThe successful targeting of tumors can be achieved by conjugating targeting moieties to nanoparticles. These modifications allow nannocarriers to achieve greater targeting specificity through binding to specific receptors overexpressed on the surface of the tumor cells. In this study, pegylated liposomes encapsulating the model drug/dye calcein and conjugated to hyaluronic acid (HA) molecules were successfully synthesized, and their ability to target HA receptors overexpressed on a breast cancer cell line was investigated in vitro. Low-frequency ultrasound (LFUS), applied at three different power densities (6.2, 9, and 10 mW/cm2) were used to trigger the release of the entrapped calcein. Both the control and HA-conjugated liposomes showed similar release profiles. HA conjugation to the liposomes resulted in a significant increase in calcein uptake by the breast cancer cell line MDA-MB-231 known for its CD44 (HA receptor) overexpression, while such an effect was not recorded with NIH-3T3, an embryonic mouse fibroblast, with low levels of CD44 expression. The application of low LFUS showed a significant enhancement of calcein uptake by MDA-MB-231 cells from our liposome compared to calcein uptake without cell exposure to ultrasound. These findings suggest that combining HA-conjugated liposomes with ultrasound is a promising drug delivery platform in breast cancer treatment
A Holistic Intersection Rating System (HIRS)—A Novel Methodology to Measure the Holistic Operational Performance of Signalized Urban Intersections
No full textSignalized urban intersections are key components of urban transportation networks. They are traditionally viewed and designed as primarily motorized traffic facilities, and thus their physical and operational designs have traditionally aimed at maximizing traffic throughput subject to constraints dictated by vehicular safety requirements and pedestrian crossing needs. Seen from a holistic viewpoint, urban intersections are hubs or effective centers of community activities of which traffic flow is only one. Those hubs have direct and indirect impacts on the overlapping traffic functionalities, the environment, public health, community wellbeing, and the local economy. This study proposes a new rating system, the Holistic Intersection Rating System (HIRS), aimed at appraising signalized intersections from a more inclusive viewpoint. This appraisal covers traffic functionality, sustainability, and public health and community wellbeing. This rating system can be used as a guide to conceive, plan, or design new intersections or revamp existing ones. HIRS rates signalized urban intersections based on the level of use of relevant enabling technologies, and the physical and operational designs that allow those intersections to operate holistically, thus leading to a more human-centric and sustainable operational performance. HIRS was validated using a panel of experts in construction, transportation, and public health. The Relative Importance Index (RII) method was used to weigh the HIRS features. The rating system was piloted on a sample of 20 intersections in different cities in the UAE. The results revealed glaring gaps in services to or the consideration of pedestrians, cyclists, and nearby households. The sample intersections scored a mean of 32% on the public health and community wellbeing section, 37% on the pedestrian subsection, and 15% on the cyclist subsection. Such relatively low scores serve as indicators of areas for improvements, and if mapped to their specific features and their relative weights, specific physical and operations designs and technology integration can be identified as actionable items for inclusion in plans and/or designs
Addressing Issues and Challenges in Managing Migratory Tuna Resources in the Western and Central Pacific Ocean
No full textTuna resources in the Western and Central Pacific Ocean are the world’s largest and most valuable fisheries of their type and are vital to the economy and the sustainable development of the region. However, the region witnesses a rapid decline in tuna resources and the depletion of species such as bigeye and yellowfin tunas, and overharvesting of the other species. This study investigated the collaborative management model used to manage migratory tuna resources. The study followed a case study design with a focus on the Western and Central Pacific Ocean Fisheries Commission. Forty interviews were conducted with key stakeholders. The findings indicated that six factors, namely, structure and size, self-interest, self-enforcement, leadership style, equality of power, and culture, affected significantly the outcomes of a collaborative management model. The findings also provide important insights on how the factors influenced the outcomes. The study contributes to a better understanding of international governance of common-pool resources (CPRs) and its challenges, and thus helps policymakers develop strategies for managing migratory fishing resources for the sake of economic viability and sustainability in the region
Physicochemical Characterization and Seasonal Variations of PM10 Aerosols in a Harsh Environment
No full textWe have conducted a comprehensive sampling campaign of PM₁₀ pollutants at a site next to a major highway, using standard protocols. Particulate matter (PM) total mass, elemental and chemical/mineral compositions of the fine and coarse fractions of traffic-related PM pollutants were determined using several complementary techniques, including gravimetric analysis, x-ray fluorescence, scanning electron microscopy, energy dispersive spectroscopy, and x-ray diffraction. The PM mass concentrations show that PM₁₀ is within acceptable international standards except during dust storms within the sampled periods. Desert dust, crustal minerals, and sea salts are the major natural sources of PM₁₀ pollution. Examples of these minerals are quartz [SiO₂], calcite [CaCO₃], gypsum [CaSO₄·2H₂O], palygorskite [(Mg,Al)₂Si₄O₁₀ (OH)•₄(H₂O], chlorite-serpentine [(Mg,Fe)₆AlSi₃O₁₀ (OH)₈], halite [NaCl] and nitratine [NaNO₃]. Anthropogenic mineral-based pollutants, such as mascagnite [(NH₄)₂SO₄] and koktaite [(NH₄)₂Ca(SO₄)₂·H₂O], were also observed to contribute to PM₁₀. Trace elements such as Zn, Cu, Fe, Cr and Mn that are markers for traffic sources, Ni and V that are markers for heavy oil combustion, and Pb, which is attributed to industrial emissions, were also identified in PM₁₀. Seasonal variation of the average total mass concentrations and the average mass concentration of elements emitted from natural sources show that the hot season is associated with higher pollution levels compared to the cold season due to increased dust events in the spring and summer. Correlation coefficients between elements have identified elements originating from common sources such as dust storms (e.g., Si, Ca, Al, Fe, Ti, Mn) and sea breeze (Cl and Na), in addition to anthropogenic elements. Enrichment factors calculations have identified elements that mainly have crustal origins, and elements that are partially or highly enriched by humans. Anthropogenic elements were more enriched during the cold season due to reduced human activities in the summer..College of Arts and SciencesAmerican University of Sharja
Structural Behavior of Sustainable ECC Produced By 3D Concrete Printing
No full textA Master of Science thesis in Civil Engineering by Ahmad Hitham Bakir entitled, “Structural Behavior of Sustainable ECC Produced By 3D Concrete Printing”, submitted in August 2021. Thesis advisor is Dr. Adil K. Al-Tamimi. Soft copy is available (Thesis, Completion Certificate, Approval Signatures, and AUS Archives Consent Form).The fourth industrial revolution has crossed the threshold of the construction sector by introducing machinery capable of implementing construction tasks, and this auto-manufacturing process is called 3D Concrete Printing (3DCP). It reducces waste, time, workforce and the ability to design complex projects due to the absence of formwork. The key point for a successful 3D printing process is the right selection of printing materials. Earlier research has shown that the brittleness and weakness of the concrete against tension are the main characteristics affecting the widespread of this technology. The aim of this research is to develop Engineered Cementitious Composites (ECC) mixture suitable for the 3DCP process (3D-ECC). The main features of ECC are the tensile strain-hardening properties and ductile failure behavior. The experimental program addressed the fresh properties of the developed 3D-ECC through flowability percentage, initial setting time, extrudability and buildability. A total of 153 specimens have been used to evaluate the mechanical properties such as compressive strength, flexural strength, tensile strength and strain capacity. 80 trial mixes were performed, and one chosen as optimal mix. The flowability percentage and initial setting time for the developed mix were 50% and 14 minutes respectively. The compressive, flexural and tensile strength was 82.0 MPa, 14.2 MPa and 7.73 MPa respectively. In printed samples the test orientation affects the compressive and flexural strength. The compressive strength in the printed samples showed range of 27.9 MPa up to 36.9 MPa for different testing orientations modes. The flexural strength increased to 14.78 Mpa and 18.65 Mpa depends on loading orientation. The printed dog-bone specimens reduced the tensile strength to 4.06 MPa. The tensile strain capacities were 5.21% and 4.79 for the control and printed samples respectively. Both control and printed specimens maintained the tensile strain-hardening behavior. It was observed that replacing cement type I with type V in the control mixes negatively impacted the mechanical performance. The 2% volume fraction of PE-fiber showed higher improvement on the mechanical properties, compared to 3%, 1.5%, 1%, 0.5% and 0%. Finally, flexural strength was increased by 35.7% in R/ECC compared to RCC specimens.College of EngineeringDepartment of Civil EngineeringMaster of Science in Civil Engineering (MSCE
Ultrasound-triggered Immunotherapy for Cancer Treatment: An Update
No full textAmerican University of SharjahDana Gas Endowed Chair for Chemical EngineeringAl-Jalila FoundationAl Qasimi FoundationTakamul programTechnology Innovation Pioneer (TIP) Healthcare AwardsPatient's Friends Committee-Sharja
Enhanced Water Network Leak Detection Methods
No full textA Master of Science thesis in Engineering Systems Management by Suhail Salem Ibrahim Alablam entitled, “Enhanced Water Network Leak Detection Methods”, submitted in April 2021. Thesis advisor is Dr. Noha Mohamed Hassan Hussein. Soft copy is available (Thesis, Completion Certificate, Approval Signatures, and AUS Archives Consent Form).Water is an essential element and source of life. It is considered a scarce element that goes through several procedures for it be consumable. Once the water is treated and is deemed potable or clean, it is then distributed to the consumers through the water distribution network (WDN) from the generation plant or source. However, efficient water distribution is not always the case, as leakages in the (WDN) is inevitable. Leakages occur due to several reasons such as breakages in the pipelines, bad excavations, poor network maintenance and high water pressure. In addition to reducing the efficiency of supplying water, leakages in the WDN creates economic, social and quality/health problems. As a result, many methods are introduced in the water industry to identify leakages in the WDN such as acoustics detection, vibration utilization, underground imaging, modelling, and pressure-based methods. Although acoustic methods are costly and are one of the main detection methods, they suffer major drawbacks including long durations to detect leaks, inaccuracies in detecting leaks in non-metallic pipelines, and manpower dependencies. This research aims at enhancing the reliability and accuracy of acoustic methods through use of machine learning (ML). Most of the surveyed literature that used ML used experimental data or is not applied in an actual WDN to develop the models. In this research, real data collected from Dubai Electricity and Water Authority’s (DEWA) sound sensors that is used to develop and train a ML model. This model predicts the availability of a leak where the sensors are installed at an accuracy of 89% as per the tests conducted on a collection of data from several communities in Dubai. Finally, the economical applicability of using the ML model using the current system and a proposed smart system is conducted.College of EngineeringMultidisciplinary ProgramsMaster of Science in Engineering Systems Management (MSESM
Simultaneous Adsorption and Reduction of Cr(VI) to Cr(III) in Aqueous Solution Using Nitrogen-Rich Aminal Linked Porous Organic Polymers
No full textTwo novel nitrogen-rich aminal linked porous organic polymers, NRAPOP-O and NRAPOP-S, have been prepared using a single step-one pot Schiff-base condensation reaction of 9,10-bis-(4,6-diamino-S-triazin-2-yl)benzene and 2-furaldehyde or 2-thiophenecarboxaldehyde, respectively. The two polymers show excellent thermal and physiochemical stabilities and possess high porosity with Brunauer–Emmett–Teller (BET) surface areas of 692 and 803 m2 g−1 for NRAPOP-O and NRAPOP-S, respectively. Because of such porosity, attractive chemical and physical properties, and the availability of redox-active sites and physical environment, the NRAPOPs were able to effectively remove Cr(VI) from solution, reduce it to Cr(III), and simultaneously release it into the solution. The efficiency of the adsorption process was assessed under various influencing factors such as pH, contact time, polymer dosage, and initial concentration of Cr(VI). At the optimum conditions, 100% removal of Cr(VI) was achieved, with simultaneous reduction and release of Cr(III) by NRAPOP-O with 80% efficiency. Moreover, the polymers can be easily regenerated by the addition of reducing agents such as hydrazine without significant loss in the detoxication of Cr(VI).American University of Sharja
FE modeling of concrete beams and columns reinforced with FRP composites
No full textCompression and flexure members such as columns and beams are critical in a structure as its failure could lead to the collapse of the structure. In the present work, numerical analysis of square and circle short columns, and reinforced concrete (RC) beams reinforced with fiber reinforced polymer composites are carried out. This work is divided into two parts. In the first part, numerical study of axial behavior of square and circular concrete columns reinforced with Glass Fiber Reinforced Polymer (GFRP) and Basalt Fiber Reinforced Polymer (BFRP)bars and spiral, and Carbon Fiber Reinforced Polymer (CFRP) wraps is conducted. The results of the first part showed that the axial capacity of the circular RC columns reinforced with GFRP increases with the increase of the longitudinal reinforcement ratio. In addition, the results of the numerical analysis showed good correlation with the experimental ones. An interaction diagram for BFRP RC columns is also developed with considering various eccentricities. The results of numerical modeling of RC columns strengthened with CFRP wraps revealed that the number and the spacing between the CFRP wraps provide different levels of ductility enhancement to the column. For the cases considered in this study, column with two middle closely spaced CFRP wraps demonstrated the best performance. In the second part of this research, flexural behavior of RC beams reinforced with BFRP, GFRP and CFRP bars is investigated along with validation of the numerical model with the experimental tests. The results resembled the experimental observations that indicate significant effect of the FRP bar diameter and type ont he flexural capacity of the RC beams. It was also shown that Increasing the number of bars while keeping the same reinforcement ratio enhanced the stiffness of the RC beam