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A mobile Based Platform for Monitoring Respiratory Diseases
No full textA Master of Science thesis in Computer Engineering by Fatma Khalil Zubaydi entitled, "A mobile Based Platform for Monitoring Respiratory Diseases" submitted in September 2016. Thesis advisor is Dr. Assim Sagahyroon and thesis co-advisors are Dr. Fadi Aloul and Dr. Hasan Mir. Soft and hard copy available.Chronic respiratory diseases are diseases of the airways and other structures of the lung, usually resulting in difficulty in breathing and other symptoms. Chronic obstructive pulmonary disease (COPD) and Asthma are considered to be the most common of respiratory diseases. By taking into consideration the possibility of disease worsening over time and the negative impact on patient’s daily activities, the continuous monitoring and managing of these diseases has become a necessity. Currently, spirometry remains the recommended test for monitoring and diagnosing both, COPD and Asthma. A patient suffering from COPD or Asthma should be able to monitor his disease in order to avoid a worsening condition over time or exacerbation of the disease in severe cases. Proper monitoring requires regular visits to medical centers for spirometry checks, or else the purchase and use of a portable spirometer; both options are costly in terms of money and time. In this work and due to the pervasiveness and advancement of smartphones, we attempt to make use of their built-in sensors and ever increasing computational capabilities to provide patients with a mobile-based spirometer capable of diagnosing and managing COPD and Asthma in a reliable and cost effective manner. We developed a model that allows the computation of two critical lung parameters: FVC and FEV1 by establishing a relationship between the frequency response of human exhalation recorded by mobile microphone, and the actual flow rate. These two parameters and the FEV1/FVC ratio are critical in assessing the progress and status of the diseases. We designed a Pretest Activity that together with these computed lung parameters is used in the diagnosis phase. Sample data used to test the system is collected from patients at both Oriana, and Al Zahra hospitals in Sharjah, United Arab Emirates (UAE), under the supervision of consultant pulmonologists. Results and the medical diagnosis of the implemented system proved to be in very close proximity with those produced by clinical spirometers. Our work is an attempt among many to confirm the notion that mobile Health (m-Health) can and will play an important role within the healthcare industry in the near future.College of EngineeringDepartment of Computer Science and EngineeringMaster of Science in Computer Engineering (MSCoE
Capacity of Fox's H-function Fading Channel with Adaptive Transmission
No full textNovel closed-form exact expressions for the capacity of the recently-introduced Fox's H-function fading channel are derived. The expressions are obtained assuming different types of adaptive transmission strategies, namely, channel inversion with fixed rate (CIFR), truncated channel inversion with fixed rate (TIFR), optimum rate adaptation with fixed power (ORA) and optimum power and rate adaptation (OPRA). The obtained expressions are versatile and can be used to evaluate the capacity for virtually any fading channel one might be interested in as a special case
Artifacts in knowledge management research: a systematic literature review and future research directions
No full textPurpose - The purpose of this article is to assess the role of artifacts in the knowledge management field in the past 18 years (1997-2015) and to identify directions for future research.
Design/methodology/approach - The authors conducted a systematic literature review of 101 articles published in 7 journals retrieved from EBSCO and Google Scholar online research databases. The framework for analysis included 13 codes, i.e. author(s), title, year of publication, typology, theoretical lens, categorizations, methods for empirical work, relevancy, level of analysis, keywords, findings, research themes, and future research directions. Codes were analyzed using qualitative and quantitative methods.
Findings - Findings lacked cumulativeness and consistency in the current knowledge management debate. Empirical works outnumbered conceptual contributions by two to one, and the majority of articles focused at the organizational level of analysis. Knowledge management systems, knowledge sharing, and digital archives were the major research themes connected to artifacts, together with other closely aligned concepts such as learning and online learning, knowledge transfer and knowledge creation.
Research limitations - This study has temporal and contextual limitations related to covered time span (18 years) and journals subscription restrictions.
Originality/value - This article is a first attempt to systematically review the role of artifacts in knowledge management research and therefore it represents a primary reference in the knowledge management field. It provides directions to future theoretical and empirical studies as well as suggestions to managerial practices
On The Unit Dot Product Graph Of A Commutative Ring.
No full textA Master of Science thesis in Mathematics by Mohammad Ahmad Abdulla entitled, "On The Unit Dot Product Graph Of A Commutative Ring," submitted in January 2016. Thesis advisor is Dr. Ayman Badawi. Soft and hard copy available.In 2015, Ayman Badawi (Badawi, 2015) introduced the dot product graph associated to a commutative ring A. Let A be a commutative ring with nonzero identity, 1 n < 1 be an integer, and R =A x A x ... x A (n times). We recall from (Badawi, 2015) that total dot product graph of R is the (undirected) graph TD(R) with vertices R* = R \ {(0, 0, ..., 0)}, and two distinct vertices x and y are adjacent if and only if xy = 0 [is an element of] A (where xy denote the normal dot product of x and y). Let Z(R) denotes the set of all zero-divisors of R. Then the zero-divisor dot product graph of R is the induced subgraph ZD(R) of TD(R) with vertices Z(R) = Z(R)* \ {(0, 0, ..., 0)}. Let U(R) denotes the set of all units of R. Then the unit dot product graph of R is the induced subgraph UD(R) of TD(R) with vertices U(R). Let n 2 and A = Zn. The main goal of this thesis is to study the structure of UD(R = A x A).College of Arts and SciencesDepartment of Mathematics and StatisticsMaster of Science in Mathematics (MSMTH
Flexural Strengthening of Reinforced Concrete Beams with Externally Side-Bonded CFRP Laminates
No full textA Master of Science thesis in Civil Engineering by Ahmad S. D. Salama entitled, "Flexural Strengthening of Reinforced Concrete Beams with Externally Side-Bonded CFRP Laminates," submitted in April 2016. Thesis advisor is Dr. Rami Hawileh and thesis co-advisor is Dr. Jamal A. Abdalla. Soft and hard copy available.Carbon fiber reinforcement polymer (CFRP) composite sheets and plates are widely used nowadays in civil engineering applications to externally strengthen structural concrete elements against deficiencies in flexure and shear. These deficiencies could be due to an increase in loading, earthquake damage, or even design and/or construction defects. The current state of the art technique used in flexural strengthening of reinforced concrete (RC) beams is the externally bonding of CFRP sheets or plates to the beam's tensile bottom surface (soffit). However, the beam's soffit may be obstructed and not always readily accessible for strengthening. Only the beam's sides that may be exposed become the only accessible area for strengthening using side-bonded CFRP sheets or plates. As a result, this study aims to evaluate the performance of RC beams externally strengthened in flexure with side-bonded CFRP composite sheets. Accordingly, a total of 25 beams has been cast and strengthened in flexure with different configurations of side-bonded CFRP sheets. The strengthening scheme, amount of steel and CFRP reinforcement were varied to examine their effect on the flexural strength and ductility of RC beams. The flexural strength and load-deflection response curves of the tested specimens were also predicted using the ACI 440.2R-08 design guidelines. The predicted results were in good agreement with the experimental results. It was concluded that the side-bonded strengthening scheme is less efficient than that of the conventional soffit-bonded one; however, it is a viable solution when the beam's soffit is not accessible for strengthening. The debonding mechanism of the side-bonded specimens justifies the efficiency reduction in this technique, since the stress distribution is not uniform along the CFRP sheets as in the soffit-bonded ones. However, as the reinforcement ratio increases, the performance of both strengthening schemes exhibit similar performance.College of EngineeringDepartment of Civil EngineeringMaster of Science in Civil Engineering (MSCE
Strengthening of High Strength Reinforced Concrete Slabs with CFRP Laminates
No full textA Master of Science thesis in Civil Engineering by Hasan Saleh Mahmoud entitled, "Strengthening of High Strength Reinforced Concrete Slabs with CFRP Laminates," submitted in May 2016. Thesis advisor is Dr. Rami Hawileh and thesis co-advisor is Dr. Jamal El-Din Abdalla. Soft and hard copy available.During the last few decades, engineers and researchers used high-strength concrete to cast reinforced concrete (RC) structures. Accordingly, the dead weight of buildings and structures were reduced significantly, which allowed engineers to construct higher and larger buildings. Reinforced concrete slabs are the largest structural members in buildings. This research aims to reduce the thickness of RC slabs using high-strength concrete strengthened with carbon reinforced polymers (CFRP) laminates in flexural. In this study the behavior of 100 mm thick RC slabs with different concrete compressive strengths of 40, 70, and 100 MPa was inspected. A total of 54 RC slab specimens were cast and tested under two-point loading until failure. The specimens were divided into three groups having different flexural steel reinforcement ratios of 0.45, 1.00, and 1.79%, respectively. Each group of specimens was strengthened with one and two layers of CFRP sheets, which were externally attached to the soffit of the RC slabs, to enhance their flexural capacity. The test results indicated an increase in the load-carrying capacity of the strengthened slabs in the range between 12 to 378 %. It was also observed that the highest contribution was for those specimens with low reinforcement ratio, in which their control specimens failed by tensile membrane action. The mid-span deflection response curves and load-carrying capacity of the slabs were also predicted with a good level of accuracy using the design guidelines of ACI 440-2R-08. In conclusion, strengthening of high-strength thin RC slabs with CFRP laminates is a valid choice to enhance their flexural behavior, with a minimal increase in their dead load, due to the lightweight of the CFRP laminates.College of EngineeringDepartment of Civil EngineeringMaster of Science in Civil Engineering (MSCE
Preparation of albumin-targeted liposomes and the study of their release characteristics using ultrasound
No full textA Master of Science thesis in Chemical Engineering by Renad Turki entitled, "Preparation of albumin-targeted liposomes and the study of their release characteristics using ultrasound," submitted in January 2016. Thesis advisor is Dr. Ghaleb Al Husseini. Soft and hard copy available.The main objective of this thesis was to investigate the enhancement of drug delivery using targeted liposomes triggered by ultrasound. In this thesis, a thorough literature review on cancer and drug delivery systems (especially liposomes) was conducted. An overview of nanoparticles as drug delivery carriers, different types of drug targeting and the use of ultrasound to control drug release from nanocarriers is also reported. In the study, albumin-targeted liposomes (proteoliposomes) were prepared and loaded with the model drug calcein. The release studies were performed using different ultrasound power densities at 20-kHz. The size of both liposomes types was determined by Dynamic Light Scattering. The release experiments were done online, by continuously measuring the increase in fluorescence when the calcein self-quenching was relieved upon release. The 20-kHz ultrasound was applied in 20 s pulses with a 10 s inter-pulse interval. In the end, total release was determined by lysing the remaining liposomes with Triton X-100. The prepared liposomes were large unilamellar vesicles with diameters 208.52±11.50 nm (non-targeted control liposomes) and 218.27±12.73 nm (albumin liposomes). Although albumin liposomes are larger, the difference was not significant. For both liposome types, the 20-kHz ultrasound-induced release was fast, reaching a stable value after 150 - 250 s. The release rate increased with increasing power densities, and the final percentage of release was higher than 90% for all power densities. For the same power density, the release from non-targeted liposomes was significantly faster than for albumin liposomes, which suggests that the addition of the albumin moiety changes the acoustic properties of the liposomes, apparently increasing their stability and making them less susceptible to ultrasound. The findings allowed us to conclude that these liposomes could be promising nanocarriers for the anti-cancer drug doxorubicin, enhancing the therapeutic efficacy of the drug and decreasing the side effects of the common chemotherapy cancer treatment.College of EngineeringDepartment of Chemical EngineeringMaster of Science in Chemical Engineering (MSChE
Evaluating the Structural Performance and Durability of CNT and Polyethylene Fiber-Reinforced Concrete
No full textA Master of Science thesis in Civil Engineering by Rashad R. Al Araj entitled, "Evaluating the Structural Performance and Durability of CNT and
Polyethylene Fiber-Reinforced Concrete," submitted in November 2016. Thesis advisor is Dr. Adil Al-Tamimi and thesis co-advisor is Dr. Noha Hussein. Soft and hard copy available.Concrete, despite being one of the most produced materials in the world, still has weaknesses and drawbacks. The major concern of cementitious materials in structural applications is their quasi-brittle behavior, which causes them to crack and lose strength and durability. Recent studies have incorporated micro-fibers in concrete mixes to control crack growth at the micro-level. However, new insights will help control cracks at the nano-level by incorporating nano-reinforcement. Carbon nano-tubes (CNTs) are promising nano-engineered materials that could be a perfect fit for this role. However, no major implementation of CNTs has yet been witnessed in this field. Therefore, this research studies the effects of incorporating CNTs, polyethylene (PE) fibers, and their combination on the structural performance and the durability of concrete. In this study, four different concrete mixes were prepared (control, control+ CNTs, control+ PE fibers, and control+ CNTs+ PE fibers), and a total of forty specimens (cubes, cylinders, and prisms) were tested. Structural performance was assessed in terms of compressive and flexural strengths. Durability was assessed in terms of chloride penetration into concrete using rapid chloride permeability test (RCPT). Furthermore, microstructures of concretes were studied with scanning electron microscope (SEM) and energy dispersive X-ray spectroscopy (EDX). The study also included finite-element modeling for the novel concrete (incorporating both CNTs and PE fibers) in ABAQUS, and the model was validated against the experimental results for future applications. While no major impacts on compressive strengths were witnessed, ductility in compression was enhanced by up to 50%. Likewise, results from the 3-point-bending tests showed that the flexural strengths were enhanced by up to 194%. Similarly, up to 398% improvement in flexural strain gain was recorded. As for the durability, RCPT results were opposite to expectations, since mixes incorporating CNTs had more than double the chloride permeability to that of the control mix. However, based on literature, it is concluded that RCPT most probably fails to be an accurate test to measure the chloride permeability of concretes containing CNTs. The fresh properties of concrete were not considerably affected by the addition of CNTs, PE fibers, or their combination. However, mixes incorporating PE fibers had around 50% less workability than the control mix.College of EngineeringDepartment of Civil EngineeringMaster of Science in Civil Engineering (MSCE
Lateral Confinement of RC Columns by Internal Structural Steel Strip Bands
No full textA Master of Science thesis in Civil Engineering by Ahmad Towaiq entitled, "Lateral Confinement of RC Columns by Internal Structural Steel Strip Bands," submitted in December 2016. Thesis advisor is Dr. Sami Tabsh. Soft and hard copy available.The most common type of lateral reinforcement in reinforced concrete (RC) columns is rectilinear steel ties. Ties provide confinement to the concrete core increasing its compressive strength and ductility. Past studies have shown that tied columns fail while the stress in the ties is below the yield strength, which represents inefficient use of the material. Furthermore, ties are labor intensive making them costly and time-consuming to fabricate and install. Additionally, the presence of end hooks to anchor them into the concrete adds up to the material cost. A new method of lateral reinforcement is explored in this study where the concrete column core is confined by Internal Structural Steel Strip Bands (ISSSBs) in lieu of ties. These ISSSBs are cut from structural steel square or rectangular tubes. This method has the potential of improving the structural behavior of RC columns without increasing the amount of lateral steel. There are two main objectives for this study. The first one is to verify the feasibility of the use of ISSSBs as lateral reinforcement in RC columns, while the second is to develop design recommendations for columns transversely reinforced with ISSSBs. To achieve the stated objectives, five variables are considered: (1) aspect ratio of the cross section, (2) spacing of ISSSBs, (3) thickness to width ratio of the ISSSBs, (4) compressive strength of concrete, and (5) area of the column's cross-section. The experimental work involved the construction and testing of 25 short specimens with different configurations under concentric axial compression. On average, the results of the study showed that the use of ISSSBs can cause 5% increase in the strength, 65% increase in initial stiffness, and 20% increase in ductility of the concrete core compared to the use of ties. Moreover, it was found that the lateral confining steel is more effective in moderate and high strength concrete than in low strength concrete. The lateral steel volumetric ratio has little effect on strength but great impact on stiffness and ductility. Findings of the study showed that the strength of ISSSB-confined columns can be predicted by the tied columns equation of the ACI 318M-14.College of EngineeringDepartment of Civil EngineeringMaster of Science in Civil Engineering (MSCE
Total Damages Quantification Method for Float Allocation
No full textA Master of Science thesis in Civil Engineering by Khaled M. S. Jadallah entitled, "Total Damages Quantification Method for Float Allocation," submitted in July 2016. Thesis advisor is Dr. Sameh Monir El-Sayegh. Soft and hard copy available.Construction projects involve several contracting parties such as clients, contractors, consultants and many others. These contracting parties tend to use the float of noncritical activities for their own benefits, such as the incorporation of change orders and for resource management purposes. Float ownership is one of the most debatable issues in the construction industry. In fact, using float by one party might yield in damages caused to the other party, such as increasing the risk towards finishing the project, disturbance of resource histogram and losses in the time value of money. This Thesis proposes a new method that can fairly allocate float ownership between all the project parties by considering all the damages that might occur when float is used. The total damages quantification method for float allocation aims to allocate float ownership for each party prior to signing the contract and specifies their liability towards using the float during the project execution. The float allocation process is performed using the total damages model that determines the optimum project schedule, with the lowest cost, considering the additional costs related to changes from that schedule due to the time value of money, resource leveling, and the increase of risk of delaying the project completion. Thus, contractors can set up their bid price based on the baseline schedule requirements and the liability of using float. Consumption of additional float can be quantified as damages using the total damages quantification model. Hence, float ownership for each party can be defined in the contract baseline schedule. Subsequently, unless all parties are committed to the baseline schedule, damages should be quantified as monetary values and the affected party should be compensated. As a result, by introducing this method, the contracting system clarifies all parties' rights and liabilities towards floats of non-critical activities, which in turn minimizes conflicts and claims that might end up by terminating projects and raising cases in courts of law. A case study is conducted in this research in order to show how each party of the construction project can suffer from damages due to the use of float, and how the Total Damages Method can be
used in order to claim these damages.College of EngineeringDepartment of Civil EngineeringMaster of Science in Civil Engineering (MSCE