Radiography, ultrasonography and computed tomography of the dromedary camel tarsus (One humped camel)

The dromedary camel has a very high economic importance in the Arabic countries. Nevertheless, there is a very little background literature on the use of ultrasound (US) and computed tomography (CT) in dromedaries in comparison to other domestic and farm animal species. Therefore, the tarsal region of six cadaver limbs, obtained from three orthopedic disease free dromedary camels, was evaluated via radiography, US and CT. The limbs were frozen and sectioned transversely, sagittaly and dorsally. The anatomic structures were identified and correlated to the analogous structures on the corresponding CT slices and US images and published in two manuscripts. Radiography was performed in both standard (0º and 90º) oblique (45º and 135º) radiographic projections. The tarsus was investigated via US in four planes (dorsal, medial, lateral and plantar) and each plane was scrutinized in four levels (calcaneal tuber, tibial malleoli, base of calcaneus and proximal head of metatarsus) in both transverse and longitudinal views. Radiography provided a good representation of the bony structures and articulations with little information on the soft tissues of the tarsus and superimposition of the tarsal bones. Ultrasonography furnished adequate delineation of the peri-articular tissues of the tarsus and was limited to the bone surface. Computed tomography provided cross sectional imaging of the dromedary tarsus without bone and soft tissue overlap and allowed visualization and differentiation of tissues in almost every situation. This work was undertaken to document the normal appearance of the dromedary camel tarsus via radiography, ultrasonography, and computed tomography which may be used as a resource for interpretation of dromedary tarsal pathology using various diagnostic imaging modalities

A Study Of Cooperative Spectrum Sharing Schemes For Internet Of Things Systems

The Internet of Things (IoT) has gained much attention in recent years with the massive increase in the number of connected devices. Cognitive Machine-to-Machine (CM2M) communications is a hot research topic in which a cognitive dimension allows M2M networks to overcome the challenges of spectrum scarcity, interference, and green requirements. In this paper, we propose a Generalized Cooperative Spectrum Sharing (GCSS) scheme for M2M communication. Cooperation extends the coverage of wireless networks as well as increasing their throughput while reducing the energy consumption of the connected low power devices. We study the outage performance of the proposed GCSS scheme for M2M system and derive exact expressions for the outage probability. We also analyze the effect of varying transmission powers on the performance of the system

Adaptive Relay-Selection In Decode-And-Forward Cooperative Systems

In the past few years adaptive decode-and-forward cooperative diversity systems have been studied intensively in literature. Many schemes and protocols have been proposed to enhance the performance of the cooperative systems while trying to alleviate its drawbacks. One of the recent schemes that had been shown to give high improvements in performance is the best-relay selection scheme. In the best-relay selection scheme only one relaying nodes among the relays available in the system is selected to forward the source\u27s message to the destination. The best relay is selected as the relay node that can achieve the highest end-to-end signal-to-noise ratio (snr) at the destination node. Performance improvements have been reported as compared to regular fixed decode-and-forward relaying in which all relays are required to forward the source\u27s message to the destination in terms of spectral efficiency and diversity order. In this thesis, we use simulations to show the improvement in the outage performance of the best-relay selection scheme

Co-design of Reconfigurable and Multifunction Passive RF/Microwave Components

In order to meet the market demands, multi-band communication systems that are able to accommodate different wireless technologies to be compatible with different wireless standards should be investigated and realized. Multifunction and multi-band RF front-end components are promising solutions for reducing the size and enhancing the performance of multi-band communication systems. This dissertation focuses on the design and implementation of different multifunction and tunable microwave components for use in multi-standard, flexible transceiver. For frequency-domain duplexing (FDD) communication systems, in which the uplink and downlink channels are carried on different RF frequencies, a diplexer is an essential component to separate the transmitting and receiving signals from the antenna. Electrically tunable diplexers simplify the architecture of reconfigurable RF-front end. Moreover, in modern communication systems, the crowding of the spectrum and the scaling of electronics can result in higher common-mode interference and even-order non-linearity issues. In this dissertation, three tunable compact SIW-based dual-mode diplexers, with various SE (single-ended) and BAL (balanced) capabilities, are introduced for the first time. The dual-mode operation results in a dependent tuning between the two ports. The presented designs are for SE-SE, SE-BAL, and BAL-BAL. However, based on the presented design concepts, any combination of the diplexer ports can be achieved in terms of supporting the balanced and single-ended system interface. The fabricated diplexers show low insertion loss, high isolation, good tuning range and high common mode rejection. Tunable bandstop filter (BSF) is one of the essential components in the design of RF front-ends that require wide-band operations. A wide-open front-end leaves the receiver vulnerable to jamming by high-power signals. As a result, this type of front-ends requires dynamic isolation of any interfering signal. Realization of such filters in a balanced configuration, as a second function, is an important step in the realization of full-balanced RF front-ends. Balanced (differential) circuits have many important advantages over unbalanced (single-ended) circuits such as immunity to system noise, reduction of transient noise generation and inherent suppression of even-order nonlinearities. All reported balanced filters are bandpass filters that target wide pass-bands and high common-mode rejection. These filters are necessary for wide-band RF front-ends but, as mentioned above, leave the system open to interferers and jammers. In this dissertation, a new differential coupling structure for evanescent-mode cavity resonators is developed, enabling the design of fully-balanced tunable BSF. The proposed filter is tunable from 1.57-3.18 GHz with 102% tuning range. In addition, over the full range, the measured 10-dB fractional bandwidth ranges from 1-2.4%, and the attenuation level is better than 47 dB. Lastly, Substrate Integrated Waveguide (SIW) evanescent-mode cavity resonators (EVA) are employed in the design of RF couplers, quadrature hybrid and rat-race couplers. These couplers are used in the design of numerous RF front-end components such as power amplifiers, balanced mixers, and antenna array feeding networks. Utilizing such resonators (EVA) in the design allows the couplers to have wide spurious-free range, low power consumption, high power handling capability and both tunability and filtering capabilities. The proposed quadrature hybrid coupler can be tuned starting from 1.32–2.22 GHz with a measured insertion loss range from 1.29 to 0.7 dB. The measured reflection and isolation are better than 12 dB and 17 dB, respectively. Moreover, the coupler has a measured spurious free range of 5.1–3fo (lowest–highest frequency). Regarding rat-race coupler, two designs are introduced. The first design is based on a full-mode cavity while the second one is more compact and based on a half-mode cavity. Both designs show more than 70% tuning range, and the isolation is better than 30 dB

Safety assurance of high voltage control module in a robotic paint system

Master's thesis in Mechatronics (MAS500

Adaptive optics: principles and applications in ophthalmology

This is a comprehensive review of the principles and applications of adaptive optics (AO) in ophthalmology. It has been combined with flood illumination ophthalmoscopy, scanning laser ophthalmoscopy, as well as optical coherence tomography to image photoreceptors, retinal pigment epithelium (RPE), retinal ganglion cells, lamina cribrosa and the retinal vasculature. In this review, we highlight the clinical studies that have utilised AO to understand disease mechanisms. However, there are some limitations to using AO in a clinical setting including the cost of running an AO imaging service, the time needed to scan patients, the lack of normative databases and the very small size of area imaged. However, it is undoubtedly an exceptional research tool that enables visualisation of the retina at a cellular level

A Proposed Artificial Intelligence-Based System for Developing E-management Skills in Saudi Primary Schools

This study aims to investigate the impact of Artificial intelligence-driven solutions on school leaders’ proficiencies. Leaders have the responsibility of making decisions in educational institutions as well as carrying out routine tasks daily. Artificial intelligence-assisted applications have noteworthy contributions to the field of educational management. The scope of this study is limited to selected features; data analytics, chatbot, and e-survey. The basic design of this study started with analyzing literature in this domain. This was followed by designing a system consisting of four models: building a dashboard, predicting students’ results, creating a chatbot for responding to parents’ queries and creating an e-survey for measuring staff satisfaction. The participants of this study consist of 35 school leaders, whereas the sample was one group that was exposed to special treatment. A pre/post-test was conducted to examine the impact of the treatment, in addition to an observation card that was used to measure the treatment’s impact on the technical domains. The researchers used SPSS to analyze the study’s results. The prominent finding of this study is the significant impact of Artificial intelligence on leaders’ competencies; the difference between mean scores in both pre and post-test application and post-application for the observation card has proven the positive impact of the proposed treatment

MODELLING THE DETERMINANTS OF COMMERCIAL VEHICLE OWNERSHIP: AN APPLICATION TO WINDSOR, ONTARIO, CANADA

The majority of the existing transportation literature has been concerned with private travel activities. Fortunately, the importance of commercial vehicles and their movement has led to a surge of research activities to analyze and understand commercial vehicle movements. However, an absent theme in the emerging research activities is the process governing commercial vehicle ownership. This project attempts to fill the gap in the existing literature by developing a new model of commercial vehicle ownership. The focus is on studying the spatial prevalence of the various types of commercial vehicles, as derived from the Gross Vehicle Weight (GVW) classes, in a given traffic analysis zone (TAZ) within an urban area using various types of statistical methods. The results allow us to unravel the significant factors explaining the variability in the spatial distribution of commercial vehicles. The obtained statistical results form the basis for developing predictive urban commercial vehicle ownership location models

Longitudinal genotype-phenotype analysis in 86 PAX6-related aniridia patients

Aniridia is most commonly caused by haploinsufficiency of the PAX6 gene, characterised by variable iris and foveal hypoplasia, nystagmus, cataracts, glaucoma and aniridia related keratopathy (ARK). Genotype-phenotype correlations have previously been described, however detailed longitudinal studies of aniridia are less commonly reported. We identified eighty-six patients from sixty-two unrelated families with molecularly confirmed heterozygous PAX6 variants from a United Kingdom (UK)-based single-centre ocular genetics service. They were categorised into mutation groups and retrospective review of baseline to most recent clinical characteristics (ocular and systemic) were recorded. One hundred and seventy-two eyes were evaluated, with a mean follow up period of 16.3 ± 12.7 years. Nystagmus was recorded in 87.2%, and foveal hypoplasia in 75%. Cataracts were diagnosed in 70.3%, glaucoma in 20.6% and ARK in 68.6% of eyes. Prevalence, age of diagnosis and surgical intervention varied amongst mutation groups. Overall, the missense mutation sub-group had the mildest phenotype, and surgically naïve eyes maintained better visual acuity. Systemic evaluation identified type 2 diabetes in 12.8%, which is twice the UK prevalence. This is the largest longitudinal study of aniridia in the United Kingdom, providing insights into prognostic indicators for patients and guiding clinical management of both ocular and systemic features