INFLUENCE OF CHEMICAL POLYMER ADDITIVE ON THE PHYSICAL AND MECHANICAL PROPERTIES OF EXPANDED POLYSTYRENE CONCRETE

This research investigated the effect of Renolith chemical polymer additive (RCPA) on the properties of expanded polystyrene (ESP) concrete. Renolith chemical additive is a polymer-based product in a liquid form made up of latex and cellulose. Polystyrene panels were collected as a waste materials and grinded into smaller beads. An experimental investigation was carried out on the EPS replacement ranging from 0% to 100% on the M30 (C25/C30) mix design. Engineering properties, such as workability, density, water absorption, compressive strength, split tensile strength, and flexural strength tests, were studied for both the conventional and EPS concrete. The results indicate that workability increases with increasing amount of EPS contents. Water absorption, compressive, tensile, and flexural strength yielded a satisfactory result at 0-50% replacement. The density of the EPS concrete at 0-37.5% replacement revealed similar values to a conventional concrete; and light-weight concrete (1817.5 - 1030 kg⁄m3) was achieved at a 50-100% replacement. Generally, the addition of the RCPA to the concrete mix has caused an improvement in the properties of the EPS concrete. It was concluded that EPS beads can be used as a partial replacement for coarse aggregates in the production of both structural light-weight and dense concrete. The replacement of coarse aggregate with EPS beads showed a positive application as an alternative material for the construction industry

Validation of the actuator line method for simulating flow through a horizontal axis tidal stream turbine by comparison with measurements

The purpose of the present work is to evaluate the capability of the Actuator Line Method (ALM) to simulate flow through a horizontal axis tidal stream turbine. A numerical model combining the ALM with large eddy simulation technique is developed and applied to compute the flow past a laboratory-scale tidal stream turbine. The flow field is analysed in terms of streamwise mean velocity, turbulence intensity, turbulent kinetic energy and the decay rate of the maximum turbulent kinetic energy behind the turbine. It is found that the ALM performs well in predicting the mean flow and turbulence characteristics behind the turbine. The flow field predicted show a clear transition from an organised vorticity region near the turbine to a highly turbulent flow downstream. The location of this transition and the controlling parameters are discussed but further investigation, both numerical and experimental is required in order to clarify its effects on the flow structure and the performance of downstream turbines in tidal turbine arrays.Supergen Marine Challenge Programme of the EPSRC (EP/J010359/1

A Low-Cost Camera-based Transducer Tracking System for Freehand Three-Dimensional Ultrasound Imaging

Freehand three-dimensional ultrasound (3D US) imaging is commonly used for clinical diagnosis and therapy monitoring. In this technique, accurate tracking of the US transducer is a crucial requirement to develop high-quality 3D US volumes. However, current methods for transducer tracking are generally expensive and inconvenient. This thesis presents a low-cost camera-based system for tracking the US transducer with six degrees of freedom (DoF). In this system, two orthogonal cameras with non-overlapped views are mounted on the US transducer. During US scanning, the two cameras are employed to track artificial features attached to the skin of the patient. A 3D surface map is constructed based on the tracked features and the 3D poses of each camera with respect to the skin are extracted separately. The estimated poses of the two cameras are spatially combined to provide accurate and robust pose estimation of the US transducer. In particular, the fusion of the estimated poses by the two cameras is performed using Kalman filtering based technique, which is a popular optimization technique in motion guidance and tracking. The camera-based tracking of the US transducer has been applied to synthesize freehand 3D US volumes. The performance of the proposed system is evaluated by performing in-vitro 3D US imaging experiments and quantifying the synthesized US volumes. The results demonstrate that two points in the 3D US volume separated by a distance of 10 mm can be reconstructed with an average error of 0.35 mm and a 3D volume of a cylinder can be estimated within an error of 3.8%

Anomalous Separation of Small Y-Chromosomal DNA Fragments on Microchip Electrophoresis

We investigated an anomalous DNA separation where two DNA fragments from the human Y-chromosome sY638 (64 bp) and sY592 (65 bp), with only one base pair difference, were separated. This result is abnormal since in a previous study, we found that 5 bp was the minimum difference between two DNA fragments that the microchip electrophoresis system can separate. The formation of a mini-loop in the structure of the DNA fragment of sY638 (64 bp) was strongly expected to be the reason. To investigate this, we synthesized three modified DNA fragments for sY638 (64 bp), and the modifications were in two expected locations for possible mini-loop formation. Later, the separation between sY592 (65 bp) and the three modified fragments of sY638 (64 bp) was not possible. Thus, we conclude that the formation of a mini-loop in the structure of the DNA is the reason behind this anomalous separation

Meymene (Faryab/Afganistan) bölgesinin etnobotanigi ve tarımsal biyoçeşitliliği

06.03.2018 tarihli ve 30352 sayılı Resmi Gazetede yayımlanan “Yükseköğretim Kanunu İle Bazı Kanun Ve Kanun Hükmünde Kararnamelerde Değişiklik Yapılması Hakkında Kanun” ile 18.06.2018 tarihli “Lisansüstü Tezlerin Elektronik Ortamda Toplanması, Düzenlenmesi ve Erişime Açılmasına İlişkin Yönerge” gereğince tam metin erişime açılmıştır.Bu araştırmada, Afganistan'ın Faryab vilayetinin Meymene bölgesinde etnobotanik araştırmalar yürütülmüş ve bölge halkı tarafından kültüre alınan bitkiler araştırılmıştır. Bu çalışma ile birlikte ayrıca, Afganistan ve Faryab'ın coğrafi, ekonomik ve tarımsal özellikleri üzerinde durup, ekonomik olarak kültürü yapılan bitkiler de incelenmiştir. Çalışma dört bölümden oluşmaktadır. Çalışmanın birinci ve ikinci bölümlerinde giriş ve kaynak araştırması yapılmış, Afganistan ve komşu ülkeler üzerinde yapılmış etnobotanik çalışmalar incelenmiştir. Çalışmanın üçüncü bölümünde Materyal ve Metot açıklanmıştır. Bu bölümde etnobotanik çalışmaların yapıldığı bölge hakkında bilgiler verilmiş, pazar araştırmaları, arazi çalışmaları ve bitki toplama yöntemleri açıklanmıştır. Çalışmanın dördüncü bölümünde Bulgular yer almaktadır. Bu bölümde tespit edilen taksonlar, familya isimlerine göre alfabetik olarak sıralanmış ve taksonların etnobotanik kullanımlarına yer verilmiştir. Çalışmanın son kısmında ise sonuç ve değerlendirmeler yapılmış ve çalışmada kullanılan ekler sunulmuştur.In this research, Ethnobotanical surveys were carried out in the Meymana region of Faryab province of Afghanistan and the cultivated plants were investigated by the people of the region. In addition to this study, we also examined the geographical, economic and agricultural characteristics of Afghanistan and Faryab, and cultivated plants. The study consists of four parts. In the first and second sections of the study, input and source researches were made and the sources on which the researches on ethnobotany were investigated. In the third part of the work, the Material and Method are explained. In this section, information about the area where the ethnobotany studies are made, market researches, field studies and plant collection methods are explained. Findings are in the fourth part of the work. The taxa identified in this section are listed in alphabetical order according to the family names and ethnobotanical uses of the taxa have been included. In the last part of the study, results and evaluations were made and the annexes used in the study were presented

Effect of electrodeposition current density and quarry dust content on the characteristics and tribological properties of ni-recycled quarry dust composite coatings

The study experimentally investigated the effect of various current density and quarry dust content on the surface properties and tribological properties of electrodeposited nickel quarry dust composite coatings on High Speed Steel (HSS) substrate. HSS is widely used as a high speed cutting tool due to their excellent red hardness and good wear resistance. Quarry dust is used in this study as a reinforcement because of its high silica and alumina content, which helps to improve the coating's properties. In order to get finer size of quarry dust particles, quarry dust has undergo ball milling process before electrodeposition process. Various current density with range from 2 A/dm2 to 8 A/dm2 and various quarry dust content with range between 15 g/L to 60 g/L were used in this study as the different range of current density and quarry dust content have different outcome. The composite coatings was characterized using Scanning Electron Microscope (SEM) and X- Ray Diffraction (XRD). The influence of current density and quarry dust content was investigated using hardness test and wear test. As the current density and quarry dust content increases, the hardness of the substrate will increases too. The highest hardness value is obtained when current density is at 6 A/dm2 and quarry dust content is 45 g//L. It is same as for the result of wear test as the wear track length is smaller and the wear occur on the surface. With an increase in current density and quarry dust content, the COF value decreased. Therefore, the optimum experiment's parameters are current density at 6 A/dm2 and a quarry dust content at 45g/L

Improving micro-hardness of stainless steel through powder-mixed electrical discharge machining

Powder-mixed electrical discharge machining (PMEDM) is the technique of using dielectric fluid mixed with various types of powders to improve the machined surface output. The process is fast gaining prominence in electrical discharge machining (EDM) industry. The objective of this investigation is to determine the ability of tantalum carbide (TaC) powder-mixed dielectric fluid to enhance the surface properties of stainless steel material during EDM. The properties of investigated are the micro-hardness and corrosion characteristics of the EDMed surface. Machining was conducted with 25.0g/L concentration of TaC powder in kerosene dielectric fluid. The machining variables used were the peak current, pulse on time and pulse off time. The effects of variables on the micro-hardness of the EDMed surface were determined. Corrosion tests were also conducted on the samples that exhibited higher hardness. Results showed that the EDMed surface was alloyed with elements from the TaC powder. The micro-hardness obtained with PMEDM is about 1,200Hv. This is about 1.5 times obtained without TaC powder in the dielectric fluid. The loss in weight during corrosion test was found to be 0.056 ug/min for PMEDM which was lower than the lowest value of 10.56 ug/min obtained for the EDM without powder dielectric fluid

Numerical simulations of wake characteristics of a horizontal axis tidal stream turbine using actuator line model.

The wake of a laboratory scale tidal stream turbine in a shallow water channel with a turbulent inflow is simulated using the hybrid LES/ALM technique, which combines large eddy simulation with the actuator line method. The turbulent inlet conditions are generated using the mapping method to avoid a precursor running and large space for saving data. The numerical results demonstrated the usefulness of the mapping technique as well as some shortcomings that still remain to be addressed. Good agreement between numerical predictions and experimental data is achieved for both the mean and turbulent characteristics of the flow behind the turbine. The examination of changes in turbulence intensity and turbulent kinetic energy in the streamwise direction confirms the existence of a peak and transition to a highly turbulent flow about three diameters downstream of the turbine, which means that the distinct characteristics of the streamwise changes of turbulence intensity or turbulent kinetic energy may serve as an effective indicator for the flow regime transition and wake behaviour.Supergen Marine Challenge Programme of the EPSRC (EP/J010359/1

Sheehan syndrome: Cardiovascular and metabolic comorbidities

Sheehan syndrome (SS) caused by postpartum hemorrhage leads to partial or complete pituitary hormone deficiency. In addition to lipid and glucose abnormalities, patients with SS have increased body fat, insulin resistance (IR), coagulation abnormalities, increased leptin concentration, low-grade inflammation, and endothelial dysfunction that predispose them to cardiovascular diseases. Untreated growth hormone (GH) deficiency, hypogonadism, and excess glucocorticoid use are considered risk factors for these abnormalities. Compared to other hypopituitary subjects, patients with SS are younger and have a longer duration of disease and severe GH deficiency. Replacement with GH in addition to standard hormone replacement improves their cardiometabolic profile

Design of Miniaturized Multiband Patch Antenna Using CSRR for WLAN/WiMAX Applications

A novel miniaturized multiband, single-feed microstrip patch antenna is presented in this paper for WLAN and WiMAX applications. Both size reduction and multiband are obtained by etching the Multiple Complementary Split Ring Resonators (MC-SRR) on the ground plane of the normal patch antenna. At first, the normal patch antenna produces a single band of 5.15 GHz; 200 MHz (5.0500~5.2499). Subsequently, a Single Circular Split Ring Resonator (SC-SRR) is etched on the ground plane and produces a triple band of: 3.25 GHz; 288 MHz (3.1085~3.3964), 4.5 GHz; 101.3 MHz (4.4488~4.5501), and 5.22 GHz; 220 MHz (5.1191~5.3400) and Double Single Circular Split Ring Resonator (DC-MCSRR) with: 2.99 GHz; 60.7 MHz (2.9574~3.0181), 3.57 GHz; 324.7 MHz (3.4065~3.7312), and 5.1413 GHz; 115.4 MHz (5.0817~5.1971). The working bandwidths cover the desired frequency bands of WLAN 5.2 GHz and WiMAX 3.3/3.5 GHz. The proposed (MC-SRR) antenna can be employed to wireless communication systems due to its simplicity in design, compactness and miniaturization