Radio Frequency Energy Harvesting For Charging Electrical Equipment

Energy is nowadays the main concern for the whole world. Finding renewable sources of energy is a challenging process that attracts the interest of scientists and researchers everywhere. The rapid expansion in electrical technology at this time transformed industry and society. Electricity's extraordinary versatility as a main source of energy means it can be put to an almost unlimited set of applications. The backbone of modern industrial society is, and for the foreseeable future can be expected to remain, the use of electrical power. Electrical energy plays one of the most important rules in human’s daily life in different fields such as transport, heating, lighting, communications, and computation. Moreover, "wireless" as a technology has become a generic and all-encompassing word, which is used to describe communications, in which electromagnetic waves or RF (rather than some form of wire) carry a signal over part or the entire communication path. Most of the mobile devices nowadays like mobile phones and laptops for example are still dependent on centralized power sources to charge their batteries. Energy Harvesting implies that the device can extract its energy from the surrounding environment without the need for these kinds of sources. The objective of this project is to find a way to harvest the Radio Frequency energy from the air and convert it to electrical energy that can be used in charging. This project helps in providing sources of energy to power electrical equipment through using existing sources in the environment. This project will go through different stages to implement the required objective. Researches will be done on the characteristics of RF signals and its harvesting methods

Behaviour of Fiber Reinforced Concrete Beams with Spliced Tension Steel Reinforcement

The aim of the current work is to describe the flexural and bond behaviour of simply supported concrete beams with tension reinforcement spliced at mid-span. The parameters included in the study were the type of the concrete, the splice length and the configuration of the hooked splice. Fifteen beams were cast using an ordinary concrete mix and two fiber reinforced concrete mixes incorporating steel and polypropylene fibers. Each concrete mix was used to cast five beams with continuous, spliced and hooked spliced tension steel bars. A test beam was reinforced on the tension side with two 12-mm bars with a splice length of 20 and 40 times the bar diameter. The hooked bars were spliced along 20 times the bar diameter and provided with 45-degree and 90-degree hooks. The test results in terms of cracking and ultimate loads, cracking patterns, ductility, and failure modes are reported. The results demonstrated the consequences due to short splices and the improvement in the structural behaviour due to the use of hooks and the confinement provided by the steel and polypropylene fibers

Shear Strength of Self-compacting Concrete Containing Different Fillers and Coarse Aggregates

An experimental investigation was conducted to evaluate the shear strength provided by different self-compacting concrete mixes proportioned using different fillers and coarse aggregates. A total of 28 simple beams without web reinforcement were tested in flexure. The test parameters included the use of gravel versus crushed dolomite as coarse aggregates, the amount of longitudinal reinforcement and the composition and percentage of fillers. Dolomite stone powder with either silica fume or fly ash were used as fillers replacing cement aiming at reducing the cost of the mix and obtaining better performance. The test results indicated that the overall structural performance in terms of cracking pattern and shear strength was comparable in all mixes. The potentials of developing shear strength and post cracking shear resistance were better when gravel was used as coarse aggregate and when relatively high fractions of dolomite powder were used as cement replacement

Development of computer software for simulation of transmission line dynamic behavior

Structural failure of transmission line systems is often attributed to dynamic effects such as a broken conductor, a broken insulator, or conductor galloping. The focus of this research was to develop a computer program, DYNTRN, that can analyze the structural response of a transmission line system due to dynamic effects, and present the response in a graphical form. The program uses the stiffness method to analyze a system consisting of conductors, insulators, and support structures. Four types of elements can be used to model the transmission line components: beam elements, cable elements, truss elements, and spring elements. A dynamic condensation method was introduced to efficiently model cable elements. Geometric nonlinearities were accounted for using the Newton-Raphson method. State-of-the-art software tools and object oriented design were used to develop a program that is modular and interactive. An object oriented method was developed to efficiently store and solve the stiffness matrix of the structure. Results obtained from the program were verified using commercial finite element software. The program was also validated using published experimental work. The final product of this research is a computer program that can graphically simulate dynamic behavior of transmission lines

The Content of Some Metal Pollutants in Efeluents of Leather Tanning Industry

This research work was conducted to determine the metal pollutants namely chromium, iron, manganese and zinc that result from the process of leather tanning industry in Khartoum. The determinations were performed in samples collected from wastewaters and tap water of Khartoum Tannery and from two locations at Soba Treatment Plant; (Soba In the inlet and Soba Out the outlet). The results were compared to the permissible levels stated by FAO and Sudanese Standard and Metrology Organization (S.S.M.O).Analysis of Tannery wastewaters showed that: the mean concentrations of chromium, iron, manganese are higher than S.S.M.O and FAO permissible level. The mean concentrations of zinc are below the permitted level stated by S.S.M.O but slightly higher than that of FAO.Analysis of Soba In wastewaters showed that the mean concentrations of chromium, iron and manganese were higher than S.S.M.O and FAO permissible level. Analysis of Soba Out wastewaters showed that: mean concentrations of iron, and chromium are higher than S.S.M.O. and manganese mean concentration is higher than S.S.M.O and FAO permissible level.Reduction of tannery waste pollution impacts can be achieved by applying different treatment techniques to protect the environment and human health

Dynamics and Control of Satellite Relative Motion in Proximity Operations

In this dissertation, the development of relative navigation, guidance, and control algorithms of an autonomous space rendezvous and docking system are presented. These algorithms are based on innovative formulations of the relative motion equations that are completely explicit in time. The navigation system uses an extended Kalman filter based on these formulations to estimate the relative position and velocity of the chaser vehicle with respect to the target vehicle and the chaser attitude and gyro biases. This filter uses the range and angle measurements of the target relative to the chaser from a simulated LIDAR system, along with the star tracker and gyro measurements of the chaser. The corresponding measurement models, process noise matrix, and other filter parameters are provided. The guidance and control algorithms are based on the glideslope used in the past for rendezvous and proximity operations of the Space Shuttle with other vehicles. These algorithms are used to approach, flyaround, and to depart from a target vehicle in elliptic orbits. The algorithms are general and able to translate the chaser vehicle in any direction, decelerate while approaching the target vehicle, and accelerate when moving away. Numerical nonlinear simulations that illustrate the relative navigation, attitude estimation, guidance, and control algorithm\u27s, as well as performance and accuracy are evaluated in the research study

Resistance of Melons (Cucumis melo L.) to leafminers (Liriomyza spp.; Diptera: Agromyzidae

The vegetable leafminers, Liriomyza spp. (Diptera: Agromyzidae( are considered as one of the most important pests affecting vegetable crop production in many parts of the world. The reason why Liriomyza spp. are serious problems is the enormous build up of populations which are able to feed on a wide range of plant species. In the Sudan, two species of Liriomyza were reported: L. trifolii Burgess and L. sativae Blanchard' causing severe damage to a wide range of hosts. Recent surveys in central Sudan confirmed the existence of both species and that Liriomyza sativae was more common than L. trifolii on different host plants (Salah, 2001). The host range of L. sativae is confined to three families: Cucurbitaceae, Leguminaceae and Solanaceae, while L. trifolii is a polyphagous species, which attacks tomato, cucumber, lettuce, pepper and is also a serious problem on melons (Dogimont et al., 1999)

Optimization of driving mode switching strategy for a multimode plug-in hybrid electric vehicle

Hybrid electric vehicles have become increasingly popular recently. Switching from internal combustion engine to battery as a clean source of energy is considered as a solution to reduce city pollution due to vehicle emissions. PHEV is a viable balance between the two sources of energy to achieve higher fuel economy with lower emissions. For a multimode PHEV, the car switches among three operation modes; namely electric mode, series mode, and parallel mode to maximize fuel economy based on the driving conditions. In this work, minimization of fuel consumption is used to optimize the mode switching strategy for a PHEV. The study is conducted using a reference vehicle that resembles 2014 Honda Accord Plug-in Hybrid vehicle. Global optimization with constraints using pattern search method is utilized. Starting from a switching strategy with 〖MPG〗_e = 30, optimization increased fuel economy to 〖MPG〗_e = 51.4 for a combined cycle (FTW75 and HWFET). Optimization proved to be a feasible method to improve mode switching strateg

Role of MRI Diffusion Weighted Imaging in Evaluation of Gynecological Pelvic Masses

Background: Gynecological Pelvic masses are common problem that are commonly discovered during routine gynecologic or physical examinations. Radiologists routinely evaluate a wide range of pelvic masses during daily practice. Proper management depends on proper preoperative assessment with the help of clinical examination, laboratory tests and different imaging modalities. Radiological evaluation includes ultrasonography (US), computed tomography (CT) and recently magnetic resonance imaging (MRI). Diffusion weighted imaging (DWI) is widely used in protocols for magnetic resonance imaging (MRI) of the female pelvis. It provides functional and structural information about biological tissues, without the use of ionizing radiation or intravenous administration of contrast medium. Objective: This study aimed to evaluate the role of diffusion weighted imaging in the characterization of gynecological pelvic masses and differentiation between benign and malignant tumors. Patients and Methods: This study was performed on 63 patients. All patients had US findings of uterine and adnexal lesions then they underwent conventional MRI with contrast & DWI. Results: DWI is significant promising tool factors for characterization of gynecological tumors and differentiation between benign & malignant lesions with high sensitivity 95% (81%:99% with 95% CI). The sensitivity, specificity and accuracy of detection of the nature of the lesions have been increased after adding of DWI to the conventional imaging. Conclusions: Adding of DWI to the conventional MRI improves the sensitivity and specificity of diagnosis and allows confident diagnosis and differentiation between benign and malignant lesions