沙烏地阿拉伯

The last two decades have seen 60% annual growth rate (AGR) in the global IP traffic and it is expected that the AGR will keep the exponential growth in the next five years. Recent advances in digital signal processing enabled the implementation of the dual polarization (DP) optical coherent digital receivers, which substantially improved their performance. The goal of this research is to develop a prototype of a compact superchannel flexible DP M-ary quadrature amplitude modulation (MQAM) optical transmitter and demonstrate its reconfigurability to accommodate baud rates ranging from 8-32 Gbaud∕s to achieve 1 Tb/s and beyond using the same hardware. The research work consists of three phases; Phase I is the study of transmitter electrical and optical parts; Phase II investigates the potential configurations for frequency comb generator circuit; Phase III deals with the superchannel experimental prototype. The results obtained so far are pertaining to phase I and phase II with some preliminary experimental validation pertaining to phase III. The experimental results show that the measured component characteristics are matched with the components specifications data sheets. Additionally, the designed frequency comb generator was able to create up to 9 optical subcarriers with flat gain of 0.5 dB amplitude. Transmission over optical subcarriers has been attempted using standard optical transmitter. These results show promise towards the generation of a variable data rate up to 1Tb∕s. IEEE and ITU-T standardization effort considered these data rates to appear around 2017, and are intended for Next Generation Regional/Long-haul Networks.

The study aims to evaluate the technique of extracting water from humid air using solar energy through greenhouses in local areas. This technique is believed to provide limited amount of water in areas where potable water is not accessible or abundant. To solve this problem a pyramid-shaped device was designed, it is made of glass panels ad equipped with glass doors, fans operated by solar energy, and multiple shelves covered with fabric to act as Absorbent Calcium Chloride (CaCl2) with a 30% concentration. The doors are open during the night for absorption and closed during the day for energy-generating. Humidity, temperature, and atmospheric pressure are measured every two hours. The amount of water extracted in this area in one full day was around 3.0 liters a day for every square meter. Perhaps the limited amount of water is due to low level of humidity in the area: an average of 50% and temperature of F10 Celsius at night. However, the device itself is independent, does not need power sources, water sources, or infrastructure, can be installed in various places depending on humidity level as well as having the possibility of increasing number or size of device. This makes the device a promising, alternative and environmental friendly solution to produce water. Cost-effective and lighter material can be used to make the device, which will produce an easy-to-use and affordable devices. It is an area in need for further research to improve and further develop it.

Solar energy is a main source of energy that is expected to play a vital role in fulfilling the future global demand of electricity. Design of advanced photovoltaic (PV) system with high electric conversion efficiency is the key for collecting solar energy. A major obstacle hindering useful PV utilization is the deterioration of solar cell efficiency with temperature. The present results of experimentation have shown that there occurs a reduction of approximately 33% in the solar panel efficiency as the operating temperature increases from 45 °C to 68 °C at 1000 W/m2. Therefore, an innovative design of enhanced-performance solar panel using micro flat heat pipe (HP) and thermoelectric generator (TEG) is proposed and experimentally investigated in the presented project. To operate HP and TEG at highest possible efficiency, the condensation section of HP is innovatively cooled by utilize the condensed water inside the evaporator of air conditioner (which is usually between 5-7 °C). Two different types of silicon panel are used in the study: monocrystalline solar panel and polycrystalline solar panel. The results showed that a reduction in average solar panel temperature up to 25% is obtained. In addition, produced power was increased by as much as 50% when solar panel was cooled by the heat pipe. Finally, the feasibility study and cost analysis of the proposed hybrid system are discussed in details and presented.

CNC machines use vector graphics or vector image programs that take time and effort on hobbyists. Therefore, it is important to provide accurate techniques for converting ordinary images available on the Internet or can be designed with easy programs. In order to have precise drill paths read by CNC machines directly and produce a product that does not contain rattles at the edges. This depends on the accuracy of processing the extracted paths. The development of algorithms has been completed Transforms Pixel image into Paths with XYZ extension, which is used to drill material and cut it through CNC machines. And the algorithms are based on transfer images with low quality. And Its Advantage that it can create high Paths with as few points as possible. The program can convert the pixel image into paths, and then converted into g-code, and use it in CNC machines directly.

Water treatment is considered as one of the top research priorities in Saudi Arabia. It has been reported by World Health Organization that, 50,000 people die every day from diseases caused by contaminated water. This research attempts to degrade organic pollutants present in wastewater by using Graphene Oxide synthesized from Saudi natural source. Physical activation of date pits was carried out by carbonizing the samples at different temperatures to produce active carbon. Hammer’s method was employed for the purpose of Graphene Oxide production. The resulted Graphene Oxide has been characterized using FT-Raman, XRD and SEM techniques. Methylene Blue (MB) dye was used as a model organic pollutants to examine the ability of Graphene with the aid of a microwave-system to remove such pollutants. A modified domestic MS furnace with a variable power was used to supply microwave energy. The MB solution 2.5x10-6M was mixed with 0.1gm of Graphene Oxide. The applied microwave power was ranged between 100 to 700 W and the time was set between 0 to 12 minutes. The samples were centrifuged and then filtered through a millipore filter to remove the Graphene Oxide dispersed particles. It is found that, 98% of the initial concentration of MB is removed effectively within 12 minutes under microwave power of 500 W. Chemical oxygen demand is shifted from 450 to 87 mg/L while biological oxygen demand was decreased from 270 to 12.8 mg/L which indicating the degradation of organic constituents. This method can be used for water purification from organic pollutants.

Visual impairment is a major global health problem. In 2017, WHO estimated that there were 253 million people worldwide with this ailment. According to the journal of the American Medical association, the prevalence of visual impairment in the Saudi population is 9.3%. Learning Braille by families of students with visual impairments remains a major obstacle, which precipitates several communication issues. Moreover, difficulties for the students themselves lie in learning braille with languages that include diacritical marks; consequently, affecting their academic progress. My main objective of this project is to help improving life quality of these individuals, and the focus is to advance their social productivity and adaptation. This was accomplished through creating a new simpler Arabic writing system using geometrical shapes. As a part of this project, fifteen participants with visual impairments were interviewed and tried this new writing system; two of them are adults between 25 and 40 years old while the rest are students from 9 to 17 years old. Additionally, 100 participants with visual impairments completed a survey. The data showed that students learned this system in two hours in comparison with students that mastered braille in a few months. This shows that this system is easier to learn and subsequently saves time and effort. The most important value added to this project is that diacritical marks were combined with the alphabet, thereby considerably reducing book sizes compared to Braille-written books. This project presents a novel system that helps people with visual impairments to increase their confidence and independence.