Modeling and Simulation of Solar Photovoltaic Cell for the Generation of Electricity in UAE

This paper proposes the implementation of a circuit based simulation for a Solar Photovoltaic (PV) cell in order to get the maximum power output. The model is established based on the mathematical model of the PV module. As the PV cell is used to determine the physical and electrical behavior of the cell corresponding to environmental factors such as temperature and solar irradiance, this paper evaluates thirty years solar irradiation data in United Arab Emirates (UAE), also analyzes the performance parameters of PV cell for several locations. Based on the Shockley diode equation, a solar PV module is presented. However, to analyze the performance parameters, Solarex MSX 120, a typical 120W module is selected. The mathematical model for the chosen module is executed in Matlab. The consequence of this paper reflects the effects of variation of solar irradiation on PV cell within UAE. Conclusively, this paper determines the convenient places for implementing the large scale solar PV modules within UAE.Comment: To be published in 5th International Conference on Advances in Electrical Engineering (ICAEE-2019

Effect of ethylene released from Ethrel in alkaline medium on banana (Musa spp.) fruit ripening

The effect of ethylene gas, released from Ethrel in alkaline medium, on banana fruit ripening was evaluated. ‘Dwarf Cavendish‘ banana fruits were obtained from a private orchard in Sinja, 400 kilometers south of Khartoum. The fruits were harvested at the ’full three quarters‘ maturity stage and transported to the laboratory at the Department of Horticulture, Faculty of Agriculture, University of Khartoum. They were washed with water to remove latex and dust, treated with 10% sodium hypochlorite as a disinfectant and air-dried. The fruits were treated with ethylene gas released from Ethrel at 0 (control), 250, 500 and 1000 ppm for 24 hrs. in hermetically sealed 20 l plastic chambers. Calculated amount of Ethrel that release the desired ethylene gas concentration was added to a beaker containing 15 ml of 40% Na OH in each chamber and immediately closed. After 24 hrs., the chambers were opened and fruits were placed in carton boxes lined with perforated polyethylene films and kept at 18±1˚C and 80%-85% relative humidity. Treatments with ethylene gas released from Ethrel at 250, 500, and 1000 ppm significantly accelerated fruit ripening, the higher the concentration the more was the effect. Depending on concentration, ripening was 2-5 days earlier in the treated fruits, compared with the control. The untreated fruits reached the climacteric peak of respiration after 10 days. Ethylene treatment at 250, 500, and 1000 ppm significantly accelerated the onset of the climacteric peak by 2, 4 and 5 days, respectively, compared with the untreated fruits. The effect of ethylene released from Ethrel on banana fruit ripening was also indicated by increased peel color development, total soluble solids (TSS), total and reducing sugars accumulation and enhanced fruit softening and weight loss.   قُــوم تأثيـر غــاز الٳثليـن المنبعث من الٳثريــل فى وســط قلــوى على ٳنضاج  ثمــار المــوز. وفــرت ثمــار المــوز من صنف ‘دوارف كافندش’ من مزرعـة خاصة  فى منطقة سنجة، 400 كيلومتراً جنوب الخرطوم. حصدت الثمار فى مرحلة ‘ثلاثة أرباع ممتلئة’ من ٳكتمال النمو وتم ترحيلها ٳلى المعمل فى قسم البساتين، بكلية الزراعة، جامعة الخرطوم. غسلت الثمار بالماء لٳزالة العصارة والأتربة وعوملت بهيبوكلوريت الصوديوم (10%) كمطهر ثم  جففت الثمار بازالة الماء العالق بها بواسطة تيار من الهواء. عوملت الثمار بغاز الٳثيلين المنبعث من الٳثريل بتركيز صفر (شاهد) و 250 و500 و1000 جزء فى المليون لمدة 24 ساعة فى حاويات بلاستيكية محكمة الٳغلاق سعة 20 لتراً. أضيفت الكميات المحسوبة من الٳثريل التى تفرز التركيزات المطلوبة الى 15 ملى ليتر من هيدروكسيد الصوديوم (40%) وضعت فى كؤوس زجاجية داخل الحاويات واغلقت الحاويات مباشرة بعد ذلك. بعد 24 ساعة من المعاملة  فتحت الحاويات ووضعت الثمار فى صناديق من الكرتون مبطنة بشرائح البولى ٳثيلين المثقب وحفظت على درجة حرارة 18±1 ˚م ورطوبة نسبية 80% - 85%. أدت المعاملة بالٳثيلين المنبعث من الٳثريل معنوياً ٳلى الٳسراع  بنضج ثمار الموز، وكان التركيز الأعلى أكثر فعالية. كان الٳنضاج أسرع فى الثمار المعاملة بمقدار 5-2 أيام حسب التركيز، مقارنة بالثمار غير المعاملة. أدت المعاملة بغاز الٳثيلين المنبعث من الإثريل معنوياً لتسريع وصول الثمار إلى ذروة التنفس. فقد وصلت الثمار غير المعاملة ٳلى ذروة التنفس، بعد 10 أيــام، وقد تسارع معنوياً وصول الثمار المعاملة بغاز الٳثيلين المنبعث من الٳثريل بتركيز 250 و500 و1000 جزء فى المليون ٳلى ذروة التنفس 2 و4 و5 أيــام، على التوالى، مقارنة بالثمار غير المعاملة. كما انعكس تأثير المعاملة بغاز الٳثيلين، المنبعث من الٳثريل، فى ٳنضاج ثمار الموز فى الزيادة فى تلوين القشرة الخارجية للثمار وتراكم المواد الصلبة الكلية الذائبة والسكريات الكلية  والمختزلة والٳسراع  بليونة لب الثمار وفقدان الوزن فيها.   &nbsp

Thermo-mechanical and wetting behavior of modified SnAg3.5eutectic solder alloy

Effects of adding bismuth content on structure, thermo-mechanical and wetting behavior of SnAg3.5 eutectic alloy have been investigated. Matrix structure of SnAg3.5 eutectic alloy, such as crystallinity, crystal size and lattice parameters, changed after adding bismuth content which effect on all measured properties. Melting temperature of SnAg3.5 eutectic alloy decreased after adding bismuth content. Elastic modulus and contact angle of SnAg3.5 eutectic alloy varied after adding bismuth content. The Sn66.5Ag3.5Bi30alloy has the best solder properties for electronic applications such as lower melting temperature, contact angle and elastic modulus

Effect of quaternary addition on structure, electrical, mechanical and thermal properties of bismuth-tin-zinc rapidly solidified fusible alloy

Effect of quaternary addition, silver or indium, on structure, electrical, mechanical and thermal properties of bismuth-tin-zinc rapidly solidified fusible alloy have been investigated.  Adding silver or indium caused change in alloy matrix microstructure such as matrix parameters and crystal structure of formed phase.  A significant increase in bismuth-tin-zinc alloy strengthens with a little decreased in melting point after adding silver content.  But a significant decrease in bismuth-tin-zinc alloy melting point with a very little increase in alloy strengthens after adding indium conten

The Integration of Neuromorphic Computing in Autonomous Robotic Systems

Deep Neural Networks (DNNs) have come a long way in many cognitive tasks by training on large, labeled datasets. However, this method has problems in places with limited data and energy, like when planetary robots are used or when edge computing is used [1]. In contrast to this data-heavy approach, animals demonstrate an innate ability to learn by communicating with their environment and forming associative memories among events and entities, a process known as associative learning [2-4]. For instance, rats in a T-maze learn to associate different stimuli with outcomes through exploration without needing labeled data [5]. This learning paradigm is crucial to overcoming the challenges of deep learning in environments where data and energy are limited. Taking inspiration from this natural learning process, recent advancements [6, 7] have been made in implementing associative learning in artificial systems. This work introduces a pioneering approach by integrating associative learning utilizing an Unmanned Ground Vehicle (UGV) in conjunction with neuromorphic hardware, specifically the XyloA2TestBoard from SynSense, to facilitate online learning scenarios. The system simulates standard associative learning, like the spatial and memory learning observed in rats in a T-maze environment, without any pretraining or labeled datasets. The UGV, akin to the rats in a T-maze, autonomously learns the cause-and-effect relationships between different stimuli, such as visual cues and vibration or audio and visual cues, and demonstrates learned responses through movement. The neuromorphic robot in this system, equipped with SynSense’s neuromorphic chip, processes audio signals with a specialized Spiking Neural Network (SNN) and neural assembly, employing the Hebbian learning rule to adjust synaptic weights throughout the learning period. The XyloA2TestBoard uses little power (17.96 µW on average for logic Analog Front End (AFE) and 213.94 µW for IO circuitry), which shows that neuromorphic chips could work well in places with limited energy, offering a promising direction for advancing associative learning in artificial systems

The Arab Boycott of Israel

An intelligent understanding of international relationships requires a special study of the critical places where continuous crisis arises. It was felt, therefore, desirable to examine a significant aspect of the conflict between the Arab World and the State of Israel that provides the subject of this study. The economic boycott of Israel has assumed a grave significance in international relations, yet to the author\u27s knowledge this subject has not been investigated in a scholarly and comprehensive manner in any available publication. The writer embarks on this topic in the hope that it may provide the American student of Middle Eastern affairs with the essential data for its clear understanding