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World over the air travel is the fastest growing source of greenhouse gases leading towards global climate change. Estimates show that each long distance flight of a 747 adds approximately 400 tons of CO₂ to the atmosphere. Like elsewhere in Libya too with the expected threefold increase in air travel over the next 30 years, the reliability and environmental impact of aviation are becoming critical issues for the future of flight in the country.

This paper is designed to present greener sky initiative indicating how Civil Aviation Technical College based at Sbia Libya in its march towards sustainable aviation is focusing on critical technologies like: (a) Integrated modeling of vehicles, atmospheric impact, and noise (b) optimization of new aircraft concepts and operations including environmental impact and (c) distributed, adaptive sensing and control. It treats sustainability is the way forward for aviation to …

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Energy flow bottlenecks in high voltage transmission lines known as congestions are one of the challenges facing power utilities in fast developing countries. Bottlenecks occur in selected power lines when transmission systems are operated at or beyond their transfer limits. In these cases, congestions result in preventing new power supply contracts, infeasibility in existing contracts, price spike and market power abuse. The “Superconductor Technology” in electric power transmission cables has been used as a solution to solve the problem of bottlenecks in energy transmission at high voltage underground cables and overhead lines. The increase in demand on power generation and transmission happening due to fast development and linked to the intensive usage of transmission network in certain points, which in turn, lead to often frequent congestion in getting the required power across to where it is needed

Dynamic loads of high capacity power grids under normal and severe conditions are the most concerns of system operators and dispatchers to maintain voltage stability. Reactive power (Q) are often drawn by loads from various generated sources disturbing the operational power factor. Compensating methods are used, depending on load types and their reactive power patterns, to continuously monitor and correctly counteract fast changes by extremely rapid VAR compensation especially during transient conditions. Using power electronics and combining both, power and control engineering, some FACTS devises equipped with selected power electronic switching are the appropriate methods to respond to system variations in almost no time. STATCOM regulates system voltages based on a voltage-source converters, by absorbing or generating reactive power. Contrary to a thyristor-based Static VAR

In certain extremely low probability, severe accident scenarios which have been postulated for liquid metal cooled fast reactors, large bubble cavities containing fuel vapor and fission products transit a layer of coolant and release this material to the cover gas thereby presenting a contribution to an accident-specific source term. So that a more mechanistic assessment of these types of events can be developed, analyses have recently been performed to account for the heat and work transfer observed in out-of-reactor source term experiments conducted during the 1980’s for oxide fueled reactors in the Fuel Aerosol Simulant Test (FAST) facility at Oak Ridge National Laboratory. In ten experiments, UO2 specimens were vaporized in pools of sodium, and for an additional number of benchmarking tests, in pools of water, for purposes of experimentally assessing the bubble transport characteristics of both types of pools. The current analyses present several firsts for these experiments: (a) a comparison of the bubble-to-coolant transfer rates; heat versus work, (b) a bubble-to-coolant heat transfer model accounting for how condensation and radiation heat transfer are affected by coolant selection; sodium versus water, and (c) an assessment of how both types of heat transfer influence the movement of aerosol-laden bubbles through the coolant pool. These analyses significantly extend previous evaluations of FAST experimental results by providing a more comprehensive model for determining how bubble-coolant interactions affect aerosol transport and, in this way, contribute to data base development associated with mechanistic assessments of the source term.

New composite polyvinyl alcohol (PVA)/polypropylene (PP) membranes were prepared by combining both solution electrospinning and melt electrospinning methods. Self‐designed and made needleless melt electrospinning device was used to fabricate PP membranes which acted as the support layer. PVA membrane on the surface was fabricated via solution electrospinning. The electrospun PVA/PP composite membranes were characterized by the pore size distribution, pure water flux, and rejection ratio, then compared with general composite membranes. Characterizations revealed that the fiber diameter of solution electrospun PVA membrane and melt electrospun PP membrane were 0.171 ± 0.027 and 2.24 ± 0.33 μm, respectively, and the average pore size was 0.832 μm and 27.29 μm, which was much smaller than the nonwoven membrane. The rejection ratio to the 500 nm particles of the PVA/PP …

Ad hoc underwater acoustic networks represent a very challenging field in digital communications due to the extreme nature of the underwater acoustic channel and also the requirement to meet critical needs in order to establish long range propagation, decentralisation and reliability. As a fact the underwater acoustic communications speed is five times less than the magnitude of the radio waves, and this makes the underwater acoustic suffer from high propagation delay and minimum throughput. This paper discusses the influence of the backoff windows on the ad hoc on demand Destination Sequenced Distance Vector (DSDV) protocol. Underwater Acoustic Media Access Control (UAMAC) is implemented in a NS2 simulator to adopt the Multiple Access Collision Avoidance and Acknowledgment (MACAW) scheme. The simulation results for the developed system are presented.