Computational study on shear strengthening of RC continuous beams using CFRP sheet

This research studied the feasibility and effectiveness of a new method of strengthening existing RC continuous beams in shear by using CFRP strips. The CFRP composite strips were used to strengthen concrete externally at a known failure plane to resist shear stresses in shear friction. All beams were design to fails in shear with av/d 2.5. This research describes the computational study on shear strengthening of RC continuous beams using CFRP strips. In this study, a computational program consisting of 5 beams were performed subjected to experimental program with the same size and details of the beams where the experimental study was performed by other student in the laboratory. Here in this part the study done through simulation by ABAQUS Software version 6.9. Therefore, this research aims to investigate the effectiveness of using externally bonded CFRP strips in repair and strengthen of RC continuous beams and also to know the behavior of RC continuous beams strengthened in shear with CFRP sheet. So in this study there are five specimens with different CFRP wrapping scheme as 90 degree and 45 degree with three sides and four sides each beam. The computational results were compare with the experimental results that obtained by other student. The computational results show great agreement with the experimental results

Efficient and Privacy-Preserving Ride Sharing Organization for Transferable and Non-Transferable Services

Ride-sharing allows multiple persons to share their trips together in one vehicle instead of using multiple vehicles. This can reduce the number of vehicles in the street, which consequently can reduce air pollution, traffic congestion and transportation cost. However, a ride-sharing organization requires passengers to report sensitive location information about their trips to a trip organizing server (TOS) which creates a serious privacy issue. In addition, existing ride-sharing schemes are non-flexible, i.e., they require a driver and a rider to have exactly the same trip to share a ride. Moreover, they are non-scalable, i.e., inefficient if applied to large geographic areas. In this paper, we propose two efficient privacy-preserving ride-sharing organization schemes for Non-transferable Ride-sharing Services (NRS) and Transferable Ride-sharing Services (TRS). In the NRS scheme, a rider can share a ride from its source to destination with only one driver whereas, in TRS scheme, a rider can transfer between multiple drivers while en route until he reaches his destination. In both schemes, the ride-sharing area is divided into a number of small geographic areas, called cells, and each cell has a unique identifier. Each driver/rider should encrypt his trip's data and send an encrypted ride-sharing offer/request to the TOS. In NRS scheme, Bloom filters are used to compactly represent the trip information before encryption. Then, the TOS can measure the similarity between the encrypted trips data to organize shared rides without revealing either the users' identities or the location information. In TRS scheme, drivers report their encrypted routes, an then the TOS builds an encrypted directed graph that is passed to a modified version of Dijkstra's shortest path algorithm to search for an optimal path of rides that can achieve a set of preferences defined by the riders

Advanced scientific irrigation management

Presented at Meeting irrigation demands in a water-challenged environment: SCADA and technology: tools to improve production: a USCID water management conference held on September 28 - October 1, 2010 in Fort Collins, Colorado.Includes bibliographical references.Efficient drip irrigation of 10,000,000 fast-growing Pacific Albus trees in the water-challenged environment of Easter Oregon, US; requires not only a massive and complex computerized water distribution system but also an efficient and economical methodology to manage and deliver the water to the trees. The Greenwood Resources Boardman Tree Farm (GWR BTF) achieves this by interacting its Advanced Scientific Irrigation Management (ASIM) program with its state-of-art Irrigation Supervisory Control and Data Acquisition (I-SCADA) system to achieve high irrigation and economical efficiencies. Also within this ASIM / I-SCADA system combination is an elaborate automated soil moisture sensing operation and an original and innovative methodology incorporating a customized Advance Hydraulic Balanced Irrigation Scheduling (AHBIS) program, which enables smooth and steady hydraulic operation of 101 pumps at 23 major pump stations. Additionally, the BTF I-SCADA system operates pivot irrigation on 1,930 hectares (4,770 ac) of very high-value agriculture crops, including organic crops. Boardman Tree Farm offers a show-case example where the latest technology and human ingenuity are utilized to drip irrigate vast areas of land, while at the same time minimizing the use of scarce water and energy resources and maintaining a sustainable and economical rate of fiber production for use in BioEnergy, Paper and Solid Wood production

Performance evaluation of synchronous reluctance motors with and without permanent magnets

Nowadays, a growing interest in the efficiency and the cost of electrical machines has been noticed. Therefore, Synchronous Reluctance Motors (SynRMs) have become more attractive, thanks to their higher efficiency and nevertheless acceptable cost compared to induction machines. The rotor design of SynRMs with or without permanent magnets (PMs) has a huge effect on the motor efficiency, torque density and power factor. This paper introduces an evaluation for the performance of SynRMs with and without PMs in terms of efficiency, torque and power factor maps. Three different rotor designs for the same machine have been compared. For one machine, the experimental measurements have been obtained and the validation of the simulation results have been confirme

Performance comparison of conventional synchronous reluctance machines and PM-assisted types with combined star-delta winding

This paper compares four prototype Synchronous Reluctance Motors (SynRMs) having an identical geometry of iron lamination stacks in the stator and rotor. Two different stator winding layouts are employed: a conventional three-phase star connection and a combined star-delta winding. In addition, two rotors are considered: a conventional rotor without magnets and a rotor with ferrite magnets. The performance of the four SynRMs is evaluated using a two-dimensional (2D) Finite Element Model (FEM). For the same copper volume and current, the combined star-delta-connected stator with Permanent Magnets (PMs) in the rotor corresponds to an approximately 22% increase in the output torque at rated current and speed compared to the conventional machine. This improvement is mainly thanks to adding ferrite PMs in the rotor as well as to the improved winding factor of the combined star-delta winding. The torque gain increases up to 150% for low current. Moreover, the rated efficiency is 93.60% compared to 92.10% for the conventional machine. On the other hand, the impact on the power factor and losses of SynRM when using the star-delta windings instead of the star windings is merely negligible. The theoretical results are experimentally validated using four identical prototype machines with identical lamination stacks but different rotors and winding layouts

Geotechnical Behaviour of Reinforced Soft Clay by Marble Dust as a Waste Material

Civil engineers around the world are in search of new alternative resources which are required both for cost-effective solutions for ground improvement and conservation of scarce natural resources. The various methods of ground improvement currently in use include lime columns, stone columns, use of chemical stabilizers, and various kinds of inclusions like metal strips, mats, fibres, geosynthetics, etc. The cost of these virgin materials as well as the processes involved is usually high and as such, they are yet to be commonly used in developing foundation performances. This paper illustrates the application of using marble dust stabilization in improving the soft clay soil. Various tests with different marble dust contents were performed to study the effect of using material as a stabilizing technique on main geotechnical soft clay properties. A series of laboratory tests like plasticity and consolidation at a different percentage of marble dust has been done. These experiments showed that the addition of marble dust resulting in composites hardens material which reduced the plasticity and compressibility parameters of the reinforced soft clay. The induction of reinforced composite material successfully decreases and adsorbs the excess water inside the soft clay thus, modifying the soft clay plasticity and significantly increase the soft clay stiffness and decrease the settlement. The used marble dust reducing the volumetric shrinkage and produced isotropic compressible ductile material with less settlement and higher shear strength. This adopted method will be applied to unravel the geotechnical stabilization issues, for instance, road embankments modification and foundation use

Geotechnical Behaviour of Reinforced Soft Clay by Marble Dust as a Waste Material

Civil engineers around the world are in search of new alternative resources which are required both for cost-effective solutions for ground improvement and conservation of scarce natural resources. The various methods of ground improvement currently in use include lime columns, stone columns, use of chemical stabilizers, and various kinds of inclusions like metal strips, mats, fibres, geosynthetics, etc. The cost of these virgin materials as well as the processes involved is usually high and as such, they are yet to be commonly used in developing foundation performances. This paper illustrates the application of using marble dust stabilization in improving the soft clay soil. Various tests with different marble dust contents were performed to study the effect of using material as a stabilizing technique on main geotechnical soft clay properties. A series of laboratory tests like plasticity and consolidation at a different percentage of marble dust has been done. These experiments showed that the addition of marble dust resulting in composites hardens material which reduced the plasticity and compressibility parameters of the reinforced soft clay. The induction of reinforced composite material successfully decreases and adsorbs the excess water inside the soft clay thus, modifying the soft clay plasticity and significantly increase the soft clay stiffness and decrease the settlement. The used marble dust reducing the volumetric shrinkage and produced isotropic compressible ductile material with less settlement and higher shear strength. This adopted method will be applied to unravel the geotechnical stabilization issues, for instance, road embankments modification and foundation use