Increasing attention has been drawn to the development of Intelligent Transport Systems (ITSs) to realize the smart city vision. ITSs are expected to improve drivers' experience and safety in smart cities. Vehicular ad hoc networks, VANETs, are considered the building block as they connect between the system components? vehicles, Road Side Units (RSUs), traffic lights and management units. Connectivity is a major limitation in VANETs as it highly affects the system's performance due to the various challenges in the urban environment. In this paper, the basic routing protocols are presented to understand how routing is done. State of the art urban routing and clustering protocols are then surveyed to understand their impact on connectivity of urban VANETs. Open challenges to the network performance are summarized and possible solutions are proposed to overcome these challenges.
The vast amount of spectrum available at the underutilized millimeterwave (mmWave) band enables drastic increase in broadband cellular communication capacity and is considered as a key solution for future 5G mobile communications. Millimeter wave, ranging between 30 and 300 GHz, provides a solution for the bottleneck problem in the current cellular allocations, by offering orders of magnitude increase in the spectrum. This paper discusses the characteristics of the mmWave propagation channel, and highlights the main challenges associated with the use of mmWaves. The paper also outline the channel models proposed for mmWave communications. Beamforming techniques for millimeter wave communication are also described. Having an insight of the propagation environment is an essential requirement for developing future mmWave mobile systems.
The concept of Happiness and Positivity on an organizational level has witnessed a major shift. Being known for pursuing best practice, the UAE federal government has explored this concept and made it a reality through several initiatives to promote employee well being at work. This case study specifically explores an application of the Happiness & Positivity Survey from an internal communication perspective, highlighting the core opportunities and strategies implemented to ensure the successful implementation in a federal entity.
The focus of this study is ADEC kindergarten English teachers perceptions of teaching listening strategies used to help English Learners, the aim of this study is to identify the tools and approaches involved in delivering these strategies and the forms of assessment in children's listening comprehension, along with determining possible challenges and obstacles facing kindergarten teachers while applying these strategies in their classrooms. Structured questionnaire was used as an instrument in collecting the required data from target sample of participant. The results generated revealed that best strategies commonly used were incorporated songs and clapping as attentiongetting signals, in addition to performing body movement as reaction to simple instructions given by teachers. Commonly used assessments were mainly observations of children to check their listening comprehension and their level of following instructions. Finally, the results demonstrated that those kindergarten students who had not previously been exposed to English communication faced difficulties
Contracts are designed to govern the relations between business partners, allocate risk among them, and resolve conflicts that might arise during the course of the contract. Of course, a contract cannot resolve all conflicts as it cannot predict every possible scenario and hence, dispute resolution mechanisms have been developed to assist. Arbitration, among these mechanisms, is considered the most efficient legally binding dispute resolution mechanism. Arbitration efficiency is nothing, but an agreed flexibility in the applied rules and procedures. Among this flexibility, arbitration rules of evidence admissibility that are very much decided by the arbitral tribunal. This paper reviews the famous arbitration rules in an attempt to find common grounds with respect to evidence admissibility. It further proposes a framework to unify the approach of assessing evidence admissibility by the arbitral tribunal.
There is a space for more extensive adoption of spintronic devices in biological applications. Giant magnetoresistance spintronic devices, for example, can act as magnetic sensors for metallic labeled substances. This can promote detection and manipulation of biological cells. Promising applications for spintronics are not limited to inorganic material as new investigations have shown the possibilities of using organic material as spintronic polarizers. In this paper, we give a general overview about inorganic and organic spintronic applications, and describe futuristic trends.
In this work, 3nmthick ZincOxide (ZnO) nanoislands are deposited by Atomic Layer Deposition (ALD). UVVisNIR and XPS measurements show that the nanostructures show quantum confinement effects in 1D where the bandgap is increased and the electron affinity is reduced. In addition, nonvolatile MOS memory devices with ZnO nanoislands trapping layer are studied are fabricated by a single ALD step and analyzed using highfrequency CV measurements. The devices showed a large memory window at low operating voltages with excellent retention and endurance characteristics due to the additional oxygen vacancies in the nanoislands and the deep barrier for the trapped holes due to the reduction in ZnO electron affinity. The results prove that the ZnO nanoislands are promising in future low power memory applications.
Nanomaterials are a class of materials with dimensions on the nanometer scale. Nanomaterials are attracting great interest for applications in medicine, electronics and energy, among other fields. As they become more popular and more widely produced, it will be important to better understand the interaction between living tissue and nanomaterials. This paper reviews several recent studies on safety and biocompatibility of nanoparticles and carbon nanotubes. It is observed that many materials described as inert or biocompatible on a macroscale setting may not be as safe at the nanoscale. From these observations, some preliminary decisions can be made on the future of certain nanomaterials.
Single and double slot waveguides based on a silicononinsulator platform were numerically studied using fullvectorial finite difference eigenmode solver.The spatial Efield profile and distribution at the waveguide crosssection were determined for the fundamental TE mode at 1.55 ?m wavelength. The power confinement factor and the average normalized intensity inside the slot region were investigated as a function of the slot and slab widths. For the single slot waveguide, the slot and slab widths were varied from 10 nm to 250 nm and from 100 nm to 250nm, respectively. For the dual slot waveguide, the central slab was varied from 50 nm to 250 nm.
This paper presents an experimental study on a twophase airwater flow in a microVenturi channel. The influence of the flow control parameters such as water pressure and air flow rate, on the controlled generation of microbubbles, are investigated. Experiments were conducted in a transparent microVenturi channel having a depth of 40 ?m. When the inlet flow control parameters were varied, significant changes were observed on the microbubble velocity, size and frequency. Image analysis, focused on vena contracta, showed that the velocity of generated microbubbles decrease suddenly to reach a constant value of 0.25 m/s. The bubble area is measured, having a constant value in time even if its shape is changed. Bubble size depend strongly on air mass flow rate. For different inlet flow parameters, the bubble frequency is increasing linearly with respect to the increasing air mass flow rates.
