Extending P2PMesh: topology‐aware schemes for efficient peer‐to‐peer data sharing in wireless mesh networks

Wireless mesh networks (WMNs) have emerged as a promising technology that provides low‐cost broadband access to the Internet for fixed and mobile wireless end users. An orthogonal evolution in computer networking has been the rise of peer‐to‐peer (P2P) applications such as P2P data sharing. It is of interest to enable effective P2P data sharing in this type of networks. Conventional P2P data sharing systems are not cognizant of the underlying network topology and therefore suffer from inefficiency. We argue for dual‐layer mesh network architecture with support from wireless mesh routers for P2P applications. The main contribution of this paper is P2PMesh: a topology‐aware system that provides combined architecture and efficient schemes for enabling efficient P2P data sharing in WMNs. The P2PMesh architecture utilizes three schemes: (i) an efficient content lookup that mitigates traffic load imbalance at mesh routers; (ii) an efficient establishment of download paths; and (iii) a data transfer protocol for multi‐hop wireless networks with limited capacity. We note here that the path establishment and data transfer schemes are specific to P2P traffic and that other traffic would use routes determined by the default routing protocol in the WMN. Simulation results suggest that P2PMesh has the potential to improve the performance of P2P applications in a wireless multi‐hop setting; specifically, we focused on data sharing, but other P2P applications can also be supported by this approach. Copyright © 2011 John Wiley & Sons, Ltd.     

Active/passive control of sound radiation and power flow in fluid-loaded shells

The vibration and noise radiation from fluid-loaded cylindrical shells are controlled by using multiple stiffeners and passive constrained layer damping treatment. Dynamic and fluid finite elements are developed to study the fundamental phenomena governing the coupling between the stiffened shell, with and without damping, and the fluid domain surrounding it. The models are used to predict the response of the shell and to evaluate the effect of stiffening rings and damping treatment on both the structural vibration and noise radiation in the fluid domain. The geometry of the shell and fluid domain allows the formulation of a harmonic-based model, which uncouples the fluid–structural response of modes corresponding to different numbers of circumferential nodes.In this study, it is shown that stiffening of the shell reduces the amplitude of the vibration and noise radiation, particularly for high-order lobar modes. The attenuation of the shell response and sound radiation can be increased significantly through the application of passive constrained layer damping treatments on the inner surface of the stiffening rings.     

Optimizing Large-Scale Temporary Housing Arrangements after Natural Disasters

Natural disasters, such as hurricanes, earthquakes, and tsunamis often cause large-scale destruction in residential areas. In the aftermath of these disasters, emergency management agencies need to urgently develop and implement a temporary housing plan that provides displaced families with satisfactory and safe accommodations. This paper presents the computational implementation of a newly developed multiobjective optimization model to support decision-makers in emergency management agencies in optimizing large-scale temporary housing arrangements. The model is capable of simultaneously minimizing (1) postdisaster social and economic disruptions suffered by displaced families; (2) temporary housing vulnerabilities to postdisaster hazards; (3) adverse environmental impacts on host communities; and (4) public expenditures on temporary housing. The model is implemented in four main phases and it incorporates four optimization modules to enable optimizing each of the aforementioned important objectives. A large-scale temporary housing application example is presented to demonstrate the unique capabilities of the model and illustrate the performed computations in each of the implementation phases.     

Reactor thermal behaviors under kinetics parameters variations in fast reactivity insertion

The influences of variations in some of the kinetics parameters affecting the reactivity insertion are considered in this study, it has been accomplished in order to acquire knowledge about the role that kinetic parameters play in prompt critical transients from the safety point of view. The kinetics parameters variations are limited to the effective delayed neutron fraction (β_eff) and the prompt neutron generation time (Λ). The reactor thermal behaviors under the variations in effective delayed neutron fraction and prompt neutron generation time included, the reactor power, maximum fuel temperature, maximum clad temperature, maximum coolant temperature and the mass flux variations at the hot channel. The analysis is done for a typical swimming pool, plate type research reactor with low enriched uranium. The scram system is disabled during the accidents simulations. Calculations were done using PARET code. As a result of simulations, it is concluded that, the reactor (ETRR2) thermal behavior is considerably more sensitive to the variation in the effective delayed neutron fraction than to the variation in prompt neutron generation time and the fast reactivity insertion in both cases causes a flow expansion and contraction at the hot channel exit. The amplitude of the oscillated flow is a qualitatively increases with the decrease in both β_eff and Λ.     

Frame duplication and shuffling forgery detection technique in surveillance videos based on temporal average and gray level co-occurrence matrix

Multimedia Tools and Applications - Nowadays, due to the increasing crime and theft around the world, surveillance security systems play an important role. On the other hand, the availability of...     

Metal-Bound Methisazone; Novel Drugs Targeting Prophylaxis and Treatment of SARS-CoV-2, a Molecular Docking Study

SARS-CoV-2 currently lacks effective first-line drug treatment. We present promising data from in silico docking studies of new Methisazone compounds (modified with calcium, Ca; iron, Fe; magnesium, Mg; manganese, Mn; or zinc, Zn) designed to bind more strongly to key proteins involved in replication of SARS-CoV-2. In this in silico molecular docking study, we investigated the inhibiting role of Methisazone and the modified drugs against SARS-CoV-2 proteins: ribonucleic acid (RNA)-dependent RNA polymerase (RdRp), spike protein, papain-like protease (PlPr), and main protease (MPro). We found that the highest binding interactions were found with the spike protein (6VYB), with the highest overall binding being observed with Mn-bound Methisazone at −8.3 kcal/mol, followed by Zn and Ca at −8.0 kcal/mol, and Fe and Mg at −7.9 kcal/mol. We also found that the metal-modified Methisazone had higher affinity for PlPr and MPro. In addition, we identified multiple binding pockets that could be singly or multiply occupied on all proteins tested. The best binding energy was with Mn–Methisazone versus spike protein, and the largest cumulative increases in binding energies were found with PlPr. We suggest that further studies are warranted to identify whether these compounds may be effective for treatment and/or prophylaxis.     

Situational awareness of construction equipment using GPS, wireless and web technologies

Situational awareness refers to the ability by equipment operators to sense their environment with the objective of increasing safety and improving productivity on construction sites. This paper reports on research related to situational awareness of construction equipment using differential Global Positioning System (DGPS), wireless and web-based technologies. In this investigation, the researchers developed and implemented technologies for vehicle tracking, and collision detection. The paper concludes with a summary of these applications, along with a discussion of the limitations of current implementations, and the required augmentation by other technologies.