Graph-Based Radio Resource Sharing Schemes for MTC in D2D-based 5G Networks

Apart from the the increasing demand of smartphones in human-to-human (H2H) communications, the introduction of machine-to-machine (M2M) devices poses significant challenges to wireless cellular networks. In order to offer the ability to connect billion of devices to propel the society into a new era of connectivity in our homes, officies and smart cities, we design novel radio resource sharing algorithms in a H2H/M2M coexistence case to accommodate M2M communications while not severely degrading existing H2H services. We propose group-based M2M communications that share the same spectrum with H2H communications through device-to-device (D2D) communication, as one of the technology components of 5G architecture. First, we formulate radio resource sharing problem as a sum-rate maximization, problem for which the optimal solution is non-deterministic polynomial-time hard (NP-hard). To overcome the computational complexity of the optimal solution, we model the resource sharing problem as a bipartite graph, then propose a novel interference-aware graph-based resource sharing scheme using a fixed M2M transmit power. To further enhance the protection of H2H services, we introduce an adaptive power control mechanism into the interference-aware graph-based resource sharing scheme. M2M transmit power is efficiently adjusted using one among the two following alternative controllers, namely, either the proportional integral derivative (PID) or the fuzzy logic. The latter is proposed within the aim to assure the desired quality-of-service (QoS) of H2H users and increase the efficiency of M2M spectrum usage. In both cases (fixed and adaptive), a centralized and a semi-distributed instantiations are given. Simulation results show that adaptive M2M radio resource sharing scheme using fuzzy logic is the one that achieves the best compromise. In fact, it guarantees H2H performance in terms of throughput and fairness while maximizing the efficiency of M2M spectrum usage. Simulation results also show that in spite of its quite good performance, semi-distributed M2M resource sharing instantiation achieves them with a decline of up to 10% in terms of H2H throughput compared to the centralized instantiation. This is achieved through a markedly lower communication overhead.

     

Machining and Ceramic/Ceramic Joining to Form Internal Mesoscale Channels

Ceramics and semiconducting materials with internal channels are crucial in a variety of diverse technologies such as "lab on a chip," fuel cell applications, and cooling of microelectronics. In this paper, techniques for fabricating internal channels in brittle materials first are reviewed. Then, the mechanical machining of surface channels in 99.99% pure alumina partially sintered at 600°C and 700°C is discussed. After machining, the partially sintered alumina is sintered to a density of about 97% of theoretical and then joined to 96% pure alumina to convert the surface channels into internal channels.     

Intelligent antenna selection decision in IEEE 802.15.4 wireless sensor networks: An experimental analysis

The goal of this paper is to study the feasibility of making intelligent antenna selection decision in IEEE 802.15.4 Wireless Sensor Networks (WSNs). This study provides us the basis to design and implement software defined intelligent antenna switching capability to wireless sensor nodes based on Received Signal Strength Indicator (RSSI) link quality metric. First, we discuss the results of our newly designed radio module (Inverted-F Antenna) for 2.4 GHz bandwidth (WSNs). Second, we propose an intelligent antenna selection strategy to exploit antenna diversity. Third, we propose the prototype of our diversity antenna for the TelosB mote and the intelligent switch design. Finally, we compare the performance of the built-in TelosB antenna with our proposed external antenna in both laboratory and realistic environments. Experimental results confirm the gain of 6–10 dB of the proposed radio module over the built-in radio module of the TelosB motes.     

Smart dynamic evacuation planning and online management using vehicular communication system

During disasters, swiftly and efficiently evacuating populations in hazardous situations is crucial to minimize losses. This study proposes a novel framework to address dynamic population evacuation (DPE) problems, which includes planning and online evacuation management phases facilitated by vehicular communication. In the planning phase, a shelter allocation problem (SAP) is solved dynamically for destination choice and a dynamic traffic assignment (DTA) for path choice toward the chosen destinations to obtain an initial evacuation plan. The initial plan is then enhanced by employing a vehicular ad hoc network (VANET) within the vehicular edge computing (VEC) architecture. This enhancement enables communication among evacuees, allowing them to revise their vehicle's route choice and planned destination. These revisions take into account the changing risk and traffic conditions. The proposed online DPE framework is applied to the real evacuation scenario of Mill Valley City, CA. The proposed model is evaluated with different VANET architectures, including vehicular cloud computing (VCC) and VEC. The results show that the VEC framework outperforms other configurations and improves the evacuation process compared to the scenario with an initial plan by more than 30% in network clearance time. Additionally, a performance analysis is carried out for evacuation scenarios with different penetration rates of connected vehicles in VANET.     

Diamond-Like Carbon - Coated Silicon Nanowires as a Supercapacitor Electrode in an Aqueous LiClO4 Electrolyte

Silicon - Silicon nanowires (SiNWs) were successfully coated by uniform, adherent, and homogenous films of diamond-like carbon (DLC) using electrophoretic method. The coating was performed in an...     

A Secure Mechanism Design-Based and Game Theoretical Model for MANETs

To avoid the single point of failure for the certificate authority (CA) in MANET, a decentralized solution is proposed where nodes are grouped into different clusters. Each cluster should contain at least two confident nodes. One is known as CA and the another as register authority RA. The Dynamic Demilitarized Zone (DDMZ) is proposed as a solution for protecting the CA node against potential attacks. It is formed from one or more RA node. The problems of such a model are: (1) Clusters with one confident node, CA, cannot be created and thus clusters’ sizes are increased which negatively affect clusters’ services and stability. (2) Clusters with high density of RA can cause channel collision at the CA. (3) Clusters’ lifetime are reduced since RA monitors are always launched (i.e., resource consumption). In this paper, we propose a model based on mechanism design that will allow clusters with single trusted node (CA) to be created. Our mechanism will motivate nodes that do not belong to the confident community to participate by giving them incentives in the form of trust, which can be used for cluster’s services. To achieve this goal, a RA selection algorithm is proposed that selects nodes based on a predefined selection criteria function and location (i.e., using directional antenna). Such a model is known as moderate. Based on the security risk, more RA nodes must be added to formalize a robust DDMZ. Here, we consider the tradeoff between security and resource consumption by formulating the problem as a nonzero-sum noncooperative game between the CA and attacker. Finally, empirical results are provided to support our solutions.     

Kinetics and Mechanism of the Water–Gas Shift Reaction Over Platinum Supported Catalysts

A dual-site reaction mechanism is proposed for Pt based water–gas shift catalysts. The sorption equilibrium parameters are evaluated in detail to validate their physical significance. The values of the van ‘t Hoff parameters for CO and H₂ correspond to those for chemisorption on platinum. The sorption parameters of H₂O and CO₂ on the supports have been quantitatively determined from temperature-programmed desorption experiments and have been compared to the values obtained from the kinetic study. Finally the proposed model is able to explain the different activities between the two catalysts.     

Design of an H∞ controller for the Delta robot: experimental results

This paper deals with an efficient implementation of an H∞ multi-variable controller on the three degrees of freedom (DOF) parallel robot namely the ‘Delta robot’. The H∞ controller is designed by the mixed sensitivity approach in which the sensitivity function matrix S and the complementary sensitivity function matrix T are taken into account. For this purpose, a nonlinear analytical dynamic state model is developed and a tangent linearization procedure is used to obtain a multi-variable linear model around a functional point. Real-time experiments were performed to compare the centralized H∞ controller with a classical decentralized Proportional Integral Derivative (PID) controller. Experimental tracking results show that the performances of the PID compared to those of the H∞ decrease when the movement dynamic is increased. At high dynamic (12 Ge), it is shown that the maximum tracking error and the error around the stop positions of the H∞ are, respectively, 80 and 60% of the PID. The experiments of the load variation have proven that the H∞ is more robust than the PID. The steady-state root mean square error of the H∞ is less than 60% of the one obtained using the PID controller.     

Enhancement of Electrochemical Capacitance of Silicon Nanowires Arrays (SiNWs) by Modification with Manganese Dioxide MnO2

Silicon - Silicon nanowire arrays (SiNWs) were fabricated by one-step metal-assisted chemical etching process and modified with MnO2 nanoparticles by a chemical electroless method. Scanning...     

Building Model of Photovoltaic Cell Module with MATLAB Simulink

In this paper, a PV （photovoltaic） module in renewable energy conversion system is simulated. The simulation of the system is developed using MATLAB/Simulink environments, which can be representative of PV cell, module and array for easy use on simulation block. The PV model is developed using basic circuit equations of the photovoltaic solar cells including the effects of irradiation and temperature. The output current and power characteristics of PV model are simulated. The results are provided and presented here.