Relay Delay Research Articles

Centralized multicasting AODV routing protocol optimized for intermittent cognitive radio ad hoc networks

The advancement of wireless technology is affected by Spectrum scarcity and the overcrowding of free spectrum. Cognitive Radio Ad Hoc Networks (CRAHNs) have emerged as a possible solution to both the scarcity and overcrowding challenges of the spectrum. The CRAHNs ensure that the Secondary Users (SUs) do co-exist with Primary Users (PUs) in a non-interfering manner. The SUs access the licensed spectrum opportunistically when they are idle. CRAHNs have many use cases which include intermittent networks here referred to as intermittent CRAHNs (ICRAHNs). For example, the Military (MCRAHNs). MCRAHN is complex and characterized by a dynamic topology which is subject to frequent partitioning and route breakages due to attacks and destruction in combat. This study optimizes the routing protocols for intermittent networks such as the MCRAHNs. ICRAHN routing is a challenge due to the network’s intermittent attribute, which is subject to destruction in the case of MCRAHN which is characterized by frequent link breakages. To better understand the routing in this network scenario, this paper presents two analytic models for the AODV and MAODV protocols based on queuing theory. The analytic models simulate unicast and multicast AODV in terms of factors such as queuing delay, throughput, and network scalability. Numerical analysis shows that MAODV outperforms AODV. Furthermore, the suggested routing protocols' performance was tested using network simulations utilizing the following metrics: throughput, Routing Path delay, Node Relay delay, and Spectrum Mobility delay. The simulation findings suggest that the MAODV protocol outperforms the AODV protocol.

Development of energy conversion and lightning strike protection simulation for photovoltaic-wind turbine on grid

Photovoltaic (PV) installations and wind turbines that are installed on the rooftops of buildings need to be protected because the layout is in a high position and there is a risk of being struck by lightning. Therefore, a more effective protection system is designed to anticipate electronic damage and fire on all materials in the distribution network, especially the addition of PV and wind turbine installations on building roofs. The purpose of this study is to simulate a lightning protection system on the distribution network and the results of on-grid PV energy conversion using electrical transient analyzer program (ETAP) software. Feeder relay delay times and cascade coordination patterns between outgoing and incoming relays do not overlap. the delay time of the relay working on the feeder is 0.31 s and the coordination pattern of the outgoing relay and incoming relay does not touch each other, so the delay time for the incoming relay is 2.73 s. Then testing the results of PV energy conversion connected to the grid using MATLAB Simulink monitoring obtained data reaching 1.600 Wp at peak power with sun conditions parallel to the PV installation layout.

Design a Chicken Coop Monitoring System Based on the Internet of Things

Internal and external factors greatly influence the optimal breeding of chickens in the maintenance of chickens, with temperature and humidity being one of the external factors that greatly influences. Improper ambient temperature can cause losses to the chicken farmer as well as a decrease in productivity, while in practice it is necessary to monitor or check the control consistently to monitor the temperature of the coop. Temperature and humidity monitoring manually are less efficient, so the tools in this study aim to help farmers to facilitate monitoring that can be done through devices with accurate results. This tool is assisted by a DHT11 sensor, lamps, fans, and LCD in temperature monitoring. supported by the application of IoT, which makes it easier to monitor via devices. Test results on components and software show that all devices and software can function as they should. The data from the experimental test results of 15 tests conducted in the laboratory indicate that the tool can detect an average relay delay time of 1 of 0.836 seconds, the lamp in response to the temperature drop of 1.271 seconds, the delay from relay 2 by 0.466 seconds, and the fan in response to the temperature increase of 0.596 seconds.

Spectrum-Aware Transitive On-Demand Routing Protocol for Military Cognitive Radio Ad Hoc Networks

The advancement of wireless technology is increasing the demand for scarce spectrum. Cognitive radio ad hoc networks (CRAHNs) were proposed as a solution to spectrum scarcity which is also deployed in combat. However, military cognitive radio ad-hoc networks (MCRAHNs) are subject to destruction and frequent link breakages. The challenge with MCRAHNs routing is the timing-out of packets. This paper proposes the spectrum-aware transitive multi-cast on-demand distance vector (SAT-MAODV), optimised for throughput and delay. The relay nodes are selected based on zonal data and mobility. This is achieved through handshaking and sharing of location data. The nodes are expected to store location data of nodes encountered, which is used in routing and in determining the movement of the node. The mobility of military nodes is organised and structured, which simplifies routing. The SAT-MAODV was evaluated in network simulator 2 and the results show that the scheme is effective. UsingSAT-MAODV instead of xWCETT reduced routing path and node relay delay by at least 65% and 13% respectively, and increased achievable throughput by 31%. It also improved the delivery ratio by 9% while reducing latency by 27% in comparison with MARSA.

MODELING TO IMPROVE THE PERFORMANCE OF REVERSE POWER RELAY IN GENERATOR

The generator is the primary component in electricity generation and requires a protection system from internal and external interference that occurs. This study considers how to improve the performance of relays in power plants. A model of a generator that is executed in a fault condition to reset the protective equipment, namely Reverse Power Relay (RPR). The study is intended to model the state of internal and external fault on the generator by applying a working principle of RPR. The model is designed to anticipate the actual fault in the generator. The simulation results obtained output such as; active power, current and time delay relay. The RPR reset of the generator system is applied to the generator in Riau Power. The RPR is installed on the generator is -612 kW, equivalent to 30%, the relay delay time is 0.2 seconds. Based on standardization, the return of power reaches a maximum of -12.66 MW, which is captured 50% with a maximum replacement of 30 seconds. Results of the RPR simulation have been validated with the IEEE standard at a time delay that corresponds to the percentage of reverse power settings installed at 6% and a time delay of 0.6%. Finally, to maximize the protection system on the generator, adjust 50% to 95% of the installed settings. It can be said that the system is able to increase generator protection and minimize the impact of internal or external fault.

Network Layer Aspects of Permissionless Blockchains

Permissionless blockchains reach decentralized consensus without requiring pre-established identities or trusted third parties, thus enabling applications such as cryptocurrencies and smart contracts. Consensus is agreed on data that is generated by the application and transmitted by the system’s (peer-to-peer) network layer. While many attacks on the network layer were discussed so far, there is no systematic approach that brings together known attacks, the requirements, and the design space of the network layer. In this paper, we survey attacks on the network layer of permissionless blockchains, and derive five requirements: 1) performance; 2) low cost of participation; 3) anonymity; 4) DoS resistance; and 5) topology hiding. Furthermore, we survey the design space of the network layer and qualitatively show the effect of each design decisions on the fulfillment of the requirements. Finally, we pick two aspects of the design space, in-band peer discovery and relay delay, and demonstrate possible directions of future research by quantitatively analyzing and optimizing simplified scenarios. We show that while most design decisions imply certain tradeoffs, there is a lack of models that analyze and formalize these tradeoffs. Such models could aid the design of the network layer of permissionless blockchains. One reason for the lack of models is the deliberately limited observability of deployed blockchains. We emphasize that simulation based approaches cope with these limitations and are suited for the analysis of the network layer of permissionless blockchains.

Multihop Cellular Networks: Dynamic Channel Assignment and Routing Protocol for Improving Performance

Multihop cellular Networks has the problem of channel assignment when connections are established between the adjacent cells and due to more number of nodes in the path between the sender and the receiver relay delay occurs and cause unwanted delay in the overall end to end communication. To overcome the problems associated with the relay delay and the overall performance in the Multihop Cellular Networks a new protocol is introduced which combines the merits of both the modified Minimum Slot Waiting First Algorithm and the modified Distance Vector Routing. Through the proposed new protocol, we can provide solution for the problem of routing and relay delay in Multihop Cellular Networks and the performance of the packet transmission can be improved.

Design, Optimization, and Scaling of MEM Relays for Ultra-Low-Power Digital Logic

Microelectromechanical relays have recently been proposed for ultra-low-power digital logic because their nearly ideal switching behavior can potentially enable reductions in supply voltage (Vdd) and, hence, energy per operation beyond the limits of MOSFETs. Using a calibrated analytical model, a sensitivity-based energy-delay optimization approach is developed in order to establish simple relay design guidelines. It is found that, at the optimal design point, every 2 X energy increase can be traded off for a ~1.5x reduction in relay delay. A contact-gap-to-actuation-gap thickness ratio of 0.7-0.8 is shown to result in the most energy-efficient relay operation, implying that pull-in operation is preferred for an energy-efficient relay design. Based on the analytical model and design guidelines, a scaling theory for relays is presented. A scaled relay technology is projected to provide >; 10 X energy savings over an equivalent MOSFET technology, for circuits operating at clock frequencies up to ~100 MHz.

Dual chemotaxis signalling regulates Dictyostelium development: Intercellular cyclic AMP pulses and intracellular F-actin disassembly waves induce each other

Aggregating Dictyostelium discoideum amoebae periodically emit and relay cAMP, which regulates their chemotaxis and morphogenesis into a multicellular, differentiated organism. Cyclic AMP also stimulates F-actin assembly and chemotactic pseudopodium extension. We used actin-GFP expression to visualise for the first time intracellular F-actin assembly as a spatio-temporal indicator of cell reactions to cAMP, and thus the kinematics of cell communication, in aggregating streams. Every natural cAMP signal pulse induces an autowave of F-actin disassembly, which propagates from each cell's leading end to its trailing end at a linear rate, much slower than the calculated and measured velocities of cAMP diffusion in aggregating Dictyostelium. A sequence of transient reactions follows behind the wave, including anterior F-actin assembly, chemotactic pseudopodium extension and cell advance at the cell front and, at the back, F-actin assembly, extension of a small retrograde pseudopodium (forcing a brief cell retreat) and chemotactic stimulation of the following cell, yielding a 20 s cAMP relay delay. These dynamics indicate that stream cell behaviour is mediated by a dual signalling system: a short-range cAMP pulse directed from one cell tail to an immediately following cell front and a slower, long-range wave of intracellular F-actin disassembly, each inducing the other.

Robust sliding mode control of non-linear systems with delay: a design via polytopic formulation

This paper outlines the possibility to control non-linear uncertain systems with single, possibly time-varying state-delay. These systems are submitted to additive perturbations (possibly non-vanishing). The control is of sliding mode type and the sliding surface is designed to maximize the calculable set of delays which do not destabilize the relay–delay system. The way to deal with the non-linear parts of the model relies on a polytopic formulation, i.e. a decomposition into a non-linear combination of linear models, whose weighting coefficients satisfy a convex property. The conditions for the existence of the sliding regime are studied by using both a Lyapunov–Krasovskii functional and a Lyapunov–Razumikhin function. The optimization procedure for the choice of the sliding surface is expressed in terms of LMIs. An example illustrates the proposed method.

Stabilization of amplitude of oscillations via relay delay control

Time delay does not allow realizing an ideal sliding mode, but implies oscillations in the state space. It is shown that relay delay controllers allow us to achieve stabilization for amplitude of oscillations suppressing uncertainties in a time delay even in the case when the time delay is variable. Sufficient conditions for a relay delay stabilization are found. The obtained results are illustrated in the example of the relay delay stabilization for the inverted pendulum.