Wired Networks Research Articles

English

Proper traffic simulation of electric vehicles, which draw energy from overhead wires, requires adequate modeling of traction infrastructure. Such vehicles include trains, trams or trolleybuses. Since the requested power demands depend on a traffic situation, the overhead wire DC electrical circuit is associated with a non-linear power flow problem. Although the Newton-Raphson method is well-known and widely accepted for seeking its solution, the existence of such a solution is not guaranteed. Particularly in situations where the vehicle power demands are too high (during acceleration), the solution of the studied problem may not exist. To deal with such cases, we introduce a numerical method which seeks maximal suppliable power demands for which the solution exists. This corresponds to introducing a scaling parameter to reduce the demanded power. The interpretation of the scaling parameter is the amount of energy which is absent in the system, and which needs to be provided by external sources such as on-board batteries. We propose an efficient two-stage algorithm to find the optimal scaling parameter and the resulting potentials in the overhead wire network. We perform a comparison with a naive approach and present a real-world simulation in the part of the Pilsen city in the Czech Republic. These simulations are performed in the traffic micro-simulator SUMO, a popular open-source traffic simulation platform.

Electromagnetic Scattering by Networks of High-Permittivity Thin Wires

The electromagnetic scattering from interconnections of high-permittivity dielectric thin wires with sizes smaller than (or almost equal to) the operating wavelength is investigated. A simple lumped element model for the polarization current intensities induced in the wires is proposed. The circuit elements are capacitances and inductances between the wires. An analytical expression for the induced polarization currents in terms of the magneto-quasistatic current modes is obtained. The connection between the spectral properties of the loop inductance matrix and the network's resonances is established. The number of the allowed current modes and resonances is deduced from the topology of the circuit's digraph. The coupling to radiation is also included, and the radiative frequency shifts and the quality factors are derived. The introduced concept and methods may find applications both at the microwaves and in nanophotonics.

Sex-specific signatures of intrinsic hippocampal networks and regional integrity underlying cognitive status in multiple sclerosis.

The hippocampus is an anatomically compartmentalized structure embedded in highly wired networks that are essential for cognitive functions. The hippocampal vulnerability has been postulated in acute and chronic neuroinflammation in multiple sclerosis, while the patterns of occurring inflammation, neurodegeneration or compensation have not yet been described. Besides focal damage to hippocampal tissue, network disruption is an important contributor to cognitive decline in multiple sclerosis patients. We postulate sex-specific trajectories in hippocampal network reorganization and regional integrity and address their relationship to markers of neuroinflammation, cognitive/memory performance and clinical severity. In a large cohort of multiple sclerosis patients (n = 476; 337 females, age 35 ± 10 years, disease duration 16 ± 14 months) and healthy subjects (n = 110, 54 females; age 34 ± 15 years), we utilized MRI at baseline and at 2-year follow-up to quantify regional hippocampal volumetry and reconstruct single-subject hippocampal networks. Through graph analytical tools we assessed the clustered topology of the hippocampal networks. Mixed-effects analyses served to model sex-based differences in hippocampal network and subfield integrity between multiple sclerosis patients and healthy subjects at both time points and longitudinally. Afterwards, hippocampal network and subfield integrity were related to clinical and radiological variables in dependency of sex attribution. We found a more clustered network architecture in both female and male patients compared to their healthy counterparts. At both time points, female patients displayed a more clustered network topology in comparison to male patients. Over time, multiple sclerosis patients developed an even more clustered network architecture, though with a greater magnitude in females. We detected reduced regional volumes in most of the addressed hippocampal subfields in both female and male patients compared to healthy subjects. Compared to male patients, females displayed lower volumes of para- and presubiculum but higher volumes of the molecular layer. Longitudinally, volumetric alterations were more pronounced in female patients, which showed a more extensive regional tissue loss. Despite a comparable cognitive/memory performance between female and male patients over the follow-up period, we identified a strong interrelation between hippocampal network properties and cognitive/memory performance only in female patients. Our findings evidence a more clustered hippocampal network topology in female patients with a more extensive subfield volume loss over time. A stronger relation between cognitive/memory performance and the network topology in female patients suggests greater entrainment of the brain’s reserve. These results may serve to adapt sex-targeted neuropsychological interventions.

Secure and dynamic access control for the Internet of Things (IoT) based traffic system.

Today, the trend of the Internet of Things (IoT) is increasing through the use of smart devices, vehicular networks, and household devices with internet-based networks. Specifically, the IoT smart devices and gadgets used in government and military are crucial to operational success. Communication and data sharing between these devices have increased in several ways. Similarly, the threats of information breaches between communication channels have also surged significantly, making data security a challenging task. In this context, access control is an approach that can secure data by restricting unauthorized users. Various access control models exist that can effectively implement access control yet, and there is no single state-of-the-art model that can provide dynamicity, security, ease of administration, and rapid execution all at once. In combating this loophole, we propose a novel secure and dynamic access control (SDAC) model for the IoT networks (smart traffic control and roadside parking management). Our proposed model allows IoT devices to communicate and share information through a secure means by using wired and wireless networks (Cellular Networks or Wi-Fi). The effectiveness and efficiency of the proposed model are demonstrated using mathematical models and discussed with many example implementations.

Nematic order driven by superconducting correlations

The interplay of nematicity and superconductivity has been observed in a wide variety of quantum materials. To explore this interplay, we consider a two-dimensional (2D) array of nematogens, local droplets with Z3 nematicity, coupled to a network of Josephson junction wires. Using finite temperature classical Monte Carlo simulations, we elucidate the phase diagram of this model and show that the development of superconducting correlations and the directional delocalization of Cooper pairs can promote nematogen ordering, resulting in long-range nematic order. We obtain the transport properties of our model within an effective resistor network picture. We discuss these ideas in the context of the 2D electron gas at the (111) KTaO3 interface and the doped topological insulators NbxBi2Se3 and CuxBi2Se3. Our work makes contact with Phil Anderson’s numerous contributions to broken symmetries driven by the saving of kinetic energy, including double exchange ferromagnetism and the interlayer tunneling theory of high Tc superconductivity.

Multi-Operator Connectivity Sharing for Reliable Networks: A Data-Driven Risk Analysis

A key distinction between today’s and future networks is the appetite for reliable communication to support emerging critical-communication services. In this paper, we study multi-operator connectivity as a form of redundancy to support the design of reliable networks and investigate its trade-offs. This approach is motivated by 3GPP standardisation initiatives of dual-connectivity and similar techniques in industrial wired networks. We deploy a risk awareness performance metric to assess reliability: this superquantile metric accounts for periods of connectivity shortfalls. Our analysis shows that multi-operator connectivity brings significant reliability gains, in particular when network deployments by different operators exhibit high complementarity in coverage. We also explore the effects of multi-connectivity on spectral efficiency in times of high demand for bandwidth. Our study is based on a real-world dataset comprising signal strength indicators of three mobile operators in Dublin, Ireland.

Characteristic Study of Visible Light Communication and Influence of Coal Dust Particles in Underground Coal Mines

The critical environment of the underground mines is a risky zone for mining applications and it is very hazardous to engage the miners without a sophisticated communication system. The existing wired networks are susceptible to damage and the wireless radio systems experience severe fading that restricts the complete access to the entire assembly of a mine. Wireless optical communication is a better approach that can be incorporated in the erratic atmosphere of underground mines to overcome such issues, as lights are already used to illuminate the mine galleries. This study is focused on investigating the characteristics of visible light communication (VLC) in an underground coal mine. The entire scope of VLC is elaborated along with the influence of coal dust particles and the scattering model. The impact of coal dust clouds on visibility and attenuation is analyzed for visible light transmission. The shadowing effect generated by the pillars and mining machinery is estimated by employing the bimodal Gaussian distribution (BGD) approach in coal mines. The characteristic model of VLC for underground coal mines is presented by classifying the area of the mine into mine gallery and sub-galleries. The transmission links of VLC are categorized as the line of sight (LOS) link for direct propagation and the non-LOS (NLOS) link for reflected propagation. The scenarios of LOS and NLOS propagation are considered for each evaluating parameter. Furthermore, the performance of the proposed framework is examined by computing the received signal power, path loss, delay spread (DS), and signal to noise ratio (SNR).

Best strategy to control data on internet-of-robotic-things in heterogeneous networks

The control and transmission of huge data constitute an immense challenge in various types of networks (wired and wireless). Congestion caused by the high traffic and low throughput of huge data continues to be major problems in a heterogeneous platforms such as internet of things (IoT) technology and internet-of-robotic-things (IoRT). The heterogeneous network requires new models and mechanisms to deal with the increased challenges posed by IoT and IoRT. Accordingly, eliminating the issues that emerge has compelled finding improved solutions as a new strategy. This study proposed a new strategy called routing information and distance vector (RIDV) to create the best improvement of a heterogeneous network. The RIDV strategy activates the routing information protocol (RIPv2) on a router in wire network parallel with the ad-hoc on-demand distance vector (AODV) protocol on the wireless network. The RIDV strategy is used to solve the problems of the diversity of heterogeneous networks as the basis of the infrastructure IoRT technology. Hence, this strategy can reduce or avoid congestion through the use of enhanced and effective best routing protocols. Simulation results using OPNET show that the proposed method improved the quality of service (QoS) compared with other related strategies and AODV and RIPv1 protocols in terms of data drop, traffic drop, queue delay, and throughput.

IMPLEMENTATION OF CHORDAL RING NETWORK TOPOLOGY TO ENHANCE THE PERFORMANCE OF WIRELESS BROADBAND NETWORK

The expansion of networks involved higher jump on the users utilizing the networks resources, which may require extra higher bandwidth. Due to the development of technology especially those folded under the Internet of Things (IoT), the new demand of higher data rate is been witnesses among the users. In order to feed the demand of users with high data rate, broadband networks are required where high data rate can be ensured for each user. Broadband networks can be established using optical network that carries the data through wide broadband. Areas such as rural and forests sides which are witnessing plenty of natural obstacles such as mountains, trees, seas, etc. are forming big challenge for propagating a cable (wire) or optical network.
 Due to the limitations of the wire network, World Interoperability for Microwave Access (WiMAX) technology has been introduced as substitution for the broadband network. Such kind of alternative can be deployed through any geographical area without concerning on the wire paths. WiMAX preserved large coverage area and hence it may not suffer from the signal hand-off as in the case of another wireless network. In this project, Chordal Ring network topology is implemented to enhance the performance of wireless broadband network. With different routing protocols such as Destination Sequenced Distance Vector Protocol (DSDV) and Ad hoc On Demand Distance Vector (AODV), the network performance was examined for various Chordal Ring degree (e.g. fourth degree and fifth degree). Performance metrics such as number of transmitted packets, number of received packers, delivered packet rate (PDR), total number of drop packers (DP) and average queuing delay (been measured). Finally, the obtained results had been shown that fifth-degree Chordal Ring network is outperforming through DSDV routing protocol

Topological superconductivity in semiconductor–superconductor–magnetic-insulator heterostructures

Hybrid superconductor-semiconductor heterostructures are promising platforms for realizing topological superconductors and exploring Majorana bound states physics. Motivated by recent experimental progress, we theoretically study how magnetic insulators offer an alternative to the use of external magnetic fields for reaching the topological regime. We consider different setups, where: (1) the magnetic insulator induces an exchange field in the superconductor, which leads to a splitting in the semiconductor by proximity effect, and (2) the magnetic insulator acts as a spin-filter tunnel barrier between the superconductor and the semiconductor. We show that the spin splitting in the superconductor alone cannot induce a topological transition in the semiconductor. To overcome this limitation, we propose to use a spin-filter barrier that enhances the magnetic exchange and provides a mechanism for a topological phase transition. Moreover, the spin-dependent tunneling introduces a strong dependence on the band alignment, which can be crucial in quantum-confined systems. This mechanism opens up a route towards networks of topological wires with fewer constraints on device geometry compared to previous devices that require external magnetic fields.

Smart detection and prevention procedure for DoS attack in MANET

A self-organized wireless communication short-lived network containing collection of mobile nodes is mobile ad hoc network (MANET). The mobile nodes communicate with each other by wireless radio links without the use of any pre-established fixed communication network infrastructure or centralized administration, such as base stations or access points, and with no human intervention. In addition, this network has potential applications in conference, disaster relief, and battlefield scenario, and have received important attention in current years. There is some security concern that increases fear of attacks on the mobile ad-hoc network. The mobility of the NODE in a MANET poses many security problems and vulnerable to different types of security attacks than conventional wired and wireless networks. The causes of these issues are due to their open medium, dynamic network topology, absence of central administration, distributed cooperation, constrained capability, and lack of clear line of defense. Without proper security, mobile hosts are easily captured, compromised, and attacked by malicious nodes. Malicious nodes behavior may deliberately disrupt the network so that the whole network will be suffering from packet losses. One of the major concerns in mobile ad-hoc networks is a traffic DoS attack in which the traffic is choked by the malicious node which denied network services for the user. Mobile ad-hoc networks must have a safe path for transmission and correspondence which is a serious testing and indispensable issue. So as to provide secure communication and transmission, the scientist worked explicitly on the security issues in versatile impromptu organizations and many secure directing conventions and security measures within the networks were proposed. The goal of the work is to study DoS attacks and how it can be detected in the network. Existing methodologies for finding a malicious node that causes traffic jamming is based on node’s retains value. The proposed approach finds a malicious node using reliability value determined by the broadcast reliability packet (RL Packet). In this approach at the initial level, every node has zero reliability value, specific time slice, and transmission starts with a packet termed as reliability packet, node who responded properly in specific time, increases its reliability value and those nodes who do not respond in a specific time decreases their reliability value and if it goes to less than zero then announced that it’s a malicious node. Reliability approach makes service availability and retransmission time.

An SDN-based true end-to-end TCP for wireless LAN

Segment losses due to intermittent connectivity and mobility lead to sub optimal performance of the Transmission Control Protocol (TCP). This is due to the fact that segment loss is considered as a binary signal for triggering congestion control and retransmission mechanisms at the TCP sender. In wired networks, segments are dropped due to congestion at the routers and the strategy of taking missed acknowledgment as an implicit signal for congestion control performs well. However, in wireless networks, segment losses are primarily due to mobility and transmission errors. Unlike many previous efforts, this paper proposes the design and implementation of Software Defined Network (SDN) assisted TCP which does not require the wireless Access Points (APs) to be TCP-aware and preserves end to end semantics. Further, no changes are required to be done in TCP protocol implementation at the end-hosts. The proposed approach utilizes the programmability provided by the SDN paradigm to intelligently trigger the spurious timeout detection and response algorithms, already implemented in standard TCP. The proposed approach is compared with the standard TCP and SDN assisted Zero Window based approach on Linux kernels using virtual data-plane switches and APs provided by the Mininet-WiFi platform. The implementation results establish the applicability of the proposed approach.

Power-Lined: Electricity, Landscape, and the American Mind by Daniel L. Wuebben

Reviewed by: Power-Lined: Electricity, Landscape, and the American Mind by Daniel L. Wuebben Melissa Bollman Power-Lined: Electricity, Landscape, and the American Mind. By Daniel L. Wuebben. Lincoln: University of Nebraska Press, 2019. ix + 231 pp. Illustrations, map, notes, bibliography, index. $45.00, cloth. Focusing on the network of wires that connect energy, place, and culture in the United States, Daniel Wuebben's well-composed meditation on the vinelike web of overhead power lines offers a rich and compelling account of the ambiguities, tensions, and ironies associated with this often-overlooked piece of critical infrastructure. Power-Lined: Electricity, Landscape, and the American Mind is a welcome addition to the energy humanities and social sciences literature with its engaging exploration of the modern imaginaries that inspired the US transmission grid's design as well as the anxieties that accompanied the expansion of overhead lines across the Great Plains and beyond. Drawing on archival sources and personal memories of traversing the power-lined highways of Nebraska, this diverse collection of vignettes illustrates the electricity grid's distinctive imprint on US environments and psyches. As is the case for most large sociotechnical artefacts, the initial reactions to the now-ubiquitous power lines varied considerably among Native Americans and Anglo settlers—some celebrated their arrival as a harbinger of novel opportunities and prosperity, others regarded their presence as an intrusion, a threat to existing livelihoods and lifestyles, or instruments of colonization. While the stakes and terms of debates regarding overhead wires have changed since the early days of electrification, the technology's presence remains a subject of great controversy. Wuebben estimates that approximately one-third of Americans generally oppose the construction of new overground lines and are unlikely to be persuaded by arguments emphasizing the economic, environmental, or security benefits of a more robust grid. Although some have argued that expanding the public's technical knowledge about the grid could counteract some of the disdain for the wires' unsightliness, Wuebben suggests that cultivating a greater appreciation for the cultural, aesthetic, and place-making work performed by the electricity grid could also inspire the creation of more sustainable energyscapes. Though a more thorough discussion of how energy storage and other emerging technologies might impact future grid politics could have made for an even stronger analysis, Power-Lined: Electricity, Landscape, and the American Mind provides a captivating investigation into how energy infrastructure debates reflect contemporary social politics of in/visibility and an ambivalence toward modernity and technological progress in the US. This book should be of interest to anyone seeking to learn more about the relationship between electricity and the transformation of landscapes, both during this current period of energy transition and into the future. Melissa Bollman Graduate School of Geography Clark University Copyright © 2021 Center for Great Plains Studies, University of Nebraska-Lincoln

Hybrid DC-AC homes with roof top solar power

The paper investigates the feasibility of a hybrid DC-AC home with roof top solar power. In recent times, roof top solar power has become popular for residential homes. Generally, the power obtained from roof-top solar panels is converted to AC with a power control unit and routed to the existing wiring network of the houses designed essentially to support the Electric Utilities which deliver AC power. Solar power with DC bus routing power to various sub-units and Brushless DC (BLDC) motor-based systems have been successfully flown in satellites for decades. The study presents the possibility of having a dedicated DC bus (24V / 48V) in the home connected directly to roof-top solar panels along with the traditional wiring network to support AC power (220-230V) from Electric Utilities. The recent success of the BLDC based home appliances further highlights the potential. This will also help to benefit from higher efficiency due to BLDC and avoid the conversion losses as home appliances that can run on DC power are presently available. It is now possible to have an independent local Roof Top solar power-based DC home-grid to support lighting circuit and homeappliances that operate on DC power. The existing wiring network for AC can continue to support high power equipment like motors, boilers, washing machines etc., It will also simplify the power control unit as the traditional inverter portion is avoided. Thus, the proposed hybrid DC-AC home needs be viewed in terms of an overall green approach which will be a paradigm shift for energy efficiency and lower carbon footprint. It has the potential to boost the sale of DC home appliances.

Hybrid DC-AC homes with roof top solar power

The paper investigates the feasibility of a hybrid DC-AC home with roof top solar power. In recent times, roof top solar power has become popular for residential homes. Generally, the power obtained from roof-top solar panels is converted to AC with a power control unit and routed to the existing wiring network of the houses designed essentially to support the Electric Utilities which deliver AC power. Solar power with DC bus routing power to various sub-units and Brushless DC (BLDC) motor-based systems have been successfully flown in satellites for decades. The study presents the possibility of having a dedicated DC bus (24V / 48V) in the home connected directly to roof-top solar panels along with the traditional wiring network to support AC power (220-230V) from Electric Utilities. The recent success of the BLDC based home appliances further highlights the potential. This will also help to benefit from higher efficiency due to BLDC and avoid the conversion losses as home appliances that can run on DC power are presently available. It is now possible to have an independent local Roof Top solar power-based DC home-grid to support lighting circuit and home-appliances that operate on DC power. The existing wiring network for AC can continue to support high power equipment like motors, boilers, washing machines etc., It will also simplify the power control unit as the traditional inverter portion is avoided. Thus, the proposed hybrid DC-AC home needs be viewed in terms of an overall green approach which will be a paradigm shift for energy efficiency and lower carbon footprint. It has the potential to boost the sale of DC home appliances.

The Changing Dynamics of Wired and Wireless Networks

The Changing Dynamics of Wired and Wireless Networks

Interlaminar shear strength behaviour of surface treated steel wire mesh/glass fibre reinforced hybrid composite laminate

This research work deals with interlaminar shear behaviour of surface changed glass fiber/ treated steel wire mesh combined epoxy hybrid composites. The glass fiber is immersed with either by 1Normality concentrated sulfuric corrosive solution or sodium hydroxide. The hardened steel wire mesh is likewise surface treated by either electro polishing or sand blasting. The method used for fabrication of laminate is hand layup. The laminate comprising of corrosive treated glass fiber and electro polished or sand blasted tempered steel wire network displays prevalent interlaminar shear property in correlation with the composites made without any surface treatment. The mechanism and effect of surface treatment on glass fibre and steel wire mesh with respect to interlaminar shear behaviour is detailed with micro structure of the deformed region.

Wireless Control of Modular Multilevel Converter Submodules

Wireless control of modular multilevel converter (MMC) submodules offers several potential benefits to exploit, such as decreased converter costs and ease in converter installation. However, wireless control comes with several challenging engineering requirements. The control methods used with wired communication networks are not directly applicable to the wireless control due to the latency and reliability differences of wired and wireless networks. This article reviews the existing control architectures of MMCs and proposes a control and communication method for wireless submodule control. Also, a synchronization method for pulsewidth modulation carriers is proposed suitable for wireless control. The imperfections of wireless communication, such as higher latency and packet losses compared to wired communication, are analyzed for the operation of MMCs. The latency is fixed with a proper controller and wireless network design. The converter is rendered immune to the packet losses by decreasing the closed-loop control bandwidth. The functionality of the proposal is verified, for the first time, experimentally on a laboratory-scale MMC using a simple wireless network. It is shown that wireless control of MMC submodules with the proposed approach can perform comparably to the wired control.

Dirac Formulation for Universal Quantum Gates and Shor’s Integer Factorization in High-frequency Electric Circuits

Quantum computation may well be performed with the use of electric circuits. Especially, the Schr\"{o}dinger equation can be simulated by the lumped-element model of transmission lines, which is applicable to low-frequency electric circuits. In this paper, we show that the Dirac equation is simulated by the distributed-element model, which is applicable to high-frequency electric circuits. Then, a set of universal quantum gates (the Hadamard, phase-shift and CNOT gates) are constructed by networks made of transmission lines. We demonstrate Shor's prime factorization based on electric circuits. It will be possible to simulate any quantum algorithms simply by designing networks of metallic wires.

Single-Conductor Transmission Line Model Incorporating Radiation Reaction

Increasing attention has been paid to the study of electromagnetic (EM) phenomena in complicated wire networks [e.g., metamaterials and EM compatibility (EMC)]. However, their lack of physical insights usually prevents systematic analysis of the phenomena. To address this, this article describes a transmission line (TL) model of a finite-length single conductor without a return current path to be applied as a fundamental physical model. The model includes radiation effects in a self-consistent way (i.e., its radiation reaction is included in an explicit way), and it is based on Sommerfeld principal wave propagation (strictly speaking, its behavior is asymptotic as the wire's conductivity approaches infinity). This formulation naturally leads to the consequence that the current flowing along a single conductor illuminated by an incident EM field is classified into three components, which are dominated by physically distinct principles, the principal wave itself (I <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">tr</sub> , the traveling wave), the one reinduced by the traveling wave radiation (I <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">re</sub> , the radiation reaction), and the one that directly scatters the incident field (I <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">sc</sub> , the scattering wave). The EM energies of the traveling wave and radiation reaction components are stored in the TL and propagate, while the scattering component indicates an instantaneous scattering process. These components reveal the dynamical characteristics of a single-conductor TL model that includes radiation phenomena.