Critical Nodes Detection in IoT-Based Cyber-Physical Systems

The new generation of fast, small, and energy-efficient devices that can connect to the internet are already used for different purposes in healthcare, smart homes, smart cities, industrial automation, and entertainment. One of the main requirements in all kinds of cyber-physical systems is a reliable communication platform. In a wired or wireless network, losing some special nodes may disconnect the communication paths between other nodes. Generally, these nodes, which are called critical nodes, have many undesired effects on the network. The authors focus on three different problems. The first problem is finding the nodes whose removal minimizes the pairwise connectivity in the residual network. The second problem is finding the nodes whose removal maximizes the number of connected components. Finally, the third problem is finding the nodes whose removal minimizes the size of the largest connected component. All three problems are NP-Complete, and the authors provide a brief survey about the existing approximated algorithms for these problems.

Allosteric Determinants of the SARS-CoV-2 Spike Protein Binding with Nanobodies: Examining Mechanisms of Mutational Escape and Sensitivity of the Omicron Variant

Structural and biochemical studies have recently revealed a range of rationally engineered nanobodies with efficient neutralizing capacity against SARS-CoV-2 virus and resilience against mutational escape. In this study, we performed a comprehensive computational analysis of the SARS-CoV-2 spike trimer complexes with Nb6, VHH E and bi-paratopic VHH VE nanobodies. We combined atomistic dynamics and collective motions analysis with binding free energy scanning, perturbation-response scanning and network centrality analysis to examine mechanisms of nanobody-induced allosteric modulation and cooperativity in the SARS-CoV-2 spike trimer complexes with these nanobodies. By quantifying energetic and allosteric determinants of the SARS-CoV-2 spike protein binding with nanobodies, we also examined nanobody-induced modulation of escaping mutations and the effect of the Omicron variant on nanobody binding. The mutational scanning analysis supported the notion that E484A mutation can have a significant detrimental effect on nanobody binding and result in Omicron-induced escape from nanobody neutralization. Our findings showed that SARS-CoV-2 spike protein may exploit plasticity of specific allosteric hotspots to generate escape mutants that alter response to binding without compromising activity. The network analysis supported these findings showing that VHH VE nanobody binding can induce long-range couplings between the cryptic binding epitope and ACE2-binding site through a broader ensemble of communication paths that is less dependent on specific mediating centers and therefore may be less sensitive to mutational perturbations of functional residues. The results suggest that binding affinity and long-range communications of the SARS-CoV-2 complexes with nanobodies can be determined by structurally stable regulatory centers and conformationally adaptable hotspots that are allosterically coupled and collectively control resilience to mutational escape.

LIGHT IN THE INTERIORS OF THE URBAN LANDSCAPE

Urban compositions, which organize spaces in contemporary cities, are often perceived by its users – citizens, only as a net of communication paths There are known initiatives by more or less formalised social groups, which, in order to bring hitherto unnoticed fragments of urban territories into public consciousness, support their revitalisation, as well as the efforts of local authorities (also professional) related to architectural and urban education of children. These actions should facilitate the reading of the composition of urban spaces, which seems necessary for their proper use. This task is easier when the composition is clear, based on a conscious perception of existing spatial structures. Crystalline structures are best highlighted by light. It builds a scenography of space, helps in its perception and brings out formally important points. This article presents selected aspects of the use of daylight and artificial light in urban interiors.

A concept design stages protocol to support collaborative processes in architecture, engineering and construction projects

Purpose This paper proposes and tests, through a series of structured multi-disciplinary design activities, a “Concept Design Stages Protocol” (CDS Protocol) to structure project initiation, to attain smoother collaboration and greater consensus among multi-disciplinary project teams. Design/methodology/approach A collaborative approach from the outset is imperative for project success, especially when considering multi-disciplinary teams in the architecture, engineering and construction (AEC) industry. However, involving different disciplines hinders communication paths and affects informed decision-making. Findings Based on these findings, the research demonstrates that the CDS Protocol provides a solid foundation to aid in the optimal implementation of collaborative design, and with particular regard to multi-disciplinary working. Originality/value The research demonstrates the potential for significant improvement in the optimisation of the conceptual design stages, with positive implications for time, communication and whole-team engagement.

An improved AODV routing security algorithm based on blockchain technology in ad hoc network

Ad hoc network is a special network with centerless and dynamic topology. Due to the free mobility of the nodes, routing security has been a bottleneck problem that plagues its development. Therefore, a multi-path QoS (quality of service) routing security algorithm based on blockchain by improving the traditional AODV (ad hoc on-demand distance vector) protocol (AODV-MQS) is proposed. Firstly, a chain of nodes is established in the network and the states of all nodes by making the intermediate nodes on the chain are saved. Secondly, the smart contract in the blockchain is set to filter out the nodes that meet the QoS constraints. Finally, two largest unrelated communication paths are found in the blockchain network through smart contract, one of which is the main path and the other is the standby path. Simulation experiments show that the performance of the proposed algorithm is better than other algorithms, especially in an unsafe environment.

Victims as Stakeholders: Insights from the Intersection of Psychosocial, Ethical, and Crisis Communication Paths

This article examines the position of victims and those affected within communication theory. Current research has broadly been skewed toward reputation management and protecting brand value as primary goals of crisis communication efforts. As crises affect real people, crisis communication theory needs to be adapted to include their needs. To assure their needs are met, an integration of business ethics and psychosocial mechanisms in the field of crisis communication is proposed. This integration prevents crisis communication output from becoming an additional source of stress to the affected in the aftermath of crises. We offer recommendations for crisis communication scholarship to be inclusive and beneficial to victims and the affected in the aftermath of crises.

An Improved AODV Routing Security Algorithm Based on Blockchain Technology in Ad Hoc Network

Ad Hoc network is a special network with centerless and dynamic topology. Due to the free mobility of the nodes, routing security has been a bottleneck problem that plagues its development. Therefore, a multi-path QoS (Quality of Service) routing security algorithm based on blockchain by improving the traditional AODV (Ad hoc On-Demand Distance Vector) protocol (AODV-MQS) is proposed. Firstly, a chain of nodes is established in the network and the states of all nodes by making the intermediate nodes on the chain are saved. Secondly, the smart contract in the blockchain is set to filter out the nodes that meet the QoS constraints. Finally, two largest unrelated communication paths are found in the blockchain network through smart contract, one of which is the main path and the other is the standby path. Simulation experiments show that the performance of the proposed algorithm is better than other algorithms, especially in an unsafe environment.

An Analysis of Natural Factors Affecting the Dispersal and Establishment of Iron Age III Settlements in the Western Zayandehrand Basin (West and Northwest of Isfahan)

Humans are always lenders to their surroundings which makes it possible to create habitable environments and create habitat patterns that fit the surrounding environment. In this research, settlement patterns of Iron Age III sites in the west and northwest of Isfahan was studied via GIS. The area studied is one of the most important but unknown areas of archaeological research due to its location in the center of the Iranian plateau and a link between the north-west and the south-west of the country. The environmental characteristics of the studied area have attracted the attention of humans since ancient times. Therefore, it was considered necessary to conduct archaeological excavations. To achieve this goal, the area was first studied archaeologically. As a result of this survey, approximately 50 ancient sites were identified which included the statistical population used for analysis. The effect of environmental variables on the distribution of settlements in the study area was investigated including altitude, slope (percentage and direction), climate, geological structure, distances and proximity to water resources, distance to and land use, and the proximity to communication paths. Through analytical-descriptive method, the factors affecting the formation and distribution of the establishment patterns of the period in question was studied. After analyzing the information and maps, the results indicated that among all the factors, three environmental factors were the most important in the formation of ancient settlements of the Iron Age III era in the west and northwest of Isfahan: factors relating to water resources, proximity to communication paths, and slope percentage and direction.

An Improved AODV Routing Security Algorithm Based on Blockchain in Ad Hoc Network

Ad Hoc network is a special network with no center and dynamic topology changes. Due to the free mobility of nodes, routing security has always been a bottleneck problem that plagues network development. Therefore, this paper proposes a multi-path QoS (Quality of Service) routing security algorithm based on blockchain by improving the traditional AODV (Ad hoc On-Demand Distance Vector) protocol (AODV-MQS). The algorithm first establishes a blockchain network and saves the state of all nodes by making the intermediate nodes on the chain. Then the smart contract in the blockchain is set to filter out the nodes that meet the QoS constraints. Finally, two largest unrelated communication paths are found in the blockchain network through smart contract, one of which is the main path and the other is the standby path. Simulation experiments show that this algorithm has better performance than other algorithms in an unsafe environment.

The research on a Multipath Forwarding Strategy in Wireless Sensor Networks

Wireless communication signals are unstable, WSN network topology changes frequently, network dynamics are strong, and single path forwarding is difficult to provide high quality of service. A vector address-based end-to-end multi-path forwarding mechanism and path recovery algorithm are proposed. Although a single path cannot continuously guarantee network connection, multiple paths together can provide network connection with high reliability. In this method, the caller applies for and stores multiple relatively independent communication paths, and ranks them for use according to the path cost. The experimental results show that the performance of the above method is significantly improved.