A Multi-resolution Community Partition Method based on Node Degree

: Mobile ad hoc networks (MANET) hold a set of numerous mobile computing devices useful for communication with one another with no centralized control. Due to the inherent features of MANET such as dynamic topology, constrained on bandwidth, energy and computing resources, there is a need to design the routing protocols efficiently. Flooding is a directive for managing traffic since it makes use of only chosen nodes for transmitting data from one node to another. This paper intends to develop a new Cluster-Based Flooding using Fuzzy Logic Scheme (CBF2S). To construct clusters and choose proper cluster heads (CHs), thefuzzy logic approach is applied with the use of three parameters namely link quality, node mobility and node degree. The presented model considerably minimizes the number of retransmissions in the network. The presented model instructs the cluster members (CM) floods the packets inside a cluster called intra-cluster flooding and CHs floods the packets among the clusters called inter-cluster flooding. In addition, the gateway sends a packet to another gateway for minimizing unwanted data retransmissions when it comes under different CH. The presented CBF2S is simulated using NS2 tool under the presence of varying hop count. The CBF2S model exhibits maximum results over the other methods interms of overhead, communication overhead, traffic load, packet delivery ratio and the end to end delay.

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Improved biorefinery pathways of marine diatoms using a water miscible ionic liquid and its colloidal solution: efficient lipid extraction and in situ synthesis of fluorescent carbon dots for bio-imaging applications

RSC Advances ◽

10.1039/d1ra01425k ◽

2021 ◽

Vol 11 (35) ◽

pp. 21207-21215

Author(s):

Paidi Murali Krishna ◽

Veerababu Polisetti ◽

Krishnaiah Damarla ◽

Subir Kumar Mandal ◽

Arvind Kumar

Keyword(s):

Ionic Liquid ◽

Colloidal Solution ◽

Polar Solvent ◽

Lipid Extraction ◽

In Situ Synthesis ◽

Marine Diatoms ◽

Bio Imaging ◽

Partition Method ◽

Fluorescent Carbon Dots

In this study, a water-miscible ionic liquid (IL), 1-ethyl-3-methylimidazoliumacetate ([EMIM][Ac]), has been used for lipid extraction from marine diatoms Thalassiosira lundiana CSIR-CSMCRI 001 by following a non-polar solvent partition method.

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The unbalanced reorganization of weaker functional connections induces the altered brain network topology in schizophrenia

Scientific Reports ◽

10.1038/s41598-021-94825-x ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Rossana Mastrandrea ◽

Fabrizio Piras ◽

Andrea Gabrielli ◽

Nerisa Banaj ◽

Guido Caldarelli ◽

...

Keyword(s):

Resting State ◽

Functional Organization ◽

Functional Integration ◽

Brain Network ◽

Modular Organization ◽

Node Degree ◽

Imaging Data ◽

Brain Disorder ◽

Functional Connections ◽

The Brain

AbstractNetwork neuroscience shed some light on the functional and structural modifications occurring to the brain associated with the phenomenology of schizophrenia. In particular, resting-state functional networks have helped our understanding of the illness by highlighting the global and local alterations within the cerebral organization. We investigated the robustness of the brain functional architecture in 44 medicated schizophrenic patients and 40 healthy comparators through an advanced network analysis of resting-state functional magnetic resonance imaging data. The networks in patients showed more resistance to disconnection than in healthy controls, with an evident discrepancy between the two groups in the node degree distribution computed along a percolation process. Despite a substantial similarity of the basal functional organization between the two groups, the expected hierarchy of healthy brains' modular organization is crumbled in schizophrenia, showing a peculiar arrangement of the functional connections, characterized by several topologically equivalent backbones. Thus, the manifold nature of the functional organization’s basal scheme, together with its altered hierarchical modularity, may be crucial in the pathogenesis of schizophrenia. This result fits the disconnection hypothesis that describes schizophrenia as a brain disorder characterized by an abnormal functional integration among brain regions.

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Measuring Dynamic Changes in the Spatial Pattern and Connectivity of Surface Waters Based on Landscape and Graph Metrics: A Case Study of Henan Province in Central China

Land ◽

10.3390/land10050471 ◽

2021 ◽

Vol 10 (5) ◽

pp. 471

Author(s):

Bo Mu ◽

Guohang Tian ◽

Gengyu Xin ◽

Miao Hu ◽

Panpan Yang ◽

...

Keyword(s):

Surface Water ◽

Nearest Neighbor ◽

Dynamic Change ◽

Henan Province ◽

Central China ◽

Node Degree ◽

Human Society ◽

Stepping Stones ◽

Dynamic Changes ◽

Graph Metrics

An understanding of the scientific layout of surface water space is crucial for the sustainable development of human society and the ecological environment. The objective of this study was to use land-use/land-cover data to identify the spatiotemporal dynamic change processes and the influencing factors over the past three decades in Henan Province, central China. Multidisciplinary theories (landscape ecology and graph theory) and methods (GIS spatial analysis and SPSS correlation analysis) were used to quantify the dynamic changes in surface water pattern and connectivity. Our results revealed that the water area decreased significantly during the periods of 1990–2000 and 2010–2018 due to a decrease in tidal flats and linear waters, but increased significantly in 2000–2010 due to an increase in patchy waters. Human construction activities, socioeconomic development and topography were the key factors driving the dynamics of water pattern and connectivity. The use of graph metrics (node degree, betweenness centrality, and delta probability of connectivity) in combination with landscape metrics (Euclidean nearest-neighbor distance) can help establish the parameters of threshold distance between connected habitats, identify hubs and stepping stones, and determine the relatively important water patches that require priority protection or development.

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A Community-Structure-Based Method for Estimating the Fractal Dimension, and its Application to Water Networks for the Assessment of Vulnerability to Disasters

Water Resources Management ◽

10.1007/s11269-021-02773-y ◽

2021 ◽

Vol 35 (4) ◽

pp. 1197-1210

Author(s):

C. Giudicianni ◽

A. Di Nardo ◽

R. Greco ◽

A. Scala

Keyword(s):

Fractal Dimension ◽

Community Structure ◽

Distribution Systems ◽

Water Distribution ◽

Scaling Law ◽

Vulnerability Index ◽

The Self ◽

Node Degree ◽

Specific Response ◽

Self Similarity

AbstractMost real-world networks, from the World-Wide-Web to biological systems, are known to have common structural properties. A remarkable point is fractality, which suggests the self-similarity across scales of the network structure of these complex systems. Managing the computational complexity for detecting the self-similarity of big-sized systems represents a crucial problem. In this paper, a novel algorithm for revealing the fractality, that exploits the community structure principle, is proposed and then applied to several water distribution systems (WDSs) of different size, unveiling a self-similar feature of their layouts. A scaling-law relationship, linking the number of clusters necessary for covering the network and their average size is defined, the exponent of which represents the fractal dimension. The self-similarity is then investigated as a proxy of recurrent and specific response to multiple random pipe failures – like during natural disasters – pointing out a specific global vulnerability for each WDS. A novel vulnerability index, called Cut-Vulnerability is introduced as the ratio between the fractal dimension and the average node degree, and its relationships with the number of randomly removed pipes necessary to disconnect the network and with some topological metrics are investigated. The analysis shows the effectiveness of the novel index in describing the global vulnerability of WDSs.

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