Extra connectivity is an important indicator of the robustness of a multiprocessor system in presence of failing processors. The Formula Omitted-extra conditional diagnosability and the Formula ...Omitted-diagnosability are two important diagnostic strategies at system-level that can significantly enhance the syste's self-diagnosing capability. The Formula Omitted-extra conditional diagnosability is defined under the assumption that every component of the system removing a set of faulty vertices has more than Formula Omitted vertices. The Formula Omitted-diagnosis strategy can detect up to Formula Omitted faulty processors which might include at most Formula Omitted misdiagnosed processors, where Formula Omitted is typically a small integer number. In this paper, we analyze the combinatorial properties and fault tolerant ability for an Formula Omitted-arrangement graph, denoted by Formula Omitted, a well-known interconnection network proposed for multiprocessor systems. We first establish that the Formula Omitted's one-extra connectivity is Formula Omitted (Formula Omitted, Formula Omitted), two-extra connectivity is Formula Omitted (Formula Omitted, Formula Omitted), and three-extra connectivity is Formula Omitted (Formula Omitted, Formula Omitted or Formula Omitted, Formula Omitted), respectively. And then, we address the Formula Omitted-extra conditional diagnosability of Formula Omitted under the PMC model for Formula Omitted. Finally, we determine that the Formula Omitted-arrangement graph Formula Omitted is Formula Omitted-diagnosable (Formula Omitted, Formula Omitted), Formula Omitted-diagnosable (Formula Omitted, Formula Omitted), and Formula Omitted-diagnosable (Formula Omitted, Formula Omitted) under the PMC model, respectively.
Although the middle temporal gyrus (MTG) has been parcellated into subregions with distinguished anatomical connectivity patterns, whether the structural topography of MTG can inform functional ...segregations of this area remains largely unknown. Accumulating evidence suggests that the brain's underlying organization and function can be directly and effectively delineated with resting‐state functional connectivity (RSFC) by identifying putative functional boundaries between cortical areas. Here, RSFC profiles were used to explore functional segregations of the MTG and defined four subregions from anterior to posterior in two independent datasets, which showed a similar pattern with MTG parcellation scheme obtained using anatomical connectivity. The functional segregations of MTG were further supported by whole brain RSFC, coactivation, and specific RFSC, and coactivation mapping. Furthermore, the fingerprint with predefined 10 networks and functional characterizations of each subregion using meta‐analysis also identified functional distinction between subregions. The specific connectivity analysis and functional characterization indicated that the bilateral most anterior subregions mainly participated in social cognition and semantic processing; the ventral middle subregions were involved in social cognition in left hemisphere and auditory processing in right hemisphere; the bilateral ventro‐posterior subregions participated in action observation, whereas the left subregion was also involved in semantic processing; both of the dorsal subregions in superior temporal sulcus were involved in language, social cognition, and auditory processing. Taken together, our findings demonstrated MTG sharing similar structural and functional topographies and provide more detailed information about the functional organization of the MTG, which may facilitate future clinical and cognitive research on this area.
The temporal evolution of functional connectivity (FC) within the confines of individual scans is nowadays often explored with functional neuroimaging. This is particularly true for resting-state; ...yet, FC-dynamics have also been investigated as subjects engage on numerous tasks. It is these research efforts that constitute the core of this survey. First, empirical observations on how FC differs between task and rest—independent of temporal scale—are reviewed, as they underscore how, despite overall preservation of network topography, the brain's FC does reconfigure in systematic ways to accommodate task demands. Next, reports on the relationships between instantaneous FC and perception/performance in subsequent trials are discussed. Similarly, research where different aspects of task-concurrent FC-dynamics are explored or utilized to predict ongoing mental states are also examined. The manuscript finishes with an incomplete list of challenges that hopefully fuels future work in this vibrant area of neuroscientific research. Overall, this review concludes that task-concurrent FC-dynamics, when properly characterized, are relevant to behavior, and that their translational value holds considerable promise.
•Functional connectivity reshapes efficiently when switching between rest and task.•Moment-to-moment FC can predict subsequent perceptual outcomes.•Task-concurrent dynamic-FC metrics have significant behavioral relevance.•Analytical and interpretational challenges of task dynamic-FC are discussed.
This paper considers the tasks of supporting the connectivity of nodes in communication networks of unmanned transport (VANET/MANET-networks). High dynamics, decentralization and absence of hierarchy ...in the networks of this type actualize the task of supporting the connectivity of nodes with software-configurable security services, providing the network protection. It is offered to use a Blockchain technology based system for VANET/MANET network topologyand authentication data distribution and storage. The issue of unlimited blockchain growth preventing this method from being implemented in VANET/MANET networks is considered. The existing solutions of this issueare analyzed and drawbacks are identified. A notion of blockchain with floating genesis block is introduced and its advantages over similar ideas are demonstrated thus allowing it to be used to resolve the issue of continuously growing blockchain within the systems with stalingtransactions as a whole and in VANET/MANET networks in particular.
Species across the planet are shifting their ranges to track suitable climate conditions in response to climate change. Given that protected areas have higher quality habitat and often harbor higher ...levels of biodiversity compared to unprotected lands, it is often assumed that protected areas can serve as steppingstones for species undergoing climate‐induced range shifts. However, there are several factors that may impede successful range shifts among protected areas, including the distance that must be traveled, unfavorable human land uses and climate conditions along potential movement routes, and lack of analogous climates. Through a species‐agnostic lens, we evaluate these factors across the global terrestrial protected area network as measures of climate connectivity, which is defined as the ability of a landscape to facilitate or impede climate‐induced movement. We found that over half of protected land area and two‐thirds of the number of protected units across the globe are at risk of climate connectivity failure, casting doubt on whether many species can successfully undergo climate‐induced range shifts among protected areas. Consequently, protected areas are unlikely to serve as steppingstones for a large number of species under a warming climate. As species disappear from protected areas without commensurate immigration of species suited to the emerging climate (due to climate connectivity failure), many protected areas may be left with a depauperate suite of species under climate change. Our findings are highly relevant given recent pledges to conserve 30% of the planet by 2030 (30 × 30), underscore the need for innovative land management strategies that allow for species range shifts, and suggest that assisted colonization may be necessary to promote species that are adapted to the emerging climate.
There are several factors that may impede successful climate‐induced range shifts among protected areas, including the distance that must be traveled, unfavorable human land uses and climate conditions along potential movement routes, and lack of analogous climates. We found that over half of protected land area and two‐thirds of the number of protected units across the globe are at risk of climate connectivity failure, casting doubt on whether many species can successfully undergo climate‐induced range shifts among protected areas. Consequently, protected areas are unlikely to serve as steppingstones for a large number of species under a warming climate.
We review the theory and algorithms of electrophysiological brain connectivity analysis. This tutorial is aimed at providing an introduction to brain functional connectivity from electrophysiological ...signals, including electroencephalography, magnetoencephalography, electrocorticography, and stereoelectroencephalography. Various connectivity estimators are discussed, and algorithms introduced. Important issues for estimating and mapping brain functional connectivity with electrophysiology are discussed.
Spatio-temporal connectivity patterns of a wetland as a function of the land use/land cover (LULC) of its catchment have been analysed in a GIS environment. An innovative method has been implemented ...for mapping ‘dynamic hydrological connectivity’ for a water-stressed wetland of Kosi-Ganga interfluve area in the middle Ganga Plains, India for pre- and post-monsoon seasons over a time-span of 29 years (1989 to 2017). It was accomplished by using the time-series NDVI (Normalized Difference Vegetation Index) data and the connectivity response unit (CRU) approach by applying geostatistical methods namely the Getis-Ord Gi* and Mann-Kendall trend test statistics. The study area is principally a rain-fed wetland located in flat terrain (average slope of ~2°) under intensive agriculture and receives water as overland flows. The agriculture dominated LULC in this region is controlling the wetland-catchment connectivity scenarios and the overall connectivity potential of the catchment is higher in the pre-monsoon compared to the post-monsoon season. High and low connectivity potentials of different areas of the catchment with respect to the wetland have been classified into three types: persistent, intensifying, and diminishing. The areas with ‘persistent’ high or low connectivity potentials have been attributed to the topographic factors which are static in nature, such as the proximity to the wetland and the presence of other geomorphic features. The ‘intensifying’ and ‘diminishing’ clusters have been linked to changing LULC patterns. The proposed method holds significant implications for the restoration of wetland-catchment connectivity and can be applied in any flatland terrain where hydrological connectivity is strongly influenced by the surface impedance induced by LULC.
Display omitted
•Dynamic connectivity patterns of a wetland as a function of the land use/land cover•Concept of Connectivity Response Units' (CRUs) coupled with space-time cubes•Wetland-catchment connectivity higher for pre-monsoon compared to post-monsoon•‘Persistent’ clusters act like ‘buffers’ and ‘barriers’.•‘Intensifying’ and ‘diminishing’ clusters result from changing LULC patterns.
Let G be a graph with vertex set V(G) and S⊆V(G). An S-path of G is a path which connects all vertices of S in G. Let P1 and P2 be S-paths. If E(P1)∩E(P2)=0̸ and V(P1)∩V(P2)=S, then the two paths P1 ...and P2 are called internally disjointS-paths. Denoted by πG(S) the maximum number of any pairwise internally disjoint S-paths in G. The r-path-connectivityπr(G) is defined as πr(G)= min{πG(S)|S⊆V(G),|S|=r}, where 2≤r≤|V(G)|. In this paper, we focus on the 3-path-connectivity of the n-dimensional star graph Sn and obtain that π3(Sn)=3(n−1)−14 with n≥3.
Determining the connectivity of fluids in hydrocarbon reservoirs is a key challenge during the appraisal stage. Such information is critical for assessing the economic viability and planning ...reservoir development. Although several tools exist to determine static connectivity and the fluid column organisation post-hydrocarbon emplacement, it is extremely difficult to determine the extent of the connectivity between fluids of different phases. Conventional connectivity studies on the Tormore field, West of Shetland Basin, UK have resolved the vertical connectivity of one well (T2) but have been unable to resolve further vertical or lateral connectivity. Here, we outline a new tool for assessing hydrocarbon connectivity by completing the first intra-field connectivity study of the noble gas composition (He, Ne, Ar, Kr and Xe) of fluids from individual reservoir units, allowing the resolution of both the vertical and lateral connectivity within the Tormore field. To achieve this, we obtain fluid samples from archived PVT vessels rather than from the wellhead or platform separators, allowing sampling of the individual reservoir units encountered during drilling. Our findings corroborate previous connectivity studies undertaken on the oil well, T2, confirming that the reservoir unit of T2-A is isolated from the lower reservoir units. We apply the same method to the gas well, T3, finding that unit T3-A is isolated from the lower reservoir units. In addition, we identify a previously unknown connection between the gas and oil phase that is separated by a poorly constrained fault. These findings confirm the effectiveness of using noble gas fingerprints to assess the connectivity of fluids in different phases, providing a new tool for understanding connectivity in hydrocarbon and non-hydrocarbon settings (e.g. Carbon, Capture and Storage).
•Outlines a new methodology to obtain fluid samples for noble gas analysis from PVT cells•Provides the first intra-field noble gas study using samples collected directly from individual reservoir units•Demonstrates the application of noble gases for resolving reservoir connectivity•Resolved the lateral connectivity of two fluid phases separated by fault
We study the Laplacian eigenvalues of the zero divisor graph Γ(Zn) of the ring Zn and prove that Γ(Zpt) is Laplacian integral for every prime p and positive integer t≥2. We also prove that the ...Laplacian spectral radius and the algebraic connectivity of Γ(Zn) for most of the values of n are, respectively, the largest and the second smallest eigenvalues of the vertex weighted Laplacian matrix of a graph which is defined on the set of proper divisors of n. The values of n for which algebraic connectivity and vertex connectivity of Γ(Zn) coincide are also characterized.
PDF
