scholarly journals Beyond two-point statistics: using the minimum spanning tree as a tool for cosmology

2019 ◽  
Vol 491 (2) ◽  
pp. 1709-1726 ◽  
Author(s):  
Krishna Naidoo ◽  
Lorne Whiteway ◽  
Elena Massara ◽  
Davide Gualdi ◽  
Ofer Lahav ◽  
...  
Keyword(s):  
Spanning Tree ◽  
Large Scale ◽  
Minimum Spanning Tree ◽  
Cosmological Parameters ◽  
Skeletal Structure ◽  
Additional Information ◽  
The Rich ◽  
Unique Graph ◽  
The Individual ◽  
First Time

ABSTRACT Cosmological studies of large-scale structure have relied on two-point statistics, not fully exploiting the rich structure of the cosmic web. In this paper we show how to capture some of this cosmic web information by using the minimum spanning tree (MST), for the first time using it to estimate cosmological parameters in simulations. Discrete tracers of dark matter such as galaxies, N-body particles or haloes are used as nodes to construct a unique graph, the MST, that traces skeletal structure. We study the dependence of the MST on cosmological parameters using haloes from a suite of COmoving Lagrangian Acceleration (COLA) simulations with a box size of $250\ h^{-1}\, {\rm Mpc}$, varying the amplitude of scalar fluctuations (As), matter density (Ωm), and neutrino mass (∑mν). The power spectrum P and bispectrum B are measured for wavenumbers between 0.125 and 0.5 $h\, {\rm Mpc}^{-1}$, while a corresponding lower cut of ∼12.6 $h^{-1}\, {\rm Mpc}$ is applied to the MST. The constraints from the individual methods are fairly similar but when combined we see improved 1σ constraints of $\sim 17{{\ \rm per\ cent}}$ ($\sim 12{{\ \rm per\ cent}}$) on Ωm and $\sim 12{{\ \rm per\ cent}}$ ($\sim 10{{\ \rm per\ cent}}$) on As with respect to P (P + B) thus showing the MST is providing additional information. The MST can be applied to current and future spectroscopic surveys (BOSS, DESI, Euclid, PSF, WFIRST, and 4MOST) in 3D and photometric surveys (DES and LSST) in tomographic shells to constrain parameters and/or test systematics.

scholarly journals The neuronal basis for consciousness

1998 ◽  
Vol 353 (1377) ◽  
pp. 1841-1849 ◽  
Author(s):  
◽  
R. Llinás ◽  
U. Ribary ◽  
D. Contreras ◽  
C. Pedroarena
Keyword(s):  
Large Scale ◽  
Basic Assumption ◽  
Human Cognition ◽  
Neuronal Organization ◽  
Global Function ◽  
Loop Function ◽  
Functional States ◽  
The Rich ◽  
First Time ◽  
The Brain

Attempting to understand how the brain, as a whole, might be organized seems, for the first time, to be a serious topic of inquiry. One aspect of its neuronal organization that seems particularly central to global function is the rich thalamocortical interconnectivity, and most particularly the reciprocal nature of the thalamocortical neuronal loop function. Moreover, the interaction between the specific and non-specific thalamic loops suggests that rather than a gate into the brain, the thalamus represents a hub from which any site in the cortex can communicate with any other such site or sites. The goal of this paper is to explore the basic assumption that large–scale, temporal coincidence of specific and non–specific thalamic activity generates the functional states that characterize human cognition.

Research on Routing Protocol for Large-Scale Wireless Sensor Networks

2014 ◽  
Vol 511-512 ◽  
pp. 146-149
Author(s):  
Kai Zhang ◽  
Min Jin
Keyword(s):  
Wireless Sensor Networks ◽  
Routing Protocol ◽  
Spanning Tree ◽  
Large Scale ◽  
Minimum Spanning Tree ◽  
Cluster Head ◽  
Wireless Sensor ◽  
Cluster Heads ◽  
Application Characteristics ◽  
The One

Aimed at the application characteristics of the large-scale WSN, a new clustering routing protocol LEACH_CHMST is proposed in this paper. The multi-hop strategy for cluster-heads communication has been introduced instead of the one-hop strategy in LEACH, and a minimum spanning tree of cluster-head is established, in which the routes from all cluster-heads to sink are found.

scholarly journals The Generalized STAR Modelling with Minimum Spanning Tree Approach of Weight Matrix for COVID-19 Case in Java Island

2021 ◽  
Vol 2084 (1) ◽  
pp. 012003
Author(s):  
Utriweni Mukhaiyar ◽  
Bayu Imadul Bilad ◽  
Udjianna Sekteria Pasaribu
Keyword(s):  
Spanning Tree ◽  
Large Scale ◽  
Minimum Spanning Tree ◽  
Weight Matrix ◽  
Average Score ◽  
New Approach ◽  
Central Java ◽  
Good Ability ◽  
The Relationship ◽  
Inverse Distance

Abstract The ongoing global Coronavirus 2019 (COVID-19) pandemic poses a major threat. The spread of the COVID-19 virus is likely to occur from one location to another location due to the mobility of people. Many efforts and policies have been made by each country to reduce the spread of the COVID-19 outbreak. The imposition of lockdown and large-scale social restrictions or social distancing has been widely applied to limit the transmission of this virus among the community and provincial levels. Both policies have proven effective in reducing the spread of the COVID-19 virus. To obtain the overview of this case, many researchers were conducted. Here, the Generalized STAR (GSTAR) model was applied to model the increasing number of COVID-19 positive cases per day in six provinces in Java Island. The data was recorded simultaneously in six locations, namely in the Provinces of Banten, Jakarta, West Java, Central Java, Yogyakarta Special Region, and East Java. This paper proposes a new approach in constructing the weight matrix required to build the GSTAR model, namely Minimum Spanning Tree (MST). The weight matrix represents the relationship among observed locations. By using the MST, a topological (undirected graph) network model could be created to show the correlation, centrality, and relationship on the increase of COVID-19 positive cases among the provinces in Java Island. The GSTAR(1;1) with the inverse distance weight matrix using MST presents a good ability to predict the COVID-19 increasing cases of Java island. This is indicated by the final MAPE average score of 19.55.

scholarly journals RANDOMIZATION YIELDS SIMPLE O(n log⋆ n) ALGORITHMS FOR DIFFICULT Ω(n) PROBLEMS

1992 ◽  
Vol 02 (01) ◽  
pp. 97-111 ◽  
Author(s):  
OLIVIER DEVILLERS
Keyword(s):  
Delaunay Triangulation ◽  
Spanning Tree ◽  
Minimum Spanning Tree ◽  
Simple Polygon ◽  
Complexity Of Algorithms ◽  
Additional Information ◽  
Influence Graph

We use here the results on the influence graph1 to adapt them for particular cases where additional information is available. In some cases, it is possible to improve the expected randomized complexity of algorithms from O(n log n) to O(n log ⋆ n). This technique applies in the following applications: triangulation of a simple polygon, skeleton of a simple polygon, Delaunay triangulation of points knowing the EMST (euclidean minimum spanning tree).

scholarly journals Large-scale star formation in Auriga region

2019 ◽  
Vol 492 (2) ◽  
pp. 2446-2467 ◽  
Author(s):  
A K Pandey ◽  
Saurabh Sharma ◽  
N Kobayashi ◽  
Y Sarugaku ◽  
K Ogura
Keyword(s):  
Star Formation ◽  
Spanning Tree ◽  
Large Scale ◽  
Minimum Spanning Tree ◽  
Young Stellar Objects ◽  
Molecular Gas ◽  
Archival Data ◽  
Stellar Objects ◽  
Tree Analysis ◽  
Formation Efficiency

ABSTRACT New observations in the VI bands along with archival data from the 2MASS and WISE surveys have been used to generate a catalogue of young stellar objects (YSOs) covering an area of about 6° × 6° in the Auriga region centred at l ∼ 173° and b ∼ 1.5°. The nature of the identified YSOs and their spatial distribution are used to study the star formation in the region. The distribution of YSOs along with that of the ionized and molecular gas reveals two ring-like structures stretching over an area of a few degrees each in extent. We name these structures as Auriga Bubbles 1 and 2. The centre of the Bubbles appears to be above the Galactic mid-plane. The majority of Class I YSOs are associated with the Bubbles, whereas the relatively older population, i.e. Class ii objects are rather randomly distributed. Using the minimum spanning tree analysis, we found 26 probable subclusters having five or more members. The subclusters are between ∼0.5 and ∼3 pc in size and are somewhat elongated. The star formation efficiency in most of the subcluster region varies between 5 ${{\ \rm per\ cent}}$ and 20 ${{\ \rm per\ cent}}$ indicating that the subclusters could be bound regions. The radii of these subclusters also support it.

scholarly journals Parallel Regional Segmentation Method of High-Resolution Remote Sensing Image Based on Minimum Spanning Tree

2020 ◽  
Vol 12 (5) ◽  
pp. 783 ◽  
Author(s):  
Wenjie Lin ◽  
Yu Li
Keyword(s):  
Remote Sensing ◽  
Parallel Processing ◽  
High Resolution ◽  
Spanning Tree ◽  
Large Scale ◽  
Minimum Spanning Tree ◽  
Process Efficiency ◽  
Qualitative Assessment ◽  
Segmentation Method ◽  
High Resolution Images

With finer spatial scale, high-resolution images provide complex, spatial, and massive information on the earth’s surface, which brings new challenges to remote sensing segmentation methods. In view of these challenges, finding a more effective segmentation model and parallel processing method is crucial to improve the segmentation accuracy and process efficiency of large-scale high-resolution images. To this end, this study proposed a minimum spanning tree (MST) model integrated into a regional-based parallel segmentation method. First, an image was decomposed into several blocks by regular tessellation. The corresponding homogeneous regions were obtained using the minimum heterogeneity rule (MHR) partitioning technique in a multicore parallel processing mode, and the initial segmentation results were obtained by the parallel block merging method. On this basis, a regionalized fuzzy c-means (FCM) method based on master-slave parallel mode was proposed to achieve fast and optimal segmentation. The proposed segmentation approach was tested on high-resolution images. The results from the qualitative assessment, quantitative evaluation, and parallel analysis verified the feasibility and validity of the proposed method.

Scheming

2018 ◽  
Author(s):  
Seán Damer
Keyword(s):  
Social Class ◽  
Housing Policy ◽  
Large Scale ◽  
Class Structure ◽  
Local Council ◽  
Housing Scheme ◽  
Post War ◽  
First Time ◽  
The Voice ◽  
House Building

This book seeks to explain how the Corporation of Glasgow, in its large-scale council house-building programme in the inter- and post-war years, came to reproduce a hierarchical Victorian class structure. The three tiers of housing scheme which it constructed – Ordinary, Intermediate, and Slum-Clearance – effectively signified First, Second and Third Class. This came about because the Corporation uncritically reproduced the offensive and patriarchal attitudes of the Victorian bourgeoisie towards the working-class. The book shows how this worked out on the ground in Glasgow, and describes the attitudes of both authoritarian housing officials, and council tenants. This is the first time the voice of Glasgow’s council tenants has been heard. The conclusion is that local council housing policy was driven by unapologetic considerations of social class.

Victorian Pain

2017 ◽  
Author(s):  
Rachel Ablow
Keyword(s):  
Nineteenth Century ◽  
Victorian Literature ◽  
Social Life ◽  
Charles Darwin ◽  
Harriet Martineau ◽  
The Status ◽  
History Of ◽  
The Individual ◽  
Natural Philosophers ◽  
First Time

The nineteenth century introduced developments in science and medicine that made the eradication of pain conceivable for the first time. This new understanding of pain brought with it a complex set of moral and philosophical dilemmas. If pain serves no obvious purpose, how do we reconcile its existence with a well-ordered universe? Examining how writers of the day engaged with such questions, this book offers a compelling new literary and philosophical history of modern pain. The book provides close readings of novelists Charlotte Brontë and Thomas Hardy and political and natural philosophers John Stuart Mill, Harriet Martineau, and Charles Darwin, as well as a variety of medical, scientific, and popular writers of the Victorian age. The book explores how discussions of pain served as investigations into the status of persons and the nature and parameters of social life. No longer conceivable as divine trial or punishment, pain in the nineteenth century came to seem instead like a historical accident suggesting little or nothing about the individual who suffers. A landmark study of Victorian literature and the history of pain, the book shows how these writers came to see pain as a social as well as a personal problem. Rather than simply self-evident to the sufferer and unknowable to anyone else, pain was also understood to be produced between persons—and even, perhaps, by the fictions they read.

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