scholarly journals Subgraph-Indexed Sequential Subdivision for Continuous Subgraph Matching on Dynamic Knowledge Graph

Complexity ◽  
2020 ◽  
Vol 2020 ◽  
pp. 1-18
Author(s):  
Yunhao Sun ◽  
Guanyu Li ◽  
Mengmeng Guan ◽  
Bo Ning
Keyword(s):  
Empirical Studies ◽  
Search Space ◽  
Knowledge Graph ◽  
Dynamic Graph ◽  
Matching Problem ◽  
Flow Graph ◽  
Query Graph ◽  
Subgraph Matching ◽  
Wide Range ◽  
Multiple Edges

Continuous subgraph matching problem on dynamic graph has become a popular research topic in the field of graph analysis, which has a wide range of applications including information retrieval and community detection. Specifically, given a query graph q , an initial graph G 0 , and a graph update stream △ G i , the problem of continuous subgraph matching is to sequentially conduct all possible isomorphic subgraphs covering △ G i of q on G i (= G 0   ⊕   △ G i ). Since knowledge graph is a directed labeled multigraph having multiple edges between a pair of vertices, it brings new challenges for the problem focusing on dynamic knowledge graph. One challenge is that the multigraph characteristic of knowledge graph intensifies the complexity of candidate calculation, which is the combination of complex topological and attributed structures. Another challenge is that the isomorphic subgraphs covering a given region are conducted on a huge search space of seed candidates, which causes a lot of time consumption for searching the unpromising candidates. To address these challenges, a method of subgraph-indexed sequential subdivision is proposed to accelerating the continuous subgraph matching on dynamic knowledge graph. Firstly, a flow graph index is proposed to arrange the search space of seed candidates in topological knowledge graph and an adjacent index is designed to accelerate the identification of candidate activation states in attributed knowledge graph. Secondly, the sequential subdivision of flow graph index and the transition state model are employed to incrementally conduct subgraph matching and maintain the regional influence of changed candidates, respectively. Finally, extensive empirical studies on real and synthetic graphs demonstrate that our techniques outperform the state-of-the-art algorithms.

scholarly journals Symmetric continuous subgraph matching with bidirectional dynamic programming

2021 ◽  
Vol 14 (8) ◽  
pp. 1298-1310
Author(s):  
Seunghwan Min ◽  
Sung Gwan Park ◽  
Kunsoo Park ◽  
Dora Giammarresi ◽  
Giuseppe F. Italiano ◽  
...  
Keyword(s):  
Dynamic Programming ◽  
Cyber Security ◽  
Spanning Tree ◽  
State Of The Art ◽  
The State ◽  
Dynamic Graph ◽  
Matching Problem ◽  
Edge Deletion ◽  
Query Graph ◽  
Subgraph Matching

In many real datasets such as social media streams and cyber data sources, graphs change over time through a graph update stream of edge insertions and deletions. Detecting critical patterns in such dynamic graphs plays an important role in various application domains such as fraud detection, cyber security, and recommendation systems for social networks. Given a dynamic data graph and a query graph, the continuous subgraph matching problem is to find all positive matches for each edge insertion and all negative matches for each edge deletion. The state-of-the-art algorithm TurboFlux uses a spanning tree of a query graph for filtering. However, using the spanning tree may have a low pruning power because it does not take into account all edges of the query graph. In this paper, we present a symmetric and much faster algorithm SymBi which maintains an auxiliary data structure based on a directed acyclic graph instead of a spanning tree, which maintains the intermediate results of bidirectional dynamic programming between the query graph and the dynamic graph. Extensive experiments with real and synthetic datasets show that SymBi outperforms the state-of-the-art algorithm by up to three orders of magnitude in terms of the elapsed time.

scholarly journals Optimized Distributed Subgraph Matching Algorithm Based on Partition Replication

Electronics ◽  
2020 ◽  
Vol 9 (1) ◽  
pp. 184
Author(s):  
Ling Yuan ◽  
Jiali Bin ◽  
Peng Pan
Keyword(s):  
Large Scale ◽  
High Efficiency ◽  
Search Space ◽  
Dynamic Graph ◽  
Matching Algorithm ◽  
Query Graph ◽  
Subgraph Matching ◽  
Match Algorithm ◽  
Large Scale Data ◽  
Scale Data

At present, with the explosive growth of data scale, subgraph matching for massive graph data is difficult to satisfy with efficiency. Meanwhile, the graph index used in existing subgraph matching algorithm is difficult to update and maintain when facing dynamic graphs. We propose a distributed subgraph matching algorithm based on Partition Replica (noted as PR-Match) to process the partition and storage of large-scale data graphs. The PR-Match algorithm first splits the query graph into sub-queries, then assigns the sub-query to each node for sub-graph matching, and finally merges the matching results. In the PR-Match algorithm, we propose a heuristic rule based on prediction cost to select the optimal merging plan, which greatly reduces the cost of merging. In order to accelerate the matching speed of the sub-query graph, a vertex code based on the vertex neighbor label signature is proposed, which greatly reduces the search space for the subquery. As the vertex code is based on the increment, the problem that the feature-based graph index is difficult to maintain in the face of the dynamic graph is solved. An abundance of experiments on real and synthetic datasets demonstrate the high efficiency and strong scalability of the PR-Match algorithm when handling large-scale data graphs.

scholarly journals A developmentally descriptive method for quantifying shape in gastropod shells

2020 ◽  
Vol 17 (163) ◽  
pp. 20190721
Author(s):  
J. Larsson ◽  
A. M. Westram ◽  
S. Bengmark ◽  
T. Lundh ◽  
R. K. Butlin
Keyword(s):  
Empirical Studies ◽  
Three Dimensional ◽  
Shell Shape ◽  
Large Set ◽  
Littorina Saxatilis ◽  
Shape Variation ◽  
Gastropod Shell ◽  
Geometric Morphometric ◽  
Wide Range ◽  
Descriptive Method

The growth of snail shells can be described by simple mathematical rules. Variation in a few parameters can explain much of the diversity of shell shapes seen in nature. However, empirical studies of gastropod shell shape variation typically use geometric morphometric approaches, which do not capture this growth pattern. We have developed a way to infer a set of developmentally descriptive shape parameters based on three-dimensional logarithmic helicospiral growth and using landmarks from two-dimensional shell images as input. We demonstrate the utility of this approach, and compare it to the geometric morphometric approach, using a large set of Littorina saxatilis shells in which locally adapted populations differ in shape. Our method can be modified easily to make it applicable to a wide range of shell forms, which would allow for investigations of the similarities and differences between and within many different species of gastropods.

scholarly journals Personality trait differences across types of entrepreneurs: a systematic literature review

2021 ◽  
Author(s):  
Florentine U. Salmony ◽  
Dominik K. Kanbach
Keyword(s):  
Literature Review ◽  
Personality Traits ◽  
Systematic Literature Review ◽  
Empirical Studies ◽  
Academic Research ◽  
Future Research ◽  
Rural Farmers ◽  
Start Up ◽  
Wide Range ◽  
Research Integration

AbstractThe personality traits that define entrepreneurs have been of significant interest to academic research for several decades. However, previous studies have used vastly different definitions of the term “entrepreneur”, meaning their subjects have ranged from rural farmers to tech-industry start-up founders. Consequently, most research has investigated disparate sub-types of entrepreneurs, which may not allow for inferences to be made regarding the general entrepreneurial population. Despite this, studies have frequently extrapolated results from narrow sub-types to entrepreneurs in general. This variation in entrepreneur samples reduces the comparability of empirical studies and calls into question the reviews that pool results without systematic differentiation between sub-types. The present study offers a novel account by differentiating between the definitions of “entrepreneur” used in studies on entrepreneurs’ personality traits. We conduct a systematic literature review across 95 studies from 1985 to 2020. We uncover three main themes across the previous studies. First, previous research applied a wide range of definitions of the term “entrepreneur”. Second, we identify several inconsistent findings across studies, which may at least partially be due to the use of heterogeneous entrepreneur samples. Third, the few studies that distinguished between various types of entrepreneurs revealed differences between them. Our systematic differentiation between entrepreneur sub-types and our research integration offer a novel perspective that has, to date, been widely neglected in academic research. Future research should use clearly defined entrepreneurial samples and conduct more systematic investigations into the differences between entrepreneur sub-types.

Assessment of needs for care among patients with schizophrenic disorders 15 and 17 years after first onset of psychosis

1997 ◽  
Vol 6 (S1) ◽  
pp. 21-28 ◽  
Author(s):  
Durk Wiersma ◽  
Fokko J. Nienhuis ◽  
Cees J. Slooff ◽  
Robert Giel ◽  
Aant De Jong
Keyword(s):  
Mental Disorders ◽  
Empirical Studies ◽  
Signs And Symptoms ◽  
Expected Improvement ◽  
Chronic Patients ◽  
Cross Sectional ◽  
Wide Range ◽  
Social Disablement ◽  
First Onset

Severe and long term mental disorders, like schizophrenia, show in general a wide range of psychiatric signs and symptoms, psychological and physiological impairments and social disablement (Shepherd, 1994; Wing, 1982) reflecting a variety of mental health needs. Many studies provide only a cross-sectional view of the clinical and social problems of the patient population, for example at intake or admission to a mental hospital. Longitudinal studies following patients after discharge for some period of months or years show in general the expected improvement of functioning (e.g. Nienhuis et al., 1994), but as far as only chronic patients are concerned such a positive change is much less noted. The concept of chronicity of mental disorders would presume that after some time needs are fairly predictable and stable and do not change much over time. Our investigation on the long-term course of schizophrenia (Wiersma et al., 1996; 1997) enables us to study over a period of two years, from 15 to 17 years since first onset of psychosis, the stability or variability of needs in schizophrenic disorder. We are not aware of empirical studies on changes in needs among patients with long-term disorders.

Social efficiency of internal affairs bodies

2021 ◽  
Author(s):  
Egor Bunov
Keyword(s):  
Law Enforcement ◽  
Empirical Studies ◽  
Multidimensional Analysis ◽  
Law Enforcement Agencies ◽  
Social Effectiveness ◽  
The Social ◽  
Wide Range ◽  
Degree Of Satisfaction ◽  
Internal Affairs

The monograph contains a theoretical analysis of the social effectiveness of the internal affairs bodies as the degree of satisfaction of the population with the quality of law enforcement activities to protect their interests, rights and freedoms. The results of a multidimensional analysis of empirical studies of the influence of macro - and microsocial factors on the effectiveness of interaction between the population and law enforcement agencies are presented. The article substantiates the criteria for social assessment of the activities of the internal affairs bodies, the use of which allows for practical adjustment of the forms and methods of the management system. For a wide range of readers interested in the practice of applying legal measures of law enforcement.

scholarly journals FRATs: Searching for fast radio transient in real-time with LOFAR

2012 ◽  
Vol 8 (S291) ◽  
pp. 233-233
Author(s):  
Heino Falcke ◽  
Keyword(s):  
Time Scales ◽  
Search Space ◽  
Large Field ◽  
New Radio ◽  
Wide Range ◽  
Imaging Observation ◽  
Previous Decade ◽  
First Results ◽  
Single Radio ◽  
Radio Transients

AbstractLOFAR is an innovative new radio interferometer operating at low radio frequencies from 10 to 270 MHz. It combines a large field-of-view, high fractional bandwidth, rapid response, and a wide range of baselines from tens of meters to thousand kilometers. Its use of phased-array technology and its digital nature make LOFAR an extremely versatile instrument to search for transient radio phenomena on all time scales. Here we discuss in particular the search for fast radio transients (FRATs) at sub-second time scales. In fact, at these time scales the radio sky is rather dynamic due to coherent emission processes. Objects like pulsars, flaring stars, or planets like Jupiter are able to produce bright short flares. For pulsars, most previous detection strategies made use of the rotation of pulsars to detect them, using Fourier techniques, but it is also possible to detect pulsars and other objects through their single pulses. Such surveys have, e.g., led in the previous decade to the detection of Rapid Radio Transients (RRATS), but the unprobed search space is still rather large. LOFAR is now conducting a rather unique survey over the entire northern sky, searching for bright dispersed single radio pulses. This FRATs survey makes use of the LOFAR transient buffer boards (TBBs), which had initially been used to detect nanosecond radio pulses from cosmic rays. The TBBs store the radio data from each single receiver element of LOFAR and allow one to look back in time. A trigger system that runs parallel to normal imaging observation allows one to detect single pulses in an incoherent beam of all LOFAR stations, covering several tens to hundred square degrees at once. Once triggered, the data can be used to localize the pulse and to discriminate cosmic sources from terrestrial interference through 3D localization. The system has been successfully tested with known pulsars and first results of the ongoing survey will be presented.

scholarly journals Consistency and variability between cultures during toddlers’ naturalistic play

2019 ◽  
Author(s):  
Bria Long ◽  
Patrick Wong ◽  
Michael C. Frank ◽  
Eva Lai ◽  
Peggy Chan ◽  
...  
Keyword(s):  
Empirical Studies ◽  
Past Research ◽  
The United States ◽  
Free Play ◽  
Wide Range ◽  
Wide Variability ◽  
Play Behaviors ◽  
Audio Data ◽  
Video And Audio ◽  
Guided Play

Play is a universal behavior that is thought to be a critical way for children to learn a wide range of motor, social, and language skills. Empirical studies of play have borne out some of the predictions of classical theories, showing that children preferentially engage with surprising stimuli, will play in order to learn, and generally show a similar progression of increasingly-complex play behaviors through infancy. Past research has also characterized the types of support and guidance that parents offer during guided play with their child, as distinguished from individual free play. However, most of these studies come from Western nations, and relatively few cross-cultural comparisons have been made, despite observations of wide variability in cultural play traditions. The goal of this study is to examine the variability and consistency of play behaviors in a large sample of 1–2-year-old children—a critical period in the development of play behaviors—in two cultural contexts: the United States and Hong Kong. Our investigation covers both individual and guided play, with measures related to joint attention, stereotypical play behaviors, language use, and types of support offered by caregivers during guided play. This rich, annotated corpus of video and audio data also provides an important resource for research on early play.

scholarly journals EXPRESS: Sources of Variation In Search and Foraging A Theoretical Perspective

2021 ◽  
pp. 174702182110503
Author(s):  
Alastair David Smith ◽  
Carlo De Lillo
Keyword(s):  
Spatial Scales ◽  
Theoretical Perspective ◽  
Search Space ◽  
Visual Exploration ◽  
Two Dimensional ◽  
Search Behaviour ◽  
Wide Range ◽  
Search Processes ◽  
Sources Of Variation ◽  
The Individual

Search – the problem of exploring a space of alternatives in order to identify target goals – is a fundamental behaviour for many species. Although its foundation lies in foraging, most studies of human search behaviour have been directed towards understanding the attentional mechanisms that underlie the efficient visual exploration of two-dimensional scenes. With this review, we aim to characterise how search behaviour can be explained across a wide range of contexts, environments, spatial scales, and populations, both typical and atypical. We first consider the generality of search processes across psychological domains. We then review studies of interspecies differences in search. Finally, we explore in detail the individual and contextual variables that affect visual search and related behaviours in established experimental psychology paradigms. Despite the heterogeneity of the findings discussed, we identify that variations in control processes, along with the ability to regulate behaviour as a function of the structure of search space and the sampling processes adopted, to be central to explanations of variations in search behaviour. We propose a tentative theoretical model aimed at integrating these notions and close by exploring questions that remain unaddressed.

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