scholarly journals TellTail: Fast Scoring and Detection of Dense Subgraphs

2020 ◽  
Vol 34 (04) ◽  
pp. 4150-4157
Author(s):  
Bryan Hooi ◽  
Kijung Shin ◽  
Hemank Lamba ◽  
Christos Faloutsos

Suppose you visit an e-commerce site, and see that 50 users each reviewed almost all of the same 500 products several times each: would you get suspicious? Similarly, given a Twitter follow graph, how can we design principled measures for identifying surprisingly dense subgraphs? Dense subgraphs often indicate interesting structure, such as network attacks in network traffic graphs. However, most existing dense subgraph measures either do not model normal variation, or model it using an Erdős-Renyi assumption - but this assumption has been discredited decades ago. What is the right assumption then? We propose a novel application of extreme value theory to the dense subgraph problem, which allows us to propose measures and algorithms which evaluate the surprisingness of a subgraph probabilistically, without requiring restrictive assumptions (e.g. Erdős-Renyi). We then improve the practicality of our approach by incorporating empirical observations about dense subgraph patterns in real graphs, and by proposing a fast pruning-based search algorithm. Our approach (a) provides theoretical guarantees of consistency, (b) scales quasi-linearly, and (c) outperforms baselines in synthetic and ground truth settings.

Author(s):  
Monika Lewandowska ◽  
Rafał Milner ◽  
Małgorzata Ganc ◽  
Elżbieta Włodarczyk ◽  
Joanna Dołżycka ◽  
...  

AbstractThere are discrepancies in the literature regarding the course of central auditory processes (CAP) maturation in typically developing children and adolescents. The purpose of the study was to provide an overview of age – related improvement in CAP in Polish primary and secondary school students aged 7–16 years. 180 children/adolescents, subdivided into 9 age categories, and 20 adults (aged 18–24 years) performed the Dichotic Digit Test (DDT), Duration Pattern Test (DPT), Frequency Pattern Test (FPT), Gap Detection Test (GDT) and adaptive Speech-in-Noise (aSpN). The 12-year-olds was retested after w week. We found the age effects only for the DDT, DPT and FPT. In the right ear DDT the 7-year-olds performed more poorly than all groups ≥12. In the left ear DDT both 7- and 8-year-olds achieved less correct responses compared with the 13-, 14-, 15-year-olds and with the adults. The right ear advantage was greater in the 7-year-olds than in the 15-year-olds and adult group. At the age of 7 there was lower DPT and FPT scores than in all participants ≥13 whereas the 8-year-olds obtained less correct responses in the FPT than all age categories ≥12. Almost all groups (except for the 7-year-olds) performed better in the DPT than FPT. The test-retest reliability for all tests was satisfactory. The study demonstrated that different CAP have their own patterns of improvement with age and some of them are specific for the Polish population. The psychoacoustic battery may be useful in screening for CAP disorders in Poland.


Author(s):  
Ching-Chang Wong ◽  
Hsuan Ming Feng ◽  
Yu-Cheng Lai ◽  
Hsiang-Yun Chen

This paper designed a 7-DOF redundant robot manipulator that can flexibly and efficiently pick-up random objects. The developed 7-DOF machine with an additional redundancy achieved great progress in terms of flexibility and efficiency in the operational space. A robot operating system (ROS) was used to configure the manipulator system’s software modules, supporting convenient system interface, appropriate movement control policy, and powerful hardware device management for better regulation of the manipulator’s motions. A 3D type Point Cloud Library (PCL) was utilized to perform a novel point cloud image pre-processing method that did not only reduce the point cloud number but also maintained the original quality. The results of the experiment showed that the estimation speed in object detection and recognition procedure improved significantly. The redundant robot manipulator architecture with the two-stage search algorithm was able to find the optimal null space. Suitable parameters in D-H transformation of forward kinematics were selected to efficiently control and position the manipulator in the right posture. Meanwhile, the reverse kinematics estimated all angles of the joints through the known manipulator position, orientation, and redundancy. Finally, motion panning implementation of manipulator rapidly and successfully reached the random object position and automatically drew it up to approximate the desired target.


Sensors ◽  
2021 ◽  
Vol 21 (10) ◽  
pp. 3519
Author(s):  
Yanbing Bai ◽  
Ning Ma ◽  
Shengwang Meng

The largest possible earthquake magnitude based on geographical characteristics for a selected return period is required in earthquake engineering, disaster management, and insurance. Ground-based observations combined with statistical analyses may offer new insights into earthquake prediction. In this study, to investigate the seismic characteristics of different geographical regions in detail, clustering was used to provide earthquake zoning for Mainland China based on the geographical features of earthquake events. In combination with geospatial methods, statistical extreme value models and the right-truncated Gutenberg–Richter model were used to analyze the earthquake magnitudes of Mainland China under both clustering and non-clustering. The results demonstrate that the right-truncated peaks-over-threshold model is the relatively optimal statistical model compared with classical extreme value theory models, the estimated return level of which is very close to that of the geographical-based right-truncated Gutenberg–Richter model. Such statistical models can provide a quantitative analysis of the probability of future earthquake risks in China, and geographical information can be integrated to locate the earthquake risk accurately.


2021 ◽  
Vol 54 (3) ◽  
pp. 1-35
Author(s):  
Matteo Magnani ◽  
Obaida Hanteer ◽  
Roberto Interdonato ◽  
Luca Rossi ◽  
Andrea Tagarelli

A multiplex network models different modes of interaction among same-type entities. In this article, we provide a taxonomy of community detection algorithms in multiplex networks. We characterize the different algorithms based on various properties and we discuss the type of communities detected by each method. We then provide an extensive experimental evaluation of the reviewed methods to answer three main questions: to what extent the evaluated methods are able to detect ground-truth communities, to what extent different methods produce similar community structures, and to what extent the evaluated methods are scalable. One goal of this survey is to help scholars and practitioners to choose the right methods for the data and the task at hand, while also emphasizing when such choice is problematic.


2016 ◽  
Vol 96 (4) ◽  
pp. 589-597 ◽  
Author(s):  
Magdalena Zatoń-Dobrowolska ◽  
Magdalena Moska ◽  
Anna Mucha ◽  
Heliodor Wierzbicki ◽  
Piotr Przysiecki ◽  
...  

This paper demonstrates the influence of artificial selection on morphometric traits in the red fox [Vulpes vulpes (Linnaeus, 1758)]. Measurements and two proportion coefficients were analysed in 132 wild and 199 farm red foxes. The two groups differed significantly (P ≤ 0.05) on all but one of the measurements. Eight out of 11 measurements were significantly greater in the farm fox population, while only tail length, ear height, and length of the right hind limb were greater in the population of wild foxes. The opposite trend was observed when analysing variation in the measurements — the farm foxes were characterized by a greater variability only in the case of body weight, body length, and breadth of chest. When analysing the sexual dimorphism index in different sex and population groups, in almost all analysed traits, the greatest differences occurred between farm males and wild females. All of the traits examined in this study are important for survival of wild foxes. However, because importance of some traits was reduced during domestication and selective breeding (farm foxes do not have to fight for survival), the genetic relationship between them may have weakened. Other possible causes of morphological differences between the studied groups of red foxes are discussed as well.


2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Kochu Therisa Karingada ◽  
Michael Sony

PurposeThe COVID-19 pandemic lockdown has caught many educational institutions by surprise and warranted an abrupt migration from offline to online learning. This has resulted in an education change, without any time for due consideration, as regards its impact on musculoskeletal disorders (MSD) on students. The purpose of this study is to investigate MSD related to online learning during the COVID-19 pandemic lockdown.Design/methodology/approachA cross-sectional study was conducted on undergraduate students in India. In total, 261 students participated in this online survey.FindingsThe study finds that around 80% of students have reported some symptom in the head, neck and eyes since they started online learning. In total, 58% have reported MSD symptom in the right shoulder and 56% in the right hand fingers. Besides, more than 40 % of students experienced some MSD symptoms, in almost all the body parts studied, due to online learning. Correlation analysis is conducted between time spent on online learning per day and MSD symptoms.Originality/valueThis is the first study conducted on MSD and online learning during COVID-19 pandemic.


2021 ◽  
Vol 6 (14) ◽  
pp. 67-81
Author(s):  
Altuğ YENGİNAR

The right to work has been recognized as a fundamental human right in almost all international human rights documents and in the constitutions of many countries. This right has been recognized and guaranteed as a fundamental human right also in the Constitution of the Republic of Turkey. However, not only recognizing and guaranteeing "work" as a fundamental human right but also regulating its implementation and functioning within the framework of laws is of great importance. The concept of overwork is a concept that has been mentioned in the Labor Law regarding the implementation and functioning of the concept of work and it is regulated in our Labor Law No. 4857. In order to talk about overwork, a limited working time is required. In this context, upon determining the maximum number of hours a worker can work per week by drawing a limit on working hours in Labor Law No. 4857, overwork, which is the subject of work exceeding this period, is defined. Furthermore, the types of overwork that arise depending on the reasons for overworking, as well as the jobs that cannot be overworked, are regulated in the same Law.


2021 ◽  
Author(s):  
Kathryn Kost ◽  
◽  
Isaac Maddow-Zimet ◽  
Ashley C. Little

Key Points In almost all U.S. states, pregnancies reported as occurring at the right time or being wanted sooner than they occurred comprised the largest share of pregnancies in 2017, though proportions varied widely by state. The proportion of pregnancies that were wanted later or unwanted was higher in the South and Northeast than in other regions, and the proportion of pregnancies that occurred at the right time or were wanted sooner was higher in the West and Midwest. From 2012 to 2017, the wanted-later-or-unwanted pregnancy rate fell in the majority of states. However, no clear pattern emerged for any changes in the rate of pregnancies that were reported as wanted then or sooner or in the rate of those for which individuals expressed uncertainty.


Author(s):  
Frederico M. Batista ◽  
Ana Grade ◽  
Deborah M. Power ◽  
Francisco Ruano ◽  
Elizabeth M. Harper

The occurrence of pearls in the ‘true’ oysters, the Ostreioidea, is poorly documented despite being the most produced mollusc species in the world. Oysters of the Crassostrea genus were collected in two different sites in southern Portugal where both Crassostrea angulata and C. gigas are present, namely in: (1) the Ria Formosa lagoon where pearls were not observed (N = 446); and (2) the Guadiana estuary where pearls were found in 12 out of the 798 oysters analysed. The pearls were located mainly at the edge of the right mantle lobe in the inhalant chamber and their maximum length ranged from 0.9 to 5.5 mm. Almost all the pearls had a white-cream colouration with the exception of two pearls that had a black-brown colour. X-ray diffraction analysis of one pearl showed that it was entirely calcitic with no traces of either aragonite or vaterite. The pearls observed were therefore non-nacreous pearls. Scanning electron microscopy (SEM) revealed a diversity of microstructures including prismatic, foliae-like sheets and blocky textures, i.e. highly reminiscent of the host oyster shell microstructures. Parasites (e.g. parasitic copepods, Haplosporidium-like plasmodia) and signs of diseases (e.g. foot disease) were observed in some of the oysters analysed, but they were not associated with the occurrence of pearls. The present work is one of the few studies on the occurrence of natural pearls in ‘true’ oysters and to our knowledge the first description of their microstructure by SEM.


2019 ◽  
Vol 9 (2) ◽  
pp. 76
Author(s):  
Muhammad Tawary ◽  
Julius Pontoh ◽  
Lydia Momuat

Analisis Kandungan Klorofil Pada Anak Daun Tanaman Kelapa (Analysis of Chlorophyll Content in Children Leaves of Coconut Plants) Muhammad Tawary1*), Julius Pontoh1), Lydia I.Momuat1)1)Jurusan Kimia, FMIPA UNSRAT Manado*Email korespondensi: [email protected] Diterima 7 Juli 2019, diterima untuk dipublikasi 10 Agustus 2019 Abstrak Tanaman kelapa banyak dibudidayakan sebagai tanaman pertanian. Tanaman kelapa memiliki nilai ekonomi yang tinggi karena hampir semua bagian tanaman kelapa memiliki manfaat ekonomis. Penelitian bertujuan untuk  mengembangkan metode analisis klorofil pada daun dan menentukan bagian anak daun yang memiliki kandungan klorofil tertinggi. Analisis kandungan klorofil dilakukan dengan metode ektraksi pelarut yang absorbansinya dibaca pada spektrofotometer UV-Vis. Kandungan klorofil a dalam daun bervariasi pada setiap bagian anak daun tanaman kelapa. Kandungan klorofil a pada posisi tengah anak daun kelapa (763.19 µmol/m2) dan kandungan klorofil b (196.22 µmol/m2). Kandungan klorofil a dan b pada setiap bagian anak daun dan posisi kanan dan kiri anak daun memiliki nilai yang relatif sama.Kata kunci: Kelapa, klorofil a, klorofil b Abstract Many coconut plants are cultivated as agricultural crops. Coconut plants have high economic value because almost all parts of coconut plants have economic benefits. The study aims to develop a method of chlorophyll analysis on leaves and determine the part of leaflets which have the highest chlorophyll content. Analysis of chlorophyll content was carried out by a solvent extraction method in which the absorbance was read in a UV-Vis spectrophotometer. The content of chlorophyll a in leaves varies with each part of the leaves of the coconut plant. Chlorophyll a content in the middle position of coconut leaf child (763.19 µmol / m2) and chlorophyll b content (196.22 µmol / m2). The content of chlorophyll a and b in each part of the leaf child and the right and left positions of the leaves have relatively the same value.Keywords: Coconut, Chlorophyll a, Chlorophyll b


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