Environmental effects on halo abundance and weak lensing peak statistics towards large underdense regions

ABSTRACT The cosmic microwave background (CMB) contains an anomalous cold spot with a surrounding hot ring, known as the Cold Spot. Inoue & Silk proposed that this feature could be explained by postulating a supervoid: if such a large underdense region exists, then the growth of matter perturbing around the spot might differ from the average value in the Universe and the differences might affect weak lensing analysis of peak statistics. To investigate environmental effects on halo number count and peak statistics, we used a publicly available ray-tracing simulation for a box size of 2250 h−1 Mpc on a side. We found that the number count for massive haloes towards the largest underdense region in the simulation decreases and the corresponding significance of the difference, based on a cosmic average, is ≥3σ. On the basis of the results of peak statistics analysis, the number of high peaks decreases with the decrement of massive haloes, but the number of low peaks increases with the lack of matter in the line of sight. The highest significance of the decrement in peak counts in large underdense regions is 5σ in the total signal-to-noise ratio. Our result implies that environmental effects on halo abundance and weak lensing peak statistic can be used to probe the presence and properties of supervoids.

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Galaxy clusters as intrinsic alignment tracers: present and future

Monthly Notices of the Royal Astronomical Society ◽

10.1093/mnras/staa3633 ◽

2020 ◽

Vol 500 (4) ◽

pp. 5561-5569

Author(s):

C J G Vedder ◽

N E Chisari

Keyword(s):

Large Scale ◽

Signal To Noise Ratio ◽

Sloan Digital Sky Survey ◽

Line Of Sight ◽

Expected Number ◽

Number Count ◽

Sky Survey ◽

Redshift Survey ◽

Number Counts ◽

The Universe

ABSTRACT Galaxies and clusters embedded in the large-scale structure of the Universe are observed to align in preferential directions. Galaxy alignment has been established as a potential probe for cosmological information, but the application of cluster alignments for these purposes remains unexplored. Clusters are observed to have a higher alignment amplitude than galaxies, but because galaxies are much more numerous, the trade-off in detectability between the two signals remains unclear. We present forecasts comparing cluster and galaxy alignments for two extragalactic survey set-ups: a currently available low-redshift survey (Sloan Digital Sky Survey, SDSS) and an upcoming higher redshift survey (Legacy Survey of Space and Time, LSST). For SDSS, we rely on the publicly available redmapper catalogue to describe the cluster sample. For LSST, we perform estimations of the expected number counts while we extrapolate the alignment measurements from SDSS. Clusters in SDSS have typically higher alignment signal-to-noise ratio (S/N) than galaxies. For LSST, the cluster alignment signals quickly wash out with redshift due to a relatively low number count and a decreasing alignment amplitude. Nevertheless, a potential strong suit of clusters is in their interplay with weak lensing: intrinsic alignments can be more easily isolated for clusters than for galaxies. The S/N of cluster alignment can in general be improved by isolating close pairs along the line of sight.

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A Maximum-Minimum Filtering Algorithm Base on Threshold

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.236-237.1101 ◽

2012 ◽

Vol 236-237 ◽

pp. 1101-1105

Author(s):

Hong She Dang ◽

Li Na Tian ◽

Fang Zhang

Keyword(s):

Signal To Noise Ratio ◽

Filtering Algorithm ◽

Average Value ◽

Noise Point ◽

Pixel Value ◽

The Difference ◽

Algorithm Base ◽

Salt And Pepper ◽

Image Detail ◽

Maximum Minimum

In allusion to the contradiction between salt-and-pepper noise attenuation and image detail-preserving, a maximum-minimum filtering algorithm base on threshold is proposed in this paper. The gray values of the pixels in the filtering windows are given firstly. If the test pixel value is the extreme value of the filtering windows, this pixel is a suspicious noise point. And then sort the absolute value of the difference between the suspicious noise point value and pixels gray value in its neighborhood. Judge the pixel is a real noise point according to the average value of the middle two values in the difference sequence. The original gray value of noise point is determined by the maximum-minimum relationship between the pixel values of the neighborhood. If the pixel is not a noise point, its value is kept. The simulation results show that the proposed algorithm has greatly impact on signal to noise ratio and mean square error which retains more image details while making sure to remove noise.

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Detection of Anisotropy in the Cosmic Microwave Background at Horizon and Sub-Horizon Scales with the BOOMERanG Experiment

Symposium - International Astronomical Union ◽

10.1017/s0074180900216100 ◽

2005 ◽

Vol 201 ◽

pp. 55-64

Author(s):

P. de Bernardis ◽

P. A. R. Ade ◽

J. J. Bock ◽

J. R. Bond ◽

J. Borrill ◽

...

Keyword(s):

Total Mass ◽

Signal To Noise Ratio ◽

Cosmological Parameters ◽

Power Spectra ◽

High Signal ◽

Mass Energy ◽

Microwave Background ◽

Technical Advances ◽

The Universe

BOOMERanG has recently resolved structures on the last scattering surface at redshift ˜ 1100 with high signal to noise ratio. We review the technical advances which made this possible, and we focus on the current results for maps and power spectra, with special attention to the determination of the total mass-energy density in the Universe and of other cosmological parameters.

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The Effect of Jigsaw Methode and Motivation on Students’ of Learning Outcomes

Budapest International Research and Critics in Linguistics and Education (BirLE) Journal ◽

10.33258/birle.v3i1.749 ◽

2020 ◽

Vol 3 (1) ◽

pp. 20-30

Author(s):

Yunita Yunita ◽

Hidayat Hidayat ◽

Harun Sitompul

Keyword(s):

Cooperative Learning ◽

Student Learning ◽

Learning Outcomes ◽

Student Learning Outcomes ◽

Learning Motivation ◽

Learning Approaches ◽

High Learning ◽

Average Value ◽

The Difference ◽

Low Motivation

This study aims to: (1) investigate the effect of Jigsaw cooperative learning on students learning outcomes; (2) find the difference in learning outcomes between high and low learning motivation and (3) find the interaction between learning approaches and learning motivation towards learning outcomes. The population of the study is students of grade IVa, IVb, IVc at SD Kasih Ibu Patumbak and the sample in this study is grade IVa with 35 students and grade IVb with 35 students. The results show that: (1) the average student learning outcomes of jigsaw cooperative learning is 28.40 while conventional is 24.14. Thus, students learning outcomes that get cooperative learning of jigsaw type are higher than conventional learning, (2) Students who have high motivation get an average value = 30.74, while low motivation is 22.72. Thus, it can be concluded that there are differences in student learning outcomes having high learning motivation and low learning motivation, and (3) students learning outcomes taught by jigsaw cooperative learning are high learning motivation groups (32.94), and low learning motivation groups (24.58), while students taught with conventional learning are high learning motivation groups (28.40 ), and low motivation groups (20,95). Thus, there is no interaction between learning approaches and learning motivation towards learning outcomes.

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Pengaruh Jumlah Pencucian Beras dengan Kadar Klorin

Jurnal Laboratorium Khatulistiwa ◽

10.30602/jlk.v1i1.102 ◽

2017 ◽

Vol 1 (1) ◽

pp. 89

Author(s):

Indah Purwaningsih ◽

Supriyanto Supriyanto

Keyword(s):

Mucous Membrane ◽

Confidence Level ◽

Iodometric Titration ◽

Titration Method ◽

Anova Test ◽

Average Value ◽

Significant Difference ◽

The Difference

Abstract: Chlorine is a green halogen-shaped halogen gas at normal temperature and serves as bleach, stain remover and disinfectant. Chlorine is now widely used for bleaching rice so that less quality rice looks like quality rice. Chlorine is very toxic and causes mucous membrane irritation, highly reactive and very powerful oxidizer. The purpose of this research was to determine the difference of chlorine level in chlorinated rice washed once, twice and 3 times. The sample in this study amounted to 11 samples calculated by replication formula. Each sample was treated 3 times, ie 1 washed once, 2 washed twice and washed 3 times. The samples then examined by iodometric titration method. Based on the results of the study using ANOVA test, 11 samples obtained the average value of chlorine after washed once amount of 0.0176%, after washed twice amount of 0.0111%, and after washed 3 times amount of 0.0052% with the value significance p = 0.03 (p <0.05) at 95% confidence level which means there was a significant difference between chlorine levels in chlorinated rice washed once, twice and 3 times.Abstrak: Klorin merupakan unsur halogen berbentuk gas berwarna kuning kehijauan pada suhu normal danberfungsi sebagai pemutih, penghilang noda maupun desinfektan. Klorin sekarang banyak digunakan untuk bahan pemutih beras agar beras yang kurang berkualitas tampak seperti beras berkualitas. Klorin sangat toksik dan menyebabkan iritasi membran mukosa, sangat reaktif dan merupakan oksidator yang sangat kuat. Tujuan dari penelitian ini ialah untuk mengetahui perbedaan kadar klorin pada beras berklorin yang dicuci sebanyak 1 kali, 2 kali dan 3 kali. Sampel dalam penelitian ini berjumlah 11 sampel yang dihitung dengan rumus replikasi. Setiap sampel diberi perlakuan sebanyak 3 kali, yaitu 1 kali pencucian, 2 kali pencucian dan 3 kali pencucian. Sampel penelitian kemudian diperiksa dengan metode titrasi iodometri. Berdasarkan hasil penelitian menggunakan uji Anova secara komputerisasi terhadap 11 sampel diperoleh nilai rata-rata kadar klorin setelah 1 kali pencucian sebesar 0,0176 %, setelah 2 kali pencucian sebesar 0,0111 %, dan setelah 3 kali pencucian sebesar 0,0052 % dengan nilai signifkansi p = 0,03 (p<0,05) pada tingkat kepercayaan 95% yang artinya ada perbedaan yang bermakna antara kadar klorin pada beras berklorin yang dicuci sebanyak 1 kali, 2 kali dan 3 kali.

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Results of studying the dimensional accuracy of the bases of complete removable prostheses made using 3D printing and traditional technologies

Стоматология для всех ◽

10.35556/idr-2020-4(93)34-39 ◽

2020 ◽

pp. 34-39

Author(s):

Vokulova Yu.A. Vokulova ◽

E.N. Zhulev

Keyword(s):

3D Printing ◽

Traditional Method ◽

Laser Scanning ◽

Laser Scanner ◽

Digital Technologies ◽

Dimensional Accuracy ◽

3D Printer ◽

Significance Level ◽

Average Value ◽

The Difference

This article presents the results of studying the dimensional accuracy of the bases of complete removable prostheses made using a 3D printer and the traditional method. Bases of complete removable prostheses were made using an intraoral laser scanner iTero Cadent (USA) and a 3D printer Asiga Max UV (Australia). To study the dimensional accuracy of the bases of complete removable prostheses, we used the DentalCAD 2.2 Valletta software. The Nonparametric Wilcoxon W-test was used for statistical analysis of the obtained data. We found that the average value of the difference with the standard for bases made using digital technologies is 0.08744±0.0484 mm. The average value of the difference with the standard for bases made by the traditional method is 0.5654±0.1611 mm. Based on these data, we concluded that the bases of complete removable prostheses made using modern digital technologies (intraoral laser scanning and 3D printer) have a higher dimensional accuracy compared to the bases of complete removable prostheses made using the traditional method with a significance level of p<0.05 (Wilcoxon's W-test=0, p=0.031). Keywords: digital technologies in dentistry, digital impressions, intraoral scanner, 3D printing, ExoCAD, complete removable dentures.

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The experience of employment of the mathematical cartography methods in cosmology

Geodesy and Cartography ◽

10.22389/0016-7126-2017-923-5-7-16 ◽

2017 ◽

Vol 923 (5) ◽

pp. 7-16

Author(s):

A.V. Kavrayskiy

Keyword(s):

Background Radiation ◽

Three Dimensional ◽

Spherical Coordinates ◽

Linear Element ◽

Microwave Background ◽

Euclidian Space ◽

Microwave Background Radiation ◽

Rectangular Coordinates ◽

The Universe ◽

Length Distortion

The experience of mathematical modeling of the 3D-sphere in the 4D-space and projecting it by mathematical cartography methods in the 3D-Euclidian space is presented. The problem is solved by introduction of spherical coordinates for the 3D-sphere and their transformation into the rectangular coordinates, using the mathematical cartography methods. The mathematical relationship for calculating the length distortion mp(s) of the ds linear element when projecting the 3D-sphere from the 4-dimensional Euclidian space into three-dimensional Euclidian space is derived. Numerical examples, containing the modeling of the ds small linear element by spherical coordinates of 3D-sphere, projecting this sphere into the 3D-Euclidian space and length of ds calculating by means of its projection dL and size of distortion mp(s) are solved. Based on the model of the Universe known in cosmology as the 3D-sphere, the hypothesis of connection between distortion mp(s) and the known observed effects Redshift and Microwave Background Radiation is considered.

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Investigating the properties of a galaxy group at z = 0.6

Proceedings of the International Astronomical Union ◽

10.1017/s1743921320001945 ◽

2020 ◽

Vol 15 (S359) ◽

pp. 188-189

Author(s):

Daniela Hiromi Okido ◽

Cristina Furlanetto ◽

Marina Trevisan ◽

Mônica Tergolina

Keyword(s):

Large Scale ◽

The Other ◽

Numerical Density ◽

Spectroscopy Data ◽

Stellar Kinematics ◽

Galaxy Groups ◽

The Galaxy ◽

The Difference ◽

The Impact ◽

The Universe

AbstractGalaxy groups offer an important perspective on how the large-scale structure of the Universe has formed and evolved, being great laboratories to study the impact of the environment on the evolution of galaxies. We aim to investigate the properties of a galaxy group that is gravitationally lensing HELMS18, a submillimeter galaxy at z = 2.39. We obtained multi-object spectroscopy data using Gemini-GMOS to investigate the stellar kinematics of the central galaxies, determine its members and obtain the mass, radius and the numerical density profile of this group. Our final goal is to build a complete description of this galaxy group. In this work we present an analysis of its two central galaxies: one is an active galaxy with z = 0.59852 ± 0.00007, while the other is a passive galaxy with z = 0.6027 ± 0.0002. Furthermore, the difference between the redshifts obtained using emission and absorption lines indicates an outflow of gas with velocity v = 278.0 ± 34.3 km/s relative to the galaxy.

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Anisotropy of the Microwave Background and Biased Galaxy Formation

Symposium - International Astronomical Union ◽

10.1017/s0074180900135831 ◽

1988 ◽

Vol 130 ◽

pp. 43-50

Author(s):

Nick Kaiser

Keyword(s):

Galaxy Formation ◽

Large Scale ◽

Microwave Background ◽

Galaxy Clustering ◽

Clear View ◽

Hot Gas ◽

Density Perturbations ◽

The Universe ◽

Theoretical Developments

Fluctuations in the microwave background will have been imprinted at z ≃ 1000, when the photons and the plasma decoupled. On angular scales greater than a few degrees these fluctuations provide a clear view of any primordial density perturbations, and therefore a clean test of theories which invoke such fluctuations from which to form the structure we see in the universe. On smaller angular scales the predictions are less certain: reionization of the gas may modify the spectrum of the primordial fluctuations, and secondary fluctuations may be generated.Here I shall review some recent theoretical developments. A brief survey is made of the currently popular theories for the primordial perturbations, with emphasis on the predictions for large scale anisotropy. One major uncetainty in the predictions arises from the normalisation of the fluctuations to e.g. galaxy clustering, and much attention is given to the question of ‘biased’ galaxy formation. The effect of reionization on the primordial fluctuations is discussed, as is the anisotropy generated from scattering off hot gas in clusters, groups and galaxies.

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