scholarly journals U-Pb geochronology by zircon of fine-grained granite of the Osnitsky complex. (Volinsky megablok US)

2020 ◽  
Vol 41 ◽  
pp. 83-86
Author(s):  
O.B. Vysotsky ◽  
◽  
L.M. Stepanyuk ◽  
T.I. Dovbush ◽  
N.O. Kovalenko ◽  
...  
Keyword(s):  
Lead Isotope ◽  
Weighted Average ◽  
Coarse Grained ◽  
Isotopic Age ◽  
Fine Grained ◽  
Average Value ◽  
Second Stage ◽  
Two Stages ◽  
Isotope Dating ◽  
Uranium Lead Dating

The article presents the results of uranium-lead dating of zircon from fine-grained granite of the Osnytsia block of the Volyn megablock of the Ukrainian Shield. The variety of granites of the Osnitsky complex is manifested starting from their appearance. They are dominated by massive medium-grained rocks, limitedly developed fine-grained, even less common coarse-grained varieties. The age of typical Osnitsky granites, determined by the uranium-lead method according to zircon, is 1980-1950 million years. Granitoids after gabbroids were formed, and their rooting took place in two stages. At the first stage, depending on the physicochemical and tectonic conditions, a whole range of acid rocks was formed – from leptitelike (fine-grained) to large-medium-grained granites. In the second stage, coarse-grained, typical Osnitsky granites took root. One of the most characteristic macroscopic features of Osnitsky granites is that quartz is almost always represented by lilac-gray rounded grains. According to the results of uranium-lead isotope dating, the age of zircon from fine-grained granite is 1973.6 ± 8.4 million years, and 14 ± 24 million years, according to the lower. The weighted average value of the isotopic age in the isotope ratio 207Pb/206Pb is 1969.3 ± 6 million years. The obtained age for zircon from fine-grained granite of the Osnitsky complex corresponds to the time of formation of granites of the Osnitsky block.

scholarly journals Morphing and Sampling Network for Dense Point Cloud Completion

2020 ◽  
Vol 34 (07) ◽  
pp. 11596-11603 ◽  
Author(s):  
Minghua Liu ◽  
Lu Sheng ◽  
Sheng Yang ◽  
Jing Shao ◽  
Shi-Min Hu
Keyword(s):  
Point Cloud ◽  
Point Clouds ◽  
Coarse Grained ◽  
Second Stage ◽  
The Earth ◽  
Novel Approach ◽  
Dense Point ◽  
Chamfer Distance ◽  
Structural Loss ◽  
Two Stages

3D point cloud completion, the task of inferring the complete geometric shape from a partial point cloud, has been attracting attention in the community. For acquiring high-fidelity dense point clouds and avoiding uneven distribution, blurred details, or structural loss of existing methods' results, we propose a novel approach to complete the partial point cloud in two stages. Specifically, in the first stage, the approach predicts a complete but coarse-grained point cloud with a collection of parametric surface elements. Then, in the second stage, it merges the coarse-grained prediction with the input point cloud by a novel sampling algorithm. Our method utilizes a joint loss function to guide the distribution of the points. Extensive experiments verify the effectiveness of our method and demonstrate that it outperforms the existing methods in both the Earth Mover's Distance (EMD) and the Chamfer Distance (CD).

scholarly journals The Camarat granite (Maures Massif, SE France): a tectonic marker of the late orogenic evolution of the South European Variscan Belt

2020 ◽  
Author(s):  
Olivier Bolle ◽  
Michel Corsini ◽  
Hervé Diot ◽  
Oscar Laurent ◽  
Raphaël Melis
Keyword(s):  
Weighted Average ◽  
Shear Zones ◽  
Strike Slip ◽  
Coarse Grained ◽  
Variscan Belt ◽  
Tectonic Event ◽  
Upper Carboniferous ◽  
Fine Grained ◽  
Two Samples ◽  
Maures Massif

<p>A significant portion of the Maures-Tanneron Massif (SE branch of the European Variscan Belt) is occupied by late orogenic, anatectic crustal granitoids that were emplaced at ca. 325-300 Ma (Upper Carboniferous)<sup>1,2</sup>. The Camarat granite<sup>3</sup> is one of the smallest representatives of these granitoids (~2.5 km<sup>2</sup>). It is a composite intrusion exposed in migmatitic gneisses of the Maures Massif, along the southern shore of the Saint-Tropez Peninsula. From west to east, it consists of an E-W strip of Ms-Bt-Crd leucogranite where coarse- and fine-grained facies are found in similar amounts, and two bodies of Bt-Ms leucogranite, dominantly coarse-grained.</p><p>Zircon and monazite from two samples of the Camarat granite have been analyzed by LA-ICP-MS for U-Pb dating. Sixteen monazite analyses from the fine-grained facies of the E-W granite strip give a Concordia age of 303.5 ± 1.8 Ma (2 S.E., MSWD = 0.9). Sixteen zircons from the coarse-grained facies of the easternmost intrusion provide a Concordia age of 304.6 ± 2.1 Ma (2 S.E., MSWD = 1.2). The two dates are identical within uncertainty and are considered to constrain crystallization of the Camarat granite at ~304 Ma (Kasimovian–Gzhelian limit).</p><p>Twenty-one measurements of the anisotropy of magnetic susceptibility (AMS) and direct textural quantifications through image analysis (IA) of 10 samples give agreeing results that reveal the fabric orientation in the Camarat granite. The foliation has a variable orientation, with a weighted average of N65°E/26°NNW for the AMS data and N77°E/17°NNW for the IA data (D = 10°). The lineation pattern is more homogeneous, displaying a consistent northerly shallow plunge (mean of N12°E/22°NNE vs. N22°E/20°NNE; D = 10°). The Camarat granite lineations are parallel to lineations in the gneissic country rocks. These were produced during the last Variscan tectonic event evidenced in the area, a partitioned transpression phase, localized along ca. N-S sinistral strike-slip shear zones<sup>4</sup>. It is proposed that the ascent of the Camarat granite was favoured by such strike-slip structures and that pull-aparts represent the sites of emplacement, as best exemplified by the E-W granite strip.</p><p>In the Corso-Sardinian Block, another portion of the SE Variscides formerly juxtaposed to the Maures-Tanneron Massif<sup>5</sup>, a model of progressive transition from orogen-parallel flow (late orogenic, Upper Carboniferous transpression) to orogen-perpendicular extension (post orogenic, Permian rifting) has been recently proposed<sup>6</sup>. Such a model may be extended to other areas of the SE Variscan Belt, in particular to the Maures-Tanneron Massif which is cut and bordered by ca. E-W Permian grabens<sup>7</sup>, implying that a ca. N-S direction of stretching, as recorded by the 304 Ma Camarat granite, was still prevailing in Permian times.</p><p> </p><ol><li>Duchesne et al., Lithos 162-163, 195-220 (2013). 2. Schneider et al., Geol. Soc. Spec. Pub. 405, 313-331 (2014). 3. Amenzou & Pupin, C. R. Acad. Sc. Paris (Série II) 303, 697-700 (1986). 4. Corsini & Rolland, C. R. Geoscience 341, 214-223 (2009). 5. Edel et al., Geol. Soc. Spec. Pub. 405, 333-361 (2014). 6. Casini et al., Tectonophysics 646, 65-78 (2015). 7. Toutin-Morin, Ann. Soc. géol. Nord 106, 183-187 (1987).</li> </ol>

Two Stages of Curve Detection Suggest Two Styles of Visual Computation

1989 ◽  
Vol 1 (1) ◽  
pp. 68-81 ◽  
Author(s):  
Steven W. Zucker ◽  
Allan Dobbins ◽  
Lee Iverson
Keyword(s):  
Computer Vision ◽  
Visual Images ◽  
Fine Grained ◽  
Second Stage ◽  
Visual Systems ◽  
Local Description ◽  
Curve Detection ◽  
Two Stages

The problem of detecting curves in visual images arises in both computer vision and biological visual systems. Our approach integrates constraints from these two sources and suggests that there are two different stages to curve detection, the first resulting in a local description, and the second in a global one. Each stage involves a different style of computation: in the first stage, hypotheses are represented explicitly and coarsely in a fixed, preconfigured architecture; in the second stage, hypotheses are represented implicitly and more finely in a dynamically constructed architecture. We also show how these stages could be related to physiology, specifying the earlier parts in a relatively fine-grained fashion and the later ones more coarsely.

scholarly journals Error annotation in the COPLE2 corpus

2018 ◽  
pp. 225-239
Author(s):  
Iria Del Rio ◽  
Amália Mendes
Keyword(s):  
Second Language Acquisition ◽  
Coarse Grained ◽  
Computer Assisted ◽  
Learner Corpus ◽  
Fine Grained ◽  
Error Annotation ◽  
Level Information ◽  
New Research ◽  
Two Stages ◽  
General Architecture

We present the general architecture of the error annotation system applied to the COPLE2 corpus, a learner corpus of Portuguese implemented on the TEITOK platform. We give a general overview of the corpus and of the TEITOK functionalities and describe how the error annotation is structured in a two-level system: first, a fully manual token-based and coarse-grained annotation is applied and produces a rough classification of the errors in three categories, paired with multi-level information for POS and lemma; second, a multi-word and fine-grained annotation in standoff is then semi-automatically produced based on the first level of annotation. The token-based level has been applied to 47% of the total corpus. We compare our system with other proposals of error annotation, and discuss the fine-grained tag set and the experiments to validate its applicability. An inter-annotator (IAA) experiment was performed on the two stages of our system using Cohen’s kappa and it achieved good results on both levels. We explore the possibilities offered by the tokenlevel error annotation, POS and lemma to automatically generate the fine-grained error tags by applying conversion scripts. The model is planned in such a way as to reduce manual effort and rapidly increase the coverage of the error annotation over the full corpus. As the first learner corpus of Portuguese with error annotation, we expect COPLE2 to support new research in different fields connected with Portuguese as second/foreign language, like Second Language Acquisition/Teaching or Computer Assisted Learning.

Strength and Plasticity of Ultra-Fine Grained Zirconium at Low Temperatures

2008 ◽  
Vol 584-586 ◽  
pp. 452-457
Author(s):  
Elena D. Tabachnikova ◽  
Aleksey V. Podolskiy ◽  
Vladimir Z. Bengus ◽  
S.N. Smirnov ◽  
V.D. Natsik ◽  
...  
Keyword(s):  
Considerable Increase ◽  
Activation Volume ◽  
Mutual Influence ◽  
Large Strain ◽  
Coarse Grained ◽  
Simultaneous Action ◽  
Fine Grained ◽  
Grain Sizes ◽  
Strength And Plasticity ◽  
Two Stages

Plasticity of ultra-fine grained (UFG) zirconium (grain size ~ 0.4 µm), produced by intensive plastic deformation (IPD) - a combination of extrusion, annealing, and drawing, have been studied within the temperature range 300 – 4.2 K in uniaxial compression. It was found that decrease of grain sizes in the result of IPD leads to considerable increase of strength characteristics for the UFG zirconium in comparison with coarse-grained (CG) zirconium (in 6 times at 300 K and 4 times at 77 K); and plasticity of the UFG zirconium keeps rather large (strain > 0.15). Two stages of the strain-hardening and decrease of the activation volume for plastic flow with deformation have been registered. A conclusion was made about the identity of basic deformation mechanisms in the UFG and CG zirconium: simultaneous action and mutual influence of intragrain dislocation gliding and twinning.

scholarly journals Petrography, microthermometry, and isotopy of the gold veins from Vetas, Santander (Colombia)

2020 ◽  
Vol 24 (1) ◽  
pp. 5-18
Author(s):  
Sonia Rojas Barbosa ◽  
Juan Carlos Molano ◽  
Thomas Cramer
Keyword(s):  
Fluid Inclusions ◽  
Gold Mineralization ◽  
Coarse Grained ◽  
Fine Grained ◽  
Quartz Veins ◽  
Low Salinity ◽  
Second Stage ◽  
The Third ◽  
Jurassic Rocks ◽  
Low Sulfidation

The gold mineralization located in Vetas, Santander, consists of auriferous quartz veins hosted in Bucaramanga gneiss rocks, intrusive Jurassic rocks, and intrusive to porphyritic Miocene rocks. This study identified four mineralizing events: (1). Sericite, carbonate (ankerite and calcite?), massive and microcrystalline quartz, sphalerite, adularia, albite, galena, thin pyrite, pyrrhotite, chalcopyrite. The age for this stage is 10.78 ±0.23Ma (Ar/Ar on sericite). (2). Molybdenite, magnetite with exsolution of ilmenite, As-pyrite, sphalerite, fine-grained pyrite and little chalcopyrite quartz with huge, feathery, fine mosaic, flamboyant and microcrystalline textures and, tourmaline and sericite. (3). Gold and tennantite associated with sphalerite, fine- and coarse-grained pyrite, As-pyrite, chalcopyrite like inclusions, and quartz with flamboyant, mosaic, massive and “comb” textures, and tourmaline. Stage 2 and 3 happened from 7.58 ±0.15 Ma to 6,89±0,41Ma (Ar/Ar on sericite). (4). Thick, thin, and pyrite with arsenic, hematite and microcrystalline quartz (forming breccia texture), and sericite. The age for this stage is 5.24 ±0.10 (Ar/Ar on sericite). Post-mineral: quartz comb, alunite, halloysite, kaolinite, and ferrum hydroxides. The stable isotopes, ∂18O, ∂D, and ∂34S and fluid inclusions analysis infer that fluids were producing a mixture of meteoric and magmatic fluids with low salinity and minimum trapping temperatures between 200°C to 390°C. The mineralogy association, and fluid inclusions, in the first event show characteristic of low sulfidation epithermal. The second stage was hottest and with more magmatic signature over printed an intermediate sulfidation system; show a little more salinity on the fluids and more mineralogical diversity, the third and four events, could show an evolution of this fluid, where it was cooling and impoverishing on metals. Two initials stages are contemporaneous with two magmatic Miocene pulses on the area: the first one of granodiorite composition 10, 9± 0.2 Ma (U/Pb zircon), and the other one rhyodacite with 8.4 ±0.2 y 9.0 ± 0.2 Ma.

scholarly journals Error annotation in the COPLE2 corpus

2019 ◽  
pp. 225-239
Author(s):  
Iria Del Rio ◽  
Amália Mendes
Keyword(s):  
Second Language Acquisition ◽  
Coarse Grained ◽  
Computer Assisted ◽  
Learner Corpus ◽  
Fine Grained ◽  
Error Annotation ◽  
Level Information ◽  
New Research ◽  
Two Stages ◽  
General Architecture

We present the general architecture of the error annotation system applied to the COPLE2 corpus, a learner corpus of Portuguese implemented on the TEITOK platform. We give a general overview of the corpus and of the TEITOK functionalities and describe how the error annotation is structured in a two-level system: first, a fully manual token-based and coarse-grained annotation is applied and produces a rough classification of the errors in three categories, paired with multi-level information for POS and lemma; second, a multi-word and fine-grained annotation in standoff is then semi-automatically produced based on the first level of annotation. The token-based level has been applied to 47% of the total corpus. We compare our system with other proposals of error annotation, and discuss the fine-grained tag set and the experiments to validate its applicability. An inter-annotator (IAA) experiment was performed on the two stages of our system using Cohen’s kappa and it achieved good results on both levels. We explore the possibilities offered by the tokenlevel error annotation, POS and lemma to automatically generate the fine-grained error tags by applying conversion scripts. The model is planned in such a way as to reduce manual effort and rapidly increase the coverage of the error annotation over the full corpus. As the first learner corpus of Portuguese with error annotation, we expect COPLE2 to support new research in different fields connected with Portuguese as second/foreign language, like Second Language Acquisition/Teaching or Computer Assisted Learning.

scholarly journals Pemanfaatan Tanaman Hias Sebagai Media Pembelajaran Biologi

2020 ◽  
Vol 1 (1) ◽  
pp. 8-14
Author(s):  
Lia Angela ◽  
Husnin Nahry Yarza ◽  
Toni Haryanto ◽  
Nisa Novita Putri
Keyword(s):  
School Environment ◽  
Survey Methods ◽  
Descriptive Analysis ◽  
Ornamental Plants ◽  
Ornamental Plant ◽  
Average Value ◽  
Second Stage ◽  
Photo Album ◽  
Two Stages ◽  
School Yard

The research aims to determine the types of ornamental plants found in the SMP Negeri 11 Sungai Penuh school environment. This research was conducted in two stages: the first stage was identifying ornamental plant species found in the school yard and made as learning media in the form of a photo album. The second stage applies the identification results in the form of photo album media in biology learning. The method used in this study, in the first stage uses descriptive analysis with survey methods and the second stage uses quantitative analysis. The instruments used in this study were questionnaires, key books of determination and photos of plants from internet references. The results of this study were found 19 types of ornamental plants found in the school yard of SMP Negeri 11 Sungai Penuh and the dominant ornamental plant is the type of Araceae. The results of student responses to the ornamental plant media obtained an average value of 89.3% with a very good category.

scholarly journals DEVELOPMENT OF LEARNING VIDEO WITH OPEN ENDED APPROACH TO IMPROVE ABILITY MATHEMATICAL REASONING AND CRITICAL THINKING STUDENTS OF HIGH SCHOOL OF HIGH SCHOOL OF MUSLIMIN MEDAN IN MEDAN

2021 ◽  
Vol 14 (1) ◽  
pp. 75-79
Author(s):  
Mia Yolanda Siregar ◽  
◽  
Hasratuddin Siregar ◽  
Hermawan Syahputra
Keyword(s):  
High School ◽  
Critical Thinking ◽  
Mathematical Reasoning ◽  
Thinking Skills ◽  
Critical Thinking Skills ◽  
Development Model ◽  
Average Value ◽  
Reasoning Abilities ◽  
Second Stage ◽  
Two Stages

This research was conducted in two stages, namely the first stage of developing learning videos with the Open Ended approach using the ADDIE development model, and the second stage testing the learning videos with the Open Ended approach which was developed in grades VIII-1 and VIII-2 SMP Ikhwanul Muslimin Medan. From the results of the first and second trials, it was obtained: 1) In the first and second trials there was an increase in the average value of students' mathematical reasoning abilities of 14.64; 2) In the first and second trials there was an increase in the average value of students' mathematical critical thinking skills of 7.29; 3) Learning videos with an Open Ended approach to improve mathematical reasoning and critical thinking skills have been effective to use;

Altered Fine Structure of B Lymphocytes Correlated with Defective Terminal Differentiation

1973 ◽  
Vol 31 ◽  
pp. 386-387
Author(s):  
Dale E. Bockman ◽  
L. Y. Frank Wu ◽  
Alexander R. Lawton ◽  
Max D. Cooper
Keyword(s):  
Immune Deficiency ◽  
B Lymphocytes ◽  
Plasma Cells ◽  
Present Report ◽  
Specific Antigen ◽  
Terminal Differentiation ◽  
Second Stage ◽  
Two Stages ◽  
Deficiency Diseases ◽  
Cell Line Generation

B-lymphocytes normally synthesize small amounts of immunoglobulin, some of which is incorporated into the cell membrane where it serves as receptor of antigen. These cells, on contact with specific antigen, proliferate and differentiate to plasma cells which synthesize and secrete large quantities of immunoglobulin. The two stages of differentiation of this cell line (generation of B-lymphocytes and antigen-driven maturation to plasma cells) are clearly separable during ontogeny and in some immune deficiency diseases. The present report describes morphologic aberrations of B-lymphocytes in two diseases in which second stage differentiation is defective.

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