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Journal articles on the topic 'Numerical Ages'

Author: Grafiati

Published: 4 June 2021

Last updated: 1 February 2022

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1

Geyh, Mebus A. "The handling of numerical ages and their random uncertainties." E&G Quaternary Science Journal 57, no. 1/2 (August 1, 2008): 239–52. http://dx.doi.org/10.3285/eg.57.1-2.10.

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Abstract. The correct handling of numerical ages and their standard deviations and a proper introduction to error propagation or propagation of uncertainty and statistical evaluation are important to avoid misleading chronological conclusions and statements even though based on properly determined and reliable numerical dates. The conclusions may also be erroneous if dates were taken from databases without sufficient background information on the origin of the dated material and the applied analytical techniques. This paper is an introduction into the field of mathematical handling and testing

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Osborn, Gerald, Daniel McCarthy, Aline LaBrie, and Randall Burke. "Lichenometric Dating: Science or Pseudo-Science?" Quaternary Research 83, no. 1 (January 2015): 1–12. http://dx.doi.org/10.1016/j.yqres.2014.09.006.

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AbstractThe popular technique of estimating ages of deposits from sizes of lichens continues despite valid criticism, and without agreement on range of utility, treatment of error, and methods of measurement, sampling, and data handling. A major source of error is the assumption that the largest lichen(s) colonized soon after deposition and will survive indefinitely. Recent studies on lichen mortality suggest that this assumption is untenable. Meanwhile, the use of “growth curves” constructed from independently dated substrates is problematic for many reasons, but this has not prevented the pu

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3

Siegler, Robert S., and John E. Opfer. "The Development of Numerical Estimation." Psychological Science 14, no. 3 (May 2003): 237–50. http://dx.doi.org/10.1111/1467-9280.02438.

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We examined children's and adults' numerical estimation and the representations that gave rise to their estimates. The results were inconsistent with two prominent models of numerical representation: the logarithmic-ruler model, which proposes that people of all ages possess a single, logarithmically spaced representation of numbers, and the accumulator model, which proposes that people of all ages represent numbers as linearly increasing magnitudes with scalar variability. Instead, the data indicated that individual children possess multiple numerical representations; that with increasing age

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4

Liu, Longlong, Zhaosheng Zhang, Zehua Huangfu, and Dahai Huang. "Numerical analysis of concrete temperature stress at different loading ages." Journal of Physics: Conference Series 1732 (January 2021): 012107. http://dx.doi.org/10.1088/1742-6596/1732/1/012107.

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5

Legendre, Serge, and Bernadette Bachelet. "The numerical ages: A new method of datation applied to Paleogene mammalian localities from Southern France." Newsletters on Stratigraphy 29, no. 3 (November 19, 1993): 137–58. http://dx.doi.org/10.1127/nos/29/1993/137.

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6

Ali. "NUMERICAL PREDICTION MODEL FOR TEMPERATURE DISTRIBUTIONS IN CONCRETE AT EARLY AGES." American Journal of Engineering and Applied Sciences 5, no. 4 (April 1, 2012): 282–90. http://dx.doi.org/10.3844/ajeassp.2012.282.290.

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Ali. "NUMERICAL PREDICTION MODEL FOR TEMPERATURE DISTRIBUTIONS IN CONCRETE AT EARLY AGES." American Journal of Engineering and Applied Sciences 7, no. 2 (February 1, 2014): 255–65. http://dx.doi.org/10.3844/ajeassp.2014.255.265.

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8

Odin, G. S. "Concerning the numerical ages proposed for the Jurassic and Cretaceous geochronology." Geological Society, London, Memoirs 10, no. 1 (1985): 196–98. http://dx.doi.org/10.1144/gsl.mem.1985.010.01.16.

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9

van Breugel, K. "Numerical modelling of volume changes at early ages - Potential, pitfalls and challenges." Materials and Structures 34, no. 239 (April 27, 2001): 293–301. http://dx.doi.org/10.1617/13759.

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10

Jin, Nanguo, Ye Tian, and Xianyu Jin. "Numerical simulation of fracture and damage behaviour of concrete at different ages." Computers and Concrete 4, no. 3 (June 25, 2007): 221–41. http://dx.doi.org/10.12989/cac.2007.4.3.221.

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van Breugel, K. "Numerical modelling of volume changes at early ages-Potential, pitfalls and challenges." Materials and Structures 34, no. 5 (June 2001): 293–301. http://dx.doi.org/10.1007/bf02482209.

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12

Nyland, Kelsey E., Frederick E. Nelson, and Paula M. Figueiredo. "Cosmogenic 10Be and 36Cl geochronology of cryoplanation terraces in the Alaskan Yukon-Tanana Upland." Quaternary Research 97 (May 14, 2020): 157–66. http://dx.doi.org/10.1017/qua.2020.25.

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ABSTRACTCryoplanation terraces are prominent but enigmatic landforms found in present and past periglacial environments. Geomorphologists have debated for more than a century over processes involved in the formation of these elevated, step-like, bedrock features. Presented here are the first numerical surface exposure ages and scarp retreat rates from cryoplanation terraces in the Yukon-Tanana Upland (YTU) in Alaska, part of unglaciated eastern Beringia, obtained from terrestrial cosmogenic nuclides (TCN) in surface boulders. Ages comprise six 10Be TCN ages from two terrace treads near Eagle S

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Zharov, V. E. "I.I. Smul’skii. New astronomical theory of the ice ages." Вестник Российской академии наук 89, no. 8 (August 13, 2019): 878–79. http://dx.doi.org/10.31857/s0869-5873898878-879.

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Riga: Lap Lambert Academic Publishing, 2018. 132 Р. In this book, a new approach to the astronomical theory of climate change is considered, and problems of the orbital and rotational motion of the Earth are solved using the numerical method. The author of the monograph investigated the evolution of the earth’s axis and obtained the periods of its oscillations coinciding with observed oscillations. Calculations that covered 100,000 years showed a significant oscillation of the earth’s axis, which has led to fluctuations in insolation that can explain the changes in the paleoclimate.&#x0D

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14

Buczek, Alexandra J., Austin J. W. Hendy, Melanie J. Hopkins, and Jocelyn A. Sessa. "On the reconciliation of biostratigraphy and strontium isotope stratigraphy of three southern Californian Plio-Pleistocene formations." GSA Bulletin 133, no. 1-2 (May 6, 2020): 100–114. http://dx.doi.org/10.1130/b35488.1.

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Abstract The San Diego Formation, Pico Formation, Careaga Sandstone, and Foxen Mudstone of southern California are thought to be late Pliocene to early Pleistocene; however, numerical ages have not been determined. Following assessment of diagenetic alteration via multiple methods including scanning electron microscopy (SEM), X-ray diffraction (XRD), and minor elemental concentrations, we attempted to use strontium isotope stratigraphy to assign numerical ages. Using aragonitic fossils, we obtained ages of 2.0–1.85 Ma for the Careaga Sandstone and 2.0–1.75 Ma for the uppermost Foxen Mudstone,

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Gadotti, Dimitri A., and Ronaldo E. de Souza. "On the Lengths, Colours and Ages of Bars." Proceedings of the International Astronomical Union 2, S235 (August 2006): 98. http://dx.doi.org/10.1017/s1743921306005333.

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AbstractIn an effort to obtain further observational evidences for secular evolution processes in galaxies, as well as observational constraints to current theoretical models of secular evolution, we have used BVRI and Ks images of a sample of 18 barred galaxies to measure the lengths and colours of bars, create colour maps and estimate global colour gradients. In addition, applying a method we developed in a previous article, we could distinguish for 7 galaxies in our sample those whose bars have been recently formed from the ones with already evolved bars. We estimated an average difference

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16

Ren, Zheng, Lian Zhen Xiao, and Wen Chong Shi. "Experimental Study and Numerical Analysis on Chloride Diffusion Coefficient of Concrete with Various Water-Cement Ratios." Key Engineering Materials 726 (January 2017): 547–52. http://dx.doi.org/10.4028/www.scientific.net/kem.726.547.

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A rapid chloride ion diffusion coefficient measurement (RCM) was used in this study. The influence of water-cement ratios of 0.30, 0.35 and 0.40 at various ages (3, 7, 14, 28 and 56 days) on chloride ion diffusion coefficient of the concretes and pastes was studied and analyzed. The results show that, with the increase of curing ages, the chloride ion diffusion coefficient of different water-cement ratio of each specimen is decreased. In the early age, the chloride ion diffusion coefficient of the paste with the water-cement ratio of 0.40 is 2~3 times of the paste with water-cement ratio of 0.

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Luijendijk, Elco. "Beo v1.0: numerical model of heat flow and low-temperature thermochronology in hydrothermal systems." Geoscientific Model Development 12, no. 9 (September 20, 2019): 4061–73. http://dx.doi.org/10.5194/gmd-12-4061-2019.

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Abstract. Low-temperature thermochronology can provide records of the thermal history of the upper crust and can be a valuable tool to quantify the history of hydrothermal systems. However, existing model codes of heat flow around hydrothermal systems do not include low-temperature thermochronometer age predictions. Here I present a new model code that simulates thermal history around hydrothermal systems on geological timescales. The modelled thermal histories are used to calculate apatite (U–Th)∕He (AHe) ages, which is a thermochronometer that is sensitive to temperatures up to 70 ∘C. The mo

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18

Colman, Steven M., Kenneth L. Pierce, and Peter W. Birkeland. "Suggested Terminology for Quaternary Dating Methods." Quaternary Research 28, no. 2 (September 1987): 314–19. http://dx.doi.org/10.1016/0033-5894(87)90070-6.

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AbstractClassification of Quaternary dating methods should be based on the level of quantitative information and the degree of confidence contained in the age estimates produced by the dating methods. We recommend the use of the terms numerical-age, calibrated-age, relative-age, and correlated-age to describe these levels. We also classify dating methods by type into sideral, isotopic, radiogenic, chemical and biological, geomorphic, and correlation methods. The use of “absolute” is inappropriate for most dating methods, and should be replaced by “numerical.” The use of “date” should be minimi

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Park, Ki-Bong, Han-Seung Lee, and Xiao-Yong Wang. "Prediction of Time-Dependent Chloride Diffusion Coefficients for Slag-Blended Concrete." Advances in Materials Science and Engineering 2017 (2017): 1–10. http://dx.doi.org/10.1155/2017/1901459.

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The chloride diffusion coefficient is considered to be a key factor for evaluating the service life of ground-granulated blast-furnace slag (GGBS) blended concrete. The chloride diffusion coefficient relates to both the concrete mixing proportions and curing ages. Due to the continuous hydration of the binders, the capillary porosity of the concrete decreases and the chloride diffusion coefficient also decreases over time. To date, the dependence of chloride diffusivity on the binder hydration and curing ages of slag-blended concrete has not been considered in detail. To fill this gap, this st

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20

Fabel, Derek, David Fink, Ola Fredin, Jon Harbor, Magnus Land, and Arjen P. Stroeven. "Exposure ages from relict lateral moraines overridden by the Fennoscandian ice sheet." Quaternary Research 65, no. 1 (January 2006): 136–46. http://dx.doi.org/10.1016/j.yqres.2005.06.006.

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AbstractLateral moraines constructed along west to east sloping outlet glaciers from mountain centred, pre-last glacial maximum (LGM) ice fields of limited extent remain largely preserved in the northern Swedish landscape despite overriding by continental ice sheets, most recently during the last glacial. From field evidence, including geomorphological relationships and a detailed weathering profile including a buried soil, we have identified seven such lateral moraines that were overridden by the expansion and growth of the Fennoscandian ice sheet. Cosmogenic 10Be and 26Al exposure ages of 19

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21

Claoué-Long, J. C., P. J. Jones, J. Roberts, and S. Maxwell. "The numerical age of the Devonian-Carboniferous boundary." Geological Magazine 129, no. 3 (May 1992): 281–91. http://dx.doi.org/10.1017/s0016756800019221.

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AbstractThe SHRIMP ion microprobe has been used to date zircons in a 1 cm thick bentonite located in the Hasselbachtal auxiliary global stratotype section through the Devonian-Carboniferous boundary in Germany, and a tuff located at a similar biostratigraphic level in Australia. Multiple replicate analyses have yielded indistinguishable ages, and indicate 353.2±4.0 Ma (2σ) as the age of the boundary. Obtaining an age for the boundary in the German reference section depended on the ability of SHRIMP to date a small sample and to target small areas of structurally complex zircons. Future refinem

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22

Lena, Luis, Rafael López-Martínez, Marina Lescano, Beatriz Aguire-Urreta, Andrea Concheyro, Verónica Vennari, Maximiliano Naipauer, et al. "High-precision U–Pb ages in the early Tithonian to early Berriasian and implications for the numerical age of the Jurassic–Cretaceous boundary." Solid Earth 10, no. 1 (January 8, 2019): 1–14. http://dx.doi.org/10.5194/se-10-1-2019.

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Abstract. The numerical age of the Jurassic–Cretaceous boundary has been controversial and difficult to determine. In this study, we present high-precision U–Pb geochronological data around the Jurassic–Cretaceous boundary in two distinct sections from different sedimentary basins: the Las Loicas, Neuquén Basin, Argentina, and the Mazatepec, Sierra Madre Oriental, Mexico. These two sections contain primary and secondary fossiliferous markers for the boundary as well as interbedded volcanic ash horizons, allowing researchers to obtain new radioisotopic dates in the late Tithonian and early Berr

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23

AGUIRRE-URRETA, BEATRIZ, MARINA LESCANO, MARK D. SCHMITZ, MAISA TUNIK, ANDREA CONCHEYRO, PETER F. RAWSON, and VICTOR A. RAMOS. "Filling the gap: new precise Early Cretaceous radioisotopic ages from the Andes." Geological Magazine 152, no. 3 (January 26, 2015): 557–64. http://dx.doi.org/10.1017/s001675681400082x.

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AbstractTwo tuffs in the Lower Cretaceous Agrio Formation, Neuquén Basin, provided U–Pb zircon radioisotopic ages of 129.09±0.16 Ma and 127.42±0.15 Ma. Both horizons are well constrained biostratigraphically by ammonites and nannofossils and can be correlated with the ‘standard’ sequence of the Mediterranean Province. The lower horizon is very close to the base of the Upper Hauterivian and the upper horizon to the Hauterivian/Barremian boundary, indicating that the former lies atc. 129.5 Ma and the latter atc. 127 Ma. These new radioisotopic ages fill a gap of over 8 million years in the numer

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Lacarriere, Laurie, Alain Sellier, Pierre Souyris, Batian Kolani, and Ponleu Chhun. "Numerical prediction of cracking risk of reinforced concrete structures at early age." RILEM Technical Letters 5 (September 24, 2020): 41–55. http://dx.doi.org/10.21809/rilemtechlett.2020.106.

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The paper presents a summary of the work concerning the prediction of cracking risk in reinforced concrete structures at early age that has been carried out by our team at the LMDC laboratory during the last ten years. It focuses on the principles that must be taken into account in numerical simulations (evolution of characteristics, behaviour law, numerical implementation, effect of reinforcement, etc.) in order to be able to predict the cracking pattern caused in structures by the thermal loading induced by hydration at early ages

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Kasuya, Masao. "Fission-Track Ages of Tuff Layers Related to the Pliocene-Pleistocene Boundary on the Boso Peninsula, Japan." Quaternary Research 33, no. 1 (January 1990): 86–93. http://dx.doi.org/10.1016/0033-5894(90)90086-z.

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AbstractFission-track ages of zircon crystals from four tuff layers in the late Cenozoic sediment sequence of the Boso Peninsula,.Japan, are 1.6 ± 0.2 myr (the Kurotaki Formation), 5.5 ± 0.6 and 5.2 ± 0.5 myr (the uppermost part of the Amatsu Formation), and 11.5 ± 0.8 myr (the middle part of the Amatsu Formation). These ages provide numerical age constraints on magneto-biostratigraphy. The normal polarity interval in the lower part of the Kiwada Formation corresponds to the Olduvai polarity subzone. The boundary between the Pliocene and Pleistocene lies slightly above the Olduvai polarity sub

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Cheung, Pierina, and Mathieu Le Corre. "Parallel individuation supports numerical comparisons in preschoolers." Journal of Numerical Cognition 4, no. 2 (September 7, 2018): 380–409. http://dx.doi.org/10.5964/jnc.v4i2.110.

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While the approximate number system (ANS) has been shown to represent relations between numerosities starting in infancy, little is known about whether parallel individuation – a system dedicated to representing objects in small collections – can also be used to represent numerical relations between collections. To test this, we asked preschoolers between the ages of 2 ½ and 4 ½ to compare two arrays of figures that either included exclusively small numerosities (< 4) or exclusively large numerosities (> 4). The ratios of the comparisons were the same in both small and large numerosity c

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Gómez-Velázquez, Fabiola R., Andrés A. González-Garrido, Ricardo A. Salido-Ruiz, Sulema Torres-Ramos, Aurora Espinoza-Valdez, Israel Román-Godínez, and Erwin R. Villuendas-González. "Numerical Comparisons and Sex-Related Brain Connectivity." International Journal of Psychological Studies 13, no. 2 (May 20, 2021): 62. http://dx.doi.org/10.5539/ijps.v13n2p62.

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Despite the recent literature on sex-related anatomic, maturational and functional brain differences, the study of significant individual developments in math learning and achievement has scarcely approached this perspective. We aimed to compare the influence of sex in functional brain connectivity and behavioral measures in a numerical comparison task. Therefore, a group of school children with ages from 8 to 11 years old was evaluated during a number comparison task. Even though the behavioral performance was similar across the sexes, males distinctly showed a significant correlation between

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Francis, Julie E., Lawrence L. Loendorf, and Ronald I. Dorn. "AMS Radiocarbon and Cation-Ratio Dating of Rock Art in the Bighorn Basin of Wyoming and Montana." American Antiquity 58, no. 4 (October 1993): 711–37. http://dx.doi.org/10.2307/282204.

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Samples of organic matter and rock varnish from seven rock-art sites in the Bighorn Basin of Wyoming and Montana were collected for dating purposes. Petroglyphs sampled include Dinwoody-style figures, shield-bearing warriors, and other well-known Plains rock-art motifs. Accelerator mass spectrometry (AMS) dating of 10 petroglyphs yielded dates from the Early Archaic to the Protohistoric periods. A strong numerical relation between varnish leaching and time was found for petroglyphs older than 1,000 years, permitting the derivation of a cation-leaching curve (CLC) and calibrated cation-ratio (C

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29

Schweinsberg, Avriel D., Jason P. Briner, Joseph M. Licciardi, Ralph R. Shroba, and Eric M. Leonard. "Cosmogenic 10Be exposure dating of Bull Lake and Pinedale moraine sequences in the upper Arkansas River valley, Colorado Rocky Mountains, USA." Quaternary Research 97 (April 27, 2020): 125–39. http://dx.doi.org/10.1017/qua.2020.21.

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AbstractMany formerly glaciated valleys in the western United States preserve detailed glacial features that span the penultimate glaciation through the last deglaciation; however, numerical age control is limited in many of these systems. We report 35 new cosmogenic 10Be surface exposure ages of moraine boulders in the Sawatch Range, Colorado. Eight ages suggest Bull Lake moraines in Lake Creek (range: 132–120 ka, n = 4) and Clear Creek (range: 187–133 ka, n = 4) valleys may correlate with Marine Isotope Stage 6. In Lake Creek valley, 22 10Be ages from Pinedale end moraines average 20.6 ± 0.6

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Yang, Zixuan, Bing-Qing Deng, and Lian Shen. "Direct numerical simulation of wind turbulence over breaking waves." Journal of Fluid Mechanics 850 (July 4, 2018): 120–55. http://dx.doi.org/10.1017/jfm.2018.466.

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We study wind turbulence over breaking waves based on direct numerical simulation (DNS) of two-fluid flows. In the DNS, the air and water are simulated as a coherent system, with the interface captured using the coupled level-set and volume-of-fluid method. Because the wave breaking is an unsteady process, we use ensemble averaging over 100 runs to define turbulence statistics. We focus on analysing the turbulence statistics of the airflow over breaking waves. The effects of wave age and wave steepness are investigated. It is found that before wave breaking, the turbulence statistics are large

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ZHANG, Xiaofei, Xin ZHANG, Tao YAN, Yu HUANG, Qian LIU, and Xiaoping WANG. "Experimental analysis and numerical calculation on equivalent strength of induced joints of different ages and weakening degrees." Journal of the Ceramic Society of Japan 127, no. 9 (September 1, 2019): 642–50. http://dx.doi.org/10.2109/jcersj2.18196.

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BUKRY, DAVID. "Numerical ages of Cenozoic biostratigraphic datum levels: Results of South Atlantic Leg 73 drilling: Discussion and reply." Geological Society of America Bulletin 96, no. 6 (1985): 813. http://dx.doi.org/10.1130/0016-7606(1985)96<813:naocbd>2.0.co;2.

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HSÜ, KENNETH J. "Numerical ages of Cenozoic biostratigraphic datum levels: Results of South Atlantic Leg 73 drilling: Discussion and reply." Geological Society of America Bulletin 96, no. 6 (1985): 814. http://dx.doi.org/10.1130/0016-7606(1985)96<814:naocbd>2.0.co;2.

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COMPSTON, W., M. S. SAMBRIDGE, R. F. REINFRANK, M. MOCZYDEOWSKA, G. VIDAL, and S. CLAESSON. "Numerical ages of volcanic rocks and the earliest fauna1 zone within the Late Precambrian of east Poland." Journal of the Geological Society 152, no. 4 (July 1995): 599–611. http://dx.doi.org/10.1144/gsjgs.152.4.0599.

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Balco, Greg, John O. H. Stone, and Joseph A. Mason. "Numerical ages for Plio-Pleistocene glacial sediment sequences by 26Al/10Be dating of quartz in buried paleosols." Earth and Planetary Science Letters 232, no. 1-2 (March 2005): 179–91. http://dx.doi.org/10.1016/j.epsl.2004.12.013.

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McDougall, I., and R. T. Watkins. "Potassium–argon ages of volcanic rocks from northeast of Lake Turkana, northern Kenya." Geological Magazine 125, no. 1 (January 1988): 15–23. http://dx.doi.org/10.1017/s001675680000933x.

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AbstractThe Asille Group, a 1500 m succession comprising dominantly basaltic lavas but with interbedded sediments and silicic volcanics, lies unconformably upon metamorphosed basement northeast of Lake Turkana. Concordant K–Ar ages on alkali feldspars from pantelleritic units in the succession show that the Langaria Formation erupted 26.9±0.3 Ma ago in late Oligocene time, that Gum Dura Formation volcanism occurred at 15.8±0.2 Ma (early Miocene), and that there was widespread middle Miocene silicic volcanism at 13.0±0.3 Ma. Younger basaltic volcanism producing the flood lavas of the Gombe Grou

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Compston, W. "Interpretations of SHRIMP and isotope dilution zircon ages for the geological time-scale: I. The early Ordovician and late Cambrian." Mineralogical Magazine 64, no. 1 (February 2000): 43–57. http://dx.doi.org/10.1180/002646100549120.

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AbstractIon probe data for zircons from tuffs within the Llfynant flags (Arenig) and the Serw Formation (lower Llanvirn) of north Wales have been revised using better statistical methods for separating detrital ages, making allowance for recently-found variability in radiogenic 206Pb/238U in the reference zircon SL13, and testing the sensitivity of the ages to the secondary ion discrimination slope. The revised ages are options of 469.2 ± 2.1 (σ) or 472.9 ± 2.9 Ma for the Llfynant flags dependent on mixture modelling, and 465.3 ± 1.4 Ma for the Serw Formation. All ages are within error of prev

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Yang, Di, and Lian Shen. "Direct numerical simulation of scalar transport in turbulent flows over progressive surface waves." Journal of Fluid Mechanics 819 (April 18, 2017): 58–103. http://dx.doi.org/10.1017/jfm.2017.164.

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The transport of passive scalars in turbulent flows over progressive water waves is studied using direct numerical simulation. A combined pseudo-spectral and finite-difference scheme on a wave-surface-fitted grid is used to simulate the flow and scalar fields above the wave surface. Three representative wave ages (i.e. wave-to-wind speed ratios) are considered, corresponding to slow, intermediate and fast wind-waves, respectively. For each wave condition, four Schmidt numbers are considered for the scalar transport. The presence of progressive surface waves is found to induce significant wave-

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Kobayashi, Lindsay C., and Justin Michael Feldman. "Employment trajectories in midlife and cognitive performance in later life: longitudinal study of older American men and women." Journal of Epidemiology and Community Health 73, no. 3 (November 23, 2018): 232–38. http://dx.doi.org/10.1136/jech-2018-211153.

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BackgroundAlthough being employed during midlife is positively associated with cognitive function in later life, little is known with respect to cumulative trajectories or durations of time spent in different kinds of work.MethodsWe investigated the relationships between employment trajectory from ages 31 years to 50 years and cognitive skills at ages 50–78 years among 2521 adults in the US Panel Study of Income Dynamics from 1968 to 2016. Sequence analysis was used to identify prototypical employment trajectories, capturing employment status and high versus lower job skill level at each year

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Rahimzadeh, Neda, Tobias Sprafke, Christine Thiel, Birgit Terhorst, and Manfred Frechen. "A comparison of polymineral and K-feldspar post-infrared infrared stimulated luminescence ages of loess from Franconia, southern Germany." E&G Quaternary Science Journal 70, no. 1 (February 8, 2021): 53–71. http://dx.doi.org/10.5194/egqsj-70-53-2021.

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Abstract. Loess-paleosol sequences (LPSs) are essential records for reconstructing Quaternary paleoenvironments. No previous study has provided numerical chronologies of loess in Lower Franconia, southern Germany; their chronostratigraphic assumptions have relied mainly on German (pedo)stratigraphic schemes. In this study, we provide for the first time a chronology for LPSs in Lower Franconia based on optically stimulated luminescence (OSL) dating using quartz and a comparison of K-feldspar (63–100 µm) and the polymineral fraction (4–11 µm). Our results show that all obtained ages are in strat

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Chen, Wei, Yuan Li, Peiliang Shen, and Zhonghe Shui. "Microstructural Development of Hydrating Portland Cement Paste at Early Ages Investigated with Non-destructive Methods and Numerical Simulation." Journal of Nondestructive Evaluation 32, no. 3 (March 2, 2013): 228–37. http://dx.doi.org/10.1007/s10921-013-0175-y.

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Rinat, Yair, Ari Matmon, Maurice Arnold, Georges Aumaître, Didier Bourlès, Karim Keddadouche, Naomi Porat, Efrat Morin, and Robert C. Finkel. "Holocene rockfalls in the southern Negev Desert, Israel and their relation to Dead Sea fault earthquakes." Quaternary Research 81, no. 2 (March 2014): 260–73. http://dx.doi.org/10.1016/j.yqres.2013.12.008.

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AbstractRockfall ages in tectonically active regions provide information regarding frequency and magnitude of earthquakes. In the hyper-arid environment of the Dead Sea fault (DSF), southern Israel, rockfalls are most probably triggered by earthquakes. We dated rockfalls along the western margin of the DSF using terrestrial cosmogenic nuclides (TCN). At each rockfall site, samples were collected from simultaneously exposed conjugate boulders and cliff surfaces. Such conjugate samples initially had identical pre-fall (“inherited”) TCN concentrations. After boulder detachment, these surfaces wer

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Bremigan, Elizabeth George. "Activities for Students: Designing the Dynamic Domino Race." Mathematics Teacher 95, no. 7 (October 2002): 502–8. http://dx.doi.org/10.5951/mt.95.7.0502.

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Students of all ages are enthusiastic about the Olympic Games. Many mathematics teachers use this context as an opportunity for students to examine numerical data while they display and discuss the results of different events and the success of various countries during the Olympic Games. These discussions allow teachers to address several aspects of the Data Analysis and Probability Standard from Principles and Standards for School Mathematics (NCTM 2000).

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Bremigan, Elizabeth George. "Activities for Students: Designing the Dynamic Domino Race." Mathematics Teacher 95, no. 7 (October 2002): 502–8. http://dx.doi.org/10.5951/mt.95.7.0502.

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Students of all ages are enthusiastic about the Olympic Games. Many mathematics teachers use this context as an opportunity for students to examine numerical data while they display and discuss the results of different events and the success of various countries during the Olympic Games. These discussions allow teachers to address several aspects of the Data Analysis and Probability Standard from Principles and Standards for School Mathematics (NCTM 2000).

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Clauer, Norbert. "How Can Technical Aspects Help Improving K-Ar Isotopic Data of Illite-Rich Clay Materials into Meaningful Ages? The Case of the Dominique Peter Uranium Deposit (Saskatchewan, Canada)." Geosciences 10, no. 8 (July 27, 2020): 285. http://dx.doi.org/10.3390/geosciences10080285.

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Previously published K-Ar dating results of <2 μm illite separates from uranium-hosting and associated barren rocks from Dominique Peter district of the Carswell circular structure in the Athabasca Basin (Canada) were considered to trace four distinct tectonic-thermal events at 1447 ± 45, 1282 ± 40 and 1184 ± 15 (all errors at ± 2 Ma, with a younger, less constrained episode at ~900 Ma. Recent analyses of K-Ar ages of additional <0.2 μm illite fractions from a few initial samples demonstrate that the intermediate ages at ~1280 and ~1185 Ma result, in fact, from mixing of two generations

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Steuber, Thomas, and Malte Schlüter. "Strontium-isotope stratigraphy of Upper Cretaceous rudist bivalves: Biozones, evolutionary patterns and sea-level change calibrated to numerical ages." Earth-Science Reviews 114, no. 1-2 (August 2012): 42–60. http://dx.doi.org/10.1016/j.earscirev.2012.04.004.

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Wyrzykowski, Mateusz, Julien Sanahuja, Laurent Charpin, Markus Königsberger, Christian Hellmich, Bernhard Pichler, Luca Valentini, et al. "Numerical benchmark campaign of COST Action TU1404 – microstructural modelling." RILEM Technical Letters 2 (December 30, 2017): 99–107. http://dx.doi.org/10.21809/rilemtechlett.2017.44.

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This paper presents the results of the numerical benchmark campaign on modelling of hydration and microstructure development of cementitious materials. This numerical benchmark was performed in the scope of COST Action TU1404 “Towards the next generation of standards for service life of cement-based materials and structures”. Seven modelling groups took part in the campaign applying different models for prediction of mechanical properties (elastic moduli or compressive strength) in cement pastes and mortars. The simulations were based on published experimental data. The experimental data (both

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Nordström, B., J. Andersen, and J. Holmberg. "Evolution of the Galactic Disk from a Local Sample." Proceedings of the International Astronomical Union 2, S235 (August 2006): 126. http://dx.doi.org/10.1017/s1743921306005588.

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AbstractThe Geneva-Copenhagen Survey (Nordström et al., 2004) gives ages, metallicities, velocities, and Galactic orbits for a complete, magnitude-limited sample of 14,000 F and G dwarfs. We have verified the calibrations used in the GCS, improved those of Teff, [Fe/H], distance, and age from uvby β, and checked the effect on the resulting Galactic relations by end- to-end numerical simulations. All the main results of the GCS remain unchanged.

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Ali, Wondwosen, and Girum Urgessa. "Computational Model for Internal Relative Humidity Distributions in Concrete." Journal of Computational Engineering 2014 (March 9, 2014): 1–7. http://dx.doi.org/10.1155/2014/539850.

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A computational model is developed for predicting nonuniform internal relative humidity distribution in concrete. Internal relative humidity distribution is known to have a direct effect on the nonuniform drying shrinkage strains. These nonuniform drying shrinkage strains result in the buildup of internal stresses, which may lead to cracking of concrete. This may be particularly true at early ages of concrete since the concrete is relatively weak while the difference in internal relative humidity is probably high. The results obtained from this model can be used by structural and construction

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Colman, Steven M., and Kenneth L. Pierce. "Glacial Sequence Near McCall, Idaho: Weathering Rinds, Soil Development, Morphology, and Other Relative-Age Criteria." Quaternary Research 25, no. 1 (January 1986): 25–42. http://dx.doi.org/10.1016/0033-5894(86)90041-4.

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The sequence of glacial deposits near McCall, Idaho, previously assigned to the Pinedale and Bull Lake glaciations, contains deposits of four different ages. These ages are defined by multiple relative-age criteria, including weathering rinds, soil development, surface-rock weathering, morainal morphology, and loess stratigraphy. The thickness of weathering rinds on basaltic clasts is statistically representative and reproducible and can be used to estimate numerical ages. Following in order of decreasing relation to age are soil development, surface-rock weathering, and moraine morphology. Th

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