Papers in Physics最新文献

Detection and classification of rainfall in South America using satellite images and machine learning techniques 利用卫星图像和机器学习技术对南美洲降雨量进行检测和分类

IF 0.9

Papers in Physics Pub Date : 2023-12-22 DOI: 10.4279/pip.150006

Federico Andelsman, Sergio Masuelli, Francisco Tamarit

{"title":"Detection and classification of rainfall in South America using satellite images and machine learning techniques","authors":"Federico Andelsman, Sergio Masuelli, Francisco Tamarit","doi":"10.4279/pip.150006","DOIUrl":"https://doi.org/10.4279/pip.150006","url":null,"abstract":"The study of precipitation is one of the most intriguing areas in atmospheric sciences, with significant implications for our daily lives and climate change projections. This paper explores the estimation of rainfall trends in South American regions using convolutional neural networks (CNNs). The study focuses on the application of Cloud-Net, a CNN-based model with a format similar to an autoencoder, to obtain qualitative estimates of precipitation patterns. The employed loss functions, Categorical Cross Entropy and Categorical Focal Loss, address the challenges of classifying minority categories in unbalanced data. Regional analysis was conducted, identifying days with high rainfall intensity and the predominant intensities in 25 regions. The CNN model’s performance was compared with the XGBoost algorithm, showing excellent results for extreme rainfall categories and challenging intermediate categories. Furthermore, a comparison was made with Quantitative Precipitation Estimation (QPE) data and ground measurements from rain gauges. While the CNN model provided a valuable qualitative estimate of precipitation trends, achieving precise quantitative estimation would require an extensive data set of in-situ measurements. Overall, this research demonstrates the potential of CNNs for estimating rainfall trends and understanding precipitation patterns in South American regions. The findings offer valuable insights for further applications in meteorology and environmental studies.","PeriodicalId":19791,"journal":{"name":"Papers in Physics","volume":null,"pages":null},"PeriodicalIF":0.9,"publicationDate":"2023-12-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138945817","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Electric reduced transition probabilities of (^{186}text{W}) and (^{186}text{Os}) isobars through the interacting boson model-I 通过相互作用玻色子模型-I 实现的等（^{186}text{W}）和（^{186}text{Os}）等值线的电还原转换概率

IF 0.9

Papers in Physics Pub Date : 2023-12-08 DOI: 10.4279/pip.150005

A. Salam, I. Hossain, H. H. Kassim, Ahmed Saleh, A. H. H. Alghanmi, F. I. Sharrad, N. Aldahan

{"title":"Electric reduced transition probabilities of (^{186}text{W}) and (^{186}text{Os}) isobars through the interacting boson model-I","authors":"A. Salam, I. Hossain, H. H. Kassim, Ahmed Saleh, A. H. H. Alghanmi, F. I. Sharrad, N. Aldahan","doi":"10.4279/pip.150005","DOIUrl":"https://doi.org/10.4279/pip.150005","url":null,"abstract":"In this study, we applied the Interacting Boson Model (IBM-I) to compute the electric reduced transition probabilities B(E2)(downarrow) of even-even neutron rich (^{186}text{W}) and (^{186}text{Os}) isobars. The ratio (R_{4/2} = E(4_{1}^{+}) / E(2_{1}^{+})) has also been calculated for those isobars and the SU(3) symmetry for those isobars has been reported. (E(4_{1}^{+})) and (E(2_{1}^{+})) indicate the energy level of (4_{1}^{+}) and (2_{1}^{+}), respectively. We have described the strength of B(E2) in W.u. for (^{186}text{W}) and (^{186}text{Os}) isobars of some of the low-lying quadrupole collective states in contrast to obtainable measured data. The electric reduced transition probabilities B(E2)(downarrow) from yrast state gamma transition from (12_1^{+} rightarrow 10_1^{+}), (10_1^{+} rightarrow 8_1^{+}), (8_1^{+} rightarrow 6_1^{+}), (6_1^{+} rightarrow 4_1^{+}), (4_1^{+} rightarrow 2_1^{+}) and (2_1^{+} rightarrow 0_1^{+}) and other bands states and B(E2) ratio of (^{186}text{W}) and (^{186}text{Os}) isobars have been compared with obtainable measured data and other previous studies. Also calculated were the systematic strength of B(E2), intrinsic quadrupole moments, and deformation parameters of even-even (^{186}text{W}) and (^{186}text{Os}) isobars. The data from these calculations are in good matching with the obtainable measured data. The IBM-I model for the strength of B(E2) has been systematically deduced in SU(3) limit for a few yrasts states transitions in (^{186}text{W}) and (^{186}text{Os}) isobars.","PeriodicalId":19791,"journal":{"name":"Papers in Physics","volume":null,"pages":null},"PeriodicalIF":0.9,"publicationDate":"2023-12-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138587512","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Insights into vibrational and electronic properties of (6,6)-phenyl-C61-butyric acid methyl ester (PCBM) chemical bonding with (CuO)n clusters: a DFT study (6,6)-苯基- c61 -丁酸甲酯(PCBM)与(CuO)n簇化学键合的振动和电子性质:DFT研究

Papers in Physics Pub Date : 2023-10-19 DOI: 10.4279/pip.150004

Carlos Eduardo Martínez-Núñez, Y Delgado-Beleño, M Cortez-Valadez, O Rocha-Rocha, Ramón A B Alvarez, M Flores-Acosta

引用次数: 0

Study of hysteresis in the ferromagnetic random field 3-state clock model in two and three dimensional periodic lattices at zero temperature and in the presence of dilution and an absorbing state 零温度、稀释和吸收状态下二维和三维周期晶格中铁磁随机场三态时钟模型的磁滞研究

IF 0.9

Papers in Physics Pub Date : 2023-06-16 DOI: 10.4279/pip.150003

Elisheba Syiem, R. Kharwanlang

引用次数: 0

Changes in the surface irradiance during the total solar eclipse 2020 in Valcheta, Argentina 阿根廷瓦尔切塔2020年日全食期间地表辐照度的变化

IF 0.9

Papers in Physics Pub Date : 2023-04-04 DOI: 10.4279/pip.150002

P. F. Orte, E. Fernández Lajús, R. P. Di Sisto, E. Wolfram, Anabela Lusi, M. G. Nicora, R. D’Elia, Federico Verstraeten, S. Papandrea, Facundo Carmona

{"title":"Changes in the surface irradiance during the total solar eclipse 2020 in Valcheta, Argentina","authors":"P. F. Orte, E. Fernández Lajús, R. P. Di Sisto, E. Wolfram, Anabela Lusi, M. G. Nicora, R. D’Elia, Federico Verstraeten, S. Papandrea, Facundo Carmona","doi":"10.4279/pip.150002","DOIUrl":"https://doi.org/10.4279/pip.150002","url":null,"abstract":"On December 14, 2020, southern South America experienced a total solar eclipse close to the solar noon. The path of totality, about 90 km wide, extended over the continental region from the Chilean west coast to the Argentine east coast, passing through the provinces of Neuquén, Río Negro and the extreme south of Buenos Aires. In order to study the effects on the atmosphere produced by the total eclipse, the Servicio Meteorológico Nacional Argentino (SMN) and Instituto de Investigaciones Científicas y Técnicas para la Defensa (CITEDEF) carried out a surface radiometric monitoring campaign in Valcheta (40.69°S; 66.15°W), Río Negro, Argentina. In this work, we explore the global surface solar irradiance on a horizontal plane (GHI) with the main objective of quantifying the changes in this parameter for cloudy and clear sky atmospheric conditions, combining ground-based measurements and modeling. A solar limb-darkening function was successfully implemented in the calculation of the irradiance at the top of the atmosphere (TOA) during the eclipse. We estimated a significant GHI attenuation of 41 % between the first (C1) and last (C4) contacts of eclipse compared to similar atmospheric conditions without the total eclipse, which represent a daily reduction of 12 %. In terms of irradiation, a reduction of 3360.1 KJ/m2 was calculated.","PeriodicalId":19791,"journal":{"name":"Papers in Physics","volume":null,"pages":null},"PeriodicalIF":0.9,"publicationDate":"2023-04-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43907941","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

When you can’t count, sample! 当你不能数的时候，抽样!

IF 0.9

Papers in Physics Pub Date : 2023-02-11 DOI: 10.4279/pip.150001

Stefano Martiniani, Mathias Casiulis

引用次数: 1

Down to the root of vegetated soil: challenges and state-of-the-art 深入到植被土壤的根源：挑战和最新技术

IF 0.9

Papers in Physics Pub Date : 2022-11-30 DOI: 10.4279/pip.140014

Hongyang Cheng, F. Anselmucci, Xinyan Fan, Yijian Zeng, S. Luding, V. Magnanimo

{"title":"Down to the root of vegetated soil: challenges and state-of-the-art","authors":"Hongyang Cheng, F. Anselmucci, Xinyan Fan, Yijian Zeng, S. Luding, V. Magnanimo","doi":"10.4279/pip.140014","DOIUrl":"https://doi.org/10.4279/pip.140014","url":null,"abstract":"Vegetated soil plays an essential role in confronting climate change. It is the host material where inorganic carbon is stored and green infrastructures are built. The expected impacts of climate change, such as extreme wetting-drying cycles, pose an urgent need to understand the interplay between soil deformation, root growth, and water/solute uptake. The key to this challenge lies in the extension of unsaturated soil mechanics to incorporate bio-hydrological processes, such as root growth and water uptake. In this paper, we first provide an overview of the state-of-the-art knowledge of root-zone mechanics and bio-hydrology. We identify the main knowledge gaps and suggest an integrated, bottom-to-top approach to develop a multidisciplinary understanding of soil-water-root interaction. We demonstrate how emerging experimental and numerical methods can be used to study rooted soil under wetting--drying cycles. Although focused on the biophysical processes at root/soil particle scales, we discuss potential up-scaling from the root to the field scale and further research on remaining challenges, such as the microbial activities in vegetated soil.","PeriodicalId":19791,"journal":{"name":"Papers in Physics","volume":null,"pages":null},"PeriodicalIF":0.9,"publicationDate":"2022-11-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42285369","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Observation of atmospheric scintillation during the 2020 total eclipse in northern Patagonia 2020年巴塔哥尼亚北部日全食期间的大气闪烁观测

IF 0.9

Papers in Physics Pub Date : 2022-11-04 DOI: 10.4279/pip.140013

C. Schmiegelow, Martín Drechsler, Lautaro E. Filgueria, Nicolás A. Nuñez Barreto, Franco Meconi

引用次数: 0

Confined sheared flows of hard and soft granular materials: Some challenges in tribology and fault mechanics 软硬颗粒材料的受限剪切流：摩擦学和故障力学中的一些挑战

IF 0.9

Papers in Physics Pub Date : 2022-08-31 DOI: 10.4279/pip.140012

G. Mollon, A. Quacquarelli, Yinyin Zhang, N. Casas, O. Bouillanne, Alizée Madrignac, Kevin Daigne

引用次数: 0

Future challenges on focused fluid migration in sedimentary basins: insight from field data, laboratory experiments and numerical simulations 沉积盆地聚焦流体运移的未来挑战:来自现场数据、实验室实验和数值模拟的见解

IF 0.9

Papers in Physics Pub Date : 2022-07-22 DOI: 10.4279/pip.140011

V. Vidal, A. Gay

{"title":"Future challenges on focused fluid migration in sedimentary basins: insight from field data, laboratory experiments and numerical simulations","authors":"V. Vidal, A. Gay","doi":"10.4279/pip.140011","DOIUrl":"https://doi.org/10.4279/pip.140011","url":null,"abstract":"In a present context of sustainable energy and hazard mitigation, understanding fluid migration in sedimentary basins – large subsea provinces of fine saturated sands and clays – is a crucial challenge. Such migration leads to gas or liquid expulsion at the seafloor, whichmay be the signature of deep hydrocarbon reservoirs, or precursors to violent subsea fluid releases. If the former may orient future exploitation, the latter represent strong hazards for anthropic activities such as offshore production, CO$_2$ storage, transoceanic telecom fibers or deep-sea mining. However, at present, the dynamics of fluid migration in sedimentary layers, in particular the upper 500 m, still remains unknown in spite of its strong influence on fluid distribution at the seafloor. Understanding the mechanisms controlling fluid migration and release requires the combination of accurate field data, laboratory experiments and numerical simulations. Each technique shall lead to the understanding of the fluid structures, the mechanisms at stake, and deep insights into fundamental processes ranging from the grain scale to the kilometers-long natural pipes in the sedimentary layers.Here we review the present available techniques, advances and challenges still open for the geosciences, physics, and computer science communities.","PeriodicalId":19791,"journal":{"name":"Papers in Physics","volume":null,"pages":null},"PeriodicalIF":0.9,"publicationDate":"2022-07-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41303901","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 1