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Radiative capture of proton through the ^(14)N(p,γ)^(15)O reaction at low energy

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Chinese Physics C 2024年第4期48卷 183-192页

作者： B.F.Irgaziev Abdul Kabir Jameel-Un Nabi National University of Uzbekistan Tashkent 100174Uzbekistan Space and Astrophysics Research lab National Centre of GIS and Space ApplicationsDepartment of Space ScienceInstitute of Space TechnologyIslamabad 44000Pakistan University of Wah Quaid AvenueWah Cantt 47040PunjabPakistan

The CNO cycle is the main source of energy in stars more massive than our *** process defines the energy production,the duration of which can be used to determine the lifetime of massive *** cycle is an important tool for determining the age of globular *** proton capture via p+^(14)N→^(15)O+γ,at energies of astrophysical interest,is an important process in the CNO *** this project,we apply a potential model to describe both non-resonant and resonant reactions in the channels where radiative capture occurs through electric E1 *** employed the R-matrix method to describe the ongoing reactions via M1 resonant transitions,when it was not possible to correctly reproduce the experimental data using the potential *** partial components of the astrophysical S-factor are calculated for all possible electric and magnetic dipole transitions in ^(15)*** linear extrapolated S-factor at zero energy(S(0))agrees well with earlier reported values for all transition types considered in this *** on the value of the total astrophysical S-factor,depending on the collision energy,we calculate the nuclear reaction rates for p+^(14)N→^(15)O+γ.The computed rates agree well with the results reported in the NACRE II Collaboration and most recent existing measurements.

关键词： CNO cycle potential model R-matrix method cross-section astrophysical S-factor nuclear rates.

西南地区河成湖与火山湖土地利用对水质的多时空尺度影响差异

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湖泊科学 2024年

作者：刘捷刘睿左书林张静重庆师范大学地理与旅游学院重庆师范大学gis应用研究重庆市重点实验室

为探究不同时空尺度下不同湖泊类型土地利用对水质的影响差异，以四川省自贡市富顺西湖(河成湖)和云南省腾冲市青海湖(火山湖)为研究对象，提取6个空间尺度(50、60、70、80、90、100m湖岸带缓冲区)的景观格局指数，结合雨季(2022年7月)... 详细信息

为探究不同时空尺度下不同湖泊类型土地利用对水质的影响差异，以四川省自贡市富顺西湖(河成湖)和云南省腾冲市青海湖(火山湖)为研究对象，提取6个空间尺度(50、60、70、80、90、100m湖岸带缓冲区)的景观格局指数，结合雨季(2022年7月)和旱季(2023年4月)湖泊水质参数，采用冗余分析法定量探究不同时空尺度下土地利用对两类湖泊水质影响的差异性。结果表明：(1)富顺西湖与腾冲青海湖水质参数季节性差异显著，雨季水质优于旱季，两个湖泊水环境质量存在显著差异，腾冲青海湖水环境质量优于富顺西湖，腾冲青海湖符合地表水环境Ⅱ类、Ⅲ类水质标准，富顺西湖达到Ⅳ类、Ⅴ类水质标准。(2)富顺西湖在旱季和50～60 m湖岸带缓冲区土地利用参数对水质变量解释率最大，腾冲青海湖在雨季和60 m湖岸带缓冲区尺度下土地利用参数对水质变量解释率最大。(3)土地利用指数对两类湖泊水质的影响各不相同。富顺西湖流域内斑块密度、景观形状指数和聚合度指数与多数水质指标呈正相关，“源”景观聚集程度和破碎化程度高会加剧对水质的威胁。腾冲青海湖流域内林地面积占比和聚合度指数对水质具有正效应，能够改善水环境质量；斑块指数和景观形状指数值的增加会加剧斑块破碎化，导致水质恶化。本研究基于不同时空尺度对土地利用与两类湖泊水质关系的差异性进行深入探讨，指导不同类型湖泊的区域规划与管理，为湖泊环境质量评价及保护和制定针对性的湖泊缓冲带设置、生态修复等策略提供科学依据，进而促进湖泊水质安全和水资源可持续利用。

关键词：土地利用水质多尺度效应冗余分析西南地区湖泊

Transformer-Based Cloud Detection Method for High-Resolution Remote Sensing Imagery

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Computers, Materials & Continua 2024年第7期80卷 661-678页

作者： Haotang Tan Song Sun Tian Cheng Xiyuan Shu Key Laboratory of gis Application Research School of Geography and TourismChongqing Normal UniversityChongqing401331China College of Computer and Information Science Chongqing Normal UniversityChongqing401331China Department of Military Installations Army Logistics AcademyChongqing401331China

Cloud detection from satellite and drone imagery is crucial for applications such as weather forecasting and *** the limitations of conventional convolutional neural networks,we propose an innovative transformer-based *** method leverages transformers,which are adept at processing data sequences,to enhance cloud detection ***,we introduce a Cyclic Refinement Architecture that improves the resolution and quality of feature extraction,thereby aiding in the retention of critical details often lost during cloud *** extensive experimental validation shows that our approach significantly outperforms established models,excelling in high-resolution feature extraction and precise cloud *** integrating Positional Visual Transformers(PVT)with this architecture,our method advances high-resolution feature delineation and segmentation ***,our research offers a novel perspective for surmounting traditional challenges in cloud detection and contributes to the advancement of precise and dependable image analysis across various domains.

关键词： Cloud transformer image segmentation remotely sensed imagery pyramid vision transformer

基于SHAP的可解释机器学习的滑坡易发性评价模型

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成都理工大学学报(自然科学版) 2024年

作者：崔婷婷安雪莲孙德亮陈东升朱有晨重庆对外经贸学院数学与计算机学院重庆师范大学gis应用研究重庆市高校重点实验室

机器学习在构建滑坡易发性评价模型中因其训练复杂且预测结果难以解释而发展受限。本研究通过SHAP（SHapley Additive exPlanations）结合机器学习模型揭示各影响因子对滑坡发育的影响，增强模型可信度与可解释性。以三峡库区忠县为研... 详细信息

机器学习在构建滑坡易发性评价模型中因其训练复杂且预测结果难以解释而发展受限。本研究通过SHAP（SHapley Additive exPlanations）结合机器学习模型揭示各影响因子对滑坡发育的影响，增强模型可信度与可解释性。以三峡库区忠县为研究区，通过随机森林、XGBoost以及深度随机森林机器学习算法结合贝叶斯优化算法分别构建滑坡易发性评价模型；利用混淆矩阵及接受者操作特征曲线开展评价精度验证；基于四种分级方法得到滑坡易发性区划图；通过SHAP分析影响滑坡发育的主导因子。结果表明优化后的XGBoost模型AUC值（0.817），高于随机森林的AUC值（0.803）和深度随机森林的AUC值（0.806）；不同分级方式下的易发性区划图分布差异很大，其中基于相等间隔法和XGBoost模型的分级效果相对更好，极高-高易发区主要集中在研究区的东南部和东北部，特别是长江及其支流两岸。SHAP图揭示各主导因子不同特征值对滑坡发育有明显差异，高程和距河流距离是研究区滑坡发育的主要影响因子，对滑坡发育贡献显著。本研究的XGBoost模型具有较高的预测精度，模型可解释性强，为滑坡灾害的精准防治提供科学依据。

关键词： XGBoost 深度随机森林 SHAP 三峡库区滑坡易发性评价

An integrated spatial planning of the mountainous landscapes for ski sports in a case area at the eastern Türkiye

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Journal of Mountain Science 2024年第3期21卷 754-767页

作者： SATIR Onur TOSUN Busra COSKUN OZYOL Funda OZDEMIR Omer Faruk BERBEROGLU Suha Dept.of Landscape Architecture Van Yuzuncu Yil UniversityVan 65090Türkiye School of Physical Education&Sports Van Yuzuncu Yil UniversityVan 65090Türkiye Van Yuzuncu Yil University Dept.of Architecture&Urban Planning Van 65090Türkiye Dept.of Remote Sensing&gis Cukurova UniversityAdana 01330Türkiye

Mountainous regions have disadvantages in economic development because of harsh physical and climatic ***,winter tourism activities are one of the key components for supporting economic development in the *** a ski resort area supports direct and indirect employment in a region,and it stops immigration from mountainous regions to other *** research aimed to assess the potential ski areas using a multi criteria evaluation technique in the Van region which is located in the eastern part of Tü*** this context,snow cover duration,sun effect,slope,slope length,elevation,population density,distance from main roads and lake visibility were used as input factors in the decision making *** factor was standardized using a fuzzy technique based on existing well-known ski centers in Tü*** weight of inputs was defined by applying a survey to the professional *** most important factors were detected as transportation opportunities and snow covers whereas,the least important factors were elevation and population ***,lake visibility was very important to make a difference from other existing facilities in the ***,it was included as constraints and lake visible areas were extracted at the final stage of the *** ski areas were mapped in three levels as professional,intermediate and beginner *** of the suitable areas was selected as a sample projection and for the 3D simulation of the ski investment *** costs and benefits were *** was found that a ski tourism area investment can be amortized in 3 years in the region.

关键词： Winter sports and tourism Decision making 3D simulation and modelling Landscape planning gis

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gis屏蔽罩松动状态特性仿真及试验分析

高压电器 2024年第6期60卷 19-26页

作者：刘咏飞黄强赵科杨景刚高山施景垒鲁露国网江苏省电力有限公司电力科学研究院gis设备运维检修技术实验室南京211103 上海睿深电子科技有限公司上海201108

机械类缺陷是gis设备运行阶段的常见缺陷之一。针对机械缺陷导致gis异常振动问题开展机理研究,能够有效排查现场设备故障隐患。文中首先通过有限元建模,对某126 kV三相共体式gis运行时可能出现的屏蔽罩松动缺陷进行仿真,探究设备在缺陷... 详细信息

机械类缺陷是gis设备运行阶段的常见缺陷之一。针对机械缺陷导致gis异常振动问题开展机理研究,能够有效排查现场设备故障隐患。文中首先通过有限元建模,对某126 kV三相共体式gis运行时可能出现的屏蔽罩松动缺陷进行仿真,探究设备在缺陷状态下的异常振动机理及特征。其次,分别对建立的gis正常模型和屏蔽罩松动模型进行磁固耦合仿真,通过后处理获得了筒体上的振动结果。最后,搭建了同一型号的gis试验平台进行了缺陷模拟试验,对相同缺陷状态下gis运行振动信号进行了检测分析。结果表明,文中所分析的126 kV gis设备内部出现屏蔽罩松动缺陷时,振动信号中的主频会发生偏移,300 Hz特征频率明显增大,仿真和试验一致性较好。文中的研究成果可用于gis屏蔽罩松动缺陷下的振动信号异常判断,采用的数值仿真及试验模型相结合的分析方法也可为更多缺陷类型研究提供思路。

关键词：三相共体式gis 异常机械振动屏蔽罩松动振动仿真

1990-2020年喜马拉雅山中段北坡冰川变化遥感监测

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地理研究 2024年第7期43卷 1862-1877页

作者：冀琴范亦霏童丽媛周凌翔吴晋扬重庆师范大学地理与旅游学院重庆401331 gis应用研究重庆市高校重点实验室重庆401331

喜马拉雅山作为中纬度地区冰川作用中心之一,其变化的时空格局特征与气候环境息息相关。本文基于Landsat系列遥感影像,采用比值阈值及目视解译法,分析1990-2020年喜马拉雅山中段北坡冰川的分布和变化特征。结果表明:(1) 2020年冰川面积... 详细信息

喜马拉雅山作为中纬度地区冰川作用中心之一,其变化的时空格局特征与气候环境息息相关。本文基于Landsat系列遥感影像,采用比值阈值及目视解译法,分析1990-2020年喜马拉雅山中段北坡冰川的分布和变化特征。结果表明:(1) 2020年冰川面积为2763.72 km^(2),较1990年减少了622.35 km^(2),冰川呈持续退缩状态,年均退缩率为0.61%/a。(2)从地形分布特征看,冰川面积分布随海拔变化呈正态分布趋势,冰川退缩最为显著的区域集中在5500~6000 m,退缩面积达321.03 km^(2)。在3500~4000 m范围内,冰川的年均退缩率最大,为1.12%/a。(3)研究区内非表碛物覆盖型冰川分布面积远高于表碛物覆盖型冰川,且前者年均退缩率(0.78%/a)远大于后者(0.31%/a),表明研究区内表碛物对冰川融化有一定程度的抑制作用。(4) 2020年研究区山谷冰川分布面积最多,为1649.63 km^(2),其次为悬冰川、冰斗-山谷冰川和冰斗冰川,面积分别为574.71 km^(2)、429.39 km^(2)和105.59 km^(2),而平顶冰川分布面积最少,仅为2.40 km^(2)。(5)值得注意的是,山谷冰川中超过一半的冰川表面被表碛物覆盖,而在平顶冰川中并未发现表碛物覆盖型冰川。不同类型冰川受表碛物覆盖影响的程度不同,总体而言非表碛物覆盖型冰川退缩程度更为剧烈,其中在表碛物覆盖区域,悬冰川的年均退缩速率最快,达1.04%/a。

关键词：喜马拉雅山中段冰川变化冰川类型遥感监测

Contribution of SAR Radar Imagery in the Detection of Suspicious Vessels in the Ivorian EEZ

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World Journal of Engineering and Technology 2024年第1期12卷 200-212页

作者： Koffi Cyprien Yoboue Jean-Baptiste Kassi Eric Valère Djagoua Tiemelé Jacque-André Laboratory of Remote Sensing and gis University Center for Research and Application in Remote Sensing (CURAT) Félix Houphouet-Boigny University of Abidjan Cocody Ivory Coast

The present work proposed a method for match SAR and AIS data to detect vessels carrying out suspicious activity in the Ivorian EEZ. Two superposition methods, detected AIS and SAR data, based on point-to-point association on the one hand and point-to-line on the other hand, were used to detect suspicious vessels in Ivorian marine waters. The results showed that most vessels detected in the Ivorian EEZ do not declare their positions to avoid being spotted. These funds are likely to practice illegal, undeclared and unregulated fishing (INN fishing). This clandestine activity is very recurrent in Ivorian waters. This is illustrated by the number of suspicious vessels detected by SAR radar imagery which is greater compared to declared or authorized vessels.

关键词： INN Fishing CFAR Algorithm AIS Sentinel-1A Ivory Coast

Spatiotemporal changes in sunshine duration and its influential factors in Chongqing,China from 1961 to 2020

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Journal of Mountain Science 2024年第6期21卷 2005-2024页

作者： LI Jun XIA Hongxuan JIANG Jinge XU Weifeng WEN Di XU Junfeng College of Geography and Tourism Chongqing Normal UniversityChongqing 401331China Key Laboratory of gis Application of Chongqing Chongqing 401331China Chongqing Key Laboratory of Earth Surface Processes and Environmental Remote Sensing in Three Gorges Reservoir area Chongqing 401331China Institute of Remote Sensing and Earth Sciences School of Institute of Remote Sensing and Earth SciencesSchool of ScienceHangzhou Normal UniversityHangzhou 311121China

The surface solar radiation in most parts of the world has undergone a phenomenon known as global dimming and brightening,characterized by an initial decrease followed by an *** a result,the sunshine duration(SD)has decreased in the past 60 *** the backdrop of global dimming and brightening,SD has decreased to varying degrees in many regions of *** the observed data of SD,cloud amount(total cloud amount and low cloud amount,abbreviated as TCA and LCA),precipitation,and relative humidity(RH)from 34 meteorological stations in Chongqing during the period of 1961-2020,along with a digital elevation model(DEM)with a resolution of 90 m,this study analyzed the spatiotemporal variations and influencing factors of *** analysis employed methods such as linear regression,Mann-Kendall test,wavelet transformation,and DEM-based possible SD distributed *** results showed that the annual SD in Chongqing has significantly decreased over the last 60 years,with a decreasing interannual trend rate(ITR)of 40.4 h/*** for no obvious trend in spring,SD decreased significantly in summer,autumn and winter at the ITR of 21.1 h/10a,8.5 h/10a and 7.5 h/10a,*** abrupt decrease in the annual SD was found in *** difference before and after the abrupt decrease was 177.7 *** difference before and after the abrupt decrease was 177.7 *** annual SD possessed the oscillation period of *** spatial heterogeneity of the mean annual SD during the last 60 years was *** distribution of SD in Chongqing is high in the northeast and low in the *** addition,about 73%of the total area in Chongqing showed a significant and very significant decreasing *** regions with significant changes are mainly concentrated in the regions with altitudes of 200~1000 *** increasing LCA was the main cause of the decrease of the annual SD in the regions with 200-400 m altitude decreased the most and changed the *** LCA is the prim

关键词： Sunshine duration Spatiotemporal changes Mann-Kendall test Wavelet analysis Geodetector model