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多模态视觉语言表征学习模型及其对抗样本攻防技术综述
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作者 曾诚 葛云洁 +1 位作者 赵令辰 王骞 《计算机研究与发展》 北大核心 2025年第9期2208-2232,共25页
随着计算机视觉、自然语言处理与深度学习技术的快速发展,多模态视觉语言表征学习模型在图像描述、文本生成图像、视觉问答等任务中展现出了卓越的性能,已成为当前学术界与工业界共同关注的研究热点.然而,这类模型的多模态特性和复杂性... 随着计算机视觉、自然语言处理与深度学习技术的快速发展,多模态视觉语言表征学习模型在图像描述、文本生成图像、视觉问答等任务中展现出了卓越的性能,已成为当前学术界与工业界共同关注的研究热点.然而,这类模型的多模态特性和复杂性为攻击者提供了更加多样的攻击途径,攻击者可以通过对抗样本引导模型输出错误的、有害的或虚假的内容,使该类模型面临的安全威胁日益严峻.系统地梳理了多模态视觉语言模型的研究现状,同时,对近年来出现的针对该类模型的对抗样本攻击方法及其防御策略进行了分类总结,详细归纳了相关研究的基本原理、实施方法与研究结论.在此基础上,对多模态视觉语言表征学习的安全研究现状与未来方向进行了探讨,并展望了视觉语言表征学习技术在未来结合可解释性技术的应用前景. 展开更多
关键词 表征学习 视觉语言学习 对抗性攻击 对抗性防御 网络空间安全
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面向单目可见光环境的自适应双手重建网络
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作者 廖国琼 黄龙杰 +2 位作者 李清新 辜勇 李海波 《图学学报》 北大核心 2025年第4期837-846,共10页
准确重建双手手部网格对于自然的人机交互体验来说是一个至关重要的过程,但由于双手的遮挡、户外收集双手交互数据集的复杂性和复杂的光照环境干扰等因素导致双手手部重建任务仍极具挑战性。目前已有的工作大多是在环境干扰比较小的实... 准确重建双手手部网格对于自然的人机交互体验来说是一个至关重要的过程,但由于双手的遮挡、户外收集双手交互数据集的复杂性和复杂的光照环境干扰等因素导致双手手部重建任务仍极具挑战性。目前已有的工作大多是在环境干扰比较小的实验室等场景下取得的的良好效果,而在复杂的光照场景中的重建效果仍不佳。为了解决上述问题,提出一种面向单目可见光环境的自适应手部重建网络。通过引入单手检测框和使用2D复杂光照场景数据集进行弱监督等策略使得模型得以对复杂光照场景产生泛化性;设计的双手特征交互器得以有效建立左右手特征的远距离依赖关系,缓解了单手检测框缺乏双手交互信息的问题;针对如何有效融合交互特征与单手特征的问题,设计了自适应融合的策略,增强了模型的鲁棒性。实验结果表明,在包含多个复杂光照场景的HIC数据集中取得了最佳的效果。 展开更多
关键词 复杂光照场景 手部网格 双手交互 弱监督 特征融合
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基于Internet+“运筹学”课程教学改革探索——以农林院校为例
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作者 占青义 谢向东 《教育教学论坛》 2025年第36期151-154,共4页
新时代,随着人工智能技术的发展,高校“运筹学”课程教学面临着比较显著的困难。如何从实际出发,切实有效提高“运筹学”的教学效果成为一个比较迫切的教改课题。通过参考国内外同行的经验,结合笔者多年的教学实践,从提高“运筹学”课... 新时代,随着人工智能技术的发展,高校“运筹学”课程教学面临着比较显著的困难。如何从实际出发,切实有效提高“运筹学”的教学效果成为一个比较迫切的教改课题。通过参考国内外同行的经验,结合笔者多年的教学实践,从提高“运筹学”课程教学效果的角度,基于“Internet+”深度理性地审视农林院校“运筹学”课程教学困境,拟在优化教学内容的选择与组织、重视数学基础理论、强化非线性规划的教与学、加强实践教学与算法改进等四个方面,提出课程教学改革的优化策略,并通过教学实践,进一步验证方法的适用性和可行性,以期为其他高校“运筹学”教学改革与课程建设提供借鉴与参考。 展开更多
关键词 运筹学 线性规划 函数的极值 线性方程组的求解 教学改革
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光的衍射的理论分析及Mathematica仿真模拟 被引量:7
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作者 陈学文 罗源源 +1 位作者 张家伟 姚雪 《西南师范大学学报(自然科学版)》 CAS 北大核心 2018年第11期156-161,共6页
首先利用旋转矢量从理论上推出了光的多缝干涉的光强分布公式,并将狭缝数N→!,从而得到光的单缝衍射光强分布,进而在多缝干涉和单缝衍射的基础上得到了光栅衍射光强分布.此外,将Mathematica仿真模拟应用到光的衍射课堂教学中.基于Mathem... 首先利用旋转矢量从理论上推出了光的多缝干涉的光强分布公式,并将狭缝数N→!,从而得到光的单缝衍射光强分布,进而在多缝干涉和单缝衍射的基础上得到了光栅衍射光强分布.此外,将Mathematica仿真模拟应用到光的衍射课堂教学中.基于Mathematica软件的交互功能,利用Mathematica的Manipulate命令对单缝夫琅禾费衍射和光栅衍射做了仿真模拟,获得了相应的可以调节各参数(如波长、狭缝宽度、光栅常数等)的动态图形.这对学生建立清晰的物理图像,更好地理解光的衍射的物理规律有很好的促进作用. 展开更多
关键词 光的衍射 旋转矢量 MATHEMATICA 虚拟仿真
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基于最小二乘的量化评估页岩气压裂改造效果方法
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作者 邓才 孙可心 +1 位作者 文欢 胡朝浪 《工程科学与技术》 北大核心 2025年第4期103-111,共9页
在页岩气压裂改造过程中,水平井分段多簇压裂技术是实现页岩气高效开发的关键技术之一,但这项技术缺乏低成本、可量化的评价方法。页岩气压裂改造效果的好坏通常通过井下射孔的有效开启个数来判断,有效孔眼开启得多,则压裂改造效果好,... 在页岩气压裂改造过程中,水平井分段多簇压裂技术是实现页岩气高效开发的关键技术之一,但这项技术缺乏低成本、可量化的评价方法。页岩气压裂改造效果的好坏通常通过井下射孔的有效开启个数来判断,有效孔眼开启得多,则压裂改造效果好,反之则差。针对目前页岩气压裂改造技术评估的瓶颈,本文设计一种基于非线性最小二乘的量化评估模型,该模型结合井下各项摩阻理论与孔眼扩展方程,实现了有效开启射孔数的高效计算。首先,根据压裂过程中阶梯降排量测试中的总摩阻(井筒摩阻、孔眼摩阻、近井摩阻之和)与压裂液排量的对应关系,构造了页岩气摩阻拟合的非线性最小二乘目标函数,从而拟合出各项摩阻系数,尤其是孔眼摩阻系数;然后,结合孔眼摩阻方程和孔眼扩展方程,创建了射孔有效开启孔数和磨蚀后射孔平均直径的计算模型;最后,将该模型应用于工业生产,根据有效开启射孔数和磨蚀后射孔平均直径的计算结果,得到该井段水平井分段多簇压裂改造的实施效果评估依据。在摩阻拟合方面,相比原有模型,本文模型具有可区分所有拟合参数的优点,并且添加了符合工程实际的约束条件,使得拟合结果符合工程需求。所提出的评估方法具有数学理论完备的优点,且实施成本低、效率高,可作为评价压裂改造的新方法。 展开更多
关键词 页岩气开采 水平井分段多簇压裂 摩阻拟合 非线性最小二乘 有效开启孔数
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病例队列设计下乳腺癌患者雌二醇水平及其生存数据的联合建模研究
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作者 吴梦娟 张涛 +2 位作者 高春洁 赵婷 王蕾 《中国全科医学》 北大核心 2025年第14期1765-1772,共8页
背景乳腺癌是一种性激素受体依赖的恶性肿瘤,雌二醇(E2)的动态变化在乳腺癌发展过程中起着非常重要的作用;经典病例队列设计完全忽略未选入样本的信息,容易产生估计偏倚。目的探究乳腺癌患者E2水平动态变化对其生存预后的影响,评估改良... 背景乳腺癌是一种性激素受体依赖的恶性肿瘤,雌二醇(E2)的动态变化在乳腺癌发展过程中起着非常重要的作用;经典病例队列设计完全忽略未选入样本的信息,容易产生估计偏倚。目的探究乳腺癌患者E2水平动态变化对其生存预后的影响,评估改良病例队列设计的优良性。方法对2015—2019年于新疆医科大学附属肿瘤医院经病理学检查确诊为乳腺癌的8226例患者进行随访,以患者确诊时间作为随访时间起点、患者因乳腺癌死亡为结局事件,随访截止日期为2021-12-31。收集患者的人口学特征、免疫组化指标、临床病理特征以及生存状态等,并对患者的血清E2水平进行纵向测量。基于经典病例队列设计,通过纳入病例队列样本外患者的生存数据改良病例队列设计。在经典及改良病例队列设计下采用线性混合效应模型和Cox比例风险模型分别拟合乳腺癌患者的纵向数据(纵向子模型)和生存数据(生存子模型),并建立纵向与时间-事件数据的联合模型;进一步采用马尔可夫链蒙特卡罗算法对联合模型参数进行估计;此外,通过受试者工作特征曲线下面积(AUC)以及预测误差(PE)比较经典及改良病例队列设计下联合模型的区分度与校准度。结果基于纳入与排除标准,本研究全队列中共纳入895例乳腺癌患者作为研究对象,其中53例患者因乳腺癌死亡。患者中位随访时间约为28个月。从全队列中抽取1/4的患者作为随机子队列,与随机子队列外在随访期间死亡的患者合并作为经典病例队列设计的样本,其中,包含236例患者的生存数据、1062人次E2水平的测量值。此外,在经典病例队列设计的基础上,纳入经典病例队列样本之外在随访期间存活的乳腺癌患者(G_(4))的生存数据,作为改良病例队列设计的样本(共包含895例患者的生存数据、236例患者1062人次的E2水平测量值,其中认为存在2958人次E2水平测量的纵向缺失值)。经典和改良病例队列设计下的联合模型结果均显示E2水平动态变化是乳腺癌患者预后的影响因素,且lg(E2)纵向每增加1个单位,患者的死亡风险将分别增加23%(HR=1.23,R^=1.015)和8%(HR=1.08,R^=1.020)。此外,改良病例队列设计下的联合模型展现出更好的区分度与校准度(AUC=0.706~0.962,PE=0.0012~0.0108)。结论乳腺癌患者E2水平纵向升高可能会导致患者生存概率降低。病例队列设计下联合模型能够对纵向与生存数据同时进行分析,且改良病例队列设计优于经典病例队列设计。 展开更多
关键词 乳腺癌 雌二醇 病例队列设计 联合模型 生存数据
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Pricing Multi-Strike Quanto Call Options on Multiple Assets with Stochastic Volatility, Correlation, and Exchange Rates
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作者 Boris Ter-Avanesov Gunter Meissner 《Applied Mathematics》 2025年第1期113-142,共30页
Quanto options allow the buyer to exchange the foreign currency payoff into the domestic currency at a fixed exchange rate. We investigate quanto options with multiple underlying assets valued in different foreign cur... Quanto options allow the buyer to exchange the foreign currency payoff into the domestic currency at a fixed exchange rate. We investigate quanto options with multiple underlying assets valued in different foreign currencies each with a different strike price in the payoff function. We carry out a comparative performance analysis of different stochastic volatility (SV), stochastic correlation (SC), and stochastic exchange rate (SER) models to determine the best combination of these models for Monte Carlo (MC) simulation pricing. In addition, we test the performance of all model variants with constant correlation as a benchmark. We find that a combination of GARCH-Jump SV, Weibull SC, and Ornstein Uhlenbeck (OU) SER performs best. In addition, we analyze different discretization schemes and their results. In our simulations, the Milstein scheme yields the best balance between execution times and lower standard deviations of price estimates. Furthermore, we find that incorporating mean reversion into stochastic correlation and stochastic FX rate modeling is beneficial for MC simulation pricing. We improve the accuracy of our simulations by implementing antithetic variates variance reduction. Finally, we derive the correlation risk parameters Cora and Gora in our framework so that correlation hedging of quanto options can be performed. 展开更多
关键词 Quanto Option Multi-Strike Option Stochastic Volatility (SV) Stochastic Correlation (SC) Stochastic Exchange Rates (SER) CORA GORA Correlation Risk
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The Swimming Performance of Mollies and Their Interaction with Tiger Barb Fish when Exposed to Concurrent Low pH and Elevated Temperature
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作者 Rostern Tembo 《Journal of Environmental Science and Engineering(B)》 2025年第3期96-102,共7页
The global climate change and ocean acidification brought about by the anthropogenic release of carbon dioxide gas into the air is considered one of the greatest problems facing marine life.In this research,the intera... The global climate change and ocean acidification brought about by the anthropogenic release of carbon dioxide gas into the air is considered one of the greatest problems facing marine life.In this research,the interactions between two species of fish(the gold mollies and tiger barb)were investigated under two different environmental conditions,an elevated temperature of 28°C and a low pH of 5 and a normal pH of 7 and a normal temperature of 24°C.The mollies at pH 7 and a temperature of 24°C exhibited scary interactions with the tiger barb.They were scared and ran fast away from the tiger barb.At the same time,the mollies at pH 5 and a temperature of 28°C interacted normally as though both species were one species showing behavioral changes due to these two stressors(pH 5 and elevated temperature 28°C).This could be the only research that has addressed how the kinematics and swimming interactions of two species of fish changed in response to elevated temperature and low pH. 展开更多
关键词 pH 5 pH 7 temperature of 28°C temperature of 24°C gold mollies tiger barb.
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复积分常用计算方法探究
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作者 杨凯然 《黑河学院学报》 2025年第4期185-188,共4页
复积分理论作为复分析中的重要研究内容,在计算具体复积分时能快速、准确找到合适的方法,可以对学习更深层次的复分析理论打下坚实基础。通过对积分路径是否为闭合曲线,以及被积函数在积分区域是否有奇点进行分析归纳,总结出几类常用的... 复积分理论作为复分析中的重要研究内容,在计算具体复积分时能快速、准确找到合适的方法,可以对学习更深层次的复分析理论打下坚实基础。通过对积分路径是否为闭合曲线,以及被积函数在积分区域是否有奇点进行分析归纳,总结出几类常用的计算方法,包含原函数法、参数方程法、柯西积分定理、复合闭路定理、柯西积分公式、高阶导数公式、柯西留数定理等,并详细介绍了各个方法之间的联系与区别。 展开更多
关键词 复积分 奇点 柯西积分定理 高阶导数公式
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Prediction and Modelling of Land Use Change in Pesawaran District Lampung Using ANN and Cellular Automata
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作者 Irma Lusi Nugraheni Mustofa Usman Sutarto Sutarto 《Journal of Environmental & Earth Sciences》 2025年第6期46-62,共17页
The simultaneous increase in development in Pesawaran Regency is closely correlated with the intense competi-tion for land use.However,low policy implementation effectiveness has led to construction beyond designated ... The simultaneous increase in development in Pesawaran Regency is closely correlated with the intense competi-tion for land use.However,low policy implementation effectiveness has led to construction beyond designated spatial plan.The study used a quantitative survey using Landsat images in 2016,2019,and 2022.The data analysis techniques used geographic information systems integrated with Artificial Neural Network(ANN)and Cellular Automata(CA)models.This study aims to predict land-use change in 2031,evaluate its alignment with spatial planning,and provide guidance for controlling land-use change.The results showed that there has been an increase in land use.In 2019,built-up land reached 7,069.65 Ha.The model shows its ability to predict land simulation and transformation,where it is predicted that built-up land in 2031 will experience an increase of up to 40.10%,so development and change cannot be avoided every year.This study also suggests that decision-makers and local governments should reconsider spatial planning strategies.This study shows that there have been many land use changes from 2016 to 2022.The model shows its ability to predict simulation and land transformation.When using the model,there are many changes in the land use area in 2031.This is due to wet agricultural land turning into built-up land by almost 70%.This study shows that road network influence land-use change.The cellular automata model managed to capture the complexity with simple rules.Predictions for future research should focus on conserving wetlands and primary forests. 展开更多
关键词 Land Use Model System Information Geography Cellular Automata Artificial Neural Network(ANN)
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Mars Clocks and other novel analog clocks,using Earth Standard Seconds
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作者 Eric Wim Flesch Reggis Eric Sanders 《Astronomical Techniques and Instruments》 2025年第3期210-217,共8页
We present analog clocks fitted to the Mars solar day.These clocks use the standard Earth-based second of the International System of Units(SI)as their operational unit of time,unlike current practice for Mars timekee... We present analog clocks fitted to the Mars solar day.These clocks use the standard Earth-based second of the International System of Units(SI)as their operational unit of time,unlike current practice for Mars timekeeping.We discuss the importance of preserving the SI second.On this basis,we identify the two analog clocks most suitable for public use by a future Mars population.These are a 20-hour clock with a hand motion similar to that of the standard Earth clock,and a 24-hour clock with a novel“Martian”hand motion which strikes the hour when all 3 hands converge onto that hour mark on the dial.Both clocks have Earth-day equivalents to assist learning.We also present a 24-hour“SpaceClock”,similar to the Martian clock but with no favored reference plane,hence equally readable from any viewing orientation. 展开更多
关键词 CLOCK MARS
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Digital Twins and Cyber-Physical Systems:A New Frontier in Computer Modeling
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作者 Vidyalakshmi G S Gopikrishnan +2 位作者 Wadii Boulila Anis Koubaa Gautam Srivastava 《Computer Modeling in Engineering & Sciences》 2025年第4期51-113,共63页
Cyber-Physical Systems(CPS)represent an integration of computational and physical elements,revolutionizing industries by enabling real-time monitoring,control,and optimization.A complementary technology,Digital Twin(D... Cyber-Physical Systems(CPS)represent an integration of computational and physical elements,revolutionizing industries by enabling real-time monitoring,control,and optimization.A complementary technology,Digital Twin(DT),acts as a virtual replica of physical assets or processes,facilitating better decision making through simulations and predictive analytics.CPS and DT underpin the evolution of Industry 4.0 by bridging the physical and digital domains.This survey explores their synergy,highlighting how DT enriches CPS with dynamic modeling,realtime data integration,and advanced simulation capabilities.The layered architecture of DTs within CPS is examined,showcasing the enabling technologies and tools vital for seamless integration.The study addresses key challenges in CPS modeling,such as concurrency and communication,and underscores the importance of DT in overcoming these obstacles.Applications in various sectors are analyzed,including smart manufacturing,healthcare,and urban planning,emphasizing the transformative potential of CPS-DT integration.In addition,the review identifies gaps in existing methodologies and proposes future research directions to develop comprehensive,scalable,and secure CPSDT systems.By synthesizing insights fromthe current literature and presenting a taxonomy of CPS and DT,this survey serves as a foundational reference for academics and practitioners.The findings stress the need for unified frameworks that align CPS and DT with emerging technologies,fostering innovation and efficiency in the digital transformation era. 展开更多
关键词 Cyber physical systems digital twin efficiency Industry 4.0 robustness and intelligence
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Multimodal Learning in Image Processing
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作者 Zhixin Chen Gautam Srivastava Shuai Liu 《Computers, Materials & Continua》 2025年第2期3615-3618,共4页
1 Introduction onMultimodal Learning in Image Processing IP(Image processing),as a classical research domain in computer application technology,has been researched for decades.It is one of the most important research ... 1 Introduction onMultimodal Learning in Image Processing IP(Image processing),as a classical research domain in computer application technology,has been researched for decades.It is one of the most important research directions in computer vision,which is the basis for many current hotspots such as intelligent transportation/education/industry,etc.Because image processing is the strongest link for AI(artificial intelligence)applying to real world application,it has been a challenging research field with the development of AI,from DNN(deep convolutional network),Attention/LSTM(long-short term memory),to Transformer/Diffusion/Mamba based GAI(generated AI)models,e.g.,GPT and Sora[1].Today,the description ability of single-model feature limits the performance of image processing.More comprehensive description of the image is required to match the computational performance of current large scale models. 展开更多
关键词 IMAGE COMPUTER LSTM
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Distribution and human health risk assessment of cadmium,arsenic,mercury,lead,and iron in settling particles from the transboundary estuary in three rivers of Cote d’Ivoire,West Africa
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作者 Dehoule N’Guessan Fulgence Kouassi Assy Eudes Yapi +2 位作者 N’Guessan Louis Berenger Kouassi Koffi Marcellin Yao Aoua Sougo Coulibaly 《Acta Geochimica》 2025年第5期1040-1058,共19页
Pollution of transboundary rivers can result from anthropogenic activities in their watersheds.In this study,sediment traps were deployed to determine the fluxes,concentrations,and health risks associated with arsenic... Pollution of transboundary rivers can result from anthropogenic activities in their watersheds.In this study,sediment traps were deployed to determine the fluxes,concentrations,and health risks associated with arsenic,cadmium,mercury,lead,and iron in the estuaries of three transboundary rivers(Comoé,Bia,and Tanoé)in West Africa.Thus,the analysis of metal-associated sedimentation particle samples collected in rainy,flood,and dry seasons was required.Sediment traps were used to calculate the metal fluxes associated with sedimentation particles towards the Atlantic Ocean.Finally,the carcinogenic and non-carcinogenic risks of ingestion and dermal contact associated with sedimentation particles were assessed.The results showed that the total concentrations of trace metals in particulate matter were higher than in the UCC(Upper Crust Continental),with the exception of lead.The highest fluxes of lead,mercury,iron and arsenic associated with sedimented particles were observed during flood periods in the estuary of the Comoé,Bia and Tanoérivers.Cadmium fluxes associated with sedimentation particles were highest in the rainy season in the Bia and Comoéestuaries and in the flood season in the Tanoéestuary.Pearson’s correlation analysis and the enrichment factor showed that the trace metals were derived from anthropogenic activities such as mining and farming.In addition,contamination indices showed that sediment particles in the estuaries of the three rivers were severely contaminated with mercury.However,the results of potential human health risks associated with trace metals show that there is no probability of exposure of the community to harmful and carcinogenic effects through ingestion and dermal absorption of sediment particles.It is essential to integrate the information from this study into policy-and decision-making processes for better management of transboundary river water resources in coastal countries,particularly the Côte d’Ivoire. 展开更多
关键词 Trace metals Settling particles Transboundary rivers Carcinogenic and non-carcinogenic risks ESTUARY West Africa
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Use of supervised and unsupervised approaches to make zonal application maps for variable-rate application of crop growth regulators in commercial cotton fields
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作者 ANDREA Maria C.da S. OLIVEIRA Cristiano F.de +7 位作者 MOTA Fabrícia C.M. SANTOS Rafael C.dos RODRIGUES JUNIOR Edilson F. BIANCHI Lucas M. OLIVEIRA Rodrigo S.de GOUVEIA Caio M.de BARBOSA Victor G.S. BISPO E SILVA Marco A. 《Journal of Cotton Research》 2025年第1期1-20,共20页
Background Zonal application maps are designed to represent field variability using key variables that can be translated into tailored management practices.For cotton,zonal maps for crop growth regulator(CGR)applicati... Background Zonal application maps are designed to represent field variability using key variables that can be translated into tailored management practices.For cotton,zonal maps for crop growth regulator(CGR)applications under variable-rate(VR)strategies are commonly based exclusively on vegetation indices(VIs)variability.However,VIs often saturate in dense crop vegetation areas,limiting their effectiveness in distinguishing variability in crop growth.This study aimed to compare unsupervised framework(UF)and supervised framework(SUF)approaches for generat-ing zonal application maps for CGR under VR conditions.During 2022-2023 agricultural seasons,an UF was employed to generate zonal maps based on locally collected field data on plant height of cotton,satellite imagery,soil texture,and phenology data.Subsequently,a SUF(based on historical data between 2020-2021 to 2022-2023 agricultural seasons)was developed to predict plant height using remote sensing and phenology data,aiming to replicate same zonal maps but without relying on direct field measurements of plant height.Both approaches were tested in three fields and on two different dates per field.Results The predictive model for plant height of SUF performed well,as indicated by the model metrics.However,when comparing zonal application maps for specific field-date combinations,the predicted plant height exhibited lower variability compared with field measurements.This led to variable compatibility between SUF maps,which utilized the model predictions,and the UF maps,which were based on the real field data.Fields characterized by much pronounced soil texture variability yielded the highest compatibility between the zonal application maps produced by both SUF and UF approaches.This was predominantly due to the greater consistency in estimating plant development patterns within these heterogeneous field environments.While VR application approach can facilitate product savings during the application operation,other key factors must be considered.These include the availability of specialized machinery required for this type of applications,as well as the inherent operational costs associated with applying a single CGR product which differs from the typical uniform rate applications that often integrate multi-ple inputs.Conclusion Predictive modeling shows promise for assisting in the creation of zonal application maps for VR of CGR applications.However,the degree of agreement with the actual variability in crop growth found in the field should be evaluated on a field-by-field basis.The SUF approach,which is based on plant heigh prediction,demonstrated potential for supporting the development of zonal application maps for VR of CGR applications.However,the degree to which this approach aligns itself with the actual variability in crop growth observed in the field may vary,necessi-tating field-by-field evaluation. 展开更多
关键词 Cotton Site-specific management Crop growth regulator Unsupervised framework Supervised framework Zonal application maps
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Water Erosion Factors Modeling in the N’Zérékoré City, Republic of Guinea
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作者 Alhassane Diallo Oumar Keita +1 位作者 Ibrahima Sory Mamikouny CAMARA Boubacar Diallo 《Journal of Environmental Science and Engineering(A)》 2025年第4期206-216,共11页
Soil erosion from water has become a relevant issue at global level.In Guinea in particular,erosion has worrying effects,due to natural conditions and human impact,especially in the Nzérékore city in forest ... Soil erosion from water has become a relevant issue at global level.In Guinea in particular,erosion has worrying effects,due to natural conditions and human impact,especially in the Nzérékore city in forest region.This paper proposed a soil erosion modeling by rainfall effect in the prefecture of N'Zérékoré.To achieve this objective,monthly and annual rainfall data for the N'Zérékorécity were collected at the meteorological station over the period from 1980 to 2024.The analysis of rainfall aggressiveness was possible using the Fournier index.For data processing,we used Microsoft Excel,Python and the ARIMA(AutoRegressive Integrated Moving Average)model for soil aggressiveness predicted by rainfall.It was found that,from 2000 to 2009,erosion was higher compared to other periods with a rate of 60%,or 6 years of high rainfall aggression.From the periods 1990 to 1999 and 2010 to 2019,the lowest rainfall aggressiveness was recorded,with 60%or 6 years of low erosivity.However,from period 1980 to 1989 the highest rate(70%)of very high rainfall erosivity was recorded.The results show three levels of rainfall aggressiveness on an annual scale:a very high level of erosivity with a rate of 22.2%or 10 years,followed by a high level of 35.6%or 16 years of strong erosion.The moderate erosivity level corresponds to 42.2%or 19 years.The model predicts a stability of the erosivity index around 77.14 over the period 2025-2034.During the forty(45)years the rainfall erosivity index was very unstable characterized by strong erosion,however it would be stable in the next ten(10)years. 展开更多
关键词 Rainfall factor water erosion erosivity index N’Zérékoré
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Role of deep learning in cognitive healthcare:Wearable signal analysis,algorithms,benefits,and challenges
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作者 Md.Sakib Bin Alam Aiman Lameesa +4 位作者 Senzuti Sharmin Shaila Afrin Shams Forruque Ahmed Mohammad Reza Nikoo Amir H.Gandomi 《Digital Communications and Networks》 2025年第3期642-670,共29页
Deep Learning(DL)offers promising solutions for analyzing wearable signals and gaining valuable insights into cognitive disorders.While previous review studies have explored various aspects of DL in cognitive healthca... Deep Learning(DL)offers promising solutions for analyzing wearable signals and gaining valuable insights into cognitive disorders.While previous review studies have explored various aspects of DL in cognitive healthcare,there remains a lack of comprehensive analysis that integrates wearable signals,data processing techniques,and the broader applications,benefits,and challenges of DL methods.Addressing this limitation,our study provides an extensive review of DL’s role in cognitive healthcare,with a particular emphasis on wearables,data processing,and the inherent challenges in this field.This review also highlights the considerable promise of DL approaches in addressing a broad spectrum of cognitive issues.By enhancing the understanding and analysis of wearable signal modalities,DL models can achieve remarkable accuracy in cognitive healthcare.Convolutional Neural Network(CNN),Recurrent Neural Network(RNN),and Long Short-term Memory(LSTM)networks have demonstrated improved performance and effectiveness in the early diagnosis and progression monitoring of neurological disorders.Beyond cognitive impairment detection,DL has been applied to emotion recognition,sleep analysis,stress monitoring,and neurofeedback.These applications lead to advanced diagnosis,personalized treatment,early intervention,assistive technologies,remote monitoring,and reduced healthcare costs.Nevertheless,the integration of DL and wearable technologies presents several challenges,such as data quality,privacy,interpretability,model generalizability,ethical concerns,and clinical adoption.These challenges emphasize the importance of conducting future research in areas such as multimodal signal analysis and explainable AI.The findings of this review aim to benefit clinicians,healthcare professionals,and society by facilitating better patient outcomes in cognitive healthcare. 展开更多
关键词 Cognitive healthcare Deep learning Wearable sensor Convolutional neural network Recurrent neural network
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GLOBAL BIFURCATION AND CHAOS IN A VAN DER POL-DUFFING-MATHIUE SYSTEM WITH A SINGLE-WELL POTENTIAL OSCILLATOR 被引量:1
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作者 Xu, J Wang, C +1 位作者 Chen, YS Lu, QS 《Acta Mechanica Solida Sinica》 SCIE EI 1997年第3期262-275,共14页
The global bifurcation and chaos are investigated in this paper for a van der Pol-Duffing-Mathieu system with a single-well potential oscillator by means of nonlinear dynamics. The autonomous system corresponding to t... The global bifurcation and chaos are investigated in this paper for a van der Pol-Duffing-Mathieu system with a single-well potential oscillator by means of nonlinear dynamics. The autonomous system corresponding to the system under discussion is analytically studied to draw all global bifurcation diagrams in every parameter space. These diagrams are called basic bifurcation ones. Then fixing parameter in every space and taking the parametrically excited amplitude as a bifurcation parameter, we can observe how to evolve from a basic bifurcation diagram to a chaos pattern in terms of numerical methods. The results are sufficient to show that the system has distinct dynamic behavior. Finally, the properties of the basins of attraction are observed and the appearance of fractal basin boundaries heralding the onset of a loss of structural integrity is noted in order to consider how to control the extent and the rate of the erosion in the next paper. 展开更多
关键词 global bifurcation CHAOS nonlinear vibration basin FRACTAL
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本科实习护生人格的聚类分析及其对职业认同的影响研究 被引量:2
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作者 唐婷婷 王杰 +2 位作者 张小磊 张燕 王霞 《护理管理杂志》 CSCD 2024年第6期479-482,共4页
目的通过聚类分析识别本科实习护生的人格类型,并分析其对职业认同的影响。方法2021年10月至12月采用便利抽样法对山东省3所医院的293名本科实习护生进行职业认同问卷和大五人格量表调查。结果聚类分析显示,本科实习护生共存在3种人格类... 目的通过聚类分析识别本科实习护生的人格类型,并分析其对职业认同的影响。方法2021年10月至12月采用便利抽样法对山东省3所医院的293名本科实习护生进行职业认同问卷和大五人格量表调查。结果聚类分析显示,本科实习护生共存在3种人格类型,弹性型(17.06%)、困扰型(45.05%)及开放型(37.88%)。回归分析显示,与开放型相比,弹性型是本科实习护生职业认同感的保护因素(P<0.01),而困扰型是其危险因素(P<0.01)。结论本科实习护生的人格类型存在弹性型、困扰型及开放型3种,困扰型表现出较低的职业认同感,值得护理管理者关注。 展开更多
关键词 实习护生 聚类分析 人格类型 职业认同
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