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Bioinspired Precision Peeling of Ultrathin Bamboo Green Cellulose Frameworks for Light Management in Optoelectronics
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作者 Yan Wang Yuan Zhang +2 位作者 Yingfeng Zuo Dawei Zhao Yiqiang Wu 《Nano-Micro Letters》 2026年第1期474-489,共16页
Cellulose frameworks have emerged as promising materials for light management due to their exceptional light-scattering capabilities and sustainable nature.Conventional biomass-derived cellulose frameworks face a fund... Cellulose frameworks have emerged as promising materials for light management due to their exceptional light-scattering capabilities and sustainable nature.Conventional biomass-derived cellulose frameworks face a fundamental trade-off between haze and transparency,coupled with impractical thicknesses(≥1 mm).Inspired by squid’s skin-peeling mechanism,this work develops a peroxyformic acid(HCOOOH)-enabled precision peeling strategy to isolate intact 10-μm-thick bamboo green(BG)frameworks—100×thinner than wood-based counterparts while achieving an unprecedented optical performance(88%haze with 80%transparency).This performance surpasses delignified biomass(transparency<40%at 1 mm)and matches engineered cellulose composites,yet requires no energy-intensive nanofibrillation.The preserved native cellulose I crystalline structure(64.76%crystallinity)and wax-coated uniaxial fibril alignment(Hermans factor:0.23)contribute to high mechanical strength(903 MPa modulus)and broadband light scattering.As a light-management layer in polycrystalline silicon solar cells,the BG framework boosts photoelectric conversion efficiency by 0.41%absolute(18.74%→19.15%),outperforming synthetic anti-reflective coatings.The work establishes a scalable,waste-to-wealth route for optical-grade cellulose materials in next-generation optoelectronics. 展开更多
关键词 Bamboo green Cellulose framework Chemical peeling Optical properties light management
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Contribution of ferroptosis and SLC7A11 to light-induced photoreceptor degeneration
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作者 Xiaoxu Huang Yumeng Zhang +9 位作者 Yuxin Jiang Tong Li Shiqi Yang Yimin Wang Bo Yu Minwen Zhou Guanran Zhang Xiaohuan Zhao Junran Sun Xiaodong Sun 《Neural Regeneration Research》 2026年第1期406-416,共11页
Progressive photoreceptor cell death is one of the main pathological features of age-related macular degeneration and eventually leads to vision loss.Ferroptosis has been demonstrated to be associated with retinal deg... Progressive photoreceptor cell death is one of the main pathological features of age-related macular degeneration and eventually leads to vision loss.Ferroptosis has been demonstrated to be associated with retinal degenerative diseases.However,the molecular mechanisms underlying ferroptosis and photoreceptor cell death in age-related macular degeneration remain largely unexplored.Bioinformatics and biochemical analyses in this study revealed xC^(–),solute carrier family 7 member 11-regulated ferroptosis as the predominant pathological process of photoreceptor cell degeneration in a light-induced dry age-related macular degeneration mouse model.This process involves the nuclear factor-erythroid factor 2-related factor 2-solute carrier family 7 member 11-glutathione peroxidase 4 signaling pathway,through which cystine depletion,iron ion accumulation,and enhanced lipid peroxidation ultimately lead to photoreceptor cell death and subsequent visual function impairment.We demonstrated that solute carrier family 7 member 11 overexpression blocked this process by inhibiting oxidative stress in vitro and in vivo.Conversely,solute carrier family 7 member 11 knockdown or the solute carrier family 7 member 11 inhibitor sulfasalazine and ferroptosis-inducing agent erastin aggravated H_(2)O_(2)-induced ferroptosis of 661W cells.These findings indicate solute carrier family 7 member 11 may be a potential therapeutic target for patients with retinal degenerative diseases including age-related macular degeneration. 展开更多
关键词 age-related macular degeneration ferroptosis light exposure damage oxidative stress pathway PHOTORECEPTOR programmed cell death solute carrier family 7 member 11(SLC7A11)
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超脉冲点阵CO_(2)激光联合DPL治疗面部凹陷性瘢痕的临床研究
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作者 薛艳 梁波 闫威 《中国美容医学》 2025年第10期121-125,共5页
目的:探讨超脉冲点阵CO_(2)激光联合窄谱强脉冲光(DPL)治疗面部凹陷性瘢痕患者的疗效。方法:选取2022年6月-2024年2月笔者医院收治的90例面部凹陷性瘢痕患者,使用随机数字表法随机分为对照组(n=45)和观察组(n=45)。对照组采用超脉冲点阵... 目的:探讨超脉冲点阵CO_(2)激光联合窄谱强脉冲光(DPL)治疗面部凹陷性瘢痕患者的疗效。方法:选取2022年6月-2024年2月笔者医院收治的90例面部凹陷性瘢痕患者,使用随机数字表法随机分为对照组(n=45)和观察组(n=45)。对照组采用超脉冲点阵CO_(2)激光治疗,观察组在对照组基础上采用DPL联合治疗。比较两组治疗效果[瘢痕美容评估及评级量表(SCAR)]、瘢痕质地改善情况[痤疮瘢痕权重评分(ECCA)、温哥华瘢痕量表(VSS)]、色素沉着(PIH)程度[PIH面积、PIH指数(PAHPI)]、皮肤外观情况[美学改善量表(GAIS)、皮肤含水量、经表皮失水率(TEWL)]以及不良反应发生情况。结果:观察组治疗效果(93.33%)显著高于对照组(77.78%)(P<0.05);治疗后,两组ECCA、VSS评分均显著下降(P<0.05),且观察组显著低于对照组(P<0.05);治疗后,两组PIH面积、PAHPI均显著减小(P<0.05),且观察组显著小于对照组(P<0.05);治疗后,两组GAIS评分、皮肤含水量均显著升高(P<0.05),且观察组显著高于对照组(P<0.05);治疗后,两组TEWL显著降低(P<0.05),且观察组显著低于对照组(P<0.05);随访期间,对照组、观察组不良反应发生率分别为11.11%和8.89%,差异无统计学意义(P>0.05)。结论:超脉冲点阵CO_(2)激光联合DPL治疗面部凹陷性瘢痕,能够显著改善瘢痕质地、减少色素沉着面积,改善皮肤外观,安全性良好。 展开更多
关键词 超脉冲点阵CO_(2)激光 窄谱强脉冲光(dpl) 面部凹陷性瘢痕 瘢痕质地 皮肤外观
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基于RF-Light GBM的分组密码算法识别方案
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作者 董秀则 杨鸿刚 +1 位作者 胡一凡 于庚辰 《北京电子科技学院学报》 2025年第2期1-10,共10页
密码算法的识别在密码分析领域中具有重要意义。目前主流分组密码算法识别方案中密文特征提取普遍基于随机性检测标准。为解决短样本识别需求以及进一步提高识别准确率,本研究提出了一种基于RF-Light GBM的分组密码体制识别方案。首先通... 密码算法的识别在密码分析领域中具有重要意义。目前主流分组密码算法识别方案中密文特征提取普遍基于随机性检测标准。为解决短样本识别需求以及进一步提高识别准确率,本研究提出了一种基于RF-Light GBM的分组密码体制识别方案。首先通过GM/T 0005-2021随机性检测标准提取密文特征,其次利用随机森林算法对高维的数据进行重要性排序和筛选,然后利用特征向量训练Light GBM算法模型构建密码算法识别分类器进行识别。实现了短样本环境下高效识别未知密文的识别需求。在两两识别实验中,与现有研究相比本方案准确率整体提升约12%;多分类实验显示准确率均在73%以上,验证了本方案在分组密码算法识别中的有效性和优势,为未来在更复杂的加密模式下进行密码算法识别提供了参考。 展开更多
关键词 分组密码 机器学习 随机性检测 密码算法识别 light GBM
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基于IWOA-LightGBM模型的矿用挖掘机发动机故障诊断研究 被引量:1
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作者 顾清华 白书宇 王丹 《矿业研究与开发》 北大核心 2025年第9期184-191,共8页
针对矿用挖掘机发动机故障类别不均衡,导致故障诊断精度不高的问题,提出了一种改进的鲸鱼算法(WOA)优化轻量级梯度提升机(LightGBM)的矿用挖掘机发动机智能故障诊断方法。首先,利用递归特征交叉验证消除法(RFECV)对采集的挖掘机发动机... 针对矿用挖掘机发动机故障类别不均衡,导致故障诊断精度不高的问题,提出了一种改进的鲸鱼算法(WOA)优化轻量级梯度提升机(LightGBM)的矿用挖掘机发动机智能故障诊断方法。首先,利用递归特征交叉验证消除法(RFECV)对采集的挖掘机发动机故障数据的特征进行提取,删除不相关的特征。其次,采用Focal-Loss改进LightGBM的损失函数,提出一种改进的WOA对LightGBM的超参数寻优,构建新的诊断模型。最后,利用某矿山挖掘机发动机故障数据进行验证,并与常见的集成模型、调优框架和诊断算法进行对比分析。结果表明:所提出的矿用挖掘机发动机故障诊断模型IWOA-LightGBM的准确率和F1分数分别为98.08%和98.53%,诊断性能较好,可为矿山机械设备的智能诊断提供参考。 展开更多
关键词 矿用挖掘机 发动机 故障诊断 递归特征交叉验证消除法 轻量级梯度提升机 鲸鱼算法
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一种基于EMD-LightGBM模型的地铁隧道盾构姿态预测方法
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作者 冷伍明 吴卓霖 +3 位作者 袁立刚 梁琳 刘涛墨 岳健 《哈尔滨工业大学学报》 北大核心 2025年第7期96-107,共12页
针对地铁隧道盾构姿态难以控制的问题,以长春某隧道工程为例,基于现场实测数据,构建了一个融合经验模态分解(empirical mode decomposition,EMD)和轻量级梯度提升机(light gradient boosting machine,LightGBM)的盾构姿态预测模型(EMD-L... 针对地铁隧道盾构姿态难以控制的问题,以长春某隧道工程为例,基于现场实测数据,构建了一个融合经验模态分解(empirical mode decomposition,EMD)和轻量级梯度提升机(light gradient boosting machine,LightGBM)的盾构姿态预测模型(EMD-LightGBM)。首先,通过特征重要性和相关性分析筛选原始数据集特征。然后,利用EMD技术将数据分解为多个平稳子序列,并组成新数据集。最后,通过该新数据集拟合训练EMD-LightGBM来实现盾构姿态的预测,并且比较了该模型与单纯的LightGBM及融合EMD的反向传播神经网络(backpropagation neural network,BPNN)的预测效果。通过预测精度和预测稳定性两种评价体系来验证EMD-LightGBM模型的优良性能。结果表明:与LightGBM和EMD-BPNN相比,EMD-LightGBM在盾构姿态偏差预测折线图中的表现最佳,其平均绝对误差(mean absolute error,E MA)和均方根误差(root mean square error,E RMS)最大分别为2.89 mm和4.13 mm,决定系数R 2最小值为0.95;同时,EMD-LightGBM的预测平均绝对误差E MA和均方误差(mean square error,E MS)的95%置信区间最大值分别为3.5 mm与25.6 mm 2,结合其预测值的绝对误差(absolute error,E A)和平方误差(square error,E S)的良好频数分布,都说明了EMD-LightGBM在预测盾构姿态时的高精度和稳定性。研究成果可为类似工程的盾构姿态控制提供一种理论方法。 展开更多
关键词 地铁隧道 盾构 姿态预测 经验模态分解 轻量级梯度提升机
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考虑天气因素的GRA-LightGBM多模式交通流量预测 被引量:1
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作者 王昕 王玥 袁柯楠 《北京信息科技大学学报(自然科学版)》 2025年第3期36-45,共10页
运用数据挖掘技术进行城市交通网络的多模式流量预测及影响因素分析,对于提高交通系统的效率和安全性,支持城市的可持续发展具有重要意义。提出一种基于轻量级梯度提升机(light gradient boosting machine, LightGBM)的多模式交通流量... 运用数据挖掘技术进行城市交通网络的多模式流量预测及影响因素分析,对于提高交通系统的效率和安全性,支持城市的可持续发展具有重要意义。提出一种基于轻量级梯度提升机(light gradient boosting machine, LightGBM)的多模式交通流量预测算法。根据历史流量数据及多种天气因素,使用灰色关联分析(grey relation analysis, GRA)和Shapley加性解释(Shapley additive explanation, SHAP)对不同交通模式下的天气特征进行筛选,完成城市交通网络中铁路、公交车等6种模式交通流量的鲁棒性预测。仿真试验结果显示,除民航外,GRA-LightGBM组合模型的预测精度在其余5种交通模式的流量预测中均优于极端梯度提升(extreme gradient boosting,XGBoost)模型、支持向量回归(support vector regression, SVR)模型和差分自回归移动平均(autoregressive integrated moving average, ARIMA)模型,表明GRA-LightGBM组合模型兼具时序感知和天气特征融合能力。 展开更多
关键词 多模式 数据平滑 灰色关联分析 轻量级梯度提升机 交通流量预测
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LightDiffu-DCE:基于光照强度扩散的低光照图像增强
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作者 闫光辉 吴佰靖 马龙 《光学精密工程》 北大核心 2025年第7期1114-1129,共16页
针对低光照图像中不同光源的光照强度分布不均,在图像增强时造成轮廓特征丢失及效果不自然的问题,提出一种基于光照强度扩散的低光照图像增强方法(Light Diffusion based Zero-DCE Image Enhancement Algorithm,LightDiffu-DCE)。为增... 针对低光照图像中不同光源的光照强度分布不均,在图像增强时造成轮廓特征丢失及效果不自然的问题,提出一种基于光照强度扩散的低光照图像增强方法(Light Diffusion based Zero-DCE Image Enhancement Algorithm,LightDiffu-DCE)。为增强模型的泛化能力,提出了基于光源光照强度建模的扩散模型,以生成不同光照强度的训练数据集。设计了边缘特征融合的深度曲线估计网络,能够提取更丰富的低光照图像的多尺度轮廓和细节特征,提升对光照强度估计的准确性。为恢复出光照更加自然的图像,融合大气光估计来计算不同图像区域的光照强度,实现了对光增强曲线和光增强系数的动态微调。在无参考数据集ExDark和有参考数据集LOL上,使用6种评价指标进行实验分析。实验结果表明,相较于基准方法,LightDiffu-DCE在ExDark上的无参考评价指标NIQE,PIQE和RISQ上分别提升了约8.35%,6.20%和21.83%,在LOL数据集上的有参考评价指标PSNR,SSIM和RMSE提升了约12.12%,4.76%和49.89%。该方法可以有效增强低光照图像,且恢复出的低光照图像轮廓更加清晰,色彩鲜明且效果更自然。 展开更多
关键词 计算机视觉 扩散模型 低光照增强 边缘特征 深度曲线估计网络
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Obtaining 2D Soil Resistance Profiles from the Integration of Electrical Resistivity Data and Standard Penetration Test (SPT) and Light Dynamic Penetrometer (DPL) Resistance Tests—Applications in Mass Movements Studies
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作者 Cassiano Antonio Bortolozo Tatiana Sussel Gonçalves Mendes +10 位作者 Mariana Ferreira Benessiuti Motta Silvio Jorge Coelho Simões Tristan Pryer Daniel Metodiev Marcio Roberto Magalhães de Andrade Maiconn Vinicius de Moraes Danielle Silva de Paula Nélio José Bastos Luana Albertani Pampuch Rodolfo Moreda Mendes Marcio Augusto Ernesto de Moraes 《International Journal of Geosciences》 2023年第9期840-854,共15页
In Brazil and various regions globally, the initiation of landslides is frequently associated with rainfall;yet the spatial arrangement of geological structures and stratification considerably influences landslide occ... In Brazil and various regions globally, the initiation of landslides is frequently associated with rainfall;yet the spatial arrangement of geological structures and stratification considerably influences landslide occurrences. The multifaceted nature of these influences makes the surveillance of mass movements a highly intricate task, requiring an understanding of numerous interdependent variables. Recent years have seen an emergence in scholarly research aimed at integrating geophysical and geotechnical methodologies. The conjoint examination of geophysical and geotechnical data offers an enhanced perspective into subsurface structures. Within this work, a methodology is proposed for the synchronous analysis of electrical resistivity geophysical data and geotechnical data, specifically those extracted from the Light Dynamic Penetrometer (DPL) and Standard Penetration Test (SPT). This study involved a linear fitting process to correlate resistivity with N10/SPT N-values from DPL/SPT soundings, culminating in a 2D profile of N10/SPT N-values predicated on electrical profiles. The findings of this research furnish invaluable insights into slope stability by allowing for a two-dimensional representation of penetration resistance properties. Through the synthesis of geophysical and geotechnical data, this project aims to augment the comprehension of subsurface conditions, with potential implications for refining landslide risk evaluations. This endeavor offers insight into the formulation of more effective and precise slope management protocols and disaster prevention strategies. 展开更多
关键词 GEOPHYSICS Geotechnical Data Electrical Resistivity Method Standard Penetration Test (SPT) light Dynamic Penetrometer (dpl) Mass Movements
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氨甲环酸口服联合DPL治疗面部中重度黄褐斑的疗效探究
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作者 王珏祯 赵玢 +1 位作者 邵俊 耿易金 《中国美容医学》 2025年第8期121-124,共4页
目的:观察口服氨甲环酸(Tranexamic acid,TXA)联合精准脉冲光(Delicate pulse light,DPL)治疗面部中重度黄褐斑的美学效果。方法:选取2020年7月-2023年7月于西安娇唐医疗美容医院美容皮肤科接受治疗的118例黄褐斑患者,根据不同治疗方法... 目的:观察口服氨甲环酸(Tranexamic acid,TXA)联合精准脉冲光(Delicate pulse light,DPL)治疗面部中重度黄褐斑的美学效果。方法:选取2020年7月-2023年7月于西安娇唐医疗美容医院美容皮肤科接受治疗的118例黄褐斑患者,根据不同治疗方法,分为DPL组(n=57,DPL治疗)和联合组(n=61,TXA联合DPL治疗)。比较两组治疗前后黄褐斑皮损面积与严重程度(MASI)评分、疗效、皮肤生理参数、不良反应发生率及复发率。结果:治疗后,DPL组的MASI评分与联合组比较,联合组优于DPL组(P<0.05);联合组总有效率高于DPL组(P<0.05);DPL组和联合组经皮水分丢失水平均下降,且联合组低于DPL组(P<0.05),两组表皮油脂含量、角质层含水量均升高,且联合组高于DPL组(P<0.05);两组总不良反应发生率及复发率,差异无统计学意义(P>0.05)。结论:TXA联合DPL治疗面部中重度黄褐斑的美学效果良好,能减轻色素沉着,修复皮肤屏障,改善皮肤水油平衡,安全性高。 展开更多
关键词 氨甲环酸(TXA) 精准脉冲光(dpl) 黄褐斑 皮肤生理参数 皮肤屏障 美学效果
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基于DDPM-LightGBM的电力CPS多标签不平衡虚假数据注入攻击的检测 被引量:1
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作者 李俊颉 高莲 +3 位作者 李鹏 张璇 杨家全 苏适 《昆明理工大学学报(自然科学版)》 北大核心 2025年第3期49-57,共9页
针对电力信息-物理系统(Cyber-Physical Systems,CPS)数据不平衡导致的多标签虚假数据注入攻击(False Data Injection Attack,FDIA)检测模型精度不高以及数据量大导致检测时间长的问题,提出了一种基于去噪扩散概率模型(Denoising Diffus... 针对电力信息-物理系统(Cyber-Physical Systems,CPS)数据不平衡导致的多标签虚假数据注入攻击(False Data Injection Attack,FDIA)检测模型精度不高以及数据量大导致检测时间长的问题,提出了一种基于去噪扩散概率模型(Denoising Diffusion Probabilistic Models,DDPM)和轻量梯度提升机(Light Gradient Boosting Machine,LightGBM)的FDIA检测模型.利用DDPM模型来生成数据集中不同标签的少数类攻击数据样本,解决数据集平衡问题,通过余弦相似性来对生成的数据的质量进行评价,从而判断数据生成的质量;采用LightGBM算法,通过直方图技术、梯度单边采样技术和互斥特征捆绑技术简化数据和模型复杂度,提升检测速度和精度.以密西西比州立大学和橡树岭国家实验室提供的电力CPS多标签数据集进行仿真实验,结果表明本模型能够生成高质量的攻击数据,解决数据不平衡问题,明显提升了对多标签FDIA的检测率. 展开更多
关键词 虚假数据注入攻击 去噪扩散概率模型 不平衡数据 轻量梯度提升机
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Low-light image enhancement for UAVs guided by a light weighted map 被引量:1
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作者 BAI Xiaotong WANG Dianwei +2 位作者 FANG Jie LI Yuanqing XU Zhijie 《Optoelectronics Letters》 2025年第6期348-353,共6页
The unmanned aerial vehicle(UAV)images captured under low-light conditions are often suffering from noise and uneven illumination.To address these issues,we propose a low-light image enhancement algorithm for UAV imag... The unmanned aerial vehicle(UAV)images captured under low-light conditions are often suffering from noise and uneven illumination.To address these issues,we propose a low-light image enhancement algorithm for UAV images,which is inspired by the Retinex theory and guided by a light weighted map.Firstly,we propose a new network for reflectance component processing to suppress the noise in images.Secondly,we construct an illumination enhancement module that uses a light weighted map to guide the enhancement process.Finally,the processed reflectance and illumination components are recombined to obtain the enhancement results.Experimental results show that our method can suppress the noise in images while enhancing image brightness,and prevent over enhancement in bright regions.Code and data are available at https://gitee.com/baixiaotong2/uav-images.git. 展开更多
关键词 unmanned aerial vehicle retinex theory light weighted map reflectance component processing illumination enhancement module noise suppression unmanned aerial vehicle uav images low light image enhancement
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Efficient chlorination reaction of Pt/RuO_(2)/g-C_(3)N_(4)under visible light irradiation for simultaneous removal of ammonia and bacteria from mariculture wastewater 被引量:1
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作者 Yizhan Zhang Min Zhao +2 位作者 Yida Huang Yan-Ling Hu Lei Wang 《Journal of Environmental Sciences》 2025年第4期490-502,共13页
The removal of ammonia nitrogen(NH_(4)^(+)-N)and bacteria from aquaculture wastewater holds paramount ecological and production significance.In this study,Pt/RuO_(2)/g-C_(3)N_(4)photocatalysts were prepared by deposit... The removal of ammonia nitrogen(NH_(4)^(+)-N)and bacteria from aquaculture wastewater holds paramount ecological and production significance.In this study,Pt/RuO_(2)/g-C_(3)N_(4)photocatalysts were prepared by depositing Pt and RuO_(2)particles onto g-C_(3)N_(4).The physicochemical properties of photocatalysts were explored by X-ray photoelectron spectroscopy(XPS),scanning electron microscopy(SEM),X-ray diffraction(XRD),and UV–vis diffuse reflectance spectrometer(UV–vis DRS).The photocatalysts were then applied to the removal of both NH_(4)^(+)-N and bacteria from simulated mariculture wastewater.The results clarified that the removals of both NH_(4)^(+)-N and bacteria were in the sequence of g-C_(3)N_(4)<RuO_(2)/g-C_(3)N_(4)<Pt/g-C_(3)N_(4)<Pt/RuO_(2)/g-C_(3)N_(4).This magnificent photocatalytic ability of Pt/RuO_(2)/g-C_(3)N_(4)can be interpreted by the transfer of holes from g-C_(3)N_(4)to RuO_(2)to facilitate the in situ generation of HClO from Cl^(−)in wastewater,while Pt extracts photogenerated electrons for H_(2)formation to enhance the reaction.The removal of NH_(4)^(+)-N and disinfection effect were more pronounced in simulated seawater than in purewater.The removal efficiency ofNH_(4)^(+)-N increases with an increase in pH of wastewater,while the bactericidal effect was more significant under a lower pH in a pH range of 6–9.In actual seawater aquaculture wastewater,Pt/RuO_(2)/g-C_(3)N_(4)still exhibits effective removal efficiency of NH_(4)^(+)-N and bactericidal performance under sunlight.This study provides an alternative avenue for removement of NH_(4)^(+)-N and bacteria from saline waters under sunlight. 展开更多
关键词 PHOTOCATALYSIS Mariculture wastewater Ammonia nitrogen Visible light irradiation Microbial inactivation
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A Low Light Image Enhancement Method Based on Dehazing Physical Model 被引量:1
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作者 Wencheng Wang Baoxin Yin +2 位作者 Lei Li Lun Li Hongtao Liu 《Computer Modeling in Engineering & Sciences》 2025年第5期1595-1616,共22页
In low-light environments,captured images often exhibit issues such as insufficient clarity and detail loss,which significantly degrade the accuracy of subsequent target recognition tasks.To tackle these challenges,th... In low-light environments,captured images often exhibit issues such as insufficient clarity and detail loss,which significantly degrade the accuracy of subsequent target recognition tasks.To tackle these challenges,this study presents a novel low-light image enhancement algorithm that leverages virtual hazy image generation through dehazing models based on statistical analysis.The proposed algorithm initiates the enhancement process by transforming the low-light image into a virtual hazy image,followed by image segmentation using a quadtree method.To improve the accuracy and robustness of atmospheric light estimation,the algorithm incorporates a genetic algorithm to optimize the quadtree-based estimation of atmospheric light regions.Additionally,this method employs an adaptive window adjustment mechanism to derive the dark channel prior image,which is subsequently refined using morphological operations and guided filtering.The final enhanced image is reconstructed through the hazy image degradation model.Extensive experimental evaluations across multiple datasets verify the superiority of the designed framework,achieving a peak signal-to-noise ratio(PSNR)of 17.09 and a structural similarity index(SSIM)of 0.74.These results indicate that the proposed algorithm not only effectively enhances image contrast and brightness but also outperforms traditional methods in terms of subjective and objective evaluation metrics. 展开更多
关键词 Dark channel prior quadtree decomposition genetic algorithm atmospheric light image enhancement
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基于Light-GBM算法的地震动显著持时预测模型
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作者 崔铭钊 公茂盛 +3 位作者 左占宣 赵一男 贾佳 张孔 《振动与冲击》 北大核心 2025年第16期185-192,共8页
地震动持时对地震结构反应有显著影响,因此对考虑持时效应的工程结构抗震设计和区域地震危险性分析具有重要意义。该研究提出了一种基于轻量级梯度提升机(light gradient boosting machine,Light-GBM)算法的地震动显著持时预测模型,基于... 地震动持时对地震结构反应有显著影响,因此对考虑持时效应的工程结构抗震设计和区域地震危险性分析具有重要意义。该研究提出了一种基于轻量级梯度提升机(light gradient boosting machine,Light-GBM)算法的地震动显著持时预测模型,基于NGA-West2数据库,筛选了其中15541条地震动记录并计算其显著持时,随后通过特征重要性筛选输入参数并利用贝叶斯优化方法调整模型超参数,最终构建了地震动显著持时的预测模型,并与其他传统模型和深度学习模型对比,从而对模型的准确性和鲁棒性进行验证。结果表明,所建立的地震动显著持时预测模型具有良好预测性能、极高的计算效率和通用性,结果可供地震动持时预测及地震危险性分析等工作参考。 展开更多
关键词 地震动持时 预测模型 轻量级梯度提升机(light-GBM)算法 显著持时 机器学习
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面向肺部肿瘤分类的跨模态Light-3Dformer模型
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作者 周涛 牛玉霞 +2 位作者 叶鑫宇 刘隆 陆惠玲 《电子学报》 北大核心 2025年第3期951-961,共11页
基于深度学习的三维多模态正电子发射型断层扫描/计算机断层扫描(Positron Emission Tomography/Computed Tomography,PET/CT)肺部肿瘤识别是一个重要的研究方向.肺部肿瘤病灶的空间形状不规则、与周围组织边界模糊,导致模型难以充分提... 基于深度学习的三维多模态正电子发射型断层扫描/计算机断层扫描(Positron Emission Tomography/Computed Tomography,PET/CT)肺部肿瘤识别是一个重要的研究方向.肺部肿瘤病灶的空间形状不规则、与周围组织边界模糊,导致模型难以充分提取肿瘤特征,且模型在三维任务中需要较高的计算复杂度.针对上述问题,本文提出一种跨模态Light-3Dformer的三维肺部肿瘤识别模型.本文的主要创新工作有以下几个方面.首先,采用主、辅网络结构,其中主干网络提取PET/CT图像特征,辅助网络提取PET图像和CT图像特征,并采用轻量化跨模态协同注意力实现多模态特征增强和交互式学习.其次,设计Light-3Dformer模块,在该模块中,将Transformer的2次矩阵乘法操作更新为全局注意力机制Lightformer的线性元素乘法操作;设计级联Lightformer结构,其输出特征图和最初的输入特征图融合,通过并行和融合更多的深浅层特征,可以实现轻量化和提取丰富的梯度信息;设计无参数的注意力,该机制能从通道、空间和断层3个方面增强肺部肿瘤特征提取能力.再次,设计轻量化跨模态协同注意力模块(Light Cross-modal Collaborative Attention Module,LCCAM),该模块能充分学习三维多模态影像的跨模态优势信息,对深浅层特征进行交互式学习.最后,进行消融实验和对比实验,在自建的肺部肿瘤三维多模态数据集中,本文模型在计算量和运行时间最优的前提下,准确率和曲线下面积(Area Under the Curve,AUC)值分别达到90.19%和89.81%,与3D-SwinTransformer-S模型相比,参数量降低117倍,计算量降低400倍.实验结果表明:本文模型能更好地提取肺部肿瘤病灶的多模态信息,这为深度学习三维模型轻量化和多模态交互提供了新思路. 展开更多
关键词 肺部肿瘤 多模态图像 Transformer light-3Dformer 轻量化跨模态协同注意力
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Development of Palygorskite-CaIn_(2)S_(4) composite for rapid Cr(Ⅵ) reduction under visible light 被引量:1
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作者 Yuanyuan Wang Shijun Jia +3 位作者 Shiqiang Ding Wenyan Zhang Rui Shu Yingfei Hu 《Journal of Environmental Sciences》 2025年第10期562-575,共14页
Using natural minerals to eliminate harmful Cr(Ⅵ)under sustainable sunshine has significant potential.Herein,Palygorskite nanorods were utilized as carriers for the in-situ synthesis of CaIn_(2)S_(4) photocatalysts t... Using natural minerals to eliminate harmful Cr(Ⅵ)under sustainable sunshine has significant potential.Herein,Palygorskite nanorods were utilized as carriers for the in-situ synthesis of CaIn_(2)S_(4) photocatalysts through a simple one-pot thermal process,enabling the efficient reduction of Cr(Ⅵ).With a Palygorskite to CaIn_(2)S_(4) mass ratio of 5%,the conversion rate of Cr(Ⅵ)reached 98%after 60min of visible-light exposure,with a remarkable reaction rate of 0.0633 min^(-1).The effective integration of CaIn_(2)S_(4) with Palygorskite led to a more uniform dispersion of CaIn_(2)S_(4),exposing more reactive sites.Moreover,the establishment of a heterojunction between CaIn_(2)S_(4) and Palygorskite facilitated the transport of photogenerated electrons from CaIn_(2)S_(4),enhancing the efficiency of charge separation.These factors contribute to the improved photocatalytic performance.Additionally,the developed composite photocatalysts demonstrated excellent stability under light exposure and could be reused efficiently.Trapping tests on active substances revealed that e-played key roles in the Cr(Ⅵ)reduction.This research suggests the potential of using natural minerals to fabricate composite photocatalysts capable of effectively removing pollutants from the environment using solar energy. 展开更多
关键词 Cr(Ⅵ)reduction Visible light PALYGORSKITE CaIn_(2)S_(4)
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Visible Light-Promoted Aerobic Oxo-azidation of Alkenyl Silanes
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作者 Tan Yan Ying Jiale +1 位作者 Yu Bing Lu Zhan 《有机化学》 北大核心 2025年第5期1684-1690,共7页
A visible-light-enabled method for the synthesis ofα-azidoketones has been developed via oxo-azidation of alkenyl silanes with trimethylsilylazide and molecular oxygen under mild conditions.The reaction could be carr... A visible-light-enabled method for the synthesis ofα-azidoketones has been developed via oxo-azidation of alkenyl silanes with trimethylsilylazide and molecular oxygen under mild conditions.The reaction could be carried out in gram scale.Various radical sources,including trifluoromethyl radical,thiocyanate radical,bromide radical,chlorine radical could partici-pate effectively instead of azide radical in the reaction. 展开更多
关键词 visible light catalysis aerobic oxidation alkenyl silanes organic azides
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WOA优化LightGBM在火成岩测井岩性识别中的应用 被引量:2
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作者 冯欢 张国强 +3 位作者 曹军 任宏 万文春 刘迪仁 《地球物理学进展》 北大核心 2025年第1期230-242,共13页
渤海南部莱州湾地区的火成岩岩性复杂多变,常规测井交会图识别效果差.为提升该地区火成岩岩性识别精度,结合全局优化能力强的鲸鱼优化算法(WOA)和高效的轻量级梯度提升机(LightGBM),提出了基于WOA-LightGBM的火成岩测井岩性识别方法.首... 渤海南部莱州湾地区的火成岩岩性复杂多变,常规测井交会图识别效果差.为提升该地区火成岩岩性识别精度,结合全局优化能力强的鲸鱼优化算法(WOA)和高效的轻量级梯度提升机(LightGBM),提出了基于WOA-LightGBM的火成岩测井岩性识别方法.首先,通过分析岩性的测井响应特征,选择岩心和薄片等地质资料完整、常规九条测井曲线齐全的测井数据作为样本集;然后将样本集输入到WOA-LightGBM、WOA-AdaBoost、WOA-SVM、LightGBM、AdaBoost、SVM六种模型中进行识别,并将识别结果进行对比验证;最后将识别模型应用于15口井中.研究结果表明:当鲸鱼种群为50时,最佳超参数下的WOA-LightGBM模型的识别精度最高、泛化能力最好,在样本集中识别准确率达91.62%,ROC-AUC为0.9676,实例井中整体解释符合率达85%.WOA-LightGBM可作为利用测井曲线智能识别渤海火成岩岩性的有效方法,并为其他类似区块的火成岩岩性识别提供参考. 展开更多
关键词 莱州湾 火成岩 测井岩性识别 轻量级梯度提升机 超参数 鲸鱼优化算法
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Simulation of light environment in a serrated photovoltaic greenhouse and optimization of daylighting roofs based on Design Builder
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作者 LIU Jian WU Xuyong +2 位作者 WANG Baolong WU Qingsen TIAN Libo 《农业工程学报》 北大核心 2025年第7期211-221,共11页
In the tropical regions represented by Hainan,there are abundant solar and thermal resources,and it is relatively suitable for the construction of photovoltaic greenhouse(PVG).However,the construction of PVG still rel... In the tropical regions represented by Hainan,there are abundant solar and thermal resources,and it is relatively suitable for the construction of photovoltaic greenhouse(PVG).However,the construction of PVG still relies mainly on experience and is incapable of quantifying the balance between the photovoltaic(PV)generation and the light requirements for agricultural production.As a result,actual PVGs are primarily PV-based,without carefully considering the needs of agricultural daylighting.To quantify the influence of the design parameters of PVGs and the layout of PV panels on the internal daylighting of serrated PVGs,and to optimize the daylighting design of the roof,this paper utilizes the Design Builder software to establish gradient models for a multi-span serrated-type PVG in tropical regions.Gradient models were established in terms of aspects,namely span,width of longitudinal/transverse daylighting strip,height,roof angle,and photovoltaic panel coverage rate(PCR).Daylighting in the greenhouse of each gradient model was simulated,and with the annual average daily light integral(A_(DLI))and distribution uniformity(DU)as evaluation indicators,the influence of various design parameters on the daylighting inside the greenhouse was quantified.The result reveals that:(1)PCR is the decisive indicator for daylighting in the PVG,and a function between PCR and the A_(DLI) is derived as A_(DLI)=-15.5 PCR+16.841;(2)Increasing the width of longitudinal daylighting strip significantly improves the A_(DLI) and enhances DU while increasing the span has a noticeable effect on improving A_(DLI) but does not significantly enhance DU;(3)Increasing the eave height without changing PCR does not enhance A_(DLI) but effectively improves DU;increasing the transverse daylighting strip and adjusting the roof angle hardly improves A_(DLI).In summary,it is recommended that the optimal span for PVGs in tropical regions be set within the range of 6.5-8.0m,and the eave height be set within the range of 2.5-3.5m.Preferably,the longitudinal daylighting strip with a width ranging from 0.5-0.8m should be installed.Based on the above relationship function,the PCR can be calculated according to the appropriate light demand for the cultivated crops.The daylighting design theory proposed in this paper can provide a theoretical basis and reference for the healthy development of the PV industry in tropical regions. 展开更多
关键词 photovoltaic greenhouse annual average daily light integral greenhouse design parameters DAYlightING tropical regions
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