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Tailoring a Back-Contact Barrier for a Self-Powered Broadband Kesterite Photodetector With Ultralow Dark Current Enabling Ultra-Weak-Light Detection
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作者 Qianfeng Wu Chuanhao Li +7 位作者 Shuo Chen Zhenghua Su Muhammad Abbas Chao Chen Qianqian Lin Jingting Luo Liming Ding Guangxing Liang 《Carbon Energy》 2025年第5期35-44,共10页
Visible and near-infrared photodetectors are widely used in intelligent driving,health monitoring,and other fields.However,the application of photodetectors in the near-infrared region is significantly impacted by hig... Visible and near-infrared photodetectors are widely used in intelligent driving,health monitoring,and other fields.However,the application of photodetectors in the near-infrared region is significantly impacted by high dark current,which can greatly reduce their performance and sensitivity,thereby limiting their effectiveness in certain applications.In this work,the introduction of a C60 back interface layer successfully mitigated back interface reactions to decrease the thickness of the Mo(S,Se)_(2)layer,tailoring the back-contact barrier and preventing reverse charge injection,resulting in a kesterite photodetector with an ultralow dark current density of 5.2×10^(-9)mA/cm^(2)and ultra-weak-light detection at levels as low as 25 pW/cm^(2).Besides,under a self-powered operation,it demonstrates outstanding performance,achieving a peak responsivity of 0.68 A/W,a wide response range spanning from 300 to 1600 nm,and an impressive detectivity of 5.27×10^(14)Jones.In addition,it offers exceptionally rapid response times,with rise and decay times of 70 and 650 ns,respectively.This research offers important insights for developing high-performance self-powered near-infrared photodetectors that have high responsivity,rapid response times,and ultralow dark current. 展开更多
关键词 DETECTIVITY KESTERITE PHOTODETECTOR thin film weak light detection
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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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Dynamical Dark Energy in Light of Cosmic Distance Measurements.Ⅱ.A Study Using Current Observations 被引量:1
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作者 Xiaoma Wang Gan Gu +2 位作者 Xiaoyong Mu Shuo Yuan Gong-Bo Zhao 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2024年第6期15-20,共6页
We extract key information on dark energy from current observations of BAO,OHD and H_(0),and find hints of dynamical behavior of dark energy.In particular,a dynamical dark energy model whose equation of state crosses-... We extract key information on dark energy from current observations of BAO,OHD and H_(0),and find hints of dynamical behavior of dark energy.In particular,a dynamical dark energy model whose equation of state crosses-1 is favored by observations.We also find that the Universe has started accelerating at a lower redshift than expected. 展开更多
关键词 COSMOLOGY (cosmology:)dark energy cosmology:observations
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基于DarkEnv-YOLO的弱光目标检测
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作者 王银 候鑫杰 +1 位作者 谢刚 赵志诚 《计算机仿真》 2025年第4期336-341,共6页
针对弱光环境下目标检测性能不足的问题,提出一种改进YOLOv8的弱光环境目标检测算法DarkEnv-YOLO。首先,使用Zero-DCE++增强算法对图像预增强处理,加强目标在弱光环境下的可识别性。其次,在主干网络C2F模块Bottleneck中使用Rep Ghost模... 针对弱光环境下目标检测性能不足的问题,提出一种改进YOLOv8的弱光环境目标检测算法DarkEnv-YOLO。首先,使用Zero-DCE++增强算法对图像预增强处理,加强目标在弱光环境下的可识别性。其次,在主干网络C2F模块Bottleneck中使用Rep Ghost模块取代原网络中的部分卷积,简化网络模型提高检测速度。同时在颈部网络融合Sim AM无参注意力机制,改善卷积网络的表征能力提高检测精度。最后,使用Wise-Io U边界框回归损失函数,考虑不同图像之间权重分配从而提高检测任务的性能。实验结果表明,相较于YOLOv8在ExDark数据集上检测速度增加了4FPS,mAP精度提升了2.4%,改进后的网络能够有效地提高在弱光场景下目标检测的性能。 展开更多
关键词 目标检测 弱光环境 深度学习
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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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基于IWOA-LightGBM模型的矿用挖掘机发动机故障诊断研究
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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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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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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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Dynamical Dark Energy in Light of Cosmic Distance Measurements.Ⅰ.A Demonstration Using Simulated Datasets
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作者 Gan Gu Xiaoma Wang +2 位作者 Xiaoyong Mu Shuo Yuan Gong-Bo Zhao 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2024年第6期7-14,共8页
We develop methods to extract key dark energy information from cosmic distance measurements including the BAO scales and supernova(SN) luminosity distances.Demonstrated using simulated data sets of the complete DESI,L... We develop methods to extract key dark energy information from cosmic distance measurements including the BAO scales and supernova(SN) luminosity distances.Demonstrated using simulated data sets of the complete DESI,LSST and Roman surveys designed for BAO and SN distance measurements,we show that using our method,the dynamical behavior of the energy,pressure,equation of state(with its time derivative) of dark energy and the cosmic deceleration function can all be accurately recovered from high-quality data,which allows for robust diagnostic tests for dark energy models. 展开更多
关键词 (cosmology:)dark energy (cosmology:)large scale structure of universe (cosmology:)cosmic background radiation (cosmology:)cosmological parameters
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Extinction of Light in the Galactic Halo: First Observational Evidence of the Interaction of Light and Dark Matter
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作者 Charles H. McGruder III 《Journal of Modern Physics》 2024年第8期1144-1198,共55页
We study the distribution of quasars on the celestial sphere according to ground-based SDSS and space-based WISE and Gaia observations. All distributions as a function of galactic latitude, b, exhibit a decrease in qu... We study the distribution of quasars on the celestial sphere according to ground-based SDSS and space-based WISE and Gaia observations. All distributions as a function of galactic latitude, b, exhibit a decrease in quasar frequency well outside the dust in and near the galactic plane. We prove that the observed decrease in quasar frequency at high galactic latitudes is not accompanied by reddening, meaning that it can not be caused by dust. The scattering of light by the circumgalactic gas is negligible because the Thomson scattering cross section is very small. We conclude the observed scattering of light must be caused by dark matter in the galactic halo. We determine the mass and charge of dark matter particles. If the dark matter particle is a fermion its mass, mDMand charge eDM=δe, where e is the elementary charge are: mDM=3.2×10−2eV and δ=3.856×10−5. If however the dark matter particle is spinless then: mDM=0.511eV and δ=2.132×10−4. These values for the charge of a dark matter particle are orders of magnitude higher than the upper limit of the neutrino charge according to laboratory experiments. Consequently, dark matter particles are not charged neutrinos. Since dark matter particles are charged, they must emit and absorb electromagnetic radiation. However, PDM~δ2, or: PDM~1.487×10−9Pe, where Peis the power output of a single electron. 展开更多
关键词 Milky Way dark Matter Halo (1049)
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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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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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Design of a LYSO crystal electromagnetic calorimeter for dark photon detection in the DarkSHINE experiment
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作者 Zhi-Yu Zhao Qi-Bin Liu +24 位作者 Ji-Yuan Chen Jing Chen Jun-Feng Chen Xiang Chen Chang-Bo Fu Jun Guo Kim Siang Khaw Liang Li Shu Li Dan-Ning Liu Kun Liu Si-Yuan Song Tong Sun Jian-Nan Tang Yu-Feng Wang Zhen Wang Wei-Hao Wu Hai-Jun Yang Yu-Ming Lin Rui Yuan Yu-Lei Zhang Yun-Long Zhang Bai-Hong Zhou Xu-Liang Zhu Yi-Fan Zhu 《Nuclear Science and Techniques》 2025年第3期69-84,共16页
This paper presents the design and optimization of a lutetium yttrium oxyorthosilicate(LYSO)crystal electromagnetic calorimeter(ECAL)for the DarkSHINE experiment,which aims to identify dark photons as potential mediat... This paper presents the design and optimization of a lutetium yttrium oxyorthosilicate(LYSO)crystal electromagnetic calorimeter(ECAL)for the DarkSHINE experiment,which aims to identify dark photons as potential mediators of dark forces.The ECAL design was evaluated through comprehensive simulations,focusing on optimizing dimensions,material selection,energy distribution,and energy resolution.The configuration consisted of 21×21×11 LYSO crystals,each measuring 2.5 cm×2.5 cm×4 cm,arranged in a staggered layout to enhance signal detection efficiency.A 4 GeV energy dynamic range was established to ensure accurate energy measurements without saturation,which is essential for background rejection and signal identification.A detailed digitization model was developed to simulate scintillation,silicon photomultiplier,and analog-to-digital converter behaviors,providing a realistic representation of the detector's performance.Additionally,the study assessed radiation damage in the ECAL region,emphasizing the importance of using radiation-resistant scintillators and silicon sensors. 展开更多
关键词 Electromagnetic calorimeter LYSO Scintillator detector light dark matter dark photon
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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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Complex Field Theory: A Unifying Framework for Dark Matter and Dark Energy with the Material Universe
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作者 Hossin Abdeldayem 《Journal of Modern Physics》 2025年第1期140-151,共12页
Complex Field Theory (CFT) proposes that dark matter (DM) and dark energy (DE) are pervasive, complex fields of charged complex masses of equally positive and negative complex charges, respectively. It proposes that e... Complex Field Theory (CFT) proposes that dark matter (DM) and dark energy (DE) are pervasive, complex fields of charged complex masses of equally positive and negative complex charges, respectively. It proposes that each material object, including living creatures, is concomitant with a fraction of the charged complex masses of DM and DE in proportion to its mass. This perception provides new insights into the physics of nature and its constituents from subatomic to cosmic scales. This complex nature of DM and DE explains our inability to see DM or harvest DE for the last several decades. The positive complex DM is responsible for preserving the integrity of galaxies and all material systems. The negative complex charged DE induces a positive repelling force with the positively charged DM and contributes to the universe’s expansion. Both fields are Lorentz invariants in all directions and entangle the whole universe. The paper uses CFT to investigate zero-point energy, particle-wave duality, relativistic mass increase, and entanglement phenomenon and unifies Coulomb’s and Newton’s laws. The paper also verifies the existence of tachyons and explains the spooky action of quantum mechanics at a distance. The paper encourages further research into how CFT might resolve several physical mysteries in physics. 展开更多
关键词 dark Energy dark Matter Complex Field Theory Entanglement Zero-Point Energy Particle-Wave Duality Gravity Unification of Coulomb’s and Newton’s Laws TACHYONS Spooky Action Effect
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A Dark Energy Hypothesis III
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作者 James Togeas 《Journal of High Energy Physics, Gravitation and Cosmology》 2025年第1期39-44,共6页
The subject is the thermodynamics of dark energy. Thermodynamically, the ratio of dark energy to CMR temperature has the units of entropy, has a well-defined numerical value at every moment of cosmological history, an... The subject is the thermodynamics of dark energy. Thermodynamically, the ratio of dark energy to CMR temperature has the units of entropy, has a well-defined numerical value at every moment of cosmological history, and increases in time monotonically without limit. The proposal is that it is the cosmological entropy, aka dark entropy. Discussion compares it to other notions of entropy. Dark entropy is a necessary prelude to DEH IV, which is about the thermodynamics of dark matter. 展开更多
关键词 dark Energy ENTROPY Second Law
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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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A Dark Energy Hypothesis IV
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作者 James Togeas 《Journal of High Energy Physics, Gravitation and Cosmology》 2025年第1期45-55,共11页
The subject is the thermodynamics of dark matter, the Helmholtz free energy. The method of fluctuations leads to an estimate of the mass of a dark matter particle. The picture that emerges is that of a small-mass, deg... The subject is the thermodynamics of dark matter, the Helmholtz free energy. The method of fluctuations leads to an estimate of the mass of a dark matter particle. The picture that emerges is that of a small-mass, degenerate, spinless boson. Contour integration produces dark matter equations of state. 展开更多
关键词 dark Matter Helmholtz Free Energy FLUCTUATIONS FUGACITY BE Gas and Condensate
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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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