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The world's brightest flashlight
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作者 张玉敏 《疯狂英语(新读写)》 2025年第3期54-55,77,78,共4页
The brightest flashlight named Imalent MS32 is capable of outputting up to 200,000 lumens of light,more than any other commercially available flashlight.Imagine having the ability to turn night into day in the palm of... The brightest flashlight named Imalent MS32 is capable of outputting up to 200,000 lumens of light,more than any other commercially available flashlight.Imagine having the ability to turn night into day in the palm of yourself and you kind of get a sense of what using the world's brightest flashlight feels and looks like.The Imalent MS32 is so incredibly powerful that the only other flashlight you can even compare it to is the Imalent MS18,the previous holder of the title of“world's brightest flashlight”.And that one was virtually half as powerful as the MS32,with a peak brightness of just 100,000 lumens.The LED‑powered light beam of the MS32 can reach as far as 1,618 meters and is the equivalent of 100 car lights in terms of brightness. 展开更多
关键词 Imalent MS lumens car lights imalent ms worlds brightest flashlight light beam
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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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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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Behind the scenes:the roles of light signaling in stomatal movements
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作者 Kangyou Zhu Qianru Guo +12 位作者 Yulin Chen Xin Bu Jiarong Yan Ying Zhang Xiujie Wang Xin Sun Xuefeng Zhang Golam Jalal Ahammed Zhiming Wu Yufeng Liu Mingfang Qi Tianlai Li Feng Wang 《Horticultural Plant Journal》 2025年第5期1711-1726,共16页
Stomata are tiny pores on the plant leaf surface that regulate the exchange of water and gases between the plant and the external environment.They are crucial for photosynthesis,water use efficiency(WUE),and the plant... Stomata are tiny pores on the plant leaf surface that regulate the exchange of water and gases between the plant and the external environment.They are crucial for photosynthesis,water use efficiency(WUE),and the plant’s ability to adapt to environmental changes.Stomatal movement is vital for understanding how plants adapt to environmental stress and optimize resource utilization.Changes in environmental conditions,especially the quality and intensity of light throughout the day,affect stomatal dynamics and diurnal behavior,which in turn impact photosynthetic efficiency and water-use efficiency.In this review,we summarize the biophysical principles and mechanisms of stomatal movement regulated by ion transport at the plasma membrane,vacuolar membrane and metabolic activity through persulfidation or S-nitrosylation modifications.Specifically,we focus on recent progress in the regulation of stomatal movement by different light qualities,and summarize the photochemical and biochemical events underlying photoreceptors as well as the knowledge of novel regulatory functions and signaling in the multilayer control of stomatal movement and environmental adaptation.Furthermore,as rising global temperatures and increased water needs of farming methods are expected to escalate future crop losses,we explore the potential of smart LED lighting and gene editing technology in enhancing photosynthetic efficiency and water-use efficiency,leading to increased crop biomass and higher crop yields. 展开更多
关键词 STOMATA light signaling PHOTORECEPTOR PHOTOSYNTHESIS WUE light quality
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Enhancement of Growth and Quality of Chinese Bayberry Using LED Supplemental Lighting
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作者 Ni Tang Chenchun Hao Rong Qiu 《Phyton-International Journal of Experimental Botany》 2025年第8期2551-2562,共12页
Supplemental lighting has emerged as a widely adopted technique in greenhouse cultivation to enhance product visibility andimprove theflavor characteristics ofChinese bayberry(Myrica rubra)in the internationalmarket.W... Supplemental lighting has emerged as a widely adopted technique in greenhouse cultivation to enhance product visibility andimprove theflavor characteristics ofChinese bayberry(Myrica rubra)in the internationalmarket.While studies on lighting have predominantly focused on colorimetry,limited research has addressed the precise control of chromatic parameters and their effect on fruit quality.This study examined the effects of varying lighting conditions,specifically correlated color temperatures and illuminance,on the growth and quality of Chinese bayberry varieties“Black Charcoal”and“Dongkui”using a precision control system.The bayberry plants were exposed to a constant illuminance of 155μmol·m^(-2)·s^(-1) with chromatic levels ranging from 2250 to 6000 K.Black Charcoal demonstrated substantial improvements under different chromatic parameters,with fruit weight and size increasing by 40%and 14%,respectively.Furthermore,soluble solids content increased by 4% and vitamin C content rose by 142%,while organic acid content decreased by 30%.Dongkui,however,showed more modest responses under identical conditions,with fruit weight increasing by 2% and fruit size decreasing by 1%.Soluble solids and vitamin C contents showed minimal increases of 2% and 2.5%,respectively,while organic acid content decreased by 8%.The findings demonstrate that supplemental LED lighting significantly enhances both yield and quality parameters in Black Charcoal compared with Dongkui.These results provide valuable insights for optimizing Chinese bayberry cultivation,and the precise control methodology developed can be used to improve supplemental lighting strategies in other fruit and plant species. 展开更多
关键词 Chinese bayberry artificial light LED lighting YIELD fruit quality color coding
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Interplay of light and nitrogen for plant growth and development
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作者 Chenlong Guan Dong Zhang Chengcai Chu 《The Crop Journal》 2025年第3期641-655,共15页
Light and nitrogen(N)are two critically environmental factors essential for plant survival,as they constitute the fundamental molecular framework of plant cells and significantly influence patterns of plant growth and... Light and nitrogen(N)are two critically environmental factors essential for plant survival,as they constitute the fundamental molecular framework of plant cells and significantly influence patterns of plant growth and development.Light is the driving force behind photosynthesis,a process that converts light energy into chemical energy stored as sugars.Additionally,light acts as a direct signal that can modulate plant morphogenesis and structural development.Nitrogen,as the most crucial mineral nutrient for plants,is a component of numerous biomolecules.It also functions as a signaling molecule,regulating plant growth and development.Moreover,light and nitrogen directly regulate the balance of carbon(C)and N within plants,affecting numerous biochemical reactions and various physiological processes.This review focuses on the interactions between light and nitrogen in physiological,metabolic,and molecular levels.We will also discuss the regulatory networks and mechanisms through which light and nitrogen influence C and N absorption and metabolism in plants. 展开更多
关键词 light NITROGEN PHOTOSYNTHESIS SIGNALING light and nitrogen interplay
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Characterization and optimization of a cryogenic pure CsI detector with remarkable light yield and unprecedented energy resolution for CLOVERS experiment
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作者 Chen-Guang Su Qian Liu +4 位作者 Ling-Quan Kong Shi Chen Kimiya Moharrami Yang-Heng Zheng Jin Li 《Nuclear Science and Techniques》 2025年第5期79-87,共9页
In this study,we comprehensively characterized and optimized a cryogenic pure CsI(pCsI)detector.We utilized a 2 cm×2 cm×2 cm cube crystal coupled with a HAMAMATSU R11065 photomultiplier tube,achieving a rema... In this study,we comprehensively characterized and optimized a cryogenic pure CsI(pCsI)detector.We utilized a 2 cm×2 cm×2 cm cube crystal coupled with a HAMAMATSU R11065 photomultiplier tube,achieving a remarkable light yield of 35.2 PE/ke V_(ee)and an unprecedented energy resolution of 6.9%at 59.54 ke V.Additionally,we measured the scintillation decay time of pCsI,which was significantly shorter than that of CsI(Na)at room temperature.Furthermore,we investigated the impact of temperature,surface treatment and crystal shape on light yield.Notably,the light yield peaked at approximately 20 K and remained stable within the range of 70–100 K.The light yield of the polished crystals was approximately 1.5 times greater than that of the ground crystals,whereas the crystal shape exhibited minimal influence on the light yield.These results are crucial for the design of the 10 kg pCsI detector for the future CLOVERS(coherent elastic neutrino(V)-nucleus scattering at China Spallation Neutron Source(CSNS))experiment. 展开更多
关键词 Cryogenic CsI detector light yield Energy resolution Scintillation decay time light yield optimization CLOVERS CEνNS
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Stray light analysis for the AIMS Telescope
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作者 Biyuan Gao Dongguang Wang +3 位作者 Yingzi Sun Yuliang Shen Xiao Yang Junfeng Hou 《Astronomical Techniques and Instruments》 2025年第5期319-326,共8页
Stray light has a significant effect on the overall performance of telescopes,particularly for infrared solar telescopes,in which internal thermal radiation causes additional stray light sources.We establish a 3-dimen... Stray light has a significant effect on the overall performance of telescopes,particularly for infrared solar telescopes,in which internal thermal radiation causes additional stray light sources.We establish a 3-dimensional model using stray light theory and the real opto-mechanical structure of the Accurate Infrared Magnetic field measurements of the Sun(AIMS)telescope.We use the stray light ratio(i.e.,the ratio of stray light energy reaching the detector to the light energy used for observations)to evaluate the imaging performance of the telescope.We analyze both thermal and non-thermal sources of stray light to comprehensively study the visible,8-10μm,and Fourier transform infrared systems of the telescope,finding stray light ratios of 9.31×10^(-6)in the visible system,2.83×10^(-4)in the 8-10μm system,and 1.54×10^(-4)in the Fourier transform infrared system.This verifies that the opto-mechanical system design of the telescope can effectively suppress stray light,benefiting both imaging and magnetic field observations. 展开更多
关键词 Stray light analysis Non-thermal radiation Thermal radiation Stray light ratio
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The Calibration Method of Line Structured Light Sensor for Integrated Position and Pose Detection of Highway Guardrail Inspection Robots
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作者 WANG Rui BAI Jiadi +4 位作者 XUE Yingqi PENG Lu FENG Xiaofan DING Ailing WEI Baojiang 《Wuhan University Journal of Natural Sciences》 2025年第4期367-378,共12页
The accuracy of center height detection for corrugated beam guardrails is significantly affected by robot posture in the mobile highway guardrail detection systems based on structured light vision.To address the probl... The accuracy of center height detection for corrugated beam guardrails is significantly affected by robot posture in the mobile highway guardrail detection systems based on structured light vision.To address the problem,this paper proposes an integrated calibration method for structured light vision sensors.In the proposed system,the sensor is mounted on a crawler-type mobile robot,which scans and measures the center height of guardrails while in motion.However,due to external disturbances such as uneven road surfaces and vehicle vibrations,the posture of the robot may deviate,causing displacement of the sensor platform and resulting in spatial 3D measurement errors.To overcome this issue,the system integrates inertial measurement unit(IMU)data into the sensor calibration process,enabling realtime correction of posture deviations through sensor fusion.This approach achieves a unified calibration of the structured light vision system,effectively compensates for posture-induced errors,and enhances detection accuracy.A prototype was developed and tested in both laboratory and real highway environments.Experimental results demonstrate that the proposed method enables accurate center height detection of guardrails under complex road conditions,significantly reduces posture-related measurement errors,and greatly improves the efficiency and reliability of traditional detection methods. 展开更多
关键词 highway corrugated guardrail structured light visual scanning structured light sensor calibration guardrail detection robot robot motion posture parameters
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Low-light image enhancement for UAVs guided by a light weighted map
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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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Self-oxygenated wearable light-emitting bandage for photobiomodulation against diabetic wounds
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作者 Shenyan Zhang Lingbao Kong +1 位作者 Penghao Ji Minfeng Huo 《Advanced Photonics Nexus》 2025年第4期42-53,共12页
Chronic diabetic wounds,a common and severe complication of diabetes,are characterized by their inability to heal due to impaired blood and oxygen supply.In addition to glycemic control,various clinical treatments suc... Chronic diabetic wounds,a common and severe complication of diabetes,are characterized by their inability to heal due to impaired blood and oxygen supply.In addition to glycemic control,various clinical treatments such as wound dressings,hyperbaric oxygen therapy,and phototherapy have been employed to manage these wounds.Low-level light therapy has emerged as an effective,noninvasive,and painless therapeutic approach for wound management.However,the bulkiness of traditional light sources and the need for frequent clinic visits have limited its widespread adoption.We have developed a wearable,flexible light-emitting bandage with cyanobacterial impregnation(LEB@Cyan).The bioactive bandage is designed to provide sustained oxygen generation and robust photobiomodulation,promoting keratinocyte migration,fibroblast proliferation,and angiogenesis.This addresses the hypoxic conditions and enhances bioenergetic supply to accelerate the healing process of diabetic wounds.In detail,the wound area of diabetic rats treated with LEB@Cyan showed significant reductions of 74.76%and 96.32%compared with that of LEB-treated diabetic rats and untreated diabetic rats,respectively.Such self-oxygenated wearable light-emitting fabric holds great promise for future clinical and commercial applications,potentially revolutionizing the management of chronic diabetic wounds. 展开更多
关键词 light-emitting fabric diabetic wounds PHOTOBIOMODULATION cyanobacterial impregnation low-level light therapy
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2025 Beijing International Motorcycle Expo:Where Engine Roars Meet Digital Lightscapes
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作者 Zhang Li Zhang Ximeng 《China's Foreign Trade》 2025年第2期53-54,共2页
On April 10,2025,the China International Exhibition Center(Shunyi Pavi l ion)became a symphony of roaring engines and dazzling digital light scapes as the 2025 Beijing International Motorcycle Expo kicked off.Under th... On April 10,2025,the China International Exhibition Center(Shunyi Pavi l ion)became a symphony of roaring engines and dazzling digital light scapes as the 2025 Beijing International Motorcycle Expo kicked off.Under the theme of“Promot ing Safe and Civilized Riding Awareness,Advancing the Orderly Development of Motorcycle Culture”,the event attracted over 150 global enterprises and nearly 200 brands. 展开更多
关键词 civilized riding digital light scapes digital lightscapes motorcycle expo roaring engines global enterprises safe riding motorcycle culture
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A Workable Solution for Reducing the Large Number of Vehicle and Pedestrian Accidents Occurring on a Yellow Light
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作者 Pranav Gupta Silki Arora 《Journal of Transportation Technologies》 2024年第1期82-87,共6页
Traffic intersections are incredibly dangerous for drivers and pedestrians. Statistics from both Canada and the U.S. show a high number of fatalities and serious injuries related to crashes at intersections. In Canada... Traffic intersections are incredibly dangerous for drivers and pedestrians. Statistics from both Canada and the U.S. show a high number of fatalities and serious injuries related to crashes at intersections. In Canada, during 2019, the National Collision Database shows that 28% of traffic fatalities and 42% of serious injuries occurred at intersections. Likewise, the U.S. National Highway Traffic Administration (NHTSA) found that about 40% of the estimated 5,811,000 accidents in the U.S. during the year studied were intersection-related crashes. In fact, a major survey by the car insurance industry found that nearly 85% of drivers could not identify the correct action to take when approaching a yellow traffic light at an intersection. One major reason for these accidents is the “yellow light dilemma,” the ambiguous situation where a driver should stop or proceed forward when unexpectedly faced with a yellow light. This situation is even further exacerbated by the tendency of aggressive drivers to inappropriately speed up on the yellow just to get through the traffic light. A survey of Canadian drivers conducted by the Traffic Injury Research Foundation found that 9% of drivers admitted to speeding up to get through a traffic light. Another reason for these accidents is the increased danger of making a left-hand turn on yellow. According to the National Highway Traffic Safety Association (NHTSA), left turns occur in approximately 22.2% of collisions—as opposed to just 1.2% for right turns. Moreover, a study by CNN found left turns are three times as likely to kill pedestrians than right turns. The reason left turns are so much more likely to cause an accident is because they take a driver against traffic and in the path of oncoming cars. Additionally, most of these left turns occur at the driver’s discretion—as opposed to the distressingly brief left-hand arrow at busy intersections. Drive Safe Now proposes a workable solution for reducing the number of accidents occurring during a yellow light at intersections. We believe this fairly simple solution will save lives, prevent injuries, reduce damage to public and private property, and decrease insurance costs. 展开更多
关键词 Traffic Accidents Yellow light Traffic light Signals INTERSECTION Crashes Collision Traffic Fatalities Traffic Injuries Vehicles SAFETY Speed Limit Driving Pedestrians Bicyclists MOTORCYCLISTS Caution Line Yellow light Dilemma Left Hand Turn on Yellow Distance Smart Road Technology Signs Signage Autonomous Vehicles AVs Road Safety IoT Internet of Things Infrastructure Accident Reduction Driving Habits Stop Line Red light Jumping Pedestrian Safety Caution light Stopping at Intersection Safety at Intersections
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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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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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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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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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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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