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Far-red light: A regulator of plant morphology and photosynthetic capacity 被引量:9
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作者 Tingting Tan Shenglan Li +10 位作者 Yuanfang Fan Zhonglin Wang Muhammad Ali Raza Iram Shafiq Beibei Wang Xiaoling Wu Taiwen Yong Xiaochun Wang Yushan Wu Feng Yang Wenyu Yang 《The Crop Journal》 SCIE CSCD 2022年第2期300-309,共10页
Plant photosynthetic capacity directly determines crop yield. Light quality regulates photosynthetic capacity. This review discusses plant responses to far-red light from the phenotypic to the molecular level, focusin... Plant photosynthetic capacity directly determines crop yield. Light quality regulates photosynthetic capacity. This review discusses plant responses to far-red light from the phenotypic to the molecular level, focusing specifically on the improvement of photosynthetic capacity by adjustment of photosynthetic electron transport and the path of light energy. Far-red light can also regulate leaf angle and increase plant height and leaf area, via expression of associated genes, to capture more light energy.Thus, far-red light regulates plant morphology and photosynthetic capacity. Identifying the mechanism of this regulation may lead to increased crop yields. 展开更多
关键词 far-red light Photosynthetic capacity PHOTOSYSTEM Photosynthetic electron transport
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Overhead supplemental far-red light stimulates tomato growth under intra-canopy lighting with LEDs 被引量:18
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作者 ZHANG Ya-ting ZHANG Yu-qi +1 位作者 YANG Qi-chang LI Tao 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2019年第1期62-69,共8页
Far-red(FR) light regulates phytochrome-mediated morphological and physiological plant responses.This study aims to investigate how greenhouse tomato morphology and production response to different durations of FR lig... Far-red(FR) light regulates phytochrome-mediated morphological and physiological plant responses.This study aims to investigate how greenhouse tomato morphology and production response to different durations of FR light during daytime and at the end of day(EOD).High-wire tomato plants were grown under intra-canopy lighting consisting of red(peak wavelength at 640 nm) and blue(peak wavelength at 450 nm) light-emitting diodes(LEDs) with photosynthetic photon flux density(PPFD) of 144 μmol m–2 s–1 at 10 cm away from the lamps,and combined with overhead supplemental FR light(peak wavelength at 735 nm) with PPFD of 43 μmol m–2 s–1 at 20 cm below the lamps.Plants were exposed to three durations of FR supplemental lighting including: 06:00–18:00(FR12),18:00–19:30(EOD-FR1.5),18:00–18:30(EOD-FR0.5),and control that without supplemental FR light.The results showed that supplemental FR light significantly stimulated stem elongation thereby resulting in longer plants compared with the control.Moreover,FR light altered leaf morphology toward higher leaf length/width ratio and larger leaf area.The altered plant architecture in FR supplemented plants led to a more homogeneous light distribution inside the canopy.Total plant biomass was increased by 9–16% under supplemental FR light in comparison with control,which led to 7–12% increase in ripe fruit yield.Soluble sugar content of the ripe tomato fruit was slightly decreased by longer exposure of the plants to FR light.Dry matter partitioning to different plant organs were not substantially affected by the FR light treatments.No significant differences were observed among the three FR light treatments in plant morphology as well as yield and biomass production.We conclude that under intra-canopy lighting,overhead supplemental FR light stimulates tomato growth and production.And supplementary of EOD-FR0.5 is more favorable,as it consumes less electricity but induces similar effects on plant morphology and yield. 展开更多
关键词 SOLANUM lycopersicum far-red light LEDS intro-canopy lightING morphology yield
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<i>Pinus taeda</i>cDNA Microarray as a Tool for Candidate Gene Identification for Local Red/Far-Red Light Adaptive Response in <i>Pinus sylvestris</i>
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作者 Sonali S. Ranade Sara Abrahamsson +1 位作者 Juha Niemi María Rosario García-Gil 《American Journal of Plant Sciences》 2013年第3期479-493,共15页
Light quality response is a vital environmental cue regulating plant development. Conifers, like angiosperms, respond to the changes in light quality including the level of red (R) and far-red (FR) light, which follow... Light quality response is a vital environmental cue regulating plant development. Conifers, like angiosperms, respond to the changes in light quality including the level of red (R) and far-red (FR) light, which follows a latitudinal cline. R and FR wavelengths form a significant component of the entire plant life cycle, including the initial developmental stages such as seed germination, cotyledon expansion and hypocotyl elongation. With an aim to identify differentially expressed candidate genes, which would provide a clue regarding genes involved in the local adaptive response in Scots pine (Pinus sylvestris) with reference to red/far-red light;we performed a global expression analysis of Scots pine hypocotyls grown under two light treatments, continuous R (cR) and continuous FR (cFR) light;using Pinus taeda cDNA microarrays on bulked hypocotyl tissues from different individuals, which represented different genotypes. This experiment was performed with the seeds collected from northern part of Sweden (Ylinen, 68?N). Interestingly, gene expression pattern with reference to cryptochrome1, a blue light photoreceptor, was relatively high under cFR as compared to cR light treatment. Additionally, the microarray data analysis also revealed expression of 405 genes which was enhanced under cR light treatment;while the expression of 239 genes was enhanced under the cFR light treatment. Differentially expressed genes were re-annotated using Blast2GO tool. These results indicated that cR light acts as promoting factor whereas cFR antagonises the effect in most of the processes like C/N metabolism, photosynthesis and cell wall metabolism which is in accordance with former findings in Arabidopsis. We propose cryptochrome1 as a strong candidate gene to study the adaptive cline response under R and FR light in Scots pine as it shows a differential expression under the two light conditions. 展开更多
关键词 Conifer Cryptochrome1 far-red light Microarray RED light SCOTS Pine
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The red/far-red light photoreceptor FvePhyB regulates tissue elongation and anthocyanin accumulation in woodland strawberry
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作者 Qi Gao Shaoqiang Hu +4 位作者 Xiaoli Wang Fu Han Huifeng Luo Zhongchi Liu Chunying Kang 《Horticulture Research》 SCIE CSCD 2023年第12期204-216,共13页
Light is an important environmental signal that influences plant growth and development.Among the photoreceptors,phytochromes can sense red/far-red light to coordinate various biological processes.However,their functi... Light is an important environmental signal that influences plant growth and development.Among the photoreceptors,phytochromes can sense red/far-red light to coordinate various biological processes.However,their functions in strawberry are not yet known.In this study,we identified an EMS mutant,named P8,in woodland strawberry(Fragaria vesca)that showed greatly increased plant height and reduced anthocyanin content.Mapping-by-sequencing revealed that the causal mutation in FvePhyB leads to premature termination of translation.The light treatment assay revealed that FvePhyB is a bona fide red/far-red light photoreceptor,as it specifically inhibits hypocotyl length under red light.Transcriptome analysis showed that the FvePhyB mutation affects the expression levels of genes involved in hormone synthesis and signaling and anthocyanin biosynthesis in petioles and fruits.The srl mutant with a longer internode is caused by a mutation in the DELLA gene FveRGA1(Repressor of GA1)in the gibberellin pathway.We found that the P8 srl double mutant has much longer internodes than srl,suggesting a synergistic role of FvePhyB and FveRGA1 in this process.Taken together,these results demonstrate the important role of FvePhyB in regulating plant architecture and anthocyanin content in woodland strawberry. 展开更多
关键词 STRAW PHYB light
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Low temperature-mediated repression and far-red light-mediated induction determine morning FLOWERING LOCUS T expression levels 被引量:1
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作者 Hayeon Kim Hye Won Kang +4 位作者 Dae Yeon Hwang Nayoung Lee Akane Kubota Takato Imaizumi Young Hun Song 《Journal of Integrative Plant Biology》 SCIE CAS CSCD 2024年第1期103-120,共18页
In order to flower in the appropriate season,plants monitor light and temperature changes and alter downstream pathways that regulate florigen genes such as Arabidopsis(Arabidopsis thaliana)FLOWERING LOCUS T(FT).In Ar... In order to flower in the appropriate season,plants monitor light and temperature changes and alter downstream pathways that regulate florigen genes such as Arabidopsis(Arabidopsis thaliana)FLOWERING LOCUS T(FT).In Arabidopsis,FT messenger RNA levels peak in the morning and evening under natural long-day conditions(LDs).However,the regulatory mechanisms governing morning FT induction remain poorly understood.The morning FT peak is absent in typical laboratory LDs characterized by high red:far-red light(R:FR)ratios and constant temperatures.Here,we demonstrate that ZEITLUPE(ZTL)interacts with the FT repressors TARGET OF EATs(TOEs),thereby repressing morning FT expression in natural environments.Under LDs with simulated sunlight(R:FR=1.0)and daily temperature cycles,which are natural LD-mimicking environmental conditions,FT transcript levels in the ztl mutant were high specifically in the morning,a pattern that was mirrored in the toe1 toe2 double mutant.Low night-to-morning temperatures increased the inhibitory effect of ZTL on morning FT expression by increasing ZTL protein levels early in the morning.Far-red light counteracted ZTL activity by decreasing its abundance(possibly via phytochrome A(phyA))while increasing GIGANTEA(GI)levels and negatively affecting the formation of the ZTL-GI complex in the morning.Therefore,the phyA-mediated high-irradiance response and GI play pivotal roles in morning FT induction.Our findings suggest that the delicate balance between low temperature-mediated ZTL activity and the far-red light-mediated functions of phyA and GI offers plants flexibility in fine-tuning their flowering time by controlling FT expression in the morning. 展开更多
关键词 far-red light FLOWERING LOCUS T flowering time GIGANTEA low night-to-morning temperature natural long days phytochrome A red to far-red ratio ZEITLUPE
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Effects of far-red light on growth, endogenous hormones, antioxidant capacity and quality of Lettuce
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作者 Lili Meng Jiangfeng Song +1 位作者 Degang Ni Mohamad Anuar Kamaruddin 《Food Production, Processing and Nutrition》 2024年第1期810-822,共13页
This study aimed to explore the effects of various intensities of far-red light on the growth performance,endogenous hormones,antioxidant indices,and overall quality of hydroponically cultivated lettuce.As the control... This study aimed to explore the effects of various intensities of far-red light on the growth performance,endogenous hormones,antioxidant indices,and overall quality of hydroponically cultivated lettuce.As the control treatment,a white LED emitting light at an intensity of 200μmol/(m^(2)·s)was utilized(referred to as CK with an R/FR ratio of 5.5),while two experimental treatments,FT1(R/FR=1.2)and FT2(R/FR=0.8),were established by adding different intensities of far-red light to the CK treatment.The results demonstrated that the application of far-red light,particularly in FT1,led to a significant increase in plant height,leaf area,and lettuce biomass,while simultaneously resulting in a notable reduction in leaf thickness.The content of indole-3-acetic acid(IAA)and abscisic acid(ABA)in response to far-red light treatments exhibited an initial increase followed by a subsequent decrease,with FT2 experiencing a significant decline.The gibberellin(GA_(3))content in FT2 reached its peak on the 35th day,showing a substantial increase of 60.09%compared to CK.Far-red treatments were found to enhance peroxidase(POD)and catalase(CAT)activities,while significantly reducing superoxide dismutase(SOD)activity.In comparison to CK,FT1 exhibited a remarkable 134.33%increase in anthocyanin content.Both FT1 and FT2 significantly boosted vitamin C levels while reducing nitrite content.Additionally,the application of far-red light treatment significantly increased the alcohol and ester content in lettuce leaves.This study establishes a theoretical foundation for enhancing the quality and flavor of lettuce using different far-red light treatments. 展开更多
关键词 LETTUCE far-red light GROWTH Endogenous hormones Antioxidant capacity QUALITY
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Dye-mediated FRET strategy for constructing semi-synthetic large Stokes shift far-red fluorescent protein
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作者 Xuelian Zhou Lu Miao +2 位作者 Wei Zhou Qinglong Qiao Zhaochao Xu 《Chinese Chemical Letters》 2025年第10期287-292,共6页
Red fluorescent proteins with large Stokes shift(LSS-RFPs)are advantageous for multicolor imaging applications that allow simultaneous visualizations of multiple biological events.But it is difficult to develop LSS-RF... Red fluorescent proteins with large Stokes shift(LSS-RFPs)are advantageous for multicolor imaging applications that allow simultaneous visualizations of multiple biological events.But it is difficult to develop LSS-RFPs by extending the emission wavelength of RFPs to far-red region.Here,we employed Forster resonance energy transfer(FRET)strategy to engineer the far-red fluorescent proteins with large Stokes shift.LSS-m Apple and LSS-mCherry were constructed by fusing HaloTag to m Apple and mCherry,allowing the fluorophore TMSi R to be connected to these RFPs.FRET between RFPs and TMSi R enabled them to apply the excitation of donor RFPs to emit far-red fluorescence of acceptor TMSi R.The Stokes shifts of LSS-m Apple and LSS-mCherry were 97 nm and 75 nm,respectively.The high FRET efficiency of LSS-mCherry(E_(FRET)=83.7%)can greatly reduce the fluorescence from the donor channel,which did not affect co-imaging with mCherry.In addition,LSS-mCherry also showed excellent photostability(t_(1/2)=449.3 s),enabling stable confocal fluorescence imaging for 15 min under continuous strong excitation.Furthermore,LSS-mCherry was applied for fluorescence labeling and imaging of the nucleus,mitochondria,lysosomes,and endoplasmic reticulum in living cells.Finally,we applied LSS-mCherry to perform multi-color bioimaging of 2–4 channels,and there was no obvious crosstalk between these channels. 展开更多
关键词 Large Stokes shift far-red fluorescent protein HALOTAG Forster resonance energy transfer(FRET) RHODAMINE
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Obtaining versatile Cr^(3+)-activated phosphors with improved far-red emissions via host composition modulation
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作者 Qiuhong Zhang Rui Sun +4 位作者 Quwei Ni Jianbang Zhou Junhao Li Haiyong Ni Jiansheng Huo 《Journal of Rare Earths》 2025年第5期874-881,共8页
Cr^(3+)-activated spinel-type phosphors have great potential in different application scenes due to their unique sharp and far-red(FR)emission.However,the multi-functionalization of these phosphors is still limited by... Cr^(3+)-activated spinel-type phosphors have great potential in different application scenes due to their unique sharp and far-red(FR)emission.However,the multi-functionalization of these phosphors is still limited by their unsatisfied comprehensive properties.Herein,a simple composition engineering was used to explore versatile phosphors,using Ga^(3+)to substitute Al^(3+)to improve the optical performances of spinel LiAl5-xGa_(x)O_(8):Cr^(3+).The substitution of Ga^(3+)evidently affects the crystal field environment of Cr^(3+)and further accounts for the luminescence optimization.Using the optimized phosphor,two sensitive thermometers based on fluorescence intensity ratio(FIR)technique were explored on account of the different temperature dependencies of^(4)T_(2)→^(4)A_(2)and2E→^(4)A_(2)emission and of R2and R1emission.The maximum relative sensitivity Sr are 1.29%/K at 323 K and 1.94%/K at 298 K,respectively,which are superior to that of the Ga^(3+)-unsubstituted one.Besides,the Ga^(3+)→Al^(3+)substitutions endow the resultant phosphors with larger atomic number(Zeff)and theoretical density,which is more conducive to improving X-ray-stimulated emission for X-ray detection.Finally,the potential applications of the developed phosphor are also reflected in plant growth and night vision surveillance,as it is shown to be capable of matching with the absorption of phytochrome PFRand visualizing objects in the dark.This contribution not only proves that the developed LiAl5-xGa_(x)O_(8):Cr^(3+)FR phosphors are promising versatile platforms,but also provides an essential guidance for designing more novel multi-functional materials. 展开更多
关键词 LiAl_(5-x)Ga_(x)O_8:Cr^(3+) far-red emission Cation substitution Multi-functional phosphors Rare earths
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Low R:FR light ratio enhances calcium nitrate resistance and stomatal movement in tomato seedlings by regulating H_(2)O_(2) accumulation
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作者 Xiaoting Zhou Deyang Ye +7 位作者 Yunxin Tang Yirong Gan Jia Huang Zhonghua Bian Lihong Su Zhongqun He Chaoxing He Shaobo Cheng 《Horticultural Plant Journal》 2025年第2期693-705,共13页
Secondary salinization is a major environmental factor that causes a stress response and growth inhibition in plants in protected agriculture.The positive effect of a low red to far-red light ratio(R:FR)in salt tolera... Secondary salinization is a major environmental factor that causes a stress response and growth inhibition in plants in protected agriculture.The positive effect of a low red to far-red light ratio(R:FR)in salt tolerance through antioxidant defense has been reported,while the underlying model remains obscure.In this study,we used physiological and genetic approaches to investigate the relationship between H_(2)O_(2) signaling and low R:FR-induced salt tolerance and antioxidant capacity in tomato seedlings.This study found that low R:FR treatment with calcium nitrate stress(SL treatment)enhanced the growth of plants and increased the net photosynthetic rate 5 days after stress compared with a higher R:FR ratio and calcium nitrate stress(S treatment).With transcriptomic analysis of tomato leaves at 5 d,compared with CK,most of glutaredoxin genes and antioxidant enzymes were upregulated by S treatment,which were upregulated further by SL treatment.Compared to the S treatment,within 5 days,the H_(2)O_(2) level was increased faster before 24 h and it was slowed down after 24 h by SL treatment,with less H_(2)O_(2) accumulation at 5 d than that of S treatment.The enhancement of gene expression of RBOH genes were also shown at 24 h under SL.It was found that stomatal conductance followed the dynamic change of H_(2)O_(2),with a rapid closure of stomata of a decrease at 3 h and an increase after 9 h in SL treatment compared to S treatment,respectively.There was same trend of stomata opening degrees of tomato leaves observed by optical microscope.However,the inhibitor of H_(2)O_(2) production(DPI pretreatment)weakened the positive effect of low R:FR on the regulation of stomatal movement.In addition,SL treatment increased the antioxidant enzyme activities and proline content and decreased the MDA content as compared to the S treatment,while the enhancement of ROS homeostasis was reduced by the DPI pretreatment.In conclusion,low R:FR improved redox homeostasis and stomatal status under calcium nitrate stress through H_(2)O_(2)signaling,improving the adaptation of tomato seedlings to soil salinization stress. 展开更多
关键词 far-red light Salt stress ROS Stomatal opening RBOHs TOMATO
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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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Stress responsive gene CIPK14 is involved in phytochrome A-mediated far-red light inhibition of greening in Arabidopsis 被引量:5
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作者 QIN YuZhi2,3, GUO Ming1, LI Xu1, XIONG XingYao2,3, HE ChangZheng2,3, NIE XianZhou4 & LIU XuanMing1 1College of Life Science and Biotechnology, Hunan University, Changsha 410082, China 2College of Horticulture and Landscape, Hunan Agricultural University, Changsha 410128, China +1 位作者 3Hunan Provincial Key Laboratory of Crop Germplasm Innovation and Utilization, Hunan Agricultural University, Changsha 410128, China 4Potato Research Centre, Agriculture and Agri-Food Canada, Fredericton, New Brunswick E3B 4Z7, Canada 《Science China(Life Sciences)》 SCIE CAS 2010年第11期1307-1314,共8页
In this study, we show that CIPK14,a stress responsive CBL-interacting protein kinase gene,is involved in phytochrome A-mediated far-red light inhibition of greening in Arabidopsis seedlings. The CIPK14-impairment mut... In this study, we show that CIPK14,a stress responsive CBL-interacting protein kinase gene,is involved in phytochrome A-mediated far-red light inhibition of greening in Arabidopsis seedlings. The CIPK14-impairment mutant cipk14 grown in continuous far-red (FR) light did not show greening when exposed to white light illumination for 15 h. By contrast, the FR-grown phytochrome A null mutant phyA greened within 0.5 h of exposure to white light. Although greening of Col-4 (wild-type) was not completely abolished by FR, it exhibited a significantly decreased greening capacity compared with that of phyA. Further analyses demonstrated that the expression of protochlorophyllide reductase (POR) genes was correlated with the greening ability of the genotypes. In addition, CIPK14 appeared to be regulated by both the circadian clock and PhyA. Taken together, these results suggest that CIPK14 plays a role in PhyA-mediated FR inhibition of seedling greening, and that a Ca-related kinase may be involved in a previously undefined branch point in the phytochrome A signaling pathway. 展开更多
关键词 CHLOROPHYLL CIPK14 far-red light INHIBITION of GREENING POR PHYTOCHROME A
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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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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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