Established in 1984,the Journal of Electronics(China)is the earliest English journal inElectronics in China.Consecutively published since then,the Journal has been vitnessing
Established in 1984,the Journal of Electronics(China)is the earliest English journal inElectronics in China.Consecutively published since then,the Journal has been vitnessing
Established in 1984, the Journal of Electronics (China) is the earliest English journal in Electronics in China. Consecutively published since then, the Journal has been vitnessing and publishing the development of th...Established in 1984, the Journal of Electronics (China) is the earliest English journal in Electronics in China. Consecutively published since then, the Journal has been vitnessing and publishing the development of the Electronics in China and beyond.展开更多
针对SCOPE(soil canopy observation of photosynthesis and energy fluxes)模型模拟冠层净辐射(0.4~2.5μm短波净辐射+2.5~50μm长波净辐射)时假设叶片空间随机分布的问题,开发考虑叶片空间聚集的冠层净辐射模拟新模型。将SCOPE模型的...针对SCOPE(soil canopy observation of photosynthesis and energy fluxes)模型模拟冠层净辐射(0.4~2.5μm短波净辐射+2.5~50μm长波净辐射)时假设叶片空间随机分布的问题,开发考虑叶片空间聚集的冠层净辐射模拟新模型。将SCOPE模型的短波净辐射模块和长波净辐射模块分别用考虑叶片空间聚集的GOST2模型和UFR97模型替换,形成新的冠层净辐射模拟模型NRC(modeling canopy net radiation considering spatial clumping index of leaves);通过浙江省安吉县1个毛竹(Phyllostachys edulis)林样地(1~4年生异龄林,4500株/hm^(2))2023年整年的观测数据验证,对比SCOPE模型和NRC模型对冠层净辐射的模拟结果。SCOPE模型和NRC模型对冠层净辐射的模拟结果都与观测值有强相关性,决定系数(R^(2))分别为0.97和0.99,均方根误差(RMSE)分别为47.24和13.31 W/m^(2)。SCOPE模型模拟得到的短波净辐射(R_(notot))存在低估(R^(2)=0.96,平均偏差MBE=-14.17 W/m^(2)),长波净辐射(R nttot)存在高估(R^(2)=0.46;MBE=50.27 W/m^(2)),而NRC模型分别成功模拟了R_(notot)(R^(2)=0.99,MBE=1.44 W/m^(2))和R nttot(R^(2)=0.71;MBE=1.34 W/m^(2))。NRC模型具备模拟叶片空间聚集条件下冠层净辐射的潜力。展开更多
Objectives This scoping review aimed to identify and summarize the current research on virtual reality(VR)technologies used for health education in cancer patients,as well as to identify key areas of application.Metho...Objectives This scoping review aimed to identify and summarize the current research on virtual reality(VR)technologies used for health education in cancer patients,as well as to identify key areas of application.Methods In accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses Extension for Scoping Reviews guidelines,a comprehensive literature search was performed across 11 electronic databases and gray literature sources from inception to 12 September 2025.Studies employing immersive VR tools to improve health education outcomes in cancer patients were included.Data extraction and thematic synthesis were conducted to map evidence regarding VR modalities,educational applications,and outcome measures.Results Twenty-eight studies met the inclusion criteria.VR was applied across four primary educational scenarios,including radiotherapy,chemotherapy,surgery,and healthy behavior(including rehabilitation,smoking cessation,and self-management).Eight distinct VR modalities were identified,namely VR videos,virtual environments,virtual environment for radiotherapy training(VERT),VR interactions,3D models,VR games,VR non-player characters(VR NPCs),and virtual libraries.Among these,VR videos(50.0%),virtual environments(46.4%),and VR interactions(28.6%)were the most frequently employed.The interventions led to significant improvements in patient knowledge,skills,attitudes,health behaviors,and psychological well-being.A clear evolution in VR educational approaches has been observed,shifting from static environmental familiarization toward interactive,gamified,and intelligence-driven experiences.Nevertheless,notable gaps remain regarding safety protocols and data privacy protections,with only a minority of studies addressing these issues.Conclusions VR technologies demonstrate considerable promise as an innovative educational tool in oncology care,enhancing patient understanding,psychological preparedness,and engagement throughout the cancer journey.Future implementation must address infrastructural,ethical,and user-centered design barriers to facilitate the scalable and sustainable integration of this approach into clinical practice.展开更多
This scoping review aims to synthesize evidence on exercise interventions for adolescents with depression by examining their components and evaluating their effects,thereby informing the development of standardized ex...This scoping review aims to synthesize evidence on exercise interventions for adolescents with depression by examining their components and evaluating their effects,thereby informing the development of standardized exercise programs for this population.Based on the Arksey and O’Malley framework for scoping reviews,the following databases were systematically searched:PubMed,Web of Science,Cochrane Library,Embase,EBSCO,China National Knowledge Infrastructure,Wanfang Database,VIP Database,and China Biomedical Literature Database.Based on the inclusion and exclusion criteria,the original studies applying exercise intervention in adolescents with depression were screened.A total of 9 papers were included,including 7 randomized controlled trials,1 quasi-experimental study,and 1 mixed study.The types of exercise interventions included aerobic exercise,resistance training,anti-gravity exercise,and stretching.The frequency of exercise was 30–60 min,3–5 times per week in most studies,with most intensities being moderate to high.Exercise intervention is feasible and effective in adolescents with depression.Nursing staff play a crucial role in implementing and supervising these interventions,from initial assessment to continuous monitoring of motivation and safety.In future studies,healthcare professionals should focus on assessing the condition and physical functional status of adolescents with depression and improving the specific content of exercise intervention to develop a scientific and standardized exercise training program for adolescents with depression.展开更多
BACKGROUND:To provide a comprehensive analysis of the landscape of artifi cial intelligence(AI)applications in cardiac arrest(CA).METHODS:Comprehensive searches were conducted in PubMed,the Cochrane Library,Webof Scie...BACKGROUND:To provide a comprehensive analysis of the landscape of artifi cial intelligence(AI)applications in cardiac arrest(CA).METHODS:Comprehensive searches were conducted in PubMed,the Cochrane Library,Webof Science,and EMBASE from database inception through 10 June 2025.Studies that applied AI inboth in-hospital cardiac arrest(IHCA)and out-of-hospital cardiac arrest(OHCA)populations acrossthe following domains were included:prediction of cardiac arrest occurrence,prognostication ofCA outcomes,applications of large language models(LLMs),and evaluation of cardiopulmonaryresuscitation(CPR)and other AI-driven interventions related to CA.RESULTS:The scoping review included 114 studies,encompassing data from 9,574,462patients in total.AI was most commonly applied to the prediction of CA(overall,n=40;IHCA,n=30;OHCA,n=4;and both,n=6),CPR-related decision support during CA(n=16),and post-arrestprognosis and rehabilitation outcomes(overall,n=38;OHCA,n=21;IHCA,n=3;and both,n=14).Additional application areas included LLM-based applications(n=8),emergency call handling(n=4),wearable device-based detection(n=3),heart rhythm identification(n=2),education(n=2),and extracorporeal cardiopulmonary resuscitation(ECPR)candidate identifi cation(n=1).Across allapplication scenarios,the highest area under the receiver operating characteristic curve(AUROC)value for pre-arrest CA prediction in IHCA patients was 0.998 using a multilayer perceptron(MLP)model,whereas the optimal AUROC for pre-arrest CA prediction in OHCA patients was 0.950 usingextreme gradient boosting(XGBoost)or random forest(RF)models.For CPR-related decisionsupport during CA,the highest AUROC achieved was 0.990 with a convolutional neural network(CNN)model.In prognostic prediction,the optimal AUROC for IHCA patients was 0.960 usingXGBoost,while for OHCA patients it reached 0.976 using an MLP model.CONCLUSION:This review shows that AI is most commonly used for the prediction of CA andCPR-related support,as well as post-arrest and rehabilitation outcomes.Future research directions includedrug discovery,post-resuscitation management,neurorehabilitation,and clinical trial innovation.Furtherstudies should prioritize multicenter clinical trials to evaluate AI models in real-world settings and validatetheir eff ectiveness across diverse patient populations.Overall,AI has signifi cant potential to improve clinicalpractice,and its role in CA application is increasingly important.展开更多
Previous solar probes have relied on solar energy for power,but in the near-solar environment,traditional solar panels are prone to overheating and radiation damage,increasing system complexity and reducing power reli...Previous solar probes have relied on solar energy for power,but in the near-solar environment,traditional solar panels are prone to overheating and radiation damage,increasing system complexity and reducing power reliability.This study introduces a dual-power system integrating solar-thermal thermoelectric generation with photovoltaic technology.First,suitable thermoelectric materials are screened,the geometric structure of the thermoelectric devices is simulated,and then the fabricated thermoelectric devices are subjected to cyclic heatingcooling power generation tests and long-duration high-temperature power generation tests.The results demonstrate that a single thermoelectric device can stably provide 3.5 W of power with excellent cycling stability.Additionally,this study discusses design concepts for energy storage and intelligent energy management systems required by the dualpower system.Designed for the Solar Close Observations and Proximity Experiments(SCOPE)mission,this dualpower supply system integrates the benefits of both to address demands under varying environmental conditions.展开更多
The Journal of Acupuncture and Tuina Science,a peerreview journal with an international scope(ISSN 1672-3597,CN 31-1908/R,Bimonthly),is indexed in Emerging Sources Citation Index(ESCI),Western Pacific Region Index Med...The Journal of Acupuncture and Tuina Science,a peerreview journal with an international scope(ISSN 1672-3597,CN 31-1908/R,Bimonthly),is indexed in Emerging Sources Citation Index(ESCI),Western Pacific Region Index Medicus(WPRIM),Springer-Verlag GmbH Database,Index of Copernicus(IC),Chemical Abstracts(CA),Chinese Science Citation Database(CSCD),and Chinese Scientific and Technical Papers and Citations Database(CSTPCD).You can search the text on https://link.springer.com/journal/11726.展开更多
Finally,a horoscope that understands your life in Shanghai,Pisces 2.20-3.20 Pisces-you're hankering to play matchmaker,aren't you?Well,set your friends up and you may be rewarded with a romantic surprise of yo...Finally,a horoscope that understands your life in Shanghai,Pisces 2.20-3.20 Pisces-you're hankering to play matchmaker,aren't you?Well,set your friends up and you may be rewarded with a romantic surprise of your own.If your date suggests eating at Highline,they're the One.展开更多
Finally,a horoscope that understands your life in Shanghai.Gemini 5.22-6.21 The stars spell relationship problems for you,Gemini,so get off Tantan and focus on your significant other,damn it.Take him of her on a omant...Finally,a horoscope that understands your life in Shanghai.Gemini 5.22-6.21 The stars spell relationship problems for you,Gemini,so get off Tantan and focus on your significant other,damn it.Take him of her on a omantic walk along the Bund.Bring warm Tsingtaos for good luck.展开更多
Finally,a horoscope that understands your life in China.Leo 7.23~8.23 The Sun in your sign means it's your time to shine.Pay attention to the small things that keep you grounded,like the microorganisms between you...Finally,a horoscope that understands your life in China.Leo 7.23~8.23 The Sun in your sign means it's your time to shine.Pay attention to the small things that keep you grounded,like the microorganisms between your toes.Stay humble while you bask in the spotlight.展开更多
Gemini 5.22-6.21 Romance is in tlie air and after last month’s home renovations,it’s time to invite that guy/gal you’ve been seeing to your place Remember to stash your copies of That’s Shanghai,though,so s/he do...Gemini 5.22-6.21 Romance is in tlie air and after last month’s home renovations,it’s time to invite that guy/gal you’ve been seeing to your place Remember to stash your copies of That’s Shanghai,though,so s/he doesn’t catch you following horoscopes.展开更多
Finally,a horoscope that understands your life in China.Scorpio.10.24~11.22.With the sun and Mars in your sign,Scorpio,you'rea force to bereckoned with.Use your intensity wisely,like a superhero saving the day.
Finally,a horoscope that understands your lite in Guangzhou.Cancer 6.22-7.22 Be careful with your food choices this month;that jianbing you're craving might turn out to be about as trustworthy as that guy yelling&...Finally,a horoscope that understands your lite in Guangzhou.Cancer 6.22-7.22 Be careful with your food choices this month;that jianbing you're craving might turn out to be about as trustworthy as that guy yelling"Taxi?Taxi?"at you as you exit Baiyun Airport Play it safe and avoid street eats until at least August.展开更多
叶绿素作为植物光合作用的主体,在监测植被生长状态,评估固碳能力方面发挥着巨大的作用。遥感技术作为一种高效低成本的对地观测技术,能够通过叶片反射光谱特征实现叶绿素含量(chlorophyll content,Cab,含量为面密度)的估算。然而,叶片...叶绿素作为植物光合作用的主体,在监测植被生长状态,评估固碳能力方面发挥着巨大的作用。遥感技术作为一种高效低成本的对地观测技术,能够通过叶片反射光谱特征实现叶绿素含量(chlorophyll content,Cab,含量为面密度)的估算。然而,叶片光谱会受到叶片含水量、叶细胞结构等影响,从而降低遥感估算Cab的精度。而日光诱导叶绿素荧光(solar-induced chlorophyll fluorescence,SIF)遥感是直接探测叶绿素激发荧光信息,其变化特征与Cab直接相关,在Cab估算中有巨大的潜力。为此,以荧光辐射传输模型(soil canopy observation,photo-chemistry and energy fluxes,SCOPE)为工具,通过敏感性分析确定Cab荧光敏感波段,并建立基于荧光光谱的Cab估算模型,最后利用实测数据验证模型的鲁棒性。研究结果表明,700、730 nm分别为叶绿素高、低敏感波段(SIF_(700)、SIF_(730)),760 nm为叶绿素高相关性波段(SIF_(760)),以此3波段建立基于荧光比值的Cab估算模型,其中,以SIF_(760)与SIF_(700)的荧光比值建模精度最优,决定系数R2为0.9981,均方根误差(root mean square error,RMSE)为0.0435μg/cm^(2)。SIF_(700)与SIF_(730)荧光比值和Cab的建模精度最低,但R2和RMSE也分别达到了0.9048和0.0886μg/cm^(2)。利用实测数据独立样本对上述3种估算方法进行验证,SIF_(760)/SIF_(730)估算结果表现最佳,RMSE为0.2108μg/cm^(2),SIF_(700)/SIF_(730)次之,RMSE为0.3454μg/cm^(2),但呈现出整体高估现象;SIF_(760)/SIF_(700)估算结果与实测数据偏差较大,RMSE为0.7435μg/cm^(2)。综上,SIF_(760)/SIF_(730)构建的比值植被指数在估算Cab过程中不仅能够保证很好的建模精度,同时又表现出极佳的鲁棒性。研究结果为利用叶绿素荧光遥感手段进行叶片生化参数估算提供技术参考。展开更多
文摘Established in 1984,the Journal of Electronics(China)is the earliest English journal inElectronics in China.Consecutively published since then,the Journal has been vitnessing
文摘Established in 1984,the Journal of Electronics(China)is the earliest English journal inElectronics in China.Consecutively published since then,the Journal has been vitnessing
文摘Established in 1984, the Journal of Electronics (China) is the earliest English journal in Electronics in China. Consecutively published since then, the Journal has been vitnessing and publishing the development of the Electronics in China and beyond.
文摘针对SCOPE(soil canopy observation of photosynthesis and energy fluxes)模型模拟冠层净辐射(0.4~2.5μm短波净辐射+2.5~50μm长波净辐射)时假设叶片空间随机分布的问题,开发考虑叶片空间聚集的冠层净辐射模拟新模型。将SCOPE模型的短波净辐射模块和长波净辐射模块分别用考虑叶片空间聚集的GOST2模型和UFR97模型替换,形成新的冠层净辐射模拟模型NRC(modeling canopy net radiation considering spatial clumping index of leaves);通过浙江省安吉县1个毛竹(Phyllostachys edulis)林样地(1~4年生异龄林,4500株/hm^(2))2023年整年的观测数据验证,对比SCOPE模型和NRC模型对冠层净辐射的模拟结果。SCOPE模型和NRC模型对冠层净辐射的模拟结果都与观测值有强相关性,决定系数(R^(2))分别为0.97和0.99,均方根误差(RMSE)分别为47.24和13.31 W/m^(2)。SCOPE模型模拟得到的短波净辐射(R_(notot))存在低估(R^(2)=0.96,平均偏差MBE=-14.17 W/m^(2)),长波净辐射(R nttot)存在高估(R^(2)=0.46;MBE=50.27 W/m^(2)),而NRC模型分别成功模拟了R_(notot)(R^(2)=0.99,MBE=1.44 W/m^(2))和R nttot(R^(2)=0.71;MBE=1.34 W/m^(2))。NRC模型具备模拟叶片空间聚集条件下冠层净辐射的潜力。
基金supported by a project supported by Scientific Research Fund of Zhejiang Provincial Education Department(Grant number Y202457058).
文摘Objectives This scoping review aimed to identify and summarize the current research on virtual reality(VR)technologies used for health education in cancer patients,as well as to identify key areas of application.Methods In accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses Extension for Scoping Reviews guidelines,a comprehensive literature search was performed across 11 electronic databases and gray literature sources from inception to 12 September 2025.Studies employing immersive VR tools to improve health education outcomes in cancer patients were included.Data extraction and thematic synthesis were conducted to map evidence regarding VR modalities,educational applications,and outcome measures.Results Twenty-eight studies met the inclusion criteria.VR was applied across four primary educational scenarios,including radiotherapy,chemotherapy,surgery,and healthy behavior(including rehabilitation,smoking cessation,and self-management).Eight distinct VR modalities were identified,namely VR videos,virtual environments,virtual environment for radiotherapy training(VERT),VR interactions,3D models,VR games,VR non-player characters(VR NPCs),and virtual libraries.Among these,VR videos(50.0%),virtual environments(46.4%),and VR interactions(28.6%)were the most frequently employed.The interventions led to significant improvements in patient knowledge,skills,attitudes,health behaviors,and psychological well-being.A clear evolution in VR educational approaches has been observed,shifting from static environmental familiarization toward interactive,gamified,and intelligence-driven experiences.Nevertheless,notable gaps remain regarding safety protocols and data privacy protections,with only a minority of studies addressing these issues.Conclusions VR technologies demonstrate considerable promise as an innovative educational tool in oncology care,enhancing patient understanding,psychological preparedness,and engagement throughout the cancer journey.Future implementation must address infrastructural,ethical,and user-centered design barriers to facilitate the scalable and sustainable integration of this approach into clinical practice.
文摘This scoping review aims to synthesize evidence on exercise interventions for adolescents with depression by examining their components and evaluating their effects,thereby informing the development of standardized exercise programs for this population.Based on the Arksey and O’Malley framework for scoping reviews,the following databases were systematically searched:PubMed,Web of Science,Cochrane Library,Embase,EBSCO,China National Knowledge Infrastructure,Wanfang Database,VIP Database,and China Biomedical Literature Database.Based on the inclusion and exclusion criteria,the original studies applying exercise intervention in adolescents with depression were screened.A total of 9 papers were included,including 7 randomized controlled trials,1 quasi-experimental study,and 1 mixed study.The types of exercise interventions included aerobic exercise,resistance training,anti-gravity exercise,and stretching.The frequency of exercise was 30–60 min,3–5 times per week in most studies,with most intensities being moderate to high.Exercise intervention is feasible and effective in adolescents with depression.Nursing staff play a crucial role in implementing and supervising these interventions,from initial assessment to continuous monitoring of motivation and safety.In future studies,healthcare professionals should focus on assessing the condition and physical functional status of adolescents with depression and improving the specific content of exercise intervention to develop a scientific and standardized exercise training program for adolescents with depression.
基金supported by grant from the National Natural Science Foundation of China(82372207).
文摘BACKGROUND:To provide a comprehensive analysis of the landscape of artifi cial intelligence(AI)applications in cardiac arrest(CA).METHODS:Comprehensive searches were conducted in PubMed,the Cochrane Library,Webof Science,and EMBASE from database inception through 10 June 2025.Studies that applied AI inboth in-hospital cardiac arrest(IHCA)and out-of-hospital cardiac arrest(OHCA)populations acrossthe following domains were included:prediction of cardiac arrest occurrence,prognostication ofCA outcomes,applications of large language models(LLMs),and evaluation of cardiopulmonaryresuscitation(CPR)and other AI-driven interventions related to CA.RESULTS:The scoping review included 114 studies,encompassing data from 9,574,462patients in total.AI was most commonly applied to the prediction of CA(overall,n=40;IHCA,n=30;OHCA,n=4;and both,n=6),CPR-related decision support during CA(n=16),and post-arrestprognosis and rehabilitation outcomes(overall,n=38;OHCA,n=21;IHCA,n=3;and both,n=14).Additional application areas included LLM-based applications(n=8),emergency call handling(n=4),wearable device-based detection(n=3),heart rhythm identification(n=2),education(n=2),and extracorporeal cardiopulmonary resuscitation(ECPR)candidate identifi cation(n=1).Across allapplication scenarios,the highest area under the receiver operating characteristic curve(AUROC)value for pre-arrest CA prediction in IHCA patients was 0.998 using a multilayer perceptron(MLP)model,whereas the optimal AUROC for pre-arrest CA prediction in OHCA patients was 0.950 usingextreme gradient boosting(XGBoost)or random forest(RF)models.For CPR-related decisionsupport during CA,the highest AUROC achieved was 0.990 with a convolutional neural network(CNN)model.In prognostic prediction,the optimal AUROC for IHCA patients was 0.960 usingXGBoost,while for OHCA patients it reached 0.976 using an MLP model.CONCLUSION:This review shows that AI is most commonly used for the prediction of CA andCPR-related support,as well as post-arrest and rehabilitation outcomes.Future research directions includedrug discovery,post-resuscitation management,neurorehabilitation,and clinical trial innovation.Furtherstudies should prioritize multicenter clinical trials to evaluate AI models in real-world settings and validatetheir eff ectiveness across diverse patient populations.Overall,AI has signifi cant potential to improve clinicalpractice,and its role in CA application is increasingly important.
基金supported by National Key R&D Program of China(2022YFF0503804).
文摘Previous solar probes have relied on solar energy for power,but in the near-solar environment,traditional solar panels are prone to overheating and radiation damage,increasing system complexity and reducing power reliability.This study introduces a dual-power system integrating solar-thermal thermoelectric generation with photovoltaic technology.First,suitable thermoelectric materials are screened,the geometric structure of the thermoelectric devices is simulated,and then the fabricated thermoelectric devices are subjected to cyclic heatingcooling power generation tests and long-duration high-temperature power generation tests.The results demonstrate that a single thermoelectric device can stably provide 3.5 W of power with excellent cycling stability.Additionally,this study discusses design concepts for energy storage and intelligent energy management systems required by the dualpower system.Designed for the Solar Close Observations and Proximity Experiments(SCOPE)mission,this dualpower supply system integrates the benefits of both to address demands under varying environmental conditions.
文摘The Journal of Acupuncture and Tuina Science,a peerreview journal with an international scope(ISSN 1672-3597,CN 31-1908/R,Bimonthly),is indexed in Emerging Sources Citation Index(ESCI),Western Pacific Region Index Medicus(WPRIM),Springer-Verlag GmbH Database,Index of Copernicus(IC),Chemical Abstracts(CA),Chinese Science Citation Database(CSCD),and Chinese Scientific and Technical Papers and Citations Database(CSTPCD).You can search the text on https://link.springer.com/journal/11726.
文摘Finally,a horoscope that understands your life in Shanghai,Pisces 2.20-3.20 Pisces-you're hankering to play matchmaker,aren't you?Well,set your friends up and you may be rewarded with a romantic surprise of your own.If your date suggests eating at Highline,they're the One.
文摘Finally,a horoscope that understands your life in Shanghai.Gemini 5.22-6.21 The stars spell relationship problems for you,Gemini,so get off Tantan and focus on your significant other,damn it.Take him of her on a omantic walk along the Bund.Bring warm Tsingtaos for good luck.
文摘Finally,a horoscope that understands your life in China.Leo 7.23~8.23 The Sun in your sign means it's your time to shine.Pay attention to the small things that keep you grounded,like the microorganisms between your toes.Stay humble while you bask in the spotlight.
文摘Gemini 5.22-6.21 Romance is in tlie air and after last month’s home renovations,it’s time to invite that guy/gal you’ve been seeing to your place Remember to stash your copies of That’s Shanghai,though,so s/he doesn’t catch you following horoscopes.
文摘Finally,a horoscope that understands your life in China.Scorpio.10.24~11.22.With the sun and Mars in your sign,Scorpio,you'rea force to bereckoned with.Use your intensity wisely,like a superhero saving the day.
文摘Finally,a horoscope that understands your lite in Guangzhou.Cancer 6.22-7.22 Be careful with your food choices this month;that jianbing you're craving might turn out to be about as trustworthy as that guy yelling"Taxi?Taxi?"at you as you exit Baiyun Airport Play it safe and avoid street eats until at least August.
文摘叶绿素作为植物光合作用的主体,在监测植被生长状态,评估固碳能力方面发挥着巨大的作用。遥感技术作为一种高效低成本的对地观测技术,能够通过叶片反射光谱特征实现叶绿素含量(chlorophyll content,Cab,含量为面密度)的估算。然而,叶片光谱会受到叶片含水量、叶细胞结构等影响,从而降低遥感估算Cab的精度。而日光诱导叶绿素荧光(solar-induced chlorophyll fluorescence,SIF)遥感是直接探测叶绿素激发荧光信息,其变化特征与Cab直接相关,在Cab估算中有巨大的潜力。为此,以荧光辐射传输模型(soil canopy observation,photo-chemistry and energy fluxes,SCOPE)为工具,通过敏感性分析确定Cab荧光敏感波段,并建立基于荧光光谱的Cab估算模型,最后利用实测数据验证模型的鲁棒性。研究结果表明,700、730 nm分别为叶绿素高、低敏感波段(SIF_(700)、SIF_(730)),760 nm为叶绿素高相关性波段(SIF_(760)),以此3波段建立基于荧光比值的Cab估算模型,其中,以SIF_(760)与SIF_(700)的荧光比值建模精度最优,决定系数R2为0.9981,均方根误差(root mean square error,RMSE)为0.0435μg/cm^(2)。SIF_(700)与SIF_(730)荧光比值和Cab的建模精度最低,但R2和RMSE也分别达到了0.9048和0.0886μg/cm^(2)。利用实测数据独立样本对上述3种估算方法进行验证,SIF_(760)/SIF_(730)估算结果表现最佳,RMSE为0.2108μg/cm^(2),SIF_(700)/SIF_(730)次之,RMSE为0.3454μg/cm^(2),但呈现出整体高估现象;SIF_(760)/SIF_(700)估算结果与实测数据偏差较大,RMSE为0.7435μg/cm^(2)。综上,SIF_(760)/SIF_(730)构建的比值植被指数在估算Cab过程中不仅能够保证很好的建模精度,同时又表现出极佳的鲁棒性。研究结果为利用叶绿素荧光遥感手段进行叶片生化参数估算提供技术参考。
