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Estimating purple-soil moisture content using Vis-NIR spectroscopy

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Journal of Mountain Science 2020年第9期17卷 2214-2223页

作者： gou yu WEI Jie LI Jin-lin HAN Chen TU Qing-yan LIU Chun-hong School of Geography and Tourism Science Chongqing Normal UniversityChongqing 401331China Chongqing Key Laboratory of Surface Process and Environment Remote Sensing in the Three Gorges Reservoir Area Chongqing 401331China

Soil moisture is essential for plant growth in terrestrial *** study investigated the visible-near infrared(Vis-NIR)spectra of three subgroups of purple soils(calcareous,neutral,and acidic)from western Chongqing,China,containing different water *** relationship between soil moisture and spectral reflectivity(R)was analyzed using four spectral transformations,and estimation models were established for estimating the soil moisture content(SMC)of purple soil based on stepwise multiple linear regression(SMLR)and partial least squares regression(PLSR).We found that soil spectra were similar for different moisture contents,with reflectivity decreasing with increasing moisture content and following the order neutral>calcareous>acidic purple soil(at constant moisture content).Three of the four spectral transformations can highlight spectral sensitivity to SMC and significantly improve the correlation between the reflectance spectra and *** and PLSRmethods provide similar prediction *** PLSR-based model using a first-order reflectivity differential(R?)is more effective for estimating the SMC,and gave coefficient of determination(v2),root mean square errors of validation(RMSEV),and ratio of performance to inter-quartile distance(RPIQ)values of 0.946,1.347,and 6.328,respectively,for the calcareous purple soil,and 0.944,1.818,and 6.569,respectively,for the acidic purple *** neutral purple soil,the best prediction was obtained using the SMLR method with R?transformation,yieldingv2,RMSEV and RPIQ values of 0.973,0.888 and 8.791,*** general,PLSR is more suitable than SMLR for estimating the SMC of purple soil.

关键词： Purple soil Soil moisture Vis-NIR spectroscopy Stepwise multiple linear regression Partial least squares regression

Nocardia cyriacigeorgica infection in a patient with repeated fever and CD4+T cell deficiency:A case report

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World Journal of Clinical Cases 2023年第5期11卷 1175-1181页

作者： Xin Hong You-Qi Ji Meng-yuan Chen Xiao-yu gou yu-Mei Ge Department of Green Pharmaceutical Collaborative Innovation Center School of PharmacyZhejiang University of TechnologyHangzhou 310014Zhejiang ProvinceChina School of Medical Technology and Information Engineering Zhejiang Chinese Medical UniversityHangzhou 310053Zhejiang ProvinceChina The Second Clinical Medical College Zhejiang Chinese Medical UniversityHangzhou 310053Zhejiang ProvinceChina Department of Clinical Laboratory Zhejiang Provincial People's Hospital(Affiliated People's HospitalHangzhou Medical College)Hangzhou 310014Zhejiang ProvinceChina

BACKGROUND Nocardia pneumonia shares similar imaging and clinical features with pulmonary tuberculosis and lung neoplasms,but the treatment and anti-infective medication are completely ***,we report a case of pulmonary nocardiosis caused by Nocardia cyriacigeorgica(***),which was misdiagnosed as community-acquired pneumonia(CAP)with repeated *** SUMMARY A 55-year-old female was diagnosed with community-acquired pneumonia in the local hospital because of repeated fever and chest pain for two *** the anti-infection treatment failed in the local hospital,the patient came to our hospital for further *** computed tomography showed multiple patchy,nodular and strip-shaped high-density shadows in both lungs.A routine haematological examination was performed and showed abnormalities in CD19+B cells and CD4+T *** acid-fast bifurcating filaments and branching gram-positive rods were observed in the bronchoalveolar lavage fluid of the patient under an oil microscope,which was identified by matrix-assisted laser desorption ionization-time of flight mass spectrometry as *** patient’s condition quickly improved after taking 0.96 g compound sulfamethoxazole tablets three times a *** The antibiotic treatment of Nocardia pneumonia is different from that of common *** should be given to the pathogenic examination results of patients with recurrent *** pneumonia is an opportunistic *** with CD4+T-cell deficiency should be aware of Nocardia infection.

关键词： Nocardia pneumonia Nocardia cyriacigeorgica Matrix-assisted laser desorption ionization-time of flight mass spectrometry Infection Lung CD4+T-cell Case report

Damped large amplitude oscillations in a solar prominence and a bundle of coronal loops

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Research in Astronomy and Astrophysics 2016年第11期16卷 19-28页

作者： Quan-Hao Zhang yu-Ming Wang Rui Liu Cheng-Long Shen Min Zhang Ting-yu gou Jia-Jia Liu Kai Liu Zhen-Jun Zhou Shui Wang CAS Key Laboratory of Geospace Environment Department of Geophysics and Planetary Sciences University of Science and Technology of China Hefei 230026 China Synergetic Innovation Center of Quantum Information & Quantum Physics University of Science and Technology of China Hefei 230026 China Collaborative Innovation Center of Astronautical Science and Technology Hefei 230026 China Mengcheng National Geophysical Observatory School of Earth and Space Sciences University of Science and Technology of China Hefei 230026 China Department of Mathematics and Physics Anhui Jianzhu University Hefei 230601 China

We investigate the evolutions of two prominences （P1, P2） and two bundles of coronal loops （L1, L2）, observed with SDO/AIA near the east solar limb on 2012 September 22. It is found that there were large-amplitude oscillations in P1 and L1 but no detectable motions in P2 and L2. These transverse oscillations were triggered by a large-scale coronal wave, originating from a large flare in a remote active region behind the solar limb. By carefully comparing the locations and heights of these oscillating and non-oscillating structures, we conclude that the propagating height of the wave is between 50 Mm and 130 Mm. The wave energy deposited in the oscillating prominence and coronal loops is at least of the order of 10-8 erg. Furthermore, local magnetic field strength and Alfv6n speeds are derived from the oscillating periods and damping time scales, which are extracted from the time series of the oscillations. It is demon- strated that oscillations can be used in not only coronal seismology, but also to reveal the properties of the wave.

关键词： Sun: filaments prominences -- Sun: flares -- Sun: oscillations -- waves

多输入多输出线性定常系统稳定裕度的分析与改进

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控制理论与应用 2014年第1期31卷 105-111页

作者：李信栋苟兴宇北京控制工程研究所北京100190 空间智能控制技术重点实验室北京100190

针对多输入多输出(MIMO)控制系统的稳定裕度求解问题,首先分析了现有的回差阵奇异值法这一计算方法,并得到其解决单输入单输出(SISO)系统的稳定裕度结论,在此基础上,提出两种基于系统回差阵的稳定裕度改进方法;一种是在有限条件下利用... 详细信息

针对多输入多输出(MIMO)控制系统的稳定裕度求解问题,首先分析了现有的回差阵奇异值法这一计算方法,并得到其解决单输入单输出(SISO)系统的稳定裕度结论,在此基础上,提出两种基于系统回差阵的稳定裕度改进方法;一种是在有限条件下利用矩阵的特征值代替奇异值来建立与稳定裕度关系的策略,另一种是利用系统逆回差阵的行列式,通过求其奇异值来计算系统稳定裕度;最后结合工程实例,通过数值仿真验证两种稳定裕度计算方法相比原方法都有不同程度的改进,而且三种方法可以结合起来进行分析,最大化的减小系统稳定裕度结果的保守性.

关键词：回差阵奇异值法特征值逆回差阵稳定裕度

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国外旅游研究知识体系演变与共现

经济管理 2016年第11期42卷 159-173页

作者：余构雄华南理工大学经济与贸易学院广东广州510006

既有文献有少量以关键词为研究对象来探讨国内旅游研究相关信息,然而鲜见对国外旅游研究知识体系的研究。本文以国外旅游学术刊物影响因子及引用率排名最前的《Annals of Tourism Research》和《Tourism Management》1986—2015年载文... 详细信息

既有文献有少量以关键词为研究对象来探讨国内旅游研究相关信息,然而鲜见对国外旅游研究知识体系的研究。本文以国外旅游学术刊物影响因子及引用率排名最前的《Annals of Tourism Research》和《Tourism Management》1986—2015年载文的书写关键词为研究对象,采用文献计量法及内容分析法,历时性与共时性交替贯穿于研究中,通过可视化软件"引文空间分析"进行数据统计分析,籍此演绎国外旅游研究知识体系。研究结果显示:(1)旅游研究知识体系演变呈现宽泛—收缩,其本质是旅游研究知识体系的演变脉络逐渐清晰,其演变呈现"稳中有变""稳优于变"及"热点不再—热点演进—热点连贯"的特点;(2)构建了由旅游研究主要内容、旅游研究地理区域和旅游研究方法组成的国外旅游研究知识体系共现框架。最后,较为细致地探讨国内外旅游业及旅游研究发展历程、旅游研究主要内容、旅游研究地理区域、旅游研究方法的异同,以期为深化国内旅游研究提供借鉴与启示。

关键词：旅游研究知识体系演变共现引文空间

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由回差阵奇异值求稳定裕度的退化算法

控制理论与应用 2016年第4期33卷 460-465页

作者：李信栋苟兴宇北京控制工程研究所北京100190 空间智能控制技术重点实验室北京100190

本文研宄使用回差阵奇异值求多输入多输出(MIMO)线性定常系统稳定裕度的方法.首先对此方法进行退化分析,得到求解单输入单输出(SISO)线性定常系统稳定裕度的算法步骤.在此基础上,讨论退化所得算法与传统稳定裕度的关系;进一步地,详细分... 详细信息

本文研宄使用回差阵奇异值求多输入多输出(MIMO)线性定常系统稳定裕度的方法.首先对此方法进行退化分析,得到求解单输入单输出(SISO)线性定常系统稳定裕度的算法步骤.在此基础上,讨论退化所得算法与传统稳定裕度的关系;进一步地,详细分析此退化算法相比传统稳定裕度的优势,进而指出当系统的增益和相位同时变化时,系统Nyquist曲线g(jω)到临界点(-1,j0)的最短距离min|1+g(jω)|可作为一种更加合理的稳定裕度指标.最后,通过对实例进行数值仿真,说明本文所提退化算法可以克服传统稳定裕度局限性,同时与传统稳定裕度结合得到比较完整的SISO线性系统稳定裕度衡量体系.

关键词：回差阵奇异值法稳定裕度奈奎斯特曲线鲁棒性

含多正弦扰动的航天器无拖曳控制系统性能极限研究

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控制理论与应用 2017年第4期34卷 449-456页

作者：邹奎苟兴宇范达北京控制工程研究所北京100190 空间智能控制技术重点实验室北京100190 钱学森空间技术实验室北京100094

本文研究了航天器无拖曳控制系统的性能极限问题.将空间环境扰动描述为一个阶跃分量、一个平稳随机分量和多个正弦分量的线性组合,利用残余非保守力的稳态方差度量扰动抑制性能,并运用Wiener-Hopf设计方法求解最小灵敏度函数.为确保残... 详细信息

本文研究了航天器无拖曳控制系统的性能极限问题.将空间环境扰动描述为一个阶跃分量、一个平稳随机分量和多个正弦分量的线性组合,利用残余非保守力的稳态方差度量扰动抑制性能,并运用Wiener-Hopf设计方法求解最小灵敏度函数.为确保残余非保守力的渐近平稳性,将最小灵敏度函数表示为反馈系统的频域拓扑结构,并推导了闭环系统的极限指标.结合无拖曳控制指标,讨论了加速度计模式下的传感器、执行器的指标分解问题.

关键词：无拖曳控制谱分解 Wiener-Hopf 指标分解

Correlation between Combined Urinary Metal Exposure and Grip Strength under Three Statistical Models:A Cross-sectional Study in Rural Guangxi

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Biomedical and Environmental Sciences 2024年第1期37卷 3-18页

作者： LIANG yu Jian RONG Jia Hui WANG Xue Xiu CAI Jian Sheng QIN Li Dong LIU Qiu Mei TANG Xu MO Xiao Ting WEI Yan Fei LIN Yin Xia HUANG Shen Xiang LUO Ting yu gou Ruo yu CAO Jie Jing HUANG Chu Wu LU yu Fu QIN Jian ZHANG Zhi Yong Department of Environmental and Occupational Health School of Public HealthGuangxi Medical UniversityNanning 530021GuangxiChina Key Laboratory of Tumor Immunology and Microenvironmental Regulation Guilin Medical UniversityGuilin 541199GuangxiChina Department of Environmental Health and Occupational Medicine School of Public HealthGuilin Medical UniversityGuilin 541199GuangxiChina Guangxi Colleges and Universities Key Laboratory of Prevention and Control of Highly Prevalent Diseases Guangxi Medical UniversityNanning 530021GuangxiChina Guangxi Key Laboratory of Environment and Health Research Guangxi Medical UniversityNanning 530021GuangxiChina Key Laboratory of Longevity and Aging-related Diseases of Chinese Ministry of Education Guangxi Medical UniversityNanning 530021GuangxiChina Guangxi Health Commission Key Laboratory of Entire Lifecycle Health and Care Guilin Medical UniversityGuilin 541199GuangxiChina

Objective This study aimed to investigate the potential relationship between urinary metals copper(Cu),arsenic(As),strontium(Sr),barium(Ba),iron(Fe),lead(Pb)and manganese(Mn)and grip *** We used linear regression models,quantile g-computation and Bayesian kernel machine regression(BKMR)to assess the relationship between metals and grip *** In the multimetal linear regression,Cu(β=−2.119),As(β=−1.318),Sr(β=−2.480),Ba(β=0.781),Fe(β=1.130)and Mn(β=−0.404)were significantly correlated with grip strength(P<0.05).The results of the quantile g-computation showed that the risk of occurrence of grip strength reduction was−1.007(95%confidence interval:−1.362,−0.652;P<0.001)when each quartile of the mixture of the seven metals was *** kernel function regression model analysis showed that mixtures of the seven metals had a negative overall effect on grip strength,with Cu,As and Sr being negatively associated with grip strength *** the total population,potential interactions were observed between As and Mn and between Cu and Mn(P_(interactions) of 0.003 and 0.018,respectively).Conclusion In summary,this study suggests that combined exposure to metal mixtures is negatively associated with grip ***,Sr and As were negatively correlated with grip strength levels,and there were potential interactions between As and Mn and between Cu and Mn.

关键词： Urinary metals Handgrip strength Quantile g-computation Bayesian kernel machine regression

Estimating the Texture of Purple Soils Using Vis-NIR Spectroscopy and Optimized Conversion Models

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Agricultural Sciences 2023年第2期14卷 202-218页

作者： Baina Chen Jie Wei Qiang Tang yu gou Chunhong Liu Chongqing Key Laboratory of Surface Process and Environment Remote Sensing in the Three Gorges Reservoir Area School of Geography and Tourism Chongqing Normal University Chongqing China Chongqing Field Observation and Research Station of Surface Ecological Process in the Three Gorges Reservoir Area School of Geography and Tourism Chongqing Normal University Chongqing China Chongqing Jinfo Mountain Karst Ecosystem National Observation and Research Station School of Geographical Sciences Southwest University Chongqing China

Soil texture is an indicator of soil physical structure which delivers many ecological functions of soils such as thermal regime, plant growth, and soil quality. However, traditional methods for soil texture measurement are time-consuming and labor-intensive. This study attempts to explore an indirect method for rapid estimating the texture of three subgroups of purple soils (i.e. calcareous, neutral, and acidic). 190 topsoil (0 - 10 cm) samples were collected from sloping croplands in Tongnan and Beibei Districts of Chongqing Municipality in China. Vis-NIR spectrum was measured and processed, and stepwise multiple linear regression (SMLR), partial least squares regression (PLSR), and back propagation neural network (BPNN) models were constructed to inform the soil texture. The clay fractions ranged from 4.40% to 27.12% while sand fractions ranged from 0.34% to 36.57%, hereby soil samples encompass three textural classes (i.e. silt, silt loam, and silty clay loam). For the original spectrum, the texture of calcareous and neutral purple soils was not significantly correlated with spectral reflectance and linear models (SMLR and PLSR) exhibited low prediction accuracy. The correlation coefficients and the goodness-of-fits between soil texture and the transformed spectra of all soil groups increased by continuum-removal (CR), first-order differential (R'), and second-order differential (R") transformations. Among them, the R" had the best performance in terms of improving the correlation coefficients and the goodness-of-fits. For the calcareous purple soil, the SMLR exceeds PLSR and BPNN with a higher coefficient of determination (R2) and the ratio of performance to inter-quartile distance (RPIQ) values and lower root mean square error of validation (RMSEV), but for the neutral and acidic purple soils, the PLSR model has a better prediction accuracy. In summary, the linear methods (SMLR and PLSR) are more reliable in estimating the texture of the three purpl

关键词： Soil Texture Vis-NIR Spectra Stepwise Multiple Linear Regression Partial Least Squares Regression Backpropagation Neural Network