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Correlation analysis between fault frequency and service time of underground fluid instruments

Geodesy and Geodynamics 2023年第4期14卷 411-418页

作者： xiao tian Guoying Su The First Monitoring and Application Center China Earthquake AdministrationTianjin 300180China

In this paper, we make a statistical analysis of the fault information of the underground fluid instruments of 12 models in China from January 2021 to May 2022 based on the Pearson correlation coefficient, and compare the fault statistics of the meteorological three-element instruments of 3 models during the study period. The results show that:(1) The numbers of faults of the underground fluid instruments of 12models with different service times are basically positively correlated with the numbers of the corresponding instruments, with good consistency. Moreover, the automatic observation instruments(8models) with more than 30 units are significantly correlated at a 0.05 significance level(95% confidence level). Even at a 0.01 significance level(99% confidence level), there are 7 models(7/8) with significant correlation.(2) The positive and negative correlations between the monthly average number of faults and the corresponding service times of the underground fluid instruments of 12 models with different service times are random, and there are 9 models(75%) with no significant correlation at a 0.05 significance level(95% confidence level), while 12 models(100%) with no significant correlation at a 0.01significance level(99% confidence level).(3) The monthly average numbers of faults of the underground fluid instruments of 12 models are basically 0.02-0.05 times/(unit·month), and the overall fault frequency is low.(4) The fault statistics results of the meteorological three-element instruments of 3 models are consistent with the characteristics of the underground fluid instruments of 12 models. In general,there is no significant correlation between the fault frequency and the service time of underground fluid instruments.(5) The results of this paper demonstrate that the service time of underground fluid instruments cannot be taken as the main reason for whether to update the instruments. Similarly, the fault frequency of the instruments cannot be taken as the main

关键词： Underground fluid instruments Fault frequency Service time Correlation analysis

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高莴苣化学成分研究

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新乡医学院学报 2016年第2期33卷 91-95页

作者：殷田田白意晓庄方方曹轲闫福林新乡医学院药学院河南新乡453003 阆中市人民医院药械科四川阆中637400

目的研究高莴苣根茎的化学成分。方法用柱色谱等方法对其化学成分进行分离纯化,通过核磁共振等现代波谱方法确定化合物结构。结果从高莴苣中共分离得到8个化合物,分别鉴定为:熊果烷-12-烯-11-羰基-3-醇正二十八酸酯(1),木栓酮(2),豆甾醇... 详细信息

目的研究高莴苣根茎的化学成分。方法用柱色谱等方法对其化学成分进行分离纯化,通过核磁共振等现代波谱方法确定化合物结构。结果从高莴苣中共分离得到8个化合物,分别鉴定为:熊果烷-12-烯-11-羰基-3-醇正二十八酸酯(1),木栓酮(2),豆甾醇(3),β-谷甾醇(4),β-胡萝卜苷(5),(2S,3S,4R,10E)-2-[(2R)-2-hydroxytetracosano-ylamino]-10-octadecene-1,3,4-triol(6),Aralia cerebroside(7),2,6-二氧甲基-1,4-苯醌(8)。结论在分离得到的这8个化合物中,化合物1、2、3、7、8为首次从该植物中分离得到,为进一步研究其生物活性奠定了基础。

关键词：菊科高莴苣化学成分

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锆基金属有机框架捕获黄连中的生物碱类药物活性成分

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分析测试学报 2025年第1期44卷 188-194页

作者：司甜甜赵薇王慧张红玉刘小烨容蓉冯娟娟山东中医药大学药学院山东济南250355 济南大学化学化工学院山东济南250022

采用溶剂热法制备了锆基MOF-808,利用其结构优势实现了中药黄连中生物碱类药物活性成分的富集与捕获,并结合其结构特点探讨了其协同低共熔溶剂捕获生物碱类活性成分过程中的相互作用。通过优化孵育捕获等条件,对黄连粗提液中药根碱的回... 详细信息

采用溶剂热法制备了锆基MOF-808,利用其结构优势实现了中药黄连中生物碱类药物活性成分的富集与捕获,并结合其结构特点探讨了其协同低共熔溶剂捕获生物碱类活性成分过程中的相互作用。通过优化孵育捕获等条件,对黄连粗提液中药根碱的回收率达到85.78%,结合高效液相色谱技术建立了检测黄连粗提液中5种生物碱类活性成分的方法。方法的线性范围为0.1~300μg·L^(-1),检出限为0.02~0.05μg·L^(-1),相对标准偏差为0.40%~4.7%,加标回收率达到69.7%~128%。该研究实现了中药黄连中生物碱类活性成分的高效、快速富集与捕获,为MOFs材料在选择性捕获与富集中药有效成分等领域的研究提供了新思路。

关键词：金属有机框架选择性富集色谱分离生物碱活性成分黄连

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Two 3-D multi-cascade co-design inverse methods based on streamline curvature approach and Clebsch formulation for single-stage centrifugal compressors

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航空动力学报 2013年第7期28卷 1526-1538页

作者： tian xiao-pei SHAN Peng School of Energy and Power Engineering Beijing University of Aeronautics and Astronautics

Two strategies extended the single-cascade methods from a compressible three-dimensional inverse method for radial and mixed flow turbomachines to two three-dimensional multi-cascade co-design methods for single-stage centrifugal *** two three-dimensional methods and a typical quasi-threedimensional streamline curvature through-flow inverse method were employed to design the same subsonic high-speed single-stage centrifugal *** compressor performances were simulated by a commercial Reynolds averaged Navier-Stokes(RANS) equations *** studies show that two three-dimensional codesign methods are reasonable and *** was found that : firstly the blade camber angle designed by the three-dimensional methods was larger than that designed by the quasi-three-dimensional method;and secondly with regard to two three-dimensional methods with different boundary conditions,the co-design result differences between the diffusers were small,but those between the deswirlers were relatively large.

关键词： centrifugal compressor through-flow inverse method three-dimensional inverse problem streamline curvature approach Clebsch formulation multi-cascade co-design

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Optimality Conditions for Generalized Convex Nonsmooth Uncertain Multi-objective Fractional Programming

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Journal of the Operations Research Society of China 2023年第4期11卷 809-826页

作者： xiao Pan Guo-Lin Yu tian-tian Gong School of Mathematics and Information Science North Minzu UniversityYinchuan750021NingxiaChina

This paper aims at studying optimality conditions of robust weak efficient solutions for a nonsmooth uncertain multi-objective fractional programming problem(NUMFP).The concepts of two types of generalized convex function pairs,called type-I functions and pseudo-quasi-type-I functions,are introduced in this paper for(NUMFP).Under the assumption that(NUMFP)satisfies the robust constraint qualification with respect to Clarke subdifferential,necessary optimality conditions of the robust weak efficient solution are *** optimality conditions are obtained under pseudo-quasi-type-I generalized convexity ***,we introduce the concept of robust weak saddle points to(NUMFP),and prove two theorems about robust weak saddle *** main results in the present paper are verified by concrete examples.

关键词： Multi-objective fractional programming Robust weak efficient solution Generalized convex function Optimality condition Saddle point

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流式细胞术测定淋巴细胞的分裂

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上海免疫学杂志 2003年第2期23卷 120-122页

作者：李红梅田甜钱晓萍孔宪涛陈慰峰北京医科大学免疫学系北京100083 第二军医大学附属长征医院临床实验科上海200003

为确立流式细胞仪检测淋巴细胞的分裂的新方法 ,利用CFSE标记新鲜分离外周及胸腺淋巴细胞后 ,加入PMA、ConA、抗TCR抗体等培养 3d ,染色进行FACS分析。结果 ,诱导T细胞活化分裂的 3种刺激剂 ,以PMA刺激作用最强 ,ConA次之 ,抗TCR抗体最... 详细信息

为确立流式细胞仪检测淋巴细胞的分裂的新方法 ,利用CFSE标记新鲜分离外周及胸腺淋巴细胞后 ,加入PMA、ConA、抗TCR抗体等培养 3d ,染色进行FACS分析。结果 ,诱导T细胞活化分裂的 3种刺激剂 ,以PMA刺激作用最强 ,ConA次之 ,抗TCR抗体最弱。表明CFSE标记细胞 ,流式细胞仪分析法不仅可以检测单细胞水平上细胞的分裂 ,还可根据荧光强度判断细胞的分裂次数。

关键词：淋巴细胞分裂 CFSE 流式细胞仪

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Investigation of the shortest period Am type eclipsing binary TYC 6408–989–1

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Research in Astronomy and Astrophysics 2021年第3期21卷 107-116页

作者： xiao-Man tian School of Aeronautics Shandong Jiaotong University Jinan 250000China Center for Astronomical Mega-Science Chinese Academy of Sciences Beijing 100101China

The first BV bands photometric observations and the low-resolution spectrum of the shortest period Am type eclipsing binary TYC 6408-989-1 have been *** stellar atmospheric parameters of the primary star were obtained through the spectral fitting as follows:Teff=6990±117 K,log g=4.25±0.26 cm s^(-2),[Fe/H]=-0.45±0.03 *** original spectra obtained by European Southern Observatory(ESO)were processed with an IRAF package by *** on the ESO blue-violet spectra,TYC 6408-989-1 was concluded as a marginal Am(Am:)star with a spectral type of kA3 hF1 mA5Ⅳ-Ⅴidentified through the MKCLASS *** observed light curves were analyzed through the WilsonDevinney *** final photometric solutions show that TYC 6408-989-1 is a marginal contact binary with a low mass ratio(q=0.27).The temperature of the secondary component derived through the light curve analysis is significantly higher than main sequence *** addition,TYC 6408-989-1 is a poor thermal contact *** temperature differences between the two components is about 1800 ***6408-989-1 should be located in the oscillation stage predicted by the thermal relaxation oscillations theory(TRO)and will evolve into the shallow contact stage *** very short period(less than one day),marginal Am peculiarity and quite large rotational velocity(v sin i■160 km s^(-1))make TYC 6408-989-1 become a challenge to the cut-off of rotation velocities and periods of Am *** have collected the well known eclipsing Am binaries with absolute parameters from the literature.

关键词： stars:chemically peculiar stars:binaries:eclipsing stars:binaries:general(TYC 64089891) stars:evolution

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Stability Analysis of Sampled-data Control System and Its Application to Electric Power Market

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Chinese Journal of Electrical Engineering 2020年第1期6卷 61-70页

作者： tian Zhang Shenping xiao School of Electrical and Information Engineering Hunan University of TechnologyZhuzhou 412007China Key Laboratory for Electric Drive Control and Intelligent Equipment of Hunan Province Zhuzhou 412007China

The stability of sampled-data systems is investigated using a new type of Lyapunov *** interval from the sampling point t_(k) to t_(k+1) is assumed to be a sampling *** fully utilizing the characteristic information on the whole sampling interval,a new two-sided closed-loop Lyapunov functional is proposed,which utilizes the information on both the intervals from the sampling point t to k_(t) and from t to t_(k+1).Based on the two-sided closed-loop Lyapunov functional and modified free-matrix-based inequality,a less conservative stability criterion is derived for a sampled-data control system,and three numerical examples are provided to verify the effectiveness and reduced conservativeness of the proposed ***,the proposed method is applied to solve the stability problem of electric power markets,and the practical significance of reducing the conservativeness is discussed.

关键词： Stability sampled-data control system two-sided closed-loop Lyapunov functional electric power market

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LEARNING CAUSAL GRAPHS OF NONLINEAR STRUCTURAL VECTOR AUTOREGRESSIVE MODEL USING INFORMATION THEORY CRITERIA

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Journal of Systems Science & Complexity 2014年第6期27卷 1213-1226页

作者： WEI Yuesong tian Zheng xiao Yanting School of Mathematical Science Huaibei Normal University Department of Applied Mathematics Northwest Polytechnical University

Detection and clarification of cause-effect relationships among variables is an important problem in time series analysis. Traditional causality inference methods have a salient limitation that the model must be linear and with Gaussian noise. Although additive model regression can effectively infer the nonlinear causal relationships of additive nonlinear time series, it suffers from the limitation that contemporaneous causal relationships of variables must be linear and not always valid to test conditional independence relations. This paper provides a nonparametric method that employs both mutual information and conditional mutual information to identify causal structure of a class of nonlinear time series models, which extends the additive nonlinear times series to nonlinear structural vector autoregressive models. An algorithm is developed to learn the contemporaneous and the lagged causal relationships of variables. Simulations demonstrate the effectiveness of the nroosed method.

关键词： Causal graphs conditional independence conditional mutual information nonlinear struc-tural vector autoregressive model.

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Reductions in non-point source pollution through different management practices for an agricultural watershed in the Three Gorges Reservoir Area

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Journal of Environmental Sciences 2010年第2期22卷 184-191页

作者： Yaowu tian Zhilin Huang Wenfa xiao School of Life Science Sun Yat-sen University Guangzhou 510275 China. Key Laboratory of Forest Ecology and Environment State Forest-ry Administration China Research Institute of Forest Ecology Environment and Protection Chinese Academy of Forestry Beijing 10091 China

Non-point source water pollution generated by agricultural production is considered a major environmental issue in the Three Gorges Reservoir Area （TGRA） of China. The Annualised Agricultural Non-Point Source Pollution （AnnAGNPS） model was selected to assess the impact of the application of various management treats, including seven crops, five fertilizer levels and three-group management practice scenarios, on water quality from Heigou River Watershed in TGRA. The scenario subsets include conservation tillage practice （CTP）, conservation reserve program （CRP） and conversion of cropland into forestland program （CCFP）. Results indicated that tea can not be replaced by other crops because comparatively tea resulted in a higher sediment yield. CTP with no-tillage was more effective to reduce sediment yield, but could increased nutrient loss. CRP reduced sediment yield significantly, but slightly benefited on nutrient loss. CCFP reduced not only sediment yield but also the nutrient loss significantly. The conversion of cropland with a slope greater than 10° into forestland was found to be the best scenario as the sediment yield export is less than 5 tons/ha and nutrient loss is within the permissible limit.

关键词： non-point pollution management practice reduction the Three Gorges Reservoir Area

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