期刊文献+
共找到1,014篇文章
< 1 2 51 >
每页显示 20 50 100
Drought trend analysis in a semi-arid area of Iraq based on Normalized Difference Vegetation Index, Normalized Difference Water Index and Standardized Precipitation Index 被引量:1
1
作者 Ayad M F AL-QURAISHI Heman A GAZNAYEE Mattia CRESPI 《Journal of Arid Land》 SCIE CSCD 2021年第4期413-430,共18页
Drought was a severe recurring phenomenon in Iraq over the past two decades due to climate change despite the fact that Iraq has been one of the most water-rich countries in the Middle East in the past.The Iraqi Kurdi... Drought was a severe recurring phenomenon in Iraq over the past two decades due to climate change despite the fact that Iraq has been one of the most water-rich countries in the Middle East in the past.The Iraqi Kurdistan Region(IKR)is located in the north of Iraq,which has also suffered from extreme drought.In this study,the drought severity status in Sulaimaniyah Province,one of four provinces of the IKR,was investigated for the years from 1998 to 2017.Thus,Landsat time series dataset,including 40 images,were downloaded and used in this study.The Normalized Difference Vegetation Index(NDVI)and the Normalized Difference Water Index(NDWI)were utilized as spectral-based drought indices and the Standardized Precipitation Index(SPI)was employed as a meteorological-based drought index,to assess the drought severity and analyse the changes of vegetative cover and water bodies.The study area experienced precipitation deficiency and severe drought in 1999,2000,2008,2009,and 2012.Study findings also revealed a drop in the vegetative cover by 33.3%in the year 2000.Furthermore,the most significant shrinkage in water bodies was observed in the Lake Darbandikhan(LDK),which lost 40.5%of its total surface area in 2009.The statistical analyses revealed that precipitation was significantly positively correlated with the SPI and the surface area of the LDK(correlation coefficients of 0.92 and 0.72,respectively).The relationship between SPI and NDVI-based vegetation cover was positive but not significant.Low precipitation did not always correspond to vegetative drought;the delay of the effect of precipitation on NDVI was one year. 展开更多
关键词 climate change DROUGHT normalized Difference Vegetation Index(NDVI) normalized Difference Water Index(NDWI) standardized Precipitation Index(SPI) delay effect
在线阅读 下载PDF
Semi-Simple Algebras and Normality of Closed Subsets in Standard Table Algebras
2
作者 CHEN Sheng'an 《Wuhan University Journal of Natural Sciences》 CAS CSCD 2017年第5期369-372,共4页
By using Artin-Wedderburn Theorem and the decomp- osition of central edepotent, several results about normality on closed subsets in standard table algebras are generalized to complex semi-simple algebras and the proo... By using Artin-Wedderburn Theorem and the decomp- osition of central edepotent, several results about normality on closed subsets in standard table algebras are generalized to complex semi-simple algebras and the proofs are easier than the original ones. 展开更多
关键词 semi-simple algebra standard table algebra normal closed subset central idempotent
原文传递
What is "normal" intraoperative blood pressure and do deviations from it really affect postoperative outcome?
3
作者 David Li Christian Bohringer Hong Liu 《The Journal of Biomedical Research》 CAS CSCD 2017年第2期79-81,共3页
In our clinical practice, we are accustomed to dealing with perioperative hemodynamic and blood pressure changes on a daily basis. Intraoperative blood pressure variations outside of the accepted "normal" physiologi... In our clinical practice, we are accustomed to dealing with perioperative hemodynamic and blood pressure changes on a daily basis. Intraoperative blood pressure variations outside of the accepted "normal" physiologic ranges are in fact very common. 展开更多
关键词 than more normal What is intraoperative blood pressure and do deviations from it really affect postoperative outcome IOH
暂未订购
Nonlinear Elastic Constitutive Model of Soil-Structure Interfaces Under Relatively High Normal Stress 被引量:17
4
作者 ZHOU Guo-qing XIA Hong-chun +1 位作者 ZHAO Guang-si ZHOU Jie 《Journal of China University of Mining and Technology》 EI 2007年第3期301-305,共5页
The shear characteristics of soil-structure interfaces with different roughness are studied systematically by us-ing the DRS-1 high normal stress and residual shear apparatus. The experimental results indicate that,un... The shear characteristics of soil-structure interfaces with different roughness are studied systematically by us-ing the DRS-1 high normal stress and residual shear apparatus. The experimental results indicate that,under a relatively high normal stress,normal stress and the coefficient of structural roughness are the most important factors affecting the mechanical interface characteristics. The relationship between shear stress and shear displacement of the soil-structure interface is a hyperbolic curve with high regression accuracy. Based on our experimental results,a nonlinear elastic con-stitutive model of the soil-structure interface under relatively high normal stress is established with a definite physical meaning for its parameters. The model can predict the strain hardening behavior of the soil during the shearing process. The results show an encouraging agreement with experimental data from direct shear tests. 展开更多
关键词 high normal stress standard medium sand INTERFACE strain hardening constitutive model
在线阅读 下载PDF
DELIBERATlON TO THE DEFINITION OF TOOTH THICKNESS FOR INVOLUTE HELICAL GEAR IN INTERNATIONAL STANDARD ISO1122/1
5
作者 Yang Guoling Chen MinLi Xianming Hu Guangxing Feng Shenghua Li Baosong(Shenyang Institute of Gold Technology)( Shenyang Centre of Robot) 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 1995年第3期187-202,共17页
The definitions of the normal chordal tooth thichness and the constant chord in interna-tional standard ISO 1122/1-1983(E) are analyzed according to the basic principle of involute cy-lindrical gear geometry. It is po... The definitions of the normal chordal tooth thichness and the constant chord in interna-tional standard ISO 1122/1-1983(E) are analyzed according to the basic principle of involute cy-lindrical gear geometry. It is pointed out that in the case of spur gears, the two definitions arerespectively identical with generally recognized traditional formulas, but in the case of helical gears,they are respectively contradictory with their traditional formulas. The general principle of themethod of the two-point measuring for the tooth thickness of gears is analysized, and the calcula-tion formulas of the two-point measuring for the tooth thickness of the involute helical gear ispresented. It is proved theoretically that a constant chord can be measured with the method of thetwo-point measuring (with the tooth thickness caliper) while normal chordal tooth thickness cannot be measured with the tooth thickness caliper (the method of the two-point measuring). The is-sues of the two definitions of the tooth thickness in the international standard are analysed outagain in measurng. 展开更多
关键词 International standard normal chordal tooth thickness Constant chordMeasurement of tooth thickness
全文增补中
Abnormal Behavior Detection and Recognition Method Based on Improved ResNet Model 被引量:5
6
作者 Huifang Qian Mengmeng Zheng Xuan Zhou 《Computers, Materials & Continua》 SCIE EI 2020年第12期2153-2167,共15页
The core technology in an intelligent video surveillance system is that detecting and recognizing abnormal behaviors timely and accurately.The key breakthrough point in recognizing abnormal behaviors is how to obtain ... The core technology in an intelligent video surveillance system is that detecting and recognizing abnormal behaviors timely and accurately.The key breakthrough point in recognizing abnormal behaviors is how to obtain the effective features of the picture,so as to solve the problem of recognizing them.In response to this difficulty,this paper introduces an adjustable jump link coefficients model based on the residual network.The effective coefficients for each layer of the network can be set after using this model to further improving the recognition accuracy of abnormal behavior.A convolution kernel of 1×1 size is added to reduce the number of parameters for the purpose of improving the speed of the model in this paper.In order to reduce the noise of the data edge,and at the same time,improve the accuracy of the data and speed up the training,a BN(Batch Normalization)layer is added before the activation function in this network.This paper trains this network model on the public ImageNet dataset,and then uses the transfer learning method to recognize these abnormal behaviors of human in the UTI behavior dataset processed by the YOLO_v3 target detection network.Under the same experimental conditions,compared with the original ResNet-50 model,the improved model in this paper has a 2.8%higher accuracy in recognition of abnormal behaviors on the public UTI dataset. 展开更多
关键词 ResNet abnormal behavior recognition YOLO_v3 adjustable jump link coefficients model standard normal distribution
在线阅读 下载PDF
IL-28B polymorphisms and treatment response in hepatitis C virus patients with persistently normal alanine aminotransferase 被引量:2
7
作者 Tatsuo Miyamura Tatsuo Kanda +7 位作者 Masato Nakamura Xia Jiang Shuang Wu Shingo Nakamoto Shigeru Mikami Nobuo Takada Fumio Imazeki Osamu Yokosuka 《World Journal of Hepatology》 CAS 2013年第11期635-641,共7页
AIM:To examine the association between the interleukin 28B(IL-28B)genotype and treatment response in hepatitis C virus(HCV)-infected patients with persistently normal alanine aminotransferase(PNALT).METHODS:We compare... AIM:To examine the association between the interleukin 28B(IL-28B)genotype and treatment response in hepatitis C virus(HCV)-infected patients with persistently normal alanine aminotransferase(PNALT).METHODS:We compared the treatment response of HCV-infected patients with PNALT to that of patients with non-PNALT.Between February 2010 and April2013,278 patients infected with HCV were enrolled in this study.All of the patients were treated with peginterferon-alpha 2a or 2b plus ribavirin.In addition,180μg of peginterferon alpha-2a or 1.5μg/kg peginterferon alpha-2b per week plus weight-based ribavirin(600-1000 mg/d)were typically administered for 24 wk to HCV genotype 2-infected patients or for 48-72 wk to HCV genotype 1-infected patients.In all of the patients,the IL-28B rs8099917 genotype was determined using a TaqMan single-nucleotide polymorphism assay.HCV RNA was measured using the COBAS TaqMan HCV test.RESULTS:Female patients were dominant in the PNALT group(P【0.0001).Among 72 HCV genotype 1-infected patients with PNALT,the early virologic response(EVR)rates(P【0.01)and the sustained virologic response(SVR)rates(P【0.01)were higher in patients with the IL-28B TT genotype than in those with the IL-28B TG/GG genotype.In HCV genotype 1-infected patients with PNALT,multivariate logistic-regression analysis showed that SVR was independently predicted by the IL-28B rs8099917 TT type(P【0.05)and having an EVR(P【0.01).The IL-28B rs8099917 TT genotype strongly correlated with treatment response in HCV genotype 1-infected Asian patients with PNALT.CONCLUSION:The IL-28B genotype may be useful for selecting HCV genotype 1-infected patients with PNALT who should receive interferon-based treatment. 展开更多
关键词 HEPATITIS C virus INTERLEUKIN 28B Persistent normal ALANINE AMINOTRANSFERASE levels standard of care Treatment response
暂未订购
Self-normalization:Taming a wild population in a heavy-tailed world 被引量:2
8
作者 SHAO Qi-man ZHOU Wen-xin 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2017年第3期253-269,共17页
The past two decades have witnessed the active development of a rich probability theory of Studentized statistics or self-normalized processes, typified by Student’s t-statistic as introduced by W. S. Gosset more tha... The past two decades have witnessed the active development of a rich probability theory of Studentized statistics or self-normalized processes, typified by Student’s t-statistic as introduced by W. S. Gosset more than a century ago, and their applications to statistical problems in high dimensions, including feature selection and ranking, large-scale multiple testing and sparse, high dimensional signal detection. Many of these applications rely on the robustness property of Studentization/self-normalization against heavy-tailed sampling distributions. This paper gives an overview of the salient progress of self-normalized limit theory, from Student’s t-statistic to more general Studentized nonlinear statistics. Prototypical examples include Studentized one- and two-sample U-statistics. Furthermore, we go beyond independence and glimpse some very recent advances in self-normalized moderate deviations under dependence. 展开更多
关键词 Berry-Esseen inequality Hotelling’s T 2-statistic large deviation moderate deviation SELF-normalIZATION Student’s t-statistic U-STATISTIC
在线阅读 下载PDF
Trends in Vegetation Response to Drought in Sudano-Sahelian Part of Northern Nigeria 被引量:1
9
作者 Blessing Bolarinwa Fabeku Emmanuel C. Okogbue 《Atmospheric and Climate Sciences》 2014年第4期569-588,共20页
This study was carried out to evaluate the drought occurrence and its implication on vegetation cover over the Sudano-Sahelian zone of the Northern part of Nigeria. Monthly mean Rainfall data for the period 40 years (... This study was carried out to evaluate the drought occurrence and its implication on vegetation cover over the Sudano-Sahelian zone of the Northern part of Nigeria. Monthly mean Rainfall data for the period 40 years (1971-2010) were obtained from Nigeria Meteorological Agency (NIMET) for each of the meteorological stations present and functioning in this region for climatic analysis. Standardized Precipitation Index (SPI) was used to analyze drought occurrence on a time scale of five (5) months that cover the period of raining season over the study area. Also Satellite data over the selected part of the study area for three different epochs, 1986, 2000 and 2005 were used for vegetation response analysis. The SPI values were interpolated using Inverse Distance Weighted (IDW) interpolation technique in ArcGIS 9.3 to generate Drought Spatial Pattern Map for each selected modeled years. The vegetation response indicators used are land cover maps and Greenness Index (GI) maps. Land cover categories were classified into five levels: Dense Vegetation, less dense Vegetation, Settlement/built up, Bare Surface and Water body. The results based on the ground truth (rainfall) data show that many years of drought episode were experienced over the study area. On the other hand, the prime indicators (Land cover and GI maps) used in this study also depicts the changes that took place over the study area in response to this climatic anomaly (drought) and it could be noted that there was dramatic reduction in the occurrence towards the end of the last two decade, 1990-1999, which simply indicated improvement in rainfall even in 2000 and the later years. 展开更多
关键词 DROUGHT OCCURRENCE VEGETATION RESPONSE standardize PRECIPITATION INDEX (SPI) normalized PRECIPITATION INDEX (NDVI) Greenness INDEX (GI) DROUGHT Spatial Map
暂未订购
Visible and Near-Infrared Spectroscopic Discriminant Analysis Applied to Identification of Soy Sauce Adulteration 被引量:1
10
作者 Chunli Fu Jiemei Chen +1 位作者 Lifang Fang Tao Pan 《American Journal of Analytical Chemistry》 2022年第2期51-62,共12页
The identification of soy sauce adulteration can avoid fraud, and protect the rights and interests of producers and consumers. Based on two measurement models (1 mm, 10 mm), the visible and near-infrared (Vis-NIR) spe... The identification of soy sauce adulteration can avoid fraud, and protect the rights and interests of producers and consumers. Based on two measurement models (1 mm, 10 mm), the visible and near-infrared (Vis-NIR) spectroscopy combined with standard normal variate-partial least squares-discriminant analysis (SNV-PLS-DA) was used to establish the discriminant analysis models for adulterated and brewed soy sauces. Chubang soy sauce was selected as an identification brand (negative, 70). The adulteration samples (positive, 72) were prepared by mixing Chubang soy sauce and blended soy sauce with different adulteration rates. Among them, the “blended soy sauce” sample was concocted of salt water (NaCl), monosodium glutamate (C<sub>5</sub>H<sub>10</sub>NNaO<sub>5</sub>) and caramel color (C<sub>6</sub>H<sub>8</sub>O<sub>3</sub>). The rigorous calibration-prediction-validation sample design was adopted. For the case of 1 mm, five waveband models (visible, short-NIR, long-NIR, whole NIR and whole scanning regions) were established respectively;in the case of 10 mm, three waveband models (visible, short-NIR and visible-short-NIR regions) for unsaturated absorption were also established respectively. In independent validation, the models of all wavebands in the cases of 1 mm and 10 mm have achieved good discrimination effects. For the case of 1 mm, the visible model achieved the optimal validation effect, the validation recognition-accuracy rate (RAR<sub>V</sub>) was 99.6%;while in the case of 10 mm, both the visible and visible-short-NIR models achieved the optimal validation effect (RAR<sub>V</sub> = 100%). The detection method does not require reagents and is fast and simple, which is easy to promote the application. The results can provide valuable reference for designing small dedicated spectrometers with different measurement modals and different spectral regions. 展开更多
关键词 Visible and Near-Infrared Spectroscopy Soy Sauce Adulteration Identification Partial Least Squares-Discriminant Analysis standard normal Variate
在线阅读 下载PDF
Distribution of driving trajectory of passenger car in highway horizontal curves
11
作者 任园园 李显生 +1 位作者 郭伟伟 王吉亮 《Journal of Beijing Institute of Technology》 EI CAS 2012年第2期222-228,共7页
In this paper the track behavior of passenger car was studied. The vehicle driving trajectory and driving direction were defined, and a classification of the type of vehicle trajectories along the curves was developed... In this paper the track behavior of passenger car was studied. The vehicle driving trajectory and driving direction were defined, and a classification of the type of vehicle trajectories along the curves was developed. The statistical parameters of vehicle trajectory samples in free flow and their frequency curves and cumulative frequency curves were achieved, K-S test and chi-square test were used to test normal distribution and gamma distribution for collected sample data, and the probabili- ty density functions were given. At last, dispersion degree between vehicle trajectory random varia- ble and the characteristic value of cumulative frequency curve in each key cross section in curves was analyzied. The proposed conclusion can provide theoretical support for the reasonable optimization of widen curve, design of alignment and the management of counter flow conflicts. 展开更多
关键词 traffic safety vehicle trajectory transverse deviation gamma distribution normal dis-tribution horizontal curve
在线阅读 下载PDF
LIMITING BEHAVIOR OF RECURSIVE M-ESTIMATORS IN MULTIVARIATE LINEAR REGRESSION MODELS AND THEIR ASYMPTOTIC EFFICIENCIES
12
作者 缪柏其 吴月华 刘东海 《Acta Mathematica Scientia》 SCIE CSCD 2010年第1期319-329,共11页
Recursive algorithms are very useful for computing M-estimators of regression coefficients and scatter parameters. In this article, it is shown that for a nondecreasing ul (t), under some mild conditions the recursi... Recursive algorithms are very useful for computing M-estimators of regression coefficients and scatter parameters. In this article, it is shown that for a nondecreasing ul (t), under some mild conditions the recursive M-estimators of regression coefficients and scatter parameters are strongly consistent and the recursive M-estimator of the regression coefficients is also asymptotically normal distributed. Furthermore, optimal recursive M-estimators, asymptotic efficiencies of recursive M-estimators and asymptotic relative efficiencies between recursive M-estimators of regression coefficients are studied. 展开更多
关键词 asymptotic efficiency asymptotic normality asymptotic relative efficiency least absolute deviation least squares M-ESTIMATION multivariate linear optimal estimator reeursive algorithm regression coefficients robust estimation regression model
在线阅读 下载PDF
Binary Gravitational Search based Algorithm for Optimum Siting and Sizing of DG and Shunt Capacitors in Radial Distribution Systems
13
作者 N. A. Khan S. Ghosh S. P. Ghoshal 《Energy and Power Engineering》 2013年第4期1005-1010,共6页
This paper presents a binary gravitational search algorithm (BGSA) is applied to solve the problem of optimal allotment of DG sets and Shunt capacitors in radial distribution systems. The problem is formulated as a no... This paper presents a binary gravitational search algorithm (BGSA) is applied to solve the problem of optimal allotment of DG sets and Shunt capacitors in radial distribution systems. The problem is formulated as a nonlinear constrained single-objective optimization problem where the total line loss (TLL) and the total voltage deviations (TVD) are to be minimized separately by incorporating optimal placement of DG units and shunt capacitors with constraints which include limits on voltage, sizes of installed capacitors and DG. This BGSA is applied on the balanced IEEE 10 Bus distribution network and the results are compared with conventional binary particle swarm optimization. 展开更多
关键词 normal Load Flow Radial Distribution System Distributed Generation SHUNT Capacitors BINARY Particle SWARM Optimization BINARY GRAVITATIONAL SEARCH Algorithm toTAL line Loss toTAL Voltage deviation
在线阅读 下载PDF
Application of Artificial Intelligence Technology in Landscape Architecture Industry 被引量:1
14
作者 QIU Cuiju 《Journal of Landscape Research》 2024年第2期66-68,共3页
With wide application prospects in landscape industry,artificial intelligence technology plays an important role in improving work efficiency,optimizing design,strengthening construction management,and achieving intel... With wide application prospects in landscape industry,artificial intelligence technology plays an important role in improving work efficiency,optimizing design,strengthening construction management,and achieving intelligent maintenance.With the continuous development of technology,the application of artificial intelligence in landscape architecture industry will become more in-depth and extensive,which can provid powerful support for the innovation and development of the industry.It is hoped that the modernization process of the landscape industry can be promoted through the analysis on the application and difficulties of artificial intelligence technology in the landscape industry. 展开更多
关键词 Artificial intelligence Landscape architecture standardIZATION normalIZATION
在线阅读 下载PDF
Modeling and Simulation Study of Space Data Link Protocol
15
作者 Ismail Hababeh Rizik M. H. Al-Sayyed +2 位作者 Ja’far Alqatawna Yousef Majdalawi Marwan Nabelsi 《International Journal of Communications, Network and System Sciences》 2014年第10期440-452,共13页
This research paper describes the design and implementation of the Consultative Committee for Space Data Systems (CCSDS) standards REF _Ref401069962 \r \h \* MERGEFORMAT [1] for Space Data Link Layer Protocol (SDLP). ... This research paper describes the design and implementation of the Consultative Committee for Space Data Systems (CCSDS) standards REF _Ref401069962 \r \h \* MERGEFORMAT [1] for Space Data Link Layer Protocol (SDLP). The primer focus is the telecommand (TC) part of the standard. The implementation of the standard was in the form of DLL functions using C++ programming language. The second objective of this paper was to use the DLL functions with OMNeT++ simulating environment to create a simulator in order to analyze the mean end-to-end Packet Delay, maximum achievable application layer throughput for a given fixed link capacity and normalized protocol overhead, defined as the total number of bytes transmitted on the link in a given period of time (e.g. per second) divided by the number of bytes of application data received at the application layer model data sink. In addition, the DLL was also integrated with Ground Support Equipment Operating System (GSEOS), a software system for space instruments and small spacecrafts especially suited for low budget missions. The SDLP is designed for rapid test system design and high flexibility for changing telemetry and command requirements. GSEOS can be seamlessly moved from EM/FM development (bench testing) to flight operations. It features the Python programming language as a configuration/scripting tool and can easily be extended to accommodate custom hardware interfaces. This paper also shows the results of the simulations and its analysis. 展开更多
关键词 Consultative COMMITTEE for SPACE DATA Systems standards SPACE DATA Link PROtoCOL Mean END-to-END Packet Delay Maximum Achievable Application Layer Throughput normalized PROtoCOL OVERHEAD Telecommand Spacecrafts SPACE Instruments
暂未订购
Seminar focuses on standardized innovative development of cities
16
《China Standardization》 2019年第5期9-9,共1页
Themed on "standards and city: refinement, normalization and quality", the second high-end seminar on national city standardized innovative development was held in Zhengzhou, capital of Central China’s Hena... Themed on "standards and city: refinement, normalization and quality", the second high-end seminar on national city standardized innovative development was held in Zhengzhou, capital of Central China’s Henan province, on July 30. 展开更多
关键词 Themed normalIZATION standardized
原文传递
Characteristics of laser-induced breakdown spectroscopy of liquid slag
17
作者 董长言 于洪霞 +4 位作者 孙兰香 李洋 刘修业 周平 黄少文 《Plasma Science and Technology》 SCIE EI CAS CSCD 2024年第2期86-93,共8页
Rapid online analysis of liquid slag is essential for optimizing the quality and energy efficiency of steel production. To investigate the key factors that affect the online measurement of refined slag using laser-ind... Rapid online analysis of liquid slag is essential for optimizing the quality and energy efficiency of steel production. To investigate the key factors that affect the online measurement of refined slag using laser-induced breakdown spectroscopy(LIBS), this study examined the effects of slag composition and temperature on the intensity and stability of the LIBS spectra. The experimental temperature was controlled at three levels: 1350℃, 1400℃, and 1450℃. The results showed that slag composition and temperature significantly affected the intensity and stability of the LIBS spectra. Increasing the Fe content and temperature in the slag reduces its viscosity, resulting in an enhanced intensity and stability of the LIBS spectra. Additionally, 42 refined slag samples were quantitatively analyzed for Fe, Si, Ca, Mg, Al, and Mn at 1350℃, 1400℃, and 1450℃.The normalized full spectrum combined with partial least squares(PLS) quantification modeling was used, using the Ca Ⅱ 317.91 nm spectral line as an internal standard. The results show that using the internal standard normalization method can significantly reduce the influence of spectral fluctuations. Meanwhile, a temperature of 1450℃ has been found to yield superior results compared to both 1350℃ and 1400℃, and it is advantageous to conduct a quantitative analysis of the slag when it is in a “water-like” state with low viscosity. 展开更多
关键词 laser-induced breakdown spectroscopy(LIBS) SLAG temperature COMPOSITION VISCOSITY internal standard normalization partial least squares(PLS)
在线阅读 下载PDF
Response of remotely sensed Normalized Difference Water Deviation Index to the 2006 Drought of eastern Sichuan Basin 被引量:6
18
作者 ZHANG WenJiang1, LU QiFeng2, GAO ZhiQiang3 & PENG Jian4 1 School of Water Resource and Hydropower, Sichuan University, Chengdu 610065, China 2 National Satellite Meteorological Center, China Meteorological Administration, Beijing 100081, China +1 位作者 3 Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing 100101, China 4 School of Environmental Sciences, Peking University, Beijing 100871, China 《Science China Earth Sciences》 SCIE EI CAS 2008年第5期748-758,共11页
One of the most serious droughts in last century occurred in eastern Sichuan Basin in the summer of 2006 (hereinafter called the Drought). The response of Moderate Resolution Imaging Spectroradiometer (MODIS, boarding... One of the most serious droughts in last century occurred in eastern Sichuan Basin in the summer of 2006 (hereinafter called the Drought). The response of Moderate Resolution Imaging Spectroradiometer (MODIS, boarding on NASA satellites of Terra and Aqua) to the Drought was analyzed in order to reach one practicable monitoring solution for regional soil moisture. Temporal process and spatial extension of the Drought were firstly estimated with ground meteorological and hydrological observations. Then, for the whole region of Sichuan and Chongqing, the remotely sensed Normalized Difference Water In- dex (NDWI) for the summers of 2001―2006 were calculated based on 8-day composite MODIS products, which were further used to construct a new water index (Normalized Difference Water Deviation Index, NDWDI) to examine the sensitivity of remote sensing in the Drought. The study showed that the NDWDI is more sensitive to regional drought than other absolute-soil-moisture-based indices. With the new index, the study extracted the spatial-temporal characteristics of the 2006 Drought, and explored its developing and withdrawing processes, which agreed with related statistics. Compared with ground method of drought observation, the NDWDI-based remote sensing solution of this paper is more pref- erable and practicable in that the local soil properties of water consumption and supply are implicitly taken into account, and the spatial representativity limit of ground observation is circumvented to a degree as satellite remotely senses the earth surface in a way of two-dimensional pixel matrix. So, the NDWDI-based method can be used to monitor regional soil water stress situation more practically and efficiently. 展开更多
关键词 SICHUAN Basin DROUGHT normalized DIFFERENCE WATER deviation INDEX RESPONSE of remote sensing regional scale
原文传递
轨道交通行车作业标准化与规范化在教学中的渗透路径研究
19
作者 吴婷 《中国标准化》 2025年第8期217-219,共3页
轨道交通行车作业应当坚守标准与规范,进而确保高效、高质和安全。作为轨道交通运营管理专业的教师,应当在教学中积极渗透轨道交通行车作业标准化和规范化的要求,增强学生对轨道交通行车作业标准化和规范化的认识,从而在日后从业过程中... 轨道交通行车作业应当坚守标准与规范,进而确保高效、高质和安全。作为轨道交通运营管理专业的教师,应当在教学中积极渗透轨道交通行车作业标准化和规范化的要求,增强学生对轨道交通行车作业标准化和规范化的认识,从而在日后从业过程中贯彻落实。本文基于此展开研究,从标准化和规范化要求分析入手,结合教学经验,寻求渗透方法。 展开更多
关键词 轨道交通 行车作业 标准化 规范化 教学方法
在线阅读 下载PDF
上一页 1 2 51 下一页 到第
使用帮助 返回顶部