期刊文献+
共找到147篇文章
< 1 2 8 >
每页显示 20 50 100
基于信差的我国绿色债券定价影响因素分析
1
作者 汤昊 《中文科技期刊数据库(全文版)经济管理》 2023年第2期128-132,共5页
根据国家印发文件《绿色债券支持项目目录(2021年版)》中的定义,绿色债券是满足发行透明、环保承诺等条件,将募集资金专门用于支持符合规定条件的绿色产业、绿色项目或绿色经济活动,依照法定程序发行并按约定还本付息的有价证券。中国于... 根据国家印发文件《绿色债券支持项目目录(2021年版)》中的定义,绿色债券是满足发行透明、环保承诺等条件,将募集资金专门用于支持符合规定条件的绿色产业、绿色项目或绿色经济活动,依照法定程序发行并按约定还本付息的有价证券。中国于2015年首次引进绿色金融理念。2015年7月16日,新疆金凤科技股份有限公司在香港联交所发行了首单永续绿色债券,同时在海外完成3亿美元债券的发行,票面利率2.5%,期限3年,并由国际专业第三方风险管理服务机构DNV认证,成为中资企业发行的首个绿色债券。同年国家发改委印发的一系列规范文件提出了我国现阶段发行绿色债券的要求,标志着绿色债券在中国的正式开端,从此我国绿色债券市场蓬勃发展。根据《中国绿色债券市场报告2021》,截止至2021年底中国在境内外市场累计发行贴标绿色债券3,270亿美元(约2.1万亿元人民币),按符合CBI定义的绿色债券累计发行量,中国是仅次于美国(3055亿美元)的全球第二大绿色债券市场。 展开更多
关键词 绿色债券 定价因素 信差
下载PDF
佉卢文书所见鄯善国信差职责初探 被引量:2
2
作者 张婧 《西域研究》 CSSCI 北大核心 2018年第4期11-14,M0004,共5页
新疆出土的佉卢文书多为反映鄯善国政治、经济的资料,在已经解读的七百多件佉卢文书中有不少文书提到鄯善国的信差。从文书内容看,信差为西域邮驿中的工作人员,他们在城邦国家之间,特别是在城邦国家内部的沟通方面作用重大。西域信差的... 新疆出土的佉卢文书多为反映鄯善国政治、经济的资料,在已经解读的七百多件佉卢文书中有不少文书提到鄯善国的信差。从文书内容看,信差为西域邮驿中的工作人员,他们在城邦国家之间,特别是在城邦国家内部的沟通方面作用重大。西域信差的职责不但包括将国王政令送达地方政府,而且包括将地方官员的报告书呈递至王廷,还包括对私人信件的递送和礼物、粮食的运送以及流民押送,可见鄯善国的信差对当地信息的沟通十分关键。 展开更多
关键词 佉卢文书 鄯善国 信差 职责
原文传递
仙子的小信差
3
作者 乔栩桐 《快乐童话》 2010年第11期27-28,共2页
听说童话山的曹湾姐姐老家就在山西。那我可就是她的小老乡了。我最大的愿望就是当一个小作家,写出许许多多优美的文章。和善、稳重、大方、的我,最开心的时候就是和我的朋友们在一起了。
关键词 小学 作文 语文教学 《仙子的小信差
原文传递
Integrative analysis of bone-formation associated genes and immune cell infiltration in osteoporosis, and the prediction of active ingredients in targeted traditional Chinese medicine
4
作者 WANG Kai DONG Ping GUO Hongzhang 《Digital Chinese Medicine》 CAS CSCD 2024年第2期160-170,共11页
Objective To explore the differential expression and mechanisms of bone formation-related genes in osteoporosis(OP)leveraging bioinformatics and machine learning methodologies;and to predict the active ingredients of ... Objective To explore the differential expression and mechanisms of bone formation-related genes in osteoporosis(OP)leveraging bioinformatics and machine learning methodologies;and to predict the active ingredients of targeted traditional Chinese medicine(TCM)herbs.Methods The Gene Expression Omnibus(GEO)and GeneCards databases were employed to conduct a comprehensive screening of genes and disease-associated loci pertinent to the pathogenesis of OP.The R package was utilized as the analytical tool for the identification of differentially expressed genes.Least absolute shrinkage and selection operator(LASSO)logis-tic regression analysis and support vector machine-recursive feature elimination(SVM-RFE)algorithm were employed in defining the genetic signature specific to OP.Gene Ontology(GO)and Kyoto Encyclopedia of Genes and Genomes(KEGG)pathway enrichment analyses for the selected pivotal genes were conducted.The cell-type identification by estimating rela-tive subsets of RNA transcripts(CIBERSORT)algorithm was leveraged to examine the infiltra-tion patterns of immune cells;with Spearman’s rank correlation analysis utilized to assess the relationship between the expression levels of the genes and the presence of immune cells.Coremine Medical Database was used to screen out potential TCM herbs for the treatment of OP.Comparative Toxicogenomics Database(CTD)was employed for forecasting the TCM ac-tive ingredients targeting the key genes.AutoDock Vina 1.2.2 and GROMACS 2020 softwares were employed to conclude analysis results;facilitating the exploration of binding affinity and conformational dynamics between the TCM active ingredients and their biological targets.Results Ten genes were identified by intersecting the results from the GEO and GeneCards databases.Through the application of LASSO regression and SVM-RFE algorithm;four piv-otal genes were selected:coat protein(CP);kallikrein 3(KLK3);polymeraseγ(POLG);and transient receptor potential vanilloid 4(TRPV4).GO and KEGG pathway enrichment analy-ses revealed that these trait genes were predominantly engaged in the regulation of defense response activation;maintenance of cellular metal ion balance;and the production of chemokine ligand 5.These genes were notably associated with signaling pathways such as ferroptosis;porphyrin metabolism;and base excision repair.Immune infiltration analysis showed that key genes were highly correlated with immune cells.Macrophage M0;M1;M2;and resting dendritic cell were significantly different between groups;and there were signifi-cant differences between different groups(P<0.05).The interaction counts of resveratrol;curcumin;and quercetin with KLK3 were 7;3;and 2;respectively.It shows that the interac-tions of resveratrol;curcumin;and quercetin with KLK3 were substantial.Molecular docking and molecular dynamics simulations further confirmed the robust binding affinity of these bioactive compounds to the target genes.Conclusion Pivotal genes including CP;KLK3;POLG;and TRPV4;exhibited commendable significant prognostic value;and played a crucial role in the diagnostic assessment of OP.Resveratrol;curcumin;and quercetin;natural compounds found in TCM;showed promise in their potential to effectively modulate the bone-forming gene KLK3.This study provides a sci-entific basis for the interpretation of the pathogenesis of OP and the development of clinical drugs. 展开更多
关键词 OSTEOPOROSIS Bone formation Differentially expressed genes Biological information Traditional Chinese medicine(TCM) Active ingredients Molecular mechanism
下载PDF
基于MEMS三轴加速度传感器的摔倒检测 被引量:56
5
作者 刘鹏 卢潭城 +2 位作者 吕愿愿 邓永莉 陆起涌 《传感技术学报》 CAS CSCD 北大核心 2014年第4期570-574,共5页
摔倒作为人体活动的一部分,是影响人体健康的一大因素,尤其对病人和老年人而言,摔倒检测至关重要。基于MEMS三轴加速度传感器采集的人体活动加速度信号,提出了一种基于固定阈值的信号幅度向量滑动平均法SVMSA。该方法根据人体活动时的... 摔倒作为人体活动的一部分,是影响人体健康的一大因素,尤其对病人和老年人而言,摔倒检测至关重要。基于MEMS三轴加速度传感器采集的人体活动加速度信号,提出了一种基于固定阈值的信号幅度向量滑动平均法SVMSA。该方法根据人体活动时的加速度信号特征,利用预先设定的阈值对加速度信号幅度向量SVM的滑动平均SVMSA进行判决,同时使用差分信号幅度域DSMA区分快速跑步等剧烈运动,准确实现了人体的摔倒检测。主要优势在于分析并区别了人体快速跑步等剧烈运动对摔倒检测的影响。通过对8位实验者的测试,该算法实现了94.4%的精确度。实验表明该算法能够较为准确地实现人体的摔倒检测。 展开更多
关键词 传感器应用 摔倒检测 三轴加速度传感器
下载PDF
基于多尺度低秩模型的心脏磁共振成像方法研究
6
作者 蒋明峰 陆雨 +2 位作者 朱志军 徐文龙 汪亚明 《电子学报》 EI CAS CSCD 北大核心 2017年第9期2218-2224,共7页
本文提出一种基于多尺度低秩模型(MSL,Multi-Scale Low rank)的磁共振成像方法,该方法将矩阵分解成多尺度的块低秩矩阵之和,并将多尺度块低秩矩阵之和的最小化作为约束条件用于磁共振成像.两种不同的心脏磁共振数据用于验证本文所提出... 本文提出一种基于多尺度低秩模型(MSL,Multi-Scale Low rank)的磁共振成像方法,该方法将矩阵分解成多尺度的块低秩矩阵之和,并将多尺度块低秩矩阵之和的最小化作为约束条件用于磁共振成像.两种不同的心脏磁共振数据用于验证本文所提出算法重构磁共振成像的精度.实验结果表明,相比于k-t SLR(k-t Sparsity Low Rank)和L+S(Low Rank plus Sparse)方法,所提出的MSL方法具有更好的重建效果,获得更高的重构信差比(signal to error ratio),并具有更好地结构相似性,但需要更长的重构时间. 展开更多
关键词 磁共振图像重构 多尺度低秩 信差
下载PDF
Lower bound on BER performance for maximal ratio combining with weighting errors 被引量:1
7
作者 盛彬 尤肖虎 《Journal of Southeast University(English Edition)》 EI CAS 2005年第4期379-384,共6页
The theoretical lower bounds on mean squared channel estimation errors for typical fading channels are presented by the infinite-length and non-causal Wiener filter and the exact closed-form expressions of the lower b... The theoretical lower bounds on mean squared channel estimation errors for typical fading channels are presented by the infinite-length and non-causal Wiener filter and the exact closed-form expressions of the lower bounds for different channel Doppler spectra are derived. Based on the obtained lower bounds on mean squared channel estimation errors, the limits on bit error rate (BER) for maximal ratio combining (MRC) with Gaussian distributed weighting errors on independent and identically distributed (i. i. d) fading channels are presented. Numerical results show that the BER performances of ideal MRC are the lower bounds on the BER performances of non-ideal MRC and deteriorate as the maximum Doppler frequency increases or the SNR of channel estimate decreases. 展开更多
关键词 lower bound bit error rate minimum mean-square error channel estimation maximal ratio combining
下载PDF
Multi-dimensional Analysis on Regional Land Use——Taking Bijie City as an Example
8
作者 陈笑筑 张定义 文兴耀 《Agricultural Science & Technology》 CAS 2016年第4期1002-1007,共6页
Based on the theory of information entropy, time series and spatial variation of land use changes of Bijie City in 2009-2013 were analyzed from different dimensions such as land use degree and land use diversity. The ... Based on the theory of information entropy, time series and spatial variation of land use changes of Bijie City in 2009-2013 were analyzed from different dimensions such as land use degree and land use diversity. The result showed that in 2009-2013, the forest vegetation was well protected, and the construction land was under reasonable expansion under the influence of economic development, the land use degree of which developed gradually to width and depth, and the trend of information entropy showed a graduate increase, indicating that land use scale became more reasonable and the area of different land type became more balanced in Bijie in the period. The study results showed that land resources in Bijie City were used rationally under the strategy from central government local government,and Bijie was in the benign development of economic development—resource distribution—scale change. Moreover, Bijie chould further improve land use pattern such as redevelop stock construction land, optimize the industrial land use pattern and mountain agricultural land development in the future. 展开更多
关键词 Land use Diversity index Information entropy Regional differences Dynamic changes
下载PDF
谈谈我厂规避坏账风险的做法
9
作者 单越钟 《冶金财会》 1999年第3期23-24,共2页
销售是企业生产经营成果的实现过程,从资金运动过程看,是从成品资金转化为货币资金的过程。这一过程有时候是从成品资金直接转化为货币资金,即销售时钱货两清;有时候则分为两个阶段,先从成品资金转化为结算资金,形成应收账款,然后再从... 销售是企业生产经营成果的实现过程,从资金运动过程看,是从成品资金转化为货币资金的过程。这一过程有时候是从成品资金直接转化为货币资金,即销售时钱货两清;有时候则分为两个阶段,先从成品资金转化为结算资金,形成应收账款,然后再从结算资金转化为货币资金,收回应收账款。目前。 展开更多
关键词 坏账风险 应收账款 货款回收 成品资金 结算方式 货币资金 结算资金 销售人员 信差 商业折扣
下载PDF
Flow Regime Identification of Gas-liquid Two-phase Flow Based on HHT 被引量:11
10
作者 孙斌 张宏建 +1 位作者 程路 赵玉晓 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2006年第1期24-30,共7页
A new method to identify flow regime in two-phase flow was presented, based on signal processing of differential pressure using Hilbert Huang transform (HHT). Signals obtained from a Venturi meter were decomposed in... A new method to identify flow regime in two-phase flow was presented, based on signal processing of differential pressure using Hilbert Huang transform (HHT). Signals obtained from a Venturi meter were decomposed into different intrinsic mode functions (IMFs) with HHT, then the energy fraction of each intrinsic mode and the mean value of residual function were calculated, from which the rules of flow regime identification were summarized. Experiments were carried out on two-phase flow in the horizontal tubes with 50mm and 40mm inner diameter, while water flowrate was in the range of 1.3m^3.h^-1 to 10.5m^3.h^-1, oil flowrate was from 4.2m^3.h^-1 to 7.0m^3.h^-1 and gas flowrate from 0 to 15m^3.h^-1. The results show that the proposed rules have high precision for single phase, bubbly, and slug, plug flow regirne identification, which are independent of not only properties of two-phase fluid. In addition, the method can meet the need of industrial application because of its simple calculation. 展开更多
关键词 flow regime Hilbert-Huang transform differential pressure signal intrinsic mode function gas-liquid two-phase flow
下载PDF
A 0.18μm Transmitter and Receiver with High Speed and Low Power
11
作者 张锋 冯伟 +3 位作者 崔浩 杨袆 黄令仪 胡伟武 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2008年第5期836-840,共5页
This paper describes the design of a low voltage differential signal (LVDS) transmitter and receiver with high speed and low power for CPU, LCD, FPGA, and other fast links. In the proposed transmitter, a stable refe... This paper describes the design of a low voltage differential signal (LVDS) transmitter and receiver with high speed and low power for CPU, LCD, FPGA, and other fast links. In the proposed transmitter, a stable reference and a common mode feedback circuit are integrated into the LVDS drivers, which enable the transmitter to tolerate variations of process, temperature, and supply voltage. The proposed receiver implements a rail-to-rail amplifier architecture that allows a 1.6Gb/s transmission. The transmitter and receiver are implemented in HJ TC 3.3V,0. 18μm CMOS technology. The experimental results demonstrate that the transmitter and receiver reach 1.6Gb/s. The transmitter and receiver pad cells exhibit a power consumption of 35 and 6mW,respectively. 展开更多
关键词 LVDS rail to rail low power
下载PDF
PCCC for the performance improvement of the wireless optical communication system 被引量:2
12
作者 REN Rui-xiang LI Xiao-feng LIN Mi 《Optoelectronics Letters》 EI 2006年第2期133-135,共3页
In wireless optical communication, effects of scintillation make average Bit Error Rate (BER) deteriorate. To improve system performance,PCCC (Parallel Concatenated Convolutional Code) encoding scheme is employed,... In wireless optical communication, effects of scintillation make average Bit Error Rate (BER) deteriorate. To improve system performance,PCCC (Parallel Concatenated Convolutional Code) encoding scheme is employed,and upper bound on the bit error rate is given by considering the effects of scintillation,APD noise and thermal noise. Simulation results show that the POOC encoding scheme can relieve turbulenceinduced intensity fluctuations and the system performance is improved remarkably. 展开更多
关键词 无线通信 光学通信系统 PCCC 误差率
下载PDF
SUBSPACE-BASED NOISE VARIANCE AND SNR ESTIMATION FOR MIMO OFDM SYSTEMS 被引量:1
13
作者 Xu Xiaodong Jing Ya +1 位作者 Zhao Junhui You Xiaohu 《Journal of Electronics(China)》 2006年第2期176-180,共5页
This paper proposes a subspace-based noise variance and Signal-to-Noise Ratio (SNR) estimation algorithm for Multi-Input Multi-Output (MIMO) wireless Orthogonal Frequency Division Multiplexing (OFDM) systems. The spec... This paper proposes a subspace-based noise variance and Signal-to-Noise Ratio (SNR) estimation algorithm for Multi-Input Multi-Output (MIMO) wireless Orthogonal Frequency Division Multiplexing (OFDM) systems. The special training sequences with the property of orthogonality and phase shift orthogonality are used in pilot tones to obtain the estimated channel correlation matrix. Partitioning the observation space into a delay subspace and a noise subspace, we achieve the measurement of noise variance and SNR. Simulation results show that the proposed estimator can obtain accurate and real-time measurements of the noise variance and SNR for various multipath fading channels, demonstrating its strong robustness against different channels. 展开更多
关键词 Multi-Input Multi-Output (MIMO) Orthogonal Frequency Division Multiplexing (OFDM) Noise variance Signal-to-Noise Ratio (SNR) Delay subspace Channel correlation matrix
下载PDF
Analysis of signal-obtaining error factor of sensor in gyro 被引量:5
14
作者 LIU Jian-feng YUAN Gan-nan ZHAO Shi-jun 《Journal of Marine Science and Application》 2005年第2期28-33,共6页
The digital signal-obtaining for gyroscope is given. The single optic-fiber sensor via modulating intensity of light is used as measuring eonlponent . The influence on static transmission properties resulting from the... The digital signal-obtaining for gyroscope is given. The single optic-fiber sensor via modulating intensity of light is used as measuring eonlponent . The influence on static transmission properties resulting from the special working environnlent (e. g. cryogenic and vacuum) ,the measure error because of tile reflector shape of rotor,the abnormity of facula from sensor caused by the existence of engraving error,and tile fixing error of sensor and the error of machine tool's initial lignnlent are investigated. The mathematic model in every condition is founded, the simulation and relative experiments ale done and the outeome is analyzed. The mathematic model and method of compensating technology are studied and some relative experiments are made. The result of study is usefid to improvement of the signal-obtaining system. 展开更多
关键词 fiber-optic sensor signal-obtaining for gyrn cryogenic and vacuum measure error
下载PDF
The design of adaptive sigma-delta A/D converter 被引量:1
15
作者 冯晖 Lin Zhenghui 《High Technology Letters》 EI CAS 2005年第4期367-370,共4页
The signal to noise ratio (SNR) of conventional sigma delta analog to digital converter (∑△ADC) reduces with input signal strength. The existing concept of adaptive quantization is applied to the design of ∑△A... The signal to noise ratio (SNR) of conventional sigma delta analog to digital converter (∑△ADC) reduces with input signal strength. The existing concept of adaptive quantization is applied to the design of ∑△ADC to improve SNR with high dynamic range. An adaptive algorithm and its circuit implementation is proposed. Because of the error due to the circuit implementation, an error self-calibration circuit is also designed. Simulation results indicate that SNR can he nearly independent of the signal strength. 展开更多
关键词 SIGMA-DELTA A/D ADAPTIVE ERROR SELF-CALIBRATION
下载PDF
No-relationship Between Impossibility of Faster-Than-Light Quantum Communication and Distinction of Ensembles with the Same Density Matrix 被引量:1
16
作者 WANG Chuan LONG Gui-Lu SUN Yang 《Communications in Theoretical Physics》 SCIE CAS CSCD 2005年第4X期622-624,共3页
It has been claimed in the literature that impossibility of faster-than-light quantum communication has an origin of indistinguishability of ensembles with the same density matrix. We show that the two concepts are no... It has been claimed in the literature that impossibility of faster-than-light quantum communication has an origin of indistinguishability of ensembles with the same density matrix. We show that the two concepts are not related.We argue that even with an ideal single-atom-precision measurement, it is generally impossible to produce two ensembles with exactly the same density matrix; or to produce ensembles with the same density matrix, classical communication is necessary. Hence the impossibility of faster-than-light communication does not imply the indistinguishability of ensembles with the same density matrix. 展开更多
关键词 faster-than-light communication distinction of ensembles density matrix
下载PDF
Comparison of six statistical approaches in the selection of appropriate fish growth models 被引量:6
17
作者 朱立新 李丽芳 梁振林 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2009年第3期457-467,共11页
The performance of six statistical approaches,which can be used for selection of the best model to describe the growth of individual fish,was analyzed using simulated and real length-at-age data.The six approaches inc... The performance of six statistical approaches,which can be used for selection of the best model to describe the growth of individual fish,was analyzed using simulated and real length-at-age data.The six approaches include coefficient of determination(R2),adjusted coefficient of determination(adj.-R2),root mean squared error(RMSE),Akaike's information criterion(AIC),bias correction of AIC(AICc) and Bayesian information criterion(BIC).The simulation data were generated by five growth models with different numbers of parameters.Four sets of real data were taken from the literature.The parameters in each of the five growth models were estimated using the maximum likelihood method under the assumption of the additive error structure for the data.The best supported model by the data was identified using each of the six approaches.The results show that R2 and RMSE have the same properties and perform worst.The sample size has an effect on the performance of adj.-R2,AIC,AICc and BIC.Adj.-R2 does better in small samples than in large samples.AIC is not suitable to use in small samples and tends to select more complex model when the sample size becomes large.AICc and BIC have best performance in small and large sample cases,respectively.Use of AICc or BIC is recommended for selection of fish growth model according to the size of the length-at-age data. 展开更多
关键词 growth model model selection statistical approach Akalke's information criterion Bayesian information criterion
下载PDF
Precise Background Noise Power Estimate for Echo Cancellation 被引量:2
18
作者 Wen Haoxiang Lai Xiaohan Chen Longdao 《China Communications》 SCIE CSCD 2012年第11期98-106,共9页
The reconstruction of background noise from an error signal of an adaptive filter is a key issue for developing Variable Step-Size Normalized Least Mean Square (VSS-NLMS) algorithm in the context of Echo Cancellation ... The reconstruction of background noise from an error signal of an adaptive filter is a key issue for developing Variable Step-Size Normalized Least Mean Square (VSS-NLMS) algorithm in the context of Echo Cancellation (EC). The core parameter in this algorithm is the Background Noise Power (BNP); in the estimation of BNP, the power difference between the desired signal and the filter output, statistically equaling to the error signal power, has been widely used in a rough manner. In this study, a precise BNP estimate is implemented by multiplying the rough estimate with a corrective factor, taking into consideration the fact that the error signal consists of background noise and misalignment noise. This corrective factor is obtained by subtracting half of the latest VSS value from 1 after analyzing the ratio of BNP to the misalignment noise. Based on the precise BNP estimate, the PVSS-NLMS algorithm suitable for the EC system is eventually proposed. In practice, the proposed algorithm exhibits a significant advantage of easier controllability application, as prior knowledge of the EC environment can be neglected. The simulation results support the preciseness of the BNP estimation and the effectiveness of the proposed algorithm. 展开更多
关键词 adaptive algorithm EC BNP estimate VSS-NLMS algorithm
下载PDF
Measuring Spatial Differences of Informatization in China 被引量:2
19
作者 SONG Zhouying LIU Weidong +2 位作者 MA Li Michael DUNFORD 《Chinese Geographical Science》 SCIE CSCD 2014年第6期717-731,共15页
As the wide application of new Information and Communication Technologies (ICTs) shows, the world is moving fast to- wards an information age. Since China was first connected to the Internet in 1994, the development... As the wide application of new Information and Communication Technologies (ICTs) shows, the world is moving fast to- wards an information age. Since China was first connected to the Internet in 1994, the development of ICTs in China and around the world has been astonishingly fast, and yet there is a clear 'digital divide' among different regions in China. Although Chinese geogra- phers have paid attention to regional differences in informatization, they usually employ a limited number of indicators, mainly focusing on the Intemet. In fact, infi^rmatization is a much broader concept, covering not only the lntemet, but also mobile phones as well as user ability. In the light of these considerations, this study provides a comprehensive examination of the development of informatization and its spatial differences in China. First, based on a literature review, the paper identifies 29 preliminary indicators for measuring informa- tization, and employs prin,-ipal components analysis and the fuzzy analytic hierarchy process to streamline them into 12 indicators to form an ICTs Developmen: Index (ID1). Second, by using the data from provincial statistical yearbooks and the China Internet Network Information Center, the paper calculates the 1191 of each mega-region and each province in 2000-2010, and measures the changing spa- tial differences in the development of informatization in China. Lastly, the paper quantifies the relationship between informatization and economic growth. The empirical results show that the IDI of the western and central China has been increasing faster than that of the coastal region, indicating that the digital divide in China has been narrowing. 展开更多
关键词 informatizatiort Information and Communication Technologies (ICTs) Development Index (ID1) spatial ditlbrence digital divide
下载PDF
Anomaly Detection in MODIS Land Products via Time Series Analysis 被引量:1
20
作者 ZHANG Jingxiong David Roy +1 位作者 Sadashiva Devadiga ZHENG Min 《Geo-Spatial Information Science》 2007年第1期44-50,共7页
With remote sensing information products becoming increasingly varied and arguably improved, scientific applications of such products rely on their quality assessment. In an operational context such as the NASA (Natio... With remote sensing information products becoming increasingly varied and arguably improved, scientific applications of such products rely on their quality assessment. In an operational context such as the NASA (National Aeronautics and Space Administration) information production based on the MODIS (Moderate Resolution Imaging Spectroradiometer) instrument on board Earth Observing System (EOS) Terra and Aqua satellites, efficient ways of detecting product anomaly, i.e., to discriminate between product artifacts and real changes in Earth processes being monitored, are extremely important to assist and inform the user communities about potential unreliability in the products. A technique for anomaly detection, known as MAD (the median of absolute deviate from the median), in MODIS land products via time series analysis is described, which can handle intra- and in-ter-annual variation in the data by using MAD statistics of the original data and their first-order difference. This method is shown to be robust and work across major land products, including NDVI, active fire, snow cover, and surface reflectance, and its applicabil-ity to multi-disciplinary products is anticipated. 展开更多
关键词 anomaly detection MODIS land products time series
下载PDF
上一页 1 2 8 下一页 到第
使用帮助 返回顶部