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移动网络语音质差根因定位模型研究与应用
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作者 刘天雪 郝双洋 +2 位作者 杨姣 白丽丽 李娟 《计算机应用文摘》 2023年第13期70-72,共3页
围绕数字化运营建设要求,基于VoLTE端到端关联分析系统多维度对IMS域网络关键性能指标中的相关失败次数做波动分析,实现网络KPI波动告警和劣化指标异常原因定界定位,对网络异常做出智能预警,在问题暴露前优化网络,以免对业务造成影响。... 围绕数字化运营建设要求,基于VoLTE端到端关联分析系统多维度对IMS域网络关键性能指标中的相关失败次数做波动分析,实现网络KPI波动告警和劣化指标异常原因定界定位,对网络异常做出智能预警,在问题暴露前优化网络,以免对业务造成影响。通过数智化手段多维度分析定位移动网络语音质差根因,实现网络隐患故障的早预警、早发现、早处理,提升运营效率和网络质量。 展开更多
关键词 数字化运营 语音质 运营效率
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基于轨道根数差的卫星编队自主定轨研究 被引量:2
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作者 雪丹 曹喜滨 +1 位作者 吴云华 吴宝林 《系统仿真学报》 EI CAS CSCD 北大核心 2006年第10期2952-2955,共4页
设计一种应用于卫星编队的自主相对轨道确定方案。不同于目前广泛采用的Hill方程,采用轨道根数差的形式描述编队卫星间的相对运动规律,选择“无线电+激光”的组合测量方法,利用星间距离信息与方位信息作为观测量,设计扩展卡尔曼滤波器... 设计一种应用于卫星编队的自主相对轨道确定方案。不同于目前广泛采用的Hill方程,采用轨道根数差的形式描述编队卫星间的相对运动规律,选择“无线电+激光”的组合测量方法,利用星间距离信息与方位信息作为观测量,设计扩展卡尔曼滤波器实现环绕星相对轨道的自主确定。仿真结果验证了这种导航方案的有效性。 展开更多
关键词 卫星编队 轨道 自主定轨 扩展卡尔曼滤波
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巧用一元二次方程两根之差公式解题
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作者 李云柱 《中小学数学(初中学生版)》 2003年第12期13-15,共3页
关键词 一元二次方程 根差公式 解题技巧 抛物线 坐标轴 交点 中考 竞赛题 数学
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Vertical root distribution characters of Robinia pseudoacacia on the Loess Plateau in China 被引量:3
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作者 李鹏 赵忠 李占斌 《Journal of Forestry Research》 SCIE CAS CSCD 2004年第2期87-92,i001,共7页
On the Loess Plateau, water is the main limiting factors for vegetation growth. Root distribution characters have special ecological meaning as it reflected the utilizations of trees to the environments. Even-aged sta... On the Loess Plateau, water is the main limiting factors for vegetation growth. Root distribution characters have special ecological meaning as it reflected the utilizations of trees to the environments. Even-aged stands ofRobinia pseudoacacia on slope lands facing south and north were selected as sampling plots for root distribution investigation. Investigatiing results showed that indicated that on all sites, root biomass decreased with depth, and the distribution depth of fine root was deeper than that of coarser root. The results of variance analysis indicated that there were great differences in root biomass among different diameter classes, and coarser root was the main sources of variance, and the root biomass, especially fine root (?<3mm) biomass on northern exposition sites was bigger than that on southern exposition sites. Analysis of the vertical root distribution parameters, root extinction coefficient, β indicated that the value of β on northern exposition was more than 0.982, while the value of β on southern exposition was less than 0.982, which indicated that the vertical root distribution depth ofRobinia pseudoacacia on southern exposition was deeper than that on southern exposition. And the distribution depth of fine roots (Φ<1mm) was deeper than that of thicker roots(Φ<3mm), which was in favor of the uptake of water and nutrients from deeper layers, helped the trees to adapt the arid environment, and promoted the growth of the upper parts of the tree. Keywords Root diameter classes - Variance analysis - Root extinction coefficient - Vertical distribution characters - Site conditions - Loess Plateau CLC number S792.27.01 Document code A Foundation Item: This research was supported by National Natural Science Foundation of China (30371150 and 40371075).Biography: LI Peng (1974-) male, post: Ph. D. in Northwest Scientific & Technological University of Agriculture and Forestry, Yangling 712100, Shaanxi Province, P. R. China. Tel: 029-82312651.Responsible editor: Chai Ruihal 展开更多
关键词 Root diameter classes Variance analysis Root extinction coefficient Vertical distribution characters Site conditions Loess Plateau
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基于智能运营平台的核心网数字化运营实践与思考 被引量:1
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作者 高功应 马田丰 +1 位作者 李蓉 尼松涛 《邮电设计技术》 2022年第1期12-18,共7页
随着虚拟化、5G、MEC等新技术引入,核心网运营难度明显增加,需要尽快提升数字化运营能力。从构建智能化运营平台出发,探讨在一级NFVO、自动拨测系统、优化及预警系统、Vo LTE端到端优化系统等方面的重要实践,结合典型应用场景详细分析... 随着虚拟化、5G、MEC等新技术引入,核心网运营难度明显增加,需要尽快提升数字化运营能力。从构建智能化运营平台出发,探讨在一级NFVO、自动拨测系统、优化及预警系统、Vo LTE端到端优化系统等方面的重要实践,结合典型应用场景详细分析了如何实现可视、可控、可评测的数字化运营能力,并从市场、用户、一线的角度,对核心网数字化运营工作进行了展望和总结。 展开更多
关键词 核心网 智能化运营平台 因分析
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Genotypic Variation in Root Morphological Characteristics of Common Bean in Relation to Phosphorus Efficiency 被引量:10
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作者 廖红 严小龙 《Acta Botanica Sinica》 CSCD 2001年第11期1161-1166,共6页
Root morphology in plants may be related to phosphorus (P) efficiency by affecting the absorption characteristics of the root system. However, genotypic variation in root morphological characteristics of common bean (... Root morphology in plants may be related to phosphorus (P) efficiency by affecting the absorption characteristics of the root system. However, genotypic variation in root morphological characteristics of common bean ( Phaseolus vulgaris L.) as affected by P availability has not been well clarified. In the present study, systematic studies were conducted in a P-buffered sand culture system using three pairs of common bean parental materials with contrasting root traits in response to P deficiency. The results indicate that P availability significantly affects bean root morphology. Common bean tends to have smaller root system, shorter and coarser roots at low P availability. Genotypic variation in root morphology was observed among different genotypes in response to P availability. The P efficient genotypes appear to have larger, finer and longer root systems than the P inefficient genotypes, and such a variation was particularly obvious in the basal roots. From allomeric analysis, we found that morphological characteristics of the basal roots contribute more to P efficiency than those of the tap roots. Further studies with the F-9 recombinant inbred lines derived from one of the most contrasting parental pairs, DOR364 and G19833, confirmed the above findings, indicating that those morphological characteristics are inheritable hence provide potential for genetic improvement. 展开更多
关键词 common bean root morphology phosphorus efficiency genotypic variation
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近圆参考轨道卫星编队洛仑兹力控制
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作者 彭超 高扬 《力学学报》 EI CSCD 北大核心 2012年第5期851-860,共10页
基于运动电荷在磁场中切割磁力线受到洛仑兹力作用的物理规律,分析了两种带电模式对经典轨道根数长期变化的影响:(1)卫星恒定带电模式;(2)前半个轨道周期卫星带电、后半周期不带电的非恒定带电模式.恒定带电模式可以有效地改变轨道升交... 基于运动电荷在磁场中切割磁力线受到洛仑兹力作用的物理规律,分析了两种带电模式对经典轨道根数长期变化的影响:(1)卫星恒定带电模式;(2)前半个轨道周期卫星带电、后半周期不带电的非恒定带电模式.恒定带电模式可以有效地改变轨道升交点赤经、近地点幅角以及平近点角,对轨道半长轴、偏心率和倾角几乎不产生长期影响;而非恒定带电模式则可以有效地改变轨道偏心率.基于洛仑兹力作用下轨道根数长期变化规律以及轨道根数差描述的带电副星相对于不带电主星的运动,提出了利用洛仑兹力以及两种带电模式实现地球低轨近圆参考轨道卫星编队的控制策略,包括编队绕飞椭圆大小重构与编队中心漂移控制,解析求解了副星所需的带电量,并利用数值仿真验证了洛仑兹力控制的可行性.需要指出的是,洛仑兹力轨道控制无需消耗推进工质. 展开更多
关键词 带电卫星 地球磁场 洛仑兹力 卫星编队 轨道 编队重构
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Gene Chip Analysis of Expression Pattern of Type I Inner Root Sheath (IRS) Keratin in AoHan Wool Sheep 被引量:3
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作者 余娟娟 刘积凤 +3 位作者 赵金山 程明 刘开东 柳楠 《Agricultural Science & Technology》 CAS 2012年第6期1171-1174,共4页
[Objective] The paper was to study the expression pattern of specific genes during wool anagen and telogen stages and its significance to AoHan wool sheep breeding. [Method] Gene chip technology was used to detect the... [Objective] The paper was to study the expression pattern of specific genes during wool anagen and telogen stages and its significance to AoHan wool sheep breeding. [Method] Gene chip technology was used to detect the expression of epithelial genes in neck and groin during anagen and telogen stages in AoHan wool sheep. [Result] The expression of type Ⅰ IRS keratin genes KRT25, KRT26, KRT27 and KRT28 in neck and groin of wool sheep were statistically analyzed, and the result showed that the expression in neck during anagen stage was significantly higher than that in groin (The multiple was more than two times, P0.01). The expression changes of the genes during anagen and telogen stages were compared, and the results showed that the expression of all Type I IRS Keratin genes performed in groin showed significant decrease from anagen stage to telogen stage (P 0.05), the expression changes of other genes were two times higher, except KRT25 (LOC443079). [Conclusion] The result indicated that the expression of type Ⅰ IRS Keratin genes is closely related with the control of wool density in specific part and the whole wool development cycle. 展开更多
关键词 Atractylodes lance(Thunb.)DC. Orthogonal Design HORMONE Substrate
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Aesthetic comparison between Chinese memorial poetry and western elegy
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作者 张丽娟 王旻 《Sino-US English Teaching》 2007年第8期76-81,共6页
Owing to the cultural, philosophical and religious differences, Chinese memorial poetry and western elegy show different attitudes towards death and have different ways to express it. Therefore, they have different ae... Owing to the cultural, philosophical and religious differences, Chinese memorial poetry and western elegy show different attitudes towards death and have different ways to express it. Therefore, they have different aesthetic preference to death. This paper focuses on the basic characteristics of Chinese memorial poetry and western elegy. It analyzes the causes of these differences from the aspect of the content and style, ways of expression and cultural psychology. 展开更多
关键词 memorial poetry ELEGY DIFFERENCE cultural root
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应用新型回转盖板骨架降低梳棉棉结
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作者 户芝 《纺织器材》 2022年第2期15-17,共3页
为了提高回转盖板—锡林隔距稳定性,介绍回转盖板骨架的发展以及宽幅梳棉机回转盖板骨架的要求,通过对比国内外梳棉机铝合金回转盖板骨架的结构,开发出具有预设弯曲张力的可调节回转盖板骨架和铝合金回转盖板踵趾块。试验结果表明:新型... 为了提高回转盖板—锡林隔距稳定性,介绍回转盖板骨架的发展以及宽幅梳棉机回转盖板骨架的要求,通过对比国内外梳棉机铝合金回转盖板骨架的结构,开发出具有预设弯曲张力的可调节回转盖板骨架和铝合金回转盖板踵趾块。试验结果表明:新型专利铝合金盖板骨架通过在腔体内增加横筋和碳纤维调节杆,增加回转盖板骨架抗剪力和运行过程的抗挠强度,解决宽幅梳棉机铝合金回转盖板骨架变形大、根差大、隔距难调整、易造成针布接针等问题;采用特殊耐磨材料经粉末冶金制作铝合金回转盖板踵趾块,可改善普通踵趾面耐磨性差、使用寿命短的问题。 展开更多
关键词 梳棉机 回转盖板 宽幅 回转盖板骨架 根差 隔距 碳纤维 踵趾块 踵趾
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Differential response of root morphology to potassium deficient stress among rice genotypes varying in potassium efficiency 被引量:36
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作者 Yan-bo JIA Xiao-e YANG +1 位作者 Ying FENG Ghulam JILANI 《Journal of Zhejiang University-Science B(Biomedicine & Biotechnology)》 SCIE CAS CSCD 2008年第5期427-434,共8页
Disparity in the root morphology of six rice(Oryza sativa L.) genotypes varying in potassium(K) efficiency was studied with three K levels:5 mg/L(low),10 mg/L(moderate) and 40 mg/L(adequate) in hydroponic culture. Mor... Disparity in the root morphology of six rice(Oryza sativa L.) genotypes varying in potassium(K) efficiency was studied with three K levels:5 mg/L(low),10 mg/L(moderate) and 40 mg/L(adequate) in hydroponic culture. Morphological parameters included root length,surface area,volume and count of lateral roots,as well as fine(diameter<0.2 mm) and thick(diameter>0.2 mm) roots. The results indicate that the root growth of all genotypes was reduced under low K,but moderate K deficiency increased the root length of the efficient genotypes. At deficient and moderate K levels,all the efficient rice genotypes developed more fine roots(diameter<0.2 mm) than the inefficient ones. Both fine root count and root surface area were found to be the best parameters to portray K stress in rice. In accordance with the root morphology,higher K concentrations were noted in shoots of the efficient genotypes when grown at moderate and deficient K levels,indicating that root morphology parameters are involved in root uptake for K and in the translocation of K up to shoots. K deficiency affected not only the root morphology,but also the root ultra-structure. The roots of high-efficient genotypes had stronger tolerance to K deficient stress for root membrane damage,and could maintain the developed root architecture to adapt to the low K growth medium. 展开更多
关键词 Genotypic difference Potassium (K) efficiency Root surface area Fine root development Root cell utra-structure
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A Model for Estimating Total Forest Coverage with Ground-Based Digital Photography 被引量:5
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作者 GU Zhu-Jun ZENG Zhi-Yuan +5 位作者 SHI Xue-Zheng LI Lin D. C. WEINDORF ZHA Yong YU Dong-Sheng LIU YongoMei 《Pedosphere》 SCIE CAS CSCD 2010年第3期318-325,共8页
Vegetation fractional coverage (VFC) is one of the key indicators of vegetation distribution. In the work a measurement-based model was developed to derive total forest VFC (TG) as well as the VFC of trees (T) and shr... Vegetation fractional coverage (VFC) is one of the key indicators of vegetation distribution. In the work a measurement-based model was developed to derive total forest VFC (TG) as well as the VFC of trees (T) and shrub-grasses (G) separately in a subtropical forest area in Nanjing, China. Both upward and downward photographs were taken with a digital camera in 72 quadrats (10 m × 10 m each). Fifteen models were established and validated. Models jointly using both T and G performed better than those using the T and G separately. The best model, TG = T + G- 1.134 × T × G- 0.025 (R2 = 0.9115, P < 0.01, root mean squared error = 0.0789), is recommended for application. This model provides a good way to obtain total forest VFC values through taking tree and shrub-grass photos on ground below tree canopy rather than above tree canopy. 展开更多
关键词 digital camera 2-layer photography shrub-grasses trees
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Validation and intercomparison of HY-2A/MetOp-A/Oceansat-2 scatterometer wind products 被引量:5
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作者 吴庆 陈戈 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2015年第5期1181-1190,共10页
Sea surface winds are of great significance in scientific research. In the last few years,three series of scatterometers were launched to measure these winds,including the Advanced Scatterometer(ASCAT) aboard Meteorol... Sea surface winds are of great significance in scientific research. In the last few years,three series of scatterometers were launched to measure these winds,including the Advanced Scatterometer(ASCAT) aboard Meteorological Operational Satellite A(Met Op-A) and Met Op-B,Oceansat-2 Scatterometer(OSCAT),and HY-2A Scatterometer(HY-2A SCAT). Based on buoy wind data,validation and intercomparison of these scatterometers were performed. Scatterometer-derived wind and buoy wind data were collected only if the spatial difference was less than 0.1 degree and temporal difference less than 5 min. After discarding wind direction data outside five times the standard deviation,ASCAT wind products showed high accuracy in both wind speed and direction,with root-mean-square error(RMSE) 0.86 m/s and 17.97 degrees,respectively. HY-2A SCAT nearly meets the mission requirement,with RMSE for wind speed 1.23 m/s and 22.85 degrees for wind direction. OSCAT had poor performance when compared with the others. RMSE for wind speed was 1.54 m/s and 39.86 degrees for wind direction,which greatly exceeds the mission requirement of 20 degrees. In addition,the RMSE for wind direction shows a high-low pattern on buoy wind speed. However,a wind speed range from 14 to 15 m/s was found to be abnormal,and the reason remains unclear. There was no systematic dependency of both wind speed and direction residuals on buoy wind speed and cross-track location of the wind vector cells across the entire range. No seasonal variation was found for any scatterometer. 展开更多
关键词 SCATTEROMETER WIND VALIDATION intercomparison
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Estimating van Genuchten Model Parameters of Undisturbed Soils Using an Integral Method 被引量:16
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作者 HAN Xiang-Wei SHAO Ming-An R. HORTON 《Pedosphere》 SCIE CAS CSCD 2010年第1期55-62,共8页
The van Genuchten model is the most widely used soil water retention curve (SWRC) model. Two undisturbed soils (clay and loam) were used to evaluate the accuracy of the integral method to estimate van Genuchten mo... The van Genuchten model is the most widely used soil water retention curve (SWRC) model. Two undisturbed soils (clay and loam) were used to evaluate the accuracy of the integral method to estimate van Genuchten model parameters and to determine SWRCs of undisturbed soils. SWRCs calculated by the integral method were compared with those measured by a high speed centrifuge technique. The accuracy of the calculated results was evaluated graphically, as well as by root mean square error (RMSE), normalized root mean square error (NRMSE) and Willmott's index of agreement (1). The results obtained from the integral method were quite similar to those by the centrifuge technique. The RMSEs (4.61 ×10^-5 for Eum-Orthic Anthrosol and 2.74 × 10^-4 for Los-Orthic Entisol) and NRMSEs (1.56 × 10^-4 for Eum- Orthic Anthrosol and 1.45 ×10^-3 for Los-Orthic Entisol) were relatively small. The 1 values were 0.973 and 0.943 for Eum-Orthic Anthrosol and Los-Orthic Entisol, respectively, indicating a good agreement between the integral method values and the centrifuge values. Therefore, the integral method could be used to estimate SWRCs of undisturbed clay and loam soils. 展开更多
关键词 horizontal infiltration normalized root mean square error (NRMSE) root mean square error (RMSE) water retention. Willmott's index
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Comparison of six statistical approaches in the selection of appropriate fish growth models 被引量:6
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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
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Comparative Analysis of Four Stem Taper Models for Quercus glauca in Mount Halla,Jeju Island,South Korea 被引量:1
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作者 LUMBRES Roscinto Ian Canicosa LEE Young Jin +6 位作者 CHOI Hyung Soon KIM Sung Yong JANG Mi Na ABINO Azyleah Caizares SEO Yeon Ok KIM Chan Soo PARK Jung Hwan 《Journal of Mountain Science》 SCIE CSCD 2014年第2期442-448,共7页
This study was conducted to fit the diameter-height data of Quercusglaucain Jeju Island, South Korea to the four commonly used stem taper equations andto evaluate the performance of the four stem taper models using fo... This study was conducted to fit the diameter-height data of Quercusglaucain Jeju Island, South Korea to the four commonly used stem taper equations andto evaluate the performance of the four stem taper models using four statistical criteria: Fit index (FI), root mean square error (RMSE), bias (),and absolute mean difference (AMD). Results showed that the Kozak02stem taper equation provided the best FI(0.9847), RMSE(1.5745),(-0.0030 cm) and AMD (1.0990 cm) whileMax and Burkhart model had the poorest performance among the four stem taper models based on the four evaluation statistics (FI : 0.9793,RMSE : 1.8272, : 0.3040 cm and AMD : 1.3060 cm). These stem taper equations can serve as a useful tool for forest managers in estimating the diameter outside bark at any given height, merchantable stem volumes and total stem volumesof the standing trees of Quercusglaucain theGotjawal forests located in Mount Halla, Jeju Island, South Korea. 展开更多
关键词 MountHalla Merchantable stem volume Diameter outside bark Kozak model Model evaluation
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Slope displacement prediction based on morphological filtering 被引量:4
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作者 李启月 许杰 +1 位作者 王卫华 范作鹏 《Journal of Central South University》 SCIE EI CAS 2013年第6期1724-1730,共7页
Combining mathematical morphology (MM),nonparametric and nonlinear model,a novel approach for predicting slope displacement was developed to improve the prediction accuracy.A parallel-composed morphological filter wit... Combining mathematical morphology (MM),nonparametric and nonlinear model,a novel approach for predicting slope displacement was developed to improve the prediction accuracy.A parallel-composed morphological filter with multiple structure elements was designed to process measured displacement time series with adaptive multi-scale decoupling.Whereafter,functional-coefficient auto regressive (FAR) models were established for the random subsequences.Meanwhile,the trend subsequence was processed by least squares support vector machine (LSSVM) algorithm.Finally,extrapolation results obtained were superposed to get the ultimate prediction result.Case study and comparative analysis demonstrate that the presented method can optimize training samples and show a good nonlinear predicting performance with low risk of choosing wrong algorithms.Mean absolute percentage error (MAPE) and root mean square error (RMSE) of the MM-FAR&LSSVM predicting results are as low as 1.670% and 0.172 mm,respectively,which means that the prediction accuracy are improved significantly. 展开更多
关键词 slope displacement prediction parallel-composed morphological filter functional-coefficient auto regressive predictionaccuracy
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Satellite derived upper ocean thermal structure and its application to tropical cyclone intensity forecasting in the Indian Ocean 被引量:1
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作者 孙春健 王喜冬 +6 位作者 崔晓健 张晓爽 张连新 邵彩霞 吴新荣 付红丽 李威 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2015年第5期1219-1232,共14页
Upper ocean heat content is a factor critical to the intensity change of tropical cyclones(TCs). Because of the inhomogeneity of in situ observations in the North Indian Ocean,gridded temperature/salinity(T/S) profile... Upper ocean heat content is a factor critical to the intensity change of tropical cyclones(TCs). Because of the inhomogeneity of in situ observations in the North Indian Ocean,gridded temperature/salinity(T/S) profiles were derived from satellite data for 1993–2012 using a linear regression method. The satellite derived T/S dataset covered the region of 10°S–32°N,25°–100°E with daily temporal resolution,0.25°×0.25° spatial resolution,and 26 vertical layers from the sea surface to a depth of 1 000 m at standard layers. Independent Global Temperature Salinity Profile Project data were used to validate the satellite derived T/S fields. The analysis confirmed that the satellite derived temperature field represented the characteristics and vertical structure of the temperature field well. The results demonstrated that the vertically averaged root mean square error of the temperature was 0.83 in the upper 1 000 m and the corresponding correlation coefficient was 0.87,which accounted for 76% of the observed variance. After verification of the satellite derived T/S dataset,the TC heat potential(TCHP) was verified. The results show that the satellite derived values were coherent with observed TCHP data with a correlation coefficient of 0.86 and statistical significance at the 99% confidence level. The intensity change of TC Gonu during a period of rapid intensification was studied using satellite derived TCHP data. A delayed effect of the TCHP was found in relation to the intensity change of Gonu,suggesting a lag feature in the response of the inner core of the TC to the ocean. 展开更多
关键词 tropical cyclone intensification tropical cyclone heat potential sea surface temperature seasurface height
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3-D reconstruction of coastal bathymetry from AIRSAR/POLSAR data 被引量:1
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作者 Maged MARGHANY Mazlan HASHIM Arthur P. CRACKNELL 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2009年第1期117-123,共7页
This paper introduces a new method for reconstructing three-dimensional (3D) coastal bathymetry changes from Airborne AIRSAR/POLSAR synthetic aperture data. The new method is based on integration between fuzzy B-spl... This paper introduces a new method for reconstructing three-dimensional (3D) coastal bathymetry changes from Airborne AIRSAR/POLSAR synthetic aperture data. The new method is based on integration between fuzzy B-spline and Volterra algorithm. Volterra algorithm is used to simulate the ocean surface current from AIRSAR/POLSAR data. Then, the ocean surface current information used as input for continuity equation to estimate the water depths from AIRSAR/POLSAR data. This study shows that 3D ocean bathymetry can be reconstructed from AIRSAR/POLSAR data with root mean square error of ±0.03 m. 展开更多
关键词 AIRSAR/POLSAR data Volterra algorithm Fuzzy B-spline 3D bathymetry
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CARRIER FREQUENCY OFFSET ESTIMATION FOR INTERLEAVED OFDMA UPLINK BASED ON SUBSPACE PROCESSING 被引量:1
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作者 Fan Da Cao Zhigang 《Journal of Electronics(China)》 2007年第4期433-438,共6页
This paper investigates Carrier Frequency Offset (CFO) estimation in the uplink of the Orthogonal Frequency-Division Multiple Access (OFDMA) systems with the interleaved subcarrier assignment. CFOs between the transmi... This paper investigates Carrier Frequency Offset (CFO) estimation in the uplink of the Orthogonal Frequency-Division Multiple Access (OFDMA) systems with the interleaved subcarrier assignment. CFOs between the transmitters and the uplink receiver will destroy orthogonality among different subcarriers, hence resulting in inter-carrier interference and multiuser interference. A two-stage frequency offset estimation algorithm based on subspace processing is proposed. The main advantage of the proposed method is that it can obtain the CFOs of all users simultaneously using only one OFDMA block. Compared with the previously known methods, it not only has a relatively low implementation complexity but is also suitable for random subchannel assignment. 展开更多
关键词 Orthogonal Frequency-Division Multiple Access (OFDMA) Carrier Frequency Offset (CFO) Subspace processing Normalized Root Mean Square Error (NRMSE)
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