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Determined Reverberant Blind Source Separation of Audio Mixing Signals
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作者 Senquan Yang Fan Ding +2 位作者 Jianjun Liu Pu Li Songxi Hu 《Intelligent Automation & Soft Computing》 SCIE 2023年第6期3309-3323,共15页
Audio signal separation is an open and challenging issue in the classical“Cocktail Party Problem”.Especially in a reverberation environment,the separation of mixed signals is more difficult separated due to the infl... Audio signal separation is an open and challenging issue in the classical“Cocktail Party Problem”.Especially in a reverberation environment,the separation of mixed signals is more difficult separated due to the influence of reverberation and echo.To solve the problem,we propose a determined reverberant blind source separation algorithm.The main innovation of the algorithm focuses on the estimation of the mixing matrix.A new cost function is built to obtain the accurate demixing matrix,which shows the gap between the prediction and the actual data.Then,the update rule of the demixing matrix is derived using Newton gradient descent method.The identity matrix is employed as the initial demixing matrix for avoiding local optima problem.Through the real-time iterative update of the demixing matrix,frequency-domain sources are obtained.Then,time-domain sources can be obtained using an inverse short-time Fourier transform.Experi-mental results based on a series of source separation of speech and music mixing signals demonstrate that the proposed algorithm achieves better separation performance than the state-of-the-art methods.In particular,it has much better superiority in the highly reverberant environment. 展开更多
关键词 determined mixtures reverberant environment audio signal separation cocktail party problem
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Earthquake focal mechanisms and stress field in Sichuan-Yunnan area determined using P wave polarity and short period P and S waveform data 被引量:1
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作者 陈天长 郑斯华 ZHENG Si-hua 《Acta Seismologica Sinica(English Edition)》 CSCD 2001年第4期466-470,共5页
关键词 Sichuan-Yunnan area FOCAL mechanism stress field 分类号:P315.3+3 文献标识码:A 文章编号:1000-9116(2001)04-0466-05 Based on waveform data several methods to determine FOCAL mechanisms of SMALL EARTHQUAKES were developed since 1980. Kisslinger (1980) and Julian Foulger (1996) proposed an approach to determine solution by using amplitude ratio of P and S wave. Schwartz (1995) devised a method to determine solutions by the use of polarity DATA and amplitudes of seismogram envelopes. Amplitudes of short period seismic waves propagating in an inhomogene-ous medium ARE sensitive to the variation in velocity and Q structure. Nakamura et al (1999) took medium inhomo-geneity into account in determining FOCAL mechanisms of SMALL EARTHQUAKES using waveform data. If the locations of SMALL EARTHQUAKES ARE concentrated in a SMALL region we can assume that the raypaths from the events to a given station ARE almost the same. So P and S wave attenuations ARE independent of event locations. In this case it is con-venient to determine FOCAL mechanisms of these events by using short period P and S wave dataj. FOCAL mechanism solutions of SMALL EARTHQUAKES in 5 regions i.e. Rongchang Mabian-Muchuan Ya'an Baoxing and Mianzhu which ARE covered by the Chengdu Telemetered Network ARE obtained by analyzing the P polarity and short body wave amplitude DATA recorded in the network since 1992. According to the method proposed by Gephart and Forsyth (1984) based on well determined FOCAL mechanism solutions in 15 sub-zones of Sichuan and Yunnan area three principal stress tensors s1 s2 and s3 instead of averages of P B and T axis of the solutions ARE determined to represent the regional stress field distribution.……
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A New Parameter of Cleanability to Determine the Clean Potential of Coal Resources 被引量:2
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作者 TANG Yuegang YANG Shuting WANG Xiaoshuai 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2017年第6期2338-2339,共2页
Objective This work is based on analysis on large numbers of coal data such as the latest national coal potential evaluation data and previous data published by REN Deyi,TANG Xiuyi and LU Xukun,and the evaluation meth... Objective This work is based on analysis on large numbers of coal data such as the latest national coal potential evaluation data and previous data published by REN Deyi,TANG Xiuyi and LU Xukun,and the evaluation methods of clean potential of coal resources proposed by predecessors.It is found that previous method rank coal is only in accordance with raw coal or washed coal,which fail 展开更多
关键词 In A New Parameter of Cleanability to determine the Clean Potential of Coal Resources
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Climate Warming Mitigation from Nationally Determined Contributions 被引量:1
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作者 Bo FU Jingyi LI +7 位作者 Thomas GASSER Philippe CIAIS Shilong PIAO Shu TAO Guofeng SHEN Yuqin LAI Luchao HAN Bengang LI 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2022年第8期1217-1228,共12页
Individual countries are requested to submit nationally determined contributions(NDCs)to alleviate global warming in the Paris Agreement.However,the global climate effects and regional contributions are not explicitly... Individual countries are requested to submit nationally determined contributions(NDCs)to alleviate global warming in the Paris Agreement.However,the global climate effects and regional contributions are not explicitly considered in the countries’decision-making process.In this study,we evaluate the global temperature slowdown of the NDC scenario(ΔT=0.6°C)and attribute the global temperature slowdown to certain regions of the world with a compact earth system model.Considering reductions in CO_(2),CH_(4),N_(2)O,BC,and SO_(2),the R5OECD(the Organization for Economic Co-operation and Development in 1990)and R5ASIA(Asian countries)are the top two contributors to global warming mitigation,accounting for 39.3%and 36.8%,respectively.R5LAM(Latin America and the Caribbean)and R5MAF(the Middle East and Africa)followed behind,with contributions of 11.5%and 8.9%,respectively.The remaining 3.5%is attributed to R5REF(the Reforming Economies).Carbon Dioxide emission reduction is the decisive factor of regional contributions,but not the only one.Other greenhouse gases are also important,especially for R5MAF.The contribution of short-lived aerosols is small but significant,notably SO_(2)reduction in R5ASIA.We argue that additional species beyond CO_(2)need to be considered,including short-lived pollutants,when planning a route to mitigate climate change.It needs to be emphasized that there is still a gap to achieve the Paris Agreement 2-degree target with current NDC efforts,let alone the ambitious 1.5-degree target.All countries need to pursue stricter reduction policies for a more sustainable world. 展开更多
关键词 climate mitigation nationally determined contributions ATTRIBUTION regional contribution integrated assessment models
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KT Boundary Chromites Determined to be Terrestrial:Cr Isotopic Evidence for Excavation and Ejection of Mafic/Ultramafic Rocks by the KT Boundary Impact 被引量:1
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作者 Peter OLDS Mathew E.SANBORN +1 位作者 Tim TEAGUE YIN Qingzhu 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2017年第S1期26-27,共2页
Evidence for a mantle and/or basaltic component in KT boundary distal ejecta is apparently inconsistent with ejection from Chicxulub Crater since it is located on^35km thick continental crust(De Paolo et al.,1983;Mont... Evidence for a mantle and/or basaltic component in KT boundary distal ejecta is apparently inconsistent with ejection from Chicxulub Crater since it is located on^35km thick continental crust(De Paolo et al.,1983;Montanari et al.,1983;Hildebrand and Boynton,1988,1990).Evidence for mafic/ultramafic target rocks was reinforced by discovery of chromites,some with shock planar deformation features(PDF),in impact layer samples from sites in southern Colorado and eastern Wyoming(Bohor et al.,1990).However,until now it was unclear whether the chromites originated with an impactor or with terrestrial target rocks.To this end,high-precision 54Cr/52Cr isotope ratios were measured on KT boundary chromites along with known terrestrial chromites.We find a terrestrial 54Cr/52Cr ratio in KT boundary chromites from impact layer samples collected at the above sites over the last several years(Fig.1).Ejected terrestrial chromites suggest the impact sampled terrestrial mafic and/or ultramafic target rocks not known to exist in the Chicxulub target area. 展开更多
关键词 KT Boundary Chromites determined to be Terrestrial Cr Isotopic Evidence for Excavation and Ejection of Mafic/Ultramafic Rocks by the KT Boundary Impact
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determine用法种种
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作者 赵常玲 《英语辅导(高中年级)》 2002年第1期7-7,共1页
determine v.“决心、决定”。
关键词 determine 用法 高中 英语
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再论DETERMINER
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作者 国文 《昌潍师专学报》 1998年第3期56-57,共2页
Determiner 是国外语言学家提出的话法术语,在各种语法著作中当做词类介绍,国内语言学界将其译为"限定词"。作者在分析了其来源、构成、分类及作用等后,提出 Determiner 不应被视作"词",而应看作是词组成分,可译为&... Determiner 是国外语言学家提出的话法术语,在各种语法著作中当做词类介绍,国内语言学界将其译为"限定词"。作者在分析了其来源、构成、分类及作用等后,提出 Determiner 不应被视作"词",而应看作是词组成分,可译为"限定语"。 展开更多
关键词 determineR 限定词 词组成分 限定语
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An Improved Experiment to Determine the‘Past of a Particle’in the Nested Mach-Zehnder Interferometer
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作者 A.Ben-Israel L.Knips +4 位作者 J.Dziewior J.Meinecke A.Danan H.Weinfurter L.Vaidman 《Chinese Physics Letters》 SCIE CAS CSCD 2017年第2期4-6,共3页
We argue that the modification proposed by Li et al. [Chin. Phys. Lett. 32(2015) 050303] to the experiment of Danan et al. [Phys. Rev. Lett. 111(2013) 240402] does not test the past of the photon as characterized by l... We argue that the modification proposed by Li et al. [Chin. Phys. Lett. 32(2015) 050303] to the experiment of Danan et al. [Phys. Rev. Lett. 111(2013) 240402] does not test the past of the photon as characterized by local weak traces. Instead of answering the questions:(ⅰ) were the photons in A?(ⅱ) were the photons in B? and(ⅲ)were the photons in C? the proposed experiment measures a degenerate operator answering the questions:(ⅰ)were the photons in A? and(ⅱ) were the photons in B and C together? A negative answer to the last question does not tell us if photons were present in B or C. On the other hand, a simple variation of the proposal by Li et al. does provide conceptually better evidence for the past of the pre-and post-selected photon, but this evidence will be in agreement with the results of Danan et al. 展开更多
关键词 LI In in the Nested Mach-Zehnder Interferometer An Improved Experiment to determine the
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Carrier Dynamics Determined by Carrier-Phonon Coupling in InGaN/GaN Multiple Quantum Well Blue Light Emitting Diodes
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作者 曹盛 吴小明 +1 位作者 刘军林 江风益 《Chinese Physics Letters》 SCIE CAS CSCD 2019年第2期92-95,共4页
Phonon sidebands in the electrolumiescence(EL) spectra of InGaN/GaN multiple quantum well blue light emitting diodes are investigated. S-shaped injection current dependence of the energy spacing(ES) between the zero-p... Phonon sidebands in the electrolumiescence(EL) spectra of InGaN/GaN multiple quantum well blue light emitting diodes are investigated. S-shaped injection current dependence of the energy spacing(ES) between the zero-phonon and first-order phonon-assisted luminescence lines is observed in a temperature range of 100–150 K.The S-shape is suppressed with increasing temperature from 100 to 150 K, and vanishes at temperature above200 K. The S-shaped injection dependence of ES at low temperatures could be explained by the three stages of carrier dynamics related to localization states:(i) carrier relaxation from shallow into deep localization states,(ii) band filling of shallow and deep localization states, and(iii) carrier overflow from deep to shallow localization states and to higher energy states. The three stages show strong temperature dependence. It is proposed that the fast change of the carrier lifetime with temperature is responsible for the suppression of S-shaped feature.The proposed mechanisms reveal carrier recombination dynamics in the EL of InGaN/GaN MQWs at various injection current densities and temperatures. 展开更多
关键词 CARRIER Dynamics determined Carrier-Phonon Coupling INGAN/GAN Multiple Quantum Well BLUE Light EMITTING DIODES
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Comparing and evaluating the nationally determined contributions of the top six emitters under the Paris Agreement goals
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作者 Xunzhang Pan Jie Tao Hailin Wang 《Chinese Journal of Population,Resources and Environment》 2018年第3期211-219,共9页
Comparing and evaluating the Nationally Determined Contribution(NDC) is an important element in global stocktake in the post-Paris climate negotiations, aimed at closing the emissions gap with the Paris Agreement goal... Comparing and evaluating the Nationally Determined Contribution(NDC) is an important element in global stocktake in the post-Paris climate negotiations, aimed at closing the emissions gap with the Paris Agreement goals. To date, however, there has still been no explicit guideline or method. By applying emissions allowance allocated by 16 schemes as benchmarks, this paper tries to compare and evaluate the NDCs of the top six emitters, which jointly account for about 70% of the world's CO_2 emissions. Results show that the four developed countries' NDCs lack ambition with respect to most allocations under 2℃ and all under 1.5℃, indicating they need to substantially ratchet up their NDCs and lead elevating mitigation. Evaluating cumulative emissions is more likely to clarify the ambition and fairness of China's NDC. If considering cumulative emissions, China's NDC is aligned with the median of cumulative allowances under 2℃ and within the 1.5℃ range. The Paris Agreement invited the Parties to communicate the mid-century low emissions strategies. This paper also tries to explore the mid-century mitigation in the perspective of allocations, which might provide decision-makers with some useful information when envisaging the post-NDC mitigation. 展开更多
关键词 PARIS AGREEMENT nationally determined contribution top SIX EMITTERS emissions ALLOWANCE ALLOCATIONS midcentury mitigation
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A prospective study to determine the frequency of alloimmunization of red blood cell transfusion
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《中国输血杂志》 CAS CSCD 2001年第S1期376-,共1页
关键词 CELL A prospective study to determine the frequency of alloimmunization of red blood cell transfusion
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Biostratigraphy and Paleoenvironmentin ChejuSedimentary Basin,Determined by Materials from Exploration Wells Geobuk-1 and Okdom-1
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《Journal of Earth Science》 SCIE CAS CSCD 2000年第2期7-7,共1页
关键词 Biostratigraphy and Paleoenvironmentin ChejuSedimentary Basin determined by Materials from Exploration Wells Geobuk-1 and Okdom-1
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LENGTH OF WEST-TO-EAST GAS PIPELINE DETERMINED AS ABOUT 400 KILOMETERS
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《China Oil & Gas》 CAS 2000年第4期35-35,共1页
关键词 EAST LENGTH OF WEST-TO-EAST GAS PIPELINE determineD AS ABOUT 400 KILOMETERS GAS
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DETERMINE积分对右室流出道起源的室性早搏与致心律失常性右室心肌病的鉴别诊断价值
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作者 王俊 徐宗政 +2 位作者 李庆祝 汪祥海 王德国 《实用心电学杂志》 2022年第5期336-340,共5页
目的探讨DETERMINE积分对右室流出道起源的室性早搏(right ventricular outflow tract premature ventricular contraction,RVOT-PVC)与致心律失常性右室心肌病(arrhythmogenic right ventricular cardiomyopathy,ARVC)的鉴别价值。方... 目的探讨DETERMINE积分对右室流出道起源的室性早搏(right ventricular outflow tract premature ventricular contraction,RVOT-PVC)与致心律失常性右室心肌病(arrhythmogenic right ventricular cardiomyopathy,ARVC)的鉴别价值。方法回顾性分析25例ARVC和59例RVOT-PVC患者,对窦性心律心电图参数及特征进行比较。基于病理性Q波、碎裂QRS波及T波倒置的导联数计算DETERMINE积分。结果窦性心律下ARVC组epsilon波(12.00%vs.0,P<0.01)、V_(1)—V_(3)导联T波倒置(68.00%vs.37.29%,P=0.010)及左束支阻滞型室速(52.00%vs.16.95%,P=0.001)的发生率更高。单一心电图特征对ARVC的鉴别诊断效能较差(敏感性<70.0%)。ARVC组DETERMINE积分显著高于RVOT-PVC组[(5.80±2.56)分vs.(0.58±1.22)分,P<0.01]。以DETERMINE积分>3分为切点值,鉴别ARVC与RVOT-PVC的敏感性和特异性分别为92.0%和91.5%,阳性预测值和阴性预测值分别为82.8%和98.2%。结论简易DETERMINE积分可用于鉴别诊断ARVC与RVOT-PVC,具有一定的临床应用价值。 展开更多
关键词 determine积分 致心律失常性右室心肌病 心电图 右室流出道起源的室性早搏
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Japanese-Chinese Machine Translation of Japanese Determiners Based on Templates
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作者 Ling Wang Zhongjian Wang 《Modern Electronic Technology》 2022年第1期43-48,共6页
The machine translation of Japanese sentences with determiners,like“shi­ka...nai”,“tyoutto...dakedeha”,“tada...dake”and so on,are more special and regular on sentences structure.The research collects and cl... The machine translation of Japanese sentences with determiners,like“shi­ka...nai”,“tyoutto...dakedeha”,“tada...dake”and so on,are more special and regular on sentences structure.The research collects and classifies the Japanese sentences which contain the determiners.The classification is carried out by according to the characteristics of Japanese sentences and translation habit of Chinese sentences.Through further abstraction and sim­plification,translation templates are extracted by gathering grammar rules information,studying syntax and analysis the collocation mode of sentenc­es.Those determiners express confirmed meaning,and the corresponding translation Chinese sentences have the same characteristic.By analyzing the sentence characteristics with determiners and formalizing the sentences struc­ture,the translation templates are abstracted.By investigating the structure characteristic of original sentences with translation templates,the similarity algorithm was defined.The threshold value of the similarity calculation was obtained by preliminary experiments,and the experiments of Japanese-Chi­nese translation are carried out by a small corpus.The experimental results for several kinds of Japanese sentences with determiners show the translation accuracy rate is 68.6%,template coverage rate reach 83.3%.At last,through the analysis for the translation errors,following conclusion is drawn:the results of morphological analysis are erroneous,because the error of word segmentation the part of speech tagging also are erroneous,result in the grammar structure cannot match with templates;the original sentences are long and especially complex sentences;the templates are too complicated;the similarity calculation method needs to discuss further,and so on. 展开更多
关键词 Japanese determiners Similarity calculation Machine translation Translation templates
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How the Soul Boy of The 10th Bainqen Is Determined
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作者 AINAM 《China's Tibet》 1996年第1期6-9,共4页
HowtheSoulBoyofThe10thBainqenIsDetermined¥//Aninsidestoryoflocatinganddeterminingthereincarnatedsoulboyofthe... HowtheSoulBoyofThe10thBainqenIsDetermined¥//Aninsidestoryoflocatinganddeterminingthereincarnatedsoulboyofthe10thBainqen.AINAM... 展开更多
关键词 How the Soul Boy of The 10th Bainqen Is determined
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What determines irrigation efficiency when farmers face extreme weather events? A field survey of the major wheat producing regions in China 被引量:4
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作者 SONG Chun-xiao Les Oxley MA Heng-yun 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2018年第8期1888-1899,共12页
Water availability is a major constraint on grain production in China, therefore, improving irrigation efficiency is particularly important when agriculture faces extreme weather events. This paper first calculates ir... Water availability is a major constraint on grain production in China, therefore, improving irrigation efficiency is particularly important when agriculture faces extreme weather events. This paper first calculates irrigation efficiency with a translog stochastic frontier production function and then investigates what happens when extreme weather events occur via a Tobit model. The estimated results reveal several important features of irrigation practices: i) irrigation efficiency is lower when extreme weather events occur; ii) large variations in irrigation efficiency occur across irrigation facilities; iii) the farm plots exhibit an extreme distribution across efficiency levels; and iv) water-saving techniques, technology adoption, and the maintenance of farmers' economic resilience are major determinants of irrigation efficiency. Based on these results we propose the following recommendations: i) farmers should balance crop yield and water use; undertake relevant training programs and adopt water-saving techniques; ii) local governments and researchers should help farmers to find the optimal level of irrigation water use based on their own circumstances and provide better water-saving techniques and training programs rather than simply encouraging farmers to invest in irrigation facilities in the most extreme weather years; and iii) the income level of farm households should be increased so as to improve their resilience to natural disasters. 展开更多
关键词 irrigation efficiency determinants irrigation facilities water-saving techniques extreme weather events
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Numerical Experiment of Combined Infrared and Ultraviolet Radiation Remote Sensing to Determine the Profile and Total Content of Atmospheric Ozone 被引量:1
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作者 程明虎 石广玉 周秀骥 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 1990年第3期305-319,共15页
A new remote sensing method is described to determine the vertical distribution and total content of atmospheric ozone. The method combines surface infrared, satellite infrared and ultraviolet channels. The width of t... A new remote sensing method is described to determine the vertical distribution and total content of atmospheric ozone. The method combines surface infrared, satellite infrared and ultraviolet channels. The width of the infrared channels is 0.01 cm-1, less than Lorentz half-width at the earth’s surface, rather than the present width, because these channels can obtain information about variations in the ozone profile below the profile main-peak. The numerical experiments show that the method has a satisfactory precision in determining total ozone content, just about I percent error, and vertical distribution from the earth to 65 km space. In addition, some semi-analysis functions lor calculating backscattered ultraviolet and a relaxation equation are described in this paper. 展开更多
关键词 OZONE satisfactory ultraviolet CALCULATING INFRARED RELAXATION LORENTZ determining weighting FIGURE
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Angle Dependence Analysis Method to Determine SNRArc Applied to GNSSMRSea Level Retrieval 被引量:6
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作者 Xiaolei WANG Xiufeng HE +2 位作者 Qin ZHANG Mingfeng SONG Zijin NIU 《Journal of Geodesy and Geoinformation Science》 2021年第2期14-26,共13页
The Global Navigation Satellite Systems(GNSS)broadcast radio signals are continuously at two or more frequencies in the L-band,and the multipath signals from sea surface recorded by off-the-shelf geodetic receivers ha... The Global Navigation Satellite Systems(GNSS)broadcast radio signals are continuously at two or more frequencies in the L-band,and the multipath signals from sea surface recorded by off-the-shelf geodetic receivers have been demonstrated they can be used to estimate sea level,using a technology called GNSS multipath reflectometry(GNSS-MR).Before proceeding to estimate reflection parameters,the azimuth range and elevation angle range are needed to be defined,as only with suitable azimuths and elevation angles the sensing zones can be guaranteed on water.So,this study presents an angle dependence analysis method to jointly select the azimuth range and elevation angle range based on wavelet analysis which can describe the nonstationary power of different sinusoidal oscillations changed with elevation angle.The key of this method is to use one grid model to screen the spectrum power of multipath oscillation on different elevation angles and azimuths in this work.Then the elevation angles and the azimuths can be determined by searching grids with greater power.The GPS and GLONASS data of two MultiGNSS Experiment(MGEX)stations named BRST and MAYG was analyzed and used to retrieve.Firstly,the angle dependence analysis was carried out to determine the elevation range and azimuth range.Secondly,the sea levels were retrieved from individual signals.Finally,the retrievals of individual signals are combined to form a 10-min sea level retrieval series.The RMSEs of the combined retrievals are both less than 15 cm.The results show the effectiveness of the selection of angle range based on the angle dependence analysis method. 展开更多
关键词 GNSS-MR sea level azimuth determination elevation angle determination multi-GNSS combination
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Application of ^(241)Am EDXRF to Determine Heavy Rare Earths in RE Separation Processes by Solvent Extraction
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作者 贾江涛 马小桃 +2 位作者 严纯华 廖春生 李标国 《Journal of Rare Earths》 SCIE EI CAS CSCD 1997年第4期68-72,共5页
Applicationof241AmEDXRFtoDetermineHeavyRareEarthsinRESeparationProcesesbySolventExtractionJiaJiangtao(贾江涛),... Applicationof241AmEDXRFtoDetermineHeavyRareEarthsinRESeparationProcesesbySolventExtractionJiaJiangtao(贾江涛),MaXiaotao(马小桃),Ya... 展开更多
关键词 RARE earths EDXRF SOLVENT EXTRACTION HRE determination
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