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Retrieval of Total Suspended Matters Using Field Spectral Data in Shitoukoumen Reservoir,Jilin Province,Northeast China 被引量:2
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作者 XU Jingping ZHANG Bai +4 位作者 LI Fang SONG Kaishan WANG Zongming LIU Dianwei ZHANG Guangxin 《Chinese Geographical Science》 SCIE CSCD 2009年第1期77-82,共6页
From August to October in 2006,three times of field spectral measurements with a Field Spec FR spectroradiometer(Analytical Spectral Devices,Inc.,USA) were carried out in Shitoukoumen Reservoir,Jilin Province,Northeas... From August to October in 2006,three times of field spectral measurements with a Field Spec FR spectroradiometer(Analytical Spectral Devices,Inc.,USA) were carried out in Shitoukoumen Reservoir,Jilin Province,Northeast China. Owing to the serious soil and water loss in the upstream,reflectance curves of the reservoir were characterized by high concentrations of total suspended matter(TSM) . Extending the spectral analysis to 1200nm in the near-infrared band,this research revealed an obvious reflectance peak around 1070nm which was caused by the strong backscattering of high TSM. The method of partial least squares(PLS) regression was applied to retrieving the TSM. Reflectance in two spectral bands,i.e.,675-948nm and 1029-1105nm,were used as variables to develop PLS models. Traditional linear regression,first derivative model and logarithmic model were also used for the comparison of different models. Results showed that the PLS model based on Rrs(675) -Rrs(948) gave out best results with high precision and stability. Although the PLS model based on Rrs(1029) -Rrs(1105) did not have an outstanding performance due to lots of noise,the reflectance peak in the near-infrared band was an important TSM feature and its efficient exploitation would have a considerable significance in TSM remote sensing. 展开更多
关键词 total suspended matter partial least squared (PLS) regression remote sensing Shitoukoumen Reservoir
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A New Design Approach for Nearly Linear Phase Stable IIR Filter using Fractional Derivative 被引量:1
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作者 Nikhil Agrawal Anil Kumar Varun Bajaj 《IEEE/CAA Journal of Automatica Sinica》 EI CSCD 2020年第2期527-538,共12页
In this paper,a new design method for digital infinite impulse response(IIR)filters with nearly linear-phase response is presented using fractional derivative constraints(FDCs).In the proposed method,design problem of... In this paper,a new design method for digital infinite impulse response(IIR)filters with nearly linear-phase response is presented using fractional derivative constraints(FDCs).In the proposed method,design problem of an IIR frlter is constructed as the minimization of phase error between the desired and designed phase response of an allpass filter(APF)such that the designed lowpass filter(LPF)or highpass frlter(HPF)yields less passband(ep),and stopband errors(es)with optimal stopband attenuation(As).In order to have accurate passband(pb)response,FDCs are imposed on appropriate reference frequency,where the optimality of these FDCs are ensured by using a new greedy based sorting mechanism.The simulated results reflect the efficiency of the proposed method in term of improved passband response along with better transition width.However,small reduction in^is observed within the allowable limit,when compared to noin-fractional design approach,but the designed filter remains immune to wordlength(WL)effect. 展开更多
关键词 Fractional derivative constraint(FDC) infinite impulse response(IIR)filter least squared linear phase QUANTIZATION
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Analysis of Phytochemical Constituents of Zuogui Wan in Rat Serum and its Effects on Early Embryonic Development of Mice 被引量:3
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作者 Ya-Fei Guo Kai-Xia Xu +4 位作者 Jie-Wei Hong Shuang Yin Xin Niu Qian-Jin Feng Ying-Li Wang 《World Journal of Traditional Chinese Medicine》 2020年第3期324-330,共7页
Objective:Zuogui Wan(ZGW)has been used as a typical prescription for tonifying kidney essence in traditional Chinese medicine.The objective of this study is to elucidate the phytochemical constituents of ZGW-treated r... Objective:Zuogui Wan(ZGW)has been used as a typical prescription for tonifying kidney essence in traditional Chinese medicine.The objective of this study is to elucidate the phytochemical constituents of ZGW-treated rat serum(ZGWRS)using ultra-performance liquid chromatography-electrospray ionization/quadrupole-time-of-flight high-definition mass spectrometry(UPLC-ESI-Q-TOF-MS).Methods:ZGW was administered to rats,and the phytochemical constituents in rat serum were determined using UPLC-ESI-Q-TOF-MS.MetaboLynx analysis in negative ion mode was adopted to characterize the chemical constituents of ZGWRS.Orthogonal partial least squares discriminant analysis was applied for the discovery of constituents of ZGW that entered the serum of rats.The fertilized eggs collected from the same experiment were randomly divided into four groups,including the normal,40 mmol/L glucose,40 mmol/L glucose 5%control rat serum,and 40 mmol/L glucose 5%ZGWRS groups.They were cultivated at 37°C and 5%CO2 in a saturated humidity CO2 incubator.The blastocyst rate and two-cell rate were used to evaluate the effects of ZGWRS on embryonic development.Results:Thirteen constituents were identified in the ZGWRS,among which sweroside,loganin,morroniside,loganic acid,and 8-epiloganic acid were from Fructus Corni(Shan Zhu Yu).5-Hydroxymethyl-2-furfural-glucuronide,2-H-5-hydroxymethyl-2-furfural-glucuronide,3-hydroxy-2,6,6-trimethyl-1-cyclohexene-1-carboxylic acid,andβ-D-ribofuranuronic acid methyl ester triacetate were from Radix Rehmanniae Preparata(Shu Di Huang).Coumaric acid was from Fructus Lycii(Gou Qi Zi).Kaempferol-3-beta-O-glucuronide and cuscutamine were from Semen Cuscutae(Tu Si Zi).The embryonic development was significantly inhibited using 40 mmol/L glucose.Compared with the normal group,the blastocyst rate of the glucose group was decreased.The blastocyst rate of the 40 mmol/L glucose 5%ZGWRS group was significantly higher than that of the glucose group,indicating that ZGWRS negates the effect of glucose on mouse embryonic development.Conclusion:The results verified that a rapid and robust UPLC-ESI-Q-TOF-MS-based platform had been successful for identifying multiple constituents of ZGW.ZGWRS is rich in active constituents of iridoid glycosides.The results of this study also showed that ZGWRS could negate the effect of glucose on mouse embryonic development. 展开更多
关键词 Orthogonal partial least squared discriminant analysis ultra-performance liquid chromatograph-electrospray ionization/quadrupole-time-of-flight high-definition mass spectrometry Zuogui Wan
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