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Performance enhancement of a viscoelastic bistable energy harvester using time-delayed feedback control
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作者 黄美玲 杨勇歌 刘洋 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第6期142-154,共13页
This paper focuses on the stochastic analysis of a viscoelastic bistable energy harvesting system under colored noise and harmonic excitation, and adopts the time-delayed feedback control to improve its harvesting eff... This paper focuses on the stochastic analysis of a viscoelastic bistable energy harvesting system under colored noise and harmonic excitation, and adopts the time-delayed feedback control to improve its harvesting efficiency. Firstly, to obtain the dimensionless governing equation of the system, the original bistable system is approximated as a system without viscoelastic term by using the stochastic averaging method of energy envelope, and then is further decoupled to derive an equivalent system. The credibility of the proposed method is validated by contrasting the consistency between the numerical and the analytical results of the equivalent system under different noise conditions. The influence of system parameters on average output power is analyzed, and the control effect of the time-delayed feedback control on system performance is compared. The output performance of the system is improved with the occurrence of stochastic resonance(SR). Therefore, the signal-to-noise ratio expression for measuring SR is derived, and the dependence of its SR behavior on different parameters is explored. 展开更多
关键词 energy harvesting BISTABILITY stochastic averaging method stochastic resonance time-delayed feedback control
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Comparison of the City Water Consumption Short-Term Forecasting Methods 被引量:7
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作者 刘洪波 张宏伟 《Transactions of Tianjin University》 EI CAS 2002年第3期211-215,共5页
There are a lot of methods in city water consumption short-term forecasting both inside and outside the country. But among these methods there exist many advantages and shortcomings in model establishing, solving and ... There are a lot of methods in city water consumption short-term forecasting both inside and outside the country. But among these methods there exist many advantages and shortcomings in model establishing, solving and predicting accuracy, speed, applicability. This article draws lessons from other realm mature methods after many years′ study. It′s systematically studied and compared to predict the water consumption in accuracy, speed, effect and applicability among the time series triangle function method, artificial neural network method, gray system theories method, wavelet analytical method. 展开更多
关键词 city water consumption short-term forecasting method comparison APPLICABILITY
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Comparison of Crop Model Validation Methods 被引量:3
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作者 CAO Hong-xin Jim Scott Hanan +11 位作者 LIU Yan LIU Yong-xia YUE Yan-bin ZHU Da-wei LU Jian- fei SUNJin-ying SHI Chun-lin GE Dao-kuo WEI Xiu-fang YAO An-qing TIAN Ping-ping BAO Tai-lin 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2012年第8期1274-1285,共12页
In this paper, the many indices used in validation of crop models, such as RMSE (root mean square errors), Sd (standard error of absolute difference), da (mean absolute difference), dap (ratio of da to the mean... In this paper, the many indices used in validation of crop models, such as RMSE (root mean square errors), Sd (standard error of absolute difference), da (mean absolute difference), dap (ratio of da to the mean observation), r (correlation), and R2 (determination coefficient), are compared for the same rice architectural parameter model, and their advantages and disadvantages are analyzed. A new index for validation of crop models, dap between the observed and the simulated values, is proposed, with dap〈5% as the suggested standard for precision of crop models. The different kinds of validation methods in crop models should be combined in the following aspects:(1) calculating da and dap; (2) calculating the RMSE or Sd; (3) calculating r and R2, at the same time, plotting 1:1 diagram. 展开更多
关键词 crop models validation methods comparison
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Comparison of Methods for Estimating Reference Crop Evapotranspiration in Beijing 被引量:1
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作者 Cao Yajie Shi Youyu +1 位作者 Mo Nannan Li Xin 《Meteorological and Environmental Research》 CAS 2019年第6期72-74,78,共4页
Based on the meteorological data from 1951 to 2015 in Beijing,the reference crop evapotranspiration(ET_0)in Beijing was estimated using the FAO 56 Penman-Monteith method,the FAO PPP-17 Penman method,the Hargreaves met... Based on the meteorological data from 1951 to 2015 in Beijing,the reference crop evapotranspiration(ET_0)in Beijing was estimated using the FAO 56 Penman-Monteith method,the FAO PPP-17 Penman method,the Hargreaves method,and the Priestley-Taylor method.The results showed that the monthly and annual changing trends of ET0 estimated by the four methods are basically the same.In general,the ET0 values estimated by the Hargreaves method are the closest to those of the standard method FAO 56 Penman-Monteith,while the difference between the FAO PPP-17 Penman method and the standard method is the biggest.The Hargreaves method is the most suitable method for the estimation of ET0 in Beijing. 展开更多
关键词 REFERENCE CROP EVAPOTRANSPIRATION ESTIMATION method comparison
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Research on Comparison and Evaluation Studies of Several Smoothing Denoising Method Based on γ-ray Spectrum Detector 被引量:1
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作者 Jian-Feng He Fang Fang +2 位作者 Yao-Zong Yang Yue-Shun He Bin Tang 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2013年第2期7-11,共5页
The extraction of spectral parameters is very difficult because of the limited energy resolution for NaI (TI) gamma-ray detectors. For statistical fluctuation of radioactivity under complex environment, some smoothi... The extraction of spectral parameters is very difficult because of the limited energy resolution for NaI (TI) gamma-ray detectors. For statistical fluctuation of radioactivity under complex environment, some smoothing filtering methods are proposed to solve the problem. These methods include adopting method of arithmetic moving average, center of gravity, least squares of polynomial, slide converter of discrete funcion convolution etc. The process of spectrum data is realized, and the results are assessed in H/FWHM( Peak High/Full Width at Half Maximum) and peak area based on the Matlab programming. The results indicate that different methods smoothed spectrum have respective superiority in different ergoregion, but the Gaussian function theory in discrete function convolution slide method is used to filter the complex y-spectrum on Embedded system nlatform, and the statistical fluctuation of y-snectrum filtered wall. 展开更多
关键词 T-spectrum data-processing smoothing denoising method comparison and evaluation matlabprogramming
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Methods Comparison for Microsatellite Marker Development:Different Isolation Methods,Different Yield Efficiency 被引量:1
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作者 ZHAN Aibin BAO Zhenmin HU Xiaoli LU Wei HU Jingjie 《Journal of Ocean University of China》 SCIE CAS 2009年第2期161-165,共5页
Microsatellite markers have become one kind of the most important molecular tools used in various researches. A large number of microsatellite markers are required for the whole genome survey in the fields of molecula... Microsatellite markers have become one kind of the most important molecular tools used in various researches. A large number of microsatellite markers are required for the whole genome survey in the fields of molecular ecology,quantitative genetics and genomics. Therefore,it is extremely necessary to select several versatile,low-cost,efficient and time-and labor-saving methods to develop a large panel of microsatellite markers. In this study,we used Zhikong scallop(Chlamys farreri) as the target species to compare the efficiency of the five methods derived from three strategies for microsatellite marker development. The results showed that the strategy of constructing small insert genomic DNA library resulted in poor efficiency,while the microsatellite-enriched strategy highly improved the isolation efficiency. Although the mining public database strategy is time-and cost-saving,it is difficult to obtain a large number of microsatellite markers,mainly due to the limited sequence data of non-model species deposited in public databases. Based on the results in this study,we recommend two methods,microsatellite-enriched library construction method and FIASCO-colony hybridization method,for large-scale microsatellite marker development. Both methods were derived from the microsatellite-enriched strategy. The experimental results obtained from Zhikong scallop also provide the reference for microsatellite marker development in other species with large genomes. 展开更多
关键词 MICROSATELLITE marker development isolation efficiency method comparison SCALLOP
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Quantitative comparison of cranial approaches in the anatomy laboratory: A neuronavigation based research method 被引量:1
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作者 Francesco Doglietto Jimmy Qiu +7 位作者 Mayoorendra Ravichandiran Ivan Radovanovic Francesco Belotti Anne Agur Gelareh Zadeh Marco Maria Fontanella Walter Kucharczyk Fred Gentili 《World Journal of Methodology》 2017年第4期139-147,共9页
AIMTo describe the development and validation of a novel neuronavigation-based method, which allows the quan-tification of the anatomical features that define anapproach, as well as real-time visualization of the surg... AIMTo describe the development and validation of a novel neuronavigation-based method, which allows the quan-tification of the anatomical features that define anapproach, as well as real-time visualization of the surgicapyramid. METHODSThe method was initially developed with commercially-available hardware for coordinate collection (a digitizerand a frameless navigation system) and software forvolume rendering; dedicated neuronavigation software (ApproachViewer, part of GTx-UHN) was then developed. The accuracy of measurements and the possibility of volumetric rendering of surgical approaches simulated in a phantom were compared among three different methods and commercially-available radiological software. In the anatomy laboratory, ApproachViewer was applied to the comparative quantitative analysis of multiple neurosurgical approaches and was used by many surgeons who were untrained for the research method.RESULTSThe accuracy of ApproachViewer is comparable to com-mercially-available radiological software. In the anatomy laboratory, the method appears versatile. The system can be easily used after brief training. ApproachViewer allows for real-time evaluation and comparison of surgical approaches, as well as post-dissection analyses of collected data. The accuracy of the method depends on the navigation registration: with a 1-2 mm registration error, it is adequate for evaluation and comparison of most neurosurgical approaches.CONCLUSIONThis new research method and software allows semi-automated visualization, quantifcation, and comparison of neurosurgical approaches in the anatomy laboratory. 展开更多
关键词 Anatomical study comparison Neurosurgical approach Quantifcation Research method 3D rendering
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The Comparison between Audio-lingual Method and Communicative Language Teaching in the Foreign Language Teaching 被引量:1
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作者 张瑜 张汉伟 《海外英语》 2013年第5X期15-16,23,共3页
To increase the efficiency of teaching and improve the quality of teaching, it is necessary to learn the English teaching methodology and put the theory into practice. Audio-lingual Method and Communicative Language T... To increase the efficiency of teaching and improve the quality of teaching, it is necessary to learn the English teaching methodology and put the theory into practice. Audio-lingual Method and Communicative Language Teaching are very important methods in English language teaching. In this essay, I made a comparison and analysis based on their theories and practices. It is beneficial for us to proceed from the reality and use these methods appropriately. 展开更多
关键词 comparison Audio-lingual method COMMUNICATIVE lang
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Performance Comparison of Two Efficient Genomic Selection Methods(gsbay & MixP ) Applied in Aquacultural Organisms
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作者 SU Hailin LI Hengde +2 位作者 WANG Shi WANG Yangfan BAO Zhenmin 《Journal of Ocean University of China》 SCIE CAS CSCD 2017年第1期137-144,共8页
Genomic selection is more and more popular in animal and plant breeding industries all around the world, as it can be applied early in life without impacting selection candidates. The objective of this study was to br... Genomic selection is more and more popular in animal and plant breeding industries all around the world, as it can be applied early in life without impacting selection candidates. The objective of this study was to bring the advantages of genomic selection to scallop breeding. Two different genomic selection tools Mix P and gsbay were applied on genomic evaluation of simulated data and Zhikong scallop(Chlamys farreri) field data. The data were compared with genomic best linear unbiased prediction(GBLUP) method which has been applied widely. Our results showed that both Mix P and gsbay could accurately estimate single-nucleotide polymorphism(SNP) marker effects, and thereby could be applied for the analysis of genomic estimated breeding values(GEBV). In simulated data from different scenarios, the accuracy of GEBV acquired was ranged from 0.20 to 0.78 by Mix P; it was ranged from 0.21 to 0.67 by gsbay; and it was ranged from 0.21 to 0.61 by GBLUP. Estimations made by Mix P and gsbay were expected to be more reliable than those estimated by GBLUP. Predictions made by gsbay were more robust, while with Mix P the computation is much faster, especially in dealing with large-scale data. These results suggested that both algorithms implemented by Mix P and gsbay are feasible to carry out genomic selection in scallop breeding, and more genotype data will be necessary to produce genomic estimated breeding values with a higher accuracy for the industry. 展开更多
关键词 GENOMIC SELECTION SCALLOP BREEDING method comparison
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Quantitative comparison screening of seismological indexes and research on the integrated prediction method in North China
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作者 周翠英 朱元清 +3 位作者 王红卫 梁凯莉 李平 郭爱香 《Acta Seismologica Sinica(English Edition)》 CSCD 1999年第2期232-237,共6页
关键词 comparison screening method quantitative selecting SEISMOLOGY parameters INTEGRATED Prediction
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The Comparison of Tasked-based Teaching Method and Situation Teaching Method in Lexical Learning in Senior High Language Teaching 被引量:1
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作者 李文君 《海外英语》 2021年第2期269-270,共2页
there are many teaching methods in current teaching procedures,such as the whole language teaching method;communicative teaching method;cooperation teaching method;situation teaching method;tasked-based teaching metho... there are many teaching methods in current teaching procedures,such as the whole language teaching method;communicative teaching method;cooperation teaching method;situation teaching method;tasked-based teaching method;content-based teaching method;competence-based teaching method multiple intelligence teaching method and other teaching methods.This article depicts the usage and comparison of the tasked-based teaching methods and situation teaching method in lexical learning in senior high language leaching.This article first talks about the definition and feature of these two teaching methods.Then through observing the students using different methods,I aim to compare these two methods in order to find out the similarities and differences between them when students are learning vocabulary.Making further study on the teaching methods,I would like to take good advantage of them in lexical learning in senior high classes in hope that we teachers can inspire students'thinking,arouse their desire,active the atmosphere and help them have a better and simpler command of the vocabulary they obtained in the class. 展开更多
关键词 situation teaching tasked-based teaching method lexical learning comparison
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Comparison of Four Diagnostic Tests Methods for the Detection of Dengue Virus Non-Structural-1 Antigen and IgM/IgG Antibodies
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作者 Moses N. Ikegbunam Ifeyinwa T.O. Onochie-Igbinedion +5 位作者 Nzube F. Ekpunobi Abone Harrison Enyi Emmanuel Simon Nkpeh Ushie Micheal U. Adiukwu Charles O. Esimone 《Journal of Biosciences and Medicines》 2022年第5期179-190,共12页
Objectives: Dengue virus (DENV) infection is a mosquito-borne disease that stands out as one of the major public health issues and has a wide-ranging geographical distribution throughout the tropics and subtropics. Th... Objectives: Dengue virus (DENV) infection is a mosquito-borne disease that stands out as one of the major public health issues and has a wide-ranging geographical distribution throughout the tropics and subtropics. The general alarming increase in the number of cases over the last two decades can be attributed to an extent by the change in national practices to keeping records and reporting dengue to the Ministries of Health, and WHO. Dengue diagnosis is routinely carried out by detection of dengue virus (DENV) antigen NS1 (Non-structural Antigen 1) and/or anti-DENV IgM/IgG antibodies using enzyme-linked immunosorbent assays (ELISAs) and rapid diagnostic tests (RDTs). This study compared the performance of three RDTs and one ELISA used for dengue diagnosis in southeastern, Nigeria. Design: This study adopted a cross-sectional design that included prospective hospital-based surveillance of cases among febrile participants attending two major health facilities within the southeastern region of Nigeria. In this study, 338 HIV-infected participants from two teaching hospitals in Nigeria’s southeast were systematically tested for Dengue with four methods: NS1 RDT, IgG RDT, IgM RDT, and NS1 ELISA. Their specificities and sensitivities were compared, as well as their level of concordance. Their respective performances were also evaluated using the Receivers Operational curve (ROC). Results: Out of the 338 patients, the dengue prevalence from the four dengue diagnostic methods Dengue virus NS1 ELISA, NS1 RDT, IgM and IgG seropositivity were 8.9%, 0.6%, 5.6%, and 8.0%, respectively. The Dengue IgM RDT test indicated 36.8% sensitivity, 92.8% specificity, the IgG anti-dengue specific test indicated 29.6% sensitivity, 92.9% specificity and the dengue NS1 RDT test indicated 3.3% sensitivity, 99.4% specificity when compared with the Dengue NSI Elisa test method as a reference method. Conclusion: The use of NSI ELISA for DENV diagnosis showed good performance and the RDTs showed, to an extent, reliable results compared with ELISA. However, diagnostic laboratories should be aware of performance variations across tests and the possibilities of cross-reactivity that may affect results. 展开更多
关键词 Dengue Virus Diagnosis methods comparison Performance Southeastern Nigeria
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Comparison of Three Methods in Extracting Coherent Modes from a Doppler Backscatter System
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作者 张小辉 刘阿娣 +7 位作者 周楚 胡健强 王明远 俞昌旋 刘万东 李弘 兰涛 谢锦林 《Chinese Physics Letters》 SCIE CAS CSCD 2015年第12期92-95,共4页
We compare three different methods to extract coherent modes from Doppler backscattering (DBS), which are center of gravity (COG) of the complex amplitude spectrum, spectrum of DBS phase derivative (phase derivat... We compare three different methods to extract coherent modes from Doppler backscattering (DBS), which are center of gravity (COG) of the complex amplitude spectrum, spectrum of DBS phase derivative (phase derivative method), and phase spectrum, respectively. These three methods are all feasible to extract coherent modes, for example, geodesic acoustic mode oscillation. However, there are stilI differences between dealing with high frequency modes (several hundred kHz) and low frequency modes, (several kHz) hiding in DBS signal. There is a significant amount of power at low frequencies in the phase spectrum, which can be removed by using the phase derivative method and COG. High frequency modes are clearer by using the COO and the phase derivative method than the phase spectrum. The spectrum of DBS amplitude does not show the coherent modes detected by using COG, phase derivative method and phase spectrum. When two Doppler shifted peaks exist, coherent modes and their harmonics appear in the spectrum of DBS amplitude, which are introduced by the DBS phase. 展开更多
关键词 DBS comparison of Three methods in Extracting Coherent Modes from a Doppler Backscatter System COG Figure
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Comparison of K_(IC) Values for SiC Whisker Reinforced Ceramic Composites Obtained by Using Various Methods
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作者 Tingquan LEI Guangyong LIN +1 位作者 Shuangxi WANG and Yu ZHOU (Dept. of Metals and Technology, Harbin Institute of Technology, Harbin, 150001, China)(To whom correspondence should be addressed) 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 1994年第5期331-340,共10页
The fracture toughness (KIC) values determined by indentation microfracture method (IM ) for SiC whisker reinforced Al2O3 and ZrO2 based composites were calculated with different IM equations and compared with those o... The fracture toughness (KIC) values determined by indentation microfracture method (IM ) for SiC whisker reinforced Al2O3 and ZrO2 based composites were calculated with different IM equations and compared with those obtained by singte edge notched beam (SENB) technique. Experimental results show that the KIC (IM) values calculated with different equations are quite different one from another. For composites without phase transformable components the KIC (IM) and KIC (SENB) values are practically on the same level, but for composites with phase transformable components (partially stabilized zirconia) the KIC (SENB) values are always higher than KIC (IM). This is because that the IM method can not reveal sensitively the toughening effect due to dynamic t-m transformation of ZrO2 as the SENB method does. The accuracy of the IM method depends on the Suitability of the IM equations and was evaluated for the materials used in this investigation. Two new IM equations are suggested with which the KIC (IM ) values can be obtained very close to KIC (SENB) values for composites having phase transformable components. 展开更多
关键词 SiC Values for SiC Whisker Reinforced Ceramic Composites Obtained by Using Various methods comparison of K IC
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A randomised controlled comparison of injection,thermal,and mechanical endoscopic methods of haemostasis on mesenteric vessels 被引量:8
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作者 C C Hepworth S S Kadirkamanathan +1 位作者 F Gong C P Swain 《World Journal of Gastroenterology》 SCIE CAS CSCD 1998年第3期71-71,共1页
Arandomisedcontroledcomparisonofinjection,thermal,andmechanicalendoscopicmethodsofhaemostasisonmesentericves... Arandomisedcontroledcomparisonofinjection,thermal,andmechanicalendoscopicmethodsofhaemostasisonmesentericvesselsCCHepworth1,S... 展开更多
关键词 MESENTERIC comparison ENDOSCOPIC HAEMOSTASIS mechanical CONTROLLED methods of RANDOMISED VESSELS
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A Comparison between Three Methods for Transverse shielding Design of High Energy Heavy Ion Accelerator
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作者 Zhu Lianfang Chen Xuebing and Su Youwu 《IMP & HIRFL Annual Report》 1995年第0期95-95,共1页
A Comparison between Three Methods for Transverse shielding Design of High Energy Heavy Ion AcceleratorAComp... A Comparison between Three Methods for Transverse shielding Design of High Energy Heavy Ion AcceleratorAComparisonbetweenThre... 展开更多
关键词 SHIELDING comparison Design ENERGY HEAVY High ION methods THREE TRANSVERSE
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Comparison between Two Kinds of Methods of Locating Acupoints 
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作者 Ding Yidan,Li Jingming(Medical College of Jinan University) 《中国针灸》 CAS CSCD 北大核心 1995年第S2期375-375,共1页
ComparisonbetweenTwoKindsofMethodsofLocatingAcupoints¥DingYidan,LiJingming(MedicalCollegeofJinanUniversity)T... ComparisonbetweenTwoKindsofMethodsofLocatingAcupoints¥DingYidan,LiJingming(MedicalCollegeofJinanUniversity)Theproportionalmea... 展开更多
关键词 comparison between Two Kinds of methods of Locating Acupoints
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Comparison of three methods for paternity test
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《中国输血杂志》 CAS CSCD 2001年第S1期384-,共1页
关键词 comparison of three methods for paternity test
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Comparison of Extraction Methods for Total Alkaloids from Abrus Cantoniensis Hance
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作者 Mengyao LIN Qiumeng WEI +7 位作者 Xiaoxia HUANG Jiaming WANG Suoyi HUANG Luyao WANG Yan LIU Gongxiao MO Xunjie LIANG Xiaoting MA 《Medicinal Plant》 2017年第2期19-21,共3页
[Objectives] To compare different extraction methods for total alkaloids from Abrus Cantoniensis Hance taking chloroform as solvent. [Methods] The ethanol extraction method,ultrasonic extraction method,acid water extr... [Objectives] To compare different extraction methods for total alkaloids from Abrus Cantoniensis Hance taking chloroform as solvent. [Methods] The ethanol extraction method,ultrasonic extraction method,acid water extraction method,and Soxhlet extraction method were used to extract total alkaloids,and the total alkaloids of Abrus Cantoniensis Hance were measured at 238 nm wavelength. [Results] The extraction rate of ethanol extraction method was 14. 76 mg/100 g; the extraction rate of ultrasonic extraction method was 56. 85 mg/100 g; the extraction rate of acid water extraction method was 56. 63 mg/100 g; the extraction rate of Soxhlet extraction method was 58. 19 mg/100 g.[Conclusions]Results indicate that Soxhlet extraction method can obtain the highest extraction rate. 展开更多
关键词 TOTAL ALKALOIDS Abrus Cantoniensis Hance EXTRACTION methodS comparison
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Design and analysis of active disturbance rejection control for time-delay systems using frequency-sweeping
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作者 WANG Yongshuai CHEN Zengqiang +1 位作者 SUN Mingwei SUN Qinglin 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2023年第2期479-491,共13页
For the typical first-order systems with time-delay,this paper explors the control capability of linear active disturbance rejection control(LADRC).Firstly,the critical time-delay of LADRC is analyzed using the freque... For the typical first-order systems with time-delay,this paper explors the control capability of linear active disturbance rejection control(LADRC).Firstly,the critical time-delay of LADRC is analyzed using the frequency-sweeping method and the Routh criterion,and the stable time-delay interval starting from zero is accurately obtained,which reveals the limitations of general LADRC on large time-delay.Then in view of the large time-delay,an LADRC controller is developed and verified to be effective,along with the robustness analysis.Finally,numerical simulations show the accuracy of critical time-delay,and demonstrate the effectiveness and robustness of the proposed controller compared with other modified LADRCs. 展开更多
关键词 active disturbance rejection control frequencysweeping method critical time-delay Routh criterion system with large time-delay
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