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基于Lucidshape的AFS光型分析
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作者 郑尧刚 李书伟 刘绍娜 《农业装备与车辆工程》 2012年第12期4-6,共3页
自适应前照灯系统(AFS)能够根据汽车夜间行驶时的速度、方向盘的转角、路面状况和天气条件自动地调整前照灯旋转角度来改变光型,提高驾驶的安全性和舒适性。主要通过Lucidshape光型分析软件建立投影型前照灯模型;模拟、分析AFS光型特点... 自适应前照灯系统(AFS)能够根据汽车夜间行驶时的速度、方向盘的转角、路面状况和天气条件自动地调整前照灯旋转角度来改变光型,提高驾驶的安全性和舒适性。主要通过Lucidshape光型分析软件建立投影型前照灯模型;模拟、分析AFS光型特点,有利于灯具的设计,提高产品效率和质量,缩短AFS开发周期。 展开更多
关键词 AFS Lucidshape 光型分析 投影前照灯
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非分光型CO/HC气体分析仪故障分析及排除
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作者 贾志新 鲍远通 《汽车技术》 北大核心 2003年第5期42-44,共3页
汽车综合性能检测站和汽车二级维护企业都配置了CO/HC气体分析仪,以MEXA-324F型CO/HC气体分析仪为例,阐述了分析仪的检测原理、结构、主要操作、机械校准、故障分析及排除方法。在分析仪故障及排除中,介绍了以下几种故障的现象、故障原... 汽车综合性能检测站和汽车二级维护企业都配置了CO/HC气体分析仪,以MEXA-324F型CO/HC气体分析仪为例,阐述了分析仪的检测原理、结构、主要操作、机械校准、故障分析及排除方法。在分析仪故障及排除中,介绍了以下几种故障的现象、故障原因及故障排除:一是仪表指针不动;二是仪表指针摆动不稳;三是指示值过大或过小等。 展开更多
关键词 非分CO/HC气体分析 汽车 综合性能检测 故障分析 故障排除
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基于热释电探测器DIGA数学模型 被引量:3
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作者 张永怀 刘君华 《光谱学与光谱分析》 SCIE EI CAS CSCD 北大核心 2004年第3期376-378,共3页
根据热释电探测器工作原理 ,对其使用特点进行了分析。在分光型红外气体分析器 (DIGA)设计原理基础上 ,建立了基于热释电探测器的红外气体分析系统输入输出数学模型。依据该模型研制了一个新型多组分红外气体分析器 ,并指出设计DIGA注... 根据热释电探测器工作原理 ,对其使用特点进行了分析。在分光型红外气体分析器 (DIGA)设计原理基础上 ,建立了基于热释电探测器的红外气体分析系统输入输出数学模型。依据该模型研制了一个新型多组分红外气体分析器 ,并指出设计DIGA注意的若干问题。应用表明 ,该模型对DIGA的设计、研究。 展开更多
关键词 热释电探测器 DIGA 数学模 红外气体分析 工作原理 设计
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Extraction of Soil Organic Matter Information by Multi-spectral Remote Sensing Based on Diverse Landforms 被引量:1
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作者 杨建锋 马军成 +1 位作者 王令超 樊鹏 《Agricultural Science & Technology》 CAS 2016年第7期1744-1748,共5页
Based on diverse landforms, the correlation between soil organic matter content and multi-spectral band of remote sensing image was analyzed in this pa- per. In addition, the inversion models were built for the soil o... Based on diverse landforms, the correlation between soil organic matter content and multi-spectral band of remote sensing image was analyzed in this pa- per. In addition, the inversion models were built for the soil organic matter content in different landforms. The results showed that the spectral reflectance was nega- tively related to soil organic matter content; linear regression analysis of remove was performed throughout the bands using SPSS. When the inversion models were built based on all the bands, better fitting effect was obtained. The precision of in- version models built based on different landforms was higher than those built re- gardless landforms. Compared with the actual value, the identification level of soil organic matter content was 91 65% under the allowable error was 7%. It indicated that the extraction of soil organic matter with inversion model that was built based on different landforrrs was feasible with higher precision. 展开更多
关键词 Landform type MULTI-SPECTRAL Regression analysis Soil organic matter
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Determination of Melamine by Infrared Spectroscopy Based on Nonlinear Modeling 被引量:1
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作者 张恒 高曼侠 +2 位作者 许兆棠 李文谦 王琪 《Agricultural Science & Technology》 CAS 2010年第8期133-136,共4页
[Objective] The aim was to develop a nonlinear model of quantitative analysis of melamine content by infrared spectroscopy and provide theoretical basis for the nondestructive detection of melamine. [Method] According... [Objective] The aim was to develop a nonlinear model of quantitative analysis of melamine content by infrared spectroscopy and provide theoretical basis for the nondestructive detection of melamine. [Method] According to dynamics,mathematical modeling and optimization theory,linear and nonlinear models were respectively set up by taking an absorption peak of 1 550 cm-1 as characteristic absorption peak. [Result] The correlation coefficient of nonlinear model was 0.922 7 and the recovery was 96%,which showed that the nonlinear model was more accurate than linearity model with correlation coefficient of 0.904 9 and recovery of 557%. [Conclusion] It is feasible to determine melamine content by using the nonlinear model quantitatively. 展开更多
关键词 Infrared spectroscopy Quantitative analysis Nonlinear model MELAMINE
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Improvement of Urban Impervious Surface Estimation in Shanghai Using Landsat7 ETM+ Data 被引量:7
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作者 YUE Wenze 《Chinese Geographical Science》 SCIE CSCD 2009年第3期283-290,共8页
This paper explores the potential to improve the impervious surface estimation accuracy using a multi-stage approach on the basis of vegetation-impervious surface-soil (V-I-S) model. In the first stage of Spectral Mix... This paper explores the potential to improve the impervious surface estimation accuracy using a multi-stage approach on the basis of vegetation-impervious surface-soil (V-I-S) model. In the first stage of Spectral Mixture Analysis (SMA) process, pixel purity index, a quantitative index for defining endmember quality, and a 3-dimensional endmember selection method were applied to refining endmembers. In the second stage, instead of obtaining impervious surface fraction by adding high and low albedo fractions directly, a linear regression model was built between impervious surface and high/low albedo using a random sampling method. The urban impervious surface distribution in the urban central area of Shanghai was predicted by the linear regression model. Estimation accuracy of spectral mixture analysis and impervious surface fraction were assessed using root mean square (RMS) and color aerial photography respectively. In comparison with three different research methods, this improved estimation method has a higher overall accuracy than traditional Linear Spectral Mixture Analysis (LSMA) method and the normalized SMA model both in root mean square error (RMSE) and standard error (SE). However, the model has a tendency to overestimate the impervious surface distribution. 展开更多
关键词 vegetation-impervious surface-soil model spectral mixture analysis impervious surface SHANGHAI
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On the Non-linear Motion of IGS Station 被引量:1
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作者 YAO Yibin 《Geo-Spatial Information Science》 2007年第4期240-244,共5页
With the daily SINEX files of the IGS, the time series of IGS stations are obtained using an independently developed software under generalized network adjustment models with coordinate patterns. From the time series,... With the daily SINEX files of the IGS, the time series of IGS stations are obtained using an independently developed software under generalized network adjustment models with coordinate patterns. From the time series, non-linear motions are found. With spectral analysis method, the variation frequency (annual period and semi-annual period) of the site velocity is found. Moreover, the empirical model of the velocity variation of the station has been established by regression analysis method based on the weekly solution coordinate series of the station. With respect to the velocity of the IGS tracking station, it was better to model the variation periodically or to give a velocity periodically using a piece-wise linear function rather than a linear variable to estimate its bias. 展开更多
关键词 IGS station NON-LINEAR spectral analysis empirical model
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FORECASTING THE MJO INDEX BASED ON SSA-AR
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作者 江志红 张勤 +1 位作者 朱红蕊 吴立广 《Journal of Tropical Meteorology》 SCIE 2011年第4期317-325,共9页
Experiments of forecasting daily bi-variate index of the tropical atmospheric Madden-Julian Oscillation (MJO) are performed in the context of adaptive filtering prediction models by combining the singular spectrum ana... Experiments of forecasting daily bi-variate index of the tropical atmospheric Madden-Julian Oscillation (MJO) are performed in the context of adaptive filtering prediction models by combining the singular spectrum analysis (SSA) with the autoregressive (AR) methods.the MJO index,a pair of empirical orthogonal function (EOF) time series,called RMM1 and RMM2,predicts by the combined statistical SSA and AR models:firstly,according to the index of historic observation decomposed by SSA and then reconstructed by selecting the first several components based on prominent variance contributions;after that,established an AR prediction model from the composite (scheme A) or built the forecast models for each of these selected reconstructed components,separately (Scheme B).Several experimental MJO index forecasts are performed based on the models.The results show that both models have useful skills of the MJO index forecast beyond two weeks.In some cases,the correlation coefficient between the observed and predicted index series stays above 0.5 in 20 leading days.The SSA-AR model,based on the reconstructed composite series,has better performance on MJO forecast than the AR model,especially for the leading time longer than 5 days.Therefore,if we build a real-time forecast system by the SSA-AR model,it might provide an applicable tool for the operational prediction of the MJO index. 展开更多
关键词 Madden-Julian Oscillation singular spectrum analysis autoregressive model
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Characterization of a novel rat cholangiocarcinoma cell culture model-CGCCA
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作者 Chun-Nan Yeh Kun-Ju Lin +5 位作者 Tsung-Wen Chen Ren-Ching Wu Lee-Cheng Tsao Ying-Tzu Chen Wen-Hui Weng Miin-Fu Chen 《World Journal of Gastroenterology》 SCIE CAS CSCD 2011年第24期2924-2932,共9页
AIM: TO characterize a culture model of rat CCA cells, which were derived from a transplantable TTA-induced CCA and designated as Chang Gung CCA (CGCCA). METHODS: The CGCCA cells were cultured at in vitro passage ... AIM: TO characterize a culture model of rat CCA cells, which were derived from a transplantable TTA-induced CCA and designated as Chang Gung CCA (CGCCA). METHODS: The CGCCA cells were cultured at in vitro passage 12 times on a culture dish in DMEM medium. To measure the doubling time, 103 cells were plated in a 96-well plate containing the growth medium. The cells were harvested 4 to 10 d after seeding, and a standard MTT assay was used to measure the growth. The phenotype of CACCA cell and xenograft was determined by immunohistochemical study. We also determine the chromosomal alterations of CGCCA, G-banding and spectral karyotyping studies were performed. The CGCCA cell line was transplanted into the nude mice for examining its tumorigenicity. 2-Deoxy-2-(18F)fluoro-D- glucose (FDG) autoradiography was also performed to evaluate the FDG uptake of the tumor xenograft. RESULTS: The doubling time for the CGCCA cell line was 32 h. After transplantation into nude mice, FDG autoradiography showed that the tumors formed at the cell transplantation site had a latency period of 4-6 wk with high FDG uptake excluding necrosis tissue. Moreover, immunohistochemical staining revealed prominent cytoplasmic expression of c-erb-B2, CK19, c-Met, COX-n, EGFR, MUC4, and a negative expression of K-ras. All data confirmed the phenotypic features of the CGCCA cell line coincide with the xenograft mice tumors, indicating cells containing the tumorigenicity of CCA originated from CCA. In addition, karyotypic band- ing analysis showed that the diploid (2n) cell status combines with ring and giant rod marker chromosomes in these clones; either both types simultaneously appeared or only one type of marker chromosome in a pair appeared in a cell. The major materials contained in the marker chromosome were primarily identified from chromosome 4. CONCLUSION: The current CGCCA cell line may be used as a non-K-ras effect CCA model and to obtain information and reveal novel pathways for CCA. Further applications regarding tumor markers or therapeutic targeting of CCA should be addressed accordingly. 展开更多
关键词 CHOLANGIOCARCINOMA Rat cell line Estab-lishment CHARACTERIZATION THIOACETAMIDE
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Simulation Analysis for Massive Deployment of Variable Renewables Employing an Optimal Power Generation Mix Model
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作者 Ryoichi Komiyama Saeko Shibata Yasumasa Fujii 《Journal of Energy and Power Engineering》 2013年第8期1604-1615,共12页
This paper develops a high time-resolution optimal power generation mix model in its time resolution of 10 minutes on 365 days by linear programming technique. The model allows us to analyse the massive deployment of ... This paper develops a high time-resolution optimal power generation mix model in its time resolution of 10 minutes on 365 days by linear programming technique. The model allows us to analyse the massive deployment of photovoltaic system and wind power generation in power system explicitly considering those short-term output variation. PV (photovoltaic) and wind output are estimated, employing meteorological database. Simulation results reveal that variable fluctuation derived from a high penetration level of those renewables is controlled by quick load following operation of natural gas combined cycle power plant, pumped-storage hydro power, stationary NAS (sodium and sulfur) battery and the output suppression control of PV and wind. It additionally turns out that the operational configuration of those technologies for the renewable variability differs significantly depending on those renewable output variations in each season and solving the seasonal electricity imbalance as well as the daily imbalance is important if variable renewables are massively deployed. 展开更多
关键词 BATTERIES power generation dispatch power generation planning power system economics power system simulation solar power generation wind power generation.
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Melanopsin-expressing retinal ganglion cell loss and behavioral analysis in the Thy1-CFP-DBA/2J mouse model of glaucoma 被引量:4
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作者 ZHANG Qi VUONG Helen +4 位作者 HUANG Xin WANG YanLing BRECHA Nicholas C. PU MingLiang GAO Jie 《Science China(Life Sciences)》 SCIE CAS 2013年第8期720-730,共11页
In this study, the role of melanopsin-expressing retinal ganglion cells (mRGCs) in the glaucoma-induced depressive behavioral response pattern was investigated. The CFP-D2 transgenic glaucoma animal model from five ... In this study, the role of melanopsin-expressing retinal ganglion cells (mRGCs) in the glaucoma-induced depressive behavioral response pattern was investigated. The CFP-D2 transgenic glaucoma animal model from five age groups was used in this study. Immunohistochemical labeling, quantitative analysis of mRGC morphology, open field test (OFT), and statistical analysis were used. In comparison with C57 BL/6 mice, the age-matched CFP-D2 mice had significantly elevated intraocular pressure (lOP). We observed parallel morphological changes in the retina, including a reduction in the density of cyan fluorescent protein- (CFP) expressing cells (cells mm^-2 at 2 months of age, 1309±26; 14 months, 878±30, P〈0.001), mRGCs (2 months, 48_+3; 14 months, 19±4, P〈0.001), Brn3b-expressing RGCs (2 months, 1283±80; 14 months, 950±31, P〈0.001), Brn-3b expressing mRGCs (5 months, 50.17%±5.5%; 14 months, 12.61%±3.8%, P〈0.001), and reduction in the dendritic field size of mRGCs (mm^2 at 2 months, 0.077±0.015; 14 months, 0.065±0.015, P〈0.05). CFP-D2 mice had hyperactive locomotor activity patterns based on OFT findings of the total distance traveled, number of entries into the center, and time spent in the center of the testing apparatus. The glaucoma induced hyperactive response pattern could be associated with dysfunctional mRGCs, most likely Brn-3b-positive mRGCs in CFP-D2 mice. 展开更多
关键词 pigmentary glaucoma Thyl-CFP-DBA/2J mouse retinal ganglion cells melanopsin-expressing retinal ganglion cells depression
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A variable differential consensus method for improving the quantitative near-infrared spectroscopic analysis 被引量:1
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作者 DU GuoRong CAI WenSheng SHAO XueGuang 《Science China Chemistry》 SCIE EI CAS 2012年第9期1946-1952,共7页
Consensus methods have presented promising tools for improving the reliability of quantitative models in near-infrared(NIR) spectroscopic analysis.A strategy for improving the performance of consensus methods in multi... Consensus methods have presented promising tools for improving the reliability of quantitative models in near-infrared(NIR) spectroscopic analysis.A strategy for improving the performance of consensus methods in multivariate calibration of NIR spectra is proposed.In the approach,a subset of non-collinear variables is generated using successive projections algorithm(SPA) for each variable in the reduced spectra by uninformative variables elimination(UVE).Then sub-models are built using the variable subsets and the calibration subsets determined by Monte Carlo(MC) re-sampling,and the sub-model that produces minimal error in cross validation is selected as a member model.With repetition of the MC re-sampling,a series of member models are built and a consensus model is achieved by averaging all the member models.Since member models are built with the best variable subset and the randomly selected calibration subset,both the quality and the diversity of the member models are insured for the consensus model.Two NIR spectral datasets of tobacco lamina are used to investigate the proposed method.The superiority of the method in both accuracy and reliability is demonstrated. 展开更多
关键词 near infrared spectroscopy multivariate calibration consensus model variable selection uninformative variable elim-ination successive projections algorithm
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Folding Model Analysis of Elastic Scattering of 11B from Light,Medium,and Heavy Nuclei
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作者 M.Aygun 《Communications in Theoretical Physics》 SCIE CAS CSCD 2016年第11期531-540,共10页
The elastic scattering angular distributions of z113 projectile on light, medium, and heavy target nuclei including 7Li, 9Be, 12C, 16O, 24,25,26Mg, 27Al, 28Si, 40Ca, 58Ni, 59Co, 60Ni, 197Au, 208Pb, and 209Bi have been... The elastic scattering angular distributions of z113 projectile on light, medium, and heavy target nuclei including 7Li, 9Be, 12C, 16O, 24,25,26Mg, 27Al, 28Si, 40Ca, 58Ni, 59Co, 60Ni, 197Au, 208Pb, and 209Bi have been analyzed at various incident energies. The theoretical results have been obtained by using two different nuclear potentials within the framework of the optical model (OM). Firstly, the double folding potential for real part and the Wood-Saxon (WS) potential for imaginary part have been applied. Secondly, the calculations with double folding potential for both real and imaginary part have been performed and compared with the experimental data. It has been seen that the results are in very good agreement with the experimental data. Also, the volume integrals and cross-sections for each reaction have been obtained. Finally, a new and simple formula for the imaginary potential depth has been derived to clarify the nuclear interactions of 11B nucleus at low energy reactions. 展开更多
关键词 optical model elastic scattering
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Study on swelling model and thermodynamic structure of native konjac glucomannan 被引量:1
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作者 Long LI Hui RUAN +3 位作者 Liu-liu MA Wei WANG Ping ZHOU Guo-qing HE 《Journal of Zhejiang University-Science B(Biomedicine & Biotechnology)》 SCIE CAS CSCD 2009年第4期273-279,共7页
We investigated the higher structure of konjac glucomannan (KGM) in the amorphous state and solution using a laser particle size analyzer and a water activity meter. The results show that the thermodynamic structures ... We investigated the higher structure of konjac glucomannan (KGM) in the amorphous state and solution using a laser particle size analyzer and a water activity meter. The results show that the thermodynamic structures of native KGM were primarily composed of the lamella structure units, which involve both granular crystalline and amorphous regions, and that the connection zones of such units contained both loose and tight aggregation regions. The value of surface tension (σ) of native KGM, resting with the density of its hydroxyl groups' self-association, was an important parameter to analyze the higher structures of native KGM in the thermodynamic swelling model of native KGM. 展开更多
关键词 Swelling model Thermodynamic structure Konjac glucomannan (KGM) Higher structure
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Correspondence between Yang–Mills Condensate Dark Energy with Various Kinds of Scalar Field Models of Dark Energy
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作者 Pameli Saha Ujjal Debnath 《Communications in Theoretical Physics》 SCIE CAS CSCD 2016年第11期579-588,共10页
In this work, we study a new kind of dark energy (DE), which is named as "Yang-Mills condensate" (YMC). We study the stability and wde - w'de analysis of YMC DE model. Then we correspond it with quintessence, k... In this work, we study a new kind of dark energy (DE), which is named as "Yang-Mills condensate" (YMC). We study the stability and wde - w'de analysis of YMC DE model. Then we correspond it with quintessence, k- essence, tachyon, phantom, dilaton, DBI-essence and hessenee scalar field models of DE in FRW spacetime to reconstruct potentials as well as the dynamics for these scalar fields for describing the acceleration of the universe. We also analyze the models in graphically to interpret the nature of the scalar fields and corresponding potentials. 展开更多
关键词 dark energy scalar field models correspondence
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Research on the transverse mode competition in a Yb-doped 18-core photonic crystal fiber laser
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作者 王远 姚建铨 +3 位作者 郑一博 温午麒 陆颖 王鹏 《Optoelectronics Letters》 EI 2012年第6期426-429,共4页
A model based on propagation rate equations is built up for analyzing the multicore Iransverse mode gain distribution in an 18-core photonic crystal fiber (PCF) laser. The two kinds of feedback cavities are used for... A model based on propagation rate equations is built up for analyzing the multicore Iransverse mode gain distribution in an 18-core photonic crystal fiber (PCF) laser. The two kinds of feedback cavities are used for the fiber laser, which are the buttcontact mirror and the Talbot cavity. According to the model, the transverse mode competitions in different feedback cavities are simulated numerically. The results show that the Talbot cavity can improve in-phase supermode gain, while sunnress other sunerrnodes. 展开更多
关键词 Computer simulation Fiber lasers Photonic crystal fibers YTTERBIUM
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SOLITONS AND CONSERVATION LAWS IN NEUROSCIENCES
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作者 AN JAN BISWAS ABDUL H. KARA +2 位作者 MICHELLE SAVESCU ASHFAQUE H. BOKHARI F. D. ZAMAN 《International Journal of Biomathematics》 2013年第3期101-107,共7页
This paper obtains the 1-soliton solution by the ansatz method for the proposed model that governs the propagation of solitons through the neurons. This model is an improved one that describes the solitons in neurosci... This paper obtains the 1-soliton solution by the ansatz method for the proposed model that governs the propagation of solitons through the neurons. This model is an improved one that describes the solitons in neurosciences more accurately. The ansatz method is applied to obtain the 1-soliton solution to the model. The Lie symmetry analysis is subsequently applied to obtain the conservation laws for the model. 展开更多
关键词 SOLITONS INTEGRABILITY conservation laws neuroscience.
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