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《局方》消风散治疗脾虚湿盛风邪外犯型荨麻疹42例
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作者 苏德成 苏战豹 《中国中医药咨讯》 2009年第5期32-32,共1页
目的:观察《局方》消风散治疗脾虚湿盛风邪外犯型荨麻疹的临床疗效。方法:将82例中医辨证为脾虚湿盛风邪外犯型荨麻疹患者随机分为2组。治疗组42例采用《局方》消风散治疗,对照组40例采用口服西替利嗪片治疗。2组均以7天为1个疗程,... 目的:观察《局方》消风散治疗脾虚湿盛风邪外犯型荨麻疹的临床疗效。方法:将82例中医辨证为脾虚湿盛风邪外犯型荨麻疹患者随机分为2组。治疗组42例采用《局方》消风散治疗,对照组40例采用口服西替利嗪片治疗。2组均以7天为1个疗程,2个疗程后统计疗效。结果:治疗组总有效率为90.48%,对照组总有效率为70%,2组比较有显著性差异(P〈0.05)。结论:《局方》消风散治疗脾虚湿盛风邪外犯型荨麻疹疗效确切。 展开更多
关键词 方》消风 荨麻疹 中医药疗法
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局方至宝散中牛黄质量控制方法的研究 被引量:9
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作者 夏晶 王伟毅 +2 位作者 沙祎炜 王柯 季申 《中国卫生检验杂志》 CAS 2011年第8期1872-1874,1877,共4页
目的:建立控制局方至宝散中牛黄质量的分析方法,用于制剂中投料所用牛黄的品种及质量监控。方法:采用薄层检查法检测猪去氧胆酸成分;采用薄层扫描法对局方至宝散中牛黄的胆酸含量进行测定,展开剂为环己烷-乙酸乙酯-36%乙酸-甲醇(20∶25... 目的:建立控制局方至宝散中牛黄质量的分析方法,用于制剂中投料所用牛黄的品种及质量监控。方法:采用薄层检查法检测猪去氧胆酸成分;采用薄层扫描法对局方至宝散中牛黄的胆酸含量进行测定,展开剂为环己烷-乙酸乙酯-36%乙酸-甲醇(20∶25∶2∶3)上层溶液,展开2次;薄层板为硅胶G板,显色剂为10%硫酸乙醇溶液(V/V)1,05℃加热至斑点显色清晰;检测波长为460 nm;采用高效液相色谱法对局方至宝散中牛黄的胆红素含量进行测定,色谱柱为Kromasil-C18(150 mm×4.6 mm,5μm)柱,流动相为乙腈-1%冰乙酸溶液(95∶5,V/V),流速为1.0 ml/min,检测波长为450 nm。结果:薄层检查法中,猪去氧胆酸的最低检出量为0.04μg。薄层扫描法中,胆酸线性范围为25.1 mg/ml~502.0 mg/ml,相关系数为0.999,检出限为0.06μg;平均加标回收率为100.8%,RSD为1.64%。高效液相色谱法中,胆红素方法线性范围为1.22 mg/ml~61.0 mg/ml,相关系数为0.9999,检出限为0.002μg;平均加标回收率为99.0%,RSD为1.62%。结论:该法操作简便,结果准确可靠,应用性较广。 展开更多
关键词 牛黄 方至宝 薄层检查法 薄层扫描法 高效液相色谱法
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Ground-roll separation of seismic data based on morphological component analysis in twodimensional domain 被引量:2
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作者 徐小红 屈光中 +2 位作者 张洋 毕云云 汪金菊 《Applied Geophysics》 SCIE CSCD 2016年第1期116-126,220,共12页
Ground roll is an interference wave that severely degrades the signal-to-noise ratio of seismic data and affects its subsequent processing and interpretation.In this study,according to differences in morphological cha... Ground roll is an interference wave that severely degrades the signal-to-noise ratio of seismic data and affects its subsequent processing and interpretation.In this study,according to differences in morphological characteristics between ground roll and reflected waves,we use morphological component analysis based on two-dimensional dictionaries to separate ground roll and reflected waves.Because ground roll is characterized by lowfrequency,low-velocity,and dispersion,we select two-dimensional undecimated discrete wavelet transform as a sparse representation dictionary of ground roll.Because of a strong local correlation of the reflected wave,we select two-dimensional local discrete cosine transform as the sparse representation dictionary of reflected waves.A sparse representation model of seismic data is constructed based on a two-dimensional joint dictionary then a block coordinate relaxation algorithm is used to solve the model and decompose seismic record into reflected wave part and ground roll part.The good effects for the synthetic seismic data and application of real seismic data indicate that when using the model,strong-energy ground roll is considerably suppressed and the waveform of the reflected wave is effectively protected. 展开更多
关键词 Ground-roll suppression morphological component analysis sparse representation two-dimensional undecimated discrete wavelet transform two-dimensional local discrete cosine transform
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Self-diffusion Coefficient Model Based on Activation Energy and Free Volume
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作者 尹小勇 宋海华 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 北大核心 2006年第6期488-492,共5页
A new model for self-diffusion coefficients was proposed based oil both the concepts of molecular free volume and activation energy. The unknown parameters of this model were clearly defined and compared with the Chap... A new model for self-diffusion coefficients was proposed based oil both the concepts of molecular free volume and activation energy. The unknown parameters of this model were clearly defined and compared with the Chapman-Enskog model. At the same time a new method for calculating activation energy was devised and applied to the new model. In addition, the free volume was defined by implementing the generic van der Waals equation of state, the radial distribution function of which was obtained by using the Morsali- Goharshadi empirical formula. Under the same conditions, the new model was better than the original free volume model. 展开更多
关键词 Free volume Potential energy barrier Self-diffusion coefficient Pair correlation function
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Nonlocal Symmetries to Systems of Nonlinear Diffusion Equations 被引量:1
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作者 QU Chang-Zheng KANG Jing 《Communications in Theoretical Physics》 SCIE CAS CSCD 2008年第1期9-16,共8页
In this paper, we study potential symmetries to certain systems of nonlinear diffusion equations. Thosesystems have physical applications in soil science, mathematical biology, and invariant curve flows in R^3. Lie po... In this paper, we study potential symmetries to certain systems of nonlinear diffusion equations. Thosesystems have physical applications in soil science, mathematical biology, and invariant curve flows in R^3. Lie point symmetries of the potential system, which cannot be projected to vector fields of the given dependent and independent variables, yield potential symmetries. The class of the system that admits potential symmetries is expanded. 展开更多
关键词 symmetry group system of nonlinear diffusion equation nonlocal symmetry
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Localization of Solutions of a Nonlinear Diffusion Problem
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作者 周文书 魏晓丹 《Chinese Quarterly Journal of Mathematics》 CSCD 北大核心 2008年第1期103-108,共6页
This paper concerns with properties of solutions of a nonlinear diffusion problem in non-divergence form. By constructing proper test functions, it is proved that solutions of the problem possess the property of local... This paper concerns with properties of solutions of a nonlinear diffusion problem in non-divergence form. By constructing proper test functions, it is proved that solutions of the problem possess the property of localization. 展开更多
关键词 nonlinear diffusion problem non-divergence form LOCALIZATION
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Quasilinear Hyperbolic Conservation Laws with Relaxation
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作者 LIU Fa-gui ZHANG Yuan-zhang 《Chinese Quarterly Journal of Mathematics》 CSCD 北大核心 2007年第1期143-154,共12页
In this paper, we investigate the relaxation phenomenon for quasilinear hyperbolic conservation laws, and obtain global smooth solutions and the life span of classical solutions to its Cauchy problem. These results sh... In this paper, we investigate the relaxation phenomenon for quasilinear hyperbolic conservation laws, and obtain global smooth solutions and the life span of classical solutions to its Cauchy problem. These results shows that the relaxation admits the effects of dissipation. 展开更多
关键词 conservation laws RELAXATION DISSIPATION global classical solution life span
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Blow-up for a Class of Degenerate Reaction-diffusion Equation with Nonlocal Source 被引量:2
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作者 CUI Guo-zhong GAO Yah-ling GUO Cong-zhou 《Chinese Quarterly Journal of Mathematics》 CSCD 2010年第3期352-359,共8页
This paper deals with the properties of the solution to a class of nonlocal degenerate reaction-diffusion equation with nonlocal source,subject to the null Dirichlet boundary condition.We first give sufficient conditi... This paper deals with the properties of the solution to a class of nonlocal degenerate reaction-diffusion equation with nonlocal source,subject to the null Dirichlet boundary condition.We first give sufficient conditions for that the solution exists globally or blows up in the finite time.Then the blow-up time is also given.At last,we obtain a property differing from the local source which the blow-up set is the entire interval. 展开更多
关键词 degenerate reaction-diffusion equation nonlocal source global existence blowup time blow-up set
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An efficient algorithm for mining closed itemsets 被引量:1
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作者 刘君强 潘云鹤 《Journal of Zhejiang University Science》 CSCD 2004年第1期8-15,共8页
This paper presents a new efficient algorithm for mining frequent closed itemsets. It enumerates the closed set of frequent itemsets by using a novel compound frequent itemset tree that facilitates fast growth and eff... This paper presents a new efficient algorithm for mining frequent closed itemsets. It enumerates the closed set of frequent itemsets by using a novel compound frequent itemset tree that facilitates fast growth and efficient pruning of search space. It also employs a hybrid approach that adapts search strategies, representations of projected transaction subsets, and projecting methods to the characteristics of the dataset. Efficient local pruning, global subsumption checking, and fast hashing methods are detailed in this paper. The principle that balances the overheads of search space growth and pruning is also discussed. Extensive experimental evaluations on real world and artificial datasets showed that our algorithm outperforms CHARM by a factor of five and is one to three orders of magnitude more efficient than CLOSET and MAFIA. 展开更多
关键词 Knowledge discovery Data mining Frequent closed patterns Association rules
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Super long-range diffusion of carbon during proeutectoid ferrite transformation 被引量:2
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作者 ZHANG Suo-quan JIAO Si-hai +3 位作者 DING Jian-hua WAN Di LIU Zhen-yu WANG Guo-dong 《Journal of Central South University》 SCIE EI CAS CSCD 2019年第3期560-566,共7页
In order to explore the possible diffusion distance of carbon during proeutectoid ferrite transformation, a slow cooling test of low carbon steel was carried out under vacuum of the thermal simulator. The microstructu... In order to explore the possible diffusion distance of carbon during proeutectoid ferrite transformation, a slow cooling test of low carbon steel was carried out under vacuum of the thermal simulator. The microstructure and thermal expansion curve were discussed and the carbon concentration inside the sample was measured. The ferrite layer of about 450 μm thickness was obtained without pearlite on the surface of the sample in the microstructure. The thermal expansion curve shows that the ferrite layer without pearlite is formed during the local phase transformation, which is followed by the global transformation. The carbon concentration in the core of the sample (0.061%) is significantly higher than that of the bulk material (0.054%). All results show that carbon has long-range diffusion from the outer layer to the inner layer of the sample. The transformation is predominantly interface-controlled mode during local transformation, and the interface migration rate is about 2.25 μm/s. 展开更多
关键词 low carbon steel local transformation super long-rang diffusion interface-controlled mode
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An effective discrete artificial bee colony algorithm for flow shop scheduling problem with intermediate buffers 被引量:3
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作者 张素君 顾幸生 《Journal of Central South University》 SCIE EI CAS CSCD 2015年第9期3471-3484,共14页
An effective discrete artificial bee colony(DABC) algorithm is proposed for the flow shop scheduling problem with intermediate buffers(IBFSP) in order to minimize the maximum completion time(i.e makespan). The effecti... An effective discrete artificial bee colony(DABC) algorithm is proposed for the flow shop scheduling problem with intermediate buffers(IBFSP) in order to minimize the maximum completion time(i.e makespan). The effective combination of the insertion and swap operator is applied to producing neighborhood individual at the employed bee phase. The tournament selection is adopted to avoid falling into local optima, while, the optimized insert operator embeds in onlooker bee phase for further searching the neighborhood solution to enhance the local search ability of algorithm. The tournament selection with size 2 is again applied and a better selected solution will be performed destruction and construction of iterated greedy(IG) algorithm, and then the result replaces the worse one. Simulation results show that our algorithm has a better performance compared with the HDDE and CHS which were proposed recently. It provides the better known solutions for the makespan criterion to flow shop scheduling problem with limited buffers for the Car benchmark by Carlier and Rec benchmark by Reeves. The convergence curves show that the algorithm not only has faster convergence speed but also has better convergence value. 展开更多
关键词 discrete artificial bee colony algorithm flow shop scheduling problem with intermediate buffers destruction and construction tournament selection
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Cauchy Problem for the Nonlinear Double Dispersive Wave Equation
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作者 郭基风 李红 《Chinese Quarterly Journal of Mathematics》 CSCD 北大核心 2007年第3期415-425,共11页
This paper concerns with the Cauchy problem for the nonlinear double dispersive wave equation. By the priori estimates and the method in [9], It proves that the Cauchy problem admits a unique global classical solution... This paper concerns with the Cauchy problem for the nonlinear double dispersive wave equation. By the priori estimates and the method in [9], It proves that the Cauchy problem admits a unique global classical solution. And by the concave method, we give sufficient conditions on the blowup of the global solution for the Cauchy problem. 展开更多
关键词 Cauchy problem double dispersive wave equation global classical solution BLOWUP
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Critical Fujita Exponents for Localized Reaction Diffusion Systems
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作者 赵云 王术 张建平 《Chinese Quarterly Journal of Mathematics》 CSCD 1999年第2期102-107, ,共6页
In this paper, we prove the existence of cirtical Fujita exponents for a class of localized reaction diffusion systems.
关键词 localized reaction diffusion systems blow up global solutions cirtical Fujita exponents
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Influences of nonassociated flow rules on three-dimensional seismic stability of loaded slopes 被引量:3
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作者 N.GANJIAN F.ASKARI O.FARZANEH 《Journal of Central South University》 SCIE EI CAS 2010年第3期603-611,共9页
The influences of soil dilatancy angle on three-dimensional (3D) seismic stability of locally-loaded slopes in nonassociated flow rule materials were investigated using a new rotational collapse mechanism and quasi-... The influences of soil dilatancy angle on three-dimensional (3D) seismic stability of locally-loaded slopes in nonassociated flow rule materials were investigated using a new rotational collapse mechanism and quasi-static coefficient concept. Extended Bishop method and Boussinesq theorem were employed to establish the stress distribution along the rupture surfaces that are required to obtain the rate of internal energy dissipation for the nonassociated flow rule materials in rotational collapse mechanisms. Good agreement was observed by comparing the current results with those obtained using the translational or rotational mechanisms and numerical finite difference method. The results indicate that the seismic stability of slopes reduces by decreasing the dilatancy angle for nonassociated flow rule materials. The amount of the mentioned decrease is more significant in the case of mild slopes in frictional soils. A nearly infinite slope under local loading, whether its critical failure surface is 2D or 3D, not only depends on the magnitude of the external load, but also depends on the dilataney angle of soil and the coefficient of seismic load. 展开更多
关键词 3D slope stability failure analysis nonassociated flow rule
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An analytical model for local-nonequilibrium solute trapping during rapid solidification 被引量:2
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作者 S. L. SOBOLEV 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2012年第11期2749-2755,共7页
Updated version of local non-equilibrium diffusion model (LNDM) for rapid solidification of binary alloys was considered. The LNDM takes into account deviation from local equilibrium of solute concentration and solu... Updated version of local non-equilibrium diffusion model (LNDM) for rapid solidification of binary alloys was considered. The LNDM takes into account deviation from local equilibrium of solute concentration and solute flux fields in bulk liquid. The exact solutions for solute concentration and flux in bulk liquid were obtained using hyperbolic diffusion equations. The results show the transition from diffusion-limited to purely thermally controlled solidification with effective diffusion coefficient →0 and complete solute trapping KLNDM(v)→1 at v→vDb for any kind of solid-liquid interface kinetics. Critical parameter for diffusionless solidification and complete solute trapping is the diffusion speed in bulk liquid vDb. Different models for solute trapping at the interface with different interface kinetic approaches were considered. 展开更多
关键词 binary alloys solute trapping rapid solidification local-nonequilibrium diffusion hyperbolic diffusion equation solute concentration solute flux fields
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Detection of Partial Discharge in Power Transformers Using Rogowski Coil and Multiresolution Analysis 被引量:1
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作者 G.F.C. Veloso L.E. Borges da Silva +4 位作者 I. Noronha G. Lambert Torres J. Haddad R.R. Pereira Se UnAhn 《Journal of Energy and Power Engineering》 2010年第2期39-45,共7页
Partial discharge detection in power transformers is discussed using a new approach that exploit the broad band of the Rogowski coils and the potential of two signal processing tools: discrete wavelet transform and e... Partial discharge detection in power transformers is discussed using a new approach that exploit the broad band of the Rogowski coils and the potential of two signal processing tools: discrete wavelet transform and empirical mode decomposition. Detecting and analyzing incipient activities of partial discharge can provide useful information to diagnostics and prognostics about transformer insulation. So, partial discharge signals embedded in the electric current at ground conductor are measured using the Rogowski coil. These signals are submitted to noise suppression and the partial discharges waveforms are extracted through different ways: using discrete wavelet transform and using empirical mode decomposition. The comparison of these two methods show that the extraction with discrete wavelet transform results in a faster and simpler algorithm than the empirical mode decomposition. But this one produces more precise waveforms due its adaptive characteristic. 展开更多
关键词 Discrete wavelet transform empirical mode decomposition partial discharge power transformer Rogowski coil.
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New interpretation of experimental data on Si-As alloy solidification with planar interface 被引量:1
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作者 S.L.SOBOLEV 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2015年第8期2797-2806,共10页
An analytical model was developed to describe Si?As alloy solidification in the whole range of measured interface velocity. It is demonstrated that at low interface velocity, the solidification occurs in the initial ... An analytical model was developed to describe Si?As alloy solidification in the whole range of measured interface velocity. It is demonstrated that at low interface velocity, the solidification occurs in the initial transient regime. The model leads to good comparison with the experimental data taking both local nonequilibrium effects at high interface velocity and steady state effects at low interface velocity into account. The local nonequilibrium diffusion effects shrink the initial transient period and lead to diffusionless solidification at high interface velocity. 展开更多
关键词 alloy solidification initial transient local-nonequilibrium diffusion hyperbolic diffusion equation Si-As alloys diffusionless solidification complete solute trapping
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An Improved Hybrid Genetic Algorithm for Chemical Plant Layout Optimization with Novel Non-overlapping and Toxic Gas Dispersion Constraints 被引量:8
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作者 徐圆 王振宇 朱群雄 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2013年第4期412-419,共8页
New approaches for facility distribution in chemical plants are proposed including an improved non-overlapping constraint based on projection relationships of facilities and a novel toxic gas dispersion constraint. In... New approaches for facility distribution in chemical plants are proposed including an improved non-overlapping constraint based on projection relationships of facilities and a novel toxic gas dispersion constraint. In consideration of the large number of variables in the plant layout model, our new method can significantly reduce the number of variables with their own projection relationships. Also, as toxic gas dispersion is a usual incident in a chemical plant, a simple approach to describe the gas leakage is proposed, which can clearly represent the constraints of potential emission source and sitting facilities. For solving the plant layout model, an improved genetic algorithm (GA) based on infeasible solution fix technique is proposed, which improves the globe search ability of GA. The case study and experiment show that a better layout plan can be obtained with our method, and the safety factors such as gas dispersion and minimum distances can be well handled in the solution. 展开更多
关键词 plant layout non-overlapping constraints toxic gas dispersion genetic algorithm
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Incorporating the Built Environment Interactions into Spatial Pattern Models to Understand Urban Metabolism in Tokyo's Residential Area
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作者 Akiko Kokubun Eiji Hato 《Journal of Civil Engineering and Architecture》 2013年第7期854-866,共13页
In Tokyo, as residential areas exist in the urban areas and are composed of areas owned by individual land owners, basically spatial changes are brought by redevelopments of each sites conducted by individual circumst... In Tokyo, as residential areas exist in the urban areas and are composed of areas owned by individual land owners, basically spatial changes are brought by redevelopments of each sites conducted by individual circumstances and motivations. Continuous redevelopments and spatial changes can be found dispersedly in areas. Once the spatial change in a certain site occurred in an area as a building, it will be contained in the built environment of the residential area which is defined by residents, planners and designers who will take part in the following spatial changes. In Tokyo, public transportation facilities are well developed, and residents' daily life involves activities such as a slow walking and bicycle, etc. around the place of residence near the public transportation hubs, each living territories are formed in this kind of manner. Considering the maintenance of spatial value in residential areas while understanding transformation of visual local environment in residential areas which focuses on appearance of each spatial change in an area of street will be of significant importance. In this paper, the authors try to describe interactions of spatial changes in existing urban residential areas focusing on utility of players who might take part in the following spatial changes and the method of discrete choice model. 展开更多
关键词 Existing urban residential areas in Tokyo redevelopment of housing site modification interaction discrete choicemodel.
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Global Asymptotically Stable of a Generalized Discrete Ricker Competition System
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作者 Yoshihiro Hamaya 《Journal of Mathematics and System Science》 2013年第6期282-288,共7页
The purpose of this article is to investigate the sufficient conditions for the global asymptotic stability of one equilibrium point of a generalized Ricker competition system,……which appears as a model for dynamics... The purpose of this article is to investigate the sufficient conditions for the global asymptotic stability of one equilibrium point of a generalized Ricker competition system,……which appears as a model for dynamics with one extinct species, by applying the technique of average functions and the new principle of competitive exclusion. 展开更多
关键词 Generalized discrete ricker competition systems average functions new principle of competitive exclusion.
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