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Intraspecific floral colour variation in three Pedicularis species
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作者 Qiu-Yu Zhang Zhe Chen +1 位作者 Hang Sun Yang Niu 《Plant Diversity》 SCIE CAS CSCD 2024年第2期274-279,共6页
Flower constancy describes the phenomenon that pollinators tend to successively visit flowers of a single species during foraging,reducing reproductive interference in natural communities.The extent of flower constanc... Flower constancy describes the phenomenon that pollinators tend to successively visit flowers of a single species during foraging,reducing reproductive interference in natural communities.The extent of flower constancy is largely determined by the floral traits of co-flowering species.Both higher inter-specific and lower intraspecific differences of floral traits should contribute to a higher level of flower constancy.However,previous studies mainly focused on interspecific difference,and the intraspecific variation(consistency)of floral traits received much less attention.We hypothesise that selection may favour lower intraspecific floral trait variation in communities composed of multiple co-flowering congeners.We investigated the floral colour variation of three focal Pedicularis species that share pollinators in 19communities composed of either single or multiple Pedicularis species.Colour was quantified using image-based colour analysis as perceived by pollinators.We found that most of the intrapopulation floral colour variation was below the colour discrimination threshold of bumblebees,implying strongly constrained by the visual selection by pollinators.Contrary to the hypothesis,there is no significant difference in intraspecific floral colour variation between different community contexts.It may be due to the relatively large interspecific floral colour differences of most co-flowering species.The influence of community context on intraspecific variation may be reflected in floral traits other than colours. 展开更多
关键词 Flower constancy Floral colour variation Plantepollinator interactions Pollinator vision
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The Evaluation of the Dietary Habits Influence on the Microhardness of Gingiva-Coloured Composite and Acrylic Denture Base Materials
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作者 Hayriye Yasemin Yay Kuscu Ilhan Gun 《Advances in Nanoparticles》 CAS 2024年第3期79-95,共17页
Purpose: The study investigated the impact of dietary habits, specifically soda, milk kefir, water kefir, almond milk, and distilled water (control) consumption, on the microhardness of gingiva-coloured composite and ... Purpose: The study investigated the impact of dietary habits, specifically soda, milk kefir, water kefir, almond milk, and distilled water (control) consumption, on the microhardness of gingiva-coloured composite and acrylic denture bases. Methods: Materials included gingiva-coloured composite (Fusion Universal G1), acrylic (Imicryl), and subdivided Procryla group. Subgroups comprised 15 and 30-minute heat polymerized (Pro15, Pro30), and 1 wt% (Pro1Z) and 3 wt% (Pro3Z) zirconium added groups. Immersed in beverages for 1, 7, and 14 days, pH and microhardness were assessed. SEM examined random samples. Statistical analysis used repeated measures ANOVA, and post hoc tests (p Results: The gingiva-coloured composites displayed noteworthy time-associated microhardness changes (p 0.05). Despite variable pH levels in beverages, no substantial group interaction effects were observed (p > 0.05). Initial microhardness rankings shifted after a 14-day immersion. Conclusions: Gingiva-coloured composite exhibited the highest microhardness pre- and post-immersion, followed by Procryla30 and Imicryl groups. . 展开更多
关键词 Gingiva-coloured Composite ACRYLIC Denture Base Materials Hybrid Prosthesis MICROHARDNESS Beverages
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关于正整数有序分拆的一些恒等式和n-colour有序分拆的两个组合性质 被引量:3
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作者 郭育红 《纯粹数学与应用数学》 CSCD 2012年第5期590-594,613,共6页
研究了正整数的无序分拆与有序分拆的关系.给出了正整数的无序分拆与有序分拆的一些恒等式.并且利用菲波拉契数与正整数n分拆成不含分部量1的有序分拆数的关系给出了n-colour有序分拆的两个组合性质.
关键词 分拆恒等式 n—colour有序分拆 组合性质 菲波拉契数
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都用What colour吗?
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作者 姜经志 《中学生英语(初中版)》 2002年第21期12-12,共1页
英语中表示颜色的形容词很多,同学们学过的有black,red,yellow,blue,white,green,purple,brown,orange,grey等词。由于这些词在句中所作的成分不同,故提问的方式也不同。请看下面三道对划线部分提问的题:
关键词 “What colour 初中 英语 疑问词 颜色 形容词
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An Analysis of the Melancholy Colour in Robert Frost’s Poerty
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作者 杨绍芳 《科技信息》 2010年第12期I0132-I0133,共2页
Although a man stricken numerous times by pains and sufferings, Robert Frost had made the most excellent works in his lifetime. By carrying out a retrospection to Frost's rough life experiences and his times in li... Although a man stricken numerous times by pains and sufferings, Robert Frost had made the most excellent works in his lifetime. By carrying out a retrospection to Frost's rough life experiences and his times in light of their inseparable connection to and influence on his writing and analyzing the melancholy color presented in the main themes of "time"、"barrier"and "alienation and loneliness"which are concrete embodiments supporting the main element"melancholy", this thesis argues that Frost influenced his readers by inputting the element of melancholy into minds invisibly. With all the above efforts, the author of this thesis attempts to show a different side of Frost in a more specific and systematical way, and hopes it can help Frost readers understand him and read his poetry from a new angle. 展开更多
关键词 英语 诗歌 文学作品 文学评论
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Response of colour and hygroscopic properties of Scots pine wood to thermal treatment 被引量:7
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作者 Vasiliki Kamperidou Ioannis Barboutis Vasileios Vasileiou 《Journal of Forestry Research》 SCIE CAS CSCD 2013年第3期571-575,共5页
The effect of heat treatment on the surface colour and hygro- scopic properties of pine wood were investigated in this study. Boards of Scots pine wood (Pinus sylvestris L.) were subjected to thermal treatment at 20... The effect of heat treatment on the surface colour and hygro- scopic properties of pine wood were investigated in this study. Boards of Scots pine wood (Pinus sylvestris L.) were subjected to thermal treatment at 200℃, for 4, 6, and 8 h. The change of equilibrium moisture content and density values of the specimens in order to facilitate the understand- ing of the treated material behavior. The colour parameters L* a* and b*, used to depict the total colour change (dE) of wood surface, were shown to change proportionally to the treatment intensity. Moreover, swelling in the tangential and radial directions and absorption of the specimens ap- peared to be enhanced in great extent by the thermal treatment process. The mean value of swelling percentage in the tangential direction de- creased 10.26%, 17.22%, and 19.60% for specimens treated for 4, 6, and 8 h, respectively, referring to the final measurement after 72 h of immer- sion. In radial direction, mean value of swelling percentage decreased 19.56%, 32.75%, and 34.65% for treated for 4, 6 and 8 h, respectively, after 72 h immersion, which attests the decrease in swelling and im- provement in the hygroscopic behavior of Scots pine wood. 展开更多
关键词 colour Hygroscopic properties MODIFICATION Thermaltreatment Scots pine
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Colour and organic removal of biologically treated coffee curing wastewater by electrochemical oxidation method 被引量:7
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作者 Rajesh S. Bejankiwar K.S. Lokesh T.P. Halappa Gowda 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2003年第3期323-327,共5页
The treatment of biologically treated wastewater of coffee-curing industry by the electrochemical oxidation using steel anode was investigated. Bench-scale experiments were conducted for activated sludge process on ra... The treatment of biologically treated wastewater of coffee-curing industry by the electrochemical oxidation using steel anode was investigated. Bench-scale experiments were conducted for activated sludge process on raw wastewater and the treated effluents were further treated by electrochemical oxidation method for its colour and organic content removal. The efficiency of the process was determined in terms of removal percentage of COD, BOD and colour during the course of reaction. Several operating parameters like time, pH and current density were examined to ascertain their effects on the treatment efficiency. Steel anode was found to be effective for the COD and colour removal with anode efficiency of 0.118 kgCOD\5h -1\5A -1\5m -2 and energy consumption 20.61 kWh\5kg -1 of COD at pH 9. The decrease in pH from 9 to 3 found to increase the anode efficiency from 0.118 kgCOD\5h -1\5A -1\5m -2 to 0.144 kWh\5kg -1 of COD while decrease the energy consumption from 20.61 kWh\5kg -1 of COD to 12.86 kWh\5kg -1 of COD. The pH of 5 was considered an ideal from the present treatment process as it avoids the addition of chemicals for neutralization of treated effluents and also economical with respect to energy consumption. An empirical relation developed for relationship between applied current density and COD removal efficiency showed strong predictive capability with coefficient of determination of 96.5%. 展开更多
关键词 electrochemical oxidation coffee-curing wastewater steel anode COD colour removal
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与n-colour有序分拆相关的两个组合恒等式
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作者 郭育红 夏立华 《甘肃联合大学学报(自然科学版)》 2011年第2期1-3,共3页
给出了正整数ν分拆成m个分部量的n-colour有序分拆数的递推公式,并由这些递推关系得到了两个组合恒等式.
关键词 n-colour有序分拆 递推关系 组合恒等式
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Colour stabilities of three types of orthodontic clear aligners exposed to staining agents 被引量:5
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作者 Chen-Lu Liu Wen-Tian Sun +5 位作者 Wen Liao Wen-Xin Lu Qi-Wen Li Yunho Jeong Jun Liu Zhi-He Zhao 《International Journal of Oral Science》 SCIE CAS CSCD 2016年第4期246-253,共8页
The aim of this study was to evaluate and compare the colour stabilities of three types of orthodontic clear aligners exposed to staining agents in vitro. Sixty clear orthodontic aligners produced by three manufacture... The aim of this study was to evaluate and compare the colour stabilities of three types of orthodontic clear aligners exposed to staining agents in vitro. Sixty clear orthodontic aligners produced by three manufacturers (Invisalign, Angelalign, and Smartee) were immersed in three staining solutions (coffee, black tea, and red wine) and one control solution (distilled water). After 12-h and 7-day immersions, the aligners were washed in an ultrasonic cleaner and measured with a colourimeter. The colour changes (△E*) were calculated on the basis of the Commission Internationale de I'Eclairage L*a*b* colour system (CIE L*a*b*), and the results were then converted into National Bureau of Standards (NBS) units. Fourier transformation infrared (FT-IR) spectroscopy and scanning electron microscopy (SEM) were conducted to observe the molecular and morphologic alterations to the aligner surfaces, respectively. The three types of aligners exhibited slight colour changes after 12 h of staining, with the exception of the Invisalign aligners stained with coffee. The Invisalign aligners exhibited significantly higher AE* values (ranging from 0.30 to 27.81) than those of the Angelalign and Smartee aligners (AE* values ranging from 0.33 to 1.89 and 0.32 to 1.61, respectively, P〈O.05). IFT-IR analysis confirmed that the polymer-based structure of aligners did not exhibit significant chemical differences before and after the immersions. The SEM results revealed different surface alterations to the three types of aligner materials after the 7-day staining. The three types of aesthetic orthodontic appliances exhibited colour stability after the 12-h immersion, with the exception of the Invisalign aligners stained by coffee. The Invisalign aligners were more prone than the Angelalign and Smartee aligners to pigmentation. Aligner materials may be improved by considering aesthetic colour stability properties. 展开更多
关键词 AESTHETICS clear aligner clear aligner material colour stability orthodontic appliance
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正整数有序分拆的几个计数公式及n-colour有序分拆的一些新的组合性质
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作者 郭育红 《甘肃联合大学学报(自然科学版)》 2010年第1期25-28,共4页
本文首先给出了正整数分别恰含一个奇分部量和一个偶分部量的有序分拆数的计数公式.其次还利用正整数的"偶-奇"无序分拆给出了正整数的n-colour有序分拆的几个新的组合性质.
关键词 有序分拆 n-colour有序分拆 “偶-奇”无序分拆 组合性质
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The effect of dehydrogenase enzyme activity in glycolysis on the colour stability of mutton during postmortem storage 被引量:3
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作者 XIN Jian-zeng LI Zheng +4 位作者 LI Xin LI Meng WANG Ying YANG Fu-min ZHANG De-quan 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2017年第11期2646-2654,共9页
This study investigated the influence of activities of glyceraldehyde-3-phosphate dehydrogenase (GAPDH) and lactate dehydrogenase-B (LDH-B) on the colour stability of mutton. From 60 sheep (Bayannur mutton sheep... This study investigated the influence of activities of glyceraldehyde-3-phosphate dehydrogenase (GAPDH) and lactate dehydrogenase-B (LDH-B) on the colour stability of mutton. From 60 sheep (Bayannur mutton sheep), 15 Iongissimus dorsi (LD) muscles were selected on the basis of colour stability (R630/580 and a* value) during the storage and classified into three groups (5 for each group) as high colour stability (HCS), intermediate colour stability (ICS) and low colour stability (LCS). The activities of GAPDH and LDH-B, muscle colour attributes, nicotinamide adenine dinucleuotide (NADH) concen- tration and lactate concentration were measured. The samples in HCS had higher activities of GAPDH and LDH-B than the samples in the LCS, and the samples in the HCS group also possessed higher NADH and lower lactate concentration. The higher activity of dehydrogenase enzyme may result in higher NADH concentrations and colour stability in muscle tissue. The results suggest that the activity of GAPDH and LDH-B may also play a role in maintaining colour stability. 展开更多
关键词 MUTTON meat colour GAPDH LDH-B NADH
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Upper bound for the time derivative of entropy for a dynamical system driven by coloured cross-correlated white noises 被引量:2
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作者 谢文贤 徐伟 +1 位作者 蔡力 靳艳飞 《Chinese Physics B》 SCIE EI CAS CSCD 2005年第9期1766-1769,共4页
It is shown how the cross-correlation time and strength of coloured cross-correlated white noises can set an upper bound for the time derivative of entropy in a nonequilibrium system. The value of upper bound can be c... It is shown how the cross-correlation time and strength of coloured cross-correlated white noises can set an upper bound for the time derivative of entropy in a nonequilibrium system. The value of upper bound can be calculated directly based on the Schwartz inequality principle and the Fokker-Planck equation of the dynamical system driven by coloured cross-correlated white noises. The present calculations can be used to interpret the interplay of the dissipative constant and cross-correlation time and strength of coloured cross-correlated white noises on the upper bound. 展开更多
关键词 information entropy coloured cross-correlation Fokker-Planck equation
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Stochastic resonance driven by time-modulated correlated coloured noise sources in a single-mode laser 被引量:1
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作者 陈德彝 张莉 《Chinese Physics B》 SCIE EI CAS CSCD 2009年第5期1755-1760,共6页
This paper investigates the phenomenon of stochastic resonance in a single-mode laser driven by time-modulated correlated coloured noise sources. The power spectrum and signal-to-noise ratio R of the laser intensity a... This paper investigates the phenomenon of stochastic resonance in a single-mode laser driven by time-modulated correlated coloured noise sources. The power spectrum and signal-to-noise ratio R of the laser intensity are calculated by the linear approximation. The effects caused by noise self-correlation time τ1, τ2 and cross-correlated time τ3 for stochastic resonance are analysed in two ways: τ1, τ2 and τ3 are taken to be the independent variables and the parameters respectively. The effects of the gain coefficient F and loss coefficient K on the stochastic resonance are also discussed. It is found that besides the presence of the standard form and the broad sense of stochastic resonance, the number of extrema in the curve of R versus K is reduced with the increase of the gain coefficient Г. 展开更多
关键词 coloured noise coloured correlation time-periodic modulation signal-to-noise ratio
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Time dependence of entropy flux and entropy production for a dynamical system driven by noises with coloured cross-correlation 被引量:2
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作者 谢文贤 徐伟 蔡力 《Chinese Physics B》 SCIE EI CAS CSCD 2007年第1期42-46,共5页
This paper shows the Fokker-Planck equation of a dynamical system driven by coloured cross-correlated white noises in the absence and presence of a small external force. Based on the Fokker-Planck equation and the def... This paper shows the Fokker-Planck equation of a dynamical system driven by coloured cross-correlated white noises in the absence and presence of a small external force. Based on the Fokker-Planck equation and the definition of Shannon's information entropy, the time dependence of entropy flux and entropy production can be calculated. The present results can be used to explain the extremal behaviour of time dependence of entropy flux and entropy production in view of the dissipative parameter γ of the system, coloured cross-correlation time τ and coloured cross-correlation strength λ. 展开更多
关键词 information entropy entropy flux entropy production coloured cross-correlation Fokker-Planck equation
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Colour Removal from Aqueous Solutions of the Reactive Azo Dye Remazol Black B Using the Immobilised Cells (Shewanella Strain J18 143) –Cellulose-g.co-Monomer System 被引量:2
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作者 T. LI J. T. GUTHRIE 《Journal of Water Resource and Protection》 2010年第1期77-84,共8页
Consideration is given here to colour removal, carried out using immobilised biological cells, Shewanella strain J18 143. In order to provide greater control of an overall colour removal process and to give a basis fo... Consideration is given here to colour removal, carried out using immobilised biological cells, Shewanella strain J18 143. In order to provide greater control of an overall colour removal process and to give a basis for the effective recovery of the cell culture species, cell immobilisation has been established on chemically modified cellulose. The modification was achieved by chemically inducing the graft copolymerisation of methacrylic acid onto cotton fabric. The immobilised cells were able to decolorise the dye. The immobilisation methods, physical adsorption, “growing-in” and chemical coupling, were compared. Each of the methods was effective to some extent. However, the latter two immobilisation methods provided the greater effect in decoloration. Each of these immobilised systems is relatively simple to achieve, whether by adsorption, physical interlocking or covalent coupling. The graft copolymer is able to offer versatility in use. The decoloration was shown to be rapid under relatively simple processing conditions. Thus, compared with the established controls, complete decoloration of solutions of Remazol Black B was observed. The potential use of the graft copolymer substrate as support for a biochemical agent was confirmed. 展开更多
关键词 REACTIVE Azo DYES colour Removal Immobilisation Immobilised Cells
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ON f-EDGE COVER-COLOURING OF SIMPLE GRAPHS 被引量:1
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作者 宋慧敏 刘桂真 《Acta Mathematica Scientia》 SCIE CSCD 2005年第1期145-151,共7页
An f-edge cover-colouring of a graph G = (V, E) is an assignment of colours to the edges of G such that every colour appears at each vertex v ∈ V at least f(v) times. The maximum number of colours needed to f-edge co... An f-edge cover-colouring of a graph G = (V, E) is an assignment of colours to the edges of G such that every colour appears at each vertex v ∈ V at least f(v) times. The maximum number of colours needed to f-edge cover colour G is called the f-edge cover chromatic index of G, denoted by Xfc(G). This paper gives that min[d(v)-1/f(v)]≤xfc(G)≤ 展开更多
关键词 Edge colouring edge cover-colouring f-edge cover-colouring
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CLOTHING COLOUR PREFERENCES IN A HOSPITAL ENVIRONMENT IN HONG KONG: PART I - CHILD PATIENT'S PREFERENCES OF COLOUR ON NURSE UNIFORM 被引量:1
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作者 林倚妮 杨国荣 《Journal of China Textile University(English Edition)》 EI CAS 1997年第3期81-88,共8页
The aim of this study explored the importance of colour application on clothing and investigated whether there is a preference of colour on clothing among children under hospital environment. A modified colour associa... The aim of this study explored the importance of colour application on clothing and investigated whether there is a preference of colour on clothing among children under hospital environment. A modified colour associated test based on the Luster Color Test was used to carry out the survey. Fifty child patients aged four to sixteen were asked to look at two specially designed colour cards and to name their preferences and associations on each of the colour. 展开更多
关键词 hospital environment CHILD patients colour PREFERENCES NURSE uniform.
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Stochastic resonance in an asymmetric bistable system driven by coloured noises 被引量:1
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作者 杨建华 刘先斌 《Chinese Physics B》 SCIE EI CAS CSCD 2010年第5期92-97,共6页
The phenomenon of stochastic resonance is investigated in an asymmetric bistable system with coloured noises. The approximate Fokker Planck equation is derived based on the Novikov theorem and the Fox approach. By app... The phenomenon of stochastic resonance is investigated in an asymmetric bistable system with coloured noises. The approximate Fokker Planck equation is derived based on the Novikov theorem and the Fox approach. By applying the two-state theory, the expression of the signal-to-noise ratio is obtained in the adiabatic limit. The effects of the noise parameters on signal-to-ratio are discussed. It is found that the stochastic resonance phenomena appear in most cases and disappear in some special cases. 展开更多
关键词 stochastic resonance asymmetric bistable system coloured noises
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RESEARCH ON FACTORS AFFECTING THE COLOURATION OF RED GLASS-CERAMICS 被引量:1
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作者 赵前 程金树 +1 位作者 王怀德 袁坚 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 1996年第3期46-52,共7页
In this pater, effect of alkali, zinc oxide and colorants such as cadmiun sulfide and selenium powder on the colouration of the red glass-ceramic materials in the CaO-Al2O3-SiO2 system has been studied. The relevant l... In this pater, effect of alkali, zinc oxide and colorants such as cadmiun sulfide and selenium powder on the colouration of the red glass-ceramic materials in the CaO-Al2O3-SiO2 system has been studied. The relevant laws have been presented and analyzed. 展开更多
关键词 red glass-ceramics cadmium sulfide selenium powder colouration agent
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Formation and instability of spiral wave induced by Gaussian coloured noise 被引量:1
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作者 甘正宁 马军 +1 位作者 张国勇 陈勇 《Chinese Physics B》 SCIE EI CAS CSCD 2008年第11期4047-4055,共9页
In this paper, we studied the effect of Gaussian coloured noise on the formation and instability of spiral waves described by one class of modified FitzHugh Nagumo equation. It was found that Gaussian coloured noise p... In this paper, we studied the effect of Gaussian coloured noise on the formation and instability of spiral waves described by one class of modified FitzHugh Nagumo equation. It was found that Gaussian coloured noise plays a constructive role in the formation, transition and instability of spiral wave. Too weak or too strong noise may act against the formation of spiral waves. At a certain noise level, spiral wave is maintained in a medium, in which spiral wave cannot be observed in the absence of the noise. It is difficult to make a stable spiral wave into unstable state by Gaussian coloured noise, unless the noise level is very high. The parameter regions of Gaussian coloured noise for spiral forming and spiral instability were given and discussed with numerical simulations. 展开更多
关键词 spiral wave FitzHugh-Nagumo model Gaussian coloured noise
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