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Optimal Control Analysis of a Cholera Epidemic Model 霍乱流行模型的最优控制分析
Pub Date : 2019-03-21 DOI: 10.1142/S1793048019500024
P. Panja
In this paper, a cholera disease transmission mathematical model has been developed. According to the transmission mechanism of cholera disease, total human population has been classified into four subpopulations such as (i) Susceptible human, (ii) Exposed human, (iii) Infected human and (iv) Recovered human. Also, the total bacterial population has been classified into two subpopulations such as (i) Vibrio Cholerae that grows in the infected human intestine and (ii) Vibrio Cholerae in the environment. It is assumed that the cholera disease can be transmitted in a human population through the consumption of contaminated food and water by Vibrio Cholerae bacterium present in the environment. Also, it is assumed that Vibrio Cholerae bacterium is spread in the environment through the vomiting and feces of infected humans. Positivity and boundedness of solutions of our proposed system have been investigated. Equilibrium points and the basic reproduction number [Formula: see text] are evaluated. Local stability conditions of disease-free and endemic equilibrium points have been discussed. A sensitivity analysis has been carried out on the basic reproduction number [Formula: see text]. To eradicate cholera disease from the human population, an optimal control problem has been formulated and solved with the help of Pontryagin’s maximum principle. Here treatment, vaccination and awareness programs have been considered as control parameters to reduce the number of infected humans from cholera disease. Finally, the optimal control and the cost-effectiveness analysis of our proposed model have been performed numerically.
本文建立了霍乱传播的数学模型。根据霍乱疾病的传播机制,将总人口分为四个亚群,如:(i)易感人群,(ii)暴露人群,(iii)受感染人群和(iv)康复人群。此外,总的细菌种群已被划分为两个亚群,如(i)在受感染的人肠道内生长的霍乱弧菌和(ii)环境中的霍乱弧菌。据推测,霍乱可通过食用环境中存在的霍乱弧菌污染的食物和水在人群中传播。此外,据推测,霍乱弧菌是通过被感染者的呕吐和粪便在环境中传播的。研究了系统解的正性和有界性。求出平衡点和基本再现数[公式:见文]。讨论了无病平衡点和地方病平衡点的局部稳定条件。对基本再现数进行了敏感性分析[公式:见文]。为了从人群中根除霍乱,我们提出了一个最优控制问题,并利用庞特里亚金的极大值原理进行了求解。在这里,治疗、疫苗接种和意识规划被认为是减少霍乱感染人数的控制参数。最后,对所提出的模型进行了最优控制和成本效益分析。
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引用次数: 17
Comment On the Connection Between Planets, Dark Matter and Cancer, by Hector Socas-Navarro (arXiv:1812.02482 [physics.med-ph]) 《行星、暗物质和巨蟹座之间的联系》,作者:Hector Socas-Navarro (arXiv:1812.02482 [physical .med-ph])
Pub Date : 2018-12-19 DOI: 10.1142/S1793048019200029
K. Zioutas, Edward Valachovic, M. Maroudas
In arXiv:1812.02482 Socas-Navarro (SN) provided multiple confirmation of the claimed ~88 days melanoma periodicity [4] (which remarkably coincides with the orbital period of Mercury). This greatly strengthens the observation by Zioutas & Valachovic (ZV). Here we comment on the work by SN, because it objects the interpretation of the observation by ZV. Notice that SN objection is based on serious assumptions, which were explicitly excluded by ZV. Further, the conclusion made with a sub-set of data (4%) is statistically not significant to dispute ZV. On the contrary, since the same periodicity appears also in other 8 major cancer types, we consider it as a global oscillatory behaviour of cancer. At this stage, such a rather ubiquitous cancer periodicity makes any discussion of a small subset of data at least secondarily. Further, we show here that the ~88 days Melanoma periodicity is not related to solar activity. Planetary lensing of streaming low speed invisible massive particles remains the only viable explanation, as it has been introduced previously with a number of physics observations [4]. We also show that planetary lensing of low speed particles cannot be considered in isolation, because of the dominating Sun’s gravity, at least for the inner planets. Interestingly, gravitational lensing / deflection favours low speed particles. In a recent paper [1], H. Socas-Navarro (SN) has re-evaluated part of the work “Planetary Dependence of Melanoma” by K. Zioutas and E. Valachovic (ZV) [2], using even 8 more datasets. Here we comment on the work by SN, starting with two, in our opinion, positive aspects: 1) a) SN derives a periodicity of 87.6 days (4.17/year), confirming the value of (87.4±0.76) days as it was observed for the first time by ZV in ref. [2]. Interestingly, this periodicity appears also in all 8 major cancer categories, which have been Fourier analysed by SN. Obviously, this is a diversified confirmation, which strengthens greatly the initial observation by ZV. b) Figure 2 of the work by SN [1] confirms previous observation of the 11 years oscillation of melanoma [3]. 2) SN makes an extensive introduction to dark matter and WIMPs, arriving to conclusions objecting the work by ZV, since “it is incompatible with the current WIMP paradigm” [1]. We wish to stress here that the physics part of the work by ZV is based on ref.[4]; SN has apparently overlooked this important reference, since it is clarified there already in the introduction [4]: “...we refer to generic dark candidate constituents as “invisible massive matter”, in order to distinguish them from ordinary dark matter.” In addition, the words ‘dark matter’ and ‘WIMPs’ are not mentioned at all by ZV, (see ref.[2]). In other words, the conclusions made by SN are based just on dark matter and WIMPs, which are excluded by ZV (and in ref. [4] too); i.e., the objections by SN are thus based on assumptions considered as inapplicable [2,4]. 3) Melanoma and race: SN uses throughout his wo
在arXiv:1812.02482中,Socas-Navarro (SN)多次证实了黑色素瘤周期约为88天(与水星的轨道周期显著吻合)。这大大加强了Zioutas和Valachovic (ZV)的观察。这里我们对SN的工作进行评论,因为它反对ZV对观测结果的解释。请注意,SN异议是基于严肃的假设,而ZV明确排除了这些假设。此外,使用子集数据(4%)得出的结论对争议ZV没有统计学意义。相反,由于同样的周期性也出现在其他8种主要癌症类型中,我们认为它是癌症的全球振荡行为。在这个阶段,这种相当普遍的癌症周期性使得对一小部分数据的讨论至少是次要的。此外,我们在这里表明,~88天的黑色素瘤周期与太阳活动无关。行星透镜效应的低速不可见的大质量粒子流仍然是唯一可行的解释,因为它已经被引入了之前的一些物理观测[4]。我们还表明,低速粒子的行星透镜效应不能孤立地考虑,因为太阳的引力占主导地位,至少对内行星来说是这样。有趣的是,引力透镜/偏转倾向于低速粒子。在最近的一篇论文[1]中,H. Socas-Navarro (SN)重新评估了K. Zioutas和E. Valachovic (ZV)的部分“黑色素瘤的行星依赖性”研究,使用了8个以上的数据集。在这里,我们对SN的工作进行了评价,我们认为从两个积极的方面开始:1)a) SN得出的周期为87.6天(4.17/年),证实了ZV在参考文献[2]中首次观测到的(87.4±0.76)天的值。有趣的是,这种周期性也出现在SN进行傅里叶分析的所有8种主要癌症类别中。显然,这是一个多元化的证实,大大加强了ZV的初步观察。b) SN[1]的工作图2证实了先前对黑素瘤[3]11年振荡的观察。2) SN对暗物质和WIMP进行了广泛的介绍,得出了反对ZV工作的结论,因为“它与当前的WIMP范式不兼容”[1]。我们希望在这里强调,ZV工作的物理部分是基于ref.[4];SN显然忽略了这个重要的参考,因为它已经在介绍[4]中得到了澄清:“……我们把一般的暗物质候选成分称为“看不见的大质量物质”,以便将它们与普通暗物质区分开来。此外,ZV根本没有提到“暗物质”和“wimp”这两个词(参见参考文献[2])。换句话说,SN得出的结论仅仅是基于暗物质和wimp,它们被ZV(以及ref.[4])排除在外;也就是说,SN的反对意见基于被认为不适用的假设[2,4]。3)黑色素瘤和种族:SN在他的工作中自始至终使用WIMP范式来得出结论,即非裔美国人不能选择性地对暗物质免疫。首先,我们重申wimp和暗物质不在ZV的考虑范围之内。其次,美国疾病控制中心的网页[5]只是说明了没有种族对黑色素瘤免疫,所有年龄、种族和性别的人都是如此,这些人受到的影响并不总是平等的。更具体地说,非裔美国人的黑色素瘤发病率占总发病率的4%。因此,SN关于非裔美国人应该对暗物质免疫的结论并不适用。因为,如果我们用ZV所提倡的“看不见的大质量暗物质”来代替,如此小的速率可能会阻止隐藏的信号超越噪音。例如,即使是基于总人口的10 σ信号,对于非裔美国人的统计数据来说,也将处于~2 σ水平,也就是说,目前无法得出结论。事实上,由于同样的周期性也出现在其他8种主要癌症类型中,这种相当普遍的癌症周期性使得对一小部分数据的讨论至少是次要的。4)关于SN的其他反对意见(第3.1-3.4节):a)为了实现空间中公认缺失的合适几何场景,我们建议首先研究未被注意到的ref.[4]。事实上,参考文献[6]中的图2和参考文献[7]中的图2a)用它们的几个轨迹样本说明了慢速粒子的引力透镜是如何在由太阳主导的太阳系中发生的。显然,(内)行星对慢速粒子的整体引力聚焦性能也有影响(参见参考文献[8])。在缓慢的不可见的大质量粒子的情况下,我们有理由期望在行星轨道周期下游的聚焦流物质发生调制,这与ZV的观测结果相吻合。 对于慢速粒子,SN给出的行星引力透镜发生的精确对准流是强松弛的;随着速度v的减小,爱因斯坦环和偏转角分别以1/v和1/v的速度增大(参见ref.[9])。参考文献[6,7]给出的轨迹表明了这一点。此外,一个由慢速粒子组成的行星引力焦点,在理想情况下可以使通量增强多达10倍,而太阳的相应增强可能要大几个数量级。因此,行星引力透镜效应不能从太阳中孤立出来。b)关于罕见的双行星排列,由SN产生的流,适用于快流物质(速度大于~0.01c)。然而,对于缓慢的不可见的大质量粒子(速度低于~300 1000公里/秒),行星的引力影响必须与太阳的主导引力联系起来。上述注意事项(4.a)和参考文献[6,7]中的两幅图2都说明了实际情况。此外,还观测到行星与动态地球大气[4]的相关性,即其电离度。这是行星撞击地球的独立标志。c)诊断延迟和周期性:ZV已经解决了摘要末尾和参考文献[2]正文的延迟问题。我们注意到,在黑色素瘤发病和诊断之间,只有超过3个月的完全平坦随机延迟分布才能抑制观察到的短周期性的出现。毕竟,它的振幅意味着一小部分(~少数%)的黑色素瘤具有短潜伏期,这是合理的存在。因此,ZV得出的结论是,观测到的87.4天周期在较短的潜伏期内自行指向。有趣的是,SN对这种周期性的(多次)证实非常令人鼓舞,并加强了这种新方法在医学上的前景。正如SN所指出的那样,来自南半球的调查当然是有趣的,同时寻找可能的纬度依赖性,这对于识别假设的不可见流非常重要。据我们所知,对于观察到的黑色素瘤对行星的依赖,除了从黑暗区域“流不可见的大质量物质”的驱动思想之外,没有其他的解释,ZV紧随其后。更重要的是,这种振荡行为似乎在SN分析的所有傅立叶癌症类型中普遍存在,这是非常受欢迎和鼓舞的。ZV“只”关注黑色素瘤,因为在2010年之前观察到11年的周期。正如早些时候所证明的那样,这指向了行星之间可能存在的相关性,这种相关性最终被发现了。5)太阳活动:图1 (A)显示了黑色素瘤月发病率的傅立叶光谱(参考文献[2]中的图7c),以及1973-2010年(38年)同一时间间隔10.7 cm (F10.7)的太阳线的相应傅立叶光谱。请注意,F10.7被广泛认为是太阳活动的代表。两个光谱之间的比较(图1)排除了观察到的黑色素瘤周期(87.4±0.76)天在其起源有已知的太阳活动!然而,在图1 (B)中,计算的F10.7原始日值的傅立叶谱提供了各种其他谱线,但没有88天或365天的谱线。这是一个有趣的观察。因为当我们计算F10.7 (~2.8 GHz)太阳线连续88天和365天的日强度值之和(图2)时,两个光谱都显示出丰富的结构。然而,傅里叶分析并没有显示出88天或365天的峰值,这表明了傅里叶分析在这种情况下的局限性。同时,如图2所示的两幅光谱的光谱丰富度显示了这种简化光谱分析的优势。事实上,参考文献[2]中已经包含了几个这样的光谱。
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引用次数: 3
On the Connection between Planets, Dark Matter and Cancer: Comment on “Planetary Dependence of Melanoma” 论行星、暗物质与癌症的联系——评“黑色素瘤的行星依赖性”
Pub Date : 2018-12-06 DOI: 10.1142/S1793048019200017
H. Socas-Navarro
In a recent paper, Zioutas and Valachovic (2018) claim that dark matter is responsible for a significant fraction of the melanoma skin cancer. This conclusion is drawn from their observation of a significant correlation between skin melanoma incidence in the US and the inner planets positions (especially those of Mercury and Earth). Here, I present a number of objections to their interpretation. Some (but not all) of the counterarguments are based on the analysis of a larger dataset from the same source, considering more cancer types and separating by patient attributes, such as race. One of the counterarguments is that if the melanoma fluctuations with periods similar to planetary orbits were produced by dark matter density enhancements on Earth, then we would have to conclude that the black population is somehow immune to dark matter, a conclusion that seems incompatible with the current Weakly-Interacting Massive Particles (WIMP) paradigm. Interestingly, some periodicities are present in the data, including the ones reported by Zioutas and Valachovic, but I argue that they must have a societal rather than astronomical origin.
在最近的一篇论文中,Zioutas和Valachovic(2018)声称暗物质是癌症黑色素瘤皮肤的重要原因。这一结论是从他们对美国皮肤黑色素瘤发病率与内行星位置(尤其是水星和地球的位置)之间的显著相关性的观察中得出的。在这里,我对他们的解释提出一些反对意见。一些(但不是全部)反驳是基于对来自同一来源的更大数据集的分析,考虑了更多的癌症类型,并按患者属性(如种族)进行区分。其中一个反驳意见是,如果黑色素瘤周期与行星轨道相似的波动是由地球上暗物质密度增强引起的,那么我们就不得不得出结论,黑人群体在某种程度上对暗物质免疫,这一结论似乎与当前的弱相互作用大质量粒子(WIMP)范式不兼容。有趣的是,数据中存在一些周期性,包括Zioutas和Valachovic报告的周期性,但我认为它们一定有社会原因,而不是天文原因。
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引用次数: 3
Author Index Volume 13 (2018) 作者索引第13卷(2018年)
Pub Date : 2018-12-01 DOI: 10.1142/s1793048018990011
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引用次数: 0
Fuzzy Parameter Based Mathematical Model on Forest Biomass 基于模糊参数的森林生物量数学模型
Pub Date : 2018-12-01 DOI: 10.1142/S1793048018500108
P. Panja
In this paper, a fuzzy mathematical model has been developed by considering forest biomass, human population and technological effort for the conservation of forest biomass as separate compartments. We have assumed that the forest biomass and human population grows logistically. We have considered that forest biomass decreases due to industrialization, food, shelter, etc., for humans. For the conservation of forest biomass, some modern technological efforts have been used in this model. Also, time delay of use of modern technological effort for the conservation of forest biomass has been considered on forest biomass. According to the assumptions, a fuzzy mathematical model on forest biomass is formulated. Next we have determined different possible equilibrium points. Also, the stability of our proposed system around these equilibrium points has been discussed. Finally, some numerical simulation results have been presented for better understanding of our proposed mathematical model.
本文将森林生物量、人口和保护森林生物量的技术努力视为单独的隔间,建立了一个模糊数学模型。我们假设森林生物量和人口是按逻辑增长的。我们认为,由于工业化、人类的食物、住所等原因,森林生物量减少。为了保护森林生物量,在这一模式中使用了一些现代技术。此外,还考虑了在森林生物量方面延迟使用现代技术来保护森林生物量。根据这些假设,建立了森林生物量的模糊数学模型。接下来,我们确定了不同的可能平衡点。此外,还讨论了我们提出的系统在这些平衡点附近的稳定性。最后,给出了一些数值模拟结果,以更好地理解我们提出的数学模型。
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引用次数: 6
Modern Biophysical Approaches to Study Protein–Ligand Interactions 研究蛋白质-配体相互作用的现代生物物理方法
Pub Date : 2018-12-01 DOI: 10.1142/S1793048018300013
P. Biswas
Protein–ligand interactions act as a pivot to the understanding of most of the biological interactions. The study of interactions between proteins and cellular molecules has led to the establishment and identification of various important pathways that control biological systems. Investigators working in different fields of biological sciences have an intrinsic interest in this field and complement their findings by the application of different biophysical approaches and tools to quantify protein–ligand interactions that include protein–small molecules, protein–DNA, protein–RNA, protein–protein both in vitro and in vivo. In this paper, the various biophysical techniques that can be employed to study such interactions will be discussed. In addition to native gel electrophoresis and fluorescence-based methods, more details will be discussed, on the broad range of modern day biophysical tools such as Circular Dichroism, Fourier Transform Infrared (FTIR) Spectroscopy, Isothermal Titration Calorimetry, Analytical Ultracentrifugation, Surface Plasmon Resonance, Fluorescence Correlation Spectroscopy, Differential Scanning Fluorimetry, Nuclear Magnetic Resonance, Mass Spectroscopy, Single Molecule Spectroscopy, Dual Polarization Interferometry, Micro Scale Thermophoresis and Electro–switchable Biosensors that can be used to study the different aspects of protein–ligand interactions.
蛋白质-配体相互作用是理解大多数生物相互作用的关键。蛋白质和细胞分子之间相互作用的研究导致了控制生物系统的各种重要途径的建立和鉴定。在生物科学不同领域工作的研究人员对这一领域有着内在的兴趣,并通过应用不同的生物物理方法和工具来量化蛋白质与配体的相互作用,包括蛋白质与小分子、蛋白质与dna、蛋白质与rna、蛋白质与蛋白质在体外和体内的相互作用来补充他们的发现。在本文中,将讨论可用于研究这种相互作用的各种生物物理技术。除了天然凝胶电泳和基于荧光的方法,更多的细节将被讨论,在广泛的现代生物物理工具,如圆二色,傅里叶变换红外(FTIR)光谱,等温滴定量热法,分析超离心,表面等离子体共振,荧光相关光谱,差示扫描荧光法,核磁共振,质谱,单分子光谱,双偏振干涉法,微尺度热泳术和电开关生物传感器,可用于研究蛋白质-配体相互作用的不同方面。
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引用次数: 1
Effects of Fear and Additional Food in a Delayed Predator–Prey Model 延迟捕食者-被捕食模型中恐惧和额外食物的影响
Pub Date : 2018-12-01 DOI: 10.1142/S1793048018500091
Sudeshna Mondal, A. Maiti, G. Samanta
A field observation on a terrestrial vertebrate has shown that the fear of predators can affect the behavior of prey populations and it can greatly reduce their reproduction. On the other hand, it has been observed that providing additional food to the predator decreases the predatory attack rate and increases the growth rate of the predator. In this paper, we have investigated the dynamical behavior of a predator–prey model incorporating both the effects of fear and additional food. Positivity, uniform boundedness and extinction criteria of the system are studied. Equilibrium points and their stability behaviors are also discussed here. Existence of a Hopf-bifurcation is established by considering the level of fear as bifurcation parameter. The effect of time-delay is discussed, where the delay may be considered as gestation time of the predator. Numerical simulations are performed using MATLAB to verify our analytical findings.
对陆生脊椎动物的实地观察表明,对捕食者的恐惧会影响猎物种群的行为,并会大大减少它们的繁殖。另一方面,已经观察到,向捕食者提供额外的食物会降低捕食者的攻击率,并增加捕食者的生长速度。在这篇论文中,我们研究了捕食者-猎物模型的动力学行为,该模型同时考虑了恐惧和额外食物的影响。研究了系统的正性、一致有界性和消光准则。本文还讨论了平衡点及其稳定行为。将恐惧程度作为分岔参数,建立了Hopf分岔的存在性。讨论了时滞的影响,其中时滞可以被视为捕食者的妊娠时间。使用MATLAB进行了数值模拟,以验证我们的分析结果。
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引用次数: 52
A Size-Dependent Multiple-Loop Negative Feedback System Describes Biological Segment Formation Based on the Clock and Wavefront Mechanism 基于时钟和波前机制的描述生物节段形成的尺寸相关多环负反馈系统
Pub Date : 2018-12-01 DOI: 10.1142/S1793048018500121
Yusuke Shibasaki, C. Yoshida-Noro, Minoru Saito
We proposed a new mathematical model for biological segment formation based on the clock and wavefront mechanism suggested in 1970s. Here, we chose an invertebrate, Enchytraeus japonensis, as a model animal and adopted multiple-loop negative feedback system based on its physiological features. We numerically showed the segment number of the model animal is autopoietically controlled by a size-dependent function. Additionally, we discussed two cases of the irregular oscillations by applying the biological conditions for abnormal development. The present model showed robustness under local noise perturbations like many other biological oscillators and qualitatively described unique development of the model animal. As a result, we suggested that a global interaction of chemical signals in the body can also drive “segmentation clock”.
基于20世纪70年代提出的时钟和波前机制,我们提出了一种新的生物节段形成数学模型。在这里,我们选择了一种无脊椎动物日本卷尾虫(Enchytraeus japonensis)作为模型动物,并根据其生理特征采用了多回路负反馈系统。我们用数字表明,模型动物的节段数是由一个大小依赖函数自动控制的。此外,我们通过应用异常发育的生物学条件讨论了两种不规则振荡的情况。与许多其他生物振荡器一样,本模型在局部噪声扰动下表现出稳健性,并定性描述了模型动物的独特发育。因此,我们提出,体内化学信号的全局相互作用也可以驱动“分割时钟”。
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引用次数: 0
Modeling and Analysis of an Ecological System Incorporating Infection and Prey Refuge 一个包含感染和猎物避难的生态系统的建模与分析
Pub Date : 2018-12-01 DOI: 10.1142/S179304801850011X
Soovoojeet Jana, Samadyuti Haldar, D. Das, S. Nandi, T. K. Kar
This paper describes a prey–predator type ecological model with infection in the prey populations. We also consider here a nonlinear functional response for disease transmission and a constant amount of refuge for the sound prey populations. The dynamical behavior of the mathematical model is described from the point of view of stability and bifurcation. A geometric method is also applied to establish the global asymptotic stability at the co-existence equilibrium point. Some computer simulation works have been presented to illustrate the theoretical results.
本文描述了一个在猎物种群中具有感染的猎物-捕食者型生态模型。在这里,我们还考虑了疾病传播的非线性功能反应和健全猎物种群的恒定庇护量。从稳定性和分岔的角度描述了数学模型的动力学行为。还应用几何方法建立了共存平衡点的全局渐近稳定性。为了说明理论结果,已经给出了一些计算机模拟工作。
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引用次数: 1
An Imprecise Eco-Epidemic Model with Pesticide in Relevance to Agricultural Pest Control 与农业病虫害防治相关的含农药的不精确生态流行病模型
Pub Date : 2018-09-01 DOI: 10.1142/S1793048018500066
Anjana P. Das, M. Pal
In this paper, we have proposed and analyzed an agricultural pest control system. For this purpose, an eco-epidemiological type predator–prey model has been proposed with the consideration of a sound predator population and two classes of pest populations namely susceptible pest and infected pest. Further to consider uncertainty, we modify our model and transform it into a fuzzy system with incorporation of imprecise parameters. The dynamical behavior of the proposed model has been investigated by examining the existence and stability criteria of all feasible equilibria. An optimal control problem is formed by considering the pesticide control as the control parameter and then the problem is solved both theoretically and numerically with the help of some computer simulation works.
本文提出并分析了一种农业害虫防治系统。为此,提出了一个生态流行病学类型的捕食者-猎物模型,该模型考虑了健全的捕食者种群和两类害虫种群,即易感害虫和感染害虫。为了进一步考虑不确定性,我们对模型进行了修正,将其转化为包含不精确参数的模糊系统。通过检验所有可行平衡点的存在性和稳定性准则,研究了该模型的动力学行为。以农药控制为控制参数,形成了一个最优控制问题,并结合计算机仿真工作,从理论上和数值上对该问题进行了求解。
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引用次数: 1
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Biophysical reviews and letters
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