Micro-Macro Limit of a Nonlocal Generalized Aw-Rascle Type Model

Typically, political consumerism is portrayed in straightforward, unproblematic ways. This chapter discusses how and why political consumerism—and particularly boycotts—can be confusing and problematic. Theoretically it focuses on moral dilemmas within political consumerism and the key role of overriding moral claims in the motivations for and actions of political consumer causes. An ideal type model, constructed for analyzing unproblematic and problematic political consumerism, is applied to cases of more unproblematic political consumerism (e.g., the Nestlé, Nike, and South African boycotts) and more problematic political consumerism (e.g., the Disney boycott and the movement against Israeli settlements in the occupied Palestine territories). The chapter also addresses why other forms of political consumerism (buycotts and discursive actions) seem less vulnerable to moral dilemmas as well as the research challenges in studying more problematic cases of political consumerism.

Download Full-text

An attractive numerical algorithm for solving nonlinear Caputo–Fabrizio fractional Abel differential equation in a Hilbert space

Advances in Difference Equations ◽

10.1186/s13662-021-03428-3 ◽

2021 ◽

Vol 2021 (1) ◽

Author(s):

Mohammed Al-Smadi ◽

Nadir Djeddi ◽

Shaher Momani ◽

Shrideh Al-Omari ◽

Serkan Araci

Keyword(s):

Differential Equation ◽

Hilbert Space ◽

Reproducing Kernel ◽

Numerical Approach ◽

Accurate Solution ◽

Stability And Convergence ◽

Type Model ◽

Schmidt Orthogonalization ◽

And Performance ◽

Abel Differential Equation

AbstractOur aim in this paper is presenting an attractive numerical approach giving an accurate solution to the nonlinear fractional Abel differential equation based on a reproducing kernel algorithm with model endowed with a Caputo–Fabrizio fractional derivative. By means of such an approach, we utilize the Gram–Schmidt orthogonalization process to create an orthonormal set of bases that leads to an appropriate solution in the Hilbert space $\mathcal{H}^{2}[a,b]$ H 2 [ a , b ] . We investigate and discuss stability and convergence of the proposed method. The n-term series solution converges uniformly to the analytic solution. We present several numerical examples of potential interests to illustrate the reliability, efficacy, and performance of the method under the influence of the Caputo–Fabrizio derivative. The gained results have shown superiority of the reproducing kernel algorithm and its infinite accuracy with a least time and efforts in solving the fractional Abel-type model. Therefore, in this direction, the proposed algorithm is an alternative and systematic tool for analyzing the behavior of many nonlinear temporal fractional differential equations emerging in the fields of engineering, physics, and sciences.

Download Full-text

Optimal Control for a COVID-19 Model Accounting for Symptomatic and Asymptomatic

Computational and Mathematical Biophysics ◽

10.1515/cmb-2020-0109 ◽

2020 ◽

Vol 8 (1) ◽

pp. 168-179

Author(s):

Jead M. Macalisang ◽

Mark L. Caay ◽

Jayrold P. Arcede ◽

Randy L. Caga-anan

Keyword(s):

Optimal Control ◽

Control Theory ◽

Medical Care ◽

Optimal Control Theory ◽

Comparable Result ◽

Type Model ◽

Hospital Beds ◽

Transmission Reduction ◽

Bed Capacity ◽

The Government

AbstractBuilding on an SEIR-type model of COVID-19 where the infecteds are further divided into symptomatic and asymptomatic, a system incorporating the various possible interventions is formulated. Interventions, also referred to as controls, include transmission reduction (e.g., lockdown, social distancing, barrier gestures); testing/isolation on the exposed, symptomatic and asymptomatic compartments; and medical controls such as enhancing patients’ medical care and increasing bed capacity. By considering the government’s capacity, the best strategies for implementing the controls were obtained using optimal control theory. Results show that, if all the controls are to be used, the more able the government is, the more it should implement transmission reduction, testing, and enhancing patients’ medical care without increasing hospital beds. However, if the government finds it very difficult to implement the controls for economic reasons, the best approach is to increase the hospital beds. Moreover, among the testing/isolation controls, testing/isolation in the exposed compartment is the least needed when there is significant transmission reduction control. Surprisingly, when there is no transmission reduction control, testing/isolation in the exposed should be optimal. Testing/isolation in the exposed could seemingly replace the transmission reduction control to yield a comparable result to that when the transmission reduction control is being implemented.

Download Full-text

Revisiting the mechanism of β-O-4 bond cleavage during acidolysis of lignin VII: acidolyses of non-phenolic C6-C2-type model compounds using HBr, HCl and H2SO4, and a proposal on the characteristic action of Br− and Cl−

Journal of Wood Science ◽

10.1186/s10086-020-01928-6 ◽

2020 ◽

Vol 66 (1) ◽

Author(s):

Qiaoqiao Ye ◽

Tomoya Yokoyama

Keyword(s):

Model Compound ◽

Bond Cleavage ◽

Type Model ◽

Enol Ether ◽

Lignin Model Compound ◽

Benzyl Cation ◽

Acid Type ◽

Unstable Compound ◽

Lignin Model ◽

Acidolysis Reaction

AbstractA non-phenolic C6-C2-type lignin model compound with the β-O-4 bond, 2-(2-methoxyphenoxy)-1-(3,4-dimethoxyphenyl)ethanol (I), was acidolyzed in aqueous 82% 1,4-dioxane containing HBr, HCl, or H2SO4 with a concentration of 0.2 mol/L at 85 ℃ to examine the differences between these acidolyses. Compound I primarily converted to an enol ether compound, 1-(2-methoxyphenoxy)-2-(3,4-dimethoxyphenyl)ethene (II), via the benzyl cation followed by acidolytic β-O-4 bond cleavage regardless of the acid-type, although the disappearance rates of compound I were remarkably different (HBr > HCl >> H2SO4). Acidolyses of compound II using these acids under the same conditions showed a similar tendency, but the rate differences were much smaller than in the acidolyses of compound I. Acidolyses of the α-methyl-etherified derivative of compound I (I-α-OMe) using these acids under the same conditions suggested that the formation rates of the benzyl cation from compound I-α-OMe (also from compound I) are not largely different between the acidolyses using these acids, but those of compound II from the benzyl cation are remarkably different. Acidolysis of the α-bromo-substituting derivative of compound I (I-α-Br) using HBr under the same conditions showed a characteristic action of Br¯ in the acidolysis. Br¯ adds to the benzyl cation generated from compound I or I-α-OMe to afford unstable compound I-α-Br, resulting in acceleration of the formation of compound II and of the whole acidolysis reaction.

Download Full-text

Replication of left ventricular haemodynamics with a simple planar mitral valve model

Biomedical Engineering / Biomedizinische Technik ◽

10.1515/bmt-2019-0175 ◽

2020 ◽

Vol 0 (0) ◽

Author(s):

Anna Daub ◽

Jochen Kriegseis ◽

Bettina Frohnapfel

Keyword(s):

Mitral Valve ◽

Computational Models ◽

Vortex Formation ◽

Flow Characteristics ◽

Left Ventricular ◽

Computational Effort ◽

Type Model ◽

Diastolic Phase ◽

Valve Model ◽

Modelling Approach

AbstractTools for the numerical prediction of haemodynamics in multi-disciplinary integrated heart simulations have to be based on computational models that can be solved with low computational effort and still provide physiological flow characteristics. In this context the mitral valve model is important since it strongly influences the flow kinematics, especially during the diastolic phase. In contrast to a 3D valve, a vastly simplified valve model in form of a simple diode is known to be unable to reproduce the characteristic vortex formation and unable to promote a proper ventricular washout. In the present study, an adaptation of the widely used simplest modelling approach for the mitral valve is employed and compared to a physiologically inspired 3D valve within the same ventricular geometry. The adapted approach shows enhanced vortex formation and an improved ventricular washout in comparison to the diode type model. It further shows a high potential in reproducing the main flow characteristics and related particle residence times generated by a 3D valve.

Download Full-text