Body Of Theory Research Articles

Time decay for several porous thermoviscoelastic systems of Moore–Gibson–Thompson type

In this paper, we consider several problems arising in the theory of thermoelastic bodies with voids. Four particular cases are considered depending on the choice of the constitutive tensors, assuming different dissipation mechanisms determined by Moore–Gibson–Thompson-type viscosity. For all of them, the existence and uniqueness of solutions are shown by using semigroup arguments. The energy decay of the solutions is also analyzed for each case.

Expectations, concave transforms, chow weights and Roth’s theorem for varieties

We present a new perspective, which is at the intersection of K-stability and Diophantine arithmetic geometry. It builds on work of Boucksom and Chen (Compos Math 147(4):1205–1229, 2011), Boucksom et al. (Math Ann 361(3–4):811–834, 2015), Boucksom et al. (Ann Inst Fourier (Grenoble) 67(2):743–841, 2017), Codogni and Patakfalvi (Invent Math 223(3):811–894, 2021), Fujita (Amer J Math 140(2):391–414, 2018), Fujita (J reine angew Math 751:309–338, 2019), Li (Duke Math J 166(16):3147–3218, 2017), Ferretti (Compos Math 121(3):247–262, 2000), Ferretti (Duke Math J 118(3): 493–522, 2003), McKinnon and Roth (Invent Math 200(2): 513–583, 2015), Ru and Vojta (Amer J Math 142(3):957–991, 2020), Ru and Wang (Algebra Number Theory 11(10): 2323–2337, 2017), Ru and Wang (Int J Number Theory 18(1):61–74, 2022), Heier and Levin (Amer J Math 143(1): 213–226, 2021) and our related works (including Grieve (Michigan Math J 67(2):371–404, 2018), Grieve (Houston J Math 44(4):1181–1202, 2018), Grieve (Asian J Math 24(6):995–1005, 2020), Grieve (Acta Arith 195(4):415–428, 2020), Grieve (Res Number Theory 7(1):1, 14, 2021) and Grieve (C R Math Acad Sci Soc R Can 44(1):16–32, 2022)). Our main results may be described via the expectations of the Duistermaat-Heckman measures. For example, we prove that the expected orders of vanishing for very ample linear series along subvarieties may be calculated via the theory of Chow weights and Okounkov bodies. This result provides a novel unified viewpoint to the existing works that surround these topics. It expands on work of Mumford (Enseignement Math (2) 23(1-2):39–110, 1977), Odaka (Ann of Math (2) 177(2):645–661, 2013) and Fujita (Amer J Math 140(2):391–414, 2018). Moreover, it has applications for Diophantine approximation and K-stability. As one result of this flavour, we define a concept of uniform arithmetic $$\mathrm {K}$$ -stability for Kawamata log terminal pairs. We then establish a form of K. F. Roth’s celebrated approximation theorem for certain collections of divisorial valuations which fail to be uniformly arithmetically $$\mathrm {K}$$ -stable. This result builds on the Roth type theorems of McKinnon and Roth (Invent Math 200(2):513–583, 2015). Moreover, it complements the concept of arithmetic canonical boundedness, in the sense of McKinnon and Satriano (Trans Amer Math Soc 374(5):3557–3577, 2021), in addition to our results that establish instances of Vojta’s Main Conjecture for $${\mathbb {Q}}$$ -Fano varieties Grieve (Asian J Math 24(6):995–1005, 2020).

Unraveling the EFL expat: challenging privilege through borderlands and Asia as Method

Each year, multitudes respond to the demand for native English speakers to teach English as a Foreign Language (EFL) in Asian countries, particularly China, Japan, and South Korea. These EFL transnationals are often young, new to living abroad, and inexperienced as educators. When they arrive, they often find a community, and an identity waiting for them: that of the expatriate. In this paper, I draw on research on EFL expatriates to produce a figuration, a way of engaging with and highlighting contradiction and disjuncture in the narrative identity of EFL expat taken up by some transnational EFL teachers. This figuration serves as a nexus to which I bring two bodies of theory with which to think. These are the Borderlands Thought of Gloria Anzaldúa and Chen Kwan-Hsing’s articulation of Asia as Method. Separately, I bring these into conversation with the figuration of the EFL expat, then consider what emerges when all three are brought together. In doing so, I highlight how the figuration of the EFL expat is outlined by privileged and constrictive colonial, racial, professional, and linguistic dichotomies. The theories of Anzaldúa and Chen help to unravel these binaries, suggesting ways in which transnational English teachers can move on from such constraints to become something more than in-but-not-of their local world. I also consider what it means for Western scholars to work respectfully in theoretical spaces that were not developed by and for them, proposing that such researchers can think of themselves as theoretical expatriates.

Size dependent generalized thermoelasticity: Green-Lindsay theory with modified strain gradient theory

The present work is a development of the Green-Lindsay (GL) thermoelasticity theory for micro continuum bodies. The micro continuum modified strain gradient theory is used here based on the Green-Lindsay theory of the micro continuum media. In fact, the present work is a combination of Green-Lindsay thermoelasticity theory with modified strain gradient continuum theory. All assumptions of GL and modified strain gradient theory are satisfied and the final general forms of constitutive relations and also heat conduction equation are extracted. As an application of the derived formulation, a one-dimensional microlayer is considered and the newly derived equations are applied to it. Finally, the governing equations of coupled generalized thermoelasticity of the microlayer are solved using the Chebyshev collocation method. Effects of microscale parameters appearing in modified strain gradient theory on the dynamic thermo-elastic response of microlayer are investigated.

Body Politics and Embodied Subjectivity in Margaret Atwood’s “The Man from Mars”

ABSTRACT Published in Margaret Atwood’s first short story collection Dancing Girls in 1977, “The Man from Mars” offers a fictional representation of body politics through Atwood’s young protagonist, Christine, whose experience of her embodiment becomes a discursive agent through which various forms of displacement are foregrounded. Through a critical exploration of Christine’s experience of her body in the private and public realms, this essay aims to offer a reading of the story in the context of the embodied self and subjectivity while examining how the acculturation of bodily consciousness and idealised body images are conducive to feelings of personal insecurity as well as social intolerance towards difference. By exploring Atwood’s construction of her fat heroine in the light of body and embodiment theories and in dialogue with Atwood’s other literary works, this essay thus seeks to look into the ways in which “The Man from Mars” casts a critical eye on body politics situating it side by side with identity politics through the art of the modern short story.

Rewilding Shouldn’t Be Reactive: Fragas do Eume Natural Park in the Face of an Invasive Alien Species

Rewilding is growing worldwide as a conservation approach to face the restoration of all natural processes that are suppressed or degraded by human action. After plenty of theoretical discussion and some limited experimental practices, rewilding remained conceptually open and diverse with regard to its operational framework. However, little was discussed with regards invasive alien species (IAS) management within rewilding. Hence, the aim of this research is to bridge the gap between these two bodies of theory. To do so, this work explores, in situ, a protected area in which rewilding is discoursively expressed as a form of native forest conservation. Based on a qualitative approach, the results gather stakeholders’ discourses on the institutional advocacy for rewilding, expressed as a form of incentivizing land abandonment and hence leading to a decline in the plantation of invasive blue gums (Eucalyptus globulus). The research poses a discussion on the problematic assimilation that rewilding and IAS management may have when informally combined. Lastly, it is concluded that, when executed in coexistence with IAS, rewilding projects should elude reactive positions and, instead, formalize agreed restoration programs, so that conflictive IAS can be consensually treated together with landowners.

Quality Analysis of Railroad Train Shunting Operation Plan Using the Intelligent Body Model

Shunting work is an important component part of railway transport production and is an important link in realizing the train marshalling plan and the train operation map, accelerating the rotation of vehicles, and completing the task of transport production. With the present, the gradual construction of passenger dedicated lines and high-speed train operation bring a new dawn to railroad transportation on the one hand, but on the other hand, high-speed train operation makes the process of train operation more complicated, and the safety hazards and uncontrollable factors of trains are higher than before. Compared with existing lines, passenger dedicated lines put forward higher requirements on the performance of train operation and dispatching system, requiring better real-time, intelligence, and interactive response characteristics of the train operation and dispatching system. The construction of passenger dedicated lines and the increase in train operation speed have put forward higher requirements for safe, on-time, and high-efficiency train operation. The train operation scheduling system is one of the cores of intelligent railroad transportation system, which is the guarantee of safe and on-time train operation. This requires the search for new control strategies to meet the requirements of high-speed train operation and multiple objectives of safety, punctuality, and comfort. Train operation scheduling is a typical distributed system. At present, there are still problems in the safety of railway shunting operations, such as disconnection in management and implementation, failure to revise some rules and regulations, frequent occurrence of obstacles in equipment and facilities, and substandard quality of operators. Therefore, it is necessary to make a systematic analysis of the current situation of railway shunting safety and propose countermeasures and measures. By studying the structure of intelligent body and multi-intelligent body theory, it decomposes the influencing factors of railroad shunting operation, designs the intelligent body model of each element, and applies it in train shunting operation to improve the quality of railroad shunting operation.

The Bodily Theory of Pain

One use of the noun ‘pain’ is exemplified in sentences like ‘There is a pain in my foot’. According to the Experiential Theory, ‘pain’ in this context refers to an experience located in the mind or brain. According to the Bodily Theory, it refers to an extra-cranial bodily occurrence located in a body part. In this paper, I defend the Bodily Theory. Specifically, I argue that pains are proximal activations of nociceptors that cause experiences of pain. This view is preferable to the Experiential Theory, because it accords better with common sense and offers a better interpretation or semantics of ordinary pain reports.

Hydrodynamic interactions are key in thrust-generation of hairy flagella

The flagellum in many predatory flagellates is equipped with rigid hairs, which reverse the direction of thrust to generate a feeding current. We have discovered a novel mechanism for thrust generation with hairy flagella, which is fundamentally different from the slender body theory governing smooth flagella. We show that the thrust is generated at the crests of the flagellar wave, thanks to the key role of hydrodynamic interactions among hairs, effectively functioning like a sheet. The mechanism suggests that the optimal flagellum should be long and curvy, consistent with the diverse designs of hairy flagella observed in nature.

On the Iterlayer Contact Conditions in Multilayer Thin Body Theory and Some Issues of Splitting Initial-Boundary Value Problems

On the Iterlayer Contact Conditions in Multilayer Thin Body Theory and Some Issues of Splitting Initial-Boundary Value Problems

Peran dan Kedudukan Dewan Gelar, Tanda Jasa Dan Tanda Kehormatan Dalam Sistem Ketatanegaraan Di Indonesia

The aim of this study is to determine the role and position of the Dewan Gelar, Tanda Jasa dan Tanda Kehormatan (Dewan GTK) in the Administration System in Indonesia. The research method used is empirical normative research using a statutory approach. The results of the study found that Dewan GTK is a supporting institution or state auxiliary bodies or auxiliary institutions for executive power in the system of state administration in Indonesia. According to the theory of State Auxiliary Bodies (SAB), Dewan GTK includes Executive-Auxiliary, namely SAB that is included in the executive realm in general at the auxiliary level. In this category there are two different types of SAB functions which are to coordinate and to provide policy suggestions / recommendations to the President which based on its formation consists of two, namely, formed by the President and the second formed to represent certain groups to provide advice and input to the government. Dewan GTK is included as Auxiliary-Advisory, namely SAB which provides advice and considerations to the President.

Контактная задача о взаимодействии штампа в форме параболоида вращения и пороупругого слоя, закрепленного на упругом основании

The contact problem of the introduction of a rigid punch in the form of a paraboloid of rotation into a poroelastic layer fixed on an elastic half-space is considered on the basis of the equations of the theory of poroelastic bodies of Cowin-Nunziato. It is assumed that there is no friction in the contact zone. With the help of the Hankel integral transformation, the problem posed is reduced to solving the integral equation for an unknown contact stress. The collocation method is used to solve the integral equation. The area of contact, the values of contact stresses are found, and the deformation of the surface outside the punch is investigated. The relationship between the force acting on the punch and its displacement has also been investigated. A comparative analysis of the studied quantities for different values of the parameters of the poroelastic layer and the elastic foundation has been carried out. Numerical results are presented in the form of graphs.

A semi-analytical solution for energy harvesting via the elastic motion of the circular floater of aquaculture cages attached with piezoelectric

This work's unique research objective is to assess the possibility of energy harvesting by attaching the piezoelectric patches on the high-density polyethylene floater of aquaculture fish cages. Using Euler-Bernoulli's curved beam theory, the vertical elastic motion of the floater in regular linear sea waves was modeled semi-analytically based on slender body theory and matched asymptotic expansions. Regular linear waves refer to the single frequency waves with small amplitudes compared to the wavelength, for which the linear airy wave theory can approximate the wave characteristics. When the floater elastic motions are determined, the resultant strain is implemented to the governing equation of piezoelectric patches to calculate the generated power. The effect of some variables such as wavenumber, floater bending stiffness, relative floater dimension, and the number of patches in the circumference of the floater on the generated power was investigated. The results indicate that by installing the patches in the proper place, the floater can produce the required electrical power supplying some low-powered electric sensors for monitoring sea environmental conditions or other applications. Also, as a suggestion, installing piezoelectric patches throughout the perimeter of a semi-submerged circular elastic floater is a way of energy harvesting from sea waves.

Numerical study on the aerodynamic and acoustic scale effects for high-speed train body and pantograph

Based on computational fluid dynamics (CFD) and Lighthill acoustic analogy theory, the aerodynamics and acoustic scale effects of high-speed train bodies and pantographs are numerically studied, by changing the model scale. The model scales are 1/1, 1/2, 1/4 and 1/8 respectively. The aerodynamic force, flow field behavior, surface pressure and far-field noise of the train body and pantograph models, at different model scales are compared and analyzed. The numerical simulation is in good agreement with the experiment. The reliability of the numerical calculation method has been proven. The results show that as the scale of the model decreases, the root mean square (RMS) value and the degree of fluctuation of the aerodynamic drag coefficient of the pantograph increase. In addition, the aerodynamic drag coefficient of the train body increases, but the degree of fluctuation decreases. The similarity of the unsteady flow field of the pantograph at different model scales is strong, but the similarity of the train body is weak. The main frequency and power spectral density distribution of the pulsating pressure on the surface of the pantograph have obvious corresponding relationships with the model scale, but the train body has no obvious regularity. The longitudinal and lateral propagation characteristics of aerodynamic noise from the train body and pantograph are not affected by the model scale, but the sound pressure level changes. Compared with the train body, the far-field aerodynamic noise of the pantograph is less affected by the model scale. The energy distribution of noise is also affected by the scale of the model. As the model scale decreases, the energy concentration range of radiated noise will change from low frequency to medium high frequency.

A dynamical study on sea waves interaction with an array of circular elastic floaters of aquaculture fish cages

In this paper, linear oblique wave incident to circular elastic floaters of aquaculture fish cages was studied semi-analytically. This work's unique research objectives include considering the array of elastic floaters where each floater consists of two tori with minor differences in their main radii. Hydrodynamic interaction between the inner and outer of each floater body and hydro-elastic interaction between floaters in the array are the particular features of the problem. Using slender body theory and matched asymptotic expansions, each 3D problem was decomposed into two separate, more straightforward problems named near-field and far-field problems. This approach helps derive fundamental solutions for symmetric and antisymmetric motions. Also, using linear wave theory, the diffracted and radiated waves due to the presence of floaters were expressed in Fourier modes of symmetric and antisymmetric motions. Moreover, Graf's and Gegenbauer's addition theorems for Bessel functions are used to shift between different coordinate systems. This approach is helpful to bridge on calculating related integrals numerically. The developed model verification by BEM-based software demonstrates that the model solves the mathematical formulas with enough accuracy. The effect of various parameters such as floater dimensions, wavenumber, the distances between floaters, and the bending stiffness of floater on the floater's motions was studied. The results demonstrate that as the wavenumber increases, the floater's hydro-elastic interaction becomes essential. Furthermore, the upstream floaters do encounter larger wave loads than a single floater in waves.

Exact tricritical point from next-to-leading-order stability analysis

In the massive chiral Gross-Neveu model, a phase boundary separates a homogeneous from an inhomogeneous phase. It consists of two parts, a second order line and a first order line, joined at a tricritical point. Whereas the first order phase boundary requires a full, numerical Hartree-Fock calculation, the second order phase boundary can be determined exactly and with less effort by a perturbative stability analysis. We extend this stability analysis to higher order perturbation theory. This enables us to locate the tricritical point exactly, without need to perform a Hartree-Fock calculation. Divergencies due to the emergence of spectral gaps in a spatially periodic perturbation are handled using well established tools from many body theory.

The Application of Biomechanics Combined with Human Body Structure in Volleyball Technical Analysis.

With the development of volleyball, the development of traditional school volleyball has been paid increasing attention. This has also aroused the concern of schools, coaches, and athletes and has become the focus of volleyball development and reserve talent training. The purpose of this paper is to use the knowledge of biomechanics to study serving technology and attacking technology in volleyball. In the aspect of biomechanics, this paper proposes the finite element modeling theory of the human body. The upper limbs of volleyball players are modeled and analyzed, and four powerful teams are selected for video analysis of volleyball offensive skills. The overall difference between athletes in different groups is very obvious. The phase with the longest time and the greatest difference was the P3 phase, which took 0.802 ± 0.085 seconds.

A slender body theory for the motion of special Cosserat filaments in Stokes flow

The motion of filament-like structures in fluid media has been a topic of interest since long. In this regard, a well known slender body theory exists, wherein the fluid flow is assumed to be Stokesian while the filament is modeled as a Kirchhoff rod which can bend and twist but remains inextensible and unshearable. In this work, we relax the inextensibility and unshearability constraints on filaments, i.e., the filament is modeled as a special Cosserat rod. Starting with the boundary integral formulation of Stokes flow involving the filament’s surface velocity and fluid traction that acts on the filament surface, the method of matched asymptotic expansion is used to first obtain a leading-order representation of the boundary integral kernels in the filament’s aspect ratio. We then substitute Fourier series expansion (in filament’s circumferential coordinate) of both the filament’s surface velocity and fluid traction in the aforementioned leading-order representation and further linearize it in the rod’s shear strains to reduce the two-dimensional boundary integral over the filament surface into a line integral over the filament’s centerline. Upon further collecting the coefficients of sine and cosine terms, the zeroth-order Fourier mode yields a line integral equation relating the rod’s centerline velocity with the distributed fluid force that acts on the filament. The presence of line integral makes the relation non-local in nature. On the contrary, the first-order Fourier mode yields a simpler local relation between the rod’s angular velocity and the distributed fluid couple. The line integral equation is shown to reduce to the classical slender body theory when shear strains and axial strain are set to zero. The non-dimensional governing equations of the special Cosserat rod are also derived accounting for the distributed fluid force and distributed fluid couple in them which are solved to obtain the filament motion. The presented theory is demonstrated with an example problem of the tumbling of filaments in background shear flow. We show that for relatively shorter filaments where the effect of shear and axial stretch is more dominant, the obtained results deviate from the ones based on the classical slender body theory.

Is Khelobedu a language or a dialect?

The primary aim of this article is to investigate whether Khelobedu should be considered a language in its own right or whether it has correctly been classified as one of the dialects of Sepedi, referred to in Section 6(1) of the Constitution of the Republic of South Africa, as Sepedi, one of the 11 official languages of South Africa. The article was initiated by a dialectal controversy surrounding the politics of dialects and languages in South Africa. Dialectology as a conceptual framework was considered as the body of theory that guides this article and buttresses the authors’ point of view. The article is purely qualitative in nature and employed content analysis supplemented by focus group interviews with members of the Modjadji Traditional Council and face-to-face interviews with 20 university students who ethnically identified themselves as Balobedu. Participants for the article were purposively selected based on their proficiency and knowledge about the researched phenomenon as articulated by Creswell and Creswell. Based on lexical dissimilarities realised between Khelobedu and Sepedi, the article concludes that Khelobedu is not a dialect, but a language on its own. The findings reveal that the decision to classify Khelobedu as a dialect of Sepedi was meant to accommodate the administrative system of the apartheid regime, being a purely political exercise which lacked transparency, consultation and a linguistic justification. It is further found that decisions about whether speech forms constitute an independent language or a dialect are based on language ideology and not on linguistic criteria.

Sex, sahibs and bodies: women workers in the tea plantations of colonial Assam

ABSTRACT The recent developments in the evolution of ‘labor history’ as an academic field have injected new direction into theories of Gender, Sex and Bodies. Incidents of sexual violence and gender oppression have long been a brutal part of human history. In contemporary times, plantation societies are finally receiving critical attention as historians embark on gendered reappraisals of history, especially in countries like India. This article sets out to retrieve several accounts of sexual violence in the tea plantations of Assam during the colonial period. It also shows how the colonial masters (Sahibs) of the tea gardens have oppressed/sexualized the bodies of men/women workers in the tea gardens of Assam. An attempt is also made to reconstruct the forgotten stories of two tea-garden working-class women, Mangri Orang alias Malati Mem and Durgi Bhumij alias Durgi Mem, who were sexually abused by the European tea planters. From their objectification as sexualized bodies, the duo later showed their abilities of agency when they joined India’s freedom struggle and transformed into freedom fighters. The paper analyzes the connections between oppressed/sexualized bodies of women tea plantation workers and the colonial capitalist patriarchy in the history of Assam.