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Bifurcation in a Leslie–Gower system with fear in predators and strong Allee effect in prey
No full textIn this paper, we consider a modified Leslie–Gower predator–prey model with Allee effect on prey and fear effect on predators. Results show complex dynamical behaviors in the model with these factors. Existence of equilibrium points and their stability of the model are first given. Then it is found that, with the Allee and fear effects, the model exhibits various and different bifurcations, such as saddle-node bifurcation, Hopf bifurcation, and Bogdanov–Takens bifurcation. Theoretical analysis is verified through some numerical simulations
Analysis and exact solutions for reaction–diffusion predator–prey system with prey-taxis by phi6 method
No full textThis article analyses the biomathematical model that describes the reaction–diffusion predator–prey system with prey-taxis. The analysis includes addressing the question of whether the solution exists and is unique. The next goal is to obtain the exact solutions. The ɸ6 method has been utilized for this purpose. The simulations of the obtained solutions are also incorporated, providing a broader understanding of the solutions
A revisit to tail risk measures in the presence of bivariate regularly varying tailed insurance and financial risks
No full textConsider a discrete-time insurance risk model in which the one-period insurance and financial risks are assumed to be independent and identically distributed random pairs, but a strong dependence structure is allowed to exist between each pair. Recently, Q. Tang and Y. Yang employed a framework of bivariate regular variation to model the heavy tails and the dependence of the insurance and financial risks, and they also established an asymptotic formula for the finite-time ruin probability [Interplay of insurance and financial risks in a stochastic environment, Scand. Actuar. J., 2019(5):432–451, 2019]. In this paper, by adopting a different approach, we study the asymptotic behavior of some tail risk measures for the aggregate discounted net loss, including the tail probability and the conditional loss-based tail expectation. We show both analytically and numerically how the heavy tailedness and the dependence of each pair of insurance and financial risks affect the tail risk measures
Background risk model in presence of heavy tails under dependence
No full textIn this paper, we examine two problems on applied probability, which are directly connected with the dependence in presence of heavy tails. The first problem is related to max-sum equivalence of the randomly weighted sums in bivariate setup. Introducing a new dependence, called generalized tail asymptotic independence, we establish the bivariate max-sum equivalence under a rather general dependence structure when the primary random variables follow distributions from the intersection of the dominatedly varying and the long-tailed distributions. Based on this max-sum equivalence, we provide a result about the asymptotic behavior of two kinds of ruin probabilities over a finite-time horizon in a bivariate renewal risk model with constant interest rate. The second problem is related to the asymptotic behavior of the tail distortion risk measure in a static portfolio called background risk model. In opposite to other approaches on this topic, we use a general enough assumption that is based on multivariate regular variation
A new dynamic model for simultaneous saccharification and fermentation process of rice wine
No full textIn this paper, a new fractional model for the simultaneous saccharification and fermentation process of rice wine is proposed. To begin with, the existence and uniqueness of solution to the new model are proved by using some fixed point theorems. In addition, the stability at the equilibrium point and the Ulam–Hyers stability of the fractional simultaneous and saccharification fermentation model are analyzed. Then the approximate solutions of the fractional simultaneous saccharification and fermentation model are obtained by using the generalised Euler method. Finally, numerical simulations are given to verify the rationality of the fractional simultaneous saccharification and fermentation model. The new model proposed in this paper can more sensitively capture changes in the reaction
Science and Social Anthropology: Resolving Hierarchical and Horizontal Knowledge Structures
No full textThe relationship between social anthropology and the so-called ‘natural’ sciences has a long and fraught history, beginning with the field’s inception in the 1870s. Despite periodic attempts at thematic reinvention, social anthropology consequently remains trapped in what has been termed a ‘pre-paradigmatic’ state, without consensus among social anthropologists on either a self-consistent object of study for their field, parameters of study, or a causal model for explaining that object. Pedagogic sociology offers a causal explanation for this lack of integration, by describing how formal education systems define and segregate ‘natural’ and ‘social’ sciences, and by further describing a mechanism for achieving desegregation. Corroborating observations made by both natural scientists and social anthropologists, this chapter uses a pedagogic sociological model to describe the lack of integration between natural and social science generally, and between natural science and social anthropology in particular. This pedagogic sociological model is then used to describe a potential pathway towards a resolving integration between social anthropology and natural science, with reference to incipient formal empirical methods and to Cultural Model Theory
An Easy Framework to Organize Complex Data
No full textThe holistic and multidimensional nature of anthropological research results in an enormous amount of data, but the problem is how to organize it in such a way as to be useful for identifying complex patterns across different fields. This paper proposes a basic Framework for organizing metadata into categories: Space (where), Time (when), Matter (who and what), and Energy (how), and then separates these into two categories: empirical data and ideational data. This method reduces preconceptions by separating out the tangible evidence from the intangible and allows evidence to be understood and tested from different perspectives. 
Historical Legacies of the Pre-industrial Family Systems: Cohabitation
No full textThis paper discusses a cultural explanation for the rise of cohabitation in the last decades in Europe. For doing so, I approach this phenomenon from the field of historical legacies of pre-industrial family systems. The literature regarding the history of marriage and cohabitation points that, before the institutionalization of marriage, different characteristics of family systems and family norms (such as co-residence of parents with their adult children, dowry, or inheritance) were relevant to explain why some regions in Europe had a higher use of cohabitation (called back then informal marriage). Regarding the current rise of this practice, the Second Demographic Transition theory (SDT) points to the ideational change toward individualism and anti-conformism as the main cause of the rise of cohabitation. And, not surprisingly, the literature about legacies of historical family systems recently connected preindustrial family features (such as the number of generations living in the same household) with the persistence of the values and attitudes that seem to be linked to the recent changes in family formation. These 3 bodies of literature highlight the potential of the field of historical legacies of the family to explain the current family behavior, such as cohabitation
Pointwise Hypothesis Testing of Biomedical Near-Infrared Spectroscopy Signals
No full textThis study uses a pointwise statistical approach to analyze Near-Infrared Spectroscopy (NIRS) signals in preterm infants with and without Patent Ductus Arteriosus (PDA). Three oxygenation signals—SpO2, rSO2-1 (cerebral), and rSO2-2 (renal)—were analyzed across no-PDA, PDA, and hsPDA groups. Smoothed signals were tested using pointwise ANOVA and Tukey HSD to detect significant group differences. Results showed distinct patterns in rSO2-1 and rSO2-2, with the hsPDA group standing out in rSO2-1 and the no-PDA group in rSO2-2, demonstrating the value of this method in biomedical signal analysis
Verslo valdymo sistema – sprendimas efektyvesniam ikimokyklinio ugdymo procesų valdymui
No full textIkimokyklinio ugdymo įstaigos atlieka svarbų vaidmenį vaikų socialinėje ir akademinėje raidoje, tačiau jų veiklos valdymas neretai susiduria su administraciniais ir organizaciniais iššūkiais. Skaitmenizavimas tampa esminiu įrankiu, padedančiu optimizuoti procesus, palengvinti administracinį darbą ir gerinti ugdymo kokybę. Nepaisant technologinių galimybių, švietimo įstaigos dažnai naudoja nesuderintas sistemas, kurios apsunkina duomenų valdymą ir neefektyviai išnaudoja darbuotojų laiką. Todėl atsiranda poreikis vieningai sistemai, kuri užtikrintų sklandų duomenų mainymąsi ir veiklos valdymą. Šio darbo tikslas – išanalizuoti skaitmenizavimo poveikį ikimokyklinio ugdymo įstaigoms, įvertinti dabartinių informacinių technologijų taikymo efektyvumą ir pasiūlyti vieningos sistemos galimą sprendimą