A colony of the queenless ant species, \emph{Pristomyrmex punctatus}, can broadly be seen as consisting of small-body sized worker ants and relatively larger body-sized cheater ants. Hence, in the presence of inter-colony migration, a set of constituent colonies act as a metapopulation exclusively composed of cooperators and defectors. Such a set-up facilitates an evolutionary game-theoretic replication-selection model of population dynamics of the ants in a metapopulation. Using the model, we analytically probe the effects of territoriality induced hostility. Such hostility in the ant-metapopulation proves to be crucial in preventing the tragedy of the commons, specifically, the workforce, a social good formed by cooperation. This mechanism applies to any metapopulation -- not necessarily the ants -- composed of cooperators and defectors where inter-population migration occurs asymmetrically, i.e., cooperators and defectors migrate at different rates. Furthermore, our model validates that there is evolutionary benefit behind the queenless ants' behavior of showing more hostility towards the immigrants from nearby colonies than those from the far-off ones. In order to calibrate our model's parameters, we have extensively used the data available on the queenless ant species, \emph{Pristomyrmex punctatus}
Mehrbod Zarifi, Mohamad Amin Jamshidi, Zolfa Anvari
et al.
Hydraulic systems have been one of the most used technologies in many industries due to their reliance on incompressible fluids that facilitate energy and power transfer. Within such systems, hydraulic cylinders are prime devices that convert hydraulic energy into mechanical energy. Some of the genuine and very common problems related to hydraulic cylinders are leakages. Leakage in hydraulic systems can cause a drop in pressure, general inefficiency, and even complete failure of such systems. The various ways leakage can occur define the major categorization of leakage: internal and external leakage. External leakage is easily noticeable, while internal leakage, which involves fluid movement between pressure chambers, can be harder to detect and may gradually impact system performance without obvious signs. When leakage surpasses acceptable limits, it is classified as a fault or failure. In such cases, leakage is divided into three categories: no leakage, low leakage, and high leakage. It suggests a fault detection algorithm with the basic responsibility of detecting minimum leakage within the Hydraulic system, and minimizing detection time is the core idea of this paper. In order to fully develop this idea, experimental data collection of Hydraulic systems is required. The collected data uses pressure sensors and other signals that are single-related. Due to the utilization of Long Short-Term Memory (LSTM) recurrent neural networks, more complex data analysis was enabled, which the LSTM-based leakage detection algorithm successfully achieved, providing almost 96% accuracy in classifying leakage types. Results demonstrate that the proposed method can perform real-time and online fault diagnosis for each cycle, reducing maintenance costs and prolonging the hydraulic system's lifespan.
We determine the tail asymptotics of the stationary distribution of a branching process with immigration in a random environment, when the immigration distribution dominates the offspring distribution. The assumptions are the same as in the Grincevičius--Grey theorem for the stochastic recurrence equation.
Humans have built stable systems for their social lives, although they are animals in motion. Whether people want to settle or move might depend on their characteristics, such as personality and social psychology. This chapter outlines the historical transition of mobility in Japan and Europe, including mobility away from daily life in the middle ages and mobility for pleasure in the early modern period. Then, we introduce a web-based questionnaire survey that examined human characteristics influencing life space mobility, and the relationship between mobility characteristics and their well-being. Several factors influencing either the life space mobility or the subscale of well-being were obtained from the large-scale web-based survey. Ego-resiliency is the ability to cope with and adapt to situations, and it can be said that humans were migrating from place to place because they possessed this ability. The results of this survey showed that ego-resiliency affects both mobility and well-being, and the essentiality of this ability was reaffirmed. “Diversion,” in which people try to get away from their daily routines, was a key factor influencing both mobility and well-being. Finally, we describe the importance of diversion based on the outline of mobility and diversion in the modern period.
Migration within the last three centuries centres on economics, shifts in government policies, and general concepts surrounding migrating children. However, this chapter asks a fundamental question, ‘what happened to the children? Over the last three centuries, children have been born along the journey. Accompanied and unaccompanied children have been and continue to be the forgotten collateral damage. The chapter explores the critical role of protection, prevention, and harm to migrating children. It addresses gaps and noncompliance with the ratified treaty, the UN Convention on the Rights of the Child over the last three decades, international migration in countries of origin, transit, destination, and return, to include the lifetime of impact on their health.
We study the stochastic hydrodynamics of colonies of flagellated swimming cells, typified by multicellular choanoflagellates, which can form both rosette and chainlike shapes. The objective is to link cell-scale dynamics to colony-scale dynamics for various colonial morphologies. Via autoregressive stochastic models for the cycle-averaged flagellar force dynamics and statistical models for demographic cell-to-cell variability in flagellar properties and placement, we derive effective transport properties of the colonies, including cell-to-cell variability. We provide the most quantitative detail on disclike geometries to model rosettes, but also present formulas for the dynamics of general planar colony morphologies, which includes planar chain-like configurations.
Mariem Abdellatif, Martin Friesen, Peter Kuchling
et al.
In this work we investigate limit theorems for the time-averaged process $\left(\frac{1}{t}\int_0^t X_s^x ds\right)_{t\geq 0}$ where $X^x$ is a subcritical continuous-state branching processes with immigration (CBI processes) starting in $x \geq 0$. Under a second moment condition on the branching and immigration measures we first prove the law of large numbers in $L^2$ and afterward establish the central limit theorem. Assuming additionally that the big jumps of the branching and immigration measures have finite exponential moments of some order, we prove in our main result the large deviation principle and provide a semi-explicit expression for the good rate function in terms of the branching and immigration mechanisms. Our methods are deeply based on a detailed study of the corresponding generalized Riccati equation and related exponential moments of the time-averaged process.
The computer tools used by architects have been improved significantly over the past 60 years, and they have evolved according to a complex scheme that embraces many concerns both within and outside the architectural community. By focusing on the ability of these different tools to return information to designers, by feedbacks, this paper will examine the different historical trends that have guided these improvements and identify the implications that these technologies have had on architectural design processes.This historical review shows that the arrival of digital technologies has raised many questions about the constitution of design processes, as well as the place to be given to these tools. The goal is to show that the knowledge embedded by the various computer programs will have led to a real overhaul of design knowledge, as part of the implementation of a new epistemology, driven by digital design processes.
Geography (General), Colonies and colonization. Emigration and immigration. International migration
Resumo: O interesse global nas práticas de engajamento dos emigrantes em diáspora tem crescido um pouco por todo o mundo. São disso exemplo as políticas ligadas ao retorno de emigrantes qualificados, à promoção de brain gain, ou destinadas a estimular a formação de redes de diáspora. Através de políticas públicas e de uma estratégia de comunicação eficaz poderia ser possível, pelo menos do ponto de vista do país de origem, reverter o sentimento de perda sociológica que representa a emigração de uma parte da sociedade nacional. Baseado num mapeamento global do movimento associativo português, o artigo encontra-se estruturado em duas partes. Na primeira parte, discutem-se as perspetivas teóricas que têm analisado as políticas e as práticas de vinculação dos migrantes aos seus países de origem. Na segunda, partindo da análise da recente emigração portuguesa, analisam-se, através de uma proposta de tipologia, as atuais formas organizativas dos portugueses no exterior.
Colonies and colonization. Emigration and immigration. International migration
In this paper the asymptotic behaviour of a critical 2-type Galton-Watson process with immigration is described when its offspring mean matrix is reducible, in other words, when the process is decomposable. It is proved that, under second or fourth order moment assumptions on the offspring and immigration distributions, a sequence of appropriately scaled random step processes formed from a critical decomposable 2-type Galton-Watson process with immigration converges weakly. The limit process can be described using one or two independent squared Bessel processes and possibly the unique stationary distribution of an appropriate single-type subcritical Galton-Watson process with immigration. Our results complete and extend the results of Foster and Ney (1978) for some strongly critical decomposable 2-type Galton-Watson processes with immigration.
Avtorja v članku predstavljata Adamičevo vlogo v drugi svetovni vojni, v kateri je deloval v okviru ameriških organizacij, kakršni sta bili Commom Council for American Unity in Vladna komisija za narodno obrambo. Pri tem se je zavzemal za upoštevanje etnične raznolikosti ameriškega prebivalstva pri aktiviranju v vojnih naporih ZDA. Adamič je bil tudi vodilni član organizacij ameriških južnoslovanskih izseljencev, kakršna sta bila Združeni odbor južnoslovanskih Američanov in Slovenski ameriški narodni svet. Ker novejša ameriška literatura delovanje jugoslovanskih Američanov med drugo svetovno vojno obravnava zlasti kot problem nacionalne varnosti ZDA, nam odkriva doslej še ne razkrito plat delovanja Louisa Adamiča.
Colonies and colonization. Emigration and immigration. International migration
Vasil Yasenov, David Hausman, Michael Hotard
et al.
Immigration legal services providers (ISPs) are a principal source of support for low-income immigrants seeking immigration benefits. Yet there is scant quantitative evidence on the prevalence and geographic distribution of ISPs in the United States. To fill this gap, we construct a comprehensive, nationwide database of 2,138 geocoded ISP offices that offer low- or no-cost legal services to low-income immigrants. We use spatial optimization methods to analyze the geographic network of ISPs and measure ISPs' proximity to the low-income immigrant population. Because both ISPs and immigrants are highly concentrated in major urban areas, most low-income immigrants live close to an ISP. However, we also find a sizable fraction of low-income immigrants in underserved areas, which are primarily in midsize cities in the South. This reflects both a general skew in non-governmental organization service provision and the more recent arrival of immigrants in these largely Southern destinations. Finally, our optimization analysis suggests significant gains from placing new ISPs in underserved areas to maximize the number of low-income immigrants who live near an ISP. Overall, our results provide vital information to immigrants, funders, and policymakers about the current state of the ISP network and opportunities to improve it.
Rachel Los, Duco van Holthe tot Echten, Gerhard Nordemann
et al.
Colonies of rod-shaped bacteria constitute a system of colloidal active matter with nematic properties. As a single initial bacterium multiplies through repeated divisions, the resulting colony quickly loses long-range orientational order, but retains locally ordered domains. At the boundaries of these domains, topological defects emerge, which move around randomly as the colony grows. In both experiments and simulations, we find that these defects are created at a rate that corresponds to the exponential growth of the colony, resulting in a stable defect density. Both this defect density and the colony's correlation length are regulated by the aspect ratio of the rod-shaped particles. Moreover, we find that the defect dynamics are well described by a Gamma distribution, which is due to repeated divisions and subsequent re-orientations of the bacteria.
In this paper, we consider Galton-Watson processes with immigration. Pick $i(\ge2)$ individuals randomly without replacement from the $n$-th generation and trace their lines of descent back in time till they coalesce into $1$ individual in a certain generation, which we denote by $X_{i,1}^n$ and is called the coalescence time. Firstly, we give the probability distribution of $X_{i,1}^n$ in terms of the probability generating functions of both the offspring distribution and the immigration law. Then by studying the limit behaviors of various functionals of the Galton-Watson process with immigration, we find the limit distribution of $X_{2,1}^n$ as $n\rightarrow\infty.$
This article has as its main purpose to analyze the way by which the daily papers O Estado de S. Paulo (OESP) andFolha de São Paulo (FSP), important means of communication in Brazil, published some news concerning the so called Independent Foreign Policy – PEI (1961-1964). Regarded as an inflection point in Brazil foreign actions, PEI linked to the developmental-national project received severe reviews from the referred daily papers, which corroborated to the opinions and the conducts of the sectors more inclined to the right wing political spectrum. We want to demonstrate that OESP and FSP, as from an anti-communist discourse, contributed to stereotyped views about foreign policy formulated during Jânio Quadros government, and implemented later on by João Goulart government, being one of the elements that justified the civil-military stroke in 1964.
International relations, Colonies and colonization. Emigration and immigration. International migration
As the external borders between Finland and its neighbouring countries have become more permeable for some migrants after the collapse of the Soviet Union and the EU enlargement, the internal borders have become more ubiquitous and enforced by various kinds of bordering practices. Drawing on a qualitative research on Russian-speaking women engaged in commercial sex in Finland, we have examined the everyday material consequences of policies and bordering practices. We have distinguished different sites in which everyday bordering takes place: rental markets, banking and law enforcement. Our analysis demonstrates the importance of analysing commercial sex from an everyday perspective. This perspective reveals that even women with formal citizenship can be subjected to various bordering practices due to the criminalisation of commercial sex and the stereotypes attached to Russianspeaking women. We have argued for the need to expand on the notion of “deportability” as it not only concerns non-citizens but also naturalised foreigners.
Colonies and colonization. Emigration and immigration. International migration, Communities. Classes. Races
We give sufficient conditions on the initial, offspring and immigration distributions under which the distribution of a not necessarily stationary Galton--Watson process with immigration is regularly varying at any fixed time.