scholarly journals Indirect Taxis on a Fluctuating Environment

Mathematics ◽  
2020 ◽  
Vol 8 (11) ◽  
pp. 2052
Author(s):  
Andrey Morgulis ◽  
Konstantin Ilin

In this article, we study a Patlak–Keller–Siegel (PKS) model of a community of two species placed in the inhomogeneous environment. We employ PKS law for modeling tactic movement due to interspecific taxis and in response to the environmental fluctuations. These fluctuations can arise for natural reasons, e.g., the terrain relief, the sea currents and the food resource distribution, and there are artificial ones. The main result in the article elucidates the effect of the small-scale environmental fluctuations on the large-scale pattern formation in PKS systems. This issue remains uncharted, although numerous studies have addressed the pattern formation while assuming an homogeneous environment. Meanwhile, exploring the role of the fluctuating environment is substantial in many respects, for instance, for predicting the side effects of human activity or for designing the control of biological systems. As well, it is necessary for understanding the roles played in the dynamics of trophic communities by the natural environmental inhomogeneities—those mentioned above, for example. We examined the small-scale environmental inhomogeneities in the spirit of Kapitza’s theory of the upside-down pendulum, but we used the homogenization instead of classical averaging. This approach is novel for the dynamics of PKS systems (though used commonly for other areas). Employing it has unveiled a novel mechanism of exerting the effect from the fluctuating environment on the pattern formation by the drift of species arising upon the homogenization of the fluctuations.

Author(s):  
Andrey B. Morgulis ◽  
Konstantin I. Ilin

In this article, we explore a community of two species placed on the inhomogeneous environment. We assume interspecific taxis as well as responding to the environmental fluctuations by tactic movement. We study the effect of the small-scale environmental fluctuations on the large-scale dynamics of the community following the line of Kapitza's theory of the upside-down pendulum. It turns out that, the only conductor of the effect of the fluctuations on the large-scale patterns is some drift of species. When the fluctuation takes the form of a travelling wave, there exist the quasi-equilibria, which are equilibria on average, roughly speaking. Examining the stability of the quasi-equilibria shows that, compared to the case of the homogeneous environment, increasing the magnitude of the fluctuations can destabilize the quasi-equilibria as well as stabilize them. It depends only on the speed at which the fluctuation wave prop-agates which of these effects occurs. Anyway, the effect is exponential in the amplitude of the wave.


2019 ◽  
Vol 4 (12) ◽  
Author(s):  
C. Marchioli ◽  
H. Bhatia ◽  
G. Sardina ◽  
L. Brandt ◽  
A. Soldati

2016 ◽  
Vol 113 (17) ◽  
pp. 4688-4693 ◽  
Author(s):  
H. Clark Barrett ◽  
Alexander Bolyanatz ◽  
Alyssa N. Crittenden ◽  
Daniel M. T. Fessler ◽  
Simon Fitzpatrick ◽  
...  

Intent and mitigating circumstances play a central role in moral and legal assessments in large-scale industrialized societies. Although these features of moral assessment are widely assumed to be universal, to date, they have only been studied in a narrow range of societies. We show that there is substantial cross-cultural variation among eight traditional small-scale societies (ranging from hunter-gatherer to pastoralist to horticulturalist) and two Western societies (one urban, one rural) in the extent to which intent and mitigating circumstances influence moral judgments. Although participants in all societies took such factors into account to some degree, they did so to very different extents, varying in both the types of considerations taken into account and the types of violations to which such considerations were applied. The particular patterns of assessment characteristic of large-scale industrialized societies may thus reflect relatively recently culturally evolved norms rather than inherent features of human moral judgment.


Significance Although large-scale social protest in Bahrain has been cowed over the ten years since the ‘Arab uprisings’, small-scale demonstrations recur, reflecting a base level of discontent. Mobilising issues include economic pressures, limited political representation (especially of the Shia majority) and, most recently, ties with Israel. Impacts Despite protests, Israel’s and Bahrain’s respective ambassadors will keep up high-profile activity and statements. The authorities are likely to exaggerate the role of Iranian interference in order to deepen the Sunni-Shia divide. If Riyadh manages to extricate itself from the Yemen war, that could partly reduce the pressure on Manama.


Jurnal AKTUAL ◽  
2019 ◽  
Vol 16 (1) ◽  
pp. 47
Author(s):  
Aisah Aisah

Rice Milling Company is rice industry’s oldest and largest classified in Indonesia, which is able to absorb more than 10 million workers, handles more than 40 million tons of grain.  Rice Milling Company agro-industy is the central point, because this is where the main product is obtained in the form of rice and raw materials for advanced processing of food and industrial products.  Rice Miling Unit in the district of OKU Timur there is some skala, ranging form small-scale, medium-scale to large-scale.  Fuctional benefits of each different scale milling is also different.  The average rice farmers often sell gabahnya to the rice milling unit closest to the place residence, whether it is large-scale, medium and small.  Rice produced by the milling-grinding different quality.  Usually when a large-scale millimg yield of rice is cleaner than the other scale.  But it does not become a reference for milling grain milling usually depends on consumer demand.  The purpose of the study are : 1.  To determine levels of volume (tonnage) and the retention time of each service fuctional rice storage (barns) wich carried a different scale rice milling unit.  2.  To determine differences in the bebefits of economic transactions received by farmers and rice millers of different scale of business, especially when seen from the level of the milling costs, the purchase price of rice by rice milling unit, and the quality of milling services and service scale.  The result show that : the fuctional role of each is different milling.  Large-scale milling has three fuctional roles are : Processing, storage and distribution.  Medium-scale miling functional has two roles, namely : processing and distribution.  While small-scale rice milling unit has only two functional roles are : processing and storage.


This chapter extends the book’s insights about nature, technology, and nation to the larger history of the modern period. While the modern nation loses its grip as a locus of identity and analysis, attempts to understand the operation, disruption, and collapse of continental and global infrastructures continue to mix the natural and the machinic in ways that define them both. Those vulnerabilities emphasize large-scale catastrophe; historiographically, they mask the crucial role of small-scale failures in the experience and culture of late modernity, including its definition of nature. Historical actors turned the uneven geographical distribution of small-scale failures into a marker of distinctive local natures and an element of regional and national identity. Attending to those failures helps not only situate cold-war technologies in the larger modern history of natural and machinic orders; it helps provincialize the superpowers by casting problematic “other” natures as central and primary.


1994 ◽  
Vol 143 ◽  
pp. 159-171
Author(s):  
Ester Antonucci

The coronal features observed in X-ray emission, varying from the small-scale, short-lived bright points to the large-scale, long-lived coronal holes, are closely associated with the coronal magnetic field and its topology, and their variability depends strongly on the solar cycle. Here we discuss the spatial distribution of the coronal structures, the frequency distribution of the brightness variations in active regions, and the role of magnetic reconnection in determining the variability of the coronal features, on the basis of the new observations of the soft X-ray emission recently obtained with the Yohkoh satellite and the NIXT experiment.


Slavic Review ◽  
2012 ◽  
Vol 71 (1) ◽  
pp. 108-134 ◽  
Author(s):  
Madeleine Reeves

Drawing on ethnographic and survey data, Madeleine Reeves explores the meanings and impact of large-scale seasonal labor migration to Russia on a group of four kin-related villages in southern Kyrgyzstan. Although remittances have come to figure centrally in domestic budgets of migrant families, it is to questions of political economy that we must turn to understand the shift away from small-scale farming toward migrant work. Reeves examines a range of factors mediating decisions to migrate, including the role of social networks and sibling hierarchies; the emergence of growing economic differentials between migrant and nonmigrant households, and the growing importance for young men of a period of work “in town” (shaarda) in proving their eligibility for marriage. Although patterns of economic activity in southern Kyrgyzstan have changed dramatically in recent years, Reeves argues that new forms of engagement in distant labor markets are also being used to sustain patterns of ritual gifting and expressions of ethnic and religious identity that are imagined and articulated precisely as expressions of social continuity.


Author(s):  
Selin Çağatay ◽  
Mia Liinason ◽  
Olga Sasunkevich

AbstractThis chapter lays out the theoretical foundation of the book. It conceptualizes resistance as a space in-between small-scale mundane practices with a low level of collective organizing and large-scale protest activities which often exemplify resistance in social movement studies. In line with feminist and queer conceptualization of resistance, the authors suggest to examine multi-scalarity of resistant practices. The chapter attends to three scales of feminist and LGBTI+  activism in Russia, Turkey, and Scandinavia. The first scale analyzes activism in relation to the civil society-state-market triad. The second scale problematizes the notion of solidarity in relations between feminist and LGBTI+  activists from different geopolitical regions and countries as well as between small- and large-scale activist organizations and groups. Finally, the third scale focuses on individual resistant practices and the role of individual bodies in emergence of collective political struggles.


J-Dinamika ◽  
2018 ◽  
Vol 3 (2) ◽  
Author(s):  
Bambang Utoyo ◽  
Adryade Reshi Gusta ◽  
Yan Sukmawan ◽  
Made Same

Pepper is one of the spice crops that contribute to improving the Indonesian economy. Pepper cultivation is carried out on a small scale to a large scale. Pepper propagation by cutting is considered quite effective and efficient. Politeknik Negeri Lampung has been develop the Pepper Nursery Unit since 2007. This unit runs a business in the production of climbing pepper seedling, shrub pepper seedling, and pepper nursery training. The aim of this program is to support the mission of Politeknik Negeri Lampung in preparing itself to face college campus autonomy through the acquisition of revenue from established business units, accelerating the process of developing an entrepreneurial cultural system in the campus environment, providing competency development opportunities for staff and students, and increasing the role of the Politeknik Negeri Lampung for the community, especially in agriculture. The impact of this program is the availability of hight quality pepper seedling, increasing income generating Politeknik Negeri Lampung, establishment of the Pepper Nursery Unit and training service, improving the skills of Politeknik Negeri Lampung students in pepper nursery, developing entrepreneurial potential for students and staff, as well as increasing the role of Lampung State Polytechnic in community service activities.Keywords—Campus entrepreuneurship, estate crop, nursery business.


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