Coding and Compression of Three Dimensional Meshes by Planes

The present paper suggests a new approach for geometric representation of 3D spatial models and provides a new compression algorithm for 3D meshes, which is based on mathematical theory of convex geometry. In our approach we represent a 3D convex polyhedron by means of planes, containing only its faces. This allows not to consider topological aspects of the problem (connectivity information among vertices and edges) since by means of the planes we construct the polyhedron uniquely. Due to the fact that the topological data is ignored this representation provides high degree of compression. Also planes based representation provides a compression of geometrical data because most of the faces of the polyhedron are not triangles but polygons with more than three vertices.Comment: 10 pages, 7 figure

Identifying Integration Barriers for Repatriated Young People in Armenia

The problem of repatriation is not new in the Armenian reality. Repatriation, as a process coordinated by the state (through official policy), with its periodicity and massiveness, draws special attention especially in the Soviet period of the Armenian history (in particular, in the case of the wave named "Great Repatriation" in 1946-1948 (Stepanyan, 2020)). Later, in the post-Soviet realities, although repatriation processes continue, they differ from previously organized manifestations, which creates the need for new studies reinterpreting the phenomenon. Along with the historical observations which provide important analytical perspectives, it is important to consider the conceptual foundations of the phenomenon of repatriation from a methodological point of view. In particular, according to distinct dictionary definitions of repatriation, it is the return from exile to the homeland, the return of prisoners of war and civilian population who are outside the borders of their homeland to their homeland as a result of military operations (Aghayan, 1976). Nevertheless, refraining from private definitions of the phenomenon, we will rely on the most general modern interpretations of repatriation, according to which repatriation is the process of returning to the country of departure or the ethnic homeland (regardless of the fact that sometimes the country of departure is not considered a homeland after generations (Barseghyan, 2019)). Moreover, it is important to study repatriation not only from the point of view of opportunities, but also from the point of view of the complex problems of the integration nature following the process. Turning to integration as a social phenomenon, we have used the approaches of Bosswick and Heckmann, according to which social integration is the inclusion of the immigrant in the context of the institutional relations of the host country, as well as in the context of social roles and statuses. The authors consider social integration at four interrelated levels: structural, cultural, interactive, and self-identification. In particular, at the structural level, the necessary rights and opportunities provided for immigrants to participate in the host country's social statuses and basic institutions (such as the economy and labor market, the education system, civic participatory processes, housing services) are considered. At the cultural level, the authors emphasize the inclusion of the immigrant in the cultural experiences of the host country, in which the acquisition of communication skills (i.e. language skills) about the host country's culture is of special importance. The interactive aspect of integration, in turn, implies the incorporation of the immigrant into the area of social networks and relationships of the host society. At the level of self-identification, Bosswick and Heckmann consider the immigrant's perceptions of self-identification and belonging to social groups in the host country (Bosswick, Heckmann, 2006). Together with all of this, in the context of the integration issue, we have highlighted the experience of young repatriates, in which risks of integrative nature, with their possible negative impact, can lead to irreversible consequences. Thus, from the point of view of the socialization process, young people are seen as a key stage of human development, during which a person transitions from childhood to adulthood, or, in other words, from a state of dependence to a state of independence or interdependence. It is during youth that the individual creates foundations for the roles of maturity with their decisions (moral, social, economic, cultural, civil) (UNICEF, 2011). Moreover, the problems characteristic of this stage are even more pronounced in the conditions of the migration experience of young people, which is accompanied by unique risk factors. Their short-term and long-term negative manifestations can have irreversible harmful consequences in an individual's life. In particular, at the personal level, these problems can be expressed by the loss of the possibility of full human development, and at the societal level, they can be seen by the waste of the social, economic and cultural development potential of both sending and host countries (IOM Glossary on Migration, 2019). Thus, within the framework of this article, the results of the analysis of the research data are presented, based on which the main features of the factors that serve as obstacles in the integration processes of the repatriated young people are identified. The article presents the heterogeneity of the mentioned factors (structural-institutional, social, cultural, identity), providing a multifaceted view of the current manifestations of repatriation

THE NECESSITY OF INTRODUCTION THE DRUG INSURANCE SYSTEM IN ARMENIA

The increase in the cost of the medicinal component of the treatment, the spread of chronic diseases, and the maintenance of socio-economic inequality in access to health services require the provision of adequate access to medicines. These issues create prerequisites for the improvement of the state health policy and, first, the drug supply system, which is an integral part of the treatment process. The financing of healthcare in Armenia is mainly formed from budget allocations and out of pocket expenditures of the population. Reducing the financial burden on the state and ensuring the rational use of drugs contributes to improving the health of the population. The implementation of a drug insurance scheme, which partially or fully cover the cost of drugs in RA, is one of the solutions for resolving the issue of access to medicines. This article studies the problems of financing healthcare system in Armenia and highlights the need of introduction a drug insurance system in Armeni

Efficient characterisation of large deviations using population dynamics

We consider population dynamics as implemented by the cloning algorithm for analysis of large deviations of time-averaged quantities. We use the simple symmetric exclusion process with periodic boundary conditions as a prototypical example and investigate the convergence of the results with respect to the algorithmic parameters, focussing on the dynamical phase transition between homogeneous and inhomogeneous states, where convergence is relatively difficult to achieve. We discuss how the performance of the algorithm can be optimised, and how it can be efficiently exploited on parallel computing platforms

On the initiation of lightning in thunderclouds

The relationship of lightning and elementary particle fluxes in the thunderclouds is not fully understood to date. Using the particle beams (the so-called Thunderstorm Ground Enhancements-TGEs) as a probe we investigate the characteristics of the interrelated atmospheric processes. The well-known effect of the TGE dynamics is the abrupt termination of the particle flux by the lightning flash. With new precise electronics, we can see that particle flux decline occurred simultaneously with the rearranging of the charge centers in the cloud. The analysis of the TGE energy spectra before and after the lightning demonstrates that the high-energy part of the TGE energy spectra disappeared just after lightning. The decline of particle flux coincides on millisecond time scale with first atmospheric discharges and we can conclude that Relativistic Runaway Electron Avalanches (RREA) in the thundercloud assist initiation of the negative cloud to ground lightning. Thus, RREA can provide enough ionization to play a significant role in the unleashing of the lightning flash

Analyzing atmospheric electric field by the European SEVAN network of particle detectors

Particle detectors of the European SEVAN network located on mountain heights in Aragats (Armenia), Lomnický štít (Slovakia) and Musala (Bulgaria) are well suited for the detection of thunderstorm ground enhancements (TGEs, enhanced fluxes of electrons, gamma rays, neutrons). The modulation of charged particles flux by the electric field of the thundercloud results in a sizable change in the count rate of detectors, which measure fluxes of electrons, gamma rays, and high energy muons in the near-vertical and near-horizontal directions. The relation between electric field strength and changes of particle flux count rates is nonlinear and depends on many unknown parameters of atmospheric electric field and meteorological conditions. Nonetheless, employing extreme TGEs as a manifestation of the strong electric field in the thundercloud and by measuring fluxes of three species of secondary cosmic rays (electrons, gamma rays, and muons) by SEVAN detectors located at altitudes of ≈ 3 km we study the extreme strength of the atmospheric electric field. With the simulation of particle traversal through the electric field with CORSIKA code (https://www.iap.kit.edu/corsika/index.php, last accessed April 21, 2021), we derive a maximum potential difference in the thunderous atmosphere to be ≈ 500 MV

Integration of water, sanitation, and hygiene for the prevention and control of neglected tropical diseases: a rationale for inter-sectoral collaboration.

Improvements of water, sanitation, and hygiene (WASH) infrastructure and appropriate health-seeking behavior are necessary for achieving sustained control, elimination, or eradication of many neglected tropical diseases (NTDs). Indeed, the global strategies to fight NTDs include provision of WASH, but few programs have specific WASH targets and approaches. Collaboration between disease control programs and stakeholders in WASH is a critical next step. A group of stakeholders from the NTD control, child health, and WASH sectors convened in late 2012 to discuss opportunities for, and barriers to, collaboration. The group agreed on a common vision, namely "Disease-free communities that have adequate and equitable access to water and sanitation, and that practice good hygiene." Four key areas of collaboration were identified, including (i) advocacy, policy, and communication; (ii) capacity building and training; (iii) mapping, data collection, and monitoring; and (iv) research. We discuss strategic opportunities and ways forward for enhanced collaboration between the WASH and the NTD sectors

Three-factor mathematical model for determinig motor vehicle fuel consumption under operating mountain conditions

Various factors have an impact on fuel consumption during the operation of a motor vehicle. Among them, we can mention the nominal fuel consumption based on structural features and standard operating conditions of the motor vehicle as the primary reason, followed by additional costs of the fuel. The additional costs are due to changes in road surface conditions, an increase in the vehicle load, and the adaptability of the motor vehicle towards these. In other words, the increase in vehicle fuel consumption is explained by the deviation of operating conditions from standard values. This increase is particularly related to the level of vehicle adaptability. When operating in mountainous conditions, the indicated deviation is strongly related to the slope of the longitudinal profile of the road, as well as, to the geographic height of the terrain. In this paper, a three-factor mathematical model is developed which defines the relationship between the speed of the vehicle, the height of the terrain, and the slope of the road