Empirical Studies Applied to Software Process Models

Working Group Report: ICSE'99 Workshop on Empirical Studies of Software Development and Evolutio

Example of shock wave in unstaible medium: The focusing nonlinear Schrodinger equation

Dissipationless shock waves in modulational unstable one-dimensional medium are investigated on the simplest example of integrable focusing nonlinear Schr\''odinger (NS) equation. Our approach is based on the construction of special exact solution of the Whitham-NS system, which ''partially saturates'' the modulational instability.Comment: 4 pages, LaTEX, version 2.09, submitted to Phys. Lett.

FISH, cephalopods and associated habitats of the Discovery rise seamounts, Southeast Atlantic

In February 2019, seamounts of the Discovery Rise, SE Atlantic (41–45°S, 3°W - 3°E), were explored in support of the application of the Ecosystem Approach to Fisheries Management in the Southeast Atlantic Fisheries Organization (SEAFO) Convention Area. Video records of the seafloor were produced by the Video-Assisted Multisampler System (VAMS) along 15 valid transects conducted in plateau and flank areas of Shannon, Tablemount, Discovery and Heardman seamounts at depths ranging from 394 to 1839 m. Nine benthic seascapes were classified and described based on substrate hardness, texture, slope, physical and biological modifiers as observed in the video images. Predominant water masses were estimated from temperature, salinity and dissolved oxygen vertical profiles obtained by CTD casts in the vicinity of each transect. A total of 366 fishes were seen (total observation time = 25.0 h) and classified in 32 morphotypes, included in 9 orders and 12 families. Most fish morphotypes (14) were included in the Macrouridae family. Family Moridae, on the other hand, included 65.3% of all fish records (239), with two particularly abundant morphotypes: Laemonema sp. (116) and Guttigadus sp. (92). Thirteen cephalopods were observed and classified in five morphotypes; the oegopsid squid Moroteuthopsis ingens was the most abundant of them (6). Despite the taxonomic uncertainties associated with video identifications, the explored region was found to contain a mixture of tropical – subtropical and subantarctic faunas of the Atlantic. Similarities of fauna composition and non-directional beta diversity estimates revealed some degree of seamount identity, but 57.5–61.9% of morphotypes were shared among seamounts (Jaccard = 0.425, Sørensen = 0.381). Fishes and cephalopods were more frequently observed on the shallower plateau areas under the influence of warmer and more oxygenated Antarctic Intermediate Waters. Depth and related factors did not influence richness, but dissimilarities in fauna composition between video transects increased with increasing depth intervals. Spatial habitat heterogeneity may have accounted for the increased beta diversity within seamounts. The most widely explored Tablemount seamount contained the most diverse observed sites, but also a considerable spatial variability likely associated with seascape heterogeneity. In two sites (transects 11 and 14), there were exceptionally high aggregations of the morid cods Laemonema sp., at the shallowest ‘gravely’ site explored (397 m), and Guttigadus sp., at a site of intermediate depth (1020 m) covered mostly by soft sediments. Neither of these species (or congenerics) have been previously classified as ‘seamount-aggregating” species. On the other hand, the Patagonian toothfish (Dissostichus eleginoides) and other commercial species known to aggregate in these seamounts were not found in the explored areas.En prens

NATIONAL SELF-CONSCIOUSNESS OF STUDENTS IN HIGHER EDUCATIONAL STUDIES IN THE REPUBLIC OF TATARSTAN BY MEANS OF HUMANITARIAN DISCIPLINES

Purpose: The article describes the view of the author to the actualization of national consciousness of students by means of humanitarian disciplines. The processes of globalization and integration of Tatarstan Republic into the world space exacerbate the problem of preserving the uniqueness and identity, national cultures in the conditions of cultural diversity. Methodology: To solve the problems, we used the following research methods: theoretical (study and analysis of philosophical, psychological, ethnological, sociological, pedagogical, cultural, linguistic, methodological and other literature on the research topic); empirical (pedagogical observation, group and individual conversations, oral and written surveys, testing, questioning, pedagogical experiment); mathematical methods (registration of obtained data, method of mathematical processing of experimental research results). Result: The analysis of the research showed that developed national self-consciousness promotes spiritual development and self-development of the individual. National self-consciousness is the recognition of belonging to a certain national community, along with a positive assessment of representatives of other national cultures, the individual's representation of language, culture, typical features of the community, the common historical past, religion, territory, and statehood. Applications: This research can be used for the universities, teachers, and students. Novelty/Originality: In this research, the model of National Self-Consciousness of Students in Higher Educational Studies in the Republic of Tatarstan by Means of Humanitarian Disciplines is presented in a comprehensive and complete manner

Nonlinear optical dynamics of 2D super-crystals of quantum Λ-emitters

We study theoretically the optical response of a 2D super-crystal of quantum Λ-emitters which are coupled by their secondary dipole field. The latter introduces a feedback into the system, the interplay of which with the intrinsic nonlinearity of emitters results in an exotic behavior of the system's optical response, such as periodic or quasi-periodic self-oscillations and chaotic dynamics. We argue therefore that these predicted features can be promising for various nanophotonic applications

Nonlinear optical dynamics of two-dimensional super-lattices of quantum V-emitters

We study theoretically the nonlinear optical response of a super-lattice of regularly arranged three-level identical quantum emitters with a doublet in the excited state to the action of a monochromatic electromagnetic field quasi-resonant to optical transitions in the emitter, using into account the dephasing of the system. The total retarded dipole-dipole interaction of the emitters is accounted for in the mean-field approximation. This interaction plays the role of positive feedback, which (in combination with the immanent nonlinearity of emitters themselves) leads to multistability of the super-lattice response. The stability of different response branches is analyzed using the Lyapunov exponents' method. Another important property of the super-lattice is its high reflectance in a certain frequency range; i.e., within this range, the super-lattice operates as a perfect nanometer mirror; moreover, reflection can be switched to transmission changing slightly the incident field amplitude (bistability). The possibility of the application of the above-mentioned super-lattice optical properties in nanophotonics is discussed

Quantum metasurfaces of arrays of Λ-emitters for photonic nano-devices

We address exotic optical response of a planar metasurface comprising a monolayer of regularly spaced quantum three-level emitters with a doublet in the ground state (the so-called Λ-emitters). All emitters are coupled by the retarded dipole field which depends on the current state of all emitters. This coupling introduces a feedback into the system. Complex interplay of the latter with the intrinsic nonlinearity of a three-level system results in several remarkable effects in the monolayer's optical response, such as multistability, self-oscillations, and chaos. The peculiarity of the considered system is that some of the predicted nonlinear effects manifest themselves at very low excitation field intensities (on the order of 1 W/cm2), which is advantageous for possible applications: the monolayer can operate as a perfect reflector, a bistable mirror, and a THz or noise generator. It is argued therefore that the proposed system is a promising candidate for a building block for various photonic nano-devices