20 research outputs found
Spatial structure of the temperature and salinity fields in the presence of internal waves on the continental shelf of the states of Jalisco and Colima (Mexico)
No full textA method to filter fluctuations in the hydrophysical properties of the continental shelf, caused by intense internal tides, is proposed. The method is based on a smoothing of the field of the properties analyzed with a filter, the parameters of which are determined by the shape of the spatial correlation function of the field pulsations. The filtering method was tested on data from a fast oceanographic survey, conducted in an area of the monitoring polygon of the waters around Barra de Navidad. The survey was conducted on 25 and 26 November 1995, with an undulating CTD. In one day, 86 vertical profiles of temperature and salinity were obtained from nine transects perpendicular to the coast (survey area of 100 x 25 km) to a depth of 100 m. The filtering algorithm of the internal waves is studied in detail. The field measurements present an analytical shape obtained from an equation in which the elements describe the components: low frequency, pulsating and related to daily behavior. The results of the analysis of the initial temperature and salinity fields with respect to homogeneity and isotropy are discussed, as well as the structural peculiarities of the estimates of the spatial correlation functions. It is observed that the temperature and salinity fields along the shelf, within the limits of the polygon scale, are neither homogenous nor isotropic. The correlation functions of the field pulsations analyzed are more clearly observed in the thermocline. The characteristic scales perpendicular to the coast are smaller than along it. Examples of smoothing the temperature and salinity fields in the thermocline are given
Air temperature fluctuations in Guadalajara, Mexico, from 1926 to 1994 in relation to urban growth
No full text
On the conditions of internal tide wave generation along the west coast of Mexico
No full textBaines' (1982) model was used to calculate the energy flux of the barotropic M2 waves to internal waves. Fluxes and amplitudes of the internal waves are shown to be not only dependent on the barotropic tide intensity but also on its arrival angle to the shelf, which changes greatly. By using the vertical distribution of the Brunt-Vaisala frequency in the region of study, the trajectories of the energy flux of the internal waves were calculated. Our results indicate optimum conditions for the generation of internal tides close to the Mexican Pacific coast. According to the linear model of internal waves, an estimation of the parameters of the semidiurnal internal tides close to the continental slope and on the shelf was made
Seasonal variability of the temperature and salinity fields in the coastal zone of the states of Jalisco and Colima, Mexico
No full textThe results of the analysis of data obtained from a series of oceanographic surveys conducted in an ecological monitoring polygon on the continental shelf off Jalisco and Colima (Mexico) are presented. The surveys were conducted monthly between 1995 and 1997 with an undulating CTD. In one day, up to 100 soundings were made at stations with a maximum depth of 150 m, in a spatial grid of points with an area of 50 x 15 km. The vertical profiles of temperature and salinity were obtained by averaging the data from the oceanographic surveys. It is shown that the vertical distributions and hydrophysical characteristics analyzed present a significant seasonal variability related to the annual variations of solar energy input and variability of evaporation, precipitation and coastal discharges in the study area. The seasonal oscillations cover a water layer greater than 100 m, but the subsurface layers of the coastal waters are observed with greater intensity. The mean profiles present a high statistical reliability, since the deformations caused by the internal waves were completely suppressed
Actual questions of contact interaction between police officers and minors with deviant behavior.
No full textIn the article are considered the main questions of organization of contact interaction between police officers and minors with deviant behavior. The author suggests recommendations for improving this process. The presence of sharp resistance to interaction on the part of minors, the ironic-manipulative style of communication, the closed contact and unpreparedness of the police officers themselves for such forms of interaction, requires not only the upgrading of police officers skills in solving operational problems, but also arming them with specially developed interpersonal contact technologies for each type of deviant behavior. A special case is the need to refine the algorithms based on the contact interaction technique. Filonov for cases of adolescents who detect any forms of suicidal (autoaggressive) manifestations.</jats:p
Antiferromagnetic order in hybrid electromagnetic metamaterials
No full textWe demonstrate experimentally a new type of order in optical magnetism resembling the staggered structure of spins in antiferromagnetic ordered materials. We study hybrid electromagnetic metasurfaces created by assembling hybrid meta-atoms formed by metallic split-ring resonators and dielectric particles with a high refractive index, both supporting optically-induced magnetic dipole resonances of different origin. Each pair (or 'metamolecule') is characterized by two interacting magnetic dipole moments with the distance-dependent magnetization resembling the spin exchange interaction in magnetic materials. By directly mapping the structure of the electromagnetic fields, we demonstrate experimentally that strong coupling between the optically-induced magnetic moments of different origin can flip the magnetisation orientation in a metamolecule creating an antiferromagnetic lattice of staggered optically-induced magnetic moments in hybrid metasurfaces.Published versio
P\'olya's conjecture for Euclidean balls
No full textThe celebrated P\'{o}lya's conjecture (1954) in spectral geometry states that
the eigenvalue counting functions of the Dirichlet and Neumann Laplacian on a
bounded Euclidean domain can be estimated from above and below, respectively,
by the leading term of Weyl's asymptotics. P\'{o}lya's conjecture is known to
be true for domains which tile Euclidean space, and, in addition, for some
special domains in higher dimensions. In this paper, we prove P\'{o}lya's
conjecture for the disk, making it the first non-tiling planar domain for which
the conjecture is verified. We also confirm P\'{o}lya's conjecture for
arbitrary planar sectors, and, in the Dirichlet case, for balls of any
dimension. Along the way, we develop the known links between the spectral
problems in the disk and certain lattice counting problems. A key novel
ingredient is the observation, made in recent work of the last named author,
that the corresponding eigenvalue and lattice counting functions are related
not only asymptotically, but in fact satisfy certain uniform bounds. Our proofs
are purely analytic, except for a rigorous computer-assisted argument needed to
cover the short interval of values of the spectral parameter in the case of the
Neumann problem in the disk.Comment: v.4: some corrections and presentation changes. 34 pages, six
figures, one tabl
Superdirective nanoantennas: Theory and experiment
No full textWe introduce a novel concept of superdirective nanoantennas based on the generation of higherorder optically-induced magnetic multipoles. Such an all-dielectric nanoantenna can be realized as an optically small spherical dielectric nanoparticle with a no
Image of Velimir Khlebnikov in "Chelokon" by Boris Viktorovpoba
No full textСтатья посвящена необычному мифологическому изображению Велимира Хлебникова в поэзии Бориса Викторова. Анализируя мотивы книги Викторова «Челоконь», автор предполагает, что образ Хлебникова в книге связан с образом вещего конеподобного зверя Китовраса из русских апокрифов XIV века, восходящих к талмудическим легендам. В статье показано, как у Викторова эти образы развиваются, отражаются друг в друге, и в конце-концов совмешаются в поэме “Китоврас”, завершающей книгу. В доказательство своей интерпретации образа Китовраса как мифологического изображения Хлебникова автор ссылается на портреты Хлебникова, изображающие его в виде коня/оленя (П. Филонов, П. Митурич), и часто повторяющийся фантастический образ коня в поэзии самого Хлебникова (Конь Пржевальского, Семеро).В статье сделан вывод, что, изображая Хлебникова в виде Китовраса, Викторов одновременно мифологизирует и деканонизирует поэта.The article focuses on the unusual depiction of Vелiмiр Khlebnikov via mythology in the poetry of Boris Viktorov. Through the analyses of the motifs in Viktorov’s collection of poems “Chelokon' ” the author suggests that a strong link exists between the image of Кhlebnikov and that of the mythological, prophetic, hors-like beast Kitovras from the apocryphal tale of the Old Testament. It is shown that these images move along parallel lines throughout the book, reflecting each other and eventually coalescing in the poema Kitovras which concludes the collection. To support the interpretation of the figure of Kitovras as a mythological representation of Khlebnikov, the author refers to artistic depictions of Khlebnikov which exposes his horse-like features (P. Filonov, P. Miturich) and to poems by Кhlebnikov which include the fantastic image of a horse (Kon’ Przheval’skogo, Semero).The author argues that the juxtaposition of the figures of Кhlebnikov and Kitovras is Viktorov’s attempt to simultaneously mythologize and de-canonize the poet
