1,833 research outputs found
PROBLEMS OF CALCULATION AND THE DESIGN OF BEARING STRUCTURES OF DIPLOMATIC BUILDINGS IN SEISMIC ZONES
In the results of researches carried out in the Peoples Friendship University of Russia, the main variants of structure systems and forms of diplomatic buildings in seismic zones are received
PROBLEMS OF ANALYSIS OF CONSTRUCTIONS OF DIPLOMATIC COMPLEXES
Some recommendations in calculation for structure elements according with new construction rules are proposed in the results of analyze of the experience design of the structure elements of diplomatic building
Radio Spectral Evolution of an X-ray Poor Impulsive Solar Flare: Implications for Plasma Heating and Electron Acceleration
We present radio and X-ray observations of an impulsive solar flare that was
moderately intense in microwaves, yet showed very meager EUV and X-ray
emission. The flare occurred on 2001 Oct 24 and was well-observed at radio
wavelengths by the Nobeyama Radioheliograph (NoRH), the Nobeyama Radio
Polarimeters (NoRP), and by the Owens Valley Solar Array (OVSA). It was also
observed in EUV and X-ray wavelength bands by the TRACE, GOES, and Yohkoh
satellites. We find that the impulsive onset of the radio emission is
progressively delayed with increasing frequency relative to the onset of hard
X-ray emission. In contrast, the time of flux density maximum is progressively
delayed with decreasing frequency. The decay phase is independent of radio
frequency. The simple source morphology and the excellent spectral coverage at
radio wavelengths allowed us to employ a nonlinear chi-squared minimization
scheme to fit the time series of radio spectra to a source model that accounts
for the observed radio emission in terms of gyrosynchrotron radiation from
MeV-energy electrons in a relatively dense thermal plasma. We discuss plasma
heating and electron acceleration in view of the parametric trends implied by
the model fitting. We suggest that stochastic acceleration likely plays a role
in accelerating the radio-emitting electrons.Comment: 22 pages, 10 figure
Consideration of climatic conditions in the design of dwellings in the Sahara desert
Climate is one of the important factors in architecture. The historical architecture experience of the inhabitants of the desert zones has created invaluable knowledge on the design of residential environments in these aggressive conditions. Climate also is an important ecological component in the formation of vernacular architecture in the Saharan desert, it had a strong influence on the formation of desert settlements, the Saharan traditional dwellings are an indispensable source for studying organizations and architectural typologies and the adaption to the harsh climate. The article discusses the climatic conditions in which the dwellings in the Sahara desert were built and the important strategies and passive climatization techniques of the design of the dwellings and presents a review of the various techniques developed. These various passive methods and strategies give the Saharan dwellings, adaptation, efficiency, and durability in these hot-arid conditions of the desert and can be a great source of architectural inspiration for new projects
THE STUDY OF BUSINESS CENTERS IN THE ARABIAN GULF: RESIDENTIAL, OFFICES, AND COMMERCIAL BUILDINGS
The modern architecture of the Arabian Gulf has become an international icon after the completion of Burj Al Arab in 1999. Since then, many more modern buildings were built in order to host the numerous international companies residing or branching in the Arabian Gulf especially in Dubai.This article will examine few examples of the modern architecture the Arabian Gulf, some of many amazing projects were constructed, alongside a brief introduction, what challenges the architecture faces in the Arabian Gulf, and what’s the future seems like
Quiescent Radio Emission from Southern Late-type M Dwarfs and a Spectacular Radio Flare from the M8 Dwarf DENIS 1048-3956
We report the results of a radio monitoring program conducted at the
Australia Telescope Compact Array to search for quiescent and flaring emission
from seven nearby Southern late-type M and L dwarfs. Two late-type M dwarfs,
the M7 V LHS 3003 and the M8 V DENIS 1048-3956, were detected in quiescent
emission at 4.80 GHz. The observed emission is consistent with optically thin
gyrosynchrotron emission from mildly relativistic (~1-10 keV) electrons with
source densities n_e ~ 10 G magnetic fields. DENIS
1048-3956 was also detected in two spectacular, short-lived flares, one at 4.80
GHz (peak f_nu = 6.0+/-0.8 mJy) and one at 8.64 GHz (peak f_nu = 29.6+/-1.0
mJy) approximately 10 minutes later. The high brightness temperature (T_B >~
10^13 K), short emission period (~4-5 minutes), high circular polarization
(~100%), and apparently narrow spectral bandwidth of these events imply a
coherent emission process in a region of high electron density (n_e ~
10^11-10^12 cm^-3) and magnetic field strength (B ~ 1 kG). If the two flare
events are related, the apparent frequency drift in the emission suggests that
the emitting source either moved into regions of higher electron or magnetic
flux density; or was compressed, e.g., by twisting field lines or gas motions.
The quiescent fluxes from the radio-emitting M dwarfs violate the Gudel-Benz
empirical radio/X-ray relations, confirming a trend previously noted by Berger
et al. (abridged)Comment: 28 pages, 8 figures, accepted for publication in Ap
Diapiric growth within an Early Jurassic rift basin: The Tazoult salt wall (central High Atlas, Morocco)
The central High Atlas (Morocco) constitutes a diapiric province that hosts a complex array of elongated diapirs and minibasins that formed during the Lower Jurassic rift of the Atlas Basin. This paper aims to study the structure and growth evolution of the Tazoult diapiric wall, located in the central High Atlas, by means of structural and sedimentological fieldwork integrated with remote sensing mapping. The Tazoult salt wall is a 20km long×3km wide NE-SW trending ridge that exposes Upper Triassic red beds and basalts along its core. The succession flanking the salt wall ranges from Hettangian to Bajocian ages displaying spectacular sedimentary wedges in the SE and NW flanks. The Hettangian-early Sinemurian carbonates mainly crop out as blocks embedded in the core rocks. The ~1km thick Pliensbachian platform carbonates display large subvertical flap structures along the flanks of the Tazoult salt wall with unconformities bounding tapered composite halokinetic sequences. In contrast, the ~2.5km thick late Pliensbachian-Aalenian mixed deposits form tabular composite halokinetic sequences displaying small-scale hook halokinetic sequences. Passive diapirism resulted in the lateral extrusion of the evaporite-bearing rocks to form an allochthonous salt sheet toward the adjacent SE Amezraï minibasin. The Bajocian platform carbonates partially fossilized the Tazoult salt wall and thus constitute a key horizon to constrain the timing of diapir growth and discriminate diapirism from Alpine shortening. The Pliensbachian carbonate platform evolved as a long flap structure during the early growth of the Tazoult salt wall, well before the onset of the Alpine shortening. © 2016. American Geophysical Union. All Rights Reserved.Additional funding was provided by the Spanish Ministry of Education and Science (MEC) through the projects Intramural Especial (CSIC 201330E030) and 201530E082), Atiza (CGL2009-1355), Tecla (CGL2011-26670), and the postdoctoral research contract to E.S. (CSIC-FSE 2007-2013 JAE-Doc), as well as by the Generalitat
de Catalunya (2014GSR251).Peer reviewe
The compositional and evolutionary logic of metabolism
Metabolism displays striking and robust regularities in the forms of
modularity and hierarchy, whose composition may be compactly described. This
renders metabolic architecture comprehensible as a system, and suggests the
order in which layers of that system emerged. Metabolism also serves as the
foundation in other hierarchies, at least up to cellular integration including
bioenergetics and molecular replication, and trophic ecology. The
recapitulation of patterns first seen in metabolism, in these higher levels,
suggests metabolism as a source of causation or constraint on many forms of
organization in the biosphere.
We identify as modules widely reused subsets of chemicals, reactions, or
functions, each with a conserved internal structure. At the small molecule
substrate level, module boundaries are generally associated with the most
complex reaction mechanisms and the most conserved enzymes. Cofactors form a
structurally and functionally distinctive control layer over the small-molecule
substrate. Complex cofactors are often used at module boundaries of the
substrate level, while simpler ones participate in widely used reactions.
Cofactor functions thus act as "keys" that incorporate classes of organic
reactions within biochemistry.
The same modules that organize the compositional diversity of metabolism are
argued to have governed long-term evolution. Early evolution of core
metabolism, especially carbon-fixation, appears to have required few
innovations among a small number of conserved modules, to produce adaptations
to simple biogeochemical changes of environment. We demonstrate these features
of metabolism at several levels of hierarchy, beginning with the small-molecule
substrate and network architecture, continuing with cofactors and key conserved
reactions, and culminating in the aggregation of multiple diverse physical and
biochemical processes in cells.Comment: 56 pages, 28 figure
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