Stream Formation Research Articles

Development of Realtime GRID Analysis Method based on the High Precision Streaming Data

With the recent advancement of surveying and technology, the spatial data acquisition rates and precision have been improved continually. As the updates of spatial data are rapid, and the size of data increases in line with the advancing technology, the LOD (Level of Detail) algorithm has been adopted to process data expressions in real time in a streaming format with spatial data divided precisely into separate steps. The existing GRID analysis utilizes the single DEM, as it is, in examining and analyzing all data outside the analysis area as well, which results in extending the analysis time in proportion to the quantity of data. Hence, this study suggests a method to reduce analysis time and data throughput by acquiring and analyzing DEM data necessary for GRID analysis in real time based on the area of analysis and the level of precision, specifically for streaming DEM data, which is utilized mostly for 3D geographic information service.

A Review of Infiltration Excess Overland Flow (IEOF): Terms, Models and Environmental Impact

High precipitation rate usually give an impact on soil instability and streamflow volume that lead to hazard such as landslide, soil erosion and flood. However, such hazard might happen as a result of various factors including types of soil, soil structure, land used, human activities and surface and subsurface water flow. The major changes on flow rate might change the soil structure and flow direction due to high volume of precipitation with uneven dispersion, especially in hilly topography. The research on Streamflow Generating Process (SGP) has been advancing in order to understand the formation of stream resulting from both surface and subsurface flow comprising Infiltration Excess Overland Flow (IEOF), Saturation Excess Overland Flow (SEOF), Shallow Subsurface Flow (SSF), Direct Precipitation onto Stream Surface (DPOSS), percolation, evapotranspiration and ground water (GW). This paper will only focus on one of the process which is IEOF. Despite the apparent important of IEOF in determining changes in environment, relatively little is understood in the processes that occurred behind. The review aims to minimize the misconception on the terms that regularly used in IEOF studies such as overland flow, surface runoff, urban runoff and stormwater. The term used can make the meaning become misleading and give confusion to the readers. A numerous of terms used to explain the process in Hydrology does not pose problems for Hydrologist but effect the understanding of those who are from different field of background. Besides, this study also discussed on the current model that used in IEOF studies and the trend of integrated hydrological and Geographic Information System (GIS) model in solving IEOF problems. In addition, this paper also concentrates on one of the environmental issues that give impact to IEOF which is global warming.

Расчет сжигания токсичного вещества с образованием вертикальной сверхзвуковой струи продуктов сгорания

A system for burning of a destroyed highly toxic substance with formation of a vertical supersonic stream of combustion products moved away to the atmosphere on considerable heights has been considered. A technique and an algorithm for conjugated gas-dynamic and thermodynamic calculation of working processes in two-zonal unit with primary burning using air in a camera similar to the one of a liquid rocket engine, and after-burning in a supersonic flow have been proposed. The technique has been approved on the examples of after-burning mathematical modeling and a parametrical research on combustion completeness influence on composition and properties of products resulting from heptyl combustion in air with after-burning in case of methane supply in the second zone.

The C-Terminal SynMuv/DdDUF926 Domain Regulates the Function of the N-Terminal Domain of DdNKAP.

NKAP (NF-κB activating protein) is a highly conserved SR (serine/arginine-rich) protein involved in transcriptional control and splicing in mammals. We identified DdNKAP, the Dictyostelium discoideum ortholog of mammalian NKAP, as interacting partner of the nuclear envelope protein SUN-1. DdNKAP harbors a number of basic RDR/RDRS repeats in its N-terminal domain and the SynMuv/DUF926 domain at its C-terminus. We describe a novel and direct interaction between DdNKAP and Prp19 (Pre mRNA processing factor 19) which might be relevant for the observed DdNKAP ubiquitination. Genome wide analysis using cross-linking immunoprecipitation-high-throughput sequencing (CLIP-seq) revealed DdNKAP association with intergenic regions, exons, introns and non-coding RNAs. Ectopic expression of DdNKAP and its domains affects several developmental aspects like stream formation, aggregation, and chemotaxis. We conclude that DdNKAP is a multifunctional protein, which might influence Dictyostelium development through its interaction with RNA and RNA binding proteins. Mutants overexpressing full length DdNKAP and the N-terminal domain alone (DdN-NKAP) showed opposite phenotypes in development and opposite expression profiles of several genes and rRNAs. The observed interaction between DdN-NKAP and the DdDUF926 domain indicates that the DdDUF926 domain acts as negative regulator of the N-terminus.

GEOLOGICAL STRUCTURE AND MORPHOGENESIS OF THE ELBLĄG ELEVATION IN THE LIGHT OF DIVERSIFIED DYNAMICS OF the VISTULian ICE SHEET

Glaciotectonic and neotectonic processes are among the key factors influencing the geological structure of the Elbląg Elevation. The former is undoubtedly interrelated with the latter. Intensity and scale of glaciotectonic processes were for the first time examined from the point of view of transgression dynamics of the Vistulian continental glaciers, advancing from the Baltic Sea area. Geological structure, morphology and bathymetry of the eastern part of the Central Baltic Sea bottom show that main elements of the dynamics were shaped in this area. The diversified dynamics resulted in the formation of ice streams, carrying the major part of ice mass out of the ice sheet. It also caused that the advance of the ice sheet over the Polish Lowlands was not synchronous and occurred with various intensity. The Elbląg Elevation was subjected to these rules, because it was the first to be situated within the diverse force of interaction field with ice stream B3 (streams according to Punkari, 1997), advancing towards the Polish Lowlands from the area of a submeridional megadepression of the Gotland Deep and the Gdańsk Deep (south-eastern part of Central Baltic Sea). As regards the Elbląg Elevation area, an evaluation of the scale and intensity of glaciotectonic processes in time has been performed. Especially strong glaciotectonic disturbances, appearing on the western slope of this elevation, have been related to the presence of the distinct, submeridionally oriented fault zone Iława–Elbląg (its northern part), which coincides with the western boundary of this elevation. The likely reason for the development of glaciotectonic deformation during the middle and upper parts of the Vistula Glaciation might habve been the change of the regime of neotectonic stress field, operating within the broad foreland of the Kuyavian-Pomeranian Swell, which probably took place at the end of the Eemian Interglacial.

Ionospheric electron density perturbations during the 7–10 March 2012 geomagnetic storm period

From 7 to 10 March 2012 a series of magnetospheric disturbances caused perturbations in the ionospheric electron density. Analyzing the interplanetary causes in each phase of this disturbed period, in comparison with the total electron content (TEC) disturbances, we have concluded that the interplanetary solar wind controls largely the ionospheric response. An interplanetary shock detected at 0328UT on 7 March caused the formation of prompt penetrating electric fields in the dayside that transported plasma from the near-equatorial region to higher in attitudes and latitudes forming a giant plasma fountain which is part of the so-called dayside ionospheric super-fountain. The super-fountain produces an increase in TEC which is the dominant effect at middle latitude, masking the effect of the negative storm. Simultaneously, inspecting the TEC maps, we found evidence for a turbulence in TEC propagating southward probably caused by large scale travelling ionospheric disturbances (LSTIDs) linked to auroral electrojet intensification. On 8 March, a magnetospheric sudden impulse at 1130UT accompanied with strong pulsations in all interplanetary magnetic field (IMF) components and with northward Bz component during the growth phase of the storm. These conditions triggered a pronounced directly driven substorm phase during which we observe LSTID. However, the analysis of DMSP satellite observations, provided with strong evidence for Sub-Auroral Polarization Streams (SAPS) formation that erode travelling ionospheric disturbances (TID) signatures. The overall result of these mechanisms can be detected in maps of de-trended TEC, but it is difficult to identify separately each of the sources of the observed perturbations, i.e. auroral electrojet activity and LSTIDs, super-fountain and SAPS.In order to assess the capability of the ionospheric profiler called Topside Sounder Model - assisted Digisonde (TaD model) to detect such perturbations in the electron density, electron density disturbances at heights from 200 to 1000km have been calculated with the TaD model and compared with slant TEC parameters obtained from GPS receivers co-located with the Digisondes whose data were used to generate the TaD model predictions. The model matches in qualitative terms the GPS TEC observed perturbations independently from the source. The physical mechanisms that govern the ionosphere, such as ion drag by neutral winds along magnetic field lines, E×B drifts, and increased recombination due to the neutral composition changes, offer various combinations of foF2, hmF2 and TEC variations, which TaD resolves. Counterwise, TaD can help the interpretation of various physical scenarios which cannot be achieved if solely TEC or F layer variations are considered.

Diseño e implementación de los instrumentos de recolección de la Encuesta Nacional de Salud Mental Colombia 2015

IntroductionPopulation surveys on mental health are performed as part of the inputs required for the creation, implementation and evaluation of policies related to mental health, worldwide, and as an initiative of the World Health Organisation (WHO). was held The fourth National Survey of Mental Health (ENSM 2015) was carried out during the first half of 2015 on a representative sample of 2,727 children between 7 and 11 years of age, 1,754 adolescents, and 10, 870 adults who were selected throughout the country. ObjectiveTo describe the selection and definition of the tools used to measure mental health (including social cognition and violence), problems, mental disorders, and the evaluation of health states, as well as to describe the process used to develop the data collection tools finally used. ResultsThe measurement of mental disorders in children was performed using the Diagnostic Interview Schedule for Children (DISC), and the Composite International Diagnostic Interview (CIDI) was used for adolescents and adults. For the remaining components evaluated in the survey, a search was conducted on the tools used at a national and international level. The selection of the toos used for the evaluation was based on the questions made by each tool, as well as the scientific validity that could be obtained from the results. In some cases the complete tool (as published) was used, in other cases the tools were constructed unifying parts of different ones, or questions were written based on the concepts or characteristics to be measured. Subsequently, a validation of content, concept and semantic of every tool was carried out, including the CIDI and DISC. The resulting tools were used on a group of people with different characteristics. It was noted that further clarification was necessary for some people to fully understand what was being asked. Because the collection of all the information in the survey would be computer assisted, a stream format was generated to guide the implementation in Blaise software, after the creation and wording of each tool in order to review the validation process of the survey and to ensure the integrity in the order of questions and their format. Fictitious cases were generated during the process, and volunteers participated in the testing. ConclusionsThe tools for information collection used in the National Survey of Mental Health 2015 are presented.

Structure of currents in the soliton of an internal wave

The characteristics of strongly nonlinear solitary internal waves (solitons), which are calculated by the nonlinear numerical model of the Massachusetts Institute of Technology (MITgcm), are studied. The model is verified and adopted on the basis of a laboratory experiment [6]. The field of the vertical and horizontal current in a wave is calculated. The formation of a reversible stream in the near-bottom layer is detected directly behind a soliton.

Psychological ownership and music streaming consumption

Streaming is becoming the most common format from which people access, share and listen to music and it is suggested that such practices are indicative of a shift towards a ‘post-ownership’ economy. In the case of music, consumers may place greater value (emotional and monetary) on the physical product because of the lack of legal ownership and/or absence of perceived ownership associated with streaming. This article examines how experiences of ownership are articulated through music streaming formats via qualitative interviews and an online themed discussion group. Drawing from psychological ownership theory we identify motivations (place, identity and control), antecedents (investing the self, coming to intimately know the target, pride and controlling the target) and outcomes (loyalty, empowerment and social rewards) of psychological ownership that are evident in the consumers' experiences of music streaming. This has theoretical and managerial implications for our understanding of how consumers engage with the post-ownership economy.

Formation of the Andromeda giant stream: asymmetric structure and disc progenitor

We focus on the evidence of a past minor merger discovered in the halo of the Andromeda galaxy (M31). Previous N-body studies have enjoyed moderate success in producing the observed giant stellar stream (GSS) and stellar shells in M31's halo. The observed distribution of stars in the halo of M31 shows an asymmetric surface brightness profile across the GSS; however, the effect of the morphology of the progenitor galaxy on the internal structure of the GSS requires further investigation in theoretical studies. To investigate the physical connection between the characteristic surface brightness in the GSS and the morphology of the progenitor dwarf galaxy, we systematically vary the thickness, rotation velocity and initial inclination of the disc dwarf galaxy in N-body simulations. The formation of the observed structures appears to be dominated by the progenitor's rotation. Besides reproducing the observed GSS and two shells in detail, we predict additional structures for further observations. We predict the detectability of the progenitor's stellar core in the phase-space density distribution, azimuthal metallicity gradient of the western shell-like structure and an additional extended shell in the north-western direction that may constrain the properties of the progenitor galaxy.

Neural correlates of attention and streaming in a perceptually multistable auditory illusion

In a complex acoustic environment, acoustic cues and attention interact in the formation of streams within the auditory scene. In this study, a variant of the "octave illusion" [Deutsch (1974). Nature 251, 307-309] was used to investigate the neural correlates of auditory streaming, and to elucidate the effects of attention on the interaction between sequential and concurrent sound segregation in humans. By directing subjects' attention to different frequencies and ears, it was possible to elicit several different illusory percepts with the identical stimulus. The first experiment tested the hypothesis that the illusion depends on the ability of listeners to perceptually stream the target tones from within the alternating sound sequences. In the second experiment, concurrent psychophysical measures and electroencephalography recordings provided neural correlates of the various percepts elicited by the multistable stimulus. The results show that the perception and neural correlates of the auditory illusion can be manipulated robustly by attentional focus and that the illusion is constrained in much the same way as auditory stream segregation, suggesting common underlying mechanisms.

The Design and Performance Analysis of DTMB System

Various standard in digital television broadcasting system has been developed in the world, one of which is the Digital Terrestrial Multimedia Broadcasting, or abbreviated as DTMB that currently used by China and Hong Kong. DTMB has several standard configurations and parameters. In this research, DTMB system was designed and the results was validated through simulation using computer program, named Simulink. The parameters used in this research is the FEC with code rate of 0.4, 4QAM modulation, interleaver mode 1 and using a single carrier transmission mode. Stream format used in the simulation was MPEG2-TS as the input for DTMB system. Parameters selection was based on low implementation complexity, but with good results. Two important things in DTMB system is the existence of FEC and TDS-OFDM. FEC consists of cascaded BCH as the outer encoder/decoder (codec) and LDPC as the inner codec. The reason of using TDS-OFDM because it provides better picture quality when the receiver is in motion. The test results have shown that for static video, DTMB was able to receive video with identical quality compared to the original video, when the value of SNR=11dB and SNR=12dB for dynamic video. It is shown that after going through the process from LDPC to BCH, the number of bit errors decreased while the value of SNR increased.

The role of ice stream dynamics in deglaciation

AbstractSince the mid‐Pleistocene transition, deglaciation has occurred only after ice sheets have grown large while experiencing several precession and obliquity cycles, indicating that large ice sheets are more sensitive to Milankovitch forcing than small ice sheets are. Observations and model simulations suggest that the development of ice streams in the Laurentide Ice Sheet played an as yet unknown role in deglaciations. In this study, we propose a mechanism by which ice streams may enhance deglaciation and render large ice sheets more sensitive to Milankovitch forcing. We use an idealized configuration of the Parallel Ice Sheet Model that permits the formation of ice streams. When the ice sheet is large and ice streams are sufficiently developed, an upward shift in equilibrium line altitude, commensurate with Milankovitch forcing, results in rapid deglaciation, while the same shift applied to an ice sheet without fully formed ice streams results in continued ice sheet growth or slower deglaciation. Rapid deglaciation in ice sheets with significant streaming behavior is caused by ice stream acceleration and the attendant enhancement of calving and surface melting at low elevations. Ice stream acceleration is ultimately the result of steepening of the ice surface and increased driving stresses in ice stream onset zones, which come about due to the dependence of surface mass balance on elevation. These ice sheet simulations match the broad features of geomorphological observations and add ice stream dynamics that are missing from previous model studies of deglaciation.

Evaporation rate based water cycle algorithm for the environmental economic scheduling of hydrothermal energy systems

The environmental concerns are gaining importance nowadays for power producing companies in the context of clean energy act. The efforts of reducing the harmful emissions beyond a certain level are being made by most of the power utilities in the developing countries. Consequently, the minimization of harmful emissions has also become an important objective function while solving the hydrothermal scheduling problem. The heuristic approaches are considered as potential solution methodologies for non-convex hydrothermal scheduling. This paper presents an Evaporation Rate based Water Cycle Algorithm (ERWCA) for the solution of non-convex Environmental Economic Scheduling of Hydrothermal Energy Systems (EESHES). This algorithm has been evolved from the water cycle nature of raining, formation of streams, and their movement towards the rivers and finally into the sea. ERWCA has been investigated on the standard test system of EESHES with three case studies: (i) Economic Cost Scheduling, (ii) Environmental Economic Scheduling, (iii) Economic Environmental and Cost Scheduling. The comparison of obtained results with the recent results in the literature shows the superiority of ERWCA in terms of both lower fuel cost and fuel emissions. Hence, ERWCA is a worthwhile addition to the algorithms which have successfully solved this complex and combinatorial bi-objective optimization problem.

SPENDING TOO MUCH TIME AT THE GALACTIC BAR: CHAOTIC FANNING OF THE OPHIUCHUS STREAM

ABSTRACT The Ophiuchus stellar stream is peculiar: (1) its length is short given the age of its constituent stars, and (2) several probable member stars have dispersions in sky position and velocity that far exceed those seen within the stream. The stream’s proximity to the Galactic center suggests that its dynamical history is significantly influenced by the Galactic bar. We explore this hypothesis with models of stream formation along orbits consistent with Ophiuchus’ properties in a Milky Way potential model that includes a rotating bar. In all choices for the rotation parameters of the bar, orbits fit to the stream are strongly chaotic. Mock streams generated along these orbits qualitatively match the observed properties of the stream: because of chaos, stars stripped early generally form low-density, high-dispersion “fans” leaving only the most recently disrupted material detectable as a strong over-density. Our models predict that there should be a significant amount of low-surface-brightness tidal debris around the stream with a complex phase-space morphology. The existence of or lack of these features could provide interesting constraints on the Milky Way bar and would rule out formation scenarios for the stream. This is the first time that chaos has been used to explain the properties of a stellar stream and is the first demonstration of the dynamical importance of chaos in the Galactic halo. The existence of long, thin streams around the Milky Way, presumably formed along non- or weakly chaotic orbits, may represent only a subset of the total population of disrupted satellites.

SELECTING M GIANTS WITH INFRARED PHOTOMETRY: DISTANCES, METALLICITIES, AND THE SAGITTARIUS STREAM

ABSTRACT Using a spectroscopically confirmed sample of M giants, M dwarfs, and quasars from the LAMOST survey, we assess how well Wide-field Infrared Survey Explorer (WISE) and Two Micron All Sky Survey color cuts can be used to select M giant stars. The WISE bands are very efficient at separating M giants from M dwarfs, and we present a simple classification that can produce a clean and relatively complete sample of M giants. We derive a new photometric relation to estimate the metallicity for M giants, calibrated using data from the APOGEE survey. We find a strong correlation between the color and , where almost all of the scatter is due to photometric uncertainties. We show that previous photometric distance relations, which are mostly based on stellar models, may be biased and devise a new empirical distance relation, investigating trends with metallicity and star formation history. Given these relations, we investigate the properties of M giants in the Sagittarius stream. The offset in the orbital plane between the leading and trailing tails is reproduced, and by identifying distant M giants in the direction of the Galactic anticenter, we confirm that the previously detected debris in the outer halo is the apocenter of the trailing tail. We also find tentative evidence supporting an existing overdensity near the leading tail in the northern Galactic hemisphere, possibly an extension to the trailing tail (so-called Branch C). We have measured the metallicity distribution along the stream, finding a clear metallicity offset between the leading and trailing tails, in agreement with models for the stream formation. We include an online table of M giants to facilitate further studies.

The impact of floodplain land use on flood wave propagation

Due to their retention capacity, extensive flat floodplains have a significant impact on the propagation and transformation of flood waves. The conveyance and retention capacity of an area is significantly influenced by land use. The paper presents results of a hydraulic analysis of the impact of land use on the run-off regime in a retention area and consequently on flood wave propagation. The land use of the retention area was simulated by hydraulic roughness. The simulations were performed for flood waves with different values of peak discharge and with two lengths of duration. A spectrum of flood waves in which the retention areas have significant impact on the propagation was considered. To isolate the impact of topographical characteristics of riparian and retention areas on the communication of water between the channel and retention area, as well as on the formation of parallel streams in the area, a theoretical modelling area with simplified geometry was used in the first phase. Conclusions based on the results of the first-phase simulations were tested on a practical case of the plain Krsko–Brežisko polje, where data from field measurements as well as data from the physical model were used in the numerical calibration of the model.

Distribution and modes of occurrence of Au, Ag, and associated elements in the sediment streams of Au–Ag zones at the Dukat deposit (northeastern Russia)

We studied the distribution and modes of occurrence of the main (Au and Ag) and major associated elements indicating mineralization (Hg, Sb, As, Pb, Zn, and Cu) in samples of loose sediments from lithochemical sediment streams of Au–Ag zones at the Dukat deposit. The major mineral and nonmineral modes of occurrence of elements indicating Au–Ag mineralization have been detected with POLAM-312 and POLAR-3 ore microscopes and by X-ray electron probe microanalysis with JCXA-733 and JXA-8200 (JEOL, Japan) microprobes. The distribution and modes of occurrence of ore elements in the loose (alluvial) sediments of streams draining the Au–Ag zones are closely related to the ore composition. As in the ores, the main elements indicating mineralization are Au and Ag, while the major associated elements are Hg, Sb, As, Cu, Pb, and Zn. Gold in alluvial sediments occurs as electrum, fine (dispersed, ultradispersed, and colloid–dispersed) particles, and the so-called “bound” (predominantly with sulfides) invisible Au (sorption component and its derivates). Silver occurs not only as hypergene forms, microinclusions, and ultrasized particles but also in native form and as partly preserved sulfides and sulfosalts. The other elements (Hg, Sb, As, Pb, Zn, and Cu) are observed as secondary minerals of complex composition and differently preserved corroded fragments of pyrite, chalcopyrite, galena, and sphalerite grains, dominated by oxides and hydroxides (mainly those of iron). Salts and water-soluble sulfates of Fe, Cu, Pb, and Zn are less widespread. In study of the conditions of sediment stream formation in cryolithogenesis zones, where physical weathering is regarded as the major process, chemical factors (first of all, chemisorption) should also be taken into account. This is proven by the enrichment of “fine” loose material in Au, Ag, and ore elements in general. The high percentage of mobile forms of elements, which are easily leached out by ordinary acids, in ores and aureoles, together with the widespread occurrence of clay minerals and hydroxides, has a significant influence on chemisorption. For example, the portion of fine and “bound” Au, the element considered to be the least prone to chemical weathering, reaches 50–60% in the riverbed sediments of the stream head. Native Au (electrum) makes up 40–50%. The material is diluted during its transport. As Au content decreases, the portion of fine and “bound” Au in the sediment stream increases to 95%. Evidently, these two Au forms are predominant in streams as compared with ores. The modes of occurrence of elements indicating Au–Ag mineralization in secondary environments, as in primary ones, serve as an effective criterion for assessment of the potential of geochemical anomalies detected in sediment streams. They are a reliable indicator of ore associations, which is of practical significance. We think that modes of occurrence can sometimes be used to estimate the erosion level of drained zones and sites (i.e., to predict mineralization to depth). This criterion can be successfully applied at all stages of geochemical study of ore-bearing areas, from the prediction of the potential of anomalies detected in sediment streams in poorly studied areas to the detailed exploration of known ore objects.

THE PHOENIX STREAM: A COLD STREAM IN THE SOUTHERN HEMISPHERE

ABSTRACT We report the discovery of a stellar stream in the Dark Energy Survey Year 1 (Y1A1) data. The discovery was made through simple color–magnitude filters and visual inspection of the Y1A1 data. We refer to this new object as the Phoenix stream, after its resident constellation. After subtraction of the background stellar population we detect a clear signal of a simple stellar population. By fitting the ridge line of the stream in color–magnitude space, we find that a stellar population with age τ = 11.5 ± 0.5 Gyr and [Fe/H] < −1.6, located 17.5 ± 0.9 kpc from the Sun, gives an adequate description of the stream stellar population. The stream is detected over an extension of 8.°1 (2.5 kpc) and has a width of ∼54 pc assuming a Gaussian profile, indicating that a globular cluster (GC) is a probable progenitor. There is no known GC within 5 kpc that is compatible with being the progenitor of the stream, assuming that the stream traces its orbit. We examined overdensities (ODs) along the stream, however, no obvious counterpart-bound stellar system is visible in the coadded images. We also find ODs along the stream that appear to be symmetrically distributed—consistent with the epicyclic OD scenario for the formation of cold streams—as well as a misalignment between the northern and southern part of stream. Despite the close proximity we find no evidence that this stream and the halo cluster NGC 1261 have a common accretion origin linked to the recently found EriPhe OD.

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