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41.
Gustavo Adolfo García‐Chapeton Frank Olaf Ostermann Rolf A. de By Menno‐Jan Kraak 《Transactions in GIS》2018,22(3):640-663
Collaboration across disciplines is recognized as one of the great challenges for research in visual analysis of geographic information (GeoVisual Analytics, GVA). Considering the increasing availability of geodata and the complexity of analytical problems, the need to advance the support for collaborative work is becoming more pressing and prominent. This article contributes to this objective by reviewing the state‐of‐the‐art of the support for collaborative work in GVA systems and by identifying research challenges and proposing strategies to address them. We conducted a systematic review, resulting in the identification of 13 collaborative systems, 6 distinct collaborative techniques, and 3 research challenges. We conclude that GVA is moving toward more effective support of multidisciplinary and cross‐domain collaborative analysis. However, to materialize this potential, research is needed to improve the support for hybrid collaborative scenarios, cross‐device collaboration, and support for time‐critical and long‐term analysis. 相似文献
42.
Marta M. Cassiano Pierre Kaufmann Rogério Marcon Amauri S. Kudaka Adolfo Marun Rodolfo Godoy Pablo Pereyra Arline M. Melo Hugo Levato 《Solar physics》2010,264(1):71-79
Solar observations in the mid-infrared 8 – 14 μm band continuum were carried out with cadence of 5 frames per second, in December 2007.
Rapid small heated sources, with a typical duration of the order of seconds, were found on the bright plage-like areas around
sunspots, in association with relatively weak GOES soft X-ray bursts. This work presents the analysis of fast mid-infrared
flashes detected during a GOES B2.0-class event on 10 December 2007, beginning at about 10:40 UT. Rapid brightness temperature
enhancements of 0.5 to 2.0 K were detected at the Earth by a microbolometer array, using a telescope with 10.5 cm diameter
aperture producing a diffraction-limited photometric beam of 25 arc sec. The minimum detectable temperature change was of
0.1 K. The corresponding fluxes are 30 – 130 solar flux units. At the solar surface the estimated rapid brightenings represented
a temperature enhancement of 50 – 150 K. 相似文献
43.
The distribution and composition of four benthic foraminifera assemblages from the Guaymas Basin are depicted through Q- and R-mode Factor Analysis. One of these assemblages is distributed near hydrothermal vents,* another developed away from the influence of the vents, and the other two assemblages are found in the subbottom sediments.Biostratigraphic analysis of five cores collected within the hydrothermal region suggest that the foraminiferal remains have been affected by aselective dissolution process. Only small species, such asBulimina spinosa andBolivina sp 2, have been preserved in the subbottom sediments which have been influenced by the hydrothermal activity. 相似文献
44.
Hernando Tavera Efraín Fernández Isabel Bernal Yanet Antayhua Consuelo Agüero Henry Salas Simeón Rodríguez Luis Vilcapoma Yolanda Zamudio David Portugal Adolfo Inza Julia Carpio Freddy Ccallo Igor Valdivia 《Journal of Seismology》2006,10(2):171-195
The western border of South America is one of the most important seismogenic regions in the world. In this region the most damaging earthquake ever recorded occurred. In June 23rd, 2001, another very strong earthquake (Mw = 8.1–8.2) occurred and produced death and damages in the whole southern region of Peru. This earthquake was originated by a friction process between Nazca and South American plates and affected an area of about 300 km × 120 km defined by the distribution of more than 220 aftershocks recorded by a local seismic network that operated 20 days. The epicenter of the main shock was localized in the northwestern extremity of the aftershock area, which suggests that the rupture propagated towards the SE direction. The modeling of P-wave for teleseismic distances permitted to define a focal mechanism of reverse type with NW-SE oriented nodal planes and a possible fault plane moving beneath almost horizontally in NE direction. The source time function (STF) suggests a complex process of rupture during 85 sec with 2 successive sources. The second one of greater size, and located approximately 100–120 km toward the SE direction was estimated to have a rupture velocity of about 2 km/sec on a 28°-dipping plane to the SE (N135°). A second event happened 45 sec after the first one with an epicenter 130km farther to the SE and a complex STF. This event and the second source of the main shock caused a Tsunami with waves from 7 to 8 meters that propagated almost orthogonally to the coast line, by affecting mainly the Camaná area.Three of all the aftershocks presented magnitudes greater or equal to Mw = 6.6, two of them occurred in front of the cities of Ilo and Mollendo (June 26th and July 7th) with focal mechanisms similar to the main seismic event. The aftershock of July 5th shows a normal mechanism at a depth of 75 km, and is therefore most likely located within the subducting Nazca plate and not in the coupling. The aftershocks of June 26th (Mw = 6.6) and July 5th (Mw = 6.6) show simple short duration STF. The aftershock of July 7th (Mw = 7.5) with 27-second duration suggests a complex process of energy release with the possible occurrence of a secondary shock with lower focal depth and focal mechanism of inverse type with a great lateral component. Simple and composed focal mechanisms were elaborated for the aftershocks and all have similar characteristics to the main earthquake.The earthquake of June 23rd caused major damages in the whole southern Peru. The damage in towns of Arequipa, Moquegua allow to consider maximum intensities from 6 to 7 (MSK79). In Alto de la Alianza and Ciudad Nueva zones from Tacna, the maximum intensity was of 7− (MSK79). 相似文献
45.
Adolfo Contreras Ruiz Esparza Pascal Douillet Jorge Zavala-Hidalgo 《Ocean Dynamics》2014,64(9):1349-1371
The tidal circulation patterns in the Terminos Lagoon were studied based on the analysis of 1 year of measurements and numerical simulations using a baroclinic 3D hydrodynamic model, the MARS3D. A gauging network was installed consisting of six self-recording pressure–temperature sensors, a tide gauge station and two current profilers, with pressure and temperature sensors moored in the main lagoon inlets. Model simulations were validated against current and sea level observations and were used to analyse the circulation patterns caused by the tidal forcing. The numerical model was forced with eight harmonic components, four diurnal (K 1, O 1, P 1, Q 1) and four semi-diurnal (M 2, S 2, N 2, K 2), extracted from the TPX0.7 database. The tidal patterns in the study area vary from mixed, mainly diurnal in the two main inlets of the lagoon, to diurnal in its interior. The tidal residual circulation inside the lagoon is dominated by a cyclonic gyre. The results indicate a net flux from the southwest Ciudad del Carmen inlet (CdC) towards the northeast Puerto Real inlet (PtR) along the southern side of the lagoon and the opposite in the northern side. The results indicate two areas of strong currents in the vicinity of the inlets and weak currents inside the lagoon. The area of strong currents in the vicinity of the CdC inlet is larger than that observed in the PtR inlet. Nevertheless, the current analysis indicates that the highest current speeds, which can reach a magnitude of 1.9 m s?1, occurred in PtR. A further analysis of the tide distortion in the inlets revealed that both passages are ebb dominated. 相似文献
46.
Héctor Pérez-de-Tejada Adolfo Orozco Murray Dryer 《Astrophysics and Space Science》1980,68(1):233-243
The interaction between the solar wind and cometary ionospheres downstream from the subsolar region is modeled in terms of viscous MHD flow theory. Calculations of the flow stremalines within the mixing region indicate that, as a result of viscous action, both the solar wind particles and the cometary material should be gradually directed towards the interior of the plasma wake to reinforce the formation of a type 1 tail. This behavior supports the notion that a transverse force acting on cometary plasma particles is actually responsible for the collapse of tail ray structures as suggested by Öpik (1964), Wurm (1968, 1975) and Wurm and Mammano (1972). 相似文献
47.
Adolfo G. Requejo James G. Quinn Juanita N. Gearing Patrick J. Gearing 《Organic Geochemistry》1984,7(1):1-10
Concentration profiles of five C25 and C30 biogenic alkenes in a sediment core collected from the upper anoxic basin of the Pettaquamscutt River have been determined. The five alkenes were identified usin gas chromatography/mass spectrometry as three isomeric C25 dienes, a C25 triene and a bicyclic C30 diene. All five compounds exhibit subsurface concentration maxima, thought to result from either preservation of a past increase in alkene production or a current bacterial in situ production at depth. Similarities exist in the concentrations of two alkenes common to this core and a core from upper Narragansett Bay, despite significant differences in the origin and content of sedimentary organic matter (as inferred from organic carbon and δ 13C measurements) at each location. These observations support the proposed bacterial in situ synthesis of alkenes. Other alkenes, whose concentration in sediments had been previously correlated with the incidence of marine organic matter, were not detected in the upper basin sediments. Their absence is consistent with the range of organic carbon δ 13C values measured, which indicate that the component originating from marine sources is small. A comparison of organic carbon and δ 13C values in this core with those previously reported from a core collected in an adjoining basin indicate that the sedimentary regimes at the two sites differ despite their close proximity and similar hydrography. 相似文献
48.
On 19th November 2002, the oil tanker Prestige (containing 77,000 tonnes of heavy fuel no. 2 (M100)) sank in 3500 m of water, off the coast of northwestern Spain. Intermittent discharge of oil from the stricken tanker, combined with large-scale sea surface dispersion, created a tracking and recovery problem. Initially, conventional oil recovery approaches were adopted, close to the wreck. With time and distance from the source, the oil dispersed dramatically and became less viscous. Consequently, a unique monitoring, prediction and data dissemination system was established, based upon the principles of 'operational oceanography'; this utilised in situ tracked buoys and numerical (spill trajectory) modelling outputs, in combination with remote sensing (satellite sensors and visual observation). Overall, wind effects on the surface waters were found to be the most important mechanism controlling the smaller oil slick movements. The recovery operation involved up to 180 fishing boats, 9-30 m in length. Such labour-intensive recovery of the oil (21,000 tonnes, representing an unprecedented ratio of 6.6 tonnes at sea, per tonne recovered on land) continued over a 10 month period. The overall recovery at sea, by the fishing vessels, represented 63% of the total oil recovered at sea; this compares to only 37% recovered by specialised 'counter- pollution' vessels. 相似文献