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581.
Application of MK-PRISM for interpolation of wind speed and comparison with co-kriging in South Korea 总被引:1,自引:0,他引:1
Jongchul Park 《地理信息系统科学与遥感》2016,53(4):421-443
The spatial distribution of wind speed is important information required to understand climate-related regional phenomena. This paper presents the Modified Korean Parameter-elevation Regression on Independent Slopes Model (MK-PRISM) as a method for spatial interpolation of monthly wind speeds. A database of gridded monthly mean wind speeds with a spatial resolution of 1 km for the period of March 2011–February 2014 is constructed by MK-PRISM. Wind speed observation data collected from the 529 to 641 meteorological stations in South Korea were utilized as the input data for interpolation. The wind speed distribution estimated by co-kriging is used for comparison with the MK-PRISM results. Research demonstrates that the efficiency difference between the two models, MK-PRISM and co-kriging, is insignificant. The Kling and Gupta efficiencies of both models were 0.68-0.78 and the root mean square errors (RMSEs) were 0.44-0.68 m/s. The spatial distribution of wind speeds, however, differs between MK-PRISM and co-kriging, which can be considered a reflection of the influence of topographic features such as terrain convexity, aspect, and coastal proximity. MK-PRISM can perform more appropriately to represent the phenomena where similar wind speeds appear continuously along ridges and coastlines. This suggests that a knowledge-based approach that considers topographic features can be successfully applied to the interpolation of monthly or seasonal wind speeds, similar to temperature and precipitation. The wind speed distribution generated by MK-PRISM can be utilized as important data for different geographical studies. 相似文献
582.
Xiomara Cazañas Pura Alfonso Joan Carles Melgarejo Joaquín Antonio Proenza Anthony Edward Fallick 《Mineralium Deposita》2008,43(7):805-824
The El Cobre deposit is located in eastern Cuba within the volcanosedimentary sequence of the Sierra Maestra Paleogene arc.
The deposit is hosted by tholeiitic basalts, andesites and tuffs and comprises thick stratiform barite and anhydrite bodies,
three stratabound disseminated up to massive sulphide bodies produced by silicification and sulphidation of limestones or
sulphates, an anhydrite stockwork and a siliceous stockwork, grading downwards to quartz veins. Sulphides are mainly pyrite,
chalcopyrite and sphalerite; gold occurs in the stratabound ores. Fluid inclusions measured in sphalerite, quartz, anhydrite
and calcite show salinities between 2.3 and 5.7 wt% NaCl eq. and homogenisation temperatures between 177 and 300°C. Sulphides
from the stratabound mineralisation display δ
34S values of 0‰ to +6.0‰, whilst those from the feeder zone lie between −1.4‰ and +7.3‰. Sulphides show an intra-grain sulphur
isotope zonation of about 2‰; usually, δ
34S values increase towards the rims. Sulphate sulphur has δ
34S in the range of +17‰ to +21‰, except two samples with values of +5.9‰ and +7.7‰. Sulphur isotope data indicate that the
thermochemical reduction of sulphate from a hydrothermal fluid of seawater origin was the main source of sulphide sulphur
and that most of the sulphates precipitated by heating of seawater. The structure of the deposit, mineralogy, fluid inclusion
and isotope data suggest that the deposit formed from seawater-derived fluids with probably minor supply of magmatic fluids. 相似文献
583.
A fundamental procedure is proposed for the identification of liquefaction in saturated soils based on the instability in the material's microstructure. The disturbed state concept (DSC) provides a unified constitutive model for the characterization of entire stress–strain behaviour under cyclic loading, and the values of disturbance at threshold states in the deforming microstructure provides the basis for the identification of liquefaction. The procedure is verified with respect to laboratory behaviour of two sands, saturated Ottawa and Reid Bedford. A mathematical analysis of the DSC constitutive matrix is also performed. Procedures for the application of the DSC for simplified analysis and design, and in finite element procedures are presented. It is believed that the proposed model can provide a fundamental yet simplified procedure for liquefaction analysis, and as a result, it is considered to be an improvement over the available empirical and energy-based procedures. © 1998 John Wiley & Sons, Ltd. 相似文献
584.
A field study was conducted in 2003 to estimate the areal distribution and concentrations of polycyclic aromatic hydrocarbons (PAH) in intertidal sediments at sites of past human and industrial activity (HA sites) in Prince William Sound (PWS), Alaska, the site of the 1989 Exxon Valdez oil spill. More than 50 HA sites, primarily in western PWS, were identified through analysis of historic records and prior field studies, and nine sites were selected for detailed surveys. The areal assessment process consisted of seven steps: (1) identify site from historic records and field surveys; (2) locate visual evidence of surface oil/tar at a site; (3) prepare a site map and lay out a sampling grid over the entire site with 10-m grid spacing; (4) excavate pits to 50 cm depth on the grid; (5) perform a field colorimetric test to estimate total PAH (TPAH) in sediments from the wall of each pit and record the results in the ranges <1 ppm; 1-10 ppm; >10 ppm TPAH; (6) expand grid size if necessary if elevated PAH levels are detected colorimetrically; (7) select 20 samples from each site for same-day shipboard PAH analysis by immunoassay (SDI RaPID PAH) and, based on these results, select sediment samples from each site for full PAH analysis in the laboratory to identify PAH sources. A total of 416 pits were dug at the nine sites. Nine acres of sediments with TPAH >2500 ppb dry wt. were mapped at the nine sites. TPAH concentrations obtained by immunochemical analysis of 181 samples from the nine sites ranged from 20 to 1,320,000 ppb (wet wt.). The contaminants are mixtures of petroleum products (2-3 ring PAH) and combustion products (4-6 ring PAH) unrelated to the 1989 Exxon Valdez oil spill. Mussels and clams collected at these sites have elevated levels of PAH that are compositionally similar to the PAH in the sediments. These findings indicate that at least a portion of the sediment PAH is bioavailable. The PAH sources at these historic industrial sites are chronic. They include relict fuel oil tanks and works located above and within the intertidal zone, with contamination at some locations extending into nearshore sub-tidal sediments. This study shows how a hierarchical approach can be used to quickly and successfully map, quantify, and subsequently, identify sources of PAH in shoreline sediments. 相似文献
585.
James P. Cowen Miriam A. Bertram Edward T. Baker Richard A. Feely Gary J. Massoth Melanie Summit 《Deep Sea Research Part II: Topical Studies in Oceanography》1998,45(12):2713-2737
Event plumes form as episodic discharges of large volumes of hydrothermal solutions in response to magmatic diking/eruptive events. In consequence, event plumes represent the sudden injection of exploitable reduced chemical substrates, as well as inhibitory constituents, and likely induce successional changes in the microbial community structure and activity within event plume waters. In response to a major seismic event detected beginning 28 February 1996 at the northern Gorda Ridge, a series of three rapid response and follow-up cruises (GREAT 1, 2 and 3) were mounted over a period of three months. This report focuses on time-series measurements of manganese geomicrobial parameters in the two event plumes found in association with this seismic event.Scanning transmission electron microscopy, elemental microanalysis, and radioisotope (54Mn) uptake experiments were employed on samples collected from vertical and tow-yo casts from the three cruises. Numbers of bacteria and ratios of metal precipitating capsuled bacteria to total bacteria were greatest in the youngest (days old) plume, EP96A, found during GREAT 1; however, when normalized to the hydrothermal temperature anomaly, the greatest values were found in a second event plume, EP96B, discovered during GREAT 2 (up to 1 month old). Early capsule bacteria and particulate Mn distributions may have been influenced by entrainment of resuspended sediment, while those of the oldest (2–3 months) plume sample may have been subjected to preferential aggregation and particle settling. 相似文献
586.
Helmut Tenzer Chan-Hee Park Olaf Kolditz Christopher Ian McDermott 《Environmental Earth Sciences》2010,61(4):853-880
Earth-reservoirs are increasingly exploited today with the extraction of resources, such as heat and hydrocarbons, and the
large-scale emplacement of waste, such as CO2 sequestration. The characterization, site investigation, predictive modeling and long-term monitoring are dependent on the
processes being investigated and modeled. In most cases complex coupled processes have to be addressed in a geologically complex
rock mass system. In this paper we present a conceptual holistic framework known as geomechanical facies linking all the scales
of investigation, characterization and reservoir development methods. We demonstrate this concept on the work undertaken during
the design and development of the enhanced geothermal systems (EGS) systems at the forefront of European Hot-Dry-Rock (HDR)
technology, Soultz-sous-Forêts (France) and Spa Urach (Germany). Soultz-sous-Forêts is situated within granitic rocks and
an active tectonic graben system in the central part of the Rhine Graben. It presents conditions of lithology, temperature,
stress, hydraulics and geochemistry that are very different from those at Spa Urach, located in a very dense gneiss formation
in the South German crystalline complex. Spa Urach exhibits more elastic behavior and is set tectonically within an almost
inactive strike-slip stress field described in more detail in Sects. “Drill core analysis” and “Hydraulic stimulation at Spa Urach”. This paper compares the exploration and field development methods used at these two sites against the back drop of the
geomechanical facies concept. Issues addressed include the key parameters for flow and heat transport properties, coupled
hydro-mechanical process identification, the success of the HDR reservoir as a heat exchanger and exploration techniques applicable
to the different facies. Identification of the key geomechanical facies gives an indication as to which technologies will
prove more efficient in the application of HDR technology. The results of this study will hopefully help in developing heat
recovery schemes for the long-term economical operation of future HDR plants and EGS as well as assist in the understanding
of engineered geosystems. 相似文献
587.
Edward G. Gibson 《Icarus》1974,23(4):493-501
Visual observations of Comet Kohoutek (1973f) by the Skylab III astronauts are presented. They include the sighting of a sunward spike or “anti-tail” on the day after perihelion. 相似文献
588.
Edward G. Schmidt Jeffrey D. Rosendhal C. P. Jewsbury 《Astrophysics and Space Science》1974,29(2):397-414
Line strengths are presented for 15 yellow supergiants and 6 Cepheids. These line strengths are compared with those obtained
previously by other investigators.
Visiting Astronomer, Kitt Peak National Observatory, which is operated by the Association of Universities for Research in
Astronomy, Inc., under contract with the National Science Foundation. 相似文献
589.
Edward Scott 《Geochimica et cosmochimica acta》1978,42(9):1465
590.
Edward D. Goldberg Minoru Koide Kathe Bertine Vern Hodge Martha Stallard Darko Martincic Nevenka Mikac Marco Branica Jamal K. Abaychi 《Applied Geochemistry》1988,3(6)
Inorganic surfaces sorb dissolved and particulate phases from seawater onto organic films from a variety of sources. Heavy metals such as Au, Pt, Mn and Cd come to the coatings primarily from particulate phases. This observation confirms a previous finding of this laboratory for the uptake of U, Pu and Po. With depth in the open ocean there are greater contributions from the dissolved phases. Microbial and photochemical processes can enrich surfaces in some metals through reduction reactions. Copper and Mn enrichments in the films are attributed to the photo-reductions of Cu(II) to Cu(I) and manganese oxides to Mn(II), respectively, while the uptake of Mo is a consequence of the reduction, mediated by organisms, of molybdate to Mo(V) or Mo(IV). Cadmium, on the other hand, appears to be bioaccumulated in the films. 相似文献