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211.
Interferometric synthetic aperture radar (InSAR) analysis is a radar technique for generating large-area maps of ground deformation using differences in the phase of microwaves returning to a satellite. In recent years, high-resolution SAR sensors have been developed that enable small-scale slope deformation to be detected, such as the partial block movement of a landslide. The L-band SAR (PALSAR-2) is mounted on Advanced Land Observing Satellite-2 (ALOS-2), which was launched on 24 Mar. 2014. Its main improvements compared with ALOS are enhanced resolution of as high as 3 m with a high-frequency recurrence period (14 days). Owing to its high resolution and the use of the L-band, PALSAR-2 can obtain reflective data passing through a tree canopy surface, unlike the other synthetic aperture radars. Therefore, the coherence of InSAR in mountainous forest areas is less likely to decrease, making it advantageous for the extraction of slope movement. In this study, to verify the accuracy of InSAR analysis using PALSAR-2 data, we compared the results of InSAR analysis and the measurement of the displacement in a landslide by global navigation satellite system (GNSS) observation. It was found that the average difference between the displacements obtained by InSAR analysis and the field measurements by GNSS was only 15.1 mm in the slant range direction, indicating the high accuracy of InSAR analysis. Many of the areas detected by InSAR analysis corresponded to the locations of surface changes due to landslide activity. Additionally, in the areas detected by InSAR analysis using multiple datasets, the ground changes due to landslide movement were confirmed by site investigation. 相似文献
212.
Culture-dependent and independent analyses of subsurface microbial communities in oil-bearing strata of the Sagara oil reservoir 总被引:3,自引:0,他引:3
Takuro Nunoura Hanako Oida Noriaki Masui Fumio Inagaki Ken Takai Satoshi Hirano Kenneth H. Nealson Koki Horikoshi 《Island Arc》2006,15(3):328-337
Abstract Culture-dependent and independent methods were used to evaluate the microbial communities in cores collected at depths up to 200 m in oil-bearing and oil-free strata near the Sagara oil reservoir near Shizuoka, Japan. Direct microbial counts revealed much higher numbers (2.2 × 104 −7.9 × 106 /g) of microbes in the oil-bearing strata than in the oil-free zones, where counts were uniform at approximately 1.0 × 104 /g. Molecular taxonomic analyses via 16S rRNA gene sequence comparisons showed that the oil-free strata were dominated by members of the γ-Proteobacteria including Pseudomonas , Stenotrophomonas and Sphingomonas , whereas the oil-bearing strata were dominated by a single species closely related to Pseudomonas stutzeri . All archaeal clones were phylogenetically affiliated with the uncultured soil group in Crenarchaeota with the exception of a single phylotype that belonged to the genus Thermococcus . Culture-dependent analysis was carried out by most-probable-number culturing as well as direct plating to determine viable cell counts, using both complex organic substrates or native oil and autotrophic media. Both culture-dependent and independent methods revealed the abundant cultivable member was the aerobic oil-degrading bacterium Pseudomonas stutzeri and neither autotrophs nor anaerobic heterotrophs could be detected in the oil-bearing strata. 相似文献
213.
214.
Concentration of polychlorinated biphenyls (PCBs) in beached resin pellets: variability among individual particles and regional differences 总被引:1,自引:0,他引:1
Endo S Takizawa R Okuda K Takada H Chiba K Kanehiro H Ogi H Yamashita R Date T 《Marine pollution bulletin》2005,50(10):1103-1114
Concentrations of polychlorinated biphenyls (PCBs) in beached resin pellets were examined to reveal variability between individual particles and differences among beaches. Fifty-five resin pellets from a beach in Tokyo were individually analyzed for PCBs, and showed concentrations ranging from <28 to 2,300 ng/g. This indicates that concentrations are highly variable between particles. Among several characters, discoloration (e.g., yellowing) had a positive relationship with PCB concentration: discolored pellets contained more PCBs than others on most of the beaches sampled. Given the color-selective ingestion of food by some organisms, this may be ecotoxicologically important. Measurements of samples from 47 beaches in Japan showed regional differences in PCB concentrations in resin pellets consistent with those in mussels. Sporadic high concentrations of PCBs were also found in pellets from remote islands, suggesting that resin pellets could be the dominant route of exposure to the contaminants at remote sites. The similarity of PCB concentrations between resin pellets and mussels suggests a potential use of resin pellets to monitor pollution in seawater. 相似文献
215.
A. Sugimoto D. Naito N. Yanagisawa K. Ichiyanagi N. Kurita J. Kubota T. Kotake T. Ohata T. C. Maximov A. N. Fedorov 《水文研究》2003,17(6):1073-1092
Soil moisture and its isotopic composition were observed at Spasskaya Pad experimental forest near Yakutsk, Russia, during summer in 1998, 1999, and 2000. The amount of soil water (plus ice) was estimated from volumetric soil water content obtained with time domain reflectometry. Soil moisture and its δ18O showed large interannual variation depending on the amount of summer rainfall. The soil water δ18O decreased with soil moisture during a dry summer (1998), indicating that ice meltwater from a deeper soil layer was transported upward. On the other hand, during a wet summer (1999), the δ18O of soil water increased due to percolation of summer rain with high δ18O values. Infiltration after spring snowmelt can be traced down to 15 cm by the increase in the amount of soil water and decrease in the δ18O because of the low δ18O of deposited snow. About half of the snow water equivalent (about 50 mm) recharged the surface soil. The pulse of the snow meltwater was, however, less important than the amount of summer rainfall for intra‐annual variation of soil moisture. Excess water at the time just before soil freezing, which is controlled by the amount of summer rainfall, was stored as ice during winter. This water storage stabilizes the rate of evapotranspiration. Soil water stored in the upper part of the active layer (surface to about 120 cm) can be a water source for transpiration in the following summer. On the other hand, once water was stored in the lower part of the active layer (deeper than about 120 cm), it would not be used by plants in the following summer, because the lower part of the active layer thaws in late summer after the plant growing season is over. Copyright © 2002 John Wiley & Sons, Ltd. 相似文献
216.
In order to estimate the distribution of pressure and transmissibility in the Otake Geothermal Reservoir, in which flow can be assumed to be two-dimensional and horizontal, well-head pressure and flow rates measured at both production and reinjection wells, and the time required for a tracer to arrive at certain production wells from one of the reinjection wells were analyzed. Analysis of these data was performed by means of an equation which was obtained by combining the Darcy and the continuity equations, in which the transmissibility and two components of the flow remain unknown. Estimation of pressure and transmissibility distributions and flow patterns within the reservoir was possible by numerical solution of this equation using the finite-difference method and by assuming suitable boundary conditions. 相似文献
217.
Akiko Sugimoto Yukio Nobe Takafumi Yamazaki Yutaka Anzai Kiyoshi Yamagishi Yusaburo Segawa Humihiko Takei 《Physics and Chemistry of Minerals》1997,24(5):326-332
Four kinds of Cr-droped melilite crystals, Ca2MgSi2O7 (akermanite), CaAl2SiO7 (gehlenite), CaGa2SiO7 (Ga-gehlenite) and CaGa2GeO7 (GaGe-gehlenite), with different sizes of the sites for Cr ions to substitute, were grown in series, using both the CZ and
FZ techniques. Although Cr4+ is regarded as a major species in melilites, the existence of Cr6+ in gehlenite is also suggested from the change in absorption spectra by annealing, and the dependence of distribution coefficient
of Cr ions on growth atmosphere. Spectral peak shifts are not obvious if the host crystal field is altered in melilites, because
the local environment of the sites for Cr ion is possibly changed by reforming the packing features of the host lattice.
Received February 7, 1996 / Revised, accepted September 20, 1996 相似文献
218.
219.
220.
L. G. Wang S. Yamashita F. Sugimoto C. Pan G. Tan 《Rock Mechanics and Rock Engineering》2003,36(2):121-142
Summary In block caving, it is important to estimate the cavability of an ore body. This study proposes a new three dimensional (3D)
model for predicting the characteristics of ore fragmentation in block caving, which is based on the Monte Carlo simulation
technique. In this paper, the following subjects are discussed: sampling methods of discontinuity, 3D modeling algorithms
and conceptualization for analyzing the distribution of discontinuities. In addition, the influence of each modeling parameter
on the distribution of ore fragmentation was analyzed. The characteristics of ore fragmentation in a Northern China underground
copper mine are used as a case study. Based on the methods discussed here, a software system named “MAKEBLOCK” was developed
for analyzing the characteristics of discontinuities in an ore body and predicting the size distribution of ore fragments
in block caving. The ore fragmentation attained by using this 3D model is in a good agreement with the field fragmentation
measurements.
Received November 30, 2001; accepted September 19, 2002; Published online February 25, 2003
Acknowledgement Support for this project came primarily from The National Science Foundation of China (approval No. 59704004). We would like
to thank professor J. F. Archbald, head of Faculty of Mining Engineering, Queen's University, Canada, for his excellent advice
and for checking the technical presentations of this paper.
Authors' address: Dr. Liguan Wang, College of Resources and Safety Engineering, Central South University, Hunan, Changsha, China; e-mail: liguan_wang@hotmail.com 相似文献