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51.
Emerson Vieira Marcelino Antonio Roberto Formaggio Eduardo Eiji Maeda 《International Journal of Applied Earth Observation and Geoinformation》2009
The present work aims to assess the accuracy of six fusion techniques (Brovey, IHS, HSV, PCA, WTYO and WTVE) in order to compile landslide inventories using orbital images (ETM+ and PAN HRV). The study area is characterized by steep terrain and dense forest in Caraguatatuba, São Paulo State, Brazil. In terms of spatial quality, the Wavelet Transform technique provided the best results, presenting correlations above 90%. As for spectral quality, the best results were obtained with the IHS fusion. Based on the results, it may be concluded that the IHS is the best technique for preserving spatial and spectral information from the original images, so as to more clearly identify landslide scars. However, it was still not possible to typify the landslides from remote sensing data. Nonetheless, it is believed that image fusion techniques adequately met expectations in terms of their capacity to identify landslide for the creation of an inventory for the studied area. 相似文献
52.
Shingo Yamada Forecast Division Japan Meteorological Agency Tokyo Japan Shuhei Maeda Administration Division Climate Marine Department Japan Meteorological Agency Tokyo Japan K. Gambo c/o Department of Earth Planetary Physi 《大气科学进展》1997,(1)
NotesonExtended-RangeAtmosphericPredictionintheNorthernHemisphereWinterShingoYamadaForecastDivision,JapanMeteorologicalAgency... 相似文献
53.
As Japan’s leading contribution to the International Heliophysical Year (IHY), the Space Environment Research Center (SERC) of Kyushu University, Fukuoka, Japan is in the process of deploying globally 50 state-of-the-art magnetometers. In this brief article, we outline our progress to date (23 Sept 2007). We also briefly describe our magnetometer, which is able to send its data in near realtime to a central server, where data from all units can be compared with relative ease and quickness. 相似文献
54.
Ocean Science Journal - The genetic diversity and population structure of the fat greenling (Hexagrammos otakii) from the seven coastal locations in China, Korea, and Japan and the Okhotsk atka... 相似文献
55.
Eduardo E. Maeda Cláudia Maria de Almeida Arimatéa de Carvalho Ximenes Antonio R. Formaggio Yosio E. Shimabukuro Petri Pellikka 《International Journal of Applied Earth Observation and Geoinformation》2011
The present work is committed to simulate the expansion of agricultural and cattle raising activities within a watershed located in the fringes of the Xingu National Park, Brazilian Amazon. A spatially explicit dynamic model of land cover and land use change was used to provide both past and future scenarios of forest conversion into such rural activities, aiming to identify the role of driving forces of change in the study area. The employed modeling platform – Dinamica EGO – consists in a cellular automata environment that embodies neighborhood-based transition algorithms and spatial feedback approaches in a stochastic multi-step simulation framework. Biophysical variables and legal restrictions drove this simulation model, and statistical validation tests were then conducted for the generated past simulations (from 2000 to 2005), by means of multiple resolution fitting methods. Based on optimal calibration of past simulations, future scenarios were conceived, so as to figure out trends and spatial patterns of forest conversion in the study area for the year 2015. In all simulated scenarios, pasturelands remained nearly stable throughout the analyzed period, while a large expansion in croplands took place. The most optimistic scenario indicates that more than 50% of the natural forest will be replaced by either cropland or pastureland by 2015. This modeling experiment revealed the suitability of the adopted model to simulate processes of forest conversion. It also indicates its possible further applicability in generating simulations of deforestation for areas with expanding rural activities in the Amazon and in tropical forests worldwide. 相似文献
56.
The taphonomic features and paleoecology of this species were investigated focused on vertically embedded individuals of articulated Inoceramus amakusensis Nagao et Matsumoto. In the Hinoshima Formation, Himenoura Group of Kyushu, Japan, this Santonian (Late Cretaceous) inoceramid bivalve characteristically occurs in incised-valley fill siliciclastic marine deposits. Modes of I. amakusensis occurrence and preservation, from in situ (= occurrence in life position) to allochthonous shell fragments, are strongly affected by its paleoecology and depositional environments. Several I. amakusensis (up to 25 cm in shell height) were recovered from bioturbated sandstones associated with storm-influenced deposits. Their commissural planes are almost perpendicular to the bedding plane, with the anterior face oriented downward and the posteroventral portion extending upward. Furthermore, I. amakusensis is morphologically comparable to endobyssate mytilid bivalves today. These results suggest that this Cretaceous species was an orthothetic sand sticker at least during mid-ontogeny that preferentially inhabited a well-oxygenated, nearshore seafloor. I. amakusensis was distributed in various depositional environments and has been regarded as a recliner in offshore muddy substrate. However, the present discovery suggests that it was also well adapted, with an upright life position, to high-energy shallow clastic environments characterized by high sediment supply. 相似文献
57.
Ken’ichi Nomoto Keiichi Maeda Nozomu Tominaga Takuya Ohkubo Jinsong Deng Paolo A. Mazzali 《Astrophysics and Space Science》2005,298(1-2):81-86
The nature of very energetic supernovae (hypernovae) is discussed. They are the explosive death of stars more massive than
~20–25M
⊙, probably linked to the enigmatic Gamma-Ray Bursts. The optical properties of hypernovae indicate that they are significantly
aspherical. Synthetic light curves and late-phase spectra of aspherical supernova/hypernova models are presented. These models
can account for the optical observations of SNe 1998bw and 2002ap. The abundance patterns of hypernovae are characterized
by large ratios (Zn, Co)/Fe and small ratios (Mn, Cr)/Fe, indicating a significant contribution of hypernovae to the early
Galactic chemical evolution. 相似文献
58.
59.
Copepods are considered to be a vital component connecting the unique macrotidal environment to the high productivity and high biodiversity of the Ariake Sea. To examine the spatiotemporal succession of copepod communities, we conducted monthly sampling (vertical hauls of a 100-μm mesh plankton net) in three neighboring macrotidal estuaries between 2005 and 2006. Irrespective of the season, three copepod communities were recognized in relation to the relatively long gradients of salinity and turbidity along the Chikugo and Midori River estuaries. The oligohaline community (salinity 1–10) was observed at higher turbidities (>100 NTU), whereas the freshwater (salinity <1) and meso/polyhaline (salinity >10) communities were associated with lower turbidities (<100 NTU). The oligohaline calanoid Sinocalanus sinensis occurred only in the Chikugo River estuary, maintaining a large biomass (dry weight >10 mg m?3) in or close to the well-developed estuarine turbidity maximum (ETM) throughout the year. In the Midori River estuary, the oligohaline community lacked S. sinensis and showed a minimum biomass during winter (<10 mg m?3). In both estuaries, the freshwater community always remained at a small biomass (<1 mg m?3), whereas the meso/polyhaline community showed marked seasonal changes in biomass (0.1–657 mg m?3). The prevalence of higher salinities allowed only the meso/polyhaline community to occur in the Kuma River estuary. In summary, S. sinensis characterized the copepod community distinctive of the well-developed ETM, potentially serving as an important link to higher trophic levels during winter when copepods are scarce in other areas. 相似文献
60.
We investigated the development of a distinct later phase observed at stations near the Japan Trench associated with shallow, outer-rise earthquakes off the coast of Sanriku, northern Japan based on the analysis of three-component broadband seismograms and FDM simulations of seismic wave propagation using a heterogeneous structural model of the Japan Trench subduction zone. Snapshots of seismic wave propagation obtained through these simulations clearly demonstrate the complicated seismic wavefield constructed by a coupling of the ocean acoustic waves and the Rayleigh waves propagating within seawater and below the sea bottom by multiple reflections associated with shallow subduction zone earthquakes. We demonstrated that the conversion to the Rayleigh wave from the coupled ocean acoustic waves and the Rayleigh wave as they propagate upward along the slope of seafloor near the coast is the primary cause of the arrival of the distinct later phase at the station near the coast. Through a sequence of simulations using different structural models of the Japan Trench subduction zone, we determined that the thick layer of seawater along the trench and the suddenly rising sea bottom onshore of the Japanese island are the major causes of the distinct later phase. The results of the present study indicate that for realistic modeling of seismic wave propagation from the subduction zone earthquakes, a high-resolution bathymetry model is very crucial, although most current simulations do not include a water column in their simulation models. 相似文献