46 research outputs found
Recommended from our members
Optimum Object Analysis Of Islands Activities On South China Sea By DNB On VIIRS
A data processing and analyzing system was designed and made operational with free software to process the big data over the South China Sea (SCS), which are provided by the Visible Infrared Imaging Radiometer Suite (VIIRS) on the Suomi National Polar-orbiting Partnership (Suomi-NPP) to monitor the light distributions in the night. The VIIRS data are processed from the raw data (level-0) to geophysical data (level-3) using the International Polar Orbiter Processing Package (IPOPP), which are freely available from NASA. The Day Night Band (DNB) of VIIRS is extracted from the level-3 data and is geospatially projected for our region of interest (ROI) on the SCS. For those ingested data, an optimum object analysis in geographic domain was proposed to estimate the reclamation activities on coral reefs in the SCS using GDAL. A pixel base analysis of DNB data is possible to estimate the island activities independently among dredgers, support vessels, or buildings on coral reefs, but not appropriate to analyze the activities for as an integrated system or for the changes in the ROI. Although there is a difficulty to determine the scale of objects on the analysis of DNB data for the reclamation activities, the optimum object scale was empirically determined for different size of coral reefs and was applied for this study. The optimum object analysis determines the reclamation activities with including lights not only from buildings but also dredgers and supporting vessels around coral reefs
コウカイコウザ ホウコク ナツヤスミ タイケン コウザ デンシ マップ ヅクリ ニ チョウセン シヨウ イノウ タダタカ ノ ヨウニ
東京情報大学において、公開講座の一つとして、対象年齢層を広めに設定した『夏休み体験講座「電子マップ作りに挑戦しよう~伊能忠敬のように~」』を開講した。Google Earthと地理情報システム「ArcMAP」を利用した地図作りを体験して頂いた。幅広い年齢層とともに、地図作りに興味を持たれる方々であり、慣れないコンピュータ操作に対しても、果敢に挑戦され、地理情報システムを利用した地図作りであった
A Comparison of Global Estimates of Marine Primary Production From Ocean Color
The third primary production algorithm round robin (PPARR3) compares output from 24 models that estimate depth-integrated primary production from satellite measurements of ocean color, as well as seven general circulation models (GCMs) coupled with ecosystem or biogeochemical models. Here we compare the global primary production fields corresponding to eight months of 1998 and 1999 as estimated from common input fields of photosynthetically-available radiation (PAR), sea-surface temperature (SST), mixed-layer depth, and chlorophyll concentration. We also quantify the sensitivity of the ocean-color-based models to perturbations in their input variables. The pair-wise correlation between ocean-color models was used to cluster them into groups or related output, which reflect the regions and environmental conditions under which they respond differently. The groups do not follow model complexity with regards to wavelength or depth dependence, though they are related to the manner in which temperature is used to parameterize photosynthesis. Global average PP varies by a factor of two between models. The models diverged the most for the Southern Ocean, SST under 10 degrees C, and chlorophyll concentration exceeding 1 mg Chl m-3. Based on the conditions under which the model results diverge most, we conclude that current ocean-color-based models are challenged by high-nutrient low-chlorophyll conditions, and extreme temperatures or chlorophyll concentrations. The GCM-based models predict comparable primary production to those based on ocean color: they estimate higher values in the Southern Ocean, at low SST, and in the equatorial band, while they estimate lower values in eutrophic regions (probably because the area of high chlorophyll concentrations is smaller in the GCMs). Further progress in primary production modeling requires improved understanding of the effect of temperature on photosynthesis and better parameterization of the maximum photosynthetic rate
チイキ カダイ カイケツ ノ タメ ノ チリ ジョウホウ カツヨウ ノ ケンキュウ:カトリシ ダイイチ ヤマクラ ショウガッコウ ク ノ ジレイ オ チュウシン ニ シテ
現在、地域は様々な課題を抱えている。その解決のために必要な情報の一つとして地理情報がある。本論文は香取市第一山倉小学校区における防災目的の井戸地図作成の事例を考察している。考察においては、地理情報の基礎技術と応用技術に分けて検討している。基礎技術については地域の地図情報を普及し共有することの重要性について言及している。また応用技術については目的を明確にした地図情報の活用可能性について考察している。基礎技術と応用技術の面からの考察を通して、(1)地域における地図情報については安価なものが必要であること、(2)地域における地図情報を扱える人材を育成しておく必要があること、(3)地域における地図情報の普及のために多様なメディア(電子媒体および印刷媒体など)が必要であることが分かった。Recently we have some problems in local areas. For solving them, we need the geographicinformation. In this paper, we research map of well of Dai-ichi Yamakura elementary school areain KATORI City. We consider basic and practical technology of geographic information. In basictechnology part, we consider the importance of the common basic area map. In practical technologypart, we consider the possibility of area map for specific purpose.Considering basic and practical technology of area map, we find three points;( 1) we needgeographic information for areas on proper price,( 2) we need the talented person for treatinggeographic information,( 3) we need various media( electrical and printing) for diffusion ofgeographic information
リモートセンシング ト GIS ニ ヨル トチ リヨウ トチ ヒフク ノ ヘンカ ノ スイテイ ニ ツイテ :ガボン コク デ ラ モンダ ホゴ リン ノ バアイ
Foret Classee de la Mondah(FCM)ラ・モンダ保護林の土地利用・土地被覆(LULC)の変化について、定性的及び定量的に説明し、主な変動因子を求めた。このため、2000年4月7日にETM+、及び、2014年4月6日にOLIによる2時期の観測データについて、最尤法により分類後にLULCの変化を求めた。この結果、周辺地域の人口増加にともない宅地面積が20倍に急増し、不可逆的な人為的変化が見いだされた。これに加え、森林地域の面積が9.77%減少した。現地調査におけるGPSにより特定した位置情報、Google Earthによる高解像度データをサンプル領域の抽出あるいは分類結果の検証に利用した。LULCの持続的な管理を可能とするための保全政策を検討する段階で、政策立案者に対して、参照データとなる関連情報を見出すことができた。The Land Use / Land Cover (LUCL) changes in Foret Classee de la Mondah (FCM) in Gabon was studied to account for changes occurred in the past as a categorical and numerical changes and to explain their main driving causes. For this purpose, the LULC changes were analyzed using post-classification comparison technique, following to the maximum likelihood supervised classification, between two multi-temporal Landsat images of ETM+ and OLI, which were acquired on April 7th 2000 and April 6th 2014, respectively. Results highlighted irreversible human-induced changes, where the rapid growth of built-up areas exhibited 20 times from its initial area, because of the anthropogenic pressure of surrounding population. In addition, major changes occurred mainly in forested area with the loss of 9.77% of its initial area. During the classification process, the use of collateral data, such as GPS coordinates and high resolution images retrieved from ground survey and Google Earth, were extremely relevant to enhancement of sample selection of ROSs and for the validation of classification map as well. However, this study provided relevant findings which could be used as a reference for decision makers while developing conservation policies in order to generate sustainable LULC management practices
Assessing the uncertainties of model estimates of primary productivity in the tropical Pacific Ocean
Author Posting. © Elsevier B.V., 2009. This is the author's version of the work. It is posted here by permission of Elsevier B.V. for personal use, not for redistribution. The definitive version was published in Journal of Marine Systems 76 (2009): 113-133, doi:10.1016/j.jmarsys.2008.05.010.Depth-integrated primary productivity (PP) estimates obtained from satellite
ocean color based models (SatPPMs) and those generated from biogeochemical ocean
general circulation models (BOGCMs) represent a key resource for biogeochemical and
ecological studies at global as well as regional scales. Calibration and validation of these
PP models are not straightforward, however, and comparative studies show large
differences between model estimates. The goal of this paper is to compare PP estimates
obtained from 30 different models (21 SatPPMs and 9 BOGCMs) to a tropical Pacific PP
database consisting of ~1000 14C measurements spanning more than a decade (1983-
1996). Primary findings include: skill varied significantly between models, but
performance was not a function of model complexity or type (i.e. SatPPM vs. BOGCM);
nearly all models underestimated the observed variance of PP, specifically yielding too
few low PP (< 0.2 gC m-2d-2) values; more than half of the total root-mean-squared
model-data differences associated with the satellite-based PP models might be accounted
for by uncertainties in the input variables and/or the PP data; and the tropical Pacific
database captures a broad scale shift from low biomass-normalized productivity in the
1980s to higher biomass-normalized productivity in the 1990s, which was not
successfully captured by any of the models. This latter result suggests that interdecadal
and global changes will be a significant challenge for both SatPPMs and BOGCMs.
Finally, average root-mean-squared differences between in situ PP data on the equator at
140°W and PP estimates from the satellite-based productivity models were 58% lower
than analogous values computed in a previous PP model comparison six years ago. The
success of these types of comparison exercises is illustrated by the continual modification
and improvement of the participating models and the resulting increase in model skill.This research was supported by a grant from the National Aeronautics and Space Agency
Ocean Biology and Biogeochemistry program (NNG06GA03G), as well as by numerous
other grants to the various participating investigator
High-Frequency Nonlinear Internal Waves Around The Philippines
A study of satellite imagery over the Philippines undertaken as part of the US Office of Naval Research Philippine Straits Experiment (PhilEx) found significant high-frequency nonlinear internal wave activity in the waters around the Philippine Archipelago. Along with previously known nonlinear internal wave occurrence in the Sulu Sea and the Sulu Archipelago, the study found new areas of activity near Surigao Strait, within Butuan and Macajalar Bays along the northern coast of Mindanao in the southeastern Bohol Sea, in the Samar Sea, and at the shelf break at the northern end of the Sulu Sea between Palawan and Panay islands. Signatures in the imagery show that the surface expression of internal waves around the Philippines span a considerable spatial scale, from large solitary waves in the Sulu Sea (10-km scale) to very fine (10-m scale) wave packets found in Butuan Bay. This paper presents examples and discusses the characteristics of the nonlinear internal wave signatures observed in synthetic aperture radar and optical sunglint satellite imagery from around the Philippines
Extraction of Soil Information from Vegetated Area
Mix or influence of vegetation signal on soil information decrease the performance of soil identification and mapping. This paper describes a simple transformation to eliminate the mix or influence of vegetation reflectance on soil reflectance, and to enhance the soil information.
The usefulness of the transformation were investigated and shown by the channel selection based upon the statistical distance between soil classes and by multispectral pattern recognition. The simple transformation was considered to sensitive to the degree of the soil organic matter contents
<公開講座報告>夏休み体験講座「電子マップ作りに挑戦しよう~伊能忠敬のように~」
E(その他)東京情報大学において、公開講座の一つとして、対象年齢層を広めに設定した『夏休み体験講座「電子マップ作りに挑戦しよう~伊能忠敬のように~」』を開講した。Google Earthと地理情報システム「ArcMAP」を利用した地図作りを体験して頂いた。幅広い年齢層とともに、地図作りに興味を持たれる方々であり、慣れないコンピュータ操作に対しても、果敢に挑戦され、地理情報システムを利用した地図作りであった