Time filter

Source Type

Tsuda T.,Kyoto University | Lin X.,Kyoto University | Lin X.,KDDI | Hayashi H.,Kyoto University | Noersomadi,National Institute of Aeronautics and Space LAPAN
Atmospheric Measurement Techniques | Year: 2011

GPS radio occultation (RO) is characterized by high accuracy and excellent height resolution, which has great advantages in analyzing atmospheric structures including small-scale vertical fluctuations. The vertical resolution of the geometrical optics (GO) method in the stratosphere is about 1.5 km due to Fresnel radius limitations, but full spectrum inversion (FSI) can provide superior resolutions. We applied FSI to COSMIC GPS-RO profiles from ground level up to 30 km altitude, although basic retrieval at UCAR/CDAAC sets the sewing height from GO to FSI below the tropopause. We validated FSI temperature profiles with routine high-resolution radiosonde data in Malaysia and North America collected within 400 km and about 30 min of the GPS RO events. The average discrepancy at 10-30 km altitude was less than 0.5 K, and the bias was equivalent with the GO results. Using the FSI results, we analyzed the vertical wave number spectrum of normalized temperature fluctuations in the stratosphere at 20-30 km altitude, which exhibits good consistency with the model spectra of saturated gravity waves. We investigated the white noise floor that tends to appear at high wave numbers, and the substantial vertical resolution of the FSI method was estimated as about 100-200 m in the lower stratosphere. We also examined a criterion for the upper limit of the FSI profiles, beyond which bending angle perturbations due to system noises, etc., could exceed atmospheric excess phase fluctuations. We found that the FSI profiles can be used up to about 28 km in studies of temperature fluctuations with vertical wave lengths as short as 0.5 km. © 2011 Author(s).


Strunz G.,German Aerospace Center | Post J.,German Aerospace Center | Zosseder K.,German Aerospace Center | Wegscheider S.,German Aerospace Center | And 15 more authors.
Natural Hazards and Earth System Science | Year: 2011

In the framework of the German Indonesian Tsunami Early Warning System (GITEWS) the assessment of tsunami risk is an essential part of the overall activities. The scientific and technical approach for the tsunami risk assessment has been developed and the results are implemented in the national Indonesian Tsunami Warning Centre and are provided to the national and regional disaster management and spatial planning institutions in Indonesia. The paper explains the underlying concepts and applied methods and shows some of the results achieved in the GITEWS project (Rudloff et al., 2009). The tsunami risk assessment has been performed at an overview scale at sub-national level covering the coastal areas of southern Sumatra, Java and Bali and also on a detailed scale in three pilot areas. The results are provided as thematic maps and GIS information layers for the national and regional planning institutions. From the analyses key parameters of tsunami risk are derived, which are integrated and stored in the decision support system of the national Indonesian Early Warning Centre. Moreover, technical descriptions and guidelines were elaborated to explain the developed approach, to allow future updates of the results and the further development of the methodologies, and to enable the local authorities to conduct tsunami risk assessment by using their own resources. © 2011 Author(s).


Budhiman S.,University of Twente | Budhiman S.,National Institute of Aeronautics and Space LAPAN | Suhyb Salama M.,University of Twente | Suhyb Salama M.,Netherlands Institute of Ecology | And 2 more authors.
ISPRS Journal of Photogrammetry and Remote Sensing | Year: 2012

The development of an operational water quality monitoring method based on remote sensing data requires information on the apparent and inherent optical properties of water (AOP and IOP respectively). This study was performed to determine the apparent and inherent optical properties of coastal waters of the Mahakam Delta, Kalimantan, Indonesia. Inherent optical properties (IOPs) were derived from above-water radiometric measurements and ocean color model inversion. Retrieved IOPs and measured concentrations show good agreement both for total suspended matter (TSM) and chlorophyll a (Chl a) (R 2=0.72 and 0.80 respectively). The linear relationship between the retrieved IOPs and the measured concentrations was then used to estimate the specific inherent optical properties (SIOPs) using the basic equation of the Lambert-Beer law. The specific backscattering coefficient of TSM (bb,TSM*(550)) was found to be 0.0087m 2g -1, and the specific absorption coefficient of Chl a (aChl*(440)) was found to be 0.023m 2g -1 in the Mahakam Delta. The estimated values of SIOP for TSM and Chl a could be considered spatially constant for the Mahakam Delta, and resulted in reliable estimates of TSM and Chl a concentrations (R 2=0.84 and 0.85 respectively). The specific backscattering coefficient of TSM found in this study is similar to that of the Barito Estuary (in the southern part of Kalimantan) but lower than that of the Berau Estuary (in the northern part of Kalimantan), whereas the specific backscattering coefficient of Chl a is similar to that found in the Berau Estuary. This study contributes to the development of an operational method based on remote sensing data to map water constituent concentrations in the Mahakam Delta, as well as to enrich the information about the optical properties of Indonesian waters. © 2012 International Society for Photogrammetry and Remote Sensing, Inc. (ISPRS).


Roza W.,National Institute of Aeronautics and Space LAPAN | El Amin D.,National Institute of Aeronautics and Space LAPAN | Nasser E.N.,Institute of Space Technology
Proceeding - ICARES 2014: 2014 IEEE International Conference on Aerospace Electronics and Remote Sensing Technology | Year: 2014

In order to transmit large amount of various payload data with the limited capacity channel, satellite requires payload data handling system. This paper presents the design and implementation of payload data handling for microsatellite based on FPGA Altera Cyclone IV EP4CE115F29C7. The proposed payload data handling design was divided into two main modules, CCSDS packet module and Reed-Solomon encoder module. Both modules were based on Packet Telemetry CCSDS recommendation. We proposed to use Reed-Solomon (223,255,16) interleave 5 for the outer code. Then followed by pseudo-random sequence and attached sync marker. The functional and performance test result shows and verify the functionality of Payload data handling FPGA implementation. The time required for generating 1 Frame was 54.68 ms for 25 Mbps. In order to synchronize the frame delay transition it requires 89 bytes dummy data. The proposed design uses 1627 total logic element and 92160 bit memory. © 2014 IEEE.


Arifin B.,National Institute of Aeronautics and Space LAPAN | Ross E.,Gemini Innovations | Brodsky Y.,European Space Agency
Proceedings of the International Astronautical Congress, IAC | Year: 2012

We are currently in the initial design phases of developing a ship detection and identification system (SDIS) which will integrate several data sources that can be used to detect and identify ships in real time and in any geographic region. The integration performed by the SDIS will exploit space-based data from optical and radar satellite imagery, AIS, VMS, and LRIT and terrestrial-based data from coastal and ship radar networks, coastal AIS networks, vessel registries and underwater acoustic and electromagnetic sensor networks. The system will be useful for many applications including security, monitoring of oil spills and other marine pollution and marine resource management. This presentation will highlight the system's extensibility and, in particular, the significance of this feature to developing countries. Many developing countries suffer from illegal exploitation of their exclusive economic marine resources and from marine security threats such as piracy. The SDIS can mitigate these issues by detecting and identifying ships in a region and estimating their behavior providing enforcement agencies with a prioritized list of potential of interest. Many resources are needed to establish and operate an integrated SDIS and these resources may not be available to some regions. Firstly, a certain level of technical expertise is necessary to set up the SDIS, integrate the system with sensor networks and other data streams, and operate it. Regions without these capabilities will have trouble implementing the SDIS while other regions would prefer to locally implement the system due to security and privacy concerns. Our business model offers two modes to address this. A region can subscribe to a service which provides ship detection and identification alerts as they occur. Alternatively, a region can purchase the system in order to implement and operate it locally. Secondly, a region may not have the infrastructure to provide all the possible data streams that can be used for ship detection and identification. The SDIS attempts to integrate as much data that is available and calculates a confidence level in each ship detection and identification event. This confidence level would increase with more available and frequent data. As a region expands its infrastructure, the SDIS can readily integrate new data streams. Additionally, it architecture allows for easy implementation of upgraded and expanded data processing algorithm. Copyright © (2012) by the International Astronautical Federation.


Tabata Y.,Kyoto University | Hashiguchi H.,Kyoto University | Yamamoto M.K.,Kyoto University | Yamamoto M.,Kyoto University | And 4 more authors.
Journal of Atmospheric and Solar-Terrestrial Physics | Year: 2011

Variations in the diurnal precipitation cycle over equatorial Indonesia was investigated using 1.3-GHz wind profiling radars (WPRs) and rain gauges installed at Pontianak (109.37°E, 0.00°S), Manado (124.92°E, 1.55°N), and Biak (136.10°E, 1.18°S). The horizontal scale of the landmass around Pontianak is more than 100. km, while those of Manado and Biak are 10-100. km. At all three WPR sites, peak rain rate was detected during 1300-1500 local time (LT) by rain gauges. WPR observations showed that deep convective clouds were predominant during that period. There was a clear difference in the afternoon-to-evening precipitation among the three WPR sites. At Pontianak, the afternoon-to-evening precipitation has the characteristics of a mesoscale convective system (MCS). Stratiform precipitation after the peak deep convective rain rate was predominant, and the transition from convective precipitation to stratiform precipitation was clearly apparent during 1500-2000LT. Black body brightness temperature (Tbb) observed by MTSAT-1R satellite also indicated that the precipitation clouds had enough horizontal scale to be well organized as an MCS. At Manado and Biak, the peak rain rate in the early afternoon was characterized by a short period (1-2h), and the precipitation after the convective precipitation was not clear. Tbb data showed that the convective precipitation had a horizontal scale of 10-100km. The difference of precipitation features among the three WPR sites is considered to be caused by the difference of horizontal scales of the respective landmasses. The diurnal precipitation cycle was also investigated using 11 years of Tropical Rainfall Measuring Mission (TRMM) data. A 3G68 product with a horizontal resolution of 0.5° could not resolve peak rain rate in the early afternoon at Manado and Biak, where convective clouds developed with the 10-100. km horizontal scale. Surface rain data with a horizontal resolution of 0.1° were produced using the TRMM precipitation radar (PR) 2A25 product. This high-horizontal-resolution data set successfully detected the peak convective rain rate in the early afternoon at Manado and Biak. © 2010 Elsevier Ltd.


Tabata Y.,Kyoto University | Hashiguchi H.,Kyoto University | Yamamoto M.K.,Kyoto University | Yamamoto M.,Kyoto University | And 4 more authors.
Journal of Atmospheric and Solar-Terrestrial Physics | Year: 2011

Horizontal wind data over Indonesia obtained by global reanalyses were compared with wind-profiling radar (WPR) observations in Indonesia at Kototabang (100.32°E, 0.20°S), Pontianak (109.37°E, 0.00°S), Manado (124.92°E, 1.55°N), and Biak (136.10°E, 1.18°S). The global-reanalysis data were 850- and 700-hPa horizontal winds for 2007 and 2008. These data were obtained from the National Centers for Environmental Prediction/National Center for Atmospheric Research (NCEP/NCAR) Reanalysis (R1), the NCEP-Department of Energy (DOE) Atmospheric Model Intercomparison Project (AMIP-II) Reanalysis (R2), the Japan Meteorological Agency Climate Data Assimilation System (JCDAS), the European Centre for Medium-Range Weather Forecasts (ECMWF) reanalysis-interim (ERA-Interim). All the four reanalyses showed good agreement with the WPR zonal and meridional wind data (correlation coefficient >0.7 in most cases). Of the four reanalyses, ERA-Interim had the highest correlation coefficient with the WPR winds in both zonal (correlation coefficient 0.89) and meridional (0.77) components. It can be explained that ERA-Interim used four-dimensional variational analysis (4D-var) for data assimilation, whereas the other reanalyses used three-dimensional variational analysis (3D-var). The zonal winds of the four reanalyses had smaller (78-87%) amplitudes than did the WPR winds. Further comparison of the zonal winds between the global reanalyses and operational radiosondes indicated that global-reanalysis zonal winds with smaller amplitudes are common in and around Indonesia. © 2010.


Noviar H.,National Institute of Aeronautics and Space LAPAN
34th Asian Conference on Remote Sensing 2013, ACRS 2013 | Year: 2013

Damage to mangrove forests in Bengkalis lately getting worse. This is due to the high forest exploitation of mangrove wood as a raw material for industry panglung. Mangrove forests need to be inventoried in this region because of its presence is essential for the survival and sustainability of biological resources and non-biological. The Remote sensing data can be used to detect the land cover in the earth surface. Based on this, researcher tried to inventory the mangrove forest in terms of location, extent and density using remote sensing data Landsat with consideration of spatial and spectral resolution for identification and monitoring of natural resources. The method is used are Landsat data interpretation visually and digitally using combination of the existing canal. These results are expected can be used as information and input for related parties such as the Ministry of Environment, local authorities and Riau Government in determining policies to preserve this area. The inventory result obtained the total area of Mangrove forests in District Bengkalis (before expansion) in 2010 was 44.173,8 hectares, while the most extensive mangrove forest is Sub-District Rupat (17.347,1 hectares or 39.3% of total area in Mangrove forest in Bengkalis). Canopy density of Mangrove forest which very sparse and sparse (indications of Mangrove forest damage) in Subdistrict Rupat totaling 404.6 Ha (2.3%) of the Mangrove total area in this sub-district. Copyright © (2013) by the Asian Association on Remote Sensing.


Budhiman S.,National Institute of Aeronautics and Space LAPAN | Ambarwulan W.,Geospatial Information Agency BIG | Widiatmaka,Bogor Agricultural University
34th Asian Conference on Remote Sensing 2013, ACRS 2013 | Year: 2013

Colored Dissolved Organic Matter (CDOM) is a product of plant and animal decomposition processes. Information of CDOM distribution is needed to determine water quality condition. The paper describes CDOM distribution in the Berau Delta coastal waters derived from in situ measurements and Medium Resolution Imaging Spectrometer (MERIS). Field measurements of CDOM absorption was carried out in January 2009. Three MERIS data: August 28, September 15 and September 30, 2007 were used in this study. Case-2 regional algorithm in BEAM VISAT software was used to process the MERIS data. The result indicated that the CDOM absorption in the Berau Delta coastal waters ranged from 1.67 m-1 in the river to 0.091 m-1 in clear open seawater.


Noviar H.,National Institute of Aeronautics and Space LAPAN
34th Asian Conference on Remote Sensing 2013, ACRS 2013 | Year: 2013

There are various data and algorithms that used to detect hotspot include NOAA-AVHRR data using LAPAN algorithms, MODIS data using NASA algorithms and ATSR data using ESA algorithms. The study result are comparison of hotspot detection algorithm and the hotspot detection results from the three sources of data (NOAA-AVHRR, MODIS WEBFIRE and ATSR) with 3 algorithms (LAPAN, NASA and ESA). Hotspot data dated October 3, 2006 obtained number of hotspot is same in South Sumatra Province from NOAA (NOAA-18) and ATSR data, i.e 140 points. Ogan Komering Hilir district as well and it's amount 80 point. Spatially, hotspot location from 3 data source (NOAA-18, ATSR and MODIS WEBFIRE) obtained same location, i.e cluster in the north eastern part of Ogan Komering district. Similarly in other districts in South Sumatra Province as Muaraenim, Musi Banyuasin and Musi Rawas district are also obtained same number of hotspot from 2 data sources (NOAA-18 and ATSR) on that date. The searching from another hotspot data obtained data dated October 1, 2006 in Kalimantan, especially in Central Kalimantan Province obtained number of hotspot almost the same from 2 data source (NOAA 1103 points, MODIS WEBFIRE 1156 points). From this study, it can be concluded that there are difference and similarities of number of hotspot daily from 3 data sources among other caused by differences in record time, clouds covering hotspots during recording and threshold values used. Copyright © (2013) by the Asian Association on Remote Sensing.

Loading National Institute of Aeronautics and Space LAPAN collaborators
Loading National Institute of Aeronautics and Space LAPAN collaborators