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Moukomla S.,Geo Informatics and Space Technology Development Agency GISTDA | Blanken P.D.,University of Colorado at Boulder
Remote Sensing | Year: 2017

This study provides the first technique to investigate the turbulent fluxes over the Great Lakes from July 2001 to December 2014 using a combination of data from satellite remote sensing, reanalysis data sets, and direct measurements. Turbulent fluxes including latent heat flux (QE) and sensible heat flux (QH) were estimated using the bulk aerodynamic approach, then compared with the direct eddy covariance measurements from the rooftop of three lighthouses-Stannard Rock Lighthouse (SR) in Lake Superior, White Shoal Lighthouse (WS) in Lake Michigan, and Spectacle Reef Lighthouse (SP) in Lake Huron. The relationship between modeled and measured QE and QH were in a good statistical agreement, for QE, R2 varied from 0.41 (WS), 0.74 (SR), and 0.87 (SP) with RMSE of 5.68, 6.93, and 4.67 W·m-2, respectively, while QH, R2 ranged from 0.002 (WS), 0.8030 (SP) and 0.94 (SR) with RMSE of 6.97, 4.39 and 4.90W·m-2 respectively. Both monthly mean QE and QH were highest in January for all lakes except Lake Ontario, which was highest in early December. The turbulent fluxes then sharply drop in March and are negligible during June and July. The evaporation processes continue again in August. © 2017 by the authors.

Moukomla S.,Geo Informatics and Space Technology Development Agency GISTDA | Blanken P.D.,University of Colorado at Boulder
Proceedings of SPIE - The International Society for Optical Engineering | Year: 2016

We computed Net Basin Supplies to the Great Lakes by estimated over-lake evaporation using the bulk aerodynamic method and derived over-lake precipitation from MERRA associated with the runoff data provided by GLERL. The long-Term trend of NBS components that are over-lake evaporation rate, over-lake precipitation and runoff were also addressed. We also evaluated the relationship between NBS and change in water level for each of the Great Lakes. The simple correlation analysis was performed in order to determine the relationship between the climate teleconnection indices with NBS, over-lake precipitation, and over-lake evaporation. A brief review on the effect of climate teleconnection on the Great Lakes NBS, over-lake evaporation, and over-lake precipitation were given in the last section. The distribution of over-lake precipitation is spread throughout the year with two peaks in April and October. The monthly average of runoff entering to the Great Lakes was highest in April while the lowest monthly mean runoff was in September. The evaporation rate was highest in January for all Lakes but Lake Ontario, which was highest in early December. The evaporation rate then sharply drops in March the evaporation processes continue again in August. The calculations of NBS were limited by the availability of runoff data. The highest NBS was in April while the lowest monthly average NBS was varied in December, January, and February. The correlation analysis was based on various teleconnection indices and NBS, over-lake evaporation, and over-lake precipitation. NAO was positively correlated with NBS in all Lakes but Lake Superior while over-lake evaporation showed a negative correlation with PDO and Niño 3.4. © 2016 SPIE.

Longepe N.,Collecte Localisation Satellites CLS | Rakwatin P.,Geo Informatics and Space Technology Development Agency GISTDA | Isoguchi O.,Japan Aerospace Exploration Agency | Shimada M.,Japan Aerospace Exploration Agency | And 2 more authors.
IEEE Transactions on Geoscience and Remote Sensing | Year: 2011

From its launch in 2006, the phased array L-band synthetic aperture radar (PALSAR) onboard the advanced land observing satellite (ALOS) has acquired many dual-polarized (FBD) images with a 70-km swath width, aiming to produce spatially consistent coverage over tropical rainforest. This paper investigates the relevancy of PALSAR orthorectified FBD product at 50-m resolution for regional land cover classification by the support vector machines (SVM). Our test site is the Riau province, Sumatra island, Indonesia, known to hold vast area of natural peatland forest with an extreme biodiversity threatened by industrial deforestation. Since it is demonstrated the radiometric information (HH and HV channels) cannot be solely used to achieve a good classification, the spatial information in these orthorectified data is investigated. A new tool using the recursive feature elimination SVM-based process and the textural Haralick's parameters is introduced. The real contribution of textures within the land cover classification can be understood. A small set of textural parameters is determined at local scale while being optimal for the land cover discrimination. The SVM-based classifier is carried out across the whole Riau province and its results are compared with a Landsat-based estimation. The agreement is over 70% with six classes and 86% for the natural forest map. These results are remarkable since only one PALSAR FBD product is used and this assessment is performed on more than 40 million pixels. The results confirm the high potential of the PALSAR sensor for forest monitoring at regional, if not global scale. © 2011 IEEE.

Malyavej V.,Mahanakorn University of Technology | Udomthanatheera P.,Geo Informatics and Space Technology Development Agency GISTDA
Proceedings of the 20th Asia-Pacific Conference on Communication, APCC 2014 | Year: 2015

The most crucial problem in navigation system is localization. The global positioning system (GPS) has long been used in mobile unit localization. However, GPS is incapable in some situation such as indoor environment. The received signal strength indicator (RSSI) from wireless communication is a promising alternative method to derive the location of a mobile unit. To improve the precision and robustness in the GPS-based localization, an inertial measurement unit (IMU) is normally used. In this paper, we study the possibility to use RSSI from wireless local area network (WLAN) and an IMU to derive the location of the mobile unit. We apply unscented Kalman filter (UKF) as a fusion engine for those two information. The experiment is conducted by using mobile unit equipped with low-cost IMU and a wireless communication module together with multiple access points to evaluate the performance of our algorithm, and the result is promising. © 2014 IEEE.

Moukomla S.,Geo Informatics and Space Technology Development Agency GISTDA | Blanken P.D.,University of Colorado at Boulder
Remote Sensing | Year: 2016

The Great Lakes Surface Temperature (GLST) is the key to understanding the effects of climate change on the Great Lakes (GL). This study provides the first techniques to retrieve pixel-based GLST under all sky conditions by merging skin temperature derived from the MODIS Land Surface Temperature (MOD11L2) and the MODIS Cloud product (MOD06L2) from 6 July 2001 to 31 December 2014, resulting in 18,807 scenes in total 9373 (9434) scenes for MOD11L2 (MOD06L2). The pixel-based GLST under all sky conditions was well-correlated with the in situ observations (R2 = 0.9102) with a cool bias of -1.10 °C and a root mean square error (RMSE) of 1.39 °C. The study also presents the long-term trends of GLST. Contrary to expectations, it decreased slightly due to the impact of an anomalously cold winter in 2013-2014. © 2016 by the authors.

Techavijit P.,Geo Informatics and Space Technology Development Agency GISTDA
62nd International Astronautical Congress 2011, IAC 2011 | Year: 2011

THEOS (THailand Earth Observation Satellite), Thailand's First Earth observation satellite on Low Earth Orbit (LEO), was launched on 1st October 2008 and is fully operated by GISTDA(Geo-Informatics and Space Technology Development Agency) at the control ground station located in Siracha, Chonburi Province. Satellite monitoring and controlling are the main responsibility of Mission Control Division (MCD). MCD engineers' roles are to perform Telemetry downlink in order to acquire Housekeeping Data and Telecommand uplink in order to send mission program and specific operational commands to the satellite via control ground software. These require precise operations within each visibility (lasts approximately 10 minutes). Therefore all MCD engineers need to be well trained and passed through numerous qualification processes. In order to assist the engineer and to reduce human error, specific templates of procedures were used while preparing commands and recording real time monitoring of satellite parameters. However there were still errors from data searching in limited time, error in log book recording due to the different standard of operators. Other constraints included data storage area and operational bring discrepancy. To address these issues, MCD engineers have developed an active tool to prepare a set of commands and record real time satellite parameters in electronic form. This software is also capable of estimating duration which guarantees secure operation of command uplink. All operational data are then archived in electronic database system that allows quick access. MCD engineers also implement new features for security by improving the existing satellite control software to run consistently with existing satellite control software in order to reduce risk of single event upset. These implement projects are designed for supporting THEOS-1 and upgrading with new feature for THEOS-2 in the future. Copyright © 2011 by the International Astronautical Federation. All rights reserved.

Sachasiri R.,Geo Informatics and Space Technology Development Agency GISTDA
62nd International Astronautical Congress 2011, IAC 2011 | Year: 2011

Satellite operators find downtime unacceptable due to the limited lifetime of the satellite. Every minute that the satellite is not doing its work means loss in revenue. Failure of ground station equipments result in loss that might have been avoided by good maintenance. However, there are times when failures are unpredictable and the operator may not all the spare parts available. The goal of ground station sharing between earth observation satellite operators is to help overcome this obstacle - with minimum cost. The paper shall discuss the cooperation to share ground station resources between Geo-Informatics and Space Development Agency (GISTDA), Thailand and National Space Organization (NSPO), Taiwan in order to build partnerships and reduce operating costs. Both the agencies have gained immensely from this joint venture. In fact, GISTDA has operated the Thailand Earth Observation Satellite (THEOS) for seventy-two days using only NSPO's ground station in Taiwan. The setup process, both bureaucratic and technical, may be difficult but the outcome is very rewarding. Furthermore, this cooperation can easily grow from two partners to a pool of members who are always contributing various ground station resources to the pool when they do not need it. Members of the pool are then free to use these available resources as per their convenient. Naturally, resource management is done to optimize the available resources. This way, every member can aim to accomplish one hundred percent daily satellite access during its lifetime. Any ground station failure can be compromise by using another ground station, at minimum operating cost. Copyright ©2010 by the International Astronautical Federation. All rights reserved.

Nilnarong T.,Geo informatics and Space Technology Development Agency GISTDA
International Conference on Space Science and Communication, IconSpace | Year: 2013

Solar activities cast impacts on the operations of satellites in several aspects of the orbit mechanics segment. These impacts include the precision of orbit determination, the number of necessary station keeping maneuvers, and the awareness of close-approaches with space objects. All of which affect the mission, the lifetime of satellite, as well as the risk of collision with space debris. The purpose of this study is to examine the extent of these impacts on the THAICHOTE satellite and present the practical solutions which are implemented in daily operations. The results of this study will be useful for the design the in-house orbit determination software currently under development. © 2013 IEEE.

Sachasiri R.,Geo Informatics and Space Technology Development Agency GISTDA
Proceedings of the International Astronautical Congress, IAC | Year: 2012

The Space Krenovation Park (SKP), Thailand's first science park concentrating on space technology development, is a brainchild project of the current management of the Geo-Informatics and Space Technology Development Agency (GISTDA). The SICP has been initiated to strengthen GISTDA's two-pronged strategy - To induce value creation and bring about social benefits. The SKP is being set up at the current Thaichote (THEOS) ground station in Siracha, Chonburi. Keeping in line with the organization's strategy, the SKP, in order to bring about value creation, will provide several services to accelerate economic and knowledge growth in Thailand. The SKP will host a business incubation center for entrepreneurial development as well as a technology-training center for personnel development. The Board of Investment of Thailand (BOI) has also promised to provide momentum to the project by providing financial incentives in term of special tax structures and soft loans for companies to set up in the SKP. With the possibility that new local companies setting up and more players entering the local space industry, sustainable development can be guaranteed. On the other hand, in order to bring about social benefits, GISTDA is leveraging the SKP to include a Space Technology Development Center and to be the Research and Development center for future ASEAN space activities. This will be set up side by side with the Visionarium, a Space Knowledge Center, which shall provide knowledge and infotainment to the general public through exhibits and outreach programs. Therefore, the four pillars of the SKP - Business Incubation Center, Space Technology Center, Space and Geo-Informatics System (GIS) Training Center and the Visionarium - Are the tools for the development of the space industry in Thailand. Copyright © (2012) by the International Astronautical Federation.

Wanwiwake T.,Geo Informatics and Space Technology Development Agency GISTDA
34th Asian Conference on Remote Sensing 2013, ACRS 2013 | Year: 2013

The Geo-Informatics and Space Technology Development Agency (GISTDA) responsible for all space technology activities and geo-informatics applications in Thailand. In order to provide a better access to Earth Observation Satellite (EOS) data, Thailand first Ground Receiving Station was established in 1982. In 2008, the first THailand Earth Observation Satellite (THEOS) (later renamed as THAICHOTE) was successfully launched into space. Since then, the Space technology became very valuable national asset. Therefore, to continue to grow with the GISTDA's vision, "Delivering Values from Space", the development and space technology and their related technology is encouraged by the Thai Government. GISTDA's second ground station was established in 2012, a Space Krenovation Park (SKP) has officially been opened at Sriracha, Chonburi province. Apart from business opportunity, SKP brings in many opportunity for researches and developments. Micro- and small satellite project is one of the vital areas. Research and development road maps have been planned with the focus on technology demonstration, research, know-how and skill development rather than the applications. There is a lot of room for cooperation, research and development opportunities.

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