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A NEW APPROACH FOR THE TSUNAMI PREDICTION USING SATELLITE ALTIMETRY: TRIALS FOR ACEH TSUNAMI EVENTS IN 2004 AND 2005
No full textChange in the sea surface height anomaly derived from satellite altimeter was examined and applied to evaluate the possibility of tsunami prediction before the occurance. Sea surface height anomaly was composed period during earthquake and tsunami occurance. Daily variability in the sea surface height anomaly was traced about the location of hypocenter, aftershock, and the end of erthquakes from satellite altimetry. Results shows that there are the locations where the sea surface height anomaly suddenly increased or decreased before tsunami event at least. This result can be utilized and applied for the development in not only the stunami monitoting system as the disaster monitoring, but also for the effective tsunami prediction system in the near future
DEVELOPMENT OF THE NEW ALGORITHM FOR MANGROVE CLASSIFICATION
No full textThe objective of the study is to develop the algorithm for mangrove classification and density. Regression and correlation analysis was used to perform the equation. CE1 = (0.663*Band 3) + (0.l55 *Band 4) - (l.4*Band 5) + 0.995 And CE2 = 36 * Band 4 + 6*Band 5 + Band 3 were two formula that have been used to classify the mangrove. The object will be classified as mangrove when the value of CE1 is between -31.439 and 0.888, and value of CE2 is greater than or equal to 2000. On the other hand, density of the mangrove was expressed as DE = (2 * Band 4)/(Band 1+Band 3). Mangrove classification result in this study was similar to those of the existing methods. Statistical approach in this study generally gives the higher result tendency than other methods
ESTIMATION OF FISHERY RESOURCES BY M-F GIS USING SATELLITE DATA AND ITS APPLICATION TO TAC FOR SUSTAINABLE FISHERY PRODUCTION
No full textRESEARCH ON TECHNOLOGY DEVELOPMENT FOR FISHING VESSELS IDENTIFICATION BY SATELLITE REMOTE SENSING - STATUS IN DEVELOPED COUNTRIES AND JAPANESE PATROL SYSTEM
No full textCurrent status and trends ov vessel detection, identification technology development and application in major countries were surveyed. According to increasing the number of foreign poaching and suspicious vessels intrusion into EEZ, patroliling by vessel and airplane does not satisfy the needs because of narrow coverege and observation frequncey. The satellite monitoring by SAR and optical sensor has been studied and partially used, but there are several disavantages such as observation frequncy, geometric occuracy and weather dependence to adopt for operational use. This paper describes an optimize system for vessel detection and identification by combining patrolling vessel, airplane and satellite
INTERNAL WAVES DYNAMICS IN THE LOMBOK STRAIT STUDIED BY A NUMERICAL MODEL
No full textA baroclinic 3D hydrodynamic model with the non-hydrostatic approximation called Massachusetts Institute of Technology Global Circulation Model (MIT gcm) has been applied to simulate the generation of internal tidal bores and their disintegration into internal solitary waves in the Strait of Lombok. Numerical simulation have been carried out by incorporating seasonal variations of the stratification of the water body, which exist during the first transitional monsoon, the east monsoon, the second transitional monsoon, and the west monsoon. Our simulation yields the results that the existence of the sill at the southern part of the Lombok Strait, strong tidal flow, and a stratified fluid, play an important role in forming some short of divergence and convergence area as an indication of the birth of internal waves, which are simulated on the both sides of the sill. The simulated results reproduce reasonably well the basic features of internal waves in the Strait of Lombok as captured by the Synthetic Aperture Radar (SAR) from the European Remote Sensing (ERS) satellites ERS 1 and ERS 2, such as a north-south asymmetry, propagation speeds, average amplitudes and wavelengths, and solution packets. Similiar to observations made by National Oceanic and Atmospheric Administration (NOAA) satellites, the simulation results also showed the intrusion of warmwater from thePacific Ocean into the Indian Ocean and the exitence of well-developmed thermal plume at south of the sill. Seasonal variations of interface depth of thermocline and the density difference between the stratified layers influence magnitudes of the amplitudes and wavelengths of the internal waves and solitons, and the distance of thermal plume in the Lombok Strait. It is found that during the monsoon transition periods and the west monson, the amplitudes of internal waves and solitons at the southern part of the strait is apparently larger than those at the northern one, whereas during the east monsoon, the wave amplitudes is large north of the sill than south of it. Meanwhile, the propagation speeds of northward propagating internal solitary waves (0.71-2.67m per s) are stronger than southward propagating ones (0.21-1.53 m per s) throughout the monsoon periods
RELATIONSHIPS BETWEEN RICE GROWTH PARAMETERS AND REMOTE SENSING DATA
No full textRice is an agriculture plants that has the specific characteristic in the life stage due to the growth stage having different proportion of vegetation, water, and soil. Vegetation index is one of the satellite remote sensing parameter that is widely used to monitor the global vegetation cover. The objective of the study is to know the spectral characteristic of rice plant in the life stage and find the relationship between the rice growth parameters and the remote sensing data by the Landsat ETM data using the correlation and regression analysis. The result of study shows that the spectral characteristic of the rice before one month of age is defferent comparing after one month. All of the examined vegetation index has close linear relationship with rice coverage. Difference Vegetation Index (DVI) is the best vegetation index which estimates rice coverage with equation y = 1.762x + 2.558 and R degree value was 0.946. Rice age has a high quadratic relationship with all of evaluated vegetation index. Transformed Vegetation Index (TVI) is the best vegetation to predict the age of the rice. Formula y = 0.013x - 1.625x + 145.8 is the relationship form between the rice age and the TVI with R = 0.939. Peak of the vegetation index of rice is in the rice age of 2 months. This period is the transition of vegetative and generative stages
Evaluation of Artificial Neural Networks Technique for Calibration of Five-Hole Probe Measurement
No full textIn the present study, the Artificial Neural Networks (ANN) technique was implemented to predict the flow parameters of a Five-Hole Probe (FHP). The experimental data were obtained from a subsonic open jet wind tunnel at a speed increased from 0 to 1180 rpm in increments of 200 rpm. The ANN approach is carried out in stages, starting with the method of selecting training data and validation, then increasing the number of neurons, varying the correlation between the activation function and the optimizer, and finally finding the optimal number of hidden layers. In the ANN approach, the mean absolute errors of 0.2705, 0.3326, and 1.0748 were achieved for estimating angle α which represents the angle of attack, angle β which represents the angle of sideslip, and speed, respectively. At the end of this study, the results were compared with the rational function approach. It was concluded that the ANN approach was more accurate compared to the rational function based on statistical parameters such as mean absolute error, max absolute error, and coefficient of determination (r2)
A Review of Absolute Radiometry Calibration Method for Satellite Multispectral Camera while in Orbit
No full textMultispectral cameras on satellites are a type of camera that is widely used in satellite remote sensing and has wide applications. Therefore, it is necessary to carry out absolute radiometric calibration to maintain the accuracy of radiometric information in satellite camera images. There are several types of absolute radiometric calibration, including onboard, Rayleigh, vicarious, and cross-calibration. These methods have strengths and weaknesses. Therefore, it is necessary to conduct a literature review to find out which calibration method is appropriate for certain conditions. Based on a literature review, all methods can be used and adapted to the conditions of the satellite. The onboard calibration method is suitable for satellites equipped with calibration instruments. The Rayleigh calibration method is suitable for large FOV cameras with visual wavelengths. The vicarious calibration method is suitable for satellites from countries close to standardized calibration sites. Meanwhile, the cross-calibration method is suitable for satellites cameras that have specifications and conditions close to the reference camera. Therefore, these calibration methods can be carried out together to complement each method
Numerical Investigation of Supersonic and Hypersonic Shock-Wave/Boundary-Layer Interactions
No full textNumerical simulations of 2-D supersonic and hypersonic laminar Shock-Wave/Boundary-Layer Interactions (SBLIs) were carried out by solving the Navier-Stokes (NS)equations using a compressible flow code over a wide range of Mach numbers and shockstrengths. The results obtained at Mach 2.0 and 7.73 were compared with experimentaldata. In addition, the numerical data were further analyzed using correlation laws derivedby previous researchers based on the free interaction concept, extended here to higherMach numbers. The results indicate that this concept is valid for separated laminar hypersonicflows with SBLIs. For interference heating, the correlation technique based on thewell-established power law relationship between peak heating and peak pressures yieldedencouraging results consistent with other correlations for laminar interference heating athypersonic speeds
EVALUASI KINETIKA DEKOMPOSISI TERMAL PROPELAN KOMPOSIT AP/HTPB DENGAN METODE KISSINGER, FLYNN WALL OZAWA DAN COATS - REDFREN
No full textMekanisme dan kinetika dekomposisi propelan telah diinvestigasi menggunakan DTG/TA dengan tiga jenis metode yang berbeda yaitu Kissinger, Flynn Wall Ozawa dan Coats & Redfern. Penelitian ini bertujuan untuk mengetahui parameter kinetika dekomposisi propelan LAPAN. Propelan yang digunakan memiliki perbedaan komposisi Al dan jenis moda AP. Propelan RUM adalah propelan AP/HTPB. RX 450 adalah AP/HTPB/ Al (bimoda). Sementara itu, RX 1220 adalah AP/HTPB/ Al (trimoda). Pengujian termal berlangsung pada suhu 30 - 400oC dan atmosfer nitrogen berlaju alir 50 ml/menit. Hasil penelitian mengungkapkan bahwa semua jenis propelan terdekomposisi dengan mekanisme F1 (nukleasi acak dengan satu nukleus pada partikel individu). Energi aktivasi propelan berkisar antara 100,876 – 155,156 kJ/mol sementara faktor pre-eksponensial berkisar antara 4,57 x 107 – 3,46 x 1012/min. Energi aktivasi (E) dan faktor pre-eksponensial (A) RX 1220 adalah terendah dari ketiga sampel. Penggunaan jenis AP trimodul menciptakan efek katalitik yang menurunkan besarnya energi aktivasi. Propelan RX 1220 lebih mudah terdekomposisi (lebih mudah bereaksi) daripada propelan RUM dan RX 450.Â