Dodi Sudiana

Analysis of Land Deformation on Slope Area using PS InSAR. Case Study: Malang Area

The geographical position of Indonesia located between two continents and oceans is strategic, but at large risk of experiencing various disasters. Climate change and vulnerable location (surrounded by plates and geological faults in the Earths crust) creates an earthquake-prone region and causes land/mudslides. In this paper, PS InSAR method (Persistent Scatterer Interferometric Synthetic Aperture Radar) is implemented to Phased Array type L-band Synthetic Aperture Radar (PALSAR) data to study the potential damage caused by the earthquake or volcanic eruption in Malang vicinity. By comparing the amplitude images periodically, shifting soil can be determined using precise orbital information. The analysis showed a significant decrease of land deformation on slope area in Klojen district in Malang city, reached up to –7.128 mm/year.The geographical position of Indonesia located between two continents and oceans is strategic, but at large risk of experiencing various disasters. Climate change and vulnerable location (surrounded by plates and geological faults in the Earths crust) creates an earthquake-prone region and causes land/mudslides. In this paper, PS InSAR method (Persistent Scatterer Interferometric Synthetic Aperture Radar) is implemented to Phased Array type L-band Synthetic Aperture Radar (PALSAR) data to study the potential damage caused by the earthquake or volcanic eruption in Malang vicinity. By comparing the amplitude images periodically, shifting soil can be determined using precise orbital information. The analysis showed a significant decrease of land deformation on slope area in Klojen district in Malang city, reached up to −7.128 mm/year.

Small format optical sensors for measuring vegetation indices in remote sensing applications: A comparative approach

In this paper we report the comparative study of two types of digital cameras to be used for vegetation index measurement. Using either a dedicated multispectral JAI AD-80-GE camera or a custom dual Canon S3IS camera system, we obtained RGB and NIR images and processed them to obtain vegetation indices (NDVI, EVI and two-band EVI). Since no radiometric calibration is available for both systems, normalized reflectance images are not available and we have to determine relative gain factors for the various bands in order to get likely vegetation indices. Moreover, the two camera system requires image registration. Experimental results are provided.

The Algebraic Reconstruction Technique of Lambert-Beer's attenuation approximation for parallel rays transmission projection

The Algebraic Reconstruction Technique (ART) of Lambert-Beers attenuation approximation for parallel rays transmission projection is a variant of the ART model that aims to solve image reconstruction problems in nuclear based computed tomography for non-destructive testing where γ or ϰ radiation is used as a ray source. In this model, the path length of the ray that hits a pixel at any projection view and the size of detector grid are explicitly included in computation. Then, the model is used to investigate the influence of the ray path length and the width of detector grid in producing image quality. The image quality is represented as space and pixel resolution, respectively. In this paper, we demonstrate that the model is able to show the contribution of the ray path length and detector grid in producing image quality. By considering ray path length and detector grid, the model produces smaller Root Mean Square error compared to conventional ART.

Geographic Information System (GIS)-based landslide susceptible area detection using geospatial and satellite data

This study focused on detection technique of landslide susceptible areas in Banten, DKI Jakarta and Jawa Barat by utilizing Weighted Linear Combination (WLC) method based on Geographic Information System using geospatial and satellite data. Several weighting approaches were used to examine the dominant landslide-controlling factors, e.g.: elevation, slope, soil type, land cover, rainfall average and standard deviation. WLC results showed that slope gradient was the most dominant factor which caused landslide events. This study also assessed the yearly distribution of landslide susceptible areas which not only depend on fluctuation of dynamic factors such as land cover and rainfall. The accuracy of the results depend on the precision and scale of geospatial data which could be increased using the latest satellite data.

Flood Potential Mapping of Pesanggrahan River Watershed in South and West Jakarta with LIDAR Data Segmentation

Degradation of environment quality is currently the prime cause of the recent occurrence 14 of natural disasters; it also contributes in the increase of the area that is prone to natural disasters. 15 This research is aimed to map the potential of areas around Pesanggrahan river in DKI Jakarta by 16 segmenting the Digital Elevation Model derived from LIDAR data. The objective of this 17 segmentation is to find the watershed lines of the DEM image. Data processing in this research is 18 using LIDAR data which take the ground surface data, which is overlaid with Jakarta river map 19 and subsequently, the data is then segmented the image. The expected result of the research is the 20 flood potential area information, especially along the Pesanggrahan river in South Jakarta. 21

Projection Matrix Design for Co-Sparse Analysis Model Based Compressive Sensing

Pekanbaru city has a landfill site (TPA). The local government estimated that it could only accommodate disposal for the next 2 years and a half. The aims of this research are: to identify a location suitable to be designated as a landfill site and considering to the land use change. The methods it employed were the overlay technique in Geographic Information System and Technique for Order Preference by Similarity to Ideal Solution (TOPSIS) as non-spatial analysis. Research findings found 4 feasible locations using GIS, i.e: Palas Sub-district and Rumbai Bukit Sub-district in Rumbai; Tebing Okura Sub-district in Rumbai Pesisir; Sail Sub-district in Tenayan Raya; and Labuh Baru Sub-district in Payung Sekaki District. From the TOPSIS, a number of locations with a specific rank were found such as: Rumbai, Rumbai Pesisir, Tenayan Raya & Tampan District. This research have one recommendation namely that Rumbai is the most suitable district to be designated as a landfill site.

Land Surface Deformation Mapping Method using PS-InSAR on ALOS/PALSAR Data in Bandung Region

The Earths land surface is always changing or deforming from time to time. This phenomenon occurs by natural, human factors or combination of both. Land deformation leads to destructive disaster and caused a great loss. A method for measuring and mapping land surface deformation, especially in urban area, is urgently needed. Earths surface deformation mapping using radar imagery from Synthetic Aperture Radar (SAR) remote sensing satellites have been actively developed since its image acquisition capabilities that can be performed in almost any conditions. SAR sensor signals can pass through clouds to overcome the difficulties in analyzing cloud-covered areas, such as in tropical area. In this research, we proposed land surface deformation mapping using PS-InSAR method on ALOS/PALSAR imageries. We analyzed the deformation rate from 10 ALOS/PALSAR scenes dated from June 10, 2007 to December 13, 2008. Results of the analysis showed that during the period, land surface deformation rate in almost all urban areas in Bandung, West Java, Indonesia is increasing. The highest land subsidence rate occurred in Cimahi and Bojong districts and recorded at 13.5 cm per year, respectively. Land subsidence in urban areas Bandung is caused by excessive use of ground water, new settlements, and changed land cover, especially in the industrial and settlement area.

A study of the partial acquisition technique to reduce the amount of SAR data

Synthetic Aperture Radar (SAR) technology is capable to provide high resolution image data of earth surfaces from a moving vehicle. This causes large volumes of raw data. Many researchs were proposed about compressed radar imaging, which can reduce the sampling rate of the analog digital converter (ADC) on the receiver and eliminate the need of match filter on the radar receiver. Besides the advantages, there is a major problem that produces a large measurement matrix, which causes a very intensive matrix calculation. In this paper is studied a new approach to partial acquisition technique to reduce the amount of raw data using compressed sampling in both the azimuth and range and to reduce the computational load. The results showed that the reconstruction of SAR image using partial acquisition model has good resolution comparable to the conventional method (Range Doppler Algorithm). On a target of a ship, that represents a low level sparsity, a good reconstruction image could be achieved from a fewer number measurement. The method can speed up the computation time by a factor of 2.64 to 4.49 times faster than with a full acquisition matrix.

Electrical Capacitance Volume Tomography static imaging using Compressive Sensing with l 1 sparse recovery

Compressive Sensing (CS) framework is mathematical framework to recover the signal by having less measurement data compared to Shannon-Nyquist theorem. It indicates the underdetermined linear system where the dimension of measurement data is much lower compared to dimension of the projected data. The basic idea of CS is to shift the sensing load into image reconstruction load. Thus, even though the sensing process produces less measurement data subject to the recovery data dimension, the CS theoretically is able to perform good signal recovery. Theoretically, CS should be working for natural sparse signal or sparse in transform domain. Electrical Capacitance Volume Tomography (ECVT) imaging forms naturally underdetermined linear system since the dimension of capacitance as the measurement data is much lower compared to dimension of predicted permittivity distribution. In addition, the ECVT signal is naturally sparse. Thus, the compressive sensing framework is theoretically promising for ECVT imaging. This paper will introduce ECVT static imaging based on compressive sensing framework. The early simulations show that compressive sensing with l1 optimization on the sparse recovery succeed to eliminate the elongation error on ECVT imaging by ILBP (Iterative Learning Back Propagation).

Analysis of excitation frequency to performance of electrical capacitance tomography

Electrical capacitance tomography (ECT) is one of imaging technique based on permittivity distribution of object inside the sensor. The principle of ECT is injection of square or sine wave signal with a certain frequency. In this paper, excitation frequencies of ECT system are analyzed in term of accuracy and systems performance. The frequency excitation will be scanned from 10 to 1500 kHz with 10 kHz of increment, hence the impedance value of ECT system can be obtained. Experiments using cylinder rods were conducted to validate the result of image reconstruction against excitation frequency. The good performance is in the frequency of 170–1000 kHz, which is the area at smaller impedance.