Joko Widodo

Chiba University · Center for Environmental Remote Sensing (CEReS)

Tropical peatland in Southeast Asia has undergone rapid degradation and shows large subsidence due to oxidation and peat shrinkage. The measurement of those deformations is thus valuable for evaluating the peat condition and assessing peat restoration. The time series interferometric synthetic aperture radar (TInSAR), especially with the small base...

In this research, we carried out the analysis of long-term continuous ground deformation (subsidence or uplift) based on C-band Differential Interferometric Synthetic Aperture Radar (DInSAR). This technique is employed to investigate ground deformation of the Yokohama and Miura cities of Kanagawa prefecture, Japan. The observation was starting from...

Several techniques have been proposed to observe long-term land surface deformation using phase information of synthetic aperture radar (SAR), for example, interferometric SAR (InSAR), differential interferometric SAR (DInSAR), permanent scatterer interferometric SAR (PS-InSAR), and small baseline subset (SBAS) using images of JERS-1, ALOS-1/2, ENV...

The significant ground deformation occurred at Lombok Island due to the large scale of series Earthquake in shallow depth from July to August 2018. Extract the information of ground deformation on the study area, Differential Interferometry Synthetic Aperture Radar (D-InSAR) technique was applied. The observation supported by SAR satellite data of...

A strong earthquake with M 6.4 in 14 km shallow depth occurs in the Eastern of Taiwan. To clarify the land deformation model and area damage covered, the SAR data of Sentinel-1A/B in ascending and descending orbit extracted. The data is collected from co-seismic and post-seismic. In processing SAR data, Differential Interferometry Synthetic Apertur...

Deforestation in peatland areas such as Kalimantan, Indonesia has been going on for decades. The deforestation has indirectly increased peatlands to become degraded and flammable. The Synthetic Aperture Radar (SAR) interferometry approach for identification of degraded peatlands can be performed using ALOS-2 PALSAR-2 data by converting land deforma...

Siak Regency is one of the areas in Indonesia that has peat areas. Events of forest fires occurring in Indonesia caused by the dryness of peatland attracted the attention of many parties to pay attention to this land as a serious matter. From this study, we found variations in soil moisture conditions around 11 - 50%, associated with soil content,...

Electromagnetic wave backscattering by corner reflectors in an anechoic chamber is studied using our developed computational tool. The tool applies the Finite-Difference Time-Domain (FDTD) method to simulate the propagation of the wave’s electric and magnetic fields. Experimental measurement in an anechoic chamber is also carried out as a compariso...

Mt Sinabung has been erupting and spewing fumes many times in the recent year after inactive for four centuries. This paper investigates the ground deformation due to the Mt Sinabung eruption in February 2018 using Differential Interferometry Synthetic Aperture Radar Technique (DInSAR). The deformation observed and extracted from Sentinel 1A satell...

In this paper, a soil moisture retrieval from full-polarimetric synthetic aperture radar (SAR) data is investigated for sparsely vegetated soil surfaces. An improved retrieval method adapting the variations in vegetation is proposed by incorporating the generalized volume model into the polarimetric two-scale two-component model (PTSTCM). The feasi...

Forest fire in Indonesia occurs mostly in peatland area. Dry peatland areas with ground water table more than 40 cm from the soil surface have become degradation areas with high potentials to fire. This paper presents a new novel to detect a peat fire risk area by incorporating two methods; the impedance model and the differential interferometric S...