Ratih Dewanti Dimyati, Ratih
LAPAN and Gadjah Mada University

Published : 2 Documents
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STUDY OF SHORT MACKEREL CATH, SEA SURFACE TEMPERATURE, AND CHLOROPHYLL -A IN THE MAKASSAR STRAIT Semedi, Bambang; Dewanti Dimyati, Ratih
International Journal of Remote Sensing and Earth Sciences (IJReSES) Vol 6,(2009)
Publisher : National Institute of Aeronautics and Space of Indonesia (LAPAN)

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (1816.546 KB) | DOI: 10.30536/j.ijreses.2009.v6.a1241

Abstract

The Makassar Strait is the major fishing ground for Short Mackerel (Rastrelliger spp) fisheries in South Sulawesi, Indonesia using both commercial fishing vessels and boats with traditional fishing gear. Though Short Mackerel is one of dominant commercial food fishes in South Sulawesi, the annual Cath per Unit Effort (CPUE) has been decreasing from year to year. In 2000, the total of annual CPUE was 22,117 tons and in 2007, it was 17,596 tons. The purpose of this research was to forecast the fishing ground of Short Mackerel employing Moderate Resolution Imaging Spectroradiometer (MODIS) satellite images in Makassar Strait territory with the study interest of 3 S and to 5 S and 118 E to 120 E. This research was conductade from September 15 to October 20, 2007. Fishing data were collected from the fishermen including fishing locations, catch, sea surface temperature, and chlorophyll concentrations. To determine the relationship between cacth and oceanographic parameters, linear regression was employed. We also examined sea surface temperature (SST) and Chlorophyll-a concentration field data vs. MODIS satellite data. The result showed that SST andChlorophyll distributions have close relationship with the distribution of fishing location of Short Mackerel. The fishing location tends to spread on the waters with the SST ranged from 26 degree of celcius to 29 degree of celcius and Chlorophyll concentration from 1.19 mg per m to 1.25 mg per m. Keywords: Chlorophyll-a, MODIS, Sea Surface Temperature.
A Minimum Cloud Cover Mosaic Image Model of the Operational Land Imager Landsat-8 Multitemporal Data using Tile based Dewanti Dimyati, Ratih; Danoedoro, Projo; Hartono, Hartono; Kustiyo, Kustiyo
International Journal of Electrical and Computer Engineering (IJECE) Vol 8, No 1: February 2018
Publisher : Institute of Advanced Engineering and Science

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.11591/ijece.v8i1.pp360-371

Abstract

The need for remote sensing minimum cloud cover or cloud free mosaic images is now increasing in line with the increased of national development activities based on one map policy. However, the continuity and availability of cloud and haze free remote sensing data for the purpose of monitoring the natural resources are still low. This paper presents a model of medium resolution remote sensing data processing of Landsat-8 uses a new approach called mosaic tile based model (MTB), which is developed from the mosaic pixel based model (MPB) algorithm, to obtain an annual multitemporal mosaic image with minimum cloud cover mosaic imageries. The MTB model is an approach constructed from a set of pixels (called tiles) considering the image quality that is extracted from cloud and haze free areas, vegetation coverage, and open land coverage of multitemporal imageries. The data used in the model are from Landsat-8 Operational Land Imager (OLI) covering 10 scenes area, with 2.5 years recording period from June 2015 to June 2017; covered Riau, West Sumatra and North Sumatra Provinces. The MTB model is examined with tile size of 0.1 degrees (11x11 km2), 0.05 degrees (5.5x5.5 km2), and 0.02 degrees (2.2x2.2 km2). The result of the analysis shows that the smallest tile size 0.02 gives the best result in terms of minimum cloud cover and haze (or named clear area). The comparison of clear area values to cloud cover and haze for three years (2015, 2016 and 2017) for the three mosaic images of MTB are 68.2%, 78.8%, and 86.4%, respectively.