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PENGGUNAAN TEKNOLOGI PENGINDERAAN JAUH DAN SISTEM INFORMASI GEOGRAFIS UNTUK MENGHITUNG PERSENTASE RUANG TERBUKA HIJAU DI DAERAH PERMUKIMAN KOTA DENPASAR I Wayan Nuarsa
Bumi Lestari Journal of Environment Vol 13 No 1 (2013)
Publisher : Environmental Research Center (PPLH) of Udayana University

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Abstract

AbstrakGreen open space (GOS) is a very important component in the arrangement of urban space,because the GOS has the function of ecological, aesthetic, social, cultural, and economic.Calculating of the GOS can easily be done in area that are enable for such purposes asurban forests, recreational areas of the city, as well as agricultural areas. However, for theland use consisting of non-GOS and GOS such as settlement, calculation of the GOS will bequite difficult. This research was conducted to measure the percentage of the GOS in settlementareas in the Denpasar city using remote sensing and geographic information systemtechnology. The results of this study showed that the percentage of the GOS in the settlementsarea of Denpasar ranged from 2.97% to 30.01%, with an average value of 14, 43%, and astandard deviation of 7.32% or 182.98 m2. The majority (50%) of the percentage of the GOSin the settlements area in the Denpasar city classified as moderate (10– 20%), 32% are low(<10%), and only 18% had a high percentage of the GOS (> 20%). Factors that influenceto the percentage of the GOS in the settlement area of Denpasar is the location of thesattements and the land area per housing unit.
PEMETAAN DAERAH RAWAN KEKERINGAN DI BALI-NUSA TENGGARA DAN HUBUNGANNYA DENGAN ENSO 2) MENGGUNAKAN APLIKASI DATA PENGINDERAAN JAUH I Wayan Nuarsa; I Wayan Sandi Adnyana; Abd. Rahman As-syakur
Bumi Lestari Journal of Environment Vol 15 No 1 (2015)
Publisher : Environmental Research Center (PPLH) of Udayana University

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Abstract

In this study, the use of SPI (Standardized Precipitation Index) combined with remote sensingdata is performed to map vulnerable drought areas in Bali-Nusa Tenggara regions. Analysisalso carried out to find the relationship between Vulnerable drought areas in Bali-NusaTenggara with El Niño phenomena. Bali-Nusa Tenggara islands are a chain of islands thathas a semi-arid climate type and resulted vulnerable to meteorological drought. Therefore,mapping of vulnerable drought areas in the region necessary to be carried out. The spatialpattern of the annual average value of SPI-6 in Bali Nusa Tenggara areas in 1998-2010indicates the spatial distribution follows the ENSO events. It also indicated in the spatialpattern relationship between ENSO and SPI in Bali-Nusa Tenggara islands. This studyindicates that remote sensing data such as TRMM 3B43 has the capability to be used as adata source to analyze the spatial patterns of vulnerable drought areas, particularly in theBali-Nusa Tenggara Islands. In addition, the TRMM data also possible to be used as a datasource to analyze the vulnerable drought areas in other parts of Indonesia.
AN APPLICATION OF SEGNET FOR DETECTING LANDSLIDE AREAS BY USING FULLY POLARIMETRIC SAR DATA I Made Oka Guna Antara; Norikazu Shimizu; Takahiro Osawa; I Wayan Nuarsa
ECOTROPHIC : Jurnal Ilmu Lingkungan (Journal of Environmental Science) Vol 13 No 2 (2019)
Publisher : Master Program of Environmental Science, Postgraduate Program of Udayana University

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (793.053 KB) | DOI: 10.24843/EJES.2019.v13.i02.p09

Abstract

The study location of landslide is in Hokkaido, Japan which occurred due to the Iburi Earthquake 2018. In this study the landslide has been estimated by the fully Polarimetric SAR (Pol-SAR) technique based on ALOS-2 PALSAR-2 data using the Yamaguchi’s decomposition. The Yamaguchi's decomposition is proposed by Yoshio Yamaguchi et.al. The data has been analyzed using the deep learning process with SegNet architecture with color composite. In this research, the performance of SegNet is fast and efficient in memory usage. However, the result is not good, based on the Intersection over Union (IoU) evaluation obtained the lowest value is 0.0515 and the highest value is 0.1483. That is because of difficulty to make training datasets and of a small number of datasets. The greater difference between accuracy and loss graph along with higher epochs represents overfitting. The overfitting can be caused by the limited amount of training data and failure of the network to generalize the feature set over the training images.
ESTIMASI PRODUKSI PADI DENGAN ANALISIS CITRA SATELIT LANDSAT 8 DI KABUPATEN KLUNGKUNG PROVINSI BALI Made Arya Bhaskara Putra; I Wayan Nuarsa; I Wayan Sandi Adnyana
ECOTROPHIC : Jurnal Ilmu Lingkungan (Journal of Environmental Science) Vol 12 No 1 (2018)
Publisher : Master Program of Environmental Science, Postgraduate Program of Udayana University

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (293.06 KB) | DOI: 10.24843/EJES.2018.v12.i01.p12

Abstract

Rice crop is one of the important commodities that must always be available, so estimation of rice production becomes very important to do before harvesting time to know the food availability. The technology that can be used is remote sensing technology using Landsat 8 Satellite. The aims of this study were (1) to obtain the model of estimation of rice production with Landsat 8 image analysis, and (2) to know the accuracy of the model that obtained by Landsat 8. The research area is located in three sub-districts in Klungkung regency. Analysis in this research was conducted by single band analysis and analysis of vegetation index of satellite image of Landsat 8. Estimation model of rice production was developed by finding the relationship between satellite image data and rice production data. The final stage is the accuracy test of the rice production estimation model, with t test and regression analysis. The results showed: (1) estimation of rice production can be calculated between 67 to 77 days after planting; (2) there was a positive correlation between NDVI (Normalized Difference Vegetation Index) vegetation index value with rice yield; (3) the model of rice production estimation is y = 2.0442e1.8787x (x is NDVI value of Landsat 8 and y is rice production); (4) The results of the model accuracy test showed that the obtained model is suitable to predict rice production with accuracy level is 89.29% and standard error of production estimation is + 0.443 ton/ha. Based on research results, it can be concluded that Landsat 8 Satellite image can be used to estimate rice production and the accuracy level is 89.29%. The results are expected to be a reference in estimating rice production in Klungkung Regency.
MODIFICATION OF INPUT IMAGES FOR IMPROVING THE ACCURACY OF RICE FIELD CLASSIFICATION USING MODIS DATA I Wayan Nuarsa; Fumihiko Nishio; Chiharu Hongo
International Journal of Remote Sensing and Earth Sciences (IJReSES) Vol 7, No 1 (2010): Vol 7,(2010)
Publisher : National Institute of Aeronautics and Space of Indonesia (LAPAN)

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (4197.946 KB) | DOI: 10.30536/j.ijreses.2010.v7.a1541

Abstract

The standard image classification method typically uses multispectral imageryon one acquisition date as an input for classification. Rice fields exhibit high variability inland cover states, which influences their reflectance. Using the existing standard method forrice field classification may increase errors of commission and omission, thereby reducingclassification accuracy. This study utilised temporal variance in a vegetation index as amodified input image for rice field classification. The results showed that classification ofrice fields using modified input images provided a better result. Using the modifiedclassification input improved the correspondence between rice field area obtained from theclassification result and reference data (R2 increased from 0.2557 to 0.9656 for regencylevelcomparisons and from 0.5045 to 0.8698 for district-level comparisons). Theclassification accuracy and the estimated Kappa value also increased when using themodified classification input compared to the standard method, from 66.33 to 83.73 andfrom 0.49 to 0.77, respectively. The commission error, omission error, and Kappa variancedecreased from 68.11 to 42.36, 28.48 to 27.97, and 0.00159 to 0.00039, respectively, whenusing modified input images compared to the standard method. The Kappa analysisconcluded that there are significant differences between the procedure developed in thisstudy and the standard method for rice field classification. Consequently, the modifiedclassification method developed here is significant improvement over the standardprocedure.
Pemetaan Perubahan Penggunaan Lahan Wilayah Pesisir di Kecamatan Bulak, Surabaya Tahun 2014 dan 2020 Maria Laurensyelen Wulu Beda Rianghepat; I Wayan Nuarsa; Ida Bagus Mandhara Brasika
Journal of Marine and Aquatic Sciences Vol 8 No 1 (2022)
Publisher : Fakultas Kelautan dan Perikanan Universitas Udayana

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.24843/jmas.2022.v08.i01.p15

Abstract

The coastal area is an intersection between mainland and ocean. The tourism potential in the coastal area of Bulak District in Surabaya is expanded. It is shown by the construction of Surabaya Bridge in 2015. This construction will affect land use change. Remote sensing technology is one of the acquisitions to monitor land use change. This research focuses on identifying the land use change in the coastal area in Bulak District, Surabaya, in 2014 and 2020, as well as to determine the accuracy of classification method applied for mapping the land use change in 2020. The application of 2014 acquisitions data was used as the bridge construction plan, while the application of 2020 acquisitions data was used as the premise for the land classification system in the previous year. There are two methods used to classify land use in coastal areas, that is pixel-based classification (maximum likelihood algorithm) and object-based classification (nearest neighbor algorithm). The research shows that there are 6 land use classes in study area: built-up land, rice fields, forests, shrubs, non-built-up land, and ocean. By applying these two methods, the result shows different area changes. The conversion of the highest mainland by applying a pixel-based classification was found in built-up land (+23.03 ha) and rice fields (-24.84 ha), while the area changes by applying object-based classification method were found in built-up land (+32.75 ha) and rice fields (-26.91 ha), respectively. The accuracy by applying the pixel and object-based method is 89% and 92%, respectively, from the percentage indicates good interpretation.
MODIFICATION OF INPUT IMAGES FOR IMPROVING THE ACCURACY OF RICE FIELD CLASSIFICATION USING MODIS DATA I Wayan Nuarsa; Fumihiko Nishio; Chiharu Hongo
International Journal of Remote Sensing and Earth Sciences Vol. 7 No. 1 (2010)
Publisher : BRIN

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.30536/j.ijreses.2010.v7.a1541

Abstract

The standard image classification method typically uses multispectral imageryon one acquisition date as an input for classification. Rice fields exhibit high variability inland cover states, which influences their reflectance. Using the existing standard method forrice field classification may increase errors of commission and omission, thereby reducingclassification accuracy. This study utilised temporal variance in a vegetation index as amodified input image for rice field classification. The results showed that classification ofrice fields using modified input images provided a better result. Using the modifiedclassification input improved the correspondence between rice field area obtained from theclassification result and reference data (R2 increased from 0.2557 to 0.9656 for regencylevelcomparisons and from 0.5045 to 0.8698 for district-level comparisons). Theclassification accuracy and the estimated Kappa value also increased when using themodified classification input compared to the standard method, from 66.33 to 83.73 andfrom 0.49 to 0.77, respectively. The commission error, omission error, and Kappa variancedecreased from 68.11 to 42.36, 28.48 to 27.97, and 0.00159 to 0.00039, respectively, whenusing modified input images compared to the standard method. The Kappa analysisconcluded that there are significant differences between the procedure developed in thisstudy and the standard method for rice field classification. Consequently, the modifiedclassification method developed here is significant improvement over the standardprocedure.
STUDY OF OCEAN PRIMARY PRODUCTIVITY USING OCEAN COLOR DATA AROUND JAPAN TAKAHIRO OSAWA; CHAOFANG ZHAO; I WAYAN NUARSA; SWARDIDAI I KETUT; YASUHIROSUGIMORI
International Journal of Remote Sensing and Earth Sciences Vol. 2 (2005)
Publisher : BRIN

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.30536/j.ijreses.2005.v2.a1354

Abstract

Ocean primary production is an important factor for determining the ocean's role in global carbon cycle. In recent years, much more chlorophyll-a concentration data in the euphotic layer were derived from the satellite ocean color sensors. The primary productivity algorithms have been proposed based on satellite chlorophyll measurements (Piatt, 1988; Morel, 1991) and other environmental parameters such as sea surfacetemperature or mixed layer depth (Behrenfeld and Falkowski, 1997; Esaias, 1996; Asanuma, 2002). In order to estimate integrated primary productivity in the whole water column, the vertical distribution of chlorophyll concentration below the sea surface should be reconstructed based on satellite data. In this paper, the vertical profile data of chlorophyll-a (Chl-a) measured around Japan Islands from 1974 to 1994 were reanalyzed based on the shifted-Gaussian shape proposed by Piatt et al (1988). Using this statistical model (neural network) and the photosynthesis irradiance parameters from Asanuma (2002), the distribution of primary productivity and its seasonal variation around Japan islands were estimated from SeaWiFS data, and the results were compared with in situ data and the other two models estimated from VGPM and mixed layer depth model.
A NEW APPROACH FOR THE TSUNAMI PREDICTION USING SATELLITE ALTIMETRY: TRIALS FOR ACEH TSUNAMI EVENTS IN 2004 AND 2005 Susumu Kanno; Yasuo Furushima; I Wayan Nuarsa; I Gede Hendrawan
International Journal of Remote Sensing and Earth Sciences Vol. 3 (2006)
Publisher : BRIN

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.30536/j.ijreses.2006.v3.a1204

Abstract

Change 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.
ESTIMATION OF TUNA FISHING GROUND IN LOW LATITUDE REGION USING SEA SURFACE HEIGHT GRADIENT DERIVED FROM SATELLITE ALTIMETRY: APPLICATION TO NORTHEASTERN INDIAN OCEAN Susumu Kanno; Yasuo Furushima; I Wayan Nuarsa; I Ketut Swardika; Atsushi Ono
International Journal of Remote Sensing and Earth Sciences Vol. 3 (2006)
Publisher : BRIN

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.30536/j.ijreses.2006.v3.a1209

Abstract

In order to improve the method for prediction of tuna fishing ground, the modification of the analysis about satellite altimeter data was made as trial. In this study, we focused on the satellite altimeter, TOPEX/POSEIDON series, to improve the method of fishing ground prediction. Fishery data were supplied as hook rate by local fishing information around Indonesia and hearing infromation. The gradient of sea surface height is calculated between the neighbor grid which has the maximum gradient. Result showed that the fishery data with hook rate over 0.8 are grouped in a zone from 1.0E-06 of sea prediction of fishing ground quantitatively, but also reasonable accuracy as shown in the change in the standard deviation. This method can be utilized for the effective fishing plan with the resource protection and the economy in the fishing operation in near future.