Coastline Modeling Accuracy Assessment Developed By Using from Multi-Source Data. The coastal reg... more Coastline Modeling Accuracy Assessment Developed By Using from Multi-Source Data. The coastal regions need to be developed because many big cities in Indonesia are located in these areas. However, it is crucial to determine the distance from the beach that is safe as the requirement for development along the coastal zone. The term of the beach is very closely affiliated with the coastline. The method of determining the coastline continues to be developed to fulfill the many needs related to the coastline. The coastline has a dynamic position. The land contour along the coast and the tide's state become several things that affect the coastline. Therefore, a dynamic model is required to define coastline positioning because both conditions are easy to change. The coastline determination from multi-source data modeling using DEM results is rarely done. In this study, coastline determination uses land height contours combined with sea depth contours and uses Mean Sea Level (MSL) valu...
IOP Conference Series: Earth and Environmental Science, 2021
To use the Global Navigation Satellite System (GNSS) correctly, the height information should be ... more To use the Global Navigation Satellite System (GNSS) correctly, the height information should be transformed into orthometric height by subtracting geoid undulation from it. This orthometric height is commonly used for practical purposes. In 2015 geoid of Jakarta has been produced, and it has an accuracy of 0.076 m. In the year 2019, airborne gravimetry has been done for the entire Java Island. The area of DKI Province cannot be measured because there is inhibition from Airnav. For this reason, terrestrial gravimetric measurements are carried out in this region by adding points outside the previously measured area. To compute the geoid in the Jakarta region is needed the Global Geopotential Model (GGM). In this paper, the GMM used is gif48. The “remove and restore” method will be used in calculating the geoid in this Jakarta region. Besides that in this geoid calculation also uses Stokes kernel and FFT to speed up the calculation. The verification of the resulting geoid is carried w...
IOP Conference Series: Earth and Environmental Science, Jun 1, 2018
Nowadays satellite altimetry has become an advanced instrument to observe many natural physical p... more Nowadays satellite altimetry has become an advanced instrument to observe many natural physical phenomena, such as sea-level rise, ocean circulation, water mass changes, and marine gravity anomaly. The use of satellite altimetry data to compute marine gravity anomaly provides good results and costs relatively low. Those advantages make geodesists utilize this method as an alternative in geoid determination, especially over the seas. Several sets of satellite altimetry data from Cryosat 2, Jason 1 phase C, Geosat and ERS1 were used to compute gravity anomaly over the surrounding waters of Kalimantan and Sulawesi Island in Indonesia. The study area spans between -7°-7° N and 108°-127° E with a spatial resolution of 1'x1'. In the pre-processing step, the altimetry data especially Geosat and ERS1, were retracked to reduce errors due to the land influence. The main computation step was done by using two different methods, least square collocation (LSC) and Inverse Vening-Meinesz (IVM). The computed gravity anomaly models then assessed with the in-situ marine gravity data from the National Geophysical Data Center (NGDC). The best model in term of RMS error is the 10 km Gaussian filtered LSC with an RMS error of 15.042 mgal. The least accurate model is the non-filtered IVM with an RMS of 16.704 mgal.
Pembuatan Peta RBI skala 1:5.000 membutuhkan waktu yang lama, khususnya untuk pembuatan layer kon... more Pembuatan Peta RBI skala 1:5.000 membutuhkan waktu yang lama, khususnya untuk pembuatan layer kontur. Layer kontur bisa didapatkan dari data hasil ekstraksi foto udara dan data Light Detection and Ranging (LIDAR). Sekarang ini, teknologi LiDAR lebih diandalkan untuk membuat Data Surface Model (DSM). Dari DSM dilakukan proses ekstrasi data untuk mendapatkan data Digital Terrain Model (DTM) atau Digital Elevation Model (DEM) yang prosesnya lebih cepat dan membutuhkan biaya yang relatif rendah. Metode filtering yang digunakan adalah metode Simple Morphological Filtering (SMRF) dengan memasukkan nilai parameter cell size, slope, windows, elevation threshold dan scalling factor. Hasil Cohen’s kappa rata-rata menunjukkan indikator DTM dalam kondisi baik, yang artinya dengan menggunakan metode SMRF, nilai kappa berada diantara 0,4-0,7. Smoothing filter dilakukan untuk menghilangkan sel kosong/ sel tanpa data. DTM yang dihasilkan dibandingkan dengan data validasi lapangan. Root Mean Square ...
Transportation Research Record: Journal of the Transportation Research Board, 2019
The purpose of this study is to investigate and identify the waste from the unloading station of ... more The purpose of this study is to investigate and identify the waste from the unloading station of mineral cars using the lean thinking approach. In this paper, one of the largest steel producers is investigated as a case study. The time information was collected from the database system of the factory and railway company from April to July 2017. The wastes were identified by using the value stream map, and to reduce the waste, ten solutions have been proposed based on the changes in: (a) operation management; (b) purchase of new equipment; and (c) infrastructure development. Implementation of solutions using the Planimate simulator software shows that the best strategy consists of a combination of three operational management solutions without having to purchase new equipment and without any infrastructure development, which can improve station performance by up to 52% with regards to the total time for the unloading process. In addition, the valuable time of the whole process has be...
Pengukuran gayaberat absolut merupakan pengukuran nilai gayaberat dengan mengamati percepatan ver... more Pengukuran gayaberat absolut merupakan pengukuran nilai gayaberat dengan mengamati percepatan vertikal benda jatuh bebas. Pada tahun 2017, Badan Informasi Geospasial (BIG) melakukan pengukuran gayaberat absolut di beberapa pilar Gayaberat Utama (GBU) di Indonesia dengan menggunakan gravimeter A-10. Tujuan penulisan makalah ini adalah memaparkan teknik pengukuran dan pengolahan data gayaberat absolut di GBU yang merupakan bagian dari Jaring Kontrol Gayaberat (JKG) dengan menggunakan gravimeter A-10. Titik-titik yang akan dijadikan pembahasan dalam makalah ini adalah GBU018 di Jakarta dan GBU035 di Makassar. Pengukuran di tiap titik dilakukan sebanyak 10 set dengan jumlah drop untuk setiap set sebanyak 120. Hasil yang diperoleh adalah nilai gayaberat absolut (µgal) beserta ketidakpastiannya. Nilai gayaberat (g) hasil pengolahan di lapangan (on-site) untuk GBU018 adalah 978140735,73 ± 11,17 µgal, sedangkan untuk GBU035 adalah 978117560,92 ± 7,16 µgal. Nilai-nilai tersebut diperoleh set...
Satelit altimetri merupakan satelit yang memiliki fungsi utama untuk mengamati topografi dan dina... more Satelit altimetri merupakan satelit yang memiliki fungsi utama untuk mengamati topografi dan dinamika permukaan laut. Namun satelit ini memiliki kelemahan, salah satunya adalah pengamatan permukaan laut di wilayah pesisir. Keberadaan daratan di wilayah pesisir disertai kedalaman perairan yang relatif dangkal membuat pengamatan satelit altimetri tidak sebaik di laut lepas. Hal ini tentunya sangat merugikan mengingat pentingnya peranan wilayah pesisir bagi kehidupan umat manusia. Untuk mengatasi rendahnya kualitas pengamatan satelit altimetri di wilayah pesisir, dewasa ini marak dikembangkan penelitian mengenai coastal atimetry. Salah satu penelitian tersebut adalah waveform retracking atau pengolahan ulang gelombang pantul hasil pengamatan satelit altimetri. Dalam proses waveform retracking, identifikasi waveform yang terkontaminasi merupakan langkah awal yang paling penting. Pada Tugas Akhir ini dilakukan proses identifikasi beserta analisis terhadap waveform satelit Jason-2 (salah satu satelit altimetri) di wilayah pesisir Pulau Sulawesi, Indonesia. Berdasarkan hasil identifikasi terhadap data waveform satelit Jason-2 (digunakan 8 set data yang teridiri dari 5 pass dalam 2 cycle), diperoleh informasi bahwa jarak 0-5 km dari bibir pantai merupakan jarak dengan tingkat kontaminasi yang tinggi. Selain itu kedalaman perairan yang kurang dari 200 m juga menjadi penyebab utama tingginya tingkat kontaminasi waveform altimetri di wilayah pesisir.
Topographic mapping using stereo plotting is not effective because it takes much time and labor-i... more Topographic mapping using stereo plotting is not effective because it takes much time and labor-intensive. Thus, this research was conducted to find the effective way to extract building footprint for mapping acceleration. Building extraction method in this process comprises four steps: ground / non-ground filtering, building classification, segmentation, and building extraction. Non-ground points from filtering process were classified as building with the algorithm based on multi-scale local dimensionality to separate points at the maximum separability plane. Segmentation using segment growing was used to separate each building, so edge detection could be conducted for each segment to create boundary of each building. Lastly, building extraction was conducted through three steps: edge points detection, building delineation, and building regularization. With 10 samples and step 0.5, classification resulted quality and miss factor of 0.597 and 0.524, respectively. The quality was imp...
Indonesia is an archipelago country where 77% of its territory is waters. National marine mapping... more Indonesia is an archipelago country where 77% of its territory is waters. National marine mapping has been carried out based on depth measurement data obtained using echosounders. However, this method requires a lot of time and cost. One solution to provide Indonesian bathymetry data is by utilizing altimetry satellite data to model the bathymetry of the seafloor. This study aims to evaluate bathymetric model generated from three combinations of five altimetry satellites in shallow and deep seas. We use least square collocation gravity anomaly and geological gravity for bathymetry modeling. The results of the model show variations in deviations with sounding data available at the Geospatial Information Agency (BIG) . The resulting residual trend differs between shallow and deep sea. The optimum results in shallow area is obtained by the combination of Cryosat-2, Jason-1/C, and SARAL while in deep area is obtained by the combination of ERS-1/E-F and Geosat GM. In general, the bathyme...
Teknologi kecerdasan buatan adalah sebuah inovasi mutakhir yang mengandalkan peran komputer untuk... more Teknologi kecerdasan buatan adalah sebuah inovasi mutakhir yang mengandalkan peran komputer untuk mengenali dan memprediksi berbagai objek yang menjadi perhatian, dalam hal ini adalah fitur bangunan pada peta Rupabumi Indonesia (RBI) skala besar. Teknologi ini memiliki cakupan yang sangat luas, dan dalam penelitian ini akan dibahas aplikasi salah satu cabang kecerdasan buatan yang paling kompleks, yakni deep learning. Metode deep learning yang digunakan dalam ekstraksi fitur bangunan pada peta RBI skala besar adalah semantic segmentation, dimana objek tidak hanya dideteksi, namun juga disegmentasi bagian tepinya tanpa memperhatikan unit satuan bangunan sehingga diperoleh hasil-hasil berupa fitur bangunan dalam satu kesatuan segmen dan fitur selain bangunan menjadi segmen lainnya. Algoritma semantic segmentation yang dipilih adalah Unet yang dibagi ke dalam arsitektur Small Unet dan Full Unet. Arsitektur Small Unet menggunakan 18 layer konvolusi sedangkan Full Unet menggunakan 19 lay...
Topographic mapping using stereo plotting is not effective, because it takes much time and labour... more Topographic mapping using stereo plotting is not effective, because it takes much time and labour-intensive. Thus, this research was conducted to find the effective way to extract building footprint for mapping acceleration from LiDAR data. Building extraction method in this process comprises four steps: ground/non-ground filtering, building classification, segmentation, and building extraction. Classification of ground and non-ground classes was performed using Adaptive-TIN Surface algorithm. Non-ground points from filtering process were classified as building with the algorithm based on multiscale local dimensionality to separate points at the maximum separability plane. Segmentation using segment growing was used to separate each building, so boundary detection could be conducted for each segment to create boundary of each building. Lastly, building extraction was conducted through three steps: boundary point detection, building delineation, and building regularization. With ten ...
ABSTRAK Wilayah Samudera Pasifik bagian barat merupakan salah satu wilayah yang mengalami kenaika... more ABSTRAK Wilayah Samudera Pasifik bagian barat merupakan salah satu wilayah yang mengalami kenaikan muka laut tertinggi di dunia. Data satelit altimetri Topex/Poseidon Jason 1 dan Jason 2, pada kurun waktu tahun 1992-2012, menunjukkan rata-rata kenaikan muka laut di area ini adalah 6,982 ± 3,493 mm/tahun. Sebagai pembanding, perubahan muka laut di wilayah ini pun dihitung berdasarkan data suhu dan salinitas dari pelampung Argo. Data suhu dan salinitas yang digunakan berada pada rentang waktu tahun 2000 – 2013. Perubahan tinggi muka laut berdasarkan data pelampung Argo adalah 14,352 ±13.002 mm/tahun. Tinggi muka laut ini merupakan komponen sterik dari total perubahan muka air laut. Tinggi sterik muka air laut merupakan ketebalan vertikal di atas sebuah lapisan ketebalan h dari anomali volume tertentu dan dapat dihubungkan dengan medan densitas lautan. Berdasarkan hasil penelitian ini, maka dapat disimpulkan bahwa ekspansi termal lautan merupakan penyebab utama perubahan/kenaikan muka ...
Satellite imagery along with image processing techniques are essential tools for bathymetry retri... more Satellite imagery along with image processing techniques are essential tools for bathymetry retrieval since they are relatively inexpensive in term of time and budget in comparison to the conventional bathymetry survey. Approximately, 1126 bathymetric maps in various scales were produced by Badan Informasi Geospasial (BIG) covering Indonesia’s oceans and coastal waters. Those maps actually only cover 24,9% of total maps required to cover all Indonesia waters. Moreover, gaps in survey data, particularly in shallow water area, are also problematic. Only 12% of Indonesia’s waters are covered by a detailed survey. Hence, BIG is exploring remote sensing techniques to help with the improvement of Indonesia’s bathymetric maps including Satellite-Derived Bathymetry (SDB). SDB is promising due to its ability to fill the gap of depths derived from conventional hydrographic surveys. This is important for BIG since achieving wide-area depth coverage via the hydrographic surveys is costly in ter...
ABSTRAK Metode Precise Point Positionin g (PPP) adalah metode penentuan posisi teliti yang hanya ... more ABSTRAK Metode Precise Point Positionin g (PPP) adalah metode penentuan posisi teliti yang hanya menggunakan sebuah receiver GNSS dual frekuensi. Metode ini dapat digunakan untuk menentukan posisi teliti objek-objek yang diam ( static ) maupun bergerak ( kinematic ). Pada penelitian ini, akan dipaparkan mengenai penggunaan kinematik PPP dalam penentuan posisi pesawat terbang pada survei gayaberat airborne di Sulawesi tahun 2008. Data yang digunakan adalah jalur terbang pesawat pada day of year (DOY) 291 dan 274. Perangkat lunak yang digunakan adalah Waypoint ® Grafnav. Hasil pengolahan menggunakan metode PPP tersebut kemudian dibandingkan dengan hasil pengolahan data Diferensial GPS (DGPS) dengan 1 titik ikat untuk DOY 291 dan 2 titik ikat untuk DOY 274. Hasil perbandingan pada DOY 291 menunjukkan nilai RMS untuk arah timur, utara dan tinggi masing-masing sebesar 0,024 m; 0,020 m dan 0,039 m. Pada DOY 274, RMS yang diperoleh adalah 0,032 m; 0,011 m dan 0,058 m masing-masing untuk arah timur, utara dan tinggi. Hasil-hasil tersebut mengindikasikan bahwa metode PPP dapat digunakan untuk menentukan posisi pesawat terbang dengan fraksi ketelitian sentimeter. Tingkat ketelitian posisi ini sudah memenuhi syarat untuk digunakan pada survei gayaberat airborne . Kata kunci : GNSS, kinematik PPP, gayaberat airborne, DGPS ABSTRACT The Precise Point Positioning (PPP) is a positioning method which only use a dual frequency GNSS receiver. This method can be used to determine the precise position of either static (static) or moving objects (kinematic). In this paper, we will discuss the application of kinematic PPP for the 2008 Sulawesi airborne gravity survey. By using a commercial GNSS processing software called Waypoint® Grafnav, we determine the PPP solutions for the aircraft trajectory of the day of year (DOY) 291 and 274. Each solution then be compared to the Differential GPS (DGPS) results, which use one base station for DOY 291 and two reference stations for DOY 274. The PPP solution of DOY 291 gives RMS error of 0.024 m eastward, 0.020 m northward, and 0.039 m upward. Moreover, the comparison of DOY 274 gives RMS error of 0.032 m eastward, 0.011 m northward, and 0.058 m upward. These centimeter level RMS errors show that PPP is a compatible positioning method for airborne gravity survey. Keywords : GNSS, k inematic PPP, airborne gravity, DGPS
. The change of sea level in the western Pasific Ocean is one of the biggest change in the world.... more . The change of sea level in the western Pasific Ocean is one of the biggest change in the world. This is caused by steric and eustatic factors. In the period of 1992-2012, the total change of sea level in this area based on the Topex/Poseidon satellite data, Jason 1 and Jason 2, was 6. 982 ± 3 . 493 mm/ year. Based on the temperature and salinity from Argo floats for the period 2000 – 2013, the obtained high streic changes in sea level in the region is about 14.352 ± 13.002 mm/ year. The result is a based on high steric sea level relative to 900 dbar pressure. To find the rise of eustatic sea level that caused by the changes in ocean mass, linear regression performed on the data Equivalent Water Thickness (EWT) of monthly GRACE satellites in the period January 2004 to April 2013. The magnitude of the linear trend EWT changes in this area is -0 . 4026 ± 0 . 1073 mm/ year. This study concludes that the correlation between EWT and the SLA value is more significant than the correlatio...
Coastline Modeling Accuracy Assessment Developed By Using from Multi-Source Data. The coastal reg... more Coastline Modeling Accuracy Assessment Developed By Using from Multi-Source Data. The coastal regions need to be developed because many big cities in Indonesia are located in these areas. However, it is crucial to determine the distance from the beach that is safe as the requirement for development along the coastal zone. The term of the beach is very closely affiliated with the coastline. The method of determining the coastline continues to be developed to fulfill the many needs related to the coastline. The coastline has a dynamic position. The land contour along the coast and the tide's state become several things that affect the coastline. Therefore, a dynamic model is required to define coastline positioning because both conditions are easy to change. The coastline determination from multi-source data modeling using DEM results is rarely done. In this study, coastline determination uses land height contours combined with sea depth contours and uses Mean Sea Level (MSL) valu...
IOP Conference Series: Earth and Environmental Science, 2021
To use the Global Navigation Satellite System (GNSS) correctly, the height information should be ... more To use the Global Navigation Satellite System (GNSS) correctly, the height information should be transformed into orthometric height by subtracting geoid undulation from it. This orthometric height is commonly used for practical purposes. In 2015 geoid of Jakarta has been produced, and it has an accuracy of 0.076 m. In the year 2019, airborne gravimetry has been done for the entire Java Island. The area of DKI Province cannot be measured because there is inhibition from Airnav. For this reason, terrestrial gravimetric measurements are carried out in this region by adding points outside the previously measured area. To compute the geoid in the Jakarta region is needed the Global Geopotential Model (GGM). In this paper, the GMM used is gif48. The “remove and restore” method will be used in calculating the geoid in this Jakarta region. Besides that in this geoid calculation also uses Stokes kernel and FFT to speed up the calculation. The verification of the resulting geoid is carried w...
IOP Conference Series: Earth and Environmental Science, Jun 1, 2018
Nowadays satellite altimetry has become an advanced instrument to observe many natural physical p... more Nowadays satellite altimetry has become an advanced instrument to observe many natural physical phenomena, such as sea-level rise, ocean circulation, water mass changes, and marine gravity anomaly. The use of satellite altimetry data to compute marine gravity anomaly provides good results and costs relatively low. Those advantages make geodesists utilize this method as an alternative in geoid determination, especially over the seas. Several sets of satellite altimetry data from Cryosat 2, Jason 1 phase C, Geosat and ERS1 were used to compute gravity anomaly over the surrounding waters of Kalimantan and Sulawesi Island in Indonesia. The study area spans between -7°-7° N and 108°-127° E with a spatial resolution of 1'x1'. In the pre-processing step, the altimetry data especially Geosat and ERS1, were retracked to reduce errors due to the land influence. The main computation step was done by using two different methods, least square collocation (LSC) and Inverse Vening-Meinesz (IVM). The computed gravity anomaly models then assessed with the in-situ marine gravity data from the National Geophysical Data Center (NGDC). The best model in term of RMS error is the 10 km Gaussian filtered LSC with an RMS error of 15.042 mgal. The least accurate model is the non-filtered IVM with an RMS of 16.704 mgal.
Pembuatan Peta RBI skala 1:5.000 membutuhkan waktu yang lama, khususnya untuk pembuatan layer kon... more Pembuatan Peta RBI skala 1:5.000 membutuhkan waktu yang lama, khususnya untuk pembuatan layer kontur. Layer kontur bisa didapatkan dari data hasil ekstraksi foto udara dan data Light Detection and Ranging (LIDAR). Sekarang ini, teknologi LiDAR lebih diandalkan untuk membuat Data Surface Model (DSM). Dari DSM dilakukan proses ekstrasi data untuk mendapatkan data Digital Terrain Model (DTM) atau Digital Elevation Model (DEM) yang prosesnya lebih cepat dan membutuhkan biaya yang relatif rendah. Metode filtering yang digunakan adalah metode Simple Morphological Filtering (SMRF) dengan memasukkan nilai parameter cell size, slope, windows, elevation threshold dan scalling factor. Hasil Cohen’s kappa rata-rata menunjukkan indikator DTM dalam kondisi baik, yang artinya dengan menggunakan metode SMRF, nilai kappa berada diantara 0,4-0,7. Smoothing filter dilakukan untuk menghilangkan sel kosong/ sel tanpa data. DTM yang dihasilkan dibandingkan dengan data validasi lapangan. Root Mean Square ...
Transportation Research Record: Journal of the Transportation Research Board, 2019
The purpose of this study is to investigate and identify the waste from the unloading station of ... more The purpose of this study is to investigate and identify the waste from the unloading station of mineral cars using the lean thinking approach. In this paper, one of the largest steel producers is investigated as a case study. The time information was collected from the database system of the factory and railway company from April to July 2017. The wastes were identified by using the value stream map, and to reduce the waste, ten solutions have been proposed based on the changes in: (a) operation management; (b) purchase of new equipment; and (c) infrastructure development. Implementation of solutions using the Planimate simulator software shows that the best strategy consists of a combination of three operational management solutions without having to purchase new equipment and without any infrastructure development, which can improve station performance by up to 52% with regards to the total time for the unloading process. In addition, the valuable time of the whole process has be...
Pengukuran gayaberat absolut merupakan pengukuran nilai gayaberat dengan mengamati percepatan ver... more Pengukuran gayaberat absolut merupakan pengukuran nilai gayaberat dengan mengamati percepatan vertikal benda jatuh bebas. Pada tahun 2017, Badan Informasi Geospasial (BIG) melakukan pengukuran gayaberat absolut di beberapa pilar Gayaberat Utama (GBU) di Indonesia dengan menggunakan gravimeter A-10. Tujuan penulisan makalah ini adalah memaparkan teknik pengukuran dan pengolahan data gayaberat absolut di GBU yang merupakan bagian dari Jaring Kontrol Gayaberat (JKG) dengan menggunakan gravimeter A-10. Titik-titik yang akan dijadikan pembahasan dalam makalah ini adalah GBU018 di Jakarta dan GBU035 di Makassar. Pengukuran di tiap titik dilakukan sebanyak 10 set dengan jumlah drop untuk setiap set sebanyak 120. Hasil yang diperoleh adalah nilai gayaberat absolut (µgal) beserta ketidakpastiannya. Nilai gayaberat (g) hasil pengolahan di lapangan (on-site) untuk GBU018 adalah 978140735,73 ± 11,17 µgal, sedangkan untuk GBU035 adalah 978117560,92 ± 7,16 µgal. Nilai-nilai tersebut diperoleh set...
Satelit altimetri merupakan satelit yang memiliki fungsi utama untuk mengamati topografi dan dina... more Satelit altimetri merupakan satelit yang memiliki fungsi utama untuk mengamati topografi dan dinamika permukaan laut. Namun satelit ini memiliki kelemahan, salah satunya adalah pengamatan permukaan laut di wilayah pesisir. Keberadaan daratan di wilayah pesisir disertai kedalaman perairan yang relatif dangkal membuat pengamatan satelit altimetri tidak sebaik di laut lepas. Hal ini tentunya sangat merugikan mengingat pentingnya peranan wilayah pesisir bagi kehidupan umat manusia. Untuk mengatasi rendahnya kualitas pengamatan satelit altimetri di wilayah pesisir, dewasa ini marak dikembangkan penelitian mengenai coastal atimetry. Salah satu penelitian tersebut adalah waveform retracking atau pengolahan ulang gelombang pantul hasil pengamatan satelit altimetri. Dalam proses waveform retracking, identifikasi waveform yang terkontaminasi merupakan langkah awal yang paling penting. Pada Tugas Akhir ini dilakukan proses identifikasi beserta analisis terhadap waveform satelit Jason-2 (salah satu satelit altimetri) di wilayah pesisir Pulau Sulawesi, Indonesia. Berdasarkan hasil identifikasi terhadap data waveform satelit Jason-2 (digunakan 8 set data yang teridiri dari 5 pass dalam 2 cycle), diperoleh informasi bahwa jarak 0-5 km dari bibir pantai merupakan jarak dengan tingkat kontaminasi yang tinggi. Selain itu kedalaman perairan yang kurang dari 200 m juga menjadi penyebab utama tingginya tingkat kontaminasi waveform altimetri di wilayah pesisir.
Topographic mapping using stereo plotting is not effective because it takes much time and labor-i... more Topographic mapping using stereo plotting is not effective because it takes much time and labor-intensive. Thus, this research was conducted to find the effective way to extract building footprint for mapping acceleration. Building extraction method in this process comprises four steps: ground / non-ground filtering, building classification, segmentation, and building extraction. Non-ground points from filtering process were classified as building with the algorithm based on multi-scale local dimensionality to separate points at the maximum separability plane. Segmentation using segment growing was used to separate each building, so edge detection could be conducted for each segment to create boundary of each building. Lastly, building extraction was conducted through three steps: edge points detection, building delineation, and building regularization. With 10 samples and step 0.5, classification resulted quality and miss factor of 0.597 and 0.524, respectively. The quality was imp...
Indonesia is an archipelago country where 77% of its territory is waters. National marine mapping... more Indonesia is an archipelago country where 77% of its territory is waters. National marine mapping has been carried out based on depth measurement data obtained using echosounders. However, this method requires a lot of time and cost. One solution to provide Indonesian bathymetry data is by utilizing altimetry satellite data to model the bathymetry of the seafloor. This study aims to evaluate bathymetric model generated from three combinations of five altimetry satellites in shallow and deep seas. We use least square collocation gravity anomaly and geological gravity for bathymetry modeling. The results of the model show variations in deviations with sounding data available at the Geospatial Information Agency (BIG) . The resulting residual trend differs between shallow and deep sea. The optimum results in shallow area is obtained by the combination of Cryosat-2, Jason-1/C, and SARAL while in deep area is obtained by the combination of ERS-1/E-F and Geosat GM. In general, the bathyme...
Teknologi kecerdasan buatan adalah sebuah inovasi mutakhir yang mengandalkan peran komputer untuk... more Teknologi kecerdasan buatan adalah sebuah inovasi mutakhir yang mengandalkan peran komputer untuk mengenali dan memprediksi berbagai objek yang menjadi perhatian, dalam hal ini adalah fitur bangunan pada peta Rupabumi Indonesia (RBI) skala besar. Teknologi ini memiliki cakupan yang sangat luas, dan dalam penelitian ini akan dibahas aplikasi salah satu cabang kecerdasan buatan yang paling kompleks, yakni deep learning. Metode deep learning yang digunakan dalam ekstraksi fitur bangunan pada peta RBI skala besar adalah semantic segmentation, dimana objek tidak hanya dideteksi, namun juga disegmentasi bagian tepinya tanpa memperhatikan unit satuan bangunan sehingga diperoleh hasil-hasil berupa fitur bangunan dalam satu kesatuan segmen dan fitur selain bangunan menjadi segmen lainnya. Algoritma semantic segmentation yang dipilih adalah Unet yang dibagi ke dalam arsitektur Small Unet dan Full Unet. Arsitektur Small Unet menggunakan 18 layer konvolusi sedangkan Full Unet menggunakan 19 lay...
Topographic mapping using stereo plotting is not effective, because it takes much time and labour... more Topographic mapping using stereo plotting is not effective, because it takes much time and labour-intensive. Thus, this research was conducted to find the effective way to extract building footprint for mapping acceleration from LiDAR data. Building extraction method in this process comprises four steps: ground/non-ground filtering, building classification, segmentation, and building extraction. Classification of ground and non-ground classes was performed using Adaptive-TIN Surface algorithm. Non-ground points from filtering process were classified as building with the algorithm based on multiscale local dimensionality to separate points at the maximum separability plane. Segmentation using segment growing was used to separate each building, so boundary detection could be conducted for each segment to create boundary of each building. Lastly, building extraction was conducted through three steps: boundary point detection, building delineation, and building regularization. With ten ...
ABSTRAK Wilayah Samudera Pasifik bagian barat merupakan salah satu wilayah yang mengalami kenaika... more ABSTRAK Wilayah Samudera Pasifik bagian barat merupakan salah satu wilayah yang mengalami kenaikan muka laut tertinggi di dunia. Data satelit altimetri Topex/Poseidon Jason 1 dan Jason 2, pada kurun waktu tahun 1992-2012, menunjukkan rata-rata kenaikan muka laut di area ini adalah 6,982 ± 3,493 mm/tahun. Sebagai pembanding, perubahan muka laut di wilayah ini pun dihitung berdasarkan data suhu dan salinitas dari pelampung Argo. Data suhu dan salinitas yang digunakan berada pada rentang waktu tahun 2000 – 2013. Perubahan tinggi muka laut berdasarkan data pelampung Argo adalah 14,352 ±13.002 mm/tahun. Tinggi muka laut ini merupakan komponen sterik dari total perubahan muka air laut. Tinggi sterik muka air laut merupakan ketebalan vertikal di atas sebuah lapisan ketebalan h dari anomali volume tertentu dan dapat dihubungkan dengan medan densitas lautan. Berdasarkan hasil penelitian ini, maka dapat disimpulkan bahwa ekspansi termal lautan merupakan penyebab utama perubahan/kenaikan muka ...
Satellite imagery along with image processing techniques are essential tools for bathymetry retri... more Satellite imagery along with image processing techniques are essential tools for bathymetry retrieval since they are relatively inexpensive in term of time and budget in comparison to the conventional bathymetry survey. Approximately, 1126 bathymetric maps in various scales were produced by Badan Informasi Geospasial (BIG) covering Indonesia’s oceans and coastal waters. Those maps actually only cover 24,9% of total maps required to cover all Indonesia waters. Moreover, gaps in survey data, particularly in shallow water area, are also problematic. Only 12% of Indonesia’s waters are covered by a detailed survey. Hence, BIG is exploring remote sensing techniques to help with the improvement of Indonesia’s bathymetric maps including Satellite-Derived Bathymetry (SDB). SDB is promising due to its ability to fill the gap of depths derived from conventional hydrographic surveys. This is important for BIG since achieving wide-area depth coverage via the hydrographic surveys is costly in ter...
ABSTRAK Metode Precise Point Positionin g (PPP) adalah metode penentuan posisi teliti yang hanya ... more ABSTRAK Metode Precise Point Positionin g (PPP) adalah metode penentuan posisi teliti yang hanya menggunakan sebuah receiver GNSS dual frekuensi. Metode ini dapat digunakan untuk menentukan posisi teliti objek-objek yang diam ( static ) maupun bergerak ( kinematic ). Pada penelitian ini, akan dipaparkan mengenai penggunaan kinematik PPP dalam penentuan posisi pesawat terbang pada survei gayaberat airborne di Sulawesi tahun 2008. Data yang digunakan adalah jalur terbang pesawat pada day of year (DOY) 291 dan 274. Perangkat lunak yang digunakan adalah Waypoint ® Grafnav. Hasil pengolahan menggunakan metode PPP tersebut kemudian dibandingkan dengan hasil pengolahan data Diferensial GPS (DGPS) dengan 1 titik ikat untuk DOY 291 dan 2 titik ikat untuk DOY 274. Hasil perbandingan pada DOY 291 menunjukkan nilai RMS untuk arah timur, utara dan tinggi masing-masing sebesar 0,024 m; 0,020 m dan 0,039 m. Pada DOY 274, RMS yang diperoleh adalah 0,032 m; 0,011 m dan 0,058 m masing-masing untuk arah timur, utara dan tinggi. Hasil-hasil tersebut mengindikasikan bahwa metode PPP dapat digunakan untuk menentukan posisi pesawat terbang dengan fraksi ketelitian sentimeter. Tingkat ketelitian posisi ini sudah memenuhi syarat untuk digunakan pada survei gayaberat airborne . Kata kunci : GNSS, kinematik PPP, gayaberat airborne, DGPS ABSTRACT The Precise Point Positioning (PPP) is a positioning method which only use a dual frequency GNSS receiver. This method can be used to determine the precise position of either static (static) or moving objects (kinematic). In this paper, we will discuss the application of kinematic PPP for the 2008 Sulawesi airborne gravity survey. By using a commercial GNSS processing software called Waypoint® Grafnav, we determine the PPP solutions for the aircraft trajectory of the day of year (DOY) 291 and 274. Each solution then be compared to the Differential GPS (DGPS) results, which use one base station for DOY 291 and two reference stations for DOY 274. The PPP solution of DOY 291 gives RMS error of 0.024 m eastward, 0.020 m northward, and 0.039 m upward. Moreover, the comparison of DOY 274 gives RMS error of 0.032 m eastward, 0.011 m northward, and 0.058 m upward. These centimeter level RMS errors show that PPP is a compatible positioning method for airborne gravity survey. Keywords : GNSS, k inematic PPP, airborne gravity, DGPS
. The change of sea level in the western Pasific Ocean is one of the biggest change in the world.... more . The change of sea level in the western Pasific Ocean is one of the biggest change in the world. This is caused by steric and eustatic factors. In the period of 1992-2012, the total change of sea level in this area based on the Topex/Poseidon satellite data, Jason 1 and Jason 2, was 6. 982 ± 3 . 493 mm/ year. Based on the temperature and salinity from Argo floats for the period 2000 – 2013, the obtained high streic changes in sea level in the region is about 14.352 ± 13.002 mm/ year. The result is a based on high steric sea level relative to 900 dbar pressure. To find the rise of eustatic sea level that caused by the changes in ocean mass, linear regression performed on the data Equivalent Water Thickness (EWT) of monthly GRACE satellites in the period January 2004 to April 2013. The magnitude of the linear trend EWT changes in this area is -0 . 4026 ± 0 . 1073 mm/ year. This study concludes that the correlation between EWT and the SLA value is more significant than the correlatio...
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Papers by prayudha hartanto