ORCID Profile
0000-0002-1720-884X
Current Organisation
Badan Riset dan Inovasi Nasional Republik Indonesia
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Publisher: Copernicus GmbH
Date: 04-06-2019
DOI: 10.5194/ISPRS-ARCHIVES-XLII-2-W13-27-2019
Abstract: Abstract. The ersity and heterogeneity of coastal, estuarine and stream habitats has led to them becoming a prevalent topic for study. Woody ruins are areas of potential riverbed habitat, particularly for fish. Therefore, the mapping of those areas is of interest. However, due to the limited visibility in some river systems, satellites, airborne or other camera-based systems (passive systems) cannot be used. By contrast, sidescan sonar is a popular underwater acoustic imaging system that is capable of providing high- resolution monochromatic images of the seafloor and riverbeds. Although the study of sidescan sonar imaging using supervised classification has become a prominent research subject, the use of composite texture features in machine learning classification is still limited. This study describes an investigation of the use of texture analysis and feature extraction on side-scan sonar imagery in two supervised machine learning classifications: Support Vector Machine (SVM) and Decision Tree (DT). A combination of first- order texture and second-order texture is investigated to obtain the most appropriate texture features for the image classification. SVM, using linear and Gaussian kernels along with Decision Tree classifiers, was examined using selected texture features. The results of overall accuracy and kappa coefficient revealed that SVM using a linear kernel leads to a more promising result, with 77% overall accuracy and 0.62 kappa, than SVM using either a Gaussian kernel or Decision Tree (60% and 73% overall accuracy, and 0.39 and 0.59 kappa, respectively). However, this study has demonstrated that SVM using linear and Gaussian kernels as well as a Decision Tree makes it capable of being used in side-scan sonar image classification and riverbed habitat mapping.
Publisher: Universitas Gadjah Mada
Date: 30-06-2018
DOI: 10.22146/IJG.30149
Abstract: Exploratory Analysis as one of the spatial analysis tools that has been used widely in many study fields. This tool is usually intended to obtain the spatial pattern to observe and get relationship between study variables. The exploratory analysis is usually followed by the confirmatory analysis to exhibit the hypothesis that already obtain in the exploratory analysis. This study is aimed to investigate the prevalence of asthma in Western Australia since there are many factors that cause the asthma dispersion. Many provided variables have been tested to get the best correlation with the asthma percentage variable and four variables (humidity, annual rainfall, EVI and SEIFA) were chosen and tested with high asthma percentage variable. The result of confirmatory analysis indicates that the high level of humidity and low level of SEIFA confirm with the hypothesis and means that those factors can contribute significantly in Asthma prevalence in Western Australia.
Publisher: Badan Pengkajian dan Penerapan Teknologi (BPPT)
Date: 29-04-2020
DOI: 10.29122/OSEANIKA.V1I1.4053
Abstract: River and estuary areas commonly exhibit complex and heterogeneous habitats. Thus, revealing the distribution of riverbed morphologies could promote the area management and habitats protection. Since the remote sensing method and manual survey are limited to use, side-scan sonar performs an expectant outcome in underwater habitat imaging. In shallow water and stream areas, low-cost side-scan sonar imaging has become a notable subject of study, yet its use in Indonesia is still limited. This study describes an investigation of the use of a recreational-grade side-scan sonar for stream underwater imaging. A visual inspection and interpretation were implemented using a free-cost sonar software. The result shows some underwater objects and debris could be portrayed perfectly and this indicates that the inexpensive sonar system is appropriate to be used in shallow water and stream areas with a non-rough sea surface. It is suggested that this system could provide a satisfactory product to the users who do not require high accuracy and high resolution of riverbed imagery.Keywords: estuary, river, underwater mapping, acoustic remote sensing, low-cost, side-scan sonar.
Publisher: Badan Pengkajian dan Penerapan Teknologi (BPPT)
Date: 31-12-2020
DOI: 10.29122/OSEANIKA.V1I2.4529
Abstract: Kepulauan Raja Ampat merupakan salah satu tujuan wisata utama di Indonesia dan juga sebagai kawasan konservasi alam. Hal tersebut disebabkan karena wilayah tersebut kaya akan keanekaragaman hayati, ken akan dan sumber daya alam, serta budaya. Pada tahun 2014, pemerintah Indonesia menyelenggarakan kegiatan Sail Raja Ampat sebagai bagian promosi pembangunan di wilayah tersebut. Badan Pengkajian dan Penerapan Teknologi (BPPT) berperan dalam kegiatan Sail tersebut dengan menggunakan KR Baruna Jaya IV untuk melakukan survei kelautan maupun kegiatan diseminasi teknologi. Penelitian ini bertujuan untuk memberikan gambaran kegiatan survei hidro-oseanografi di perairan Raja Ampat sebagai bagian kegiatan Sail Raja Ampat. Kegiatan survei dilakukan pada dua area utama yaitu Teluk Kabui dan Selat Sagewin. Hasil menunjukkan bahwa survei tersebut m u memberikan gambaran morfologi di kedua area tersebut. Secara batimetri perairan Teluk Kabui memiliki kedalaman antara 18 – 53 meter, sedangkan kedalaman perairan Selat Sagewin berkisar antara 104 - 508 meter. Rata – rata suhu di perairan Raja Ampat diketahui berkisar antara 28? – 29?C dan memiliki salinitas berkisar antara 32.5 - 35 psu. Litologi berupa batupasir, batug ing, dan lempung juga berhasil diketahui dari survei tersebut. Data – data ilmiah kebumian tersebut bermanfaat untuk melengkapi data – data yang sudah ada ataupun sebagai dasar perencanaan kegiatan penelitian selanjutnya. Dis ing itu, data tersebut dapat dimanfaatkan untuk mengetahui karakteristik alam di perairan Raja Ampat sebagai pendukung kegiatan pembangunan di wilayah tersebut.
Location: Indonesia
Location: Indonesia
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