Judul: Marine Basic Spatial Unit Grid Optimization for Ecosystem Extent in Ocean Accounts
Abstrak: Luasan ekosistem merupakan salah satu struktur dalam Neraca Sumberdaya Laut yang diukur dalam satuan luasan spasial dengan grid MBSU. Penelitian ini bertujuan menentukan ukuran grid dan teknik gridding MBSU optimal untuk perhitungan luasan ekosistem perairan Indonesia (Teluk Saleh). Analisis spasial dengan coarse-graining digunakan untuk membandingkan 4 (empat) skema pemrosesan grid. Persen error dari luasan ekosistem hasil teknik hierarki berada di kisaran 7,54-44,06%, sedangkan teknik dominansi 1,46-2,20%. Skema dengan teknik dominansi memperoleh perbedaan hasil antara ukuran grid 10x10 meter dan 25x25 meter tidak berbeda nyata, dibuktikan dengan p-value 0,479, 0,239, dan 0,329 untuk ekosistem mangrove, lamun, dan terumbu karang. Uji akurasi memperoleh overall accuracy di atas 85% untuk teknik dominansi baik ukuran 10x10 meter maupun 25x25 meter, sehingga hasil keduanya dianggap baik. Dominansi merupakan teknik pemrosesan MBSU yang lebih optimal, baik menggunakan ukuran grid 10x10 meter maupun 25x25 meter, namun jika mempertimbangkan lama waktu pemrosesan, grid 25x25 meter lebih efisien., Ecosystem extent is one of the structures in Ocean Accounts, which is measured in spatial units using the MBSU grid. This study aimed to determine the optimal MBSU grid size and gridding technique for ecosystem extent of Indonesian waters (Saleh Bay). Coarse-graining spatial analysis was used to compare 4 (four) grid processing schemes. The percent error of the ecosystem area resulting from the hierarchy technique was in the range of 7.54-44.06%, while the dominance technique was 1.46-2.20%. In dominance technique, the difference between grid sizes of 10x10 meters and 25x25 meters was insignificant, as evidenced by the p- values of 0.479, 0.239, and 0.329 for mangrove, seagrass, and coral reef ecosystems respectively. The accuracy test obtained overall accuracy of above 85% for both 10x10 meter and 25x25 meter dominance techniques, so the results were considered good. Dominance was a more optimal processing MBSU technique, both using 10x10 meter and 25x25 meter grid sizes, but considering the processing time, the 25x25 meter grid was more efficient.
Keyword: Ocean Accounts, ecosystem extent, MBSU grid, coarse-graining

Judul: Mapping of Benthic Habitats Using Photogrammetric Methods in Yellu Waters, South Misool, Raja Ampat
Abstrak: Habitat bentik merupakan salah satu potensi sumberdaya perairan yang berperan sebagai tempat hidup dan berlindung berbagai jenis organisme. Untuk itu perlu dilakukan pemantauan dengan teknologi inderaja yang berkembang saat ini seperti penggunaan drone. Penggunaan drone memiliki keunggulan yaitu mampu terbang rendah sehingga menghasilkan citra foto udara dengan resolusi yang tinggi. Tujuan dari penelitian ini untuk memetakan dan menghitung luasan habitat bentik di Pulau Yellu menggunakan metode klasifikasi Object-Based Image Analysis (OBIA). Proses pengolahan data dilakukan dengan dua tahap yaitu segmentasi menggunakan algoritma Multiresolution Segmentation (MRS) dan klasifikasi menggunakan algoritma Support Vector Machine (SVM). Proses segmentasi melalui proses trial and error mendapatkan scale 300, 200, dan 100 pada level 1 dan scale 150, 100, dan 50 pada level 2. Dengan hasil klasifikasi memperoleh 6 kelas habitat bentik yaitu lamun, alga, rubble, pasir, karang hidup, dan karang mati. Tingkat akurasi yang didapatkan pada level 2 scale 150 sebesar 60%, pada scale 100 sebesar 82%, dan pada scale 50 sebesar 55%. Berdasarkan nilai akurasi, hasil klasifikasi yang paling sesuai dengan keadaan di lapang yaitu menggunakan scale 100 pada level 2., Benthic habitats are one of the potential water resources which have a role as a place to live and shelter for various organisms. For this reason, it is necessary to monitor using sensing technology that is currently developing, such as the use of drones. The use of drones has advantages as being able to fly low which produces aerial photo images with high resolution. This study was purposed to map and calculate the area of benthic habitat on Yellu Island using Object-Based Image Analysis (OBIA). The data processing was carried out in two stages which are segmentation using multiresolution segmentation (MRS) and classification using the support vector machine (SVM). The segmentation process was carried out through a trial and error process by getting a scale of 300, 200, and 100 at level 1 and a scale of 150, 100, and 50 at level 2. The classification results obtained 6 classes of benthic habitat seagrass, algae, rubble, sand, live coral, and dead coral. The accuracy level is 60% which was obtained at level 2 on a scale of 150, 82% on a scale of 100, and 55% on a scale of 50. Based on the accuracy value, the classification results that are most appropriate to the conditions in the field are using a scale of 100 at level 2.
Keyword: Fotogrametri, OBIA, Penginderaan Jauh, Perairan Dangkal, Mapping, Photogrammetry, Shallow Waters, SVM

Judul: Prenilasi Senyawa β-Diketon sebagai Prekursor 3-Prenilflavon
Abstrak: One group of flavonoids that has not been commonly synthesized is 3- prenylflavone. The main objective of this experiment was to synthesize precursor of 3-prenylflavone. Firstly, β-diketone was synthesized via 4 steps from phenol as starting compound with total yield of 24%. Prenylation of β-diketone with prenyl bromide and K2CO3 base produced 4 fractions which were separated by using preparative thin layer chromatography (PTLC) with n-hexane:EtOAc (8:2) as the eluent. Fraction with Rf = 0.80 was further separated by using preparative PTLC with n-hexane:EtOAc (99:1) as the eluent. Two fractions were obtained with Rf = 0.38 and 0.42. The first fraction has been characterized as diprenylated β-diketone with 49% yield. Application of protecting group on the phenolic OH group in β- diketone are needed to obtain monoprenylated β-diketone which can be further cyclized into 3-prenylflavone
Keyword: