Judul: Pengaruh Perubahan Tutupan Lahan Mangrove terhadap Kerentanan Pesisir Kabupaten Karawang.
Abstrak: Keberadaan mangrove sebagai pelindung alami wilayah pesisir dari kerusakan yang disebabkan oleh arus, gelombang dan efek negatif dari kenaikan muka laut terancam akibat kegiatan manusia seperti konversi ekosistem mangrove menjadi lahan budidaya termasuk tambak. Penelitian ini menduga laju perubahan tutupan lahan mangrove di Kabupaten Karawang pada tahun 2000-2020 serta menganalisis coastal vulnerability index (CVI) tahun 2000 dan 2020 setelah tutupan lahan mangrove berubah. Analisis perubahan tutupan lahan mangrove menggunakan klasifikasi terbimbing, membagi wilayah pesisir menjadi kelas mangrove, badan air, lahan terbangun, vegetasi dan lahan terbuka. Kerentanan pesisir menggunakan CVI dengan menganalisis parameter berupa geomorfologi pantai, perubahan garis pantai, kemiringan pantai, kenaikan muka laut, tinggi gelombang laut rata-rata dan kisaran pasang surut. Tutupan lahan mangrove di Kabupaten Karawang mengalami peningkatan dari dari 77,69 ha pada tahun 2000 menjadi 353,12 ha pada tahun 2020 dengan rata-rata laju perubahan tutupan lahan mangrove sebesar 13,77 ha/tahun. Perubahan ini menyebabkan 61% wilayah pesisir mengalami penurunan kelas kerentanan pesisir, 9% mengalami kenaikan kelas kerentan dan 30% tidak mengalami perubahan. Sebanyak 50% wilayah pesisir yang dianalisis mengalami perubahan tutupan lahan mangrove.
Keyword: beach, coastal vulnerability index, grid, mangrove, supervised classification

Judul: Study of Mangrove Land Cover Changes and Sea Level Rise on Coastal Vulnerability of Bekasi Regency
Abstrak: Perubahan tataguna lahan, khususnya tutupan mangrove sangat mempengaruhi kerentanan kawasan pesisir. Kecamatan Muara Gembong, Kabupaten Bekasi ditetapkan sebagai salah satu kawasan hutan lindung mangrove. Konversi lahan mangrove serta bencana erosi pantai mengancam kerentanan kawasan pesisir Kabupaten Bekasi. Penelitian ini mengkaji perubahan tutupan lahan mangrove serta menganalisis kerentanan pesisir wilayah Kabupaten Bekasi tahun 2000 dan 2020. Pengkajian perubahan tutupan lahan mangrove dilakukan dengan menggunakan supervised classification untuk membaginya menjadi 5 kelas tutupan lahan, yaitu mangrove, vegetasi, lahan terbangun, lahan terbuka, dan badan air, kemudian memvalidasinya menggunakan Normalized Difference Vegetation Index (NDVI). Metode coastal vulnerability index (CVI) digunakan untuk menilai kerentanan pesisir Kabupaten Bekasi. Klasifikasi kerentanan yang dilakukan di wilayah kajian yang dibagi menjadi 72 grid menunjukkan bahwa separuh diantaranya (36 grid) tergolong memiliki kerentanan tinggi. Penurunan tutupan mangrove dari tahun 2000 sampai 2020 sebesar 23,55% menyebabkan kerentanan Muara Gembong bertambah luas, yang ditunjukkan oleh tambahan 26 grid yang memiliki kerentanan tinggi. Melindungi mangrove yang ada dan merestorasi garis pantai yang terdegradasi pelu diprioritaskan untuk mengurangi risiko bencana di Kawasan pesisir Kabupaten Bekasi., Coastal areas are particularly vulnerable to the impacts of human induced climate change and land-use change, especially mangrove cover. Muara Gembong District, Bekasi Regency is designated as one of the mangrove protected forest. However, rampant conversion has been causing coastal erosion in Bekasi Regency. This study examines changes in mangrove land cover and analyzes the coastal vulnerability of the Bekasi Regency area in 2000 and 2020. The assessment of mangrove land cover change was carried out using supervised classification five classes of land cover, including mangroves, vegetation, built-up area, open land, and water bodies, then validate it using the Normalized Difference Vegetation Index (NDVI). The coastal vulnerability index (CVI) method was adopted to assessthe coastal vulnerability of Bekasi Regency. The vulnerability classification carriedout in the study area divided into 72 grids showed that half of them (36 grids) were classified as highly vulnerable. The decrease mangrove cover during 2000-2020 of 23.55% caused the vulnerability of Muara Gembong to increase, as shown by additional 26 grids that are highly vulnerability. Protecting the existing mangroves and restoring the degraded area should be prioritized to reduce risks of disaster in the coastal zone of Bekasi Regency
Keyword: climate change, CVI, land-use, Muara Gembong, shoreline

Judul: Separation of Neodymium from U3Si2/Al Fuel Plate for Burn-Up Determination
Abstrak: Neodymium is a common fission product produced in nuclear fission reactions. Neodymium in this study was chosen as a burn-up indicator for U3Si2/Al fuel element plates because the neodymium isotope is a stable fission product with a fairly high yield. Some procedures were carried out to separate neodymium, starting with the separation of cesium isotopes (137Cs, 134Cs) through the precipitation method, then separation of uranium isotopes (235U, 238U) and plutonium isotopes (239Pu, 238Pu) with Dowex 1x8 ion exchange resin, and separation of neodymium (Nd), samarium (Sm), as well as cerium (Ce) with Dowex 1x4 ion exchange resin. The Cs recovery reached 99.95%. The U and Pu isotopes resulting from the separation are subjected to an electrodeposition process and the weight of each isotope can be measured with an alpha spectrometer. The separation results of Nd from Sm and Ce have been proven using an XRF spectrometer. The neodymium isotopes separation was corrected using the standard addition method, and an average total Nd content of 2.4 ppm was obtained in the PEB U3Si2/Al bottom solution. It is hoped that this separation method can be applied in determining burn-up of nuclear fuel.
Keyword: neodymium, burn-up indicator, U3Si2/Al fuel plate