Judul: Backscatter Characterization of Multi-temporal Radarsat Imagery in Ajkwa Tailing Deposition Area (Papua, Indonesia)
Abstrak: This Research investigated the characteristic of Multi-temporal Radarsat backscatter in F2N Identical Swath mode with more than 6 years of acquisition period. It included the assessment of the stability of Radarsat imageries for multi­temporal analysis by using variance analysis on the selected sample area of "permanent" landcover. This analysis, I was used to obtain Radarsat signal changes caused by the micro-geomorphology of tailing material propagation at the Modified Ajkwa Deposition Area (ModADA) of PT Freeport Indonesia, Timika, Papua. For this purpose, the 8 bit multi-temporal imageries was overlayed and interpreted, to describe the sequences of land cover dynamics resulting from the propagation of tailing material deposition. This overlay was visualy clear to describe the changes in signal characteristic due to certain condition of land surfaces. The result indicated different range of reflections. Diffuse reflection was detected on the undisturbed forest, natural comer reflection was related to the flooded vegetation, and specular reflection was mostly found on the established tailing. The reflection types was used to discriminate and to describe the segmentation class of Radarsat backscatter on the study area. Finally the segmentation analysis trial for each classs was implemented in the given image part. The intention was to assess the radar backscater characterstics as a potential information to study the sequence of moving tailing material in the tailing management purposes.
Keyword: Remote Sensing, Radar, Backscatter, Multi-Temporal, Segmentation, Tailing

Judul: Study on Backscatter Characteristic of ALOS PALSAR Imagery Within Tropical Rain Forest
Abstrak: This study examined the relationship between variables of forest stand and backscatter magnitude of ALOS PALSAR having pixel size of 6.25 x 6.25 meters and 50 x 50 meters. The main objective of this study is to identify the variable of stand that significantly affect the magnitude of backscatter in different spatial resolution. The study was carried out in dry land tropical forest located in Dairi Regency, North Sumatera Province, this study found that the variable of stands that influence the backscatter are (1) basal area of tree, biomass of tree and height of tree for resolution of 6.25 m, and (2) basal area of tree and biomass of tree for resolution 50 x 50 meters. These variables provides dominant influence on the backscatter magnitude. The study found that discriminating stand classes base on the above mentioned variables in quite prospective, providing accuracy more than 85% particularly in using a resolution of 50 x 50 meters, however less accuracy is provided by ALOS PALSAR imagery with higher spatial resolution.
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Judul: Peranan Hormon Dalam Mekanisme Kelahiran Pada Sapi
Abstrak: Kelahiran adalah proses keluarnya fetus dari kandungan atas pengaruh hormon, syaraf dan kontraksi otot uterus, diafragma dan otot perut. Proses kelahiran merupakan suatu rangkaian fisiologik yang kompleks yang dapat berlangsung beberapa hari, bahkan sampai seminggu. Meskipun studi mengenai mekanisme kelahiran telah banyak dilakukan, namun mekanisme yang tepat mengenai kelahiran belumlah diketahui secara pasti. Namun demikian kemungkinan besar faktor hormonal memegang peranan utama. Dalam proses kelahiran, uterus harus sudah bebas dari pengaruh progesteron dan berada dibawah pengaruh estrogen, oxytocin, relaxin dan prostaglandin. Oxytocin yang diha silkan oleh hypophysa posterior induk hewan, merupakan hormon yang memegang peranan penting dalam merangsang uterus untuk memulai berkontraksi. Pemberian estrogen, oxytocin dan prostaglandin dengan dosis tinggi dapat menyebabkan kelahiran sebelum waktunya.
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