Judul: Waveform Retracking Satelit Jason 2 Tahun 2012 Di Pesisir Pulau Mentawai, Sumatera Barat
Abstrak: Waveform retracking used for the satellite Jason 2 is a retracking method for analyzing waveform pulse shapes that were repeatedly transmitted from sea surface and received by Altimetry Satellite sensor. Waveform shape affected by the noise when it approaches the shore and this forms are difficult to analyze, but such effect is dissapeared when the wave formed on the open seas. The location for this research is the coastal areas Mentawai, West Sumatra with the Jason 2 satellite during 2012 using Sensor Geophysical Data Recordtype D (SGDR-D) data and Earth Gravitational Model 2008 global geoid (EGM08) data. The purpose of this research was to compare the result of the waveform retracking to the ocean retracking method in coastal areas, analyze Improvement Precentage (IMP) values of Sea Surface Height (SSH) changes, and SSH during 2012 period. This research uses tracks with the number 001 on periods of 130, 135, 148, 151, 162, and 164 with distance category 0 – 10 km, 10 – 50 km, and 50 – 100 km. The waveform analysis are Offset Centre of Gravity (OCOG), ocean, ice, threshold (level 10%, 20%, 50%), and improve retracking (level 10%, 20%, 50%). Waveform shape in the Mentawai coast, West Sumatra were peak echoes. Waveform shape that formed on the open seas has the ideal shape, which is brown + peaky echoes. Performance in each waveform retracking methods are different in each distance. Threshold 10% method is the most optimal method for analyzing waveform contained in every track. Sea surface height average from geoid in track 001 during 2012 period in West Monsoon (November-April) is the 5,03 m, whereas East Monsoon (May-October) is the 4,91 m and the most optimal method is the threshold 10%.
Keyword: SSH, IMP, Jason 2, retracking, waveform

Judul: Waveform Retracking Satelit Jason-2 pada Pesisir Selatan Jawa Tengah dan Jawa Barat
Abstrak: Satellite altimetry Jason-2 has been used to observe global ocean surface topography with accuracy approximately up to 2.5 cm on the offshore. However, the accuracy will be significantly reduced over coastal waters due to the signal received by satellite was interfered by reflected signal from the land. Distruption to the received signal by the satellite will affect the waveform shape becomes more complex and more difficult to be analyzed. The waveform formed on the offshore, is the ideal waveform shape so called ocean waveform or Brown waveform. Calculation of the range between the satellite and earth's surfaces using ocean retracking method is not accurate if the analyzed waveform shape is not ideal. Therefore, it is necessary to do retracking using other methods. The purpose of this research was to compare the ability of several retracking methods and ocean retracking methods to produce better value of sea surface height (SSH) on coastal waters. This study used data from the SGDR-D (Sensor Geophysical Data Record type D) satellite Jason-2 (pass 242, 051, and 064 during the period of 2010 - 2012 at southern coastal of Central Java and West Java) and global geoid data EGM08 (Earth Gravitational Model 2008). In this research, compared the analysis perfomances of several retracking methods, such as the OCOG (Offset Centre of Gravity), ice, threshold, and improved threshold and the result from analysis of ocean retracking method. Analytical performances of the used methods were measured by calculating the improvement percentage (IMP) results. Results of this research indicated waveforms from coastal waters has a complex and peaky shape, in contrast to the condition of the waveforms on the offshore with the ideal shape. In general, ice retracking method was the most optimal method for analyzing waveforms on each pass. That method was able to produce sea surface height value from offshore to coastal waters with high accuracy. The trend of sea level change that occurred during 2010 - 2012 at the observation point in each pass used optimal retracking method indicated a declining pattern. Sea level change at the observation point on the pass 242, 051, and 064 were -18.17, -47.23, and -39.97 mm/year inrespectively.
Keyword: 

Judul: Infeksi Clostridium perfringens pada unggas dan cara - cara penanggulangannya
Abstrak: Clostridium perfringens atau disebut juga C. welchii adalah salah satu mikroba yang dapat menyerang unggas terutama ayam broiler dan kalkun yang dipelihara secara intensif dengan sistem litter. Kejadiannya bersifat sporadis dan merupakan masalah yang cukup besar, karena angka kematian unggas dapat mencapai 60 %. Clostridium perfringens adalah bakteri berbentuk batang dengan ukuran 0.9-1.3 x 3.0-9.0 mikrometer, tunggal atau berpasang-pasangan dan jarang membentuk rantai. Kuman yang bersifat Gram labil ini dapat membentuk spora yang terletak sentral atau sub terminal. Kuman ini tumbuh baik pada media agar darah, dalam suasana anaerob. Daya tahannya terhadap pemanasan ialah 2 jam pada suhu 100..°C atau akan rusak pada pemanasan dengan suhu 120 °C selama 20 menit. (Bergey, 1975). Secara normal C. perfringens terdapat dalam saluram pencernaan manusia maupun hewan, termasuk unggas. Pada saluran pencernaan unggas kuman ini terdapat dalam caecum dan usus besar, tetapi jarang pada usus kecil. ...
Keyword: