Judul: Thermal Characteristics and Dynamics of Tropical Cyclone over Western North Pacific Ocean: A Case Study of Typhoon Songda (Chedeng) 2011
Abstrak: The frequent occasion of Tropical Cyclone (TC) over Western North Pacific (WNP) Ocean lies from 10˚N to 26˚N and 121˚E to 170˚E. Sources of TC development come from warm ocean temperature where latent heat is released during condensation processes and subsequently concentrated in the boundary layer. Relative humidity at 850-700 hPa is responsible to produce the most intense storm. Meanwhile, weak vertical wind shear between 850-200 hPa is one of the dynamical factors that lead to the development of TC. Pressure level of 850-200 hPa is chosen to minimize the thermodynamic effect in the lower troposphere. Typhoon Songda (Chedeng in the Philippines) or TSC lasted from May 18th to 30th, 2011 and strengthened into powerful Super Typhoon stage between May 24th and 27th. Long curving track and the exhibition of all sequences of TC life cycle, TSC is then considered as an ideal case of TC. The objective of the study with case of TSC is to investigate the role of thermal characteristics and dynamics on TC intensity. The research is carried out by using Advanced Research of Weather Research and Forecasting model (WRF ARW model) version 3.3. Two domains are employed in the model. The first domain situate from 02˚N to 40˚N and 118˚E to 149˚E and cover spatial resolution () of 33.1 km. The second domain situate from 09˚N to 27˚N and 119˚E to 132˚E with of 11 km. Timestep of the model () is 120 seconds. The model is supported by the following physical parameterization, i.e., Yonsei University Scheme (YSU) in the boundary layer, Kain-Fritsch scheme (KF) in the cumulus, and WRF Single-Moment 3-class scheme in the microphysics. Initial meteorological condition prior to the formation of the cyclone is generated using WRF ARW standard-release model. Sensitivity of the model output is obtained from a selected single-parameter change scenarios, namely, 10 % to 20 % decrease and increase of wind shear initial data at 850-200 hPa, and by 10 % to 20 % decrease of relative humidity initial data at 850-700 hPa. The result showed that the negative correlations between wind shear and intensity are found in wind shear scenarios. Wind shears of 10 ms-1 which lead to strengthening of the wind intensity in the early period of Typhoon development are found in wind shear scenarios. The effect of wind shear changes on wind intensity is statistically significant in the 20 % wind shear scenarios. During mature stage, weak wind intensity occurred when wind shear increase as given in the WRF standard-release and the 20 % decreasing scenario. Different situation is found in the 20 % increasing scenario where wind shear tend to weak and lead to strong wind intensity at this stage. Meanwhile, the reduction of moisture supply at 850-700 hPa resulting from 20 % decreasing relative humidity play a major role in the weakening of wind intensity and reduces mechanical energy of the cycle process as much as 300 J kg-1.
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Judul: Pengaruh Siklon Tropis terhadap Karakteristik Gelombang Permukaan di Laut Timor.
Abstrak: Tropical cyclones (TC) occuring in the Southern Hemisphere may affect Indonesian waters, particularly in the Timor Sea, through extreme wave. Study objective was to characterize TC occurring in the Timor Sea, and its effects to surface waves. Area study was located between 110º-137º E and 7º-15º S. Reanalysis data (interaction ocean-atmospheric) were originated from the USECMWF and NOAA, observation data (TC trajectory) were originated from Bureau of Meteorology from Australia and the Philippines between 2001-2010. Data were analyzed using statistical methods, the Saffir-Simpson scale, time series plots, Hovmoller diagrams and continuous wavelet transform. TC phenomena in the Timor Sea were generally took place during the Northwest Monsoon until the first transition season (December to April). March was the peak period for TC in the Timor Sea with Saffir-Simpson category 1. Mean period of TC life cycle was 4 days, with the longest cycle lasted for 11 days and the shortest was 2 days. TC trajectory in general was started from ~7° S (northern Australia), recurved near Timor Sea and terminated at ~15° S (mainland Australia or the Indian Ocean). Mean surface wave height in the Timor Sea during TC was 3.2 m.
Keyword: data analysis, Timor Sea, tropical cyclone, extreme wave, oceanatmosphere interaction

Judul: Produksi Gelatin Halal Dari Kulit Kaki Ayam Dengan Penghilangan Lemak Berbeda Dan Aplikasinya Pada Es Krim
Abstrak: Gelatin merupakan hasil dari hidrolisis parsial protein kolagen. Industri pangan dan non pangan banyak menggunakan gelatin. Kegunaan gelatin khususnya dalam industri pangan adalah sebagai pembentuk busa, penstabil, pembentuk gel, perekat, pengental dan pengemulsi. Penelitian ini bertujuan untuk menentukan prosedur pembuatan gelatin kulit kaki ayam yang halal dan menghasilkan mutu gelatin yang baik serta mengevaluasi aplikasi gelatin yang dihasilkan pada produk es krim. Penelitian ini terdiri atas 2 tahap, yaitu: pembuatan gelatin kulit kaki ayam dengan metode penghilangan lemak yang berbeda, dan aplikasi gelatin pada es krim. Setiap perlakuan dilakukan ulangan sebanyak 3 kali. Rancangan yang digunakan dalam penelitian ini adalah rancangan acak kelompok (RAK). Data kualitas fisikokimia, warna dan kualitas es krim dianalisis menggunakan ANOVA dan dilanjutkan dengan uji perbandingan berganda Duncan. Data sifat sensori es krim diuji secara non parametrik (Kruskal-Wallis). Hasil penelitian menunjukkan bahwa metode penghilangan lemak yang berbeda berpengaruh secara signifikan (P<0.05) terhadap kadar protein, kadar lemak, viskositas dan intensitas warna kuning gelatin. Metode kulit tanpa direndam dengan NaOH 0.05 M dan larutan gelatin yang disentrifuse pada 3500 rpm selama 15 menit menghasilkan viskositas (P<0.05) tertinggi dan kandungan lemak terendah (P<0.05). Kualitas es krim dengan penambahan gelatin kulit kaki ayam tidak berbeda dengan penambahan gelatin komersial. Uji sensori hedonik es krim menghasilkan penilaian suka sampai sangat suka pada es krim yang ditambahan gelatin kulit kaki ayam. Kesimpulan dari penelitian ini adalah metode penghilangan lemak yang terbaik untuk menghasilkan gelatin dari kulit kaki ayam adalah metode hidrolisis tanpa perendaman kulit dalam NaOH dan melakukan pemurnian larutan gelatin dengan menggunakan sentrifugasi. Karakteristik mutu gelatin kulit kaki ayam yang dihasilkan telah memenuhi standar gelatin halal dengan kualitas yang baik. Aplikasi gelatin kulit kaki ayam dalam pembuatan es krim menghasilkan mutu es krim yang baik dan mutu sensori yang diterima oleh panelis.
Keyword: es krim, gelatin, halal, kualitas, kulit kaki ayam