Judul: RDF Retrieval untuk Dokumen Bahasa Indonesia dengan Pembobotan Per Konteks
Abstrak: Penelitian temu kembali informasi pada dokumen RDF sudah dilakukan. Akan tetapi, penelitian tersebut belum memperhatikan struktur dari dokumen RDF. Penelitian ini mengembangkan sistem temu kembali informasi pada dokumen RDF dengan memperhatikan struktur dokumen yaitu dengan membedakan bobot pada setiap konteks (tag) yang ada pada dokumen RDF. Pembobotan yang digunakan adalah tf-idf. Bobot yang dihasilkan pada setiap konteks dikalikan dengan suatu koefisien dengan nilai 0.2, 0.4, 0.6, 0.8, atau 1.0. Sistem temu kembali informasi yang dibangun dievaluasi dengan menggunakan 29 kueri. Penelitian ini menghasilkan nilai average precision (AVP) sebesar 0.89721. Nilai tersebut lebih tinggi 1.91% jika dibandingkan dengan sistem temu kembali informasi yang tidak membedakan bobot per konteks.
Keyword: Information retrieval, RDF, Pembobotan konteks, Dokumen RDF, Penyimpanan dokumen pada sesame, Proses indexing, Pencarian dokumen, Informasi dokumen

Judul: Metode Pembobotan Kata Berbasis Sebaran untuk Temu Kembali Informasi Dokumen Bahasa Indonesia
Abstrak: Term weight algorithm plays an important role in the process of document searching, which is greatly influenced by the precision and recall results of the Search Engine. Currently, TF-IDF term weight algorithm is widely applied in language models to build the search engine systems. Since term frequency is not the only discriminator which is necessary to be considered in term weighting and make each weight suitable to indicate the term’s importance, term weighting algorithm based on term distribution has been developed. In a single document, a term with higher frequency and closer to hypo-dispersion distribution usually contains more semantic information and should be given higher weight. One the other hand, in collection of documents, the term with higher frequency and hypo-dispersion distribution usually contains less information. This research implements term weight based on term distribution, with Local Term Weight Algorithm and Global Term Weight Algorithm for the documents in Indonesian Language. The result of this research is a Search Engine with an average precision of 84.8%.
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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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