Judul: Implementasi Hybrid Parallelization pada Algoritme Global Pairwise Alignment.
Abstrak: Algoritme pairwise alignment (PA) merupakan salah satu metode yang umum digunakan dalam penjajaran sekuens. PA terbagi menjadi 2 jenis yaitu global pairwise alignment (GPA) dan local pairwise alignment. Perkembangan teknologi yang semakin pesat menyebabkan ukuran data sekuens bertambah besar sehingga pemrosesan data tersebut akan memakan waktu yang sangat lama apabila hanya dikerjakan dalam satu prosesor. Oleh karena itu, suatu metode pemrosesan paralel dibutuhkan untuk mempersingkat waktu komputasi. Penelitian ini bertujuan mempercepat algoritme GPA menggunakan skema partisi data blocked columnwise dengan menggunakan metode hybrid parallelization. Hybrid parallelization dilakukan dengan menggabungkan metode sistem memori terdistribusi dengan sistem memori bersama. Hasil penelitian menunjukkan nilai speedup pada percobaan menggunakan 2, 3, dan 4 komputer masing-masing adalah 5.3, 6.9, dan 7.77 pada ukuran data 16000 pasang basa dan nilai efisiensi berturut-turut adalah 66%, 58%, dan 49%. Kinerja terbaik dicapai menggunakan 4 komputer, sedangkan skalabilitas memori terbaik diperoleh menggunakan 2 komputer.
Keyword: hybrid parallelization, memori bersama, memori terdistribusi, pairwise alignment, pemrosesan paralel

Judul: Akselerasi Global Pairwise Alignment Dengan Skema Partisi Blocked Column-Wise Pada Sistem Memori Terdistribusi
Abstrak: Algoritme global pairwise alignment (GPA) yang digunakan untuk menyejajarkan sepasang sekuens DNA perlu diparalelisasi untuk mempersingkat waktu eksekusi. Skema partisi berpengaruh terhadap kinerja algoritme GPA paralel mengingat algoritme ini mengadopsi metode pemrograman dinamis. Penelitian ini mempercepat algoritme GPA menggunakan skema partisi blocked column-wise pada sistem memori terdistribusi. Pararelisasi algoritme GPA dilakukan dengan model pemrograman message-passing menggunakan standar message passing interface (MPI). Parameter panjang sekuens yang digunakan bervariasi dari 1000 bp sampai paling panjang 30 000 bp. Hasil yang diperoleh menunjukkan speedup menggunakan 2, 3, dan 4 buah PC berturut-turut adalah 1.79, 2.58, dan 3.37 untuk panjang sekuens 30 000 bp. Sedangkan efisiensi menggunakan jumlah PC dan panjang sekuens yang sama berturut-turut mencapai 89.32%, 85.97%, dan 84.19%. Algoritme GPA paralel yang dikembangkan menunjukkan skalabilitas.
Keyword: message-passing, memori terdistribusi, pairwise alignment, skema partisi

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.
Keyword: