Judul: Pembangkitan dan penyelesaian sliher link dengan answer set programming dan procedural programming
Abstrak: Slither Link is a popular pencil-based puzzle game similar to Sudoku. This problem has been shown to be NP-Complete. The goal of the game is to link grid segments forming a loop such that the number of lines adjacent to a cell is equal to the number written on the cell. In this research, we investigate the use of Answer Set Programming as a formal representation of the game, and to prove an alternative solving method, as opposed to the procedural method. We then perform experiment to test the efficiency of Answer Set Programming compared to the procedural method in solving Slither Link. For the Anser Set Programming method, we use DLV as the solver, whereas for the procedural method we write a program in C++ to solve Slither Link in a procedural manner. The result shows that ASP performed consistently better than the procedural method we use.
Keyword: 

Judul: Perbandingan Answer Set Programming dan Iterative Deepening Search dalam Menyelesaikan Game N-puzzle
Abstrak: N-puzzle is one of the known NP-complete problems in the field of puzzles and games. The purpose of N-puzzle is to arrange numbers from 1 to (n2-1) in an n x n grid, with one grid contains a blank square. The research aims to compare the use of Answer Set Programming (ASP), as one of the currently used formalism to express and solve hard computational problems, with the traditional Iterative Deepening Search (IDS) in solving the N-puzzle. An encoding of N-puzzle problem and solver was devised and executed using the DLV system, while IDS is implemented as an ad-hoc program solving the N-puzzle problem. The result of experiment shows that the ASP using DLV is more effective in finding solutions, because it requires no depth parameters to find solutions, while IDS does. On the other hand, the IDS implementation was more efficient in terms of execution time.
Keyword: 

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: