Judul: Pemanfaatan Sistem Pakar untuk Menentukan Varietas Unggul Tanaman Nilam
Abstrak: Patchouli is a producer of essential oils that has a higher export value. The selection of good and excellent patchouli plant seed is necessary in order to produce good quality of essential oils. This research assesses superiority of patchouli plant seeds using three known superior varieties as a reference. The varieties are tapak tuan, lhokseumawe, and sidikalang variety which are derived from the aceh varieties. To this purpose, we develop an expert system which is aimed to assist nilam developers in selecting good seeds and patchouli superior plants. During the process, morphological characteristics of patchouli plant varieties result in about 108 rules. Further examination determined only 27 rules are applicable to determine its superiority while the remaining rules are inapplicable. The expert system was assessed using 30 patchouli plant seeds to verify system correctness. Note that 30 plant seeds being assessed was known as superior variety prior to its assessment. Assessment results recognized that 93% of the plant seed is categorized as superior type. Additional assessment using 50 unknown patchouli variety was also carried out. The results of the assessment by the expert system concluded that 84% of the patchouli plants were determined as superior patchouli plants, and results from the expert assessment concluded that 86% are superior patchouli plants. In conclusion, the expert system developed is able to determine patchouli plant seed superiority based on its morphology with relatively good accuracy.
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Judul: Sistem Pakar Kesesuaian Lahan untuk Tanaman Nilam (SPKLTN)
Abstrak: The land is a mixture of physical and natural environment that includes its climate, ground, relief, and hydrology. The mixture of soil has consequences of its land use. On the other hand, the success of agriculture and agro-industry is influenced by the success of its agriculture cultivation. This research intends to build an expert system that can be used to determine evaluation of crop land, in particular, for patchouli crop. The Expert System of Patchouli Land Suitability is aimed to provide information on land characteristics that are suitable for patchouli . We make use of the expertise of Dr. Ir. Rosihan Rosman, M.Sc to provide knowledge to the expert system developed. The processing input for the expert system comes in two formats, i.e., fuzzy inputs and non-fuzzy inputs. Fuzzy Inference System (FIS) with Mamdani method was first used as the inference method for the fuzzy output followed by an application of non-fuzzy inputs. The expert system provides three categories of evaluation, i.e., very suitable, suitable, and unsuitable land cultivation for patchouli. Each category has specific land characteristics tied with the evaluation. Furthermore, the expert system was assessed on sixteen different lands to verify system accuracy. Assessment results present 75% accuracy when verified using human expert assessment.
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Judul: Hamiltonian formulation for linear waves motion in two layers fluid
Abstrak: The surface wave could be considered as a wave that separates two fluids, namely water and air. Based on this assumption, it is introduced the interfacial wave, a wave between two layers of fluid with different density. The formulation of interfacial waves motion begins with deriving the base equation of irrotational ideal fluid. Furthermore, according to irrotational fluid assumption, the base equation can be stated in velocity potential. In this derivation, the fluids domain is assumed to be restricted by rigid lid boundary conditions, both at the upper and lower limit. Therefore, the interfacial waves motion can be explained in a hamiltonian formulation. In the hamiltonian formulation, total energy is defined as the sum of kinetic and potential energy. The hamiltonian system is obtained from reduction of kinetic energy by using the Dirichlet Neumann Operator. The resulted kinetic energy equation is nonlinear. Therefore, this form is linearized by first part of the Taylor expansion. This linearization gives a dispersion relation of linear wave. Based on this dispersion relation, the phase speed of the linear wave depends on the density ratio of the two layers fluid.
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