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: Relations of character Morphology and Anatomy of Patchouli Plant (Pogostemon spp.) with Plant Production per Clumb and Oil Cells Density to Get Best Variety.
Abstrak: Indonesia merupakan negara pengekspor minyak atsiri dengan kualitas terbaik di dunia, terutama minyak atsiri yang berasal dari tanaman nilam (Pogostemon spp.) yang kaya akan kandungan patchouli oil. Untuk mendapatkan varietas tanaman nilam yang unggul diperlukan analisis untuk melihat pengaruh langsung dan tidak langsung sifat-sifat kuantitatif tanaman nilam terhadap produksi tanaman per rumpun dan kerapatan sel minyak, sehingga seleksi terhadap varietas unggul akan lebih efisien. Parameter yang diamati yaitu: produksi per rumpun, kerapatan sel minyak, tinggi tanaman, diameter batang, panjang daun, lebar daun, jumlah daun per rumpun, jumlah cabang per tanaman, jumlah ranting per tanaman, bobot daun per helai, kerapatan trikoma, kerapatan stomata, dan luas daun. Hasilnya menunjukkan bahwa parameter yang berpengaruh langsung dan menunjukkan hubungan yang sebenarnya terhadap produksi tanaman per rumpun ialah kerapatan sel minyak, tinggi tanaman, diameter batang, jumlah daun per rumpun, jumlah cabang per tanaman, bobot daun per helai, dan luas daun. Panjang dan lebar daun memberikan pengaruh tidak langsung terhadap jumlah produksi. Parameter yang berpengaruh langsung dan menunjukkan hubungan sebenarnya terhadap kerapatan sel minyak ialah, produksi tanaman per rumpun, lebar daun, jumlah daun per rumpun, dan kerapatan trikoma. Panjang daun dan kerapatan stomata memberikan pengaruh tidak langsung terhadap kerapatan sel minyak.
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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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