Judul: Machine Vision Design to Evaluate Performance of Purwoceng (Pimpinella pruatjan)  with Nutrition Dosage and Photo Periodicity
Abstrak: Tanaman purwoceng merupakan salah satu tanaman herba asli Indonesia yang berkhasiat obat dan dikategorikan hampir punah yang tumbuh di dataran tinggi. Budidaya tanaman purwoceng dilakukan pada ruang terkendali plant factory. Penelitian ini bertujuan membangun program computer untuk mengamati bentuk fisik tanaman purwoceng menggunakan dimensi fraktal, luas tajuk tanaman, dan luminosity untuk mengevaluasi keragaan tanaman purwoceng pada berbagai perlakuan dosis nutrisi dan lama penyinaran. Tahapan penelitian ini mengacu pada tahapan pembangunan program komputernya. Mengevaluasi keragaan tanaman purwoceng pada berbagai perlakuan dosis nutrisi dan lama penyinaran dengan menggunakan image processing. Terdapat 9 perlakuan untuk nutrisi dan lama penyinaran. Program luas daun mengacu pada nilai jumlah piksel yang memiliki presentase MAPE sebesar 5,67%. Pada 9 perlakuan nutrisi dan pencahayaan, perlakuan 1000 ppm-14 jam memiliki nilai rata-rata dimensi fraktal terbesar dan perlakuan 1000 ppm-16 jam memiliki luas tajuk daun terbesar, dan nilai luminosity terkecil ada pada perlakuan 1500 ppm-16 jam. Melalui nilai luas daun, luminosity, dan dimensi fraktal sistem ini mampu memberikan informasi perlakuan terbaik untuk pertumbuhan tanaman purwoceng., Purwoceng is one of Indonesia's native herbaceous plants that has medicinal efficacy and categorized as almost extinct that grows in the plateau. Cultivation of purwoceng is carried out in the Plant Factory. This research aims to build a computer program to observe the physical form of purwoceng using fractal dimensions, leaf area, and luminosity to performance of purwoceng with nutrition dosage and photo periodicity. The stages of the research refers to computer development program. Evaluate the performance of purwoceng on nutrition dosage and photo periodicity using image processing. There are 9 treatments for nutrition and photo periodicity. The leaf area program refers to the value of the total pixels that have Mean Absolut Percentage error of 5.67%. In 9 nutrient and lighting treatments, the 1000 ppm-14 hours treatment has the largest fractal dimension value and the 1000 ppm-16 hours treatment has the largest leaf area, and the smallest luminosity value is in the 1500 ppm-16 hours treatment. This system is able to provide the best treatment information for the growth of purwoceng through the leaf area, luminosity, and fractal dimensions.
Keyword: fractal dimension, image processing, leaf area, luminosity, purwoceng

Judul: Design of Purwoceng Plant Growth Monitoring Systems in Mini Plant Factory Based on Machine Vision
Abstrak: Purwoceng adalah tanaman obat yang dikategorikan hampir punah karena langkanya budi daya dan lahan yang sesuai untuk budi daya purwoceng. Upaya pelestarian dan peningkatan tanaman purwoceng dilakukan dengan budi daya di mini plant factory yang menerapkan monitoring pertumbuhan tanaman berbasis machine vision agar pertumbuhan tanaman dapat terpantau dengan baik. Tujuan penelitian ini adalah merancang sebuah sistem pemantauan pertumbuhan tanaman yang mampu memantau perkembangan keragaan tanaman purwoceng dilihat dari parameter total luas daun dan kadar kehijauan daun di mini plant factory berbasis machine vision. Tahapan penelitian ini mengacu pada metode System Development Life Cycle (SDLC) yang terdiri dari investigasi sistem, analisis sistem, desain sistem, implementasi sistem dan pengujian sistem. Program total luas daun pada sistem ini memiliki tingkat error sebesar 42,69% dan setelah dikalibrasi menjadi sebesar 6,82%. Program kadar kehijauan daun diperoleh dari nilai rataan green pada citra daun untuk mengetahui kepekatan kadar warna hijau pada daun. Berdasarkan pemantauan tanaman purwoceng pada 100-112 HSPT melalui data total luas daun dan kadar kehijauan daun, sistem ini terbukti mampu memberikan informasi pertumbuhan tanaman yang tidak normal secara akurat., Purwoceng is a medicinal plant that is categorized as endangered due to the scarcity of cultivation and suitable land for purwoceng. Efforts to preserve and improve purwoceng plants carried out by cultivate them in mini plant factory that implements machine vision-based plant growth monitoring so that purwoceng growth can be monitored properly. The purpose of this research is to design a plant growth monitoring system that can monitor the purwoceng appearance in the from of total leaf area and leaf greenness based on machine vision in mini plant factory. The stages of this research refer to the System Development Life Cycle (SDLC) method that consists of system investigation, system analysis, system design, system implementation and system testing. Total leaf area program in this system has an error rate of 42.69% and after being calibrated it becomes 6.82%. The leaf greenness program is obtained from the average value of green in the leaf image to determine the concentration of green color in the leaves. Based on the monitoring of purwoceng plants at 100-112 HSPT through data on total leaf area and leaf greenness, this system was proven to be able to provide accurate information on abnormal plant growth.
Keyword: leaf greenness, machine vision, monitoring system, purwoceng,, total leaf area

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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