Judul: Sistem pakar Fuzzy untuk diagnosis penyakit pada tanaman cabai merah
Abstrak: Chili plant is one plant that has high economic value for farmers in Indonesia. The risk of plants that have high economic value was also high. Production of the national average chili plants is still not maximized. One reason is the number of pests and pathogens that can attack chili plants and cause plants can not grow optimally. This study developed an expert system that uses the concept of Fuzzy Inference System with Mamdani method to diagnose disease in chili plants. This system can provide early diagnosis of diseases affecting the chili plant from the symptoms caused without having to ask directly to the specialist or expert. The parameters used as input parameters consist of fuzzy and non-fuzzy parameters. Fuzzy parameters such as leaf color, the color or pattern of leaf spot, leaf spot diameter, number of leaf spot, stem color, pH, and moisture. The non-fuzzy parameters used are the location of plant, leaf condition, position of leaf spot, stem rottenness, spots on the stems, bumps on the stem, blackish brown ring at the base of the stem, and dead shoots. The results showed that the Fuzzy Inference System can be used as a way to cope uncertainty for the case of chili plant disease diagnosis.
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Judul: Sistem Pakar (Expert System) Diagnosa Penyakit Tanaman Cabai Besar Merah (Capsicum'annuum L.) Berbasis Internet Dan Multimedia
Abstrak: Cabai besar (Capsicum annuum 1.) merupakan salah satu komoditas hortikultura dengan nilai ekonomis tinggi. Menurut Pennadi dan Kusandriani (1994), rendahnya produksi cabai besar di Indonesia disebabkan oleh beberapa faktor, diantaranya adalah teknik budidaya yang belum optimal, minimnya benih bermutu, tingginya serangan hama penyakit serta faktor lingkungan yang kurang menguntungkan. Faktor yang paling berpengaruh terhadap penurunan hasil panen cabai merah adalah adanya serangan hama dan penyakit pada tanaman. Menurut Koestoni (1992), serangan hama-hama pengisap Thrips parvisipinus, Myzus persicae dan Polyphagotarsonemus latus dapat menurunkan hasil panen sebanyak 40-80%, ulat Spodoptera litura dapat menyerang buah cabai dengan kerusakan sekitar ± 10%. Serangan lalat buah Bactrocera dorsalis dapat menimbulkan kerugian sekitar 12-17% (Vos, 1994). Tingginya nilai kerugian yang diakibatkan oleh serangan hama penyakit dipengaruhi oleh rendalmya informasi dan pengetahuan petani tentang hama penyakit dan ketidaktepatan dalam pengendalian hama penyakit. Selain itu, tenaga ahli yang diharapkan dapat membantu petani mengatasi masalah penyakit tanaman tidak tersedia setiap saat.
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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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