Judul: Clustering Optimization using Particle Swarm Optimization for Medicinal Plant Identification System based on Digital Image
Abstrak: Indonesia is a country with a high level of biodiversity and there are 22,500 species of medicinal plants. The percentage of medicinal plant used by Indonesian people is only 4.4% or as much as 1,000 species. The people’s lack of knowledge becomes one of the cause of this low use of medicinal plant in Indonesia. People’s insight about medicinal plant can be increased by developing an identification system of medicinal plant. In this research, we used fuzzy local binary pattern (FLBP) to extract the feature. The number of digital image that used in this research are 1,440 leaf image. Unsupervised learning technique known as clustering is proposed to compare the results of the identification of medicinal plants with classification techniques. Clustering methods used is the k-means clustering and fuzzy c-means clustering. The disadvantages of both method is that the results are sensitive to the selection of initial cluster centers and the calculation of local solutions to achieve optimal conditions. This research applied a particle swarm optimization (PSO) method to overcome the weaknesses of k-means clustering and fuzzy c-means clustering. The application of PSO method in the identification system as a purpose to improve the identification of medicinal plants. This research builds four models of clustering is the k-means clustering, fuzzy c-means clustering, PSO based k-means clustering and PSO-based fuzzy c-means clustering. The development of clustering model using C++ programming language. Evaluation model of clustering using an accuracy value indicates that the PSO method can improve the identification of the k-means clustering and fuzzy c-means clustering. Accuracy of k-means clustering resulted 41.67% and PSO-based k-means clustering is 48%. Accuracy of fuzzy c-means clustering resulted in 50% and PSO based fuzzy c-means clustering is 52.33%. Evaluation of clustering models using computational time indicates the addition of time on the PSO method. The addition of algorithms led to growing number of data processing. Computation time on k-means clustering 291.3 seconds and PSO based k-means clustering 403.3 seconds. Computation time on fuzzy c-means clustering 59.65 seconds and PSO based fuzzy c-means clustering 60.1 seconds. PSO based fuzzy c-means clustering is a better method for generating high accuracy and faster computing time.
Keyword: Fuzzy C-Means Clustering, Fuzzy Local Binary Pattern, K-Means Clustering, Particle Swarm Optimization.

Judul: Identifikasi Tumbuhan Obat Berbasis Fraktal Menggunakan Clustering Fuzzy C-Means.
Abstrak: Identification medicinal plant species automatically still be a problem for recognizing various kind of medicinal plants in Indonesia. The research purpose is to develop medicinal plant identification system by using fractal and Fuzzy C-Means (FCM) clustering. Fractal method is used to extract image feture of the medicinal plant leaf. Beides, FCM clustering is needed to classify image feature medicinal plant into some lass or cluster. Two fractal approach used in this research are fractal dimension and fractal code. Fractal dimension is based on similiarity of the medicinal plant leaf image pattern and counted with box counting method, however fractal code is based on similiarity of the medicinal plant leaf image texture. This research used the data from the collection in Biofarmaka IPB plantation and glasshouse of Ex-Situ conservation of Indoensia Tropicana. 600 data is used contain of 20 variety of medicinal plants for each 30 sampel. This experimental result shows that 85.04% of FCM clustering based on dimension and 79.94% FCM clustering based on the fractal code. According to this result, medicinal plant identification system which are easy and with high accuracy will motivate public to empower and use medicinal plant in Indonesia which will increase Indonesian public health and wealth.
Keyword: 

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.
Keyword: