Judul: Optimasi jaringan syaraf tiruan menggunakan algoritme genetika
Abstrak: Neural network is one of common computational model to recognize pattern. Backpropagation algorithm can be used as method to train the networks weights. One of the drawbacks of backpropagation training is the initial weights generated randomly. It causes the instability of neural network training performance. Because of this, many experiment and training must be conducted to obtain the desired model. This research combine genetic algorithm and neural network to overcome random generation problem. Genetic Algorithm (GA) is used to find the optimal initial weights based on learning using Mean Square Error as objective function. The initial weights using GA is expected to be stable and better than those generated. The experimental research showed that genetic algorithm can be used to optimize the performance of backpropagation neural network. The optimal initial weights from genetic algorithm is more stable than the initial weights from regular method. The classification accuracy of genetic algortihm and neural network is also higher than regular method. This indicated GA method is promising to increase the neural network performance and can be applied in various real problem.
Keyword: neural network, genetic algorithm, optimation, backpropagation, classification

Judul: Jaringan Syaraf Tiruan dan Algoritma Genetika dalam Pemodelan Kalibrasi (Studi Kasus: Tanaman Obat Temulawak)
Abstrak: The problems in prediction of calibration model are multicolinearity and the number of variables is larger than the number of observations. Principal Component Analysis-Artificial Neural Network-Genetic Algorithm (PCA-ANNGA) models were applied for the relationship between sample of concentration which is limited and transmittance data which is in large dimensions. A large number of variables were compressed into principal components (PC’s). From these PC’s, the ANN was employed for prediction of concentration. The principal components computed by PCA were applied as inputs to a backpropagation neural network with one hidden layer. The models was evaluated using GA for the best network structure on hidden layer. Root Mean Square Error (RMSE) for 80% training set and 20% testing set are 0.0314 and 0.5225, respectively. Distribution of data according to the percentage of training data and testing data were also very influential to obtain the best network structure with the smallest RMSE achievement. The best model for these methods is two layers Neural Network with eight neuron in the hidden layer.
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Judul: Development of Antioxidant Film from Basil Seed (Ocimum citriodourum) Mucilage Incorporated with Thyme Essential Oil.
Abstrak: The objectives of this research was to evaluate the effects of thyme essential oil addition on physical properties and antioxidant activity of lemon basil seed mucilage film. Lemon basil is a common name for the culinary herb (Ocimum citriodourum). This research project investigated the properties of an edible film based on lemon basil seed mucilage (LBSM) incorporated with thyme essential oil (TEO). LBSM (0.4% w/v) films were prepared by adding glycerol as plasticizers at the concentration of 30% w/w based on the weight of LBSM and then incorporated with TEO for antioxidant properties. LBSM films were given different concentrations of TEO (0%, 1%, 2% and 3% v/v) (0% as the control). The result showed that films with 3 % TEO had the highest water vapor permeability (WVP) (3.27±0.38 x10-4g mm/m2d kPa), while the control film showed the lowest WVP (1.36±0.28 x10-4g mm/m2d kPa). Water solubility were decreased with the increase in TEO concentration (p<0.05). 1% TEO films showed the highest tensile strength (5.17±0.54MPa) but lower % elongation at break (11.28±1.86%) compared to the other two films (p<0.05) (excluding the control). Scanning electron microscopy showed that the microstructure of the TEO LBSM films had a critical effect on its physical properties, further supporting the tensile strength and WVP results. The 3% TEO film exhibited the highest radical scavenging activity on DPPH (3.3±0.04 % inhibition) (p<0.05) while the others were very low and had slight difference. Increasing the amount of TEO will increase the antioxidant activity, but further increasing the concentration of TEO will also weaken the physical properties of the film.
Keyword: Lemon basil seed mucilage, edible film, antioxidant, thyme essential oil, film properties