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: Optimasi Jaringan Syaraf Tiruan Dengan Algoritma  Genetika Untuk Peramalan Curah Hujan
Abstrak: Informasi tentang banyaknya curah hujan sangat berguna bagi para petani dalam mengantisipasi kemungkinan terjadinya peristiwa-peristiwa ekstrim (kekeringan dan kebanjiran) yang akan berakibat kegagalan dalam proses produksinya. Dengan demikian, ketersediaan informasi ini memerlukan suatu metode peramalan curah hujan yang akurat. Beberapa penelitian yang sudah dilakukan belum memberikan hasil yang memuaskan. Algoritma genetika standar adalah metode yang digunakan untuk optimasi konfigurasi neuron pada lapisan tersembunyi dalam Jaringan Syaraf Tiruan (JST) ini. Teknik pembelajaran JST yang digunakan dalam metode peramalan curah hujan ini adalah JST propagasi balik standar dengan arsitektur banyak lapis yaitu satu lapisan input, satu lapisan tersembunyi, dan satu lapisan output. Keakuratan hasil prediksi JST diukur berdasarkan R2 dan RMSE-nya. Ujicoba terhadap sistem telah dilakukan JST dalam peramalan curah hujan dan hasilnya dibandingkan dengan metode principal component regression (PCR) dan JST propagasi balik standar dengan hasil terbaiknya dengan jumlah neuron 9 dan laju pembelajaran 0.02. Hasil peramalan curah hujan menggunakan metode PCR menghasilkan R2 sebesar 63%, sedangkan peramalan dengan menggunakan metode jaringan syaraf tiruan propagasi balik menghasilkan R2 sebesar 74%, dan JST yang dioptimasi menjadi 87%. Hal ini menunjukkan adanya peningkatan R2. Berdasarkan ujicoba tersebut dapat diperoleh kesimpulan bahwa optimasi JST dengan algoritma genetika dapat digunakan untuk memperbaiki tingkat pendugaan curah hujan dengan menggunakan data GCM daripada metode PCR dan JST propagasi balik standar.
Keyword: 

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