Judul: Pengembangan model probabilistic neural network (PNN) pada pengenalan kisaran usia dan jenis kelamin berbasis suara
Abstrak: Voice signal can be used to represent a speaker. Voice can also be used to recognize the age range and the gender of the speaker, because of the difference in frequency of the voice signal for different age and gender. Age range for this experiment is divided into children (8-10 years old), teenagers (12-17 years old) and adults (30-50 years old). We performed feature extraction to obtain a representation of the speaker using Mel-Frequency Cepstrum Coefficient (MFCC). MFCC is used with 13, 20, 26 coefficients. Probabilistic Neural Network (PNN) is used as the feature matching model. The PNN model is constructed from three different proportions of TRD (Training data) : TSD (Testing data) (25%:75%, 50%:50%, 75%:25%). MFCC with 26 coefficient gives the best accuracy of 93.47%. The proportion of 75% (TRD) : 25% (TSD) also gives the best accuracy of 94.22%. PNN-age and PNN-gender identification result in an accuracy of 91.26%. Specifically, PNN accuracy percentage for male and female are 92.26%, and 95.20%, respectively, while for children, teenagers and adults the accuracies are 99.85%, 92.28% and 95.57%, respectively. In conclusion, the average of accuracy for all categories is 91.26%. The experiment using the voice of male-teenagers gives the worst accuracy, which is caused by the overlapping frequencies of voice in children, teenagers and adults.
Keyword: Voice identification, PNN model, MFCC, Age-identification, Gender-identification

Judul: Pengenalan Suara Berdasarkan Usia dan Jenis Kelamin Menggunakan Algoritme Support Vector Machine (SVM)
Abstrak: Voice recognition using computers is made possible due to the unique characteristics and frequencies that each voice possesses. These vocal characteristics can be grouped according to gender (male or female) or age (child, teenager, or adult). The purpose of this research is to identify individual voices that have been placed within one of the groups based on age and gender. The data used comes from the research of Fransiswa (2010) and consists of six classes: boys (AL), girls (AP), teenage boys (RL), teenage girls (RP), men (TL), and women (TP). The method used to extract vocal characteristics was the Mel Frequency Cepstrum Coefficient (MFCC) and pattern recognition was performed using a Support Vector Machine (SVM) with several variations of the kernel such as Linear, Polynomial, and Radial Basis Function (RBF). The parameters affecting the MFCC process include: The value of the coefficients, overlap, time frame, and the rate of sampling. The average highest accuracy value of 98,24% was obtained using the RBF Kernel
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Judul: Hydroxyapatite-Chitosan Composite Coating on Stainless Steel 316 to Improve Corrosion Resistance
Abstrak: Metals that were used in bone implantation should have good corrosion resistance that were not easily corroded when implanted into the body. Metal corrosion resistance of stainless steel 316 can be enhanced through the metal coating by hydroxyapatite-chitosan composite with composition ratio of hydroxyapatite (gram) and chitosan 3% (mL) 0.2:0, 0.2:0.1, 0.2:0.5, 0.2:1.0, and 0.2:1.5. Besides improving the corrosion resistance of metal, the presence of chitosan also maintain the position of hydroxyapatite on metal surfaces. Corrosion resistance increases with increasing amount of chitosan added and the best composition of hydroxyapatite-chitosan composite was 0.2:1.0.
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