ABSTRACT
AR [autoregressive modeling] and ARMA [autoregressive moving average modeling] are very popular in modeling processes, in the present work they were used to simulate the EEG [brain activity] to investigate which of them is better for simulating the brain activity. Two groups were investigated; control group and Epileptic group [patients suffer from brain disorder and convulsions], it was found that AR model is efficient to simulate the brain activity, because of its stability and its coefficients of variation fluctuate in a limited range. ARMA model showed higher values for the calculated variation coefficient of model parameter. The coefficient of variation was reached 182% for 80% of the model coefficients. This variation was obvious over the studied time intervals. In addition, ARMA model needs more time of computation, therefore AR model is preferred to simulate the brain activity
ABSTRACT
The objectives of the present study were to determine the magnitude of child dental health problems in Al Hassa and to study geographical and sex variation of such problems. A Cross-sectional study was done in Al Hassa using multistage random sample technique. Out of 33 primary schools, 3732 children with mean age of 10.6 [1.5 SD] years were examined. Dental decay, filled and missed teeth were found in 76.2 percent, 4.3 percent and 3.1 percent of the children, respectively. DM FT index [decayed, missed and filled teeth] was 2.96 and restorative treatment need was very high [98 percent]. Periodontal disease was found in 45.3 percent of the children, oral manifestation fluorosis were found in 32.7 percent and malocclusion problems were found in 9.2 percent of the children, Studying geographical and sex variations showed that dental caries and fluorosis were significantly higher in villages than in towns [P<0.01], while periodontal disease and malocclusion were more prevalent among children living in towns,but the difference was not statistically significant [p>0.05].In general the prevalence of the four dental problems were higher among boys than girls. A combined approach of treatment and effective public health preventive program is recommended for proper management of dental problems in Al Hassa