N. N. Ismail

Clutter modeling for forward scatter radar (FSR) micro-sensor network with ultra high frequency (UHF) band

The clutter model for ultra high frequency (UHF) band for forward scatter radar (FSR) is developed in this paper using Log-Logistic distribution. The model follows maximum likelihood estimation (MLE) approach in finding the parameters for the distribution as well as root mean square error (RMSE) of the data between the clutter signal and statistical model as the goodness of fit (GOF) test. The model is then compared to four different distribution models, which are Log-Normal, Gamma, Weibull and Nakagami. The results of the comparisons show that Log-Logistic model best fits the clutter signal.

Skills Retention in Basic Offshore Safety and Emergency Training (B.O.S.E.T)

This chapter investigates the basic offshore safety and emergency training (B.O.S.E.T) skills retention phenomena among offshore professionals. To identify B.O.S.E.T skills retention, the researchers developed a role-play scenario test which is based on brace positions and heat escape lessening posture (H.E.L.P). The test was conducted over a period of 6 months with 38 offshore professionals. Analysis of the test data suggests that B.O.S.E.T skills retention depreciate with time at a rate of 24 % within the first 6 months. Skills level was estimated to be at 70 % within 9 months from the initial B.O.S.E.T training. Further forecast analysis suggests that the B.O.S.E.T skills level will be at 50 % by the end of 3 years. The research postulates that the current B.O.S.E.T refresher system maybe sufficed to ensure that B.O.S.E.T skills is sustained at an acceptable level within the 3 years period.

A miniaturized 878 MHz slotted meander line monopole antenna for ultra high frequency applications

A slotted meander line printed monopole antenna for low frequency applications of 878 MHz is presented. The novelty of the design is obtained by evaluating numerous slots and meander line that produces a new structure of double E-shaped meander line antenna backed by a defected partial ground plane. The operating frequency of the conventional printed monopole antenna is greatly reduced by the presence of the slots and meander line which lead to the reduction of the antenna size. The size reduction of 70% compared to the conventional reference antenna is achieved in this study. The antenna has a simple structure and small antenna size of 46.8mm × 74 mm or 0.137λ0 × 0.217λ0. The antenna has been fabricated on a low-cost FR4 substrate and measured to validate the simulation performances. Measured results display that the proposed antenna produces omnidirectional radiation pattern of impedance bandwidth of 48.83 MHz and the maximum gain of −1.18 dBi.

Measurement, processing and modeling of a tropical foliage clutter using Forward Scatter Radar micro-sensor network with VHF and UHF bands

This paper starts with description of a tropical foliage clutter measurements conducted at Forest Research Institute Malaysia (FRIM) using Forward Scatter Radar (FSR) with very high frequency (VHF) and ultra high frequency (UHF) bands. A clutter model is developed based on the characteristics of the measured clutter signal. This model will be used as a reference clutter signal in order to eliminate the effect of clutter during detection and classification process. Five types of statistical distribution are used to model the clutter signal namely Gamma, Log-Normal, Log-Logistic, Weibull and Nakagami. The models are then being compared and tested using root mean square error (RMSE) method to find the best distribution model that satisfies to represent the clutter signal. Gamma distribution model is found to be the best model for tropical foliage clutter.