Fractal dimension (FD) is a very useful metric for the analysis of image structures with statistically self-similar properties. It has applications in areas such as texture segmentation, shape classification and analysis of medical images. Several approaches can be used for calculating the fractal dimension of digital images; the most popular method is the box-counting method. It is also very challenging and difficult to classify patterns in high resolution computed tomography images (HRCT) using this important descriptor. This paper applied the Holder exponent computation of the local intensity values for detecting the emphysema patterns in HRCT images. The absolute differences between the normal and the abnormal regions in the images are the key for a successful classification of emphysema patterns using the statistical analysis. The results obtained in this paper demonstrated the effectiveness of the predictive power of the features extracted from the Holder exponent in the analysis and classification of HRCT images. The overall classification accuracy achieved in lung tissue layers is greater than 90%, which is an evidence to prove the effectiveness of the methods investigated in this paper.

The amount of absorbed X-ray dose by a particular human at a single exposure can have some effect on DNA. There is therefore the need to apply the correct range of dose to patients during X-ray. X-ray films from exposed adult patients were collected for use at a hospital. Each of the film’s optical densities was measured at various spots on the film and averaged as the mean. An estimated range of absorbed dose for the films was found to be between 0.83 mGy to 8.86 mGy. The results were compared with the 1.2 mGy value, which is the absorbed dose that should not be exceeded during an exposure, so that the DNA is not altered. The doses above this value are capable of doing harm to the human DNA. As a result, that ionizing radiation of low dose values can produce an effect on human DNA, hence this occurrence may be checked with a research work of this nature.

The sensitivity of radiographic films is an important factor to the clarity and accuracy of X-ray exposure to patients during treatment or diagnostic periods. It is therefore important to do a thorough analysis of the sensitivity of the radiographic film before and after exposure to enhance the Quality Assurance (QA) and the Quality Control (QC), of the exposure procedures. The optical densities (OD) of each film was measured, with a densitometer model MA 5336, made by GAMMEX. These values were then converted to the absorbed dose (X mGy), which is the amount of dose absorbed by each patient. The optical density versus the dose curve, followed the expected pattern, showing a good prediction from the General model, that the films employed in the exposures were of good quality and standard. Hence the optical density versus dose sensitometric curves depicts the outcome of the various films sensitivity after an exposure to the X-ray radiation through the patients.

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In this study, measurement of radiofrequency exposure due to cellular transceiver base station antennas was carried out. Both far and near field measurements of electric field and magnetic field level were made around selected transceiver base station antennas in selected South-South States Nigeria, with the aid of frequency-dependent equipment (CORNET, Electrosmog meter ED78S EMF RF/LF Dual mode model). The results obtained were analysed using thermal related indices such as specific absorption rate (SAR) with peak value in cerebrospinal fluid-CSF (0.095358W/kg), temperature rise with peak also in CSF (0.008381 oC). These results were compared with threshold values of 2 W/kg and 0.08 W/kg for SAR (over the head and whole body respectively), and 1oC for temperature rise as set by International Commission of Non Ionizing Radiation Protection (ICNIRP). The results indicate that none of the network operators in the study area have SAR above the recommended threshold value with the worst case observed in Calabar.