Electromagnetic radiation towards adult human head from 900MHz handheld mobile phone

Electromagnetic radiation produce by mobile phone and the relationship with the human's health is not a new issue nowadays. Since the used of mobile phone had increased rapidly over the past few years, people are becoming more concern with their health when dealing with the so-called electromagnetic radiation. This type of radiation would leads to heating of body tissue at specific rate called the thermal radiation. Thermal radiation depends on the frequency of the energy, the power density of the radio frequency field that strikes the body and the polarization of wave. This paper will discuss on the result collected from the thermal radiation generated by handheld mobile phone with frequency of 900 MHz towards adult human head. The analysis is conducted in a laboratory with average of 45 minutes talking hour with two different types of mobile phone, internal and external antenna. The results show an increased of heat especially at the place near the ear skull after 45 minutes of operation. When comparing both different types of mobile phone, mobile phone with external antenna produce more heat compared to mobile phone with internal antenna

Full Reference Image Quality Metrics and their Performance

This paper mainly aims to study the performance of objective assessment methods of image quality. It take into consideration the correlations between each objective assessment and the subjective assessment in order to determine objective test performance. Three objective assessment methods used in this study are the Structural Similarity (SSIM) index, the Peak Signal-to-Noise Ratio (PSNR) and the Mean Squared Error (MSE) calculating algorithm. The resulting data indicate what type of objective assessment was most suitable for which type of impairment imposed upon an image. This is clarified using the Pearson Correlation Coefficient as described in the paper. As an overall, SSIM index had the best correlation characteristics to the subjective assessment, followed by the MSE calculating algorithm. From this study, a better understanding of the requirements for developing an efficient image quality assessment method was gained

A Review of MRI Acute Ischemic Stroke Lesion Segmentation

Immediate treatment of a stroke can minimize long-term effects and even help reduce death risk. In the ischemic stroke cases, there are two zones of injury which are ischemic core and ischemic penumbra zone. The ischemic penumbra indicates the part that is located around the infarct core that is at risk of developing a brain infarction. Recently, various segmentation methods of infarct lesion from the MRI input images were developed and these methods gave a high accuracy in the extraction and detection of the infarct core. However, only some limited works have been reported to isolate the penumbra tissues and infarct core separately. The challenges exist in ischemic core identification are traditional approach prone to error, time-consuming and tedious for medical expert which could delay the treatment. In this paper, we study and analyse the segmentation algorithms for brain MRI ischemic of different categories. The focus of the review is mainly on the segmentation algorithms of infarct core with penumbra and infarct core only. We highlight the advantages and limitations alongside the discussion of the capabilities of these segmentation algorithms and its key challenges. The paper also devised a generic structure for automated stroke lesion segmentation. The performance of these algorithms was investigated by comparing different parameters of the surveyed algorithms. In addition, a new structure of the segmentation process for segmentation of penumbra is proposed by considering the challenges remains. The best accuracy for segmentation of infarct core and penumbra tissues is 82.1% whereas 99.1% for segmentation infarct core only. Meanwhile, the shortest average computational time recorded was 3.42 seconds for segmenting 10 slices of MR images. This paper presents an inclusive analysis of the discussed papers based on different categories of the segmentation algorithm. The proposed structure is important to enable a more robust and accurate assessment in clinical practice. This could be an opportunity for the medical and engineering sector to work together in designing a complete end-to-end automatic framework in detecting stroke lesion and penumbra

Surface Analysis of Thermally Growth Ge Oxide on Ge(100)

The understanding of Ge oxidation is utmost importance in order to form the good quality dielectric/Ge interface in fabricating Ge Metal Oxide Semiconductor Field Effect Transistor (MOSFETs). In addition, the mechanism of Ge oxidation is still under intensive studies. For Silicon oxidation, Deal and Grove Model have been accepted to explain the Si Oxidation mechanism. The purpose of this paper is to report the mechanism of Ge oxidation at two different temperatures, 375 and 490°C and the detail of Ge oxide composition at Ge oxide/Ge interface. After wet chemical cleaning with HCl, the thermal oxidation was performed at temperature 375 and 490°C at atmospheric pressure. The thickness and composition of Ge oxide were measured with spectroscopic ellipsometry and x-ray photoelectron spectroscopy, respectively. It was observed that the n value extracted from a log-log plot of oxidation time versus oxide thickness was dependent on the oxidation temperature. The oxygen-deficient region was formed during thermal oxidation of Ge and the electronic states of suboxide component were observed in the region within 2.3eV above the top valence band. The novelty of this work is to investigate the kinetics oxidation of Ge and evaluate the composition of oxide layer after thermal oxidation that becomes useful information for the development of Ge MOSFETs

Visual Inspection of Acetic Acid (VIA) to Detect PreCancerous Cervical Cancer in Rural Areas of Sarawak

Introduction: Cervical cancer is still the leading cause of gynaecological cancer in Sarawak. Low awareness on cervical screening and logistic problems are the main reasons for delay in diagnosis, especially in rural areas. Although pap smear screening had been implemented for decades, failure to get early treatment and frequent defaulters are factors that need to be tackled for rural women. Objectives: The Sarawak Travelling Women Health Project is aimed to improve pre-cancerous cervical cancer detection in rural areas using the Visual Inspection of Acetic Acid (VIA) method. This project also helps to shorten the duration of follow up and treatment for patients with pre-cancerous lesion of cervix. Methods: Cervical screening campaigns outside Kuching areas were conducted from June until December 2018 by the Obstetrics and Gynaecology Department of Universiti Malaysia Sarawak (UNIMAS) in collaboration with Pink and Teal Empower, a Non-Government Organization. VIA was performed for all women below 50 years old. Patients with positive VIA were a colposcopy appointment and cervical biopsies are taken at the clinic. Results: During the campaign period, 83 out of 333 women were found to be VIA positive, but only 47 women turned up for the colposcopy. This high number of defaulters is mostly due to logistic reasons. Two cervical biopsies were confirmed as Cervical Intraepithelial Neoplasia (CIN) 2, 15 cases with CIN 1, one case of microglandular hyperplasia while 19 biopsies turned out to be cervicitis. The pickup rate for CIN during the outreach was about 20.4%. Conclusion: VIA is useful in low resource area with difficult access to tertiary centres as it enables faster diagnosis for CIN. However, proper training is needed to avoid false positive results and unnecessary intervention. To reduce the rate of defaulters, cervical biopsy for VIA positive women should be done in the field during the same setting

Review of Efficiency CMOS Class AB Power Amplifier Topology in Gigahertz Frequencies

This paper reviewed the efficiency of CMOS class AB power amplifier topology especially in gigahertz frequencies. CMOS class AB power amplifier is a compromise between class A and class B in terms of linearity and efficiency between 50% to 78.5%. However, CMOS class AB power amplifier cannot have good linearity and efficiency simultaneously due to the breakdown in gate-oxide voltage and effects from hot carrier. The breakdown of oxide prevents optimum drain signal and the effect from hot carrier will reduce the quality of the overall PA design. Several works from year 1999 to 2019 with different topology such as multiple gated transistor, cascode, feedforward linearization, differential circuit, transformer combining method with common source harmonic termination and combination of a dual-switching transistor with a third harmonic tuning technique are discussed and the performances of the power amplifier are compared. The best three CMOS class AB power amplifier topologies were chosen in terms of high efficiency. The topologies are two stages with integrated input and interstage matching, Doherty amplifier combined with drain modulation based architectures and self-biased cascode topology that obtained power added efficiency of 45%, 43% and 42%, respectively. Key performance indicators for class AB power amplifier include frequency, power added efficiency, gain and output power are also discussed in this paper