A review on electromagnetics (EM) exposure measurement techniques from base station

EM exposure in the range of non-ionizing radiations (NIR) which falls in the radio frequency up to 3GHz is mainly sourced from mobile phone base stations, broadcast towers and radar facilities. This reviews based on previous researcher obtained results and methods in order to determine the best technique to measure the exposure. Moreover, the estimation of exposure levels by considering the specification of the antennas installed and area of the base stations itself was also reviewed. It was found that numerous study of NIR exposure level has been conducted in other countries, while Malaysia has become aware of the importance. Most of the studies used field meter to carry out the measurement, and the exposure level obtained were far lower than the limit recommended by World Health Organization (WHO).Keywords: electromagnetic exposure level, base station, electric field strength, geographical information syste

Remote radiation monitoring system at uranium exploration site in Mkuju river

A project Report Submitted in Partial Fulfillment of the Requirements for the Degree of Master of Science in Embedded and Mobile Systems of the Nelson Mandela African Institution of Science and TechnologyUsage of radioactive materials in a number of countless activities has increased rapidly worldwide, thus, increasing Uranium exploration in different countries including Tanzania. As Uranium decays, it emits ionizing radiations, which has health risks associated with it. The major threats occur when ionizing radiations produced during uranium decay exceed their levels. Causing skin burns and acute radiation syndrome, though in the long-term cause cancer and cardiovascular disease, are the substantial health effects to mention a few. Thus real-time and remote monitoring of radiation at uranium mining sites is mandatory to ensure environmental and human safety. Radiation detectors are used to monitor radiation at uranium mining sites by frequently visiting however achieving real-time and remote monitoring is still the challenge. This method is time-consuming and the existing radiation detectors used in Tanzania are exported from developed countries and are expensive. This design science study presents an effective and affordable system for remote monitoring of radiation at uranium mining sites using internet of things (IoT) technology. The system used prototype methodology and the radiation detector was programmed by using ESP32 microcontroller board. Which through its inbuilt Wi-Fi it was able to send data to the cloud data storage. The Message Queuing Telemetry Transport protocol facilitated remote visualization of radiation levels from the cloud storage dashboard and the developed mobile application. The end-users monitored radiation data and received notifications in case of excess radiation through the developed mobile application. The internet of things technology facilitated the end-users to visualize and monitor radiation levels anytime and anywhere via the internet

Early Breast Cancer Diagnosis using Microwave Imaging via Space-Frequency Algorithm

Title from PDF of title page viewed June 6, 2017Thesis advisor: Deb ChatterjeeVitaIncludes bibliographical references (pages 48-56)Thesis (M.S.)--School of Computing and Engineering, University of Missouri--Kansas City, 2017The conventional breast cancer detection methods have limitations ranging from ionizing radiations, low specificity to high cost. These limitations make way for a suitable alternative called Microwave Imaging, as a screening technique in the detection of breast cancer. The discernible differences between the benign, malignant and healthy breast tissues and the ability to overcome the harmful effects of ionizing radiations make microwave imaging, a feasible breast cancer detection technique. Earlier studies have shown the variation of electrical properties of healthy and malignant tissues as a function of frequency and hence stimulates high bandwidth requirement. A Ultrawideband, Wideband and Narrowband arrays have been designed, simulated and optimized for high (44%), medium (33%) and low (7%) bandwidths respectively, using the EM (electromagnetic software) called FEKO. These arrays are then used to illuminate the breast model (phantom) and the received backscattered signals are obtained in the near field for each case. The Microwave Imaging via Space-Time (MIST) beamforming algorithm in the frequency domain, is next applied to these near field backscattered monostatic frequency response signals for the image reconstruction of the breast model. The main purpose of this investigation is to access the impact of bandwidth and implement a novel imaging technique for use in the early detection of breast cancer. Earlier studies show the implementation of the MIST imaging algorithm on the time domain signals via a frequency domain beamformer. The performance evaluation of the imaging algorithm on the frequency response signals has been carried out in the frequency domain. The energy profile of the breast in the spatial domain is created via the frequency domain Parseval’s theorem. The beamformer weights calculated using these the MIST algorithm (not including the effect of the skin) has been calculated for Ultrawideband, Wideband and Narrowband arrays, respectively. Quality metrics such as dynamic range, radiometric resolution etc. are also evaluated for all the three types of arrays.Introduction -- Buried object detection using EM waves -- Sensor design and analysis in FEKO -- Novel imaging algorithm -- Results -- Conclusion -- Appendi

Non-Thermal Effect Of The Brand And Generic Mobile Phones Radiofrequency Radiation On The Antioxidant And Histomorphology Of The Epididymis After Prolonged Whole-Body Radiation on Sprague Dawley Rat

Mobile phone usage has increased greatly over time, and there is also the proliferation of models by different manufacturers, some of which are known to produce popular brands while other manufacturers of unknown brands have been identified. So many health conditions have been associated with the radiation emitted from mobile phones and other communication gadgets. Such condition as glioma, schwannoma, and some degenerative tissue conditions has been reported by different researchers both on short and prolonged exposure. The IARC report on radiofrequency radiation as a human “possible carcinogen, group 2B” has also prompted much research on the effect of mobile phone radiofrequency radiation on humans. The mobile phone placement in the pocket, which is close to the male reproductive organ, and the possible radiation emission levels from different models by manufacturers prompted this study. The goal is to investigate the histological alterations, spermatic epididymal contents, and changes in oxidative stress indicators that may occur following prolonged exposure to mobile phone radiofrequency radiation. Forty (40) male Sprague Dawley rats were used for this study. They were grouped into eight groups equally, two (2) control groups and six (6) groups that were exposed to six different mobile phone models. The 8 hours of daily exposure for 6 months was done with phones in active mode. The finding showed a significant reduction of the mature sperms in the lumen of the epididymis. There was focal epithelial hyperplasia in two groups exposed to branded models. No degenerative epithelium was observed in the epididymis. There was also a significant reduction in the motility and sperm count of the exposed groups. The Superoxide dismutase (SOD) was significantly depleted across the exposed groups. There are isolated changes that result from individual phone models, but changes cannot be dichotomized into changes that result from branded or generic phones

RADIATION FROM DIFFERENT PARTS OF LAPTOPS

Radiation from laptop cannot be seen by the naked eyes, but it can pose real dangers to our health. If only we are a few feet away to our laptops, otherwise when laptops are placed and used directly on our laps, it exposes us to quite more intense radiation that are harmful. It has been said that the amount of radiation emitted by desktop computers is generally higher than that which is emitted from Laptop or notebook computers. And the use of small-sized components, a Light Emitting Diode (LED) or Liquid Crystal Display (LCD) are some of the main reasons why that is so. Furthermore, since these laptops are battery operated and this plays a major role in reducing the rate of radiation emitted from these portable computers. But internal parts of laptop heat up and radiate. There is a generation of Extremely Low Frequency (ELF)by laptop from storage and computing processing. Placing the laptop on the lap make to be very close to the genitals, skin and muscles. Prolonged exposure to this radiation may produce biological effects on human health. This work used Cell Sensor manufactured by Action Electronic, USA to detect ELF from fourteen (14) laptops and mini laptops. It was found that the keyboard of the laptop emitted highest value of ELF radiation while the back of the laptop had the lowest ELF radiation. The highest ELF at 0 cm for different parts measured are 5 mG, 5 mG,3.5 mG and 0.7 mG for laptop keyboard, mouse pad, fan and screen respectively. There is no ELF measured at the back of the laptops except in AMP with ELF of 0.1 mG at 0 cm. Mini laptops were observed emit less ELF radiation than laptops of size ranging from 14 inches – 17 inches. Therefore, the study suggested that less often the laptops are placed on the laps the more the health and safety of the users are guaranteed

Development of Novel Sensor Devices for Total Ionization Dose Detection

abstract: Total dose sensing systems (or radiation detection systems) have many applications, ranging from survey monitors used to supervise the generated radioactive waste at nuclear power plants to personal dosimeters which measure the radiation dose accumulated in individuals. This dissertation work will present two different types of novel devices developed at Arizona State University for total dose sensing applications. The first detector technology is a mechanically flexible metal-chalcogenide glass (ChG) based system which is fabricated on low cost substrates and are intended as disposable total dose sensors. Compared to existing commercial technologies, these thin film radiation sensors are simpler in form and function, and cheaper to produce and operate. The sensors measure dose through resistance change and are suitable for applications such as reactor dosimetry, radiation chemistry, and clinical dosimetry. They are ideal for wearable devices due to the lightweight construction, inherent robustness to resist breaking when mechanically stressed, and ability to attach to non-flat objects. Moreover, their performance can be easily controlled by tuning design variables and changing incorporated materials. The second detector technology is a wireless dosimeter intended for remote total dose sensing. They are based on a capacitively loaded folded patch antenna resonating in the range of 3 GHz to 8 GHz for which the load capacitance varies as a function of total dose. The dosimeter does not need power to operate thus enabling its use and implementation in the field without requiring a battery for its read-out. As a result, the dosimeter is suitable for applications such as unattended detection systems destined for covert monitoring of merchandise crossing borders, where nuclear material tracking is a concern. The sensitive element can be any device exhibiting a known variation of capacitance with total ionizing dose. The sensitivity of the dosimeter is related to the capacitance variation of the radiation sensitive device as well as the high frequency system used for reading. Both technologies come with the advantage that they are easy to manufacture with reasonably low cost and sensing can be readily read-out.Dissertation/ThesisDoctoral Dissertation Electrical Engineering 201

Study of radiation-tolerant integrated circuits for space applications

Integrated Circuits in space suffer from reliability problems due to the radiative surroundings. High energy particles can ionize the semiconductor and lead to single event effects. For digital systems, the transients can upset the logic values in the storage cells which are called single event upsets, or in the combinational logic circuits which are called single event transients. While for analog systems, the transient will introduce noises and change the operating point. The influence becomes more notable in advanced technologies, where devices are more susceptive to the perturbations due to the compact layout. Recently radiation-hardened-by-design has become an effective approach compared to that of modifying semiconductor processes. Hence it is used in this thesis project. Firstly, three elaborately designed radiation-tolerant registers are implemented. Then, two built-in testing circuits are introduced. They are used to detect and count the single event upsets in the registers during high-energy particle tests. The third part is the pulse width measurement circuit, which is designed for measuring the single event transient pulse width in combinational logic circuits. According to the simulations, transient pulse width ranging from 90.6ps to 2.53ns can be effectively measured. Finally, two frequently used cross-coupled LC tank voltage-controlled oscillators are studied to compare their radiation tolerances. Simulation results show that the direct power connection and transistors working in the deep saturation mode have positive influence toward the radiation tolerance. All of the circuit designs, simulations and analyses are based on STMicroelectronics CMOS 90 nm 7M2T General Process

Model Based On-Line Energy Prediction System for Semi-Autonomous Mobile Robots

Maximizing energy autonomy is a consistent challenge when deploying mobile robots in ionizing radiation or other hazardous environments. Having a reliable robot system is essential for successful execution of missions and to avoid manual recovery of the robots in environments that are harmful to human beings. For deployment of robots missions at short notice, the ability to know beforehand the energy required for performing the task is essential. This paper presents a on-line method for predicting energy requirements based on the pre-determined power models for a mobile robot. A small mobile robot, Khepera III is used for the experimental study and the results are promising with high prediction accuracy. The applications of the energy prediction models in energy optimization and simulations are also discussed along with examples of significant energy savings