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In this paper, the design of a digital thermometer with clock is presented. The design was achieved using ATMEGA 328P PU Microcontroller Unit, MLX90614 Infrared Sensor for achieving contactless measurement (wireless) and the DS1307 Real Time Clock (RTC) for accurate time keeping during the measurement of this parameter.The MLX90614 is factory calibrated in wide temperature ranges from -40 ºC to 125ºC for the ambient temperature and -70 ºC to 382.19ºC for object temperature, while the DS1307 is a low-power clock/calendar with 56 bytes of battery-backed serial random access memory (SRAM). Power is supplied using a regulated 9 V DC battery. The microcontrollers and RTC chip are powered by 5 V DC. The temperature sensor and liquid crystal display (LCD) require 3.3 V DC for operation and are supplied by passing the 5 V DC through a variable resistor. The sensors output values are both fed into the microcontroller. While monitoring temperature and telling time, the microcontroller sends the measurements in form of digital signal to the LCDs for display.This design was compared with a standard infrared thermometer by taking the body temperature measurements of two individuals at different times of the day. It was observed from the results that the difference between the temperature readings of the two thermometers ranges from 0 to 1 °C

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Energy reach in the rural areas is still of major concern today especially in developing nations. Small-scale energy generation with stored compressed air is the focus of this work towards solving the energy deficit in remote rural environments through renewable sources. The method involves an experimental setup that harnessed energy from the sun through solar PV for isothermal compression and expansion of an air storage system to gain the advantages of low cost, longevity, and environmental friendliness of air storage in small scale electrical power generators. Results from a small, scalable, artificial air storage system of 360m3 show that one charge results in approximate temperature loss of 29oC for compression and 10oC for expansion (in a single cycle). A pressure charge of about 6bars from a compressor speed of 300rpm was also obtained and was able to maintain a constant alternator speed of 2500rpm on no load to produce electricity at 230Vac during expansion.  When advanced and standardized, the air storage could provide a medium for cheap electrical energy storage for small scale renewable sources and a means for electrical energy availability in remote rural environments.

Induction motors (IMs) are the most widely employed electrical motors due to their robust construction and adaptability. Due to their versatility and wide range of applications, it is crucial to examine the performance of these motors using a simple but thorough simulation model. In this study, we present the simulation models to conduct the DC test, the no-load test, and the locked rotor test on a three-phase induction motor using MATLAB/Simulink. These three tests are fundamental to determining the characteristics of a three-phase induction motor equivalent circuit. Furthermore, the authors extend the model to determine the starting current, starting torque, and breakdown torque of the motors under inquiry. The research further employs the right code in the MATLAB environment to ascertain the motors' torque-speed and current-speed properties. The results of the simulations are found to closely match the values achieved in real trials. Hence, this model can be employed to enhance teaching and research in the field of electrical machinery. Article Highlights This paper explains a computerized procedure employing MATLAB software to carry out vital tests on induction motors. The research shows that using the methods described in this paper, induction motors can be safely tested for their operating characteristics. The benefit of the computerized methodology described in this paper is that it provides a modelling tool and methodology to expand research on induction motors with high accuracy and reliability. The numerical method developed in this article is a suitable tool in teaching and education. Beyond the three common tests (dc test, no-load test and locked rotor test) to determine the equivalent circuit of induction motors, this paper further extends the research to use the simulation models to determine the starting current, starting torque and the breakdown torque of an induction motor as well as its torque-speed and current-speed characteristics.