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In this paper, the design of an automatic window is presented. The proposed window closes and opens automatically during and after a rainfall. The automatic system was developed with a focus on hospitals in order to allow medical staff and other supporting staff to concentrate on their primary responsibilities of taking care of patients. The system design includes a PIC16F877A microcontroller which gets activated when a moisture detector sensor sends a high logic signal to it. The microcontroller executes its embedded program by activating the stepper motor through a ULN2003 current-dependent integrated circuit (IC) chip resulting in stepwise control of the window. Hence, the window is automatically closed when rainfall is detected but opens and remains open when no rain is detected. We intend to extend our design to automatic opening and closing of the windows at others times in addition to during and after rainfall; for instance, window opening and closing every day at specific times in the morning and evening respectively.

The existence of phase noise in virtually every digital communications system poses a serious challenge to system designers especially as system complexity increases. Communication system complexity could be attributed to the modulation techniques adopted and the circuitry employed in achieving such modulations. This work investigates the impact of phase noise on the Symbol Error Rate (SER) of the different Quadrature Amplitude Modulation (QAM) schemes.  MATLAB simulation technique is adopted for the work and the results of the simulations show that as the phase noise is increased negatively, all the QAM schemes investigated show a reduction in SER and at a point, records a zero error. The value at which the schemes record this zero symbol error rate increases as the complexity of the scheme increases. So, higher order QAM schemes accommodate more symbol errors than the lower orders. The results also show that hard decision decoding has the worst performance index, irrespective of the QAM scheme, when compared with soft decision decoding.

Energy, which is required to run space satellites, is as old as space technology itself. The location of these satellites has made it more applicable for unconventional means of energy generation to run them. The Sun being the universal and greatest source of all forms of energy, as well as the closest energy source to space satellites, has been so appropriately trapped using solar cells. Solar power satellites are designed to capture solar energy and transmit that energy to receiving stations using wireless power transmission mechanism. This paper is written to rehearse the immediate and associated usefulness of solar energy trapped from space as an alternative for electricity generation for the future; it is also an attempt to appraise the prospects of this scientific conviviality.

This paper presents the design and implementation of a compact home security system. The use of security systems in today’s home where safety is an important issue cannot be over emphasized. The high crime rates and domestic hazards has brought up the need to take proper measures to prevent intrusions and hazards. It is in this regard that the design and implementation of a compact home security system based on the Global System for Mobile communication (GSM) comes in. Previous designs have used finger print protection, password protection, speech recognition, sensors with buzzer alarms, SMS and e-mail alerts but the designs were with so much complexities as well as at a cost disadvantage. The system presented here is of a minimal cost and simple design, it consists of one motion sensor, one temperature sensor, and one gas sensor.  The system was designed using the ATMEGA 8 microcontroller which controls the sending of SMS to the authorized number. The motion sensor (infrared) detects the movement of people entering the house and when there is a detection of an intruder the owner is notified through an SMS. The temperature sensor in this system also initiates an SMS to the owner when the temperature exceeds a particular value. The gas sensor also works in similar manner when it detects smoke and gas thereby sending SMS alert to the owner of the house. The respective sensors detected the compromise in each situation and sent the corresponding SMS to the user. This device therefore helps to prevent intruders, accidents arising from harmful gases and fire outbreaks in  homes, offices and industries.