The rapid change and development in human life, information technology, and the increase in using home gadgets, modern appliances, and electric cars, leads to more dependency on electrical resources and consecutive increase in CO2 emission from generation plant. The current world issue is on how to save the energy by reducing the consumption and decreasing global warming. In this research, Smart Home Energy Management System (SHEMS) has been developed to operate home appliances in an optimum approach. It is aimed at reducing the consumption energy by detecting the residents' activity and identifying it among three states: Active, Away, or Sleep. The SHEMS is designed with an algorithm that is based on Hidden Markov Model (HMM) in order to estimate the probability of the home being in each of the above states. The proposed system uses the WiFi technology for data transmission inside home and the GSM technology for external communication. The proposed system and its algorithm was successfully tested and 18% of energy saving were obtained.

We develop a simple new design for a multi-band metamaterial absorber (MTMA) for radar applications. Computer Simulation Technology (CST) Studio Suite 2018 was used for the numerical analysis and absorption study. The simulated results show four high peaks at 5.6 GHz, 7.6 GHz, 10.98 GHz, and 11.29 GHz corresponding to absorption characteristics of 100%, 100%, 99%, and 99%, respectively. Furthermore, two different structures were designed and compared with the proposed MTMA. The proposed structure remained insensitive for any incident angle and polarization angle from 0° to 60°. Moreover, negative constitutive parameters were retrieved numerically. To support the simulated results, the proposed design was fabricated by using a computer numerical control-based printed circuit board prototyping machine and tested experimentally in a microwave laboratory. The absorption mechanism of the proposed MTMA is presented through the surface current and electric field distributions. The novelties of the proposed structure are a simple and new design, ease of fabrication, low cost, durability, suitability for real-time applications and long-term stability given the fabrication technique and non-destructive measurement method and very high absorption. The proposed structure has potential applications in C and X band frequency ranges.

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Abstract:The aim of this research is to design and implement a prototype of a home energy management system based on SMS service on GSM network. The proposed system can remotely monitor and control the home appliances using a mobile phone. The proposed system consists of a microcontroller connecting home appliances and lighting through sensors and relays. The microcontroller is also connected with a GSM module to support this system operate with an existing GSM network. This system is implemented using a GSM module that is connected with the personal computer representing the designed microcontroller. The home appliances, sensors and relays are modeled and simulated using Visual Basic programs. Software programs are developed and built into the personal computer to activate and control the home appliances according to received commands from the user mobile phone or to monitor and send their status to the mobile phone according to user request. The implemented system is tested practically with several cases at different times and it operates successfully with reasonable flexibility and secure operation. A good compatibility of the developed programs is achieved, since the system is running continuously without interruption under normal conditions of GSM network operation. It is found that the execution times for control and monitoring massages are 19.63 seconds and 19.33 seconds respectively.

In this paper, the characteristics of microstrip monopole antennas are studied firstly in free space. Secondly, the effects of the human body on the studied antenna's performance are investigated for wearable communications. Different patch shapes of microstrip monopole antenna are chosen to operate at two bands: industrial scientific and medical band (ISM) and ultra-wideband (UWB) for wearable applications. The studied antenna consists of a radiating element on one side of the substrate and a partial ground plane on the other side. The antenna is supposed to fabricate on cloth fabric whose relative dielectric constant is Ɛr =1.7. At the same time, the pure copper could be used as the conducting part representing both the radiating monopole and the partial ground plane. The software program of Computer Simulation Technology (CST) for Microwave Studio (MWS) is utilized to simulate the studied antennas. The obtained results have illustrated that in the free space, the proposed antennas of slotted hexagonal, rectangular, and circular shapes can operate from 2-12 GHz and of the bandwidth of 10.31 GHz, 10.19 GHz, and 9.67 GHz, respectively. The hexagonal antenna is selected and proposed to investigate the effects of the human body on its performance. The human body is simulated, and its effects on the performance of the proposed antenna are studied. The reflection coefficient, Voltage Standing Wave Ratio (VSWR), gain, and efficiency are found over that frequency range. The simulated results indicate that the human body effects are significant, and the proposed antenna showed to be a good candidate for wearable communications.