by developing the level of life in societies, the need for new resources of energy becomes more important. in almost all cases, the aim is to convert one form of energy to the electrical form. with advances of technology and use of new electric and electronic devices and gadgets, the need for electrical energy is increasing and providing stable and continuous electric power becomes very importa...

One unintended eeect of the growth of the Internet is increased energy usage by servers and the infrastructure supporting them. This paper promotes a research agenda to improve the energy eeciency of Internet server sites. This goal is timely as the costs of energy usage and our vulnerability to energy supply disruptions become increasingly evident. In particular, we propose energy-conscious se...

The reduction trend of modern microsystem power consumption is balanced by the constant growth of complexity. Traditional batteries are, therefore, no longer sufficient for many applications, since they cannot guarantee a long enough life time [1]. By harvesting energy from the environment, such systems could work for nearly infinite time without the need of replacing batteries. In this paper w...

This paper presents a simulation and mathematical model of stand-alone solar-wind-diesel based (HES). A power management system is designed for multiple energy resources in a stand-alone hybrid energy system. Both Solar photovoltaic and wind energy conversion system consists maximum power point tracking (MPPT), voltage regulatio basic power electronic interfaces. An additional diesel generator ...

Renewable energy provides twenty percent of electricity generation worldwide. Hydroelectric power is the cheapest way to generate electricity today. It is a renewable source of energy and provides almost one-fifth of electricity in the world. Also, it generates electricity using a renewable natural resource and accounting for six percent of worldwide energy supply or about fifteen percent of th...

Radio Frequency (RF) Energy Harvesting holds a promising future for generating a small amount of electrical power to drive partial circuits in wirelessly communicating electronics devices. Reducing power consumption has become a major challenge in wireless sensor networks. As a vital factor affecting system cost and lifetime, energy consumption in wireless sensor networks is an emerging and act...

introduction: this study aimed to assess the scanning electron microscope (sem) analysis of tooth surface irradiated by erbium:yttrium–aluminum–garnet (er:yag) laser with various parameters. methods: number of 25 extracted human third molars free of caries were used in this study. the teeth were put into 5 groups for laser irradiation as follows: group 1 (power: 0.5 w, energy: 50 mj); group 2 (...