A lot of low voltage output applications require relatively high input voltage, e.g., 48 V, 100 V, etc., because high voltage is more efficient in distributing current. To minimize the power loss and protect the output load from possible over-voltage due to the failure of the semiconductor devices, a step-down isolation transformer is required in this type of low voltage power supply design. In...

We present a novel design of a single-cylinder free piston engine linear generator (FPELG) incorporating a linear motor as a rebound device. A systematic simulation model of this FPELG system was built containing a kinematic and dynamic model of the piston and mover, a magneto-electric model of the linear generator, a thermodynamic model of the single-cylinder engine, and a friction model betwe...

This paper aims at estimating the efficiency of hydroelectric power plants (renewable energy resources) and thermal power plant (non-renewable energy resources) in Iranian provinces. Data Envelopment Analysis (DEA) approaches is applied to estimate the efficiency. The network is modeled as a linear system with multiple inputs and one output. Fuel cost, labor force, operation cost are used as in...

As laid out in the National Airspace System (NAS) Operational Evolution Plan (OEP) [1], the Federal Aviation Administration (FAA) and the aviation community are planning to make significant investment in NAS improvements over the next ten years. These enhancements involve implementation of Communication, Navigation and Surveillance (CNS) technologies, and automation of ground systems in order t...

Efficiency and evaluation is one of the main and most important demands of organizations, companies and institutions. As these organizations deal with a large amount of data, therefore, it is necessary to evaluate them on the basis of scientific methods to improve their efficiency. Data envelopment analysis is a suitable method for measuring the efficiency and performance of organizations. This...

The effects of composition and p-doping profile of the AlGaN:Mg electron blocking layer (EBL) in 310 nm ultraviolet B (UV-B) light emitting diodes (LEDs) have been investigated. The carrier injection and internal quantum efficiency of the LEDs were simulated and compared to electroluminescence measurements. The light output power depends strongly on the temporal biscyclopentadienylmagnesium (Cp...

Data Envelopment Analysis (DEA) is a mathematic technique to evaluate the relative efficiency of a group of homogeneous decision making units (DMUs) with multiple inputs and outputs. The efficiency of each unit is measured based on its distance to the production possibility set (PPS). In this paper, the BCC model is used in output-oriented. The average return on profit as output and the covaria...

Optimising the output power of a photovoltaic panel improves the efficiency of a solar driven energy system. The maximum output power of a PV panel depends on atmospheric conditions, load profile and the tilt and orientation angles. In this study, an experimental analysis of maximizing output power of a PV panel is carried out, based on the use of existing equations of tilt and orientation angl...

An increased risk of falls in the elderly is associated with decreased muscle mass and strength lower limbs. The Otago Exercise Regimen (OEP) a moderately challenging walking, flexibility, strengthening, balancing exercise regimen. Program has been demonstrated to reduce incidence individuals by improving balance muscular strength. This research sought ascertain how influenced limb older women....

since data envelopment analysis (dea) introduced in 1970s, it has been widely applied to measure the efficiency of a wide variety of production and operation systems. recently dea has been extended to examine the efficiency of decision making units (dmus) with two-stage network structures or processes, where the outputs from the first stage are intermediate measures that make up the inputs of t...