Energy saving in lighting system with fuzzy logic controller which uses light-pipe and dimmable ballast

Approximately, 20% of the electricity consumed in the world is spent for lighting. More efficient utilization of the sun, as a natural source of light, for lighting would save electricity used for lighting. The aim of this study is to illuminate a windowless room via a light-pipe and dimmable electronic ballasts. Light-pipe is used for the illumination of the space during the daytime. In case of inadequate daylight, artificial lighting is made via dimmable electronic ballasts and fluorescence lamps. Artificial lighting is supervised by a fuzzy logic control system to keep the illumination level at 350 lux. When there is a motion in the room, the system works with the message of the motion sensor, which, thereby, enables energy saving. Additionally, dimming the lamps result in conversation of the electrical energy used for illumination. After the experimental studies, 350 lux value targeted in the work plane is achieved with +/- 10 lux error. (c) 2013 Elsevier B.V. All rights reserved

Detection of ferroresonance phenomenon for the west anatolian electric power network in Turkey

Ferroresonance is an electrical phenomenon in nonlinear character, which frequently occurs in power systems containing saturable transformers and single or more-phase switching on the lines for the disjunction of the loads. In this study, the ferroresonance phenomena are considered under the modeling of the West Anatolian Electric Power Network of 380 kV in Turkey. The ferroresonance event is carried out using the switching to remove the loads at the end of the lines. In this sense, two different cases are considered. Firstly, the switching is applied at the 2nd second and the ferroresonance effects are observed between the 2nd and the 4th second of the voltage variations. As a result, the ferroresonance and non-ferroresonance cases observed before the ferroresonance, are compared with each other using the Fourier transform techniques. Hence, the properties of the ferroresonance event, which are defined between the 100 and 200 Hz, are presented in the frequency domain

Manufacturing of a portable electrospinning gun for biomedical applications

Electrospun patches have attracted interest in different biomedical fields, including tissue engineering and drug delivery. Portable electrospinning guns promise faster and more practical interventions in these areas. In this article, the design, construction and testing of a portable electrospinning gun are described to produce fiber and particle products. Results were discussed depending on the electrospinning gun\"s working system and properties of the products. The electrospinning gun system could have a high voltage of up to 30 kV. Also, no heating problems were encountered during high voltage values. Due to the uniformity, reproducibility and tunability of the produced PCL and PMSQ fibers, it can be said that electrospinning gun can be used in nanotechnology, drug delivery systems and wound dressing applications

A new approach for examination of performance of interior lighting systems

This paper presents a new approach for examination of insufficiency of a current lighting system and for performing maintenance plans of a lighting installation. Thus, a numerical algorithm based on finite element method (FEM) that ensures the required accuracy for illuminance calculations according to international lighting standards was developed. Experimental measurements were recorded in a controlled environment for the purpose of measuring the effectiveness of the algorithm. The average illuminance calculated according to CIBSE Code 1994 published by the Chartered Institution of Building Services Engineers (CIBSE) was obtained by error of 5.3% compared to the experimental measurements. Illuminance values of 894 points were calculated as 0.3% error according to the actual experimental measurements by proposed numerical algorithm that uses 36 pieces measurement data. Less experimental measurements provided more accurate results. The results obtained indicate that the suggested numerical model is very effective and usable in calculations of illuminance. In this way, this model will eliminate the requirement for long experimental measurements in lighting system controls that must be carried out periodically. (C) 2014 Elsevier B.V. All rights reserved

Continuous wavelet transform for ferroresonance phenomena in electric power systems

The common characteristics of a nonlinear system are multiple equilibrium points, limit cycles, jump resonance and sub-harmonic generation. Ferroresonance is also a nonlinear electrical phenomenon, which occurs frequently in power systems including no-load saturable transformers, transmission lines and single/three phase switching. In this work, we modeled the 380 kV West Anatolian Electric Power Network of Turkey, by performing numerical simulations using MATLAB-Simulink Power System Block-set. We generated the signals that are characteristics to the ferroresonance in order to exhibit the emergence of the nonlinear phenomenon. In addition, using the continuous wavelet transform (CWT), we observed the behavior of the ferroresonance both in time and frequency domains. Using the results of the CWT and Power Spectral Density (PSD) applications, the ferroresonance is determined from the emergence of the over voltage changes and the inter-harmonics of between +/- Delta integral Wand +/- Delta integral depending on frequency resolution +/- Delta integral. (C) 2012 Elsevier Ltd. All rights reserved