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Ionization Impact on the Air Cleaning Efficiency in the Interior

-342. [7] Wu, C.C., Lee, G.W.M. (2004). Oxidation of volatile organic compounds by negative air ions. Atmospheric Environment, 38 (37), 6287-6295. [8] Goodman, N., Hughes, J.F. (2004). The effect of corona discharge on dust mite and cat allergens. Journal of Electrostatics, 60 (1), 69-91. [9] Parts, T-E., Luts, A. (2004). Observed and simulated effects of certain pollutants on small air ion spectra: I. Positive ions. Atmospheric Environment, 38 (9), 1283-1289. [10] Tanaka, A., Zhang, Y. (1996). Dust settling efficiency and

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Electromagnetic Shielding Efficiency Measurement of Composite Materials

Electromagnetic Shielding Efficiency Measurement of Composite Materials

This paper deals with the theoretical and practical aspects of the shielding efficiency measurements of construction composite materials. This contribution describes an alternative test method of these measurements by using the measurement circular flange. The measured results and parameters of coaxial test flange are also discussed. The measurement circular flange is described by measured scattering parameters in the frequency range from 9 kHz up to 1 GHz. The accuracy of the used shielding efficiency measurement method was checked by brass calibration ring. The suitability of the coaxial test setup was also checked by measurements on the EMC test chamber. This data was compared with the measured data on the real EMC chamber. The whole measurement of shielding efficiency was controlled by the program which runs on a personal computer. This program was created in the VEE Pro environment produced by © Agilent Technology.

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Design and Development of ZigBee Based Instantaneous Flat-plate Collector Efficiency Measurement System

Design and Development of ZigBee Based Instantaneous Flat-plate Collector Efficiency Measurement System

Computing the efficiency of flat-plate collector is vital in solar thermal system testing. This paper presents the design of ZigBee enabled data acquisition system for instantaneous flat-plate collector efficiency calculation. It involves measurement of parameters like inlet and outlet fluid temperatures, ambient temperature and solar radiation intensity. The designed system has a base station and a sensor node. ZigBee wireless communication protocol is used for communication between the base station and the sensor node for wireless data acquisition. The wireless sensor node which is mounted over the collector plate includes the necessary sensors and associated signal-conditioners. An application program has been developed on LabVIEW platform for data acquisition, processing and analysis and is executed in base station PC. Instantaneous flat-plate collector efficiency is computed and reported.

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The Simultaneous Effect of the Operating Temperature and Solar Radiation on the Efficiency of Photovoltaic Panels / Jednoczesny Wpływ Temperatury Pracy Oraz Promieniowania Słonecznego Na Wydajnosc Ogniw Fotowoltaicznych

Abstract

The proper designing of PV systems requires the use of advanced building energy simulation techniques. It allows to design the best position of the PV array, as well as the right quantity of produced energy in different cases. On the other hand the PV efficiency is not only a constant value but changes according to temperature and solar radiation. This paper is devoted to estimate the simultaneous effect of both weather factors on PV efficiency. The task was achieved by numerical simulation and ESP-r software. Computer simulations have been carried out with the use of the Typical Meteorological Year data for Warsaw (52°N 21°E). The greatest influence of temperature on the efficiency of solar energy conversion was observed for crystalline silicon cells. The influence of the boundary conditions assumed in the study is ignored for amorphous silicon cells in the summer period and regardless of the material type in the winter period.

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Efficiency of Innovative Charge Pump versus Clock Frequency and MOSFETs Sizes

Abstract

Charge pumps are circuits that produce the voltage higher than supply voltage or negative voltage. Today, charge pumps became an integral part of the electronic equipment. The integration of charge pumps directly into the system allows manufacturers to feed a complex system with many specific power requirements from a single source. However, charge pump efficiency is reduced by many phenomena. This paper is focused on the question of efficiency of proposed variant of the charge pump. In this article, the efficiency dependence on a number of stages, output current, clock frequency and MOSFETs sizes was simulated by Eldo. The aim of this study is to determine the MOSFETs sizes and theirs influence to efficiency and the output voltage. Complex optimization of the charge pump circuit will follow in further text.

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Retention Efficiency of Vegetative Filter Strips for Nitrogen in Danjiangkou Reservoir Area, Central China

.09.039. [18] Faulkner JW, Zhang W, Geohring LD, Steenhuis TS. Nutrient transport within three vegetative treatment areas receiving silage bunker runoff. J Environ Manage. 2011;92:587-595. DOI: 10.1016/j.jenvman.2010.09.020. [19] Shin J, Gil K. Environ. Effect of rainfall characteristics on removal efficiency evaluation in vegetative filter strips. Earth Sci. 2014;72:601-607. DOI: 10.1007/s12665-013-2995-6. [20] Santin FM, Silva RVD, Grzybowski JMV. Artificial neural network ensembles and the design of performance-oriented riparian buffer strips for the filtering

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From Smart Metering to Smart Grid

– Economy 2010 , 18-20 May 2010. Bratislava, Slovakia: STU. [11] Chrapčiak, I. (2012). Ako ovplyvňujú straty energetickú efektívnosť? (How power losses influence the energy efficiency?). In ENEF 2012: 10 th International Conference , 16-17 October 2012, Banská Bystrica, Slovakia. [12] Chrapčiak, I. (2013). Cez selektívny Smart metering bližšie ku Smart grid. (By means of a selective smart metering nearer to the smart grid). In Trends of Electrical Power Engineering in European Context: International Conference , 17-18 April 2013, Špindlerův Mlýn, Czech

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Determination of the Lifetime Influence Upon the Conversion Efficiency of the Photovoltaic Silicon Solar Cells

. Schroder, Semiconductor material and device characterization, Third Edition, John Willey & Sons, Inc., 2006. [5] D.M. Chapin, C.S. Fuller, G.L. Pearson, A New Silicon p-n Junction Photocell for Converting Solar Radiation into Electrical Power, J. Appl. Phys. 25, 676, 1954. [6] N. Bateman, P. Sullivan, C. Reichel, J. Benick, M. Hermle, High quality ion implanted boron emitters in an interdigitated back contact solar cell with 20% efficiency, Proceedings of the 1st International Conference on Crystalline Silicon Photovoltaics, Energy Procedia, vol. 8, pp.509

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The Statistical Analysis of Relation between Compressive and Tensile/Flexural Strength of High Performance Concrete

statistical analysis of design methods efficiency in determining shear capacity of reinforced concrete beams, Proceedings of the 11th International Probabilistic Workshop, Brno, 2013. 14. S.S. Shapiro, M.B. Wilk., An analysis of variance test for normality, complete samples., Biometrica, vol.54, Great Brittan, 1965.

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Non-classical Signature of Parametric Fluorescence and its Application in Metrology

.E., McGill, W.J. (1982). Multiplication noise in the human visual system at threshold. Biological Cybernetics, 44, 157-165. [8] Migdall, A.L., Datla, R.U., Sergienko, A., Orszak, J.S., Shih, Y.H. (1995/96). Absolute detektor quantum-efficiency measurement ussing correlated photons. Metrologia, 32 (6), 479-483. [9] Brida, G., Degiovanni, I.P., Genovese, M., Rastello, M.L., Ruo-Berchera, I. (2010). Detection of multimode spatial correlation in PDC and application to the absolute calibration of a CCD camera. Optics Express, 18 (20), 20572

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