TEC

About: TEC is a research topic. Over the lifetime, 5119 publications have been published within this topic receiving 84696 citations.

User-friendly and intuitive graphical approach to the design of thermoelectric cooling systems

Abstract: This study proposes a user-friendly graphical method for calculating the steady-state operational point of a thermoelectric cooler (TEC)-based active cooling system, including the heatsink role. The method is simple and intuitive and provides comprehensive information about the cooling system such as its feasibility, required heatsink, the TEC current, temperatures of the cold and hot sides, and coefficient of performance (COP). The method could help designers to examine and choose a thermoelectric module from catalogues to meet a specific cooling problem. To start using the method, designers need only the experimental TEC data provided by practically all manufacturers of such devices. The experimental results of this study verify the high accuracy of the proposed model and graphical approach.

Estimating the contribution from different ionospheric regions to the TEC response to the solar flares using data from the international GPS network

Abstract: . This paper proposes a new method for estimating the contribution from different ionospheric regions to the response of total electron content variations to the solar flare, based on data from the international network of two-frequency multichannel receivers of the navigation GPS system. The method uses the effect of partial "shadowing" of the atmosphere by the terrestrial globe. The study of the solar flare influence on the atmosphere uses GPS stations located near the boundary of the shadow on the ground in the nightside hemisphere. The beams between the satellite-borne transmitter and the receiver on the ground for these stations pass partially through the atmosphere lying in the region of total shadow, and partially through the illuminated atmosphere. The analysis of the ionospheric effect of a powerful solar flare of class X5.7/3B that was recorded on 14 July 2000 (10:24 UT, N22 W07) in quiet geomagnetic conditions (Dst = -10 nT) has shown that about 75% of the TEC increase corresponds to the ionospheric region lying below 300 km and about 25% to regions lying above 300 km. Key words. Ionosphere (solar radiation and cosmic ray effects; instruments and techniques) – Solar physics, astrophysics and astronomy (ultraviolet emissions)

Study of the ionospheric total electron content response to the great flare on 15 April 2001 using the International GPS Service network for the whole sunlit hemisphere

Abstract: The characteristics of the ionospheric response to the solar flare on Apr. 15, 2001 were studied using the total electron content (TEC) obtained at GPS observational stations in the whole sunlit hemisphere under International GPS Service for Geodynamics. It was found that the largest enhancement of the sudden increase of total electron content during this flare is similar to 2.6 TECU (1 TECU = 10(16) m(-2)). The effects of solar flare radiation on the ionosphere can be recognized even in the region at 0600 or 1800 LT. Owing to ionospheric scintillation, the TEC enhancement could not be derived from temporal TEC variation curves in high latitudes. On the other hand, the synoptic picture of the sunlit ionospheric response to the flare was obtained, and the results showed the relationship of TEC enhancements with solar zenith angles. The larger the solar zenith angle, the smaller the TEC enhancement. Even minor fast changes in TEC during this flare are revealed in the changing rate of temporal TEC variations in midlatitudes and low latitudes. These small globally synchronous disturbances of TEC were compared with the solar X-ray fluxes of this flare observed by satellites, and a close correlation between those small ionospheric disturbances and the hard X-ray flux fluctuations was found.