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GTE Corporation, formerly General Telephone & Electronics Corporation was the largest independent telephone company in the United States during the days of the Bell System.Originally founded in 1926 as Associated Telephone Utilities, it went bankrupt in 1933 during the Great Depression, and reorganized as General Telephone in 1934. In 1991, it acquired the third largest independent, Continental Telephone . They also owned Automatic Electric, a telephone equipment supplier similar in many ways to Western Electric, and Sylvania Lighting, the only non-communications-oriented company under GTE ownership. GTE provided local telephone service to a large number of areas of the U.S. through operating companies, much as American Telephone & Telegraph provided local telephone service through its 22 Bell Operating Companies.The company also acquired BBN Planet, one of the earliest Internet service providers, in 1997. That division became known as GTE Internetworking, and was later spun off into the independent company Genuity to satisfy Federal Communications Commission requirements regarding the GTE-Bell Atlantic merger that created Verizon.GTE operated in Canada via large interests in subsidiary companies such as BC TEL and Quebec-Téléphone. When foreign ownership restrictions on telecommunications companies were introduced, GTE's ownership was grandfathered. When BC Tel merged with Telus ) to create BCT.Telus, GTE's Canadian subsidiaries were merged into the new parent, making it the second-largest telecommunications carrier in Canada. As such, GTE's successor, Verizon Communications, was the only foreign telecommunications company with a greater than 20% interest in a Canadian carrier, until Verizon completely divested itself of its shares in 2004.In the Caribbean, CONTEL purchased several major stakes in the newly independent countries of the British West Indies .Prior to GTE's merger with Bell Atlantic, GTE also maintained an interactive television service joint-venture called GTE mainStreet as well as an interactive entertainment and video game publishing operation, GTE Interactive Media. Wikipedia.

Correlations of the type Nusselt-Rayleigh-Fourier are proposed to determine the convective exchanges that occur in transient regime in closed cavities of parallelogrammic section. They complement the correlations obtained in a previous work for steady state. The active vertical walls of these cavities are vertical, maintained isothermal and differentially heated, while the closing channel is adiabatic. This work covers a wide range of the Rayleigh number 1.84 × 105 ≤ Ra ≤ 1.70 × 109 and different angles of inclination ranging from -60° to 60°, enabling applications in several fields of engineering such as building, solar energy or power electronics. Correlations are obtained from numerical results based on the finite volume method and are validated by measurements. © 2012 Elsevier Ltd. All rights reserved. Source

Bairi A.,GTE
International Communications in Heat and Mass Transfer | Year: 2015

Qualification and quantification of the natural convective phenomena are examined in the case of a Quad Flat Non-lead (QFN32). This active electronic package is inclined with respect to the horizontal plane by an angle varying between 0° and 90° corresponding to the horizontal and vertical position respectively. It generates during its operation a constant volumetric heat flux leading to Rayleigh numbers varying in the range 1.31x107-1.01x108. The walls of the large air-filled cubic cavity containing this device are maintained isothermal. The temperature and velocity fields are presented for different combinations of the Rayleigh number and inclination angle. The convective heat transfer concerning the whole component exchange surface is determined for all the treated configurations. Correlations of Nusselt-Rayleigh type are proposed. They allow optimizing the thermal design of electronic assemblies used in various engineering domains. © 2015 Elsevier Ltd. Source

Bairi A.,GTE
International Communications in Heat and Mass Transfer | Year: 2015

The natural convective heat transfer coefficient detailed in this study deals with the five elements of a typical assembly used in electronics constituted by a Printed Circuit Board (PCB) on which a quad flat non-lead (QFN16) is welded. This active package can be placed in different positions on the board and generates during its actual functioning a power ranging between 0.1. W and 0.8. W. Many configurations of the assembly are considered, corresponding to seven inclination angles of the PCB varying between the horizontal and vertical positions. Correlations between the average convective heat transfer coefficient, the generated power and the PCB inclination angle are proposed for the five assembly parts. They allow to optimize the thermal control of electronic devices incorporating QFN16 packages, which are increasingly used in engineering. © 2015 Elsevier Ltd. Source

This work quantifies the natural convective heat transfer occurring in hemispherical air-filled cavities whose disk is inclined at an angle varying between 0° and 90°. This active hot disk as well as the dome are maintained isothermal at different temperatures. The numerical approach by means of the control volume method allows the examination of the dynamical phenomena that occurs in many configurations obtained by varying the temperature difference between the two active walls and the radius of the hemisphere. Convective heat transfer at the hot wall is represented by the average Nusselt number associated to Rayleigh numbers varying between 104 and 2.55×1012. By taking into account all the studied configurations, correlations between these two dimensionless numbers are established for the set of considered inclination angles. Comparisons with results from other studies for the case of horizontal cavity show a good agreement. The relationships presented here cover the laminar, transitional and turbulent heat transfer regimes. They complement previous studies with the condition of heat flux imposed on the disk. The wide range of Rayleigh numbers considered in this survey and its association with the large inclination angle range allow the application of the correlations to various engineering fields such as nuclear technology, solar energy, building, embarked electronics, architecture, safety or domotics. © 2014 Elsevier Ltd. Source

Bairi A.,GTE | Oztop H.F.,Firat University
International Communications in Heat and Mass Transfer | Year: 2014

In this study, relationships of Nusselt-Rayleigh-Fourier type are proposed for the case of air-filled hemispherical cavity whose dome is oriented downwards and maintained isothermal. Its disk is subjected to a constant heat flux and inclined at an angle varying between 90° (vertical position) and 180° (disk horizontal with dome oriented downwards). The numerical approach is performed in transient regime by means of the finite volume method for Rayleigh numbers in the range of 104-5×108. These results are confirmed at steady state by measurements done for some configurations in a previous study for the same Rayleigh and inclination ranges. Otherwise, they complete other surveys considering inclination angles varying between 0° (horizontal cavity with dome oriented upwards) and 90° (vertical cavity) for a wider range of Rayleigh numbers. The correlations allow thermal control of devices submitted to natural convection in hemispherical cavities during the time preceding the steady state after their switch on. © 2014 Elsevier Ltd. Source

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