摘要:

This paper reports a theoretical study of the transient thermal stress distributions of a layered slab which is composed of two different materials. The layered slab is heated by a moving line heat source on its upper surface and cooled convectively on the lower surface. In order to solve the initial and boundary value problem, a general hybrid Laplace transform/finite element method is utilized. Finally, a numerical procedure, the Fourier series technique, is used to obtain the inversion of the Laplace transform. The effect of the number of mesh elements in theX‐direction is also investigated to verify the accuracy and convergence of the finite element method. In addition, a typical result is compared with the analytic solution. The numerical results of the transient temperature and thermal stress distribution of the layered slab are presented to demonstrate the effect of the physical properties.

ISSN:0253-3839    

DOI:10.1080/02533839.1990.9677276

出版商:Taylor & Francis Group    

年代:1990

数据来源: Taylor

摘要:

The stabilization of an interconnected system is considered. Based on the Lyapunov stability theorem, two simple stabilization criteria for interconnected systems are derived using different Lyapunov functions. These main results are expressed by the measurement of the system matrices directly, without solving the Lyapunov equations. The two stabilization criteria are also compared.

ISSN:0253-3839    

DOI:10.1080/02533839.1990.9677277

出版商:Taylor & Francis Group    

年代:1990

数据来源: Taylor

摘要:

In this report, several methods have been provided to investigate the possibility of a long‐term sealed‐off operation of a CW transversely‐excited (TE) CO2laser. These methods include the additions of molecular 3A sieve, CO gas, auxiliary discharge, and catalysts. Variations of gas composition, discharge voltage, and laser power under different conditions have been analyzed. SnO2coating devices and monolithic catalysts have been introduced for the first time in a CW TE CO2laser. With an appropriate amount of these catalysts, sealed‐off operation with an output level at 550W for more than 110 Hours of discharge time was achieved.

ISSN:0253-3839    

DOI:10.1080/02533839.1990.9677278

出版商:Taylor & Francis Group    

年代:1990

数据来源: Taylor

ISSN:0253-3839    

DOI:10.1080/02533839.1990.9677265

出版商:Taylor & Francis Group    

年代:1990

数据来源: Taylor