The load bearing capacity of railway masonry arch bridges

This paper deals with the way of calculating the load-bearing capacity of masonry arch railway bridges. It reviews the basic aspects of structural behaviour of these bridges, such as material non-linearity of masonry and interaction with the soil. Paper shows, how to include second order analysis in the calculation, because in some cases it might have non-negligible influence. It reminds the requirements of standards and shows, how to calculate the load-bearing capacity in accordance with these requirements with influence of mentioned non-linearities

The load bearing capacity of railway masonry arch bridges

This paper deals with the way of calculating the load-bearing capacity of masonry arch railway bridges. It reviews the basic aspects of structural behaviour of these bridges, such as material non-linearity of masonry and interaction with the soil. Paper shows, how to include second order analysis in the calculation, because in some cases it might have non-negligible influence. It reminds the requirements of standards and shows, how to calculate the load-bearing capacity in accordance with these requirements with influence of mentioned non-linearities

Engineering calculations for the Delta S method of solving the orbital allotment problem

The method of calculating single-entry separation requirements for pairs of satellites is extended to include the interference on the top link as well as on the down link. Several heuristic models for analyzing the effects of shaped-beam antenna designs on required satellite separations are introduced and demonstrated with gain contour plots. The calculation of aggregate interference is extended to include the effects of up-link interference. The relationship between the single-entry C/I requirements, used in determining satellite separation constraints for various optimization procedures, and the aggregate C/I values of the resulting solutions is discussed

An automated program for reinforcement requirements for openings in cylindrical pressure vessels

An automated interactive program for calculating the reinforcement requirements for openings in cylindrical pressure vessels subjected to internal pressure is described. The program is written for an electronic desk top calculator. The program calculates the required area of reinforcement for a given opening and compares this value with the area of reinforcement provided by a proposed design. All program steps, operating instructions, and example problems with input and sample output are documented

Specifying and calibrating instrumentations for wideband electronic power measurements

The wideband electric power measurement related topics of electronic wattmeter calibration and specification are discussed. Tested calibration techniques are described in detail. Analytical methods used to determine the bandwidth requirements of instrumentation for switching circuit waveforms are presented and illustrated with examples from electric vehicle type applications. Analog multiplier wattmeters, digital wattmeters and calculating digital oscilloscopes are compared. The instrumentation characteristics which are critical to accurate wideband power measurement are described

Computational aerodynamics and artificial intelligence

The general principles of artificial intelligence are reviewed and speculations are made concerning how knowledge based systems can accelerate the process of acquiring new knowledge in aerodynamics, how computational fluid dynamics may use expert systems, and how expert systems may speed the design and development process. In addition, the anatomy of an idealized expert system called AERODYNAMICIST is discussed. Resource requirements for using artificial intelligence in computational fluid dynamics and aerodynamics are examined. Three main conclusions are presented. First, there are two related aspects of computational aerodynamics: reasoning and calculating. Second, a substantial portion of reasoning can be achieved with artificial intelligence. It offers the opportunity of using computers as reasoning machines to set the stage for efficient calculating. Third, expert systems are likely to be new assets of institutions involved in aeronautics for various tasks of computational aerodynamics