Engineering and Technology Journal

Large increases in the storage capacities of computers will be needed in the near future. Amongst other technologies, the bubble memory has been suggested as a solid replacement for the electro-mechanical disc. This paper outlines the fundamental basis of operation and the organization of a magnetic bubble memory. The physical implementation of the functions of storage, generation, detection and transfer of the domain are described in order to realize the bubble memory.

The paper investigates the relationship between the two standard methods of design that are used for dimensioning reinforced concrete rectangular sections subject to simple bending, namely, the flexural strength design method, and the working stress design method. It makes it possible (within certain limitations) to use either method to obtain identical results. It establishes the stress factors to be used in working stress design that would give results equivalent to a specified set of load factors that are adopted by the flexural strength design method, and vice versa.

The porosity formed during interdiffusion in OFHC Cu/Ni diffusion couples, and in OFHC Cu discs and cylinders due to hydrogen have been studied. Different Volumes of porosity and dimensional changes were obtained after diffusion annealing in Vacuum and in 1 atm argon gas under similar conditions. porosity introduced previously in OFHC Cu prior to welding to Ni affected the subsequent porosity during Diffusion annealing. Pretraining of specimens showed extensive porosity but with reduced sizes. These observations can create problems in many engineering areas such as coating of materials, composite materials and where fine tolerances are required.   

In a previous work, the optimum design of X charts when there is a single assignable cause occurring randomly was studied. The present article extends the study to allow for the occurrence of several assignable causes. 14 independent variables are encountered in the model. The optimum values of the size and Frequency of sampling and the position of control limits are to be seeked.