Bite and unconfirmed failures

Electronic BITE is poor at identifying hardware failure and in present design approaches tends to create the reviled ‘unconfirmed failure’. A different approach to BITE and unconfirmed failure could improve both operational performance and the cost of maintenance.     

An infestation by Araecerus fasciculatus (Degeer) (Coleoptera: Anthribidae) and Decadarchis minuscula (Walsingham) (Lepidoptera: Tineidae) on stored fresh yam tubers in South-East Nigeria

In the course of storage trials in South-East Nigeria, four species of yam became infested with Araecerus fasciculatus (Degeer) and Decadarchis minuscula (Walsingham). Infestation was first observed in early February on Dioscorea dumetorum (Kunth) Pax. but quickly spread to D. rotundata Poir. and thence to D. alata L. and D. cayenensis Lam. The order of species attacked was probably related to their rate of drying. Both insects occurred together and attacked mainly the cut and damaged areas of the stored tubers.     

Avalanche multiplication characteristics ofAl0.8Ga0.2As diodes

The avalanche multiplication characteristics of Al_0.8Ga _0.2As have been investigated in a series of p-i-n and n-i-p diodes with i-region widths, w, varying from 1 μm to 0.025 μm. The electron ionization coefficient, α, is found to be consistently higher than the hole ionization coefficient, β, over the entire range of electric fields investigated. By contrast with Al_xGa _1-xAs (x⩽0.6) a significant difference between the electron and hole initiated multiplication characteristics of very thin Al_0.8Ga_0.2As diodes (w=0.025 μm) was observed. Dead space effects in the diodes with w⩽0.1 μm were found to reduce the multiplication at low bias below the values predicted from bulk ionization coefficients. Effective α and β that are independent of w have been deduced from measurements and are able to reproduce accurately the multiplication characteristics of diodes with w⩾0.1 μm and breakdown voltages of all diodes with good accuracy. By performing a simple correction for the dead space, the multiplication characteristics of even thinner diodes were also predicted with reasonable accuracy