Abstract: A delay circuit in accordance with the present invention includes: a first I2L inverter and a second I2L inverter connected in cascade with each other; and a capacitor interposed between a ground and a connecting point of the first and second inverters, wherein: the delay circuit further includes a current adjusting circuit having at least one third I2L inverter with a plurality of output terminals at least one of which is connected to an input terminal of the third I2L inverter; and the current adjusting circuit is connected to adjust a charge current of the capacitor. The configuration provides a delay circuit of simple circuit structure that accounts for a small area in an integrated circuit and that is capable of introducing any given delay and also provides a ring oscillator incorporating the delay circuit.

Abstract: A delay circuit in accordance with the present invention includes: a first I2L inverter and a second I2L inverter connected in cascade with each other; and a capacitor interposed between a ground and a connecting point of the first and second inverters, wherein: the delay circuit further includes a current adjusting circuit having at least one third I2L inverter with a plurality of output terminals at least one of which is connected to an input terminal of the third I2L inverter; and the current adjusting circuit is connected to adjust a charge current of the capacitor. The configuration provides a delay circuit of simple circuit structure that accounts for a small area in an integrated circuit and that is capable of introducing any given delay and also provides a ring oscillator incorporating the delay circuit.

Abstract: A method of operating a blast furnace enables substantial improvement of gas permeability and liquid permeability for stable operation of the blast furnace, involves packing the core section with solid high strength, carbonaceous blocks prior to ignition of the furnace. The carbon blocks resist wearing and high temperature reaction over very long periods of operating time, greatly stabilizing the furnace. Because of the improved stabilization, gas permeability and liquid permeability, a low grade solid reducing agent can be substituted for a quantity of the high quality coke normally used for operating the blast furnace and furthermore enables injection of pulverized coal at a rate of at least 200 Kg/ton-pig.