Abstract: A job step parallel execution control system in a computer system has a job control statement which can designate whether a job step is to be executed by a specifically designated host computer or by an arbitrarily selected host computer, whether parallel execution of the job step while an other job step in the same job is in execution, and/or whether the job is to be continued, to be forcedly terminated or to be terminated after termination of the other job step of the job currently in execution, upon commanding execution of the job step. Upon execution of the job, the job control statement is sequentially decoded to efficiently control parallel execution and termination of execution of the job step.

Abstract: A molten steel pouring nozzle which comprises: a nozzle body comprising an alumina-graphite refractory, having, along the axis thereof, a bore through which molten steel flows; and an outer refractory layer arranged on an outside portion of the nozzle body so as to be integral with the nozzle body and to be flush with an outer surface thereof, the outer refractory layer being arranged on a portion of the outside portion of the nozzle body, which portion is in contact, when a lower portion of the molten steel pouring nozzle is immersed into molten steel, with the open air without being immersed into the molten steel, and the outer refractory layer consisting essentially of:______________________________________ alumina (Al.sub.2 O.sub.3) from 40 to 75 wt. %, carbon (C) from 10 to 30 wt. %, silica (SiO.sub.2) from 1 to 30 wt. %, silicon carbide (SiC) from 1 to 20 wt. %, and low-melting glass from 1 to 10 wt. %.

Abstract: A pressure-casting machine that contains a delivery system, which comprises: a molten metal pouring pipe made of a refractory, having a length of at least 4 m and an outside diameter of at least 350 mm, and arranged such that an upper end thereof is attached substantially vertically from below to an opening in a bottom wall of a mold for a pressure-casting machine, and a lower end thereof extends through a lid of a closed vessel arranged below the mold and is immersed into molten metal received in a ladle arranged in the closed vessel. The molten metal pouring pipe comprises at least two pipe sections connected to each other in series and in a liquid-tight manner by means of a threaded joint, tapered surfaces provided with screw threads of which have an inclination angle within a range of from 2.0.degree. to 15.0.degree. relative to the center axis of the molten metal pouring pipe.