Abstract: Each print job received from a client computer 30 is divided into minimum printing units as divisional jobs, which are stored in a job folder 23b. When either of an upper spooler 23d and a lower spooler 23e has any vacancy for next allocation, one divisional job is allocated to a printer corresponding to the spooler having the vacancy. The name of the printer that has received allocation of the divisional job is written into the job folder 23b. When any allocated divisional job having an identical image file name and an identical customer ID with those of a current object divisional job is present in the job folder 23b, the current object divisional job is allocated to the printer, to which the allocated divisional job has been allocated. This arrangement allocates multiple divisional jobs for printing an identical image demanded from an identical customer to the same printer, thus ensuring substantially equal quality of resulting printed images.

Abstract: Various high quality microwave dielectric composite compositions are prepared by replacing a part of Ba, La or Ti with another element in a dielectric material represented by BanLa4Ti3+nO12+3n. A first embodiment thereof comprises a ceramic composition represented by (Ba1−xAx)nLa4Ti3+nO12+3n, wherein A is an alkaline earth metal element except Ba, and 0.5<n<5 and 0<x<0.5, which is a composite composition being homologous as the former dielectric material and having a chemical formula obtained by replacing a part of Ba with an alkaline earth metal element except Ba. Similarly, a part of La and a part of Ti can be replaced with a rare earth element except La and an element except Ti, respectively.

Abstract: A first inventive microwave dielectric composition comprises a ceramic composition represented by AnR4Ti3+nO12+3n, where a is an alkaline earth metal element, R is a rare earth element and characterized in that a case satisfying A=Ba and a case of R=La is excluded and the compositional ratio n=1,2 or 4.