Abstract: A process control system includes: a controller; at least one input and output module connected to the controller; and an allowable propagation delay value calculator in the controller, the allowable propagation delay value calculator being configured to calculate, based on the number of input and output modules connected to the controller, an allowable range for propagation delay time between the controller and the input and output module.

Abstract: A process control system includes: a controller; at least one input and output module connected to the controller; and an allowable propagation delay value calculator in the controller, the allowable propagation delay value calculator being configured to calculate, based on the number of input and output modules connected to the controller, an allowable range for propagation delay time between the controller and the input and output module.

Abstract: A plant control system includes: an engineering apparatus for defining change information so as to change definition information about the system; and a control apparatus for referring to the change information downloaded from the engineering apparatus to set an output value of a field device. The control apparatus includes a locking part for inhibiting setting of the output value of the field device.

Abstract: A redundant I/O module includes: a control I/O module that communicates with a controller and that comprises a first IOM setting information holding section for storing IOM setting information downloaded from a high-level apparatus, and a standby I/O module that communicates with the controller and that comprises a second IOM setting information holding section for storing IOM setting information downloaded from the high-level apparatus, wherein the controller includes: an IOM status generation section that detects a status of replacement of the standby I/O module; an IOM setting information acquisition section that makes an access to the first IOM setting information holding section of the control I/O module; an IOM setting information generation section that generates IOM setting information about the standby I/O module; and an IOM download section that downloads the generated IOM setting information into the second IOM setting information holding section of the standby I/O module.

Abstract: A redundant I/O module includes: a control I/O module that communicates with a controller and that comprises a first IOM setting information holding section for storing IOM setting information downloaded from a high-level apparatus, and a standby I/O module that communicates with the controller and that comprises a second IOM setting information holding section for storing IOM setting information downloaded from the high-level apparatus, wherein the controller includes: an IOM status generation section that detects a status of replacement of the standby I/O module; an IOM setting information acquisition section that makes an access to the first IOM setting information holding section of the control I/O module; an IOM setting information generation section that generates IOM setting information about the standby I/O module; and an IOM download section that downloads the generated IOM setting information into the second IOM setting information holding section of the standby I/O module.

Abstract: A plant control system includes: an engineering apparatus for defining change information so as to change definition information about the system; and a control apparatus for referring to the change information downloaded from the engineering apparatus to set an output value of a field device. The control apparatus includes a locking part for inhibiting setting of the output value of the field device.

Abstract: A diagnostic information management system having a field controller which sends diagnostic information indicating contents of a failure which occurs in the field, to a viewer via a network; and the viewer which displays the diagnostic information sent from the field controller, on a screen. The field controller has a storage section which stores diagnostic information that becomes master diagnostic information of the whole system. The viewer compares the diagnostic information held by itself with the master diagnostic information, and obtains the difference diagnostic information from the field controller side.

Abstract: A diagnostic information management system has: a field controller which sends diagnostic information indicating contents of a failure being occurred in a field, to a viewer via a network; and the viewer which displays the diagnostic information sent from the field controller, on a screen. The field controller has a storage section which stores diagnostic information that becomes master diagnostic information of the whole system. The viewer compares the diagnostic information held by itself with the master diagnostic information, and obtains the difference diagnostic information from the field controller side.

Abstract: 1,4-dihydropyridine derivatives and optically active 1,4-dihydropyridine derivatives with the following formula, having vasodilating activity based on calcium antagonism, and PAF antaognism, and methods of producing the same are disclosed: ##STR1## wherein (*) indicates a chiral center in the case of the optically active 1,4-dihydropyridine derivatives.

Abstract: 1,4-dihydropyridine derivatives and optically active 1,4-dihydropyridine derivatives with the following formula, having vasodilating activity based on calcium antagonism, and PAF antagonism, and methods of producing the same are disclosed: ##STR1## wherein (*) indicates a chiral center in the case of the optically active 1,4-dihydropyridine derivatives.

Abstract: 1,4-dihydropyridine derivatives and optically active 1,4-dihydropyridine derivatives with the following formula, having vasodilating activity based on calcium antagonism, and PAF antaognism, and methods of producing the same are disclosed: ##STR1## wherein (*) indicates a chiral center in the case of the optically active 1,4-dihydropyridine derivatives.

Abstract: 1,4-dihydropyridine derivatives and optically active 1,4-dihydropyridine derivatives with the following formula, having vasodilating activity based on calcium antagonism, and PAF antaognism, and methods of producing the same are disclosed: ##STR1## wherein (*) indicates a chiral center in the case of the optically active 1,4-dihydropyridine derivatives.

Abstract: 1,4-dihydropyridine derivatives and optically active 1,4-dihydropyridine derivatives with the following formula, having vasodilating activity based on calcium antagonism, and PAF antaognism, and methods of producing the same are disclosed: ##STR1## wherein (*) indicates a chiral center in the case of the optically active 1,4-dihydropyridine derivatives.