An image forming apparatus comprises an image forming unit; a sensor that measures a measurement image; and a controller. The controller controls the image forming condition based on a measurement result of measuring a first measurement image; acquires information having a correlation to density variation of images to be formed by the image forming unit; controls the image forming condition based on the information; determines a first value regarding a density of an image to be formed, based on a measurement result of measuring a second measurement image; determines a second value regarding a density of the image to be formed by the image forming unit, based on the information; and controls a timing at which the image forming unit next forms the first measurement image, based on the first value and the second value.

A method, a system, and a non-transitory computer readable recording medium are disclosed for a first printer connected to a second printer to perform color calibration for the second printer, wherein the second printer does not have a sensor, the first printer including a sensor which measures a media, which has been printed by the second printer and is being fed on a media path of the first printer. The method includes (a) determining the timing to instruct the second printer to print a first measurement chart; (b) instructing, at the timing determined at step (a), the second printer to print the first measurement chart; (c) measuring, by the sensor, the first measurement chart which has been printed by the second printer; and (d) outputting information corresponding to a result measured at step (c).

An electronic device that checks a connected state of a signal line is provided. The electronic device includes a controller configured to transmit a check signal and at least one module configured to include a closed loop and receive the check signal. When the controller receives the check signal through the closed loop, the controller determines that the at least one module is connected to the controller.

Methods and apparatus for predicting colorant usage by printing devices are provided. A prediction server can receive a request to predict colorant usage for a first printing device. The prediction server can determine first plurality of functions to predict colorant usage for the first printing device. The first plurality of functions can include at least one linear function and at least one non-linear function. The first plurality of functions can be based on colorant-usage rates indicating historical rates of change in colorant used by the first printing device. The prediction server can determine a prediction of colorant usage for the first printing device using the first plurality of functions. The prediction server can provide an output involving the prediction of colorant usage for the first printing device, where the prediction of colorant usage can include a confidence interval related to the prediction.

An image reading apparatus includes: an operation unit; a setting unit configured to set one of a plurality of operation modes, in which different processing is executed for a document, in accordance with an operation content of the operation unit; a reading unit configured to read the document in response to a reading execution request from the operation unit; and a control unit configured to control the reading unit whether or not to execute a reading preparation operation before the reading execution request is made depending on the set operation modes set by the setting unit.

An inkjet image forming apparatus includes a transferer and a hardware processor. The transferer transfers, onto a recording medium, ink that is ejected from an inkjet head and is borne on a transfer member. The hardware processor performs control for reducing transferability of the ink in a case where the ink borne on the transfer member is not-to-be-transferred ink, compared with a case where the ink is to-be-transferred ink.

A sound diagnosis system includes: a setting unit configured to set a threshold for each of a plurality of time sections, based on a sound wave level in each of the plurality of time sections of a plurality of first sound data classified in a first group; and a determination unit configured to determine whether or not an abnormal sound is generated by calculating a comparison value for each of the plurality of time sections based on a sound wave level in each of the plurality of time sections of one or more second sound data classified in the first group, and comparing the comparison value for each of the plurality of time sections with the threshold value of the corresponding time section of the first group, the threshold value being set by the setting unit.

The image forming apparatus includes the power supply board for generating a +24V power supply voltage and a driver board for driving a load for forming an image, and an engine control board for controlling an operation of a driver board. The driver board includes a fuse which receives the 24V power supply voltage supplied from the power supply board. The driver board drives the load by +24V_FU1 voltage output from the fuse. The engine control board identifies, when an abnormality occurs in an operation of the load, a board that is a cause of the abnormality according to a voltage value of the +24V_FU1 voltage and the voltage value of the power supply voltage.

An image forming apparatus comprises an image forming unit; a sensor that measures a measurement image; and a controller. The controller controls the image forming condition based on a measurement result of measuring a first measurement image; acquires information having a correlation to density variation of images to be formed by the image forming unit; controls the image forming condition based on the information; determines a first value regarding a density of an image to be formed, based on a measurement result of measuring a second measurement image; determines a second value regarding a density of the image to be formed by the image forming unit, based on the information; and controls a timing at which the image forming unit next forms the first measurement image, based on the first value and the second value.

An image forming apparatus includes: an image former that executes image forming processing; a primary controller; a secondary controller that controls the image former; a sensor that detects a state of at least a unit of the image forming apparatus and transmits sensor data indicating the state to the secondary controller; a first transmission path for duplex communication between the primary and secondary controllers; and a second transmission path. The secondary controller: generates, from the sensor data, diagnostic data for failure diagnostics or life prediction, transmits data other than the diagnostic data to the primary controller via the first transmission path and transmits the diagnostic data to the diagnostic server via the second transmission path, or transmits data other than the sensor data to the primary controller via the first transmission path and transmits the sensor data to the diagnostic server via the second transmission path.