A damage estimation device includes an acquisition unit that acquires a temperature change amount in a period during which an inflow air temperature rises and a period length, a distortion amount derivation unit that derives a distortion amount of a cooling device in the above period, based on the temperature change amount, and a damage value derivation unit that derives an accumulated damage value by integrating a value depending on the distortion amount. When the period length is shorter than a period length determination value, the distortion amount derivation unit derives a larger value as the distortion amount than when the period length is equal to or longer than the period length determination value.

An agricultural work vehicle according to an aspect of the invention that can monitor a state of the agricultural work vehicle when the agricultural work vehicle performs agricultural work using a working machine which is attached thereto includes: a vehicle body; a working machine that is attached to the front or rear of the vehicle body and performs agricultural work; an engine that generates a driving force for movement of the vehicle body and work of the working machine; and a monitoring device that determines at least one of whether there is an abnormality in a temperature of a coolant for cooling the engine, whether there is an abnormality in a pressure of an engine oil supplied to the engine, and whether there is an abnormality in the engine when the working machine performs work using the driving force.

A method for measuring vibration acceleration in three mutually orthogonal planes via vibration sensors. Vibration accelerations are measured at the monitoring points on an operational and knowingly fault-free diesel generator, and then vibration accelerations are measured at the monitoring points of a diesel generator in the course of its operation with prescribed intervals. Temperature and intensity of an ultrasonic signal are additionally measured at the same monitoring points, and the root mean square values of the ultrasonic signal intensity, temperature and vibration acceleration are determined. The measured vibration acceleration values are used to calculate the root mean square values of vibration velocity and vibratory displacement, the distances between clusters of preceding measurements are determined, and a conclusion on the operating state of the diesel generator is made. The method promotes timely detection of any operating defects through periodic measurements and comparison of calculations.

An ion current detection circuit is for detecting an ion current flowing through a spark plug for an internal combustion engine. A detection terminal is to be electrically connected to the spark plug. A reference potential is to be supplied to a reference terminal. At least one protection diode is provided between the detection terminal and the reference terminal. A current detection unit causes a detection current to flow between the detection terminal and the at least one protection diode. A current compensation unit causes a compensation current to flow between the detection terminal and the at least one protection diode.

A cylinder liner for an internal combustion engine is formed of cylindrical liner body having an interior cavity with a cylindrical inner surface, a sensor embedded in the cylindrical liner body and being configured for sensing a physical condition on the cylindrical inner surface, and a transmitter connected to the cylindrical liner body at a position remote from the sensor. A connecting wire connects the transmitter to the sensor, and is embedded in in the cylindrical liner body. The sensor is located in an upper portion of the cylindrical liner body and the transmitter is located directly below the sensor, such that the wire runs vertically. The transmitter can send information obtained by the sensor to a remote processor for calculating various operating states of the liner.

A rapid compression machine (RCM) employs an electrical drive to move a piston disposed within a chamber housing. The electrical drive converts electrical power into linear motion of the piston, for example, to compress contents in a reaction chamber defined by the chamber housing and the piston. The temperature and pressure changes induced by the compression can cause reaction of contents within the chamber, for example, autoignition of the contents. The RCM can thus be used to study chemical kinetics. In some embodiments, the electrical drive can also rapidly move the piston in reverse to expand a volume of the reaction chamber, for example, to quench the compression-induced reaction therein. In such embodiments, the RCM may be considered a rapid compression-expansion machine (RCEM) and can be used for speciation studies.

An emissions test system includes an emissions analyzer, a contamination index module, and a diagnostic module. The emissions analyzer is configured to determine a concentration of an emission in a sample of exhaust gas from an engine. The contamination index module is configured to determine a contamination index based on at least two of a flow rate of the exhaust gas sample, the concentration of the emission in the exhaust gas sample, an operating duration of the emissions test system, a pressure of the exhaust gas, and a temperature of the exhaust gas. The diagnostic module is configured to identify potential contamination of at least one of the emissions test system and a component in the emissions test system based on the contamination index.

A sensor failure diagnostic apparatus includes a first estimation unit to estimate a mixing ratio of each type of a molecular structure included in a fuel, based on combustion parameters when a combustion of an internal combustion engine is executed in different combustion conditions, among the combustion parameters sensed by a combustion sensor, a second estimation unit to estimate the mixing ratio, based on characteristic parameters sensed by a characteristic sensor, a combustion sensor diagnostic unit to determine whether a failure of the combustion sensor exists, based on a sensed value of the combustion sensor when the combustion is not executed, and a characteristic sensor diagnostic unit to determine whether a failure of the characteristic sensor exists, by comparing the mixing ratio estimated by the first estimation unit with the mixing ratio estimated by the second estimation unit when the combustion sensor diagnostic unit determines the combustion sensor is normal.

When an engine rotation speed is lower than a reference rotation speed, first failure determination in which failure of a flow rate control valve is determined based on a pressure change of cooling water detected by a pressure sensor is executed, when a valve closing instruction to switch the flow rate control valve from an opened state to a closed state is output from a valve control device; and when an engine rotation speed is equal to or higher than the reference rotation speed, second failure determination in which failure of the flow rate control valve is determined based on a pressure change of cooling water detected by a pressure sensor is executed, when a valve opening instruction to switch the flow rate control valve from a closed state to an opened state is output from the valve control device.

A cylinder liner for an internal combustion engine is formed of cylindrical liner body having an interior cavity with a cylindrical inner surface, a sensor embedded in the cylindrical liner body and being configured for sensing a physical condition on the cylindrical inner surface, and a transmitter connected to the cylindrical liner body at a position remote from the sensor. A connecting wire connects the transmitter to the sensor, and is embedded in in the cylindrical liner body. The sensor is located in an upper portion of the cylindrical liner body and the transmitter is located directly below the sensor, such that the wire runs vertically. The transmitter can send information obtained by the sensor to a remote processor for calculating various operating states of the liner.