Abstract: There is provided a vehicle driving support device including: a change amount calculating part 10 that calculates a first correlation value correlated to a change amount of acceleration of a vehicle; a jerk calculating part 11 that calculates a second correlation value correlated to a jerk of the vehicle; and an operation state determining part 13 that determines a driving operation state of the vehicle from a first correlation value calculated by a change amount calculating part 10, and a second correlation value calculated by a jerk calculating part 11, in accordance with a determination reference previously set from a ratio of a kinetic energy of a mass point to the change amount of the acceleration of the vehicle at an end point of change when the acceleration of the vehicle is changed, calculated using a vibration model showing a movement of the mass point in a passenger compartment.

Abstract: There is provided a vehicle driving support device including: a change amount calculating part 10 that calculates a first correlation value correlated to a change amount of acceleration of a vehicle; a jerk calculating part 11 that calculates a second correlation value correlated to a jerk of the vehicle; and an operation state determining part 13 that determines a driving operation state of the vehicle from a first correlation value calculated by a change amount calculating part 10, and a second correlation value calculated by a jerk calculating part 11, in accordance with a determination reference previously set from a ratio of a kinetic energy of a mass point to the change amount of the acceleration of the vehicle at an end point of change when the acceleration of the vehicle is changed, calculated using a vibration model showing a movement of the mass point in a passenger compartment.

Abstract: A direct injection diesel engine includes a cylinder head which is formed, for each cylinder, with a plurality of intake ports. At least one of the intake ports has an approximately straight throat extending tangentially to the cylinder and opening into a combustion chamber at upper reaches of swirling. Another of the intake ports has a throat opening into the combustion chamber at lower reaches of swirling. A glow plug extends downward from one side of the cylinder head, at which the intake ports open, toward a location between the other intake port. An exhaust port extends from another side of the cylinder head and opens into the combustion chamber.

Abstract: An intake port of an engine cylinder is directed so as to introduce intake air flow into a combustion chamber in a desired direction. The intake port has a throat portion, extending upstream from a valve port and configured so as to meet the valve port at a given angle, and a transitional throat portion with a small radius of curvature between the throat portion and the valve port.