Abstract: An analysis device constructs an analytical model with a circuit board and a medium, and applies a concentrated load grouping composed of concentrated loads to the circuit board. In this case, the concentrated loads are established such that the sum of the respective vectors is zero, and such that the torque is zero with respect to the center of gravity. The analysis device applies a finite element method to the analytical model to figure out the vibration of the circuit board, which is caused when the concentrated loads vibrate with a constant period. The change in the pressure of the medium is computed from the vibration of the circuit board, and the change in the pressure is converted to a sound pressure.

Abstract: This disclosure provides a signal transmission communication unit and a coupler that can occupy a small area and have a reduced thickness. The signal transmission communication unit includes a base component including a signal transmission line and a ground electrode, a coupling planar conductor parallel to the base component and having a planar shape, an inductor circuit connected between the coupling planar conductor and the signal transmission line, and an LC-series circuits between part of the coupling planar conductor and the ground electrode and including a capacitor and an inductor connected in series. The inductor circuit is provided between the coupling planar conductor and the base component, and the LC-series connected circuit is provided between the coupling planar conductor and the base component.

Abstract: An air-fuel ratio control system for an internal combustion engine has an air-fuel ratio sensor arranged in the exhaust system of the engine, for detecting the air-fuel ratio of exhaust gases emitted from the engine, and various engine operating parameter sensors for detecting operating conditions of the engine. An ECU controls the air-fuel ratio of an air-fuel mixture to be supplied to the engine to a desired air-fuel ratio in a feedback manner responsive to an output from the air-fuel ratio sensor. A first learned value for correcting the desired air-fuel ratio is calculated based on the feedback control when the engine is detected to be in a first predetermined operating condition, and a second learned value for correcting the desired air-fuel ratio when the engine is detected to be in a second predetermined engine operating condition. The air-fuel ratio of the air-fuel mixture is controlled to a value leaner than a stoichiometric value, by using the first learned value.

Abstract: A robot system for exterminating termites living in wood structural members under the floor of an architectural structure. The robot system comprises a robot including an onboard computer which is electrically connected through radio communication with a host computer located outside the robot. The robot includes a main body and is equipped with a locomotive mechanism including a pair of caterpillars located on the opposite sides of the main body. The caterpillars are driven by driving motors mounted on the robot and can be independently operated. The robot includes a mechanism for controlling the vertical positions of various sections of the main body relative to the caterpillars. A nozzle mechanism for spraying chemical or insecticide and a CCD camera are mounted on the main body. The onboard computer and host computer are operatively associated with each other to control the driving motors, the vertical position controlling mechanism, the nozzle mechanism and the CCD camera.

Abstract: An air-fuel ratio control method for an internal combustion engine. The air-fuel ratio of an air-fuel mixture supplied to the engine is feedback-controlled to a desired air-fuel ratio dependent on operating conditions of the engine. When a transmission is being shifted or before a predetermined time period elapses after the shifting, the desired air-fuel ratio is held at a value assumed immediately before the shifting of the transmission. In another form of the invention, when the transmission is being shifted, or when the operating characteristics of at least one set of a set of intake valves and a set of exhaust valves have been not changed before the predetermined time period elapses after the shifting of the transmission, the desired air-fuel ratio is held at a value assumed before the shifting of the transmission.

Abstract: An air-fuel ratio control system for an internal combustion engine, which detects the actual air-fuel ratio of a mixture supplied to the engine, detects operating conditions of the engine, calculates a desired air-fuel ratio based on the detected operating conditions of the engine, and calculates an air-fuel ratio correction value applied for feedback-controlling the actual air-fuel ratio to the calculated desired air-fuel ratio. A change rate at which the air-fuel ratio correction value is to be changed, is set such that when a change has occurred in the operating mode of the engine, the change rate is set to and held at a smaller value than a value assumed when no change has occurred in the operating mode, over a predetermined time period from the time the change occurred.

Abstract: An air-fuel ratio control method for an internal combustion engine. The air-fuel ratio of an air-fuel mixture supplied to the engine is feedback-controlled to a desired air-fuel ratio depending on operating conditions of the engine in response to output from an exhaust gas ingredient concentration sensor. The desired air-fuel ratio is settable to a value leaner than a stoichiometric air-fuel ratio when the temperature of the engine is above a predetermined reference value. The method comprises the steps of detecting a reduction ratio to which the transmission has been set, and changing the predetermined reference value of the temperature of the engine depending on the detected reduction ratio. The predetermined reference value of the temperature of the engine is set to a lower value as the reduction ratio of the transmission is smaller.

Abstract: An air-fuel ratio control method for an internal combustion engine, in which the air-fuel ratio of a mixture supplied to the engine is feedback-controlled to a desired air-fuel ratio in response to output from an exhaust gas ingredient concentration sensor. When the engine is in a predetermined accelerating condition, fuel supply to the engine is increased. The rate of correction of the air-fuel ratio of the mixture by the feedback control is set to a smaller value when the engine is in the predetermined accelerating condition, than values to be set when the engine is in other operating conditions.

Abstract: An air-fuel ratio control method for an internal combustion engine. The air-fuel ratio of an air-fuel mixture supplied to the engine is feedback-controlled to a desired air-fuel ratio in response to output from an exhaust gas ingredient concentration sensor. When the desired air-fuel ratio is to be changed in a leaning direction from a value equal to or leaner than a stoichiometric air-fuel ratio, it is changed at a larger rate until it reaches a predetermined value than after it has reached the predetermined value. The predetermined value is set to a value slightly leaner than an air-fuel ratio at which the amount of emission of NO.sub.X increases.

Abstract: An air-fuel ratio control method for an internal combustion engine, in which the air-fuel ratio of a mixture supplied to the engine is feedback-controlled to a desired air-fuel ratio in response to output from an exhaust gas ingredient concentration sensor. When the engine is in a predetermined decelerating condition, fuel supply to the engine is cut off. The rate of correction of the air-fuel ratio of the mixture by the feedback control is set to a larger value before a predetermined time period elapses after the engine shifted from the predetermined decelerating condition to another operating condition, than values to be set after the predetermined time period has elapsed.