Abstract: A parameter estimation device for estimating parameters relating to input and output of a control object by using a neural network, including control domain division means for selecting at least one parameter having strong correlation with non-linearity amongst input-output characteristics of the control object, as a parameter of a premise part of fuzzy operation, and dividing a control domain of the control object into a plurality of small domains by fuzzy estimation based on the parameter of the premise part; and estimation means for estimating dynamic behavior of the control object by using, as a consequent part of the fuzzy operation, a neural network which receives a parameter indicating the operation state of each of the small domain into which the control domain is divided, so that the output from the neural network can be checked in advance.

Abstract: A parameter estimation device for estimating parameters relating to input and output of a control object by using a neural network, comprises control domain division means for selecting at least one parameter which has strong correlation with non-linearity amongst input-output characteristics of the control object, as a parameter of a premise part of fuzzy operation, and dividing a control domain of the control object into a plurality of small domains by fuzzy estimation based on the parameter of the premise part; and estimation means for estimating dynamic behavior of the control object by using, as a consequent part of the fuzzy operation, a neural network which receives a parameter indicating the operation state of each of the small domains into which the control domain is divided.

Abstract: The present invention relates to a limiting-current type hydrocarbon sensor comprising a solid-electrolytic layer made of a Ba—Ce-based oxide, and provides a sensor capable of stably detecting hydrocarbon at high sensitivity, regardless of the concentration of oxygen in an atmosphere. A material mainly containing Al is used for at least one of two electrodes on the solid-electrolytic layer made of a Ba—Ce-based oxide to block oxygen at the electrode, i.e. cathode, whereby a hydrocarbon sensor being stable, high in sensitivity, compact, easy to use and low in cost can be provided. Furthermore, the other electrode, anode, of the limiting-current type hydrocarbon sensor is made of a material mainly containing Ag.

Abstract: A control device for controlling an air-to-fuel ratio when fuel is injected in an internal combustion engine, comprises: a state detecting unit for detecting parameters representing operating states of the internal combustion engine; a counting unit for counting the number of times of explosion in a cylinder just after the engine starts; and a unit for estimating an air-to-fuel ratio just after the engine starts from the operating state parameters and the number of times of explosion.

Abstract: The present invention relates to a skutterudite thermoelectric material for directly converting heat generated by the Seebeck effect into electricity, and provides a method of producing a Co—Sb-based filled-skutterudite sintered material having a lower thermal conductivity and thereby having a higher figure of merit. The crystal grains of a Sb-containing skutterudite compound and a metal oxide dispersed in the crystal grain boundaries are sintered to obtain the skutterudite thermoelectric sintered material. The metal oxide prevents growth of grains in the process of sintering, whereby the skutterudite compound is finely pulverized to have an average crystal grain size of 20 &mgr;m or less. As a result, the areas at the boundaries of the fine crystal grains are increased, phonon scattering is enhanced, the thermal conductivity is decreased, and the figure of merit is increased. The metal oxide is an oxide of a rare earth metal.

Abstract: An output parameter estimation apparatus for estimating an output parameter from an input data set that is composed of a plurality of input parameters and that is obtained whenever sampling time series input data. In this output parameter estimation apparatus, a fuzzy inference rule is used to calculate a fitness degree of the input data set in one of a plurality of fields included in a space that is formed using at least one input parameter. According to the calculated fitness degree, introduction routes through which the input data set is to be inputted into a neural network are selected. The neural network is set in a connection condition corresponding to the field to which the input data set belongs, the connection condition having been determined in advance as a result of learning process. With this connection condition, the neural network estimates the output parameter from the input data set inputted through the selected introduction routes.

Abstract: The present invention relates to a thermoelectric material containing CoSb.sub.3 compound for converting heat to electricity, and provides a p-type thermoelectric material of CoSb.sub.3 having a high power factor by achieving high Seebeck coefficient consistently with high electric conductivity in a material of CoSb.sub.3 system without causing increase in heat conductivity. By sintering Co.sub.0.07 Pt.sub.0.03 Sb.sub.3 alloy powder using the spark plasma sintering technique, the material is densified, while growth of grains is restricted, so that a higher electric conductivity is achieved with a heat conductivity maintained in a low level, and the figure of merit as a heat-transfer material is improved. Also, by providing such heat insulating layer as an oxide intermediately in a grain boundary of a compound of CoSb.sub.3 in a sintered body, the heat conductivity is reduced. Further, the Seebeck coefficient is increased by adding a rare earth metal to the thermoelectric material of CoSb.sub.

Abstract: An air/fuel ratio control apparatus for executing auxiliary control of an air/fuel ratio by compensating an injected fuel amount set by a control system for maintaining the air/fuel ratio at a preset value. The air/fuel ratio control apparatus includes a state detecting unit for detecting a plurality of physical values which can be measured at low temperature and which show a state of an engine, an air/fuel ratio estimating unit for receiving a plurality of physical values detected by the state detecting means as input parameters and for estimating the air/fuel ratio using a neural network, and a compensatory fuel amount calculating unit for calculating a compensatory fuel amount for the injected fuel amount from the estimated air/fuel ratio. Here, low temperature refers to a temperature at which an air/fuel sensor cannot operate.

Abstract: An air-fuel ratio control system which calculates a basic injection amount of fuel by state detecting sensors (21) each of which detects an operating state of an internal combustion engine, air-amount detecting sensors (22) each of which detects an intake air amount, an air-fuel ratio sensor (23), and a predetermined data group. Further, the air-fuel ratio control system stores past amount data of injected fuel and air-fuel ratio data at each control cycle. A neuro-computation unit (29) reads values of the data detected by the sensors (21,22) and the stored data to obtain an air-fuel ratio estimate to calculate a correction injection amount of fuel by a neural network of a forward neuro-computing unit (210), which has learned beforehand about relations of the injected fuel amount, the detected air-fuel ratio, parameters, and dead time.

Abstract: A sensor for detecting the combustion pressure of an engine, in which an upper fixing member and a casing are fixed while a pre-load is being applied to the upper fixing member, so that a pre-load may be applied to a piezoelectric element. Moreover, a tubular diaphragm for transforming a pressure into a strain and a pressure receiving face for receiving the combustion pressure are connected to each other through a plunger so that they may be kept away from each other.

Abstract: A piezoelectric pressure sensor includes a generally elongated sensor housing, a pressure receiving plate disposed at a first end of the sensor housing with a first surface thereof serving as a pressure receiving surface for receiving a pressure applied from outside of the sensor housing, a pressure transmission member accommodated in the sensor housing with a first end thereof held in contact with a second surface of the pressure receiving plate, and a tubular piezoelectric element accommodated in the sensor housing with a first end thereof held in contact with a second end of the pressure transmission member. A pair of electrodes are formed on the external and internal surfaces of the piezoelectric element, respectively.

Abstract: A first link member (7), an upper-limit link member (9a), and a lower-limit link member (9b) are rotatably and axially coupled together. When the throttle is to be opened, the throttle valve (5) is electrically controlled by the motor (4) which has been under the control of an output from the accelerator opening sensing device (3), and at the same time, the throttle valve (5) is mechanically controlled by the wire (12) through the link members (7, 9a, 9b) in response to the degree of opening of the accelerator. A high degree of throttle operation such as traction control, idling control, constant speed run, etc. can be executed normally, and when an abnormality arises, the fail-safe function is at work to close the throttle valve (5).

Abstract: A vehicle behavior during driving is correctly grasped by computing and map-retrieving from output signal (.omega.y) of an angular velocity sensor (2) for detecting the angular velocity of the vehicle (11). A vehicle control apparatus of the present invention can correctly compensate the output signal (.omega.y) having error owing to the secular change or temperature change, etc. by using a zero-point calculation means (6, 16, 26, 36, 46, 56) for calculating zero-point signal (.omega.y0) and an angular velocity correction means (7, 17, 27, 37, 47, 57) for correcting the output signal (.omega.y) of the angular velocity sensor (2).

Abstract: A suspension control apparatus for a vehicle having at least one shock absorber with a controllable damping force. The suspension control apparatus includes a roll angular velocity sensor for detecting angular velocity about a roll axis of the vehicle, and control means for determining a bumpy-road driving state of the vehicle when an accumulation time exceeds a predetermined accumulation time. The control means adjusts the damping force of the shock absorber during the bumpy road driving state. The accumulation time represents the amount of time the angular velocity exceeds a predetermined angular velocity range during a first predetermined time period.

Abstract: A piezoelectric pressure sensor is provided with a sensor housing including an inner sensor housing, accommodating an piezoelectric element, and an outer sensor housing threaded to a test article. The inner sensor housing is attached to the outer sensor housing in such a manner that a prestress applied to the piezoelectric element does not change due to an axial strain in the outer sensor housing. The axial strain is produced when the outer sensor housing is mounted to a test article.

Abstract: Members as an upper fixing screw, a piezoelectric element, a pressure transmitting member are located closer to region of an engine to be measured and the like than a fitting thread portion of a sensor casing so that a pre-stress on the piezoelectric element can be constantly maintained at a predetermined value, thus enabling pressure measurement with a high degree of accuracy. Further, a projecting portion or a spacer is provided on the backside of a pressure receiving surface in order to ensure the surface contact between the pressure transmitting member and the back surface of the pressure receiving surface, thus preventing the stress from concentrating on corners of the bottom surface of the pressure transmitting member.

Abstract: Pitching motion of bouncing, bottoming, bumpyroad driving and braking of a vehicle during driving is correctly grasped by computing and map-retrieving from output signal of a vehicle speed sensor, output signal of a brake switch and output signal of a pitch angular velocity sensor for detecting angular velocity about a pitch axis of the vehicle; and pitching motion of the vehicle is restrained by the adjusting damping force of shockabsorbers of the suspension control apparatus.

Abstract: A vehicle behavior during cornering and turning is correctly grasped by computing and map-retrieving from output signal (V) of a vehicle speed sensor (1) and output signal (.omega.y) of a yaw angular velocity sensor (2) for detecting angular velocity about a yaw axis (B) of the vehicle (11), and rolling motion of the vehicle (11) during ordinary-turning or quick-turning is restrained by increasing damping force of shockabsorbers (3) of the suspension control apparatus.

Abstract: An exhaust gas filtering element is provided for filtering diesel particulates. The system comprises two filter elements disposed parallel to each other, a burner mechanism, and a four-way valve mechanism for switching over an exhaust gas flow and a preheated gas flow obtained by combustion in the burner mechanism. The exhaust gas flow is generally passed uniformly through the two filter elements which filter off particulates. However, when regeneration is required, an ellipitical vane, provided in a cylinder of the four-way valve mechanism, is rotated so as to cut off the exhaust gas flow passing through one of the filter elements and cause the preheated gas to flow through this filter, whereby particulates are oxidized and incinerated. At this time, the exhaust gas flow is passed through the other filter element, without any particulates being emitted into the atmosphere. Then, the exhaust gas flow and the preheated gas flow are switched by rotating the vane so that the other filter element is regenerated.