Abstract: An engine ECU executes a program including the steps of: calculating a correlation coefficient K based on the result of comparing a vibration waveform of an engine and a knock waveform model stored previously; calculating a magnitude value LOG(V) from the magnitude V detected based on a signal transmitted from a knock sensor; creating frequency distribution of magnitude values LOG(V) by using magnitude values LOG(V) in an ignition cycle in which the correlation coefficient K larger than a threshold K(1) is calculated; and counting knock proportion KC by using the created frequency distribution. If the vibration waveform includes a waveform of vibration of noise components, the correlation coefficient K is calculated to be smaller comparing with a case of not including it.

Abstract: An engine ECU includes a bandpass filter (1) extracting only vibrations at a first frequency band A, a bandpass filter (2) extracting only vibrations at a second frequency band B, a bandpass filter (3) extracting only vibrations at a third frequency band C, and a bandpass filter (4) extracting only vibrations at a fourth frequency band D including the first to third frequency bands A-C. The engine ECU determines whether knocking occurred or not based on a vibration waveform of the fourth frequency band D and a peak value in magnitude of vibrations in a synthesized waveform of the first to third frequency bands.

Abstract: An engine ECU executes a program including: determining whether or not a condition for stopping knocking determination is satisfied; setting a flag of stopping correction of a determination value to “ON”; calculating a knock determination level based on the extracted magnitude value; and when the correction stop flag is not “ON”, decreasing or increasing the determination value in accordance with a knock proportion KC that is a proportion of magnitude values greater than the knock determination level. The knock determination level is calculated even when the correction stop flag is “ON”.

Abstract: An engine ECU 200 includes a bandpass filter (1), a bandpass filter (2), and a bandpass filter (3). The bandpass filter (1) extracts only vibrations at a first frequency band A from the vibrations detected by a knock sensor. The bandpass filter (2) extracts only vibrations at a second frequency band B from the vibrations detected by the knock sensor. The bandpass filter (3) extracts only vibrations at a third frequency band C from the vibrations detected by the knock sensor. The first to third frequency bands A-C are identical in bandwidth. The engine ECU calculates a peak value in magnitude of vibrations in a synthesized waveform of these frequency bands, and determines whether knocking occurred or not based on the peak value.

Abstract: An engine ECU executes a program including a step of, when an absolute value of a difference between a determination value V(KX) used for determining presence or absence of knocking and a maximum value V(MAX) of magnitude value LOG(V), which is obtained by logarithmically converting a magnitude V detected based on a signal sent from a knock sensor, is greater than the product of a standard deviation ? and a coefficient U(3) in a frequency distribution of magnitude values LOG(V) for N cycle(s), setting a value obtained by adding the product of the standard deviation ? and the coefficient U(3) to the maximum value V(MAX) of the magnitude value LOG(V) as the determination value V(KX).

Abstract: An engine ECU executes a program including: a step (S310) of multiplying a correction amount of a determination value V(KX) by Q, when deviation L between an approximation value V(R), which is an average value of determination values V(KX) corrected according to the occurrence frequency of knocking, and an approximation value V(R?1) previously calculated is greater than a predetermined value (NO in S306) or when the number of times where deviation L is determined to be smaller than a predetermined value is smaller than a predetermined number of times (NO in S308); and a step (S312) of multiplying the correction amount of the determination value V(KX) by 1/P, when the number of times where the deviation L is determined to be smaller than a predetermined value is greater than a predetermined number of times (YES in S308). By comparing the determination value V(KX) and knock magnitude, determination of knocking is made, and ignition timing is advanced or retarded.

Abstract: An engine ECU executes a program including: determining whether or not a condition for stopping knocking determination is satisfied; setting a flag of stopping correction of a determination value to “ON”; calculating a knock determination level based on the extracted magnitude value; and when the correction stop flag is not “ON”, decreasing or increasing the determination value in accordance with a knock proportion KC that is a proportion of magnitude values greater than the knock determination level. The knock determination level is calculated even when the correction stop flag is “ON”.

Abstract: An engine ECU executes a program including a step of calculating intensity values LOG(V), a step of detecting vibration waveforms, a step of calculating a correlation coefficient K based on vibration waveforms, a step of preparing frequency distribution of intensity values LOG(V) smaller than a threshold V(1) and intensity values LOG(V) in an ignition cycle where correlation coefficient K is larger than a threshold K(1), a step of calculating a knock determination level V(KD) based on a median V(50) and a standard deviation ? of intensity values LOG(V), and a step of counting the number of intensity values LOG(V) larger than knock determination level V(KD) as the number of times that knocking has occurred.

Abstract: An engine ECU executes a program including the steps of: calculating a correlation coefficient K based on the result of comparing a vibration waveform of an engine and a knock waveform model stored previously; calculating a magnitude value LOG(V) from the magnitude V detected based on a signal transmitted from a knock sensor; creating frequency distribution of magnitude values LOG(V) by using magnitude values LOG(V) in an ignition cycle in which the correlation coefficient K larger than a threshold K(1) is calculated; and counting knock proportion KC by using the created frequency distribution. If the vibration waveform includes a waveform of vibration of noise components, the correlation coefficient K is calculated to be smaller comparing with a case of not including it.

Abstract: An engine ECU executes a program including the steps of: calculating a correlation coefficient K based on the result of comparing a vibration waveform of an engine and a knock waveform model stored previously; calculating a magnitude value LOG(V) from the magnitude V detected based on a signal transmitted from a knock sensor; creating frequency distribution of magnitude values LOG(V) by using magnitude values LOG(V) in an ignition cycle in which the correlation coefficient K larger than a threshold K(1) is calculated; and counting knock proportion KC by using the created frequency distribution. If the vibration waveform includes a waveform of vibration of noise components, the correlation coefficient K is calculated to be smaller comparing with a case of not including it.

Abstract: The object is to provide a construction method of an information-communicable underground pipe whereby communication cables can be readily laid in an underground pipeline having a main pipe and branch pipes branched therefrom thereby allowing the underground pipeline to be used as an information-communicable underground pipe, and to provide a construction structure and a construction member therefor.

Abstract: An engine ECU executes a program including the steps of: comparing a vibration waveform of an engine and a knock waveform model stored in advance to calculate a correlation coefficient K; prohibiting correction when a correction prohibiting condition of a determination value V(KX) is satisfied, the determination value V(KX) compared with a knock magnitude N calculated from the correlation coefficient K so as to control the ignition timing; and correcting the determination value V(KX) based on a magnitude value LOG(V) calculated from a magnitude V of vibration in an ignition cycle in which the correlation coefficient K greater than a threshold value K(1) is calculated when the correction prohibiting condition of determination value V(KX) is not satisfied. The correlation coefficient K is calculated as a smaller value when the vibration waveform includes a waveform of vibration of a noise component as compared with that when the vibration waveform does not include it.

Abstract: An engine ECU executes a program including a step of, when an absolute value of a difference between a determination value V(KX) used for determining presence or absence of knocking and a maximum value V(MAX) of magnitude value LOG(V), which is obtained by logarithmically converting a magnitude V detected based on a signal sent from a knock sensor, is greater than the product of a standard deviation ? and a coefficient U(3) in a frequency distribution of magnitude values LOG(V) for N cycle(s), setting a value obtained by adding the product of the standard deviation ? and the coefficient U(3) to the maximum value V(MAX) of the magnitude value LOG(V) as the determination value V(KX).

Abstract: An engine ECU executes a program including the steps of: calculating a correlation coefficient K based on the result of comparing a vibration waveform of an engine and a knock waveform model stored previously; calculating a magnitude value LOG(V) from the magnitude V detected based on a signal transmitted from a knock sensor; creating frequency distribution of magnitude values LOG(V) by using magnitude values LOG(V) in an ignition cycle in which the correlation coefficient K larger than a threshold K(1) is calculated; and counting knock proportion KC by using the created frequency distribution. If the vibration waveform includes a waveform of vibration of noise components, the correlation coefficient K is calculated to be smaller comparing with a case of not including it.

Abstract: A laying method for laying communication cables (16) is provided which allows to lay optical fiber cables (20) in an underground pipeline such as a sewage pipe neither placing direct tension nor allowing slack on them, and for a main pipe in which a plurality of optical fiber cables (20) are to be laid, the method also allows to lay optical fiber cables (20) in the upper space of inside the pipeline and to obviate the need of an expensive robot for the laying operation. In the proposed laying method, a high-strength low-elongation tension member is disposed to be slidable in the lengthwise direction along each optical fiber cable (20, 21, 22), and the tension members (25, 26, 27) are drawn into the underground pipeline (1) to tension the trunk tension member (25) thereby stretching the trunk tension member (25) substantially straight in the underground pipeline (1), and thus the optical fiber cables (20, 21, 22) are laid in the upper space of inside the underground pipeline (1).

Abstract: An engine ECU includes a bandpass filter (1) extracting only vibrations at a first frequency band A, a bandpass filter (2) extracting only vibrations at a second frequency band B, a bandpass filter (3) extracting only vibrations at a third frequency band C, and a bandpass filter (4) extracting only vibrations at a fourth frequency band D including the first to third frequency bands A-C. The engine ECU determines whether knocking occurred or not based on a vibration waveform of the fourth frequency band D and a peak value in magnitude of vibrations in a synthesized waveform of the first to third frequency bands.

Abstract: An engine ECU 200 includes a bandpass filter (1), a bandpass filter (2), and a bandpass filter (3). The bandpass filter (1) extracts only vibrations at a first frequency band A from the vibrations detected by a knock sensor. The bandpass filter (2) extracts only vibrations at a second frequency band B from the vibrations detected by the knock sensor. The bandpass filter (3) extracts only vibrations at a third frequency band C from the vibrations detected by the knock sensor. The first to third frequency bands A-C are identical in bandwidth. The engine ECU calculates a peak value in magnitude of vibrations in a synthesized waveform of these frequency bands, and determines whether knocking occurred or not based on the peak value.

Abstract: An engine ECU executes a program including a step of calculating intensity values LOG(V), a step of detecting vibration waveforms, a step of calculating a correlation coefficient K based on vibration waveforms, a step of preparing frequency distribution of intensity values LOG(V) smaller than a threshold V(1) and intensity values LOG(V) in an ignition cycle where correlation coefficient K is larger than a threshold K(1), a step of calculating a knock determination level V(KD) based on a median V(50) and a standard deviation ? of intensity values LOG(V), and a step of counting the number of intensity values LOG(V) larger than knock determination level V(KD) as the number of times that knocking has occurred.

Abstract: An engine ECU executes a program including the steps of: comparing a vibration waveform of an engine and a knock waveform model stored in advance to calculate a correlation coefficient K; prohibiting correction when a correction prohibiting condition of a determination value V(KX) is satisfied, the determination value V(KX) compared with a knock magnitude N calculated from the correlation coefficient K so as to control the ignition timing; and correcting the determination value V(KX) based on a magnitude value LOG(V) calculated from a magnitude V of vibration in an ignition cycle in which the correlation coefficient K greater than a threshold value K(1) is calculated when the correction prohibiting condition of determination value V(KX) is not satisfied. The correlation coefficient K is calculated as a smaller value when the vibration waveform includes a waveform of vibration of a noise component as compared with that when the vibration waveform does not include it.

Abstract: A knock waveform model (thick line) is prepared by correcting a line (thin line) representing an average value of a vibration waveform measured in advance to have more moderate inclination. The knocking determination device determines whether knocking occurred in an engine or not, based on a result of comparison between the knock waveform model and a waveform detected by a knock sensor.