Abstract: A speaker includes a yoke configured to form a magnetic circuit, a first magnet provided in a fixed manner, a voice coil provided in a gap through which a magnetic flux of the magnetic circuit is configured to pass, a diaphragm connected to the voice coil and configured to vibrate with the voice coil, a second magnet provided on a diaphragm unit including the voice coil and the diaphragm, and a magnetic sensor provided at a position through which both of a first magnetic flux generated by the first magnet and a second magnetic flux generated by the second magnet are configured to pass, wherein a direction of the first magnetic flux and a direction of the second magnetic flux are different from each other.

Abstract: In some implementations, an output of a first channel of an echo cancellation variable filter having an output of a first microphone output from a second speaker as an input is added to an output of a second microphone. An echo cancellation coefficient updating unit updates the filter coefficient of the first channel so that the error that is the output of a second adder is minimized. Using the output of the second channel that uses the output of a sound source device output from the first speaker as an input and shares the filter coefficient with the first channel as a reference signal, and the output of the second microphone as an error, the noise cancellation coefficient updating unit updates the filter coefficient of the noise cancellation variable filter that generates a noise-canceling sound to be output from the output of the sound source device to the second speaker.

Abstract: A signal e(z) obtained by subtracting echo-canceling sound from an output of a second microphone is used as an error of an echo cancellation adaptive filter and a noise cancellation adaptive filter, and an output of a first sound source device is added to the signal e(z) and output from a first speaker. The echo cancellation adaptive filter generates echo-canceling sound from an addition signal of the output of the second sound source device and the output of the first microphone such that the signal e(z) is minimized. The noise cancellation adaptive filter generates the noise-canceling sound from the output of the first sound source device such that the signal e(z) is minimized, and outputs the noise-canceling sound from the second speaker.

Abstract: The invention is intended to provide a method for quenching a steel pipe, equipment for quenching a steel pipe, and a method of manufacturing a steel pipe that enable a steel pipe to be conveyed at high speed. The method for quenching a steel pipe includes the steps of: conveying a steel pipe onto a rotatable supporting member using a walking-arm type revolving conveyance apparatus; and rapidly cooling the steel pipe with first spray nozzles disposed above the pipe while the steel pipe is being rotated about a pipe axis of the steel pipe on the rotatable supporting member in a state where movements of the steel pipe in a direction parallel to and in a direction perpendicular to the pipe axis are stopped.

Abstract: Adaptive filters output a cancellation sound from a speaker, a selector selects outputs of a plurality of auxiliary filters each corresponding to different positions, a subtractor subtracts the selected output from the output of the microphone and outputs the subtracted output to the adaptive filter as an error signal, and a position detection device detects a position of a head of a user. A transfer function estimated so that the error signal becomes 0 when noise is canceled at the corresponding position is preset in the auxiliary filter. When the auxiliary filter corresponding to the position close to the head of the user changes, the switching control unit stepwise increases the frequency with which the output of the auxiliary filter is selected by the selector to 100%.

Abstract: With respect to a noise reduction device using a speaker and a microphone corresponding to each seat in a vehicle to reduce a noise in each seat, the noise reduction device includes, a signal processing unit configured to generate a canceling sound that reduces a noise at an ear of an occupant in a predetermined seat by using an auxiliary filter, an operation setting unit configured to disable operations of a speaker and a microphone corresponding to each empty seat in the vehicle, and an auxiliary filter setting unit configured to change a setting value of the auxiliary filter used by the signal processing unit to generate the canceling sound in accordance with the number of occupants in seats other than the predetermined seat, the seats affecting the noise in the predetermined seat.

Abstract: A first seat noise control device corrects sound collected by a microphone to sound at a listening position of a user seated on a first seat, generates a cancel sound that cancels, at the first seat, the sound of a second seat audio source output from a second seat speaker by using an adaptive filter, and outputs the cancel sound from a first seat speaker. A second seat noise control device corrects the sound collected by the microphone to sound at the listening position of the user seated on the second seat, generates a cancel sound that cancels, at the second seat, the sound of a first seat audio source output from the first seat speaker using an adaptive filter, and outputs the cancel sound from the second seat speaker.

Abstract: In a first system signal processing unit, a first system auxiliary filter generates a correction signal for correcting an error signal from a noise signal, a first system subtractor subtracts the correction signal from an output of a first microphone to obtain an error signal, an adaptive filter performs an adaptive operation using the error signal to generate a cancel sound output from a first speaker, and a DMS detects a position of a user's ear. When the position of the user's ear moves, the controller stops the adaptive operation, updates the transfer function of the first system auxiliary filter to the transfer function corresponding to the noise cancel position matching the position of the user's ear, gradually changes the transfer function of the adaptive filter to the transfer function corresponding to the matching noise cancel position, and resumes the adaptive operation after the change is completed.

Abstract: In a first system signal processing unit, an adaptive filter generates a noise cancel sound, a first system selector selects an output of a first system auxiliary filter corresponding to a noise cancel position matching a detected position of a right ear of a user from a plurality of first system auxiliary filters corresponding to different noise cancel positions, and a first system subtractor subtracts the selected output from an output of a first microphone and outputs the subtracted result as an error signal to a first system adaptive filter and a second system adaptive filter of a second system signal processing unit. The noise cancel positions are arranged at predetermined intervals in a space where the user can move the right ear due to turning and side bending of the head within a predetermined range in the up-down and front-back directions.

Abstract: A transfer function of a first variable filter is updated to output, from an output of a first seat microphone, a cancel sound that minimizes a level of a signal obtained by subtracting an output of an auxiliary filter that generates a correction signal for correcting a difference between positions of the first seat microphone and the first seat. In the ICC mode in which the uttered voice of the user in the first seat is output from a second seat speaker, a selector sets an uttered voice Dp output from the second seat speaker as an input to the first variable filter, and in the non-ICC mode, the selector sets an output sound of a second seat audio source output from the second seat speaker as an input to the first variable filter. The uttered voice Dp is generated by removing a component of the cancel sound from the output of the first seat microphone.

Abstract: A first variable filter receives a sound of a second seat audio source as an input and generates a cancel sound for canceling the sound of the second seat audio source at a first seat. The transfer functions of the first variable filter and the second variable filter are updated such that the level of a signal obtained by subtracting the output of the auxiliary filter that generates a correction signal for correcting the difference between the positions of the first seat microphone and the first seat and the output of the second variable filter that receives the sound of the first seat audio source from the output of the first seat microphone is minimized. While the level of the signal exceeds a threshold, the signal is relayed to the second seat as a spoken voice.

Abstract: Adaptive operations of a first noise control system and a second noise control system may include a speaker that outputs noise cancellation sound, a microphone that detects an error signal, an auxiliary filter that generates, from a noise signal, a correction signal that corrects the error signal so that a difference in a position between the microphone and a noise cancellation position is compensated, and an adaptive filter that performs an adaptive operation using the corrected error signal to generate the noise cancellation sound from the noise signal are alternately performed. A transfer function learned in a state in which the second noise control system is stopped is set in the auxiliary filter of the first noise control system, and a transfer function learned in a state in which the adaptive operation of the first noise control system is stopped is set in the auxiliary filter of the second noise control system.

Abstract: Two subsystems, each including a microphone, a speaker, a canceling sound-generating adder, an error-computing adder, and two adaptive filters and two auxiliary filters that accept two noises as input, are provided in correspondence with two cancellation positions. Each canceling sound-generating adder adds together the outputs from the adaptive filters and outputs the result to the speaker of each subsystem. Each error-computing adder adds together the output from the microphone of the subsystem and the output from the auxiliary filter of the subsystem, and the result is treated as the error of the adaptive filters of each subsystem. A transfer function is learned in advance and set in each auxiliary filter such that each error computed by each error-computing adder becomes zero (0) when a transfer function in which each noise is canceled at each cancellation position in a predetermined standard acoustic environment is set in each adaptive filter.

Abstract: The invention is intended to provide a method for quenching a steel pipe, equipment for quenching a steel pipe, and a method of manufacturing a steel pipe that enable a steel pipe to be conveyed at high speed. The method for quenching a steel pipe includes the steps of: conveying a steel pipe onto a rotatable supporting member using a walking-arm type revolving conveyance apparatus; and rapidly cooling the steel pipe with first spray nozzles disposed above the pipe while the steel pipe is being rotated about a pipe axis of the steel pipe on the rotatable supporting member in a state where movements of the steel pipe in a direction parallel to and in a direction perpendicular to the pipe axis are stopped.

Abstract: With respect to a noise reduction device using a speaker and a microphone corresponding to each seat in a vehicle to reduce a noise in each seat, the noise reduction device includes, a signal processing unit configured to generate a canceling sound that reduces a noise at an ear of an occupant in a predetermined seat by using an auxiliary filter, an operation setting unit configured to disable operations of a speaker and a microphone corresponding to each empty seat in the vehicle, and an auxiliary filter setting unit configured to change a setting value of the auxiliary filter used by the signal processing unit to generate the canceling sound in accordance with the number of occupants in seats other than the predetermined seat, the seats affecting the noise in the predetermined seat.

Abstract: Audio (noise source) is output as a cancellation sound through a variable filter and a first filter, and transmitted to the second filter. A subtractor subtracts an output of a second filter from an output of a microphone, and an adaptive algorithm execution unit updates a transfer function of the variable filter so that the subtracted result becomes zero (0). A transfer function A for the first filter is a transfer function which can cancel noise at a position of a user's ear by setting, as the cancellation sound, a sound obtained by applying the transfer function A to audio at the time of learning, and a transfer function B for the second filter is a transfer function which can eliminate, for the cancellation sound, a difference between a sound obtained by applying the transfer function B to audio and the output of the microphone.

Abstract: A first cancellation signal output from a first speaker cancels noise at a first cancellation point, which is a typical position of the right ear of a user, together with a second cancellation signal output from a second speaker. In addition, the second cancellation signal output from the second speaker cancels noise at a second cancellation point, which is a typical position of the left ear of the user, together with the first cancellation signal output from the first speaker. The first speaker and the second speaker are arranged side by side on a second line segment, which passes through the midpoint of a first line segment connecting the first cancellation point and the second cancellation point to each other and is perpendicular to the first line segment, and a range where the relationship between noise and the first cancellation signal and the second cancellation signal is the same as that at the cancellation point is extended.

Abstract: Adaptive filters output a cancellation sound from a speaker, a selector selects outputs of a plurality of auxiliary filters each corresponding to different positions, a subtractor subtracts the selected output from the output of the microphone and outputs the subtracted output to the adaptive filter as an error signal, and a position detection device detects a position of a head of a user. A transfer function estimated so that the error signal becomes 0 when noise is canceled at the corresponding position is preset in the auxiliary filter. When the auxiliary filter corresponding to the position close to the head of the user changes, the switching control unit stepwise increases the frequency with which the output of the auxiliary filter is selected by the selector to 100%.

Abstract: Two subsystems, each including a microphone, a speaker, a canceling sound-generating adder, an error-computing adder, and two adaptive filters and two auxiliary filters that accept two noises as input, are provided in correspondence with two cancellation positions. Each canceling sound-generating adder adds together the outputs from the adaptive filters and outputs the result to the speaker of each subsystem. Each error-computing adder adds together the output from the microphone of the subsystem and the output from the auxiliary filter of the subsystem, and the result is treated as the error of the adaptive filters of each subsystem. A transfer function is learned in advance and set in each auxiliary filter such that each error computed by each error-computing adder becomes zero (0) when a transfer function in which each noise is canceled at each cancellation position in a predetermined standard acoustic environment is set in each adaptive filter.

Abstract: Audio (noise source) is output as a cancellation sound through a variable filter and a first filter, and transmitted to the second filter. A subtractor subtracts an output of a second filter from an output of a microphone, and an adaptive algorithm execution unit updates a transfer function of the variable filter so that the subtracted result becomes zero (0). A transfer function A for the first filter is a transfer function which can cancel noise at a position of a user's ear by setting, as the cancellation sound, a sound obtained by applying the transfer function A to audio at the time of learning, and a transfer function B for the second filter is a transfer function which can eliminate, for the cancellation sound, a difference between a sound obtained by applying the transfer function B to audio and the output of the microphone.