Hitachi, Ltd.

Hitachi-high-technologies Corporation

Kuniomi Ogata

Akihiko Kandori

Tsuyoshi Miyashita

Keiji Tsukada

Ryuzo Kawabata

Takako Mizoguchi

Daisuke Suzuki

Yuko Sano

Atsushi Maki

Tsukasa Funane

Yusuke Seki

Masahiro Murakami

To perform respiratory monitoring and cardiac-output measurement on general patients, an aspect of a biological measurement apparatus includes: at least two electrodes that are attached to a living body; a power supply that causes an AC current to flow between the two electrodes; at least two coils that are placed so as to sandwich a line linking the two electrodes, and detect a magnetic field related to a change in the AC current accompanying a change in impedance of the living body; and a detection circuit that performs addition or subtraction of signals related to the magnetic field detected with the two coils, and outputs the signals as a change in the impedance.

Biological measurement method

A compression depth calculation system is configured to calculate the compression depth which is a magnitude of depression of the compressed object generated by the compression and includes a measuring apparatus to be mounted on the object, and a compression depth calculating apparatus is configured to calculate the compression depth on the basis of information from the measuring apparatus. The compression depth calculation apparatus calculates a coefficient of transformation on the basis of a second-order differential waveform created for the information acquired from a magnetic sensor and acceleration information acquired from an acceleration sensor, creates a displacement waveform of a compressed portion by multiplying the acquired information by the coefficient of transformation, and calculates the compression depth on the basis of the displacement waveform.

Compression depth calculation system and compression depth calculation method

For measuring hardness of an object, a measurement apparatus is pushed against the object and a degree of hardness calculation system calculates hardness based on information from the measurement apparatus. The measurement apparatus includes an acceleration sensor which outputs first information of acceleration of a contact area of the measurement apparatus, and a second sensor, such as a magnetic sensor or a pressure sensor, which outputs second information based on pressure applied to the contact area. The degree of hardness calculation system generates a second-derivative waveform by twice differentiating a waveform based on the output of the second sensor, compares the second-derivative waveform and the information of acceleration from the acceleration sensor, and calculates hardness of the object based on the comparison result.

Degree of hardness measurement system and degree of hardness measurement method

A movement analysis display apparatus includes a analyzing unit for analyzing waveform data of a time series which is acquired from a movement sensor, and a display unit for displaying an analysis result that is analyzed by the analyzing unit. The analyzing unit includes a movement waveform generating section for generating a movement waveform from the waveform data, an energy balance value calculating means for calculating a movement energy ratio in opposed movement directions in a velocity waveform, an envelope curve generating section for generating an envelope curve at a given time width in a distance waveform, and a time integration curve analyzing section for integrating a movement waveform with respect to time.

Movement analysis display apparatus and movement analyzing method

A CAM (current arrow map)and another CAMare obtained from magnetocardiogram waveforms measured from both front and back sides of a subject using data at a point of time of an R-wave peak, then the coordinates of the CAMare inverted in both x and y axis directions to obtain a CAM. The coordinates of each of the CAMsandare converted to polar coordinates to obtain CAMsandat both front and back sides of the subject. After that, the CAMis adjusted to the CAMin scale to obtain a CAM, and CAMsandare combined. Then, the CAM data at measuring points on each measuring-points-missing radius vector is inserted through an arithmetic processing by interpolation so that CAM data at every measuring point on a planispheric chartare connected to each another consecutively.

Biomagnetic measurement apparatus

There is provided a magnetic shield which can shield external magnetic fields in the direction of an axis of a tubular magnetic shield and in the direction vertical to the axis. A magnetic shield has a cylindrical ferromagnetic substance-having openings on both ends and two superconducting loops housed in the respective insides of superconducting loop containers-,-. The superconducting loops are constructed of high critical temperature superconducting wire. The two superconducting loops have semicircle shapes and are arranged in x-direction so as to be symmetrical with respect to an axis of the cylindrical ferromagnetic substance-. The superconducting loop containers-,-are arranged in the insides near both open ends of the cylindrical ferromagnetic substance-with supports. The superconducting loops are arranged to be vertical to the axis of the cylindrical ferromagnetic substance-. The superconducting loops are cooled by liquid nitrogen or a refrigerator. A lightweight, small magnetic shield having high operability can be realized.

Magnetic shields and instruments for measuring biomagnetic fields

A living body inspection apparatus which quantitatively evaluates timings of movements (bending and stretching) of fingers. The apparatus includes: a movement sensor including a transmitter coil for generating a magnetic field and a plurality of receiver coils for receiving the generated magnetic field from the transmitter coil; analyzing means which analyzes time-series waveform data acquired from the movement sensor; and display means which displays a result of analysis made by the analyzing means. For comparison of waveform data, the analyzing means includes distance waveform generating means for generating distance waveforms corresponding to the waveform data, and standard point generating means for generating standard points based on standard distances in the distance waveforms.

Living body inspection apparatus

A biomagnetic measurement technique which can obtain a potential waveform corresponding to a ventricular muscle cell action potential in a non-invasive manner. The biomagnetic measurement apparatus including an operating circuit for magnetometer. The output data of the operating circuit for the magnetometer is collected and a current vector at time t is calculated. Further, an absolute value Ixy of the current vector, a potential waveform V (t) in time corresponding to depolarization of a heart from the absolute value of the current vector, and a potential waveform V (t) in a refractory period of the heart to a period corresponding to repolarization from the absolute value of the current vector are calculated.

Disclosed herein is a biomagnetic measurement apparatus capable of visualizing cardiac electrical current distributions with information on the cardiac morphology of a subject. A magnetic field component in the z direction, vertical to the chest surface of a subject, is measured from two directions, front and back of the chest, and then to calculate the current distributions in the two directions and the distributions of the amplitudes of those current distributions. A three-dimensional standard heart model is created from average data on the cardiac morphology obtained from plural healthy subjects. An optimal position of the model is determined using the coordinates of the sinus node and the coordinates of the left ventricle. Then, a weight coefficient is obtained by front and back current distributions and front and back the distributions of the amplitudes of those current distributions on a set boundary of the model.

A biomagnetic field measuring apparatus for performing (1) processes for removing a magnetic field waveform generated by a maternal heart from a waveform of a biomagnetic field measured, (2) processes for obtaining a template waveform of a magnetic field waveform generated by the fetal heart from a waveform, from which the magnetic field waveform generated by the maternal heart has been removed, (3) processes for obtaining a waveform of a cross correlation coefficient between the waveform, from which the magnetic field waveform generated by the mother's hears was removed, and the template waveform, and (4) a process for detecting peaks from a waveform of the cross correlation coefficient, and displaying times of appearance of the detected peaks on a display unit.

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Kokubunji, Japan

Kuniomi Ogata