Ball Wave Inc.

Tohoku University

Toshihiro Tsuji

Kazushi Yamanaka

Toru Oizumi

Nobuo Takeda

Yusuke Tsukahara

Shingo Akao

Hideyuki Fukushi

Tatsuhiro Okano

Nagisa Sato

Osamu Hirayama

Naoya Iwata

Takamitsu Iwaya

Maki Sugawara

A system for calibrating a moisture sensor encompasses a processing unit (). The processing unit () includes a reference data obtaining LCKT (), a subject data obtaining LCKT () and a relationship calculating LCKT (). The reference data obtaining LCKT () obtains reference data, after injecting water-vapor with known concentrations into an analyzer. The subject data obtaining LCKT () measures subject data indicating temporal variation of output-responses of a subject sensor element of the analyzer under test. The relationship calculating LCKT () compares the subject data with the reference data, and calculates relationships between the output-responses of the subject sensor element and the known concentrations.

System, method and program for calibrating moisture sensor

System and method for measuring a gas concentration are provided. A ball sensor generates a collimated beam of a surface acoustic wave including fundamental wave of first frequency and harmonic wave of second frequency, which propagates through a orbital path on piezoelectric ball while passing through sensitive film to adsorb a target gas. Temperature control unit controls ball temperature of the ball sensor. Signal processing unit transmits a burst signal to sensor electrode of the ball sensor to excite the collimated beam, receives burst signals after the collimated beam has propagated a predetermined number of turns around the piezoelectric ball, and calculates the gas concentration and the ball temperature by first and second relative changes in delay times of the first and second frequencies, respectively, using waveform data of the burst signals.

System, method and computer program product for measuring gas concentration

A collimated beam () of a surface acoustic wave propagates on a piezoelectric substrate () while passing through sensitive film () to adsorb a sensing gas. Signal processing unit () transmits an exciting burst signal to sensor electrode () to excite the collimated beam (), receives first and second returned burst signals after the collimated beam () has propagated, and calculates a target gas parameter by a target leakage factor of the background gas and a relation between reference gas parameters and reference leakage factors of reference gases, the leakage factor is provided by first and second attenuations of the first and second returned burst signals, respectively, using waveform data of the first and second returned burst signals.

System, method and computer program product for gas analysis

A standard-moisture generator includes a flow controller configured to control a flow of a gas, a dryer connected to the flow controller, configured to absorb water molecules in the gas and to generate a dry gas having a background moisture, a moisture cell connected to the dryer, configured to add an object moisture to the dry gas, and a delay member connected to the moisture cell, configured to pass the dry gas with a delay time depending on a concentration of the background moisture in the dry gas.

Standard-moisture generator, system using the standard-moisture generator, method for detecting abnormality in standard-moisture and computer program product for detecting the abnormality

When frequencies used in the two-frequency measurement of a SAW sensor are represented by fand f(f&#x3e;f), an electrical signal processing device is provided without use of oversampling at a frequency higher than twice the frequency for a two-system low-frequency conversion circuit, in which temperature compensation with the same accuracy as the case where these are used can be realized. Narrow band frequency filtering is applied to a waveform after roundtrips in a delay line type SAW sensor capable of transmitting and receiving multiple frequencies, the two frequencies fand f(f&#x3e;f) are extracted, and a delay time is determined utilizing an aliasing obtained by applying undersampling at a frequency lower than twice the frequency f.

Electrical signal processing device

A gas analyzer that can be miniaturized and detect a wide variety of gases with high sensitivity, and a method of gas analysis. A separation column is configured so as to pass a sample gas together with a carrier gas through the inside thereof. A surface acoustic wave device has a base material with an annularly continuous annular surface formed of at least a part of a spherical surface; a surface acoustic wave generating means capable of generating a surface acoustic wave that propagates along the annular surface; and a plurality of reaction parts provided along the annular surface so as to change a predetermined physical quantity of the surface acoustic wave in response to the components of the sample gas. The surface acoustic wave device is arranged so that the sample gas passing through the separation column is reacted with the reaction parts. The measuring part can measure a physical quantity of the surface acoustic wave propagating along the annular surface, and the components of the sample gas can be analyzed on the basis of the measured physical quantity.

Growing community of inventors

Sendai, Japan

Toshihiro Tsuji