Abstract: A flow rate control device includes a flowmeter that detects a flow rate of a fluid discharged from a fluid machine driven by a motor, and a controller that changes a frequency of a drive input voltage for driving the motor. The controller stores a tuning frequency table recording relationships between a plurality of difference ranges each of which defines a range to which an absolute value of a difference between the flow rate of the fluid and the target flow rate belongs by a lower limit value and an upper limit value of the range, and a plurality of tuning frequencies defined correspondingly to the respective difference ranges. The controller decides, based on a difference between the flow rate of the fluid and the target flow rate and the tuning frequency table, the tuning frequency corresponding to the difference between the converted flow rate and the target flow rate.

Abstract: A flow rate control device according to one embodiment includes: a flowmeter that repeatedly generates a pulse signal based on flow of a fluid discharged from a fluid machine driven by a brushless motor or AC motor, such that a pulse width of the pulse signal is inversely proportional to a flow rate of the fluid; an FV converter that makes frequency-voltage conversion of the pulse signal and generates a voltage value corresponding to the pulse signal; and a controller that changes a frequency of a drive input voltage for driving the brushless motor or AC motor based on a difference between a converted flow rate of the fluid converted based on the voltage value generated by the FV converter and a preset target flow rate.

Abstract: A technique facilitates seismic exploration by identifying time differences between clocks employed during the seismic exploration. According to an embodiment, a seismic signal is output from a source and has an incident wave and a reflected wave. The seismic signal is received by at least one receiver which outputs data to a control system. The control system is employed to compare a symmetry of the propagation of the incident wave and the reflected wave. The symmetry data is then used to determine a temporal change of the time base of the at least one receiver.

Abstract: A technique facilitates geophysical exploration by employing a tool wrapped with an optical fiber. Additionally, an orientation sensor is coupled to the tool and is operable to provide data regarding orientation of the tool. A processing system, which may include an optical interrogation system, cooperates with the optical fiber and with the orientation sensor to obtain acoustic data. For example, the processing system collects tool orientation data and also strain data obtained from a location along the wrapped optical fiber. The strain data results from excitation of an acoustic signal from a suitable acoustic source.

Abstract: A technique facilitates geophysical exploration and comprises deploying an optical fiber in a borehole formed in a formation. A seismic signal, e.g. seismic waves, is excited into the formation, and an optical interrogation system is used to obtain data at a plurality of fixed, sampling locations along the optical fiber. The data is processed to determine features in the formation. Based on the processed data, updated sampling locations are selected along the optical fiber to enable further analysis of the features of interest.

Abstract: A technique facilitates seismic wave detection with a seismic receiver. The seismic receiver has a tool body, a vibrationally isolated sensor package mounted in the tool body, and a plurality of contact shoes. The contact shoes are mounted around the sensor package in a distribution which enables three-point contact with a surrounding wellbore wall regardless of the azimuthal orientation of the sensor package.

Abstract: A seismic sensor for a downhole tool positionable in a wellbore penetrating a subterranean formation. The seismic sensor includes a sensor housing, a bobbin supported in the sensor housing along an axis thereof, at least one coil wound about the bobbin (the coil movably supportable within the sensor housing by at least one spring), at least one magnet positionable about the bobbin to generate a magnetic field with the at least one coil whereby seismic vibrations are detectable, and a filler fluid disposed in the sensor housing to buoy the at least one coil whereby gravitational effects may be neutralized.

Abstract: A technique facilitates geophysical exploration and comprises deploying an optical fiber in a borehole formed in a formation. A seismic signal, e.g. seismic waves, is excited into the formation, and an optical interrogation system is used to obtain data at a plurality of fixed, sampling locations along the optical fiber. The data is processed to determine features in the formation. Based on the processed data, updated sampling locations are selected along the optical fiber to enable further analysis of the features of interest.

Abstract: A technique facilitates geophysical exploration by employing a tool wrapped with an optical fiber. Additionally, an orientation sensor is coupled to the tool and is operable to provide data regarding orientation of the tool. A processing system, which may include an optical interrogation system, cooperates with the optical fiber and with the orientation sensor to obtain acoustic data. For example, the processing system collects tool orientation data and also strain data obtained from a location along the wrapped optical fiber. The strain data results from excitation of an acoustic signal from a suitable acoustic source.

Abstract: A technique facilitates seismic exploration by identifying time differences between clocks employed during the seismic exploration. According to an embodiment, a seismic signal is output from a source and has an incident wave and a reflected wave. The seismic signal is received by at least one receiver which outputs data to a control system. The control system is employed to compare a symmetry of the propagation of the incident wave and the reflected wave. The symmetry data is then used to determine a temporal change of the time base of the at least one receiver.

Abstract: The present invention aims to provide a pattern dimension measurement method for accurately measuring an amount of shrinkage of a pattern that shrinks and an original dimension value before the shrinkage and a charged particle beam apparatus. In order to attain the above-mentioned object, there are proposed a pattern dimension measurement method and a charged particle beam apparatus that are characterized by: forming a thin film on a sample including the pattern after carrying out beam scanning onto a first portion of the pattern; acquiring a first measurement value by scanning a beam onto a region corresponding to the first portion on which the thin film is formed; acquiring a second measurement value by scanning a beam onto a second portion that has identical dimensions as those of the first portion on design data; and finding the amount of shrinkage of the pattern based on subtraction processing of subtracting the first measurement value from the second measurement value.

Abstract: A technique facilitates seismic wave detection with a seismic receiver. The seismic receiver has a tool body, a vibrationally isolated sensor package mounted in the tool body, and a plurality of contact shoes. The contact shoes are mounted around the sensor package in a distribution which enables three-point contact with a surrounding wellbore wall regardless of the azimuthal orientation of the sensor package.

Abstract: A system receives data corresponding to light signals in the plurality of cores, the plurality of cores including a first pair of cores spaced apart laterally along a first direction in the optical fiber, and a second pair of cores spaced apart laterally along a second direction in the optical fiber. The system determines a directional measurement of a dynamic parameter based on the data corresponding to light signals in the plurality of cores, wherein directionality of the directional measurement is indicated by a difference between a response of the first pair of cores to a stimulus and a response of the second pair of cores to the stimulus.

Abstract: A sensor array is positionable in a wellbore penetrating a subterranean formation. The sensor array includes a plurality of seismic sensors disposable about a perimeter of the wellbore and coupleable to a signal measurer with a configuration to provide three component seismic signal measurement within the wellbore. At least two of the seismic sensors are located at different azimuthal angles relative to one another and oriented tangentially to a longitudinal axis of the wellbore so as to receive tangential components of wellbore seismic signals to the exclusion of longitudinal and radial components of the wellbore seismic signals.

Abstract: Methods and apparatus facilitating radial profiling of shear slowness are disclosed. According to some aspects of the invention, acoustic tool bias is accounted for in the calculation of radial profiles. According so some aspects, acoustic tool bias is accounted for by replacing acoustic tool structure with a resonance-impedance model. The resonance-impedance modeling according to principles of the present invention is applicable to vertical, deviated, and horizontal boreholes.

Abstract: Neutrally-buoyant tools for seismic data collection are provided that may range from several hundred meters to several kilometers in length and have integrated sensors which move along with the borehole fluid in response to a passing seismic wave. The disclosure also provides methods of deploying neutrally-buoyant tools, which includes using a tractor, adding a weight or both to the tool in order to overcome the difficulty of lowering a neutrally buoyant tool into a borehole, and optionally occasionally clamping the tool to the borehole to alleviate tension in the tool. This disclosure also provides methods of acquiring seismic data, which involves positioning a neutrally-buoyant tool in a borehole such that the tool is able to move relatively freely along with the borehole fluid in response to a seismic wave passing through the fluid, firing a seismic source, and using the sensors to collect seismic data generated thereby.

Abstract: A sensor array is positionable in a wellbore penetrating a subterranean formation. The sensor array includes a plurality of seismic sensors disposable about a perimeter of the wellbore and coupleable to a signal measurer with a configuration to provide three component seismic signal measurement within the wellbore. At least two of the seismic sensors are located at different azimuthal angles relative to one another and oriented tangentially to a longitudinal axis of the wellbore so as to receive tangential components of wellbore seismic signals to the exclusion of longitudinal and radial components of the wellbore seismic signals.

Abstract: A seismic sesor for a downhole tool positionable in a wellbore penetrating a subterranean formation. The seismic sensor includes a sensor housing, a bobbin supported in the sensor housing along an axis thereof, at least one coil wound about the bobbin (the coil movably supportable within the sensor housing by at least one spring), at least one magnet positionable about the bobbin to generate a magnetic field with the at least one coil whereby seismic vibrations are detectable, and a filler fluid disposed in the sensor housing to buoy the at least one coil whereby gravitational effects may be neutralized.

Abstract: The present invention aims to provide a pattern dimension measurement method for accurately measuring an amount of shrinkage of a pattern that shrinks and an original dimension value before the shrinkage and a charged particle beam apparatus. In order to attain the above-mentioned object, there are proposed a pattern dimension measurement method and a charged particle beam apparatus that are characterized by: forming a thin film on a sample including the pattern after carrying out beam scanning onto a first portion of the pattern; acquiring a first measurement value by scanning a beam onto a region corresponding to the first portion on which the thin film is formed; acquiring a second measurement value by scanning a beam onto a second portion that has identical dimensions as those of the first portion on design data; and finding the amount of shrinkage of the pattern based on subtraction processing of subtracting the first measurement value from the second measurement value.

Abstract: The disclosure provides neutrally-buoyant tools for seismic data collection. The tools may range from several hundred meters to several kilometers in length and have integrated sensors which move along with the borehole fluid in response to a passing seismic wave. The disclosure also provides methods of deploying neutrally-buoyant tools, which includes using a tractor, adding a weight or both to the tool in order to overcome the difficulty of lowering a neutrally buoyant tool into a borehole, and optionally occasionally clamping the tool to the borehole to alleviate tension in the tool. This disclosure also provides methods of acquiring seismic data, which involves positioning a neutrally-buoyant tool in a borehole such that the tool is able to move relatively freely along with the borehole fluid in response to a seismic wave passing through the fluid, firing a seismic source, and using the sensors to collect seismic data generated thereby.