A time-delayed enlarged three-dimensional (3D) gravitational wave detection system may include a three optical fibers along three axes (X, Y, and Z-axis); and a laser signal source operatively linked with the three optical fibers; wherein structures of the three optical fibers are identical, and are adapted to pick up space/lengths changed caused by gravitational waves. And, the laser signal source includes a narrow linewidth laser to generate laser lights, an electro-optic modulator (EOM) connected with the narrow linewidth laser to modulate the phase of laser light, and a RF signal source connected to the EOM to provide ultra-stable RF signal to the EOM. In one embodiment, said narrow linewidth laser is adapted for carrying the ultra-stable RF signal, and said ultra-stable RF source is used for detecting length changes caused by the gravitational waves.

A time-delayed enlarged three-dimensional (3D) gravitational wave detection system may include a three optical fibers along three axes (X, Y, and Z-axis); and a laser signal source operatively linked with the three optical fibers; wherein structures of the three optical fibers are identical, and are adapted to pick up space/lengths changed caused by gravitational waves. And, the laser signal source includes a narrow linewidth laser to generate laser lights, an electro-optic modulator (EOM) connected with the narrow linewidth laser to modulate the phase of laser light, and a RF signal source connected to the EOM to provide ultra-stable RF signal to the EOM. In one embodiment, said narrow linewidth laser is adapted for carrying the ultra-stable RF signal, and said ultra-stable RF source is used for detecting length changes caused by the gravitational waves.

A wireless lighting device for vehicle accessories includes a signal transmitter and an encapsulated light board. The light board includes a unitary baseplate, a backlight module, a power module, and a top cover. The backlight module including a circuit board, light emitting elements, a transceiver, and a control module configured to turn the light emitting elements on and off according to the detected signal. The power module including a battery and a conductive strip configured to electrically connect the battery to the circuit board. The top cover configured to be irreversibly sealed to the baseplate with a customizable light permeable region covering the light elements. The transmitter configured to be installed on a door or a frame of a vehicle, and the light board configured to be installed in a vehicle accessory. The wireless lighting device having at least a ten year operational life without replacement of the batteries therein.

A wireless lighting device for vehicle accessories includes a signal transmitter and an encapsulated light board. The light board includes a unitary baseplate, a backlight module, a power module, and a top cover. The backlight module including a circuit board, light emitting elements, a transceiver, and a control module configured to turn the light emitting elements on and off according to the detected signal. The power module including a battery and a conductive strip configured to electrically connect the battery to the circuit board. The top cover configured to be irreversibly sealed to the baseplate with a customizable light permeable region covering the light elements. The transmitter configured to be installed on a door or a frame of a vehicle, and the light board configured to be installed in a vehicle accessory. The wireless lighting device having at least a ten year operational life without replacement of the batteries therein.

A method and system for in-sit calibration of a gravimeter. A method may comprise disposing a downhole tool in a borehole, wherein the downhole tool comprises the gravimeter attached to a linear actuator, recording a first set of measurements with the gravimeter while the linear actuator is stationary, activating the linear actuator, recording a second set of measurements with the gravimeter, and calibrating the gravimeter based on the first and second set of recorded measurements. A system may comprise a downhole tool, a conveyance, and an information handling system. The downhole tool may further comprise a hanger, a sonde, connected to the hanger, a linear actuator, connected to the hanger, and a shaft, connected to the linear actuator. The downhole tool may further comprise a linkage, connected to the shaft, a package, connected to the linkage, and a gravimeter, disposed in the package.

A method and system for in-sit calibration of a gravimeter. A method may comprise disposing a downhole tool in a borehole, wherein the downhole tool comprises the gravimeter attached to a linear actuator, recording a first set of measurements with the gravimeter while the linear actuator is stationary, activating the linear actuator, recording a second set of measurements with the gravimeter, and calibrating the gravimeter based on the first and second set of recorded measurements. A system may comprise a downhole tool, a conveyance, and an information handling system. The downhole tool may further comprise a hanger, a sonde, connected to the hanger, a linear actuator, connected to the hanger, and a shaft, connected to the linear actuator. The downhole tool may further comprise a linkage, connected to the shaft, a package, connected to the linkage, and a gravimeter, disposed in the package.

The present disclosure discloses a submarine position detection method based on extreme points of gravity gradients. A space rectangular coordinate system is established by taking a centroid of the middle cylindrical portion as a coordinate origin, a direction pointing to a bow is taken as a forward direction of the X axis, a direction pointing to a port is taken as a forward direction of the Y direction, and a vertical upward direction is taken as a forward direction of the Z axis. The detection method includes steps of: determining a horizontal position of a submarine, i.e., coordinates (X, Y), according to a position of a central extreme point and a central position between extreme points of non-diagonal components of a gradient tensor; and determining a functional relation between a depth and the extreme points of gravity gradients by using the submarine model.

The present disclosure discloses a submarine position detection method based on extreme points of gravity gradients. A space rectangular coordinate system is established by taking a centroid of the middle cylindrical portion as a coordinate origin, a direction pointing to a bow is taken as a forward direction of the X axis, a direction pointing to a port is taken as a forward direction of the Y direction, and a vertical upward direction is taken as a forward direction of the Z axis. The detection method includes steps of: determining a horizontal position of a submarine, i.e., coordinates (X, Y), according to a position of a central extreme point and a central position between extreme points of non-diagonal components of a gradient tensor; and determining a functional relation between a depth and the extreme points of gravity gradients by using the submarine model.

A motion detecting device includes an accelerometer configured to generate gravitational acceleration readings associated respectively with consecutive time segments, an angular acceleration sensor and configured to generate angular acceleration readings, and a processor operable in one of a standby mode and an active mode. When operated in the standby mode, the processor activates the accelerometer, deactivates the angular acceleration sensor, and determines whether the user is in a substantial moving state. When determined that the user is in the substantial moving state, the processor switches to the active mode to activate both the accelerometer and said angular acceleration sensor, in order to determine the motion of the user.

A motion detecting device includes an accelerometer configured to generate gravitational acceleration readings associated respectively with consecutive time segments, an angular acceleration sensor and configured to generate angular acceleration readings, and a processor operable in one of a standby mode and an active mode. When operated in the standby mode, the processor activates the accelerometer, deactivates the angular acceleration sensor, and determines whether the user is in a substantial moving state. When determined that the user is in the substantial moving state, the processor switches to the active mode to activate both the accelerometer and said angular acceleration sensor, in order to determine the motion of the user.