Other

Memsic, Inc.

Quicklogic Corporation

Dong An

Yang Zhao

Chunwei Zhang

Li Sun

Zhenwu Wang

Limeng Zhu

Huixing Jin

Jong-Ki Lee

Duanduan Yang

Ying Wu

Jie Zheng

Haipeng Ding

Longfei Mi

This invention relates to architecture techniques, and more particularly to an assembled double steel-concrete composite shear wall embedded with a damping interlayer, which includes a double steel layer, a double damping interlayer and a concrete layer. The shear wall is formed by bolted bar joints. The double steel layer includes two first steel plates which are arranged along a length of the assembled double steel-concrete composite shear wall in a parallel manner and two second steel plates along a width of the assembled double steel-concrete composite shear wall. The double damping interlayer includes a first damping interlayer which locates between the first steel plates and the concrete layer and a second damping interlayer which surrounds the bolted bar joints and is surrounded by a steel tube.

Assembled double steel-concrete composite shear wall embedded with damping interlayer and method for mounting same

A wrist worn pedometer includes a multiple axis inertial sensor. Signals from each axis of the multiple axis inertial sensor are received and are separately analyzed to determine which axis is producing a stable periodic signal, which is selected as the counting axis, i.e., the axis to be used for counting steps. Additionally, the pedometer determines whether the counting axis is registering arm movement or footsteps. The user's steps are counted based on the detected events, e.g., detected peaks or intervals between peaks, on the signal from the counting axis. One step per detected event is counted if the counting axis is registering footsteps and two steps per detected event are counted if the counting axis is registering arm movement. If the stability of the selected counting axis is lost, another axis is selected as the counting axis if it is producing a stable periodic signal.

Multiple axis wrist worn pedometer

Method and apparatus of integrating a three-axis magnetometer and a three-axis accelerometer to provide attitude and heading, calibrated magnetometer and accelerometer data, and angular rate, while removing sensor error sources over time and temperature and to compensate for hard and soft iron distortions of the Earth magnetic field. Filtered accelerometer data are corrected to account for various error sources. The magnetic heading is calculated from a horizontal magnetic field vector transformed from three dimensional Earth's magnetic field vector by using quasi-static roll and pitch angles from the filtered accelerometer data. A first Kalman filter estimates the state vector, based on the principle that the magnitude of local Earth's magnetic field vector is constant, to form hard and soft iron correction matrices. A second Kalman filter estimates a correction matrix of coupled remaining soft iron and the misalignment of the magnetometer and the accelerometer, as the dot product of local Earth's magnetic field vector and a corrected gravitational acceleration vector, at a quasi-static position, is constant. The three dimensional Earth's magnetic field vector is received by removing the hard and soft irons through the soft iron and hard iron correction matrixes.

Method and apparatus for data fusion of a three-axis magnetometer and three axis accelerometer

An integrated calibration system and process for a three-axis (X, Y, Z) accelerometer estimates Z-axis bias, Z-axis bias drift and determines X, Y, and Z-axes error sources based on measurements taken when the accelerometer is static, i.e., sensing only the earth's gravitational acceleration. Optimal on-the-fly error estimates for the three-axis accelerometer are obtained so that the measurements provided by the three-axis accelerometer remain error-free.

System and method for calibrating a three-axis accelerometer

The present invention provides a cost-effective and power-effective solution to a high performance amplifier design over conventional Class A and Class B/AB amplifiers. Without increasing cost or losing simplification of conventional Class B/AB amplifier configuration, two kinds of unique local feedback loops, which cover the second and third stages and further offer a feedback shifting feature over frequency range, are disclosed to replace the traditional Miller compensation capacitor to suppress dominant distortion, which is usually generated by the two last stages while maintaining stability of the amplifier, through high frequency end. Since the present invention provides key elements of a three-stage amplifier that enable performance improvement in a wide range of circuit design, the present invention has significant commercial values in amplifier circuit industries including audio power amplifiers, IC (integrated circuit) operational amplifiers, ADC (Analog-to-Digital Conversion) and DAC (Digital-to-Analog Conversion) buffers, etc.

Low cost high performance power amplifier utilizing two-stage-included local negative feedback with feedback-shifting technology

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Cupertino, CA, United States of America

Dong An