Facial component and landmark detection have many applications in many facial analysis tasks. In this paper, a semisupervised method for this task is proposed to detect facial components and landmarks. Different from other facial detectors algorithms, our model without extra input solve the occlusion problem by detecting the visible facial components. Firstly, we propose a data augmentation method based on the Deep Convolutional Generative Adversarial Network to generate a large amount of semi-supervised training data. Then, a semi-supervised learning model based on Region-based CNN is responsible for multi-task facial component and landmark detection by training on the generated semi-supervised training data. During training, facial component regions and landmarks are used as supervised training data, while unsupervised training data only contains component bounding box. Experimental results illustrate that the proposed model can handle multi-task facial detection, and outperforms the state-of-the-art algorithms.
KEYWORDS: Sensors, Silicon, Electrodes, Boron, Resonators, Signal to noise ratio, Finite element methods, Sensor performance, Packaging, Microelectromechanical systems
To improve the performance of the micro-machined resonant pressure sensor and simplify its fabrication process, a
novel structure is proposed in which the boron diffused silicon (up to 15um thickness) and the bulk silicon are used as
the resonant beam and pressure membrane respectively. The structural parameters were optimized through FEM to
achieve the better sensitivity, and the relationships between the structural parameters and the sensitivity were
established. Moreover, the fabrication processes were discussed to increase the product rate and the pressure sensor with
the optimal structural parameters was fabricated by the bulk silicon MEMS processes. In order to enhance the signal of
the sensor and make the closed-looped control of the sensor easily, electromagnetic excitation and detection was applied.
However there is so high noise coming from the distributing capacitances between the diffused silicon layer and
electrodes that reduce the signal to noise ratio of the sensor. Through the analysis of the micro-structure of the sensor,
the asymmetrical excitation circuit was used to reduce the noise and then the detection circuit was designed for this
sensor. The resonator of the sensor was packaged in the low vacuum condition so that the high quality factor (Q) with
about 10000 can be achieved. Experimental tests were carried out for the sensor over the range of -80kPa to 100kPa, the
results show that the sensitivity of the sensor is about 20kHz/100kPa, the sensitivity is 0.01%F.S. and the nonlinearity is
about 1.8%.
A novel resonant pressure sensor structure is proposed to achieve better performance in quality factor (Q) and output
stability. Diffused silicon (15um) is used for the resonator, thus the resonator and the pressure diaphragm can be
fabricated on the same silicon substrate without bonding. A differential detection tri-resonator structure is adopted to
reduce the output drift and increase the sensitivity. To optimize the structure, a simplified 2-D model is set up for the
theoretical analysis. In addition, 3-D models of the 'H' style beam and the entire structure which is composed of a
diaphragm and three groups of beam respectively doubly supported by the anchors are constructed for the ansys-FEA
simulation. Through the theoretical analysis and the simulation, the structure parameters (beam length, beam thickness,
diaphragm thickness etc) are optimized. The natural frequency of the optimized model is 86.7 KHz, and the sensitivity is
19 KHz per 0.1MPa. The sensor is fabricated with the optimized parameters. The test experiments show that the results
basically correspond with the simulation results except the effect of the wet etching in the fabrication process. The
quality factor is 10000 in low vacuum, and the resolution is 1/10000.
A novel structure of micro-machined vibrating ring gyroscope (MVRG) with electromagnetic excitation and detection is
proposed, which consists of a ring and eight pairs of symmetric crab-leg suspension springs. The whole structure is
mirror-symmetric and centrosymmetric, providing the possibility to realize good mode-matching when the temperature
changes or acceleration shocks. The sensitivity of the MVRG is analyzed in detail, and the stability of the structure over
temperature and acceleration loads is analyzed using finite element analysis. The prototype of vibrating ring gyroscope is
successfully fabricated through bulk silicon processes which adopt only one silicon wafer without bonding process. The
gyroscope chip is assembled with SmCo permanent magnet and packaged in a metal case. The design of self-oscillation
closed-loop circuit is presented. FEA simulations show that the performance of the MVRG is stable over temperature
and acceleration loads and the structure can withstand shock loads up to 10000g without any special protection. Test
results show that the sensitivity of the MVRG is 8.9mv/°/s and the resolution is 0.05°/s with nonlinearity about 0.23% over a range of ±200°/sec.
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