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At present, various applications have a high demand for navigation systems. With the example of self-driving cars, the navigation system has to provide pinpoint accuracy for positioning. Inertial navigation system (INS) and global positioning system (GPS) are some of the common ways to navigate. However, these two systems have the disadvantages of continuity, cumulative error, divergence over time, and reliability. A solution based on the extended Kalman filter (EKF) and long- and short-term memory (LSTM) is proposed in this study to correct the divergence due to cumulative errors in INS. It has been proven effective by a number of studies to combine a Kalman filter with GPS and INS data. However, there are still issues in the integration of the Kalman filter with INS/GPS, such as random error model, noise resistance, and observability of inertial sensors. The proposed system is designed to incorporate deep learning to comb through long-, medium-, and short-term memories as well as predict INS and GPS errors using recurrent neural network (RNN), as LSTM is used to learn INS errors while the GPS is working well and to predict GPS errors when GPS signals are lost. Unlike the traditional way of learning, LSTM contains time variants. To verify the accuracy of the proposed design, the EKF is introduced as a means to compare with LSTM. EKF is very suitable for more flexible coordination between INS and GPS, so EKF is used for deep learning comparison with LSTM for prediction and control in a nonlinear environment. Then, the LSTM deep learning is used to correct the predictions. This computation reduces the errors in position and speed. Finally, an emulation model developed in MATLAB is used to simulate the INS-GPS integrated system error compensation model. The experiment results indicate that the errors in parameters are the smallest with the integration of LSTM in INS and GPS, thus providing the effects of error correction and compensation. [ABSTRACT FROM AUTHOR]

Bipolar resistive switching properties and endurance switching behavior of the neodymium oxide (Nd2O3) thin films resistive random access memory (RRAM) devices for a high resistive status/low resistive status (HRS/LRS) using a low temperature supercritical carbon dioxide fluid (SCF) improvement post-treatment process were investigated. Electrical and physical properties improvement of Nd2O3 thin films were measured by X-ray diffraction (XRD), scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS) and current versus voltage (I-V) measurement. The metal-like behavior of ohmic conduction mechanism and metallic cluster reaction of hopping conduction mechanism in initial metallic filament path forming process of the SCF-treated thin films RRAM devices was assumed and discussed. Finally, the electrical conduction mechanism of the thin films RRAM derives for set/reset was also discussed and verified in filament path physical model. [ABSTRACT FROM AUTHOR]

Bi0.8Pr0.2Fe0.95Mn0.05O3/Bi3.96Gd0.04Ti2.95W0.05O12 (BPFMO/BGTWO) bilayer thin films with Multiferroic/Ferroelectric (MF/FE) structures were deposited onto Pt(111)/Ti/SiO2/Si(100) substrates by using the sol-gel method with rapid thermal annealing. The BPFMO/BGTWO thin films exhibited well-saturated ferromagnetic and ferroelectric hysteresis loops because of the electro-magnetic coupling induced by the MF/FE structure. The remnant magnetization (2Mr) and remnant polarization (2Pr) were 4.6 emu/cm3 and 62 μC/cm², respectively. Moreover, the bipolar I-V switching curves of BPFMO/BGTWO bilayer thin films resistive random access memory (RRAM) devices were discussed, and investigated for LRS/HRS. [ABSTRACT FROM AUTHOR]

LiTaO3 thin films were deposited onto Pt(111)/SiO2/Si(1000) substrates using the sol-gel method and rapid thermal annealed in an oxygen atmosphere with a heating rate of 600˜3000°C/min. The leakage currents of the lithium tantalite thin films were measured and its leakage current mechanism was investigated. It was found that the leakage current was affected by the interface between the Pt electrode and LiTaO3 thin films. In the low electric field region, the leakage current was controlled by Poole-Frenkel emission. On the other hand, the mechanism can be explained by Schottky emission from the Pt electrode in the high field region. [ABSTRACT FROM AUTHOR]

The LiTaO3 thin films were prepared by a diol-based sol-gel method and crystallized by conventional and RTA processes. Based on the results, the c-axis orientation of the films crystallized by the RTA process presented better crystallization than those crystallized in a conventional furnace. The remanent polarization (P...) and the coercive field (Ec) of the films crystallized in a conventional furnace were about 2.4 µC/cm2 and 87 kV/cm. On the contrary, for LiTaO3 films crystallized by the RTA method, the remanent polarization (P...) and the coercive field (Ec) were about 10.7 µC/cm2 and 45kV/cm, respectively. [ABSTRACT FROM AUTHOR]

The novel pyroelectric IR detectors have been fabricated using the Polyvinylidene Fluoride (PVDF)/Lead Titanate (PT) pyroelectric bilayer thin films, which were deposited onto Pt(111)/SiO[sub 2]/Si(100) substrates by a sol-gel process. The ceramic/polymer structure was constructed of the randomly oriented polycrystalline PT film (∼1 µm) heated at 700°C for 1 h and the β-phase PVDF film crystallized at 65°C for 2 h. The effects of PVDF thin film thickness (100 ∼ 580 nm) on the pyroelectric response of IR detectors were studied. The results show that the depositions of PVDF thin films onto the PT films will cause the leakage current (J) of the detectors decrease from 6.37 × 10[sup -7] A/cm² to 3.86 × 10[sup -7] A/cm². The specific detectivity (D[sup *]) measured at 100 Hz decreased from 2.72 × 10[sup 7] cm. Hz[sup ½]/W for detector without PVDF to 1.71 × 10[sup 7] cm. Hz[sup ½]/W for detector with PVDF thickness of 580 nm. By optimizing the ratio of the specific detectivity (D[sup *]) to leakage current, D[sup *]/J, the detector with PVDF thickness of 295 nm exhibits the best performance. [ABSTRACT FROM AUTHOR]

Four p–i–n GaInP solar cells were grown by metal organic chemical vapor deposition (MOCVD) with different intrinsic layer thicknesses from 0.25 to 1 µm. A series of optical measurements, including electroreflectance (ER), photoluminescence (PL), electric luminescence (EL), and photocurrent (PC) measurements, have been performed to study the built-in electric field effect and to determine the suitable thickness of an intrinsic layer. The PL and EL spectra reflected the crystal quality of the GaInP layers. Furthermore, from the obtained ER spectrum, the built-in electric field in the intrinsic layer can be revealed. From the PC spectra under various bias voltages, the effect of built-in electric fields on the collection of photogenerated carriers has been studied. [ABSTRACT FROM AUTHOR]