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Nowadays, the development of GPS (Global Positioning System) technology has become mature, and has begun to develop in the direction of high-precision positioning and navigation. Navigation data such as position, speed, and heading provided by GPS are very important in military or commercial fields. However, in addition to improving the accuracy of positioning, its reliability must also be considered. Therefore, RTK (Real Time Kinematic) differential positioning technology is used to perform real-time error correction and basic inertial components consist of gyroscope, accelerometer, and magnetic compass are used to compensate and improve reliability. In this study, a car is used as a vehicle to experiment the route near the campus. The collected XYZ position coordinate data of the non-difference, differential positioning, and original vehicle are calculated by MATLAB offline operation to obtain $\lambda($longitude), $\Phi$ (latitude), h (height), and the data sensed by integrated inertial elements in the GPS signal shaded roads as auxiliary navigation, and then compare it with the existing and non-differential positioning methods to obtain a more optimized drawing path. The map achieves the compensation effect. In this study, the position of the shaded road is obtained by the second integration of the gyroscopic azimuth change and the heading angle of the magnetic compass through the accelerometer signal. The Extended Kalman Filter algorithm is used as its solution to estimate position, speed and heading of the vehicle in real time to achieve high accuracy and high reliability of real-time positioning and navigation.

Bi0.9Gd0.1FeO3 (BGFO) thin films were deposited on Pt(111)/Ti/SiO2/Si(100) substrates using the sol-gel method. The thin films showed ferromagnetic properties with remnant magnetization (Mr) of 1.2 emu/g and saturation magnetization (Ms) of 5.3 emu/g. It was found that more than one conduction mechanism is involved in the electric field range used in these experiments. 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.

The Y-doped ZnO nanocrystalline films were deposited on the glass substrates by sol-gel method. X-ray diffraction measurements of the films showed the same wurtzite hexagonal structure and preferential orientation along the c-axis. The grain size of the ZnO films was decreased by the doping of Y. Temperature dependence resistivity showed a semiconductor transport behavior for the nanocrystalline films. At low temperature region, the resistivity can be fitted well with the behavior of Mott variable range hopping, σ(T)=σh0 exp[-(T0/T)n] with n=1/4. On the contrary, at high temperature region, the transport mechanism can be fitted with semiconductor behavior by Arrhenius equation, σ(T)=σ0 exp[-(Ea/kT)m] with m=1. The activation energy Ea is increased from 0.47 meV for nondoped ZnO film to 0.83 meV for Zn0.98Y0.02O film obtained from equation. The results demonstrate that the crystallization and the corresponding carrier transport behavior of the Y-doped ZnO films are affected by the doping of Y.

Bi1-xPrxFe0.95Mn0.05O3 (BPFMO) thin films were successfully deposited on Pt(111)/Ti/SiO2/Si(100) substrates by spin coating with a sol-gel technology and rapid thermal annealing. The effects of Pr content on the microstructure, magnetic and multiferroic properties of thin films were investigated. The result of X-ray diffraction analysis shows that the BPFMO thin films have rhombohedral-to-tetragonal R3c→P4mm phase transition at x = 0.15. The Pr doping on the A-site of BiFeO3 could induce the appearance of the spontaneous magnetization and polarization by the phase transition of rhombohedral-to-tetragonal. The BPFMO thin films with x = 0.2 exhibits the maximum remanent magnetization (2Mr) of 0.44 emu/g.

Well-defined ZnO and ZnO: La nanorods have been successfully fabricated by a low temperature hyderthermal process. The XRD patterns of both compositions with single diffraction peak (002) show the same wurtzite hexagonal structure. The radius of ZnO: La nanorods observed by FE-SEM is smaller than that of pure ZnO indicating the inhibition of growth rate by the doping of La. Photoluminescence spectra show an enhancement of the luminescence intensity in green-yellow region by the dopant La. Ferromagnetism is observed from the results of magnetization measurement. The increase of the saturation magnetization reveals an association with the increase of oxygen vacancies induced by the doping of the La in the nanorods.

Bi 4 Ti 2.96 Ta 0.04 O 12 (BTTO) thin films were deposited on Pt(111)/Ti/SiO 2 /Si(100) substrates by sol–gel method. The effects of Ta-substitution and annealing temperature (500–800 °C) on the microstructure and ferroelectric properties of Bi 4 Ti 3 O 12 thin films were investigated. X-Ray diffraction analysis reveals that the intensities of (117) peaks are realitively broad and weak at annealing temperatures smaller than 700 °C. With the increase of annealing temperature from 500 °C to 800 °C, the grain size of BTTO thin films increases. The BTTO thin films annealed at 700 °C exhibit the highest remanent polarization (2P r ) of 40 μC/cm2 and lowest coercive field (2E c ) of 120 kV/cm. It is obvious that the measured 2P r of the BTTO thin film is larger than that of Bi 4 Ti 3 O 12 thin films (2P r =25 μC/cm2) The improved ferroelectric properties can be attributed to the substitution of Ta5+ to Ti4+ in Bi 4 Ti 3 O 12 assisted the elimination of defects such as oxygen vacancy and vacancy complexes.

Ferroelectric polymer/ceramic structure thin films were fabricated on Pt/SiO/sub 2//Si substrates using a sol-gel method. The bilayer thin film was composed of polar /spl beta/-phase poly(vinylidene fluoride) (PVDF) and 1 /spl mu/m thickness of polycrystalline lead titanate (PbTiO/sub 3/) thin film. By changing the concentrations of PVDF solutions (0.6/spl sim/1.0 M), various thickness of PVDF thin films (50-580 nm) were obtained, and the effects of various processing parameters on the characteristics of PVDF/PbTiO/sub 3/ thin films were studied. The characteristic of the /spl beta/ phase at infrared spectrum of 511 and 840 cm/sup -1/ can be observed in PVDF film crystallized at 65/spl deg/C for 2 h. With the increase of the PVDF thickness of the PVDF/PbTiO/sub 3/ films, the relative dielectric constant (/spl epsi//sub r/) decreased from 63 to 20 and the leakage current density (J) also decreased from 1.54 /spl times/ 10/sup -6/ to 3.86 /spl times/ 10/sup -7/ A/cm/sup 2/.

The novel pyroelectric infrared (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(/spl sim/1 /spl mu/m) heated at 700/spl deg/C for 1 h and the /spl beta/-phase PVDF film crystallized at 65/spl deg/C for 2 h. The effects of PVDF thin film thickness (100/spl sim/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 /spl times/ 10/sup -7/ A/cm/sup 2/ to 3.86 /spl times/ 10/sup -7/ A/cm/sup 2/. The specific detectivity (D*) measured at 100 Hz decreased from 2.72 /spl times/ 10/sup -7/ cm/spl middot/Hz/sup 1/2//W for detector without PVDF to 1.71 /spl times/ 10/sup -7/ cm/spl middot/Hz/sup 1/2//W for detector with PVDF thickness of 580 nm. By optimizing the ratio of the specific detectivity (D*) to leakage current, D*/J, the detector with PVDF thickness of 295 nm exhibits the best performance.

La-modified lead titanate (PLT) thin films were deposited on Pt/SiO/sub 2//Si substrates by spin coating with sol-gel processing. 1,3-propandiol was used as solvent to minimize the number of cycles of spin coating and drying processes to obtain the desired thickness of high quality thin film. The randomly oriented PLT thin film exhibits a relatively small dielectric constant and a large pyroelectric coefficient without poling treatment. Pyroelectric infrared (IR) detectors have been fabricated without the back side etching process The pyroelectric characteristics of point detectors with various La contents as a function of modulation frequency are compared. It was found that the PLT(10) detector has a large voltage responsivity of 3330 (V/W) at 20 Hz. The specific detectivity (D*) at 100 Hz is 6.2/spl times/10/sup 7/ cmHz/sup / 1/2 //W. The results showed that Pb/sub 1-x/La/sub x/Ti/sub 1-x/4/O/sub 3/ thin film with x=0.10 [PLT(10)] was most suitable for use as a pyroelectric IR detector.

Calcium-modified lead titanate (PCT) thin film pyroelectric infrared (IR) detectors were fabricated on Pt(111)/SiO/sub 2//Si[100] substrates using a diol-based sol-gel process. The randomly oriented PCT thin film, which has not undergone the poling treatment, exhibits a relatively small dielectric constant and a large pyroelectric coefficient. The pyroelectric properties of PCT thin film point detectors with various Ca contents on modulation frequency are measured and compared. The optimized composition of PCT thin film IR detectors was found to be the PCT(25), which exhibits a large voltage responsivity of 4533 (V/W) at 20 Hz and a specific detectivity (D*) of 6.45 /spl times/ 10/sup 7/ cmHz/sup 1/2//W at 100 Hz The results show that Pb/sub 1-x/Ca/sub x/TiO/sub 3/ thin film with x = 0.25 [PCT(25)] was most suitable for application to the pyroelectric thin film IR detector.