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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.

The luminescent down-shifting (LDS) effect of a colloidal quantum dot layer on a dual junction solar cell is explored and analyzed. A 5.47% enhancement of power conversion efficiency is recorded when green quantum dots are dispersed on device surface. The surface reflectance spectra before and after the quantum dot dispenses are necessary to decouple the different mechanisms between antireflective and LDS effects. A further deduction of formulation on the dual-junction device with antireflection and LDS effect is presented and as high as 44.6% of short-circuit current increase in the green quantum dot case can be attributed to the LDS effect according to our calculation.

Millimeter wave (mmWave) techniques have attracted much attention in recent years owing to features such as substantial bandwidth for communication, and it has applications in radar systems and location applications. To compensate for the severe path loss in mmWave bands, beamforming techniques with a massive antenna array are usually employed to provide high directivity. However, the resulting high-gain and narrow pencil beam make the beam alignment costlier and much more difficult. Hence, conducting beam alignment with a low overhead becomes critical. Herein, we propose a promising solution that does not require channel knowledge and treats the beam selection as an image reconstruction problem; thus, deep neural networks can be employed to operate the beam domain image reconstruction. This approach can be divided into two stages: off-line training and on- line prediction. The overhead of the on-line beam selection can be significantly reduced via off- line Eigen-beam extraction without degrading the beamforming performance. Simulations are conducted to confirm the performance of the proposed framework in scalability and robustness.

In this work, we discuss the feasibility of two color photons for boosting up the short-circuit current and power conversion efficiency in tandem solar cell. One of them is by luminescent down-shifting (LDS) effect, and the other one is the infrared light emitting diode at 820nm. The CdZnSeS/ZnS quantum dots are used in this study. It can convert ultra-violet photons to visible ones which could be efficiently transformed into electron-hole pairs. The infrared-radiation LED can increase photo-generated carriers of the bottom GaAs solar cell. Finally, short-circuit current would significantly increase from 10.46 mA/cm2 to 13.81 mA/cm2, and power conversion efficiency increase from 19.89 to 25.22%. This result shows the possible double-LDS effect for solar cell enhancement in the future.

Millimeter wave (mmWave) communications are a mainstream technology of the fifth generation (5G) systems. Beamforming plays an important role in mmWave communications thanks to its ability to provide beamforming gain to compensate the high propagation and penetration loss in the mmWave bands. To reduce the overhead (time and power consumption) in mmWave beamforming, AI techniques can be employed to enhance beam selection efficiency. We here propose a method that uses a machine learning algorithm to learn the features of mmWave channels by off-line training to assist online beam selection so that the overhead is significantly reduced without degrading the beamforming performance. The proposed framework involves codebook-based beam selection and local learning-based clustering algorithm with feature selection (LLC-fs). Simulation results are conducted to confirm the performance of the proposed method in three aspects, scalability, robustness and compatibility.

In this work, we demonstrate the the enhancement of two type hybrid QD dual-junction solar cell. The green QD520 sample, shows better performance than blue QD450 sample in current density and power conversion efficiency. The enhancement of short-circuit current and power conversion efficiency for green QD450 sample are 4.43% and 3.77% and the blue QD520 samples are 9.44% and 5.78%. For short wavelength, the enhancement can mainly be attributed to the photon downshift effect and antireflection, for long wavelength, it only the antireflection effect.

This paper discusses a new online tool for online gamers to share networking performance results and to produce aggregate networking performance reports generated from the data reported by all users. It is necessary to improve the quality of service and make online games faster. This will help improve latency sensitive game data collection. It will help to improve gaming performance through the global network of servers, optimizing the game connection from end to end. A Web API was developed to receive data in the form of a HTTP post from WTFast clients while they are playing their games. A data generator was also built to simulate thousands of concurrent users posting data to the web API. The web API stores the data in a Elasticsearch database. A web interface was built for WTFast clients to view their historical network data and to share it on forums or social media. The web interface shows a graph of their network performance with and without using the GPN R . The complete system is anticipated to need to handle approximately 400,000 concurrent users sending network data every 2 seconds.

Three buffer layers, that included 2-step, step-graded, and linear-graded layers, were designed to improve the performance of In 0.16 Ga 0.84 As solar cell. The In 016 Ga 084 As solar cells fabricated on these three buffer layers were denoted as 2S-cell, S-cell, and L-cell, respectively. The efficiencies of these three devices were 9.8%, 14.4%, and 16.3%, respectively. Obviously, the linear-graded buffer layer is most helpful to enhance the efficiency of In0.16Ga0.84As solar cell. Additionally, the front electrode angle of In 0.16 Ga 0.84 As solar cell was varied from 0° to 90°. When the angles were fixed at 0° and 90°, the devices possessed higher efficiencies of 16.3% and 16.6%, respectively.

Through the epitaxial lift-off (ELO) process using the HF solutions mixed with hydrophilic substances consisting of acetone (ACE), isopropanol (IPA), and methanol (MA), the separation rate for the GaAs substrate and the III–V solar cell can be improved significantly. Especially for the use of HF:ACE etchant, a extremely high lateral etching rate (14.3 µm/min) of the AlAs sacrificial layer can be achieved, as compared with that employing the pure HF etchant (3.6 µm/min). In addition, by conducting the ELO technique, the GaAs substrate was reused for four times, indicating its high potential for the reusable applications.

A new enhanced displacement-current triggering by adding floating P+ diffusions at each source finger edge for the HV LDNMOSFET is proposed. Unlike the conventional substrate-triggered ESD protection technologies, it is very easy to implement the scheme by the layout without any special circuit and additional component. With a total width of 1600 μm, the HBM/ MM ESD performance improvements from 1.5 kV/ 150 V to 5.5 kV/ 450 V are achieved.

From the experimental measurements, the dominant charge source for a packaged IC chip during a charged-device model (CDM) ESD event is the capacitor between the die-attach plate and the metal bus line, C SUB . By adding a bonding wire between the die-attach plate and the Vss pin, a parallel inductor to the C SUB can be created. The CDM-robustness for the packaged IC chip is significantly improved because of this parallel LC resonance circuit.

We propose a novel nLDMOS structure and a design concept in BCD technology with the best-in-class performance. The drift profile is optimized and the multi-oxide in the drift region is adopted to approach the RESURF limit of on-resistance vs. BVdss characteristic (i.e., 36V DMOS has a Ron_sp of 20mohm-mm2 with a BVdss of 50V; 45V DMOS has a Ron_sp of 28mohm-mm2 with a BVdss of 65V). Moreover, this modification requires merely three extra masks in the Non-Epitaxy LV process to achieve this improvement. Therefore it is not only a high performance but also a low cost solution.

As cloud computing platform provides computing power as utilities, it is important to develop a mechanism to adaptively adjust the resources needed for handling cloud service. In this paper, a computing resource minimization framework for cloud-based surveillance video analysis systems is proposed. Videos streams are divided into clips and multiple processing nodes are used to handle clips. While the quality-of-service (QoS) is maintained, the proposed framework dynamically adjusts the number of processing nodes based on a proposed content-aware workload estimation mechanism. Experimental results show that the proposed mechanism successfully predicts the variability of system workload while QoS is maintained and outperforms other mechanisms in terms of average virtual machine (VM) quantity and job failure ratio.

Despite the rapid development of wireless communication and broadband applications for multimedia service, the 2 Mbps downlink data rate of the present 3G communication system cannot satisfy demand for a fast and high quality packet data service. The use of the HSDPA (High Speed Downlink Packet Access) air interface can upgrade the downlink packet data rate by 10.7~14.4 Mbps. This paper presents a mobile backhaul planning process and proposes a network reliability analysis of the ROADM design for next generation transport network. The term mobile backhaul refers to the fixed wire-line and/or wireless interconnections of mobile service base stations, and their connection to the core telecommunications network. We examine the NGSDH+OXC systems in the fixed wire-line for the HSDPA offload. The traffic statistics of the cell and the HSDPA area's measurement results of its communication quality show that the planning is successful and satisfy the QoS standard.

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.

A new kind of ESD failure mechanism is found in the UHV 700V LDNMOS during the HBM ESD zapping event. The device is damaged by its own charges and board stored charges, not damaged by the HBM stress current. The device junction capacitor and test-board capacitor store the charges from the ESD tester before the avalanche breakdown occurring. After the avalanche breakdown, the two capacitors discharge the stored charges to give the additional currents to stress the device. This phenomenon is called the charged-capacitor model (CCM) [1].

Recommender systems are emergent to help overcome the information overload challenges by providing personalized suggestion based on users’ preference. To achieve this goal, most recommender systems utilize Collaborative Filtering (CF) technique. Multiple Criteria Decision Analysis (MCDA) is a discipline aimed at supporting decision makers to make an optimal selection in an environment of conflicting and competing criteria. In the paper, we propose a mechanism for integrating MCDA into the CF process for multiple criteria recommendations. The proposed system consists of two main parts. Firstly, the weight of each user toward each feature is computed by using multiple linear regression. The feature weight is then incorporated into the collaborative filtering process to provide recommendations. The experimental results showed that the proposed approach outperformed the single criterion CF method.

Multi-hop extension is fulfilled by constructing child or neighbor piconets in IEEE 802.15.3 standard. This approach does not consider the multi-channel capability in the physical layer. The scalability of the design is limited. This paper discusses how to construct a multi-piconet network and improve the performance of UWB multi-hop WPANs in the existing 802.15.3 standard based on a bridge device (BDEV). BDEV is a member of all interconnected piconets. The coverage extension by BDEVs follows the 802.15.3 standard and it takes benefit from the space reuse. BDEV with only one network interface is cheap and simple to extend a flexible construction of ad hoc networking of WPANs. Furthermore, a distributed scheduling scheme on BDEV is proposed to improve the delay performance. Through detailed simulations, the proposed distributed BDEV scheduling scheme are shown to be effective to extend network coverage.

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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.

For the velocity-following problem of an unmanned land vehicle, the classical PD control law is shown to be robust with respect to highly nonlinear dynamics by properly choosing the control gains. The tracking error system is shown to be uniformly and ultimately bounded. The choices for the gains depend only on the bound of the nonlinear dynamics. Even though the coefficients of the polynomial bounding function are unknown, the robustness PD law can be guaranteed by simply increasing the gains that satisfy certain inequalities. Experiment results are presented to validate the conclusions. >

In this paper, the authors explore the accuracy of performance simulation program for trains in actual operation. They first study the details of push-pull type trains running in speed control mode to obtain the block diagram of train dynamics. Important features in speed control function such as dead-band and acceleration rate limits are included and function blocks are developed to represent actual behavior. Then they use MATLAB/SIMULINK(R) to implement the simulation program in a straightforward manner. Field Measurements of important variables like speed demand, train speed, traction demand and line voltage were taken to validate the simulation results.

In this paper, we present an RTL design-space exploration method for high-level applications. We formulate the RTL design-space exploration into a performance-driven module selection problem. We devise a dynamic programming algorithm to solve the problem. We present an exploration flow by integrating commercial synthesis and layout tools with our proposed method. Experimental results have demonstrated that generating an AT-curve for all modules is the most time consuming task in the design-space exploration process. Using the proposed 3-point AT projection approach, our method can achieve on an average of 80% speed-up in run time and 90% accuracy in design estimation.

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.

Converting an HDL-based design into an emulation system for design verification is an extremely complex and time-consuming task. One possible solution to improve productivity is an effective emulation-based design methodology that exploits the modularity of designs. This paper develops and explores such a methodology. We present a multi-level synthesis method which is able to establish a direct link between High-level Descriptive Language (HDL) constructs and corresponding circuit designs. This feature greatly facilitates HDL debugging capabilities such that when bugs are detected in sub-netlists, links allow the corresponding HDL source code to be easily recognized. This powerful feature greatly reduces design debugging time. Experimental results on a set of industrial designs are reported in order to demonstrate the effectiveness of the proposed synthesis methodology.