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Recent advances in pedestrian navigation, a branch of wearable body area networks (WBAN), facilitate people's lives to help them get access to location-based services (LBS) at anywhere easily. This paper proposes a pedestrian dead-reckoning (PDR) algorithm to track the trajectory of the person using foot-mounted inertial measurement unit (IMU) and the estimation of the foot orientation with extended...
In whole body PET scanners, extending the axial field of view (AFOV) can significantly increases the sensitivity. However, image axial resolution, which is an essential criterion in whole-body PET, may be especially affected by the depth of interaction (DOI) as the AFOV increases. In this paper, we use Monte Carlo simulations to find, in a long axial-FOV PET how DOI information affects the axial resolution...
Recently DOI detection technologies have been rapidly developed for pre-clinical and clinical PET systems. Lack of DOI detection capability will result in serious LOR location deviation and image resolution degradation due to the detector parallax effect. Based on theoretically analyzing the probability distribution function of the DOI information, this study proposed four analytical DOI estimation...
In this study we proposed a novel design of the stationary multi-pinhole dedicated cardiac SPECT based on clinical dual-head scanner with high sensitivity and low cost for nuclear medicine myocardial perfusion imaging.
In previous work, we have developed a cost-effective small-animal SPECT imaging system by adding a multi-pinhole cylinder collimator into an animal PET scanner. To achieve high-quality reconstructed SPECT image, accurate geometrical calibration of the collimator is critical. The pinhole position in PET-scanner's coordinate system (PSC) could be factorized into two parts: pinhole position in collimator's...
As a specially designed mechanism, cam is usually be used in many high-speed structures and mechanisms. Diverse geometric cam counters support for diverse motion applications, including the displacement, the velocity and the acceleration. This paper proposes a design of a high-speed cam which can be applied in a quick-action-based four bar linkage system. This variable high-speed cam is design by...
For decades, popular culture has been enthralled with the possibility of robots that act and look like human. Walking, as one of the most important features of human, needs to be well implemented by humanoid robots. In order to perform stable robot gait, it is necessary to control the position of the Zero Moment Point (ZMP) of the robot. To calculate the ZMP, forces and moments under robot feet are...
This paper presents a natural corners-based two-dimensional (2D) Simultaneous Localization and Mapping (SLAM) with a robust data association algorithm in a real unknown environment. The corners are extracted from raw laser sensor data and chosen as landmarks for correcting the pose of mobile robot and building the map. In the proposed data association method, the extracted corners in every step are...
In this paper, titanium-doped zinc oxide (TZO) films were prepared by radio frequency (RF) sputtering at different RF powers acting as the channel layers of thin film transistors (TFTs). Through the analysis of scanning electron microscope (SEM), X-Ray diffraction (XRD) and transfer characteristics, we studied the effects of RF power on properties of TZO films and TZO-based TFTs and obtained optimum...
A digital one-cycle control strategy combined with the Quasi Proportional Resonant (QPR) controller is applied to the three-phase grid-connected inverter with LCL filter in this paper. The control system contains dual loops with inner loop of capacitive current and outer loop of net current. Instead of conventional SPWM modulation method, one-cycle control for the inner loop has functions of control...
As mobile crowd sensing techniques are steering many smart-city applications, an incentive scheme that motivates the crowd to actively participate becomes a key to the success of such city-scale applications. This paper presents a crowd sensing WiFi advisory system called WiFiScout, which helps smartphone users to find good quality WiFi hotspots. The quality information is defined in terms of user...
This paper aims at improving the performances of Titanium-doped Zinc-oxide (TZO) Thin-Film-Transistors (TFTs) by optimizing the source/drain materials. We successfully fabricate TZO TFTs with different source/drain materials, such as Al, Mo, Cr, Mo/Al/Mo and Cr/Al/Cr. No intentional substrate-heating is performed during each deposition step and the highest process temperature is 80°C. The results...
Thin film transistors (TFTs) with Gadolinium-doped Aluminum-Zinc-Oxide (Gd-AZO) thin film as the active layer were fabricated on glass substrate at room temperature. Amorphous Gd-AZO crystal structure which is benefit for high performance devices was obtained. The variation trend of TFTs properties with O2 partial pressure was investigated. Excellent negative bias stress stability and transmittance...
High quality Mn-Co-Ni-O (MCN) spinel films are prepared on Al2O3 substrate by RF magnetron sputtering (RF) and chemical solution deposition (CSD). The microstructural characterizations reveal the films present excellent crystallization and compact surface. The variable temperature electrical results show the films have temperature coefficient of resistance (TCR) of −3.8 %/K at 295 K. Based on the...
The wireless network technology is fast growing in recent years, make the mobile network equipment very general. So the transmission quality is more and more important. But the environmental change of the network is fast, the route may blocked and the route discover will be resumed. The common routing Protocol is AODV (Ad hoc On-Demand Distance Vector Routing) in IEEE802.11. Because route discover...
Delay Tolerant Network (DTN) is an approach applied to computer network architecture to address the technical issues in heterogeneous networks that may lack continuous network connectivity. Examples of these networks are those operating in the mobile or extreme terrestrial environments, or planned networks in space. In this paper, we optimize the implementation of DTN gateway and tested with the Video-On-Demand...
Based on the digital sampling technology, a new broadband phase difference calibration device is developed. The DFT and interpolation compensation algorithms under non-integer period sampling are used. The construction, sampling strategy and compensation algorithm of the calibration device are introduced in detail. Its uncertainty is evaluated and verified by experiments. The frequency of the device...
Voltage fluctuation and flicker is an important aspect of power quality. The key of flicker analysis is to track the envelope of voltage signals and then calculate the short-term flicker severity. In this paper, a new method on calibration of flickermeters was presented. The method did not adopt the phase-locked loop between the flicker waveform generator and the DVM. It tracked the envelope by interpolated...
For high-frequency resistive voltage divider, the distributed parameter model was studied and the key factors affecting its performance were discussed. The high-frequency characteristics of typical outer structure of voltage divider were simulated by ANSYS software. According to the reflection coefficient, VSWR and return loss, an optimized structure of divider for high frequency is presented.
There are two methods commonly used for the performance test of voltage divider system. Step response method is used to measure the transient response of system, and frequency response method is used to measure the amplitude-frequency characteristics and phase-frequency characteristics. This paper discusses the equivalent conversion relationship of the characteristic parameters of time-domain and...
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