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Nowadays capturing the image of eyeball with camera and estimating gaze points using pupil positions is the most common method for eye-tracking devices. Head-mounted eye-tracking equipment has a wide range of application because of its flexibility and high gaze estimation accuracy. But the user's head should keep still using a chin rest or other tools, or will lead to enormous gaze estimation errors...
In this paper the elimination of image distortion and subsequent estimation of intrinsic camera parameters, while extracting the real object dimensions from photographs is presented. Research analysis includes description of the basic concepts related to the camera calibration. Following the analysis, the most suitable calibration method has been chosen and implemented as a software solution. The...
As for a compact Uniform Circular Array (UCA), the performance of Beam forming (BF) or Direction-of-Arrival (DOA) estimation will be severely degraded by strong electromagnetic mutual coupling effect, and the calibration method based on Rank Reduction (RARE) lacks robustness. Based on the special circular symmetry of a UCA, a new efficient and robust method is proposed to calibrate the mutual coupling...
The paper considers the problem of how to simultaneously estimate the direction-of-arrival (DOA) of a source signal and the phase error of a uniform linear array (ULA). We introduce a new method to estimate those parameters for a partly calibrated ULA. As its name suggests, partly calibrated ULA means a array with some of its sensor elements have been calibrated. In particular, our method can be well...
A new indoor calibration method is proposed to estimate and compensate mutual coupling and channel gain/phase inconsistency parameters for a uniform linear array (ULA). This calibration method employs only one assistant source in near-field and is unnecessary to conduct complex feed circuits behind the antennas. Firstly, accurate channel gain/phase deviation is estimated via an inside testing structure...
This paper presents a time-interleaved (TI) successive-approximation-register (SAR) ADC with a fast variance-based timing-skew calibration technique. It uses a single comparator-based window detector to calibrate the timing skew. It has low-hardware cost and 104 times faster convergence speed compared to prior variance-based timing skew calibration technique. The proposed technique brings collateral...
This paper introduces and demonstrates a combination scheme for the combination of Wi-Fi based and camera based localization technologies to increase the applicability in indoor environments. The scheme is developed on the basis of an analytical approach by looking for maximizing the probability of appearance and the reliability of the location results provided by underlying technologies. The proposed...
The time-dependent origin-destination (TDOD) demand estimation problem aims at estimating dynamic demand that represents the observed traffic flow patterns in a transportation network. Errors in TDOD demand are often propagated into the network outputs causing unreliable planning and operational policies. In this study, a bi-level optimization problem is proposed where the upper level is an Ordinary...
The diffusion of the Internet of Things paradigm, in the last few years, has led to the need of deploying and managing large-scale Wireless Sensor Networks (WSNs), composed by a multitude of geographically distributed sensors, like the ones needed for Smart City applications. The traditional way to manage WSNs is not suitable for this type of applications, because manually managing and monitoring...
Many vision-based systems have been proposed for intersection monitoring, but few of them use wide angle cameras. In this paper, we present a fisheye-stereo monitoring system that will be installed especially in rural areas. Our goal is to estimate the extrinsic calibration decoupled into a rotation followed by a translation. In the context of rural intersections, methods that purely rely on the geometry...
This paper proposes an online extrinsic camera calibration system able to determine the pitch and roll angle of a moving, forward-looking camera relative to the road surface. Some road surfaces do not show enough texture to allow reliable optical flow calculation and accurate per-frame pitch and roll estimations, respectively. If inaccurate per-frame estimations are regarded in the final calibration,...
High-maturity software development processes can generate significant amounts of data that can be periodically analyzed to identify performance problems, determine their root causes and devise improvement actions. However, conducting that analysis manually is challenging because of the potentially large amount of data to analyze and the effort and expertise required. In this paper, we present ProcessPAIR,...
Personal dead reckoning (PDR) localization technology can provide effective and critical assistance for public security, such as emergency rescue or anti-terror training in the indoor or underground environment without the need of deploying additional positioning infrastructure. However, the PDR suffers from the severe position error accumulation with time due to the inaccurate step length and moving...
The aim of this study was to develop an algorithm suitable for the estimation of 4-pyridoxic acid (4PA) concentration removed during dialysis through fluorescence measurements in spent dialysate. 4PA is the major urinary catabolite of vitamin B-6 (B6), that is regularly injected to dialysis patients. 4PA could be used to estimate B6 nutritional status of the patients. For the study 10 hemodialysis...
In foot-mounted positioning systems, it is hard to align multi-agent trajectories. In addition, the positioning accuracy is hard to maintain due to inertial drifts. An approach for trajectory initialization and calibration using iBeacons is proposed in this paper. This approach is under the framework of a particle filter. In the observation model of the particle filter, a nonparametric Gaussian Process...
This paper focuses on WiFi indoor positioning based on received signal strength, a common local positioning approach with a number of prominent advantages such as low cost and ease of deployment. Weighted k nearest neighbor (WKNN) approach and Naive Bayes Classifier (NBC) method are two classic position estimation strategies for location determination using WiFi fingerprinting. Both of them need to...
There are many important regression problems in real-world brain-computer interface (BCI) applications, e.g., driver drowsiness estimation from EEG signals. This paper considers offline analysis: given a pool of unlabeled EEG epochs recorded during driving, how do we optimally select a small number of them to label so that an accurate regression model can be built from them to label the rest? Active...
With regards to the fourth stage rocket, upper stage flight time can be up to 48 hours. Volatile space environment leads parameters calibrated in ground do not meet the requirements of the spacecraft precise orbit. In this paper, a real-time on-orbit calibration method of redundant laser gyro inertial measurement unit for space transfer vehicle is proposed. We make use of the high precise attitude...
This paper seeks an analysis of high-precisions standards of the microwave used by calibration of meters parameters transfer in coaxial paths, and methods for their calibration.
Localization, a process of determining the position of a blind node, can be used in various applications. Signal-strength localization provides a low-cost and lowpower solution to positioning. Signal-strength positioning approaches using fingerprinting or calibrated approaches require a time-consuming calibration phase. Existing selfcalibrating approaches, which do not require a priori calibration,...
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