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This work presents the architecture, modelling, simulation, and physical implementation of a versatile, scalable system for use in common-type waste-bins that can perform and transmit accurate fill-level estimates while consuming minimal power and consisting of low-cost embedded components. The sensing units are based on ultrasonic sensors that provide ranging information which is translated to fill-level...
RSVP Keyboard™ is a non-invasive electroencephalography (EEG) based brain computer interface (BCI) for letter by letter typing. In this system a sequence of symbols is presented on a computer screen in rapid serial visual presentation scheme to query a user's intent. EEG evidence and language model are used in conjunction for joint inference of the intended symbol. Usually repetition of sequences...
Approximate query processing with relatively small random samples is an effective way to deal with many queries on large databases. However, small random samples might miss relevant records for highly selective queries due to insufficient coverage. A multidimensional index tree called the k-MDI was proposed as an effective sampling scheme for highly selective decision support queries. It has been...
Medical literature have recognized physical activity as a key factor for a healthy life due to its remarkable benefits. However, there is a great variety of physical activities and not all of them have the same effects on health nor require the same effort. As a result, and due to the ubiquity of commodity devices able to track users' motion, there is an increasing interest on performing activity...
Feature selection and learning through selected features are the two steps that are generally taken in classification applications. Commonly, each of these tasks are dealt with separately. In this paper, we introduce a method that optimally combines feature selection and learning through feature-based models. Our proposed method implicitly removes redundant and irrelevant features as it searches through...
The roadmap towards the so-called Smart Grids calls for a clever and efficient management of the distribution systems. In this context, Distribution System State Estimation (DSSE) tools play a crucial role to acquire the knowledge about the effective operating conditions of the network and to enable the proper management and control functions operation. DSSE is usually performed by relying on a Weighted...
In this paper we present a novel algorithm for fast and robust stereo visual odometry based on feature selection and tracking (SOFT). The reduction of drift is based on careful selection of a subset of stable features and their tracking through the frames. Rotation and translation between two consecutive poses are estimated separately. The five point method is used for rotation estimation, whereas...
This paper studies how the accuracy of the step detection algorithm of a pedestrian dead-reckoning (PDR) system is affected by the sampling frequency and the filtering of the data gathered from a wrist-worn inertial measurement unit (IMU). On the one hand, results show that sensors sampling rate can be reduced and a similar accuracy can still be obtained, what it is very interesting for energy saving...
A novel approach based on the Method of Moments has been recently presented to analyse very large irregular arrays printed on layered substrates. However, that method requires some tuning to minimize the error in the layered medium Green's functions while presenting a low computation time. In this work, an analysis of the influence of every parameter on these two figures of merit is presented for...
In order to improve the accuracy of channel estimation in OFDM system, an improved algorithm Regularized Orthogonal Matching Pursuit (ROMP) Algorithm is proposed. The algorithm avoids choosing the wrong group and makes the group of atoms' energy more concentrated which is selected by modified regularized principle, then adds the secondary screening of estimation results, achieves an accurate reconstruction...
In order to improve the accuracy and speed of channel estimation in OFDM system, an improved Compressive Sampling Matching Pursuit (CoSaMP) algorithm was proposed. The new algorithm which improves the estimation accuracy and the estimation speed, added a least square estimation process to the estimation results. Moreover it optimized the number of atoms in candidate set and the terminal conditions...
This paper introduces a novel sequential approach to user movement analysis and tracking for indoor positioning systems. The algorithm utilizes stored reference and measured received signal strength indication (RSSI) data to determine the most likely movement paths represented as sequences of rectangular zones. It is demonstrated that the application of the proposed approach results in an improvement...
This paper presents an experimental analysis of the effect of physical orientation of a compact UWB antenna on the accuracy of range estimates between two such antennas using signal time-of-flight. A pair of identical miniature UWB antennas have been used for the investigations, in which one of the antennas is rotated in various directions in the vertical plane and the effect of this rotation on the...
Spectral estimation is one of the essential steps for the direction of arrival radars. Reduction of spectral estimation errors directly yields better accuracy in the calculated angles. In order to get high resolution in the spectral domain, a large data length or a high sampling frequency are required for the Fast Fourier Transform based spectral estimation techniques. This issue causes important...
Experienced pipeline operators utilize Magnetic Flux Leakage (MFL) sensors to probe oil and gas pipelines for the purpose of localizing and sizing different defect types. A large number of sensors is usually used to cover the targeted pipelines. The sensors are equally distributed around the circumference of the pipeline, and every three millimeters the sensors measure MFL signals. Thus, the collected...
Confirmation bias is the human tendency to search for, collect, interpret, analyse, or recall information in a way that confirms one's prior beliefs or preferences. In this paper, we review previous research and demonstrate confirmation bias and its effect in two software engineering contexts. The first study documents that managers bias their interpretation of randomly generated project data towards...
Recently, 60 GHz technology has become a promising alternative for indoor positioning systems because it can provide very accurate temporal and spatial information for precise time of arrival (TOA) estimation. However, non-line-of-sight (NLOS) propagation in indoor environments can significantly degrade the localization accuracy with 60 GHz signals. To reduce the effects of NLOS propagation, a fingerprinting...
This paper presents a ranging approach using an improved preamble sequence of orthogonal frequency-division multiplexing (OFDM) signal for 60 GHz system. The performance of range estimation with OFDM modulation under 60GHz channel is analyzed emphatically. In order to utilize the time-frequency characteristics of OFDM signal in the ranging system, the subcarriers phase difference algorithm with an...
In this paper we describe a technique for joint estimation of head pose and multiple soft biometrics from faces (Age, Gender and Ethnicity). Our proposed Multi-Objective Random Forests (MORF) framework is a unified model for the joint estimation of multiple characteristics that automatically adapts the measure of information gain used for evaluating the quality of weak learners. Since facial characteristics...
A 60 GHz ranging model is established and a strongest path search ranging algorithm based on beamforming is proposed. The range error caused by a non-line of sight (NLOS) channel is mitigated by modeling the corresponding delay bias. Outlier detection is employed to improve the accuracy. Performance results are presented which show that 60 GHz ranging can achieve centimeter level accuracy in indoor...
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