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The Chelyabinsk meteorite fragment that landed in the Chebarkul lake in Russia on February 15, 2013 weighed over half a ton. We provide magnetic field maps that were obtained during underwater measurements above the fragment. The data acquisition process was multiple global position system referenced magnetic surveys 0.5–1 m above the top of the lake sediment layer at 10 m water depth. Gradiometric...
The Transfer Equipment Cask (TECA) is a key solution for Remote Handling (RH), and the bidirectional sealing door system (BSD) is the key component of the TECA. The control system of BSD is introduced in this paper. Moreover, the experiment on TECA indicates that the design of control system is feasible and the effect is satisfactory.
In this paper, we verify a bias reduction algorithm proposed earlier through experiments. The accuracy of localization systems are influenced by many factors. Our focus is to improve the performance of localization systems by reducing the estimation bias. Many algorithms have been proposed to reduce bias, however, only simulation results are presented which only demonstrate the algorithms with ideal...
Group audience responds collectively to a stimulus unlike an audience. Total group arousal is formed by exchanging emotional effects with surroundings. Empirical approaches are not enough by comparison to various theoretical approaches related to group arousal. Thus we have preceded the study for empirical group arousal measurement based on movement synchronization of group. At first, we measure that...
Wireless Body Area Networks (WBANs) can take advantage of many wireless protocols. Among them, Bluetooth is a good candidate since its widespread adoption guarantees compatibility with a number of devices and significantly reduces development time. In most cases data collected from different sensors on different nodes need to be synchronized. We present a synchronization protocol that makes use of...
In this paper we present a prototype location estimation system which uses Time Difference of Arrival. The system consists of five low cost sensors that are synchronized using GPS time stamps. The sensors were installed on the rooftops of the university campus. The system is based on software defined radios which enable receiving signals with different carrier frequencies and sampling rates with the...
Cyber-physical system (CPS) is a system featuring a tight combination and coordination between the system's computational and physical resources. As a CPS representative, the Weather Monitoring and Train Traffic Control Simulation System (WMT2CS2) includes two subsystems: the wireless sensor network front end and the train traffic control simulation subsystem. The sensing front end collects the real-time...
The electroencephalogram (EEG) signals reflect local potential changes that occur on pyramidal cells. Based on the received signals, epileptic seizure and sleep patterns can be monitored and diagnosed. This paper proposes a distributed sensing method using cooperative communication and networking between a pair of sensors for wireless sleep EEG signal collection. The proposed scheme is applied to...
Accuracy and power saving are two important quality of service (QoS) metrics in most applications of wireless sensor networks (WSNs) especially in acoustic target localization. The middleware layer of WSNs is responsible to properly manage the network-level resources and accurately setting the network parameters in support of these two application-level QoS metrics. A critical middleware-level task...
Continuous surveillance of a remote field is one of the applications of wireless sensor networks (WSNs). Acoustic target localization is one of the methods that are used in surveillance application. Accuracy of acoustic target localization is one of the most important quality of service (QoS) metrics that greatly depends on the accuracy of time synchronization. Power saving is another important requirement...
In cognitive radio networks, secondary users conduct local sensing to use underutilized spectrum bands. However, every secondary user's local sensing usually gives rise to much sensing overhead. Moreover, a globally synchronized quiet period cannot be determined in a decentralized network. In this paper, we propose a zone-based distributed sensing scheme, in which multiple secondary users alternate...
This paper presents an asynchronous virtual slot-based ranging (AVSR) utilizing broadcast ranging request. The utilized virtual slot is accomplished in a fully distributed manner among reference nodes. The evaluation result demonstrates that in spite of very low traffic intensity, AVSR is more robust against ranging error than conventional ranging schemes: TWR and SDS-TWR.
Adding location to the available information enables a new category of applications. With the constrained battery on cell phones, energy-efficient localization becomes an important challenge. In this paper we introduce a low-energy calibration- free localization scheme based on the available internal sensors in many of today's phones. We start by energy profiling the different sensors that can be...
Many existing Wireless Sensor Network (WSN) synchronisation protocols have demonstrated microsecond-level accuracy is achievable. Furthermore, sub-microsecond-level accuracy has recently been reported, although rather sophisticated, relatively bulky and custom-designed hardware were needed. This paper addresses a fundamental problem in WSN synchronisation: is there a more elegant way to achieve precise...
Accurate measurements of athletes' stride parameters, such as stride/step length, stride/step frequency, stance times and foot contact times are important to coaching support and biomechanics research in sprinting. Existing stride parameter monitoring approaches are either expensive, or insufficiently accurate, or not suitable for supporting daily training sessions. This paper investigates the use...
Stride-related parameters of sprinters, such as split times (i.e. which is speed-related), foot contact times, stance times, stride/step length, and stride/step frequency, etc. are important factors which affect athletes' performances. Traditionally, this information is captured by biomechanics researchers and coaches using optical-based systems. However, these systems are expensive, time consuming...
In this study, the hybrid Cramer-Rao bound (CRB) is developed for target localization, to establish the sensitivity of the estimation mean-square error (MSE) to the level of phase synchronization mismatch in coherent multiple-input multiple-output (MIMO) radar systems with widely distributed antennas. The lower bound on the MSE is derived for the joint estimation of the vector of unknown parameters,...
Mobile mapping system has become an irresistible trend used for 3D urban environment modeling, transportation engineering, road survey and other applications during last few years. A typical car-borne laser scanner based mobile mapping system today can be considered as a multi-sensor system that integrates various navigation devices and data acquisition sensors on a rigid, moving platform like a van...
"Business Microscope" visualizes interactions among knowledge workers in organization by sensing their face-to-face communication using sensornet. To analyze the workers communication in detail, speaker recognition for each node is needed. In the conventional studies, specific speaker-dependent training samples and acoustic model are required to recognize each speaker. In this work, speaker...
Target tracking is one of the popular applications of wireless sensor networks (WSN). Randomly distributed sensor nodes(motes) in environment gather spatio-temporal information about target(s) and send them to a sink node for further processing. Motes like personal computers use low cost crystal based clocks. In order to maintain synchronization accuracy to acceptable levels, we shall need to synchronize...
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