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More and more attentions have been paid to the research of echolocation signals of tooth whales these years. However, due to the high-frequency characteristics of the signals, the sampling rate of many of the experimental data can be up to 500 kHz or even 2000 kHz, which lead to a huge amount of experimental data, this bring some difficulties to the follow-up storage and analysis work. However, due...
We investigate the problem of joint AP coverage adjustment and user association optimization for load balancing in multi-rate WLANs in this paper. We first divide the problem into two sub-problems and then formulate them as mixed integer linear programming models, which aim to minimize the AP utilization of the most congested AP while satisfying users' traffic demands. Then we design two corresponding...
The construction of wavelet synopses with maximum error bound have been studied by many years, which has many real world applications, such as health data stream analysis and image compression. Recently, there are two kinds of wavelet synopses with maximum error bound: one is restricted wavelet synopses whose synopses are restricted to the haar coefficients. Another is unrestricted wavelet synopses...
In this paper, nuclear radiation distribution (NRD) prediction is discussed and modelled. Firstly, the nuclear radiation distribution model in static state is studied, and the leakage source is regarded as a continuous leak point and proliferating around in evenly speed. The density of the NRD is calculated under the conditions of wind, ground reflection, particle sedimentation and nuclear decay....
In this paper, nuclear radiation distribution (NRD) prediction is discussed and modelled. Firstly, the nuclear radiation distribution model in static state is studied, and the leakage source is regarded as a continuous leak point and proliferating in evenly speed. The density of the NRD is calculated under the conditions of wind, ground reflection, particle sedimentation and nuclear decay. A detection...
In multi-radio wireless networks, it is vital to efficiently utilize the resource of non-overlapping channels, and thus the problem of channel assignment has been widely studied. Most proposed channel assignment approaches focus on reducing interference or maximizing throughput, assuming that all the radios on each node are keeping active. However, it is a significant waste of energy when network...
For linear systems, the optimal filtering is provided by the celebrated Kalman filter. For nonlinear systems, only suboptimal filters can be obtained in general. The Extended Kalman filter (EKF) is such a suboptimal filter. It helped the promotion of the Kalman filter. With the development of more advanced nonlinear filters, however, the EKF is receiving less and less attention because it performs...
Based on the detailed investigation and research of the balance mechanism of tail in primates, we designed a robot with a 3-DOF tail. By utilizing zero net angular momentum maneuvering, and implementing a dynamic feed-forward controller combining with a proportional-derivative controller for our tailed robot, it can self-right from the initial orientation, and avoid flipping over after a large perturbation.
This paper provides a closed form analytical solution for TDOA three dimensional (3D) acoustic source localization with four synchronized ultrasonic generators or receivers. Then a pure analytical solution for Geometric Dilution of Precision (GDOP) with four signal generators or receivers is derived instead of a least square solution. The proposed GDOP model removes the effect of time clock drift,...
In this paper, different types of batteries are summarized which are used in electric vehicles. The performance of the battery, including material, duration, environment impact such factors can seriously restrain the development of renewable vehicles. Battery state-of-charge (SOC) plays an important role in vehicle driving regulation. Hence, the methods of battery SOC estimation based on different...
The analysis of Electroencephalogram (EEG) signals plays a very important role in the biomedical domain and has many applications. It is extensively used in the Brain-Computer Interface (BCI) system and can be used for disease diagnosis, disease treatment, etc. The two main technologies of EEG signal analysis is feature extraction and pattern recognition. The key features of EEG signals can be obtained...
The electric vehicle (EV) industry has been in a fast development stage with great promotion from the government, which has also brought the construction of charging stations. The large-scale EVs charging behaviours can bring a huge effect on the power grid due to their popularity, types, charging time, charging patterns and different characteristics. Here, the state-of-art of the connection of EVs...
At present, vehicle to grid (V2G) technology has been received widely attention since a large amount of electric vehicles entering into the market gradually. The electric vehicle (EV) as a specific electricity load, can be used as a mobile storage device to participate load adjusting in the power grid and to provide platform for the renewable energy sources coordination. The management strategies...
A magnetron injection electron gun based on carbon nanotube cold cathode is developed in this paper, which is designed for a 0.22THz TE03 mode gyrotron. The experimental results of electron gun show that the maximum beam current reaches 30mA and an average radius of 1.2mm beam spot are achieved by using ITO glass. And the beam current density is increased 100 times.
In this paper, the design of a double-anode magnetron injection gun for a 0.56THz third harmonic gyrotron is presented. Simulation predicts that a high quality electron beam is generated with parallel velocity spread of 2.19%, perpendicular velocity spread of 1.0%, and velocity pitch spread of 3.18% at α=1.5. The variations of velocity spread due to operation parameters are also presented.
In order to develop the microwave and millimeter-wave vacuum electronic radiation source devices with field emission cold cathodes, an electron-optical system based on carbon nanotube cold cathode is investigated in this paper. A magnetron injection electron gun is designed for a 220GHz TE03 mode gyrotron. And the preliminary experiment results of the carbon nanotube cathode show the maximum beam...
This paper presents a nuclear radiation detection and monitoring system based on Wireless Sensor Network (WSN). There are three main highlights in our system. First, we adopt the popular WSN technology-Zigbee which provides many merits such as low energy consumption, ease of deployment, scalability, reliable data transmission and low cost. Second, in order to save the power, as most Zigbee devices...
Wireless sensor network (WSN) has been widely used in environmental monitoring. This paper presents a remote monitoring system for monitoring the safety of nuclear power plant. The system mainly consists of two parts: sensor network module and web monitoring module. The sensor network module transmits data via Zigbee sensor nodes which are powered by UPS power supply. We design a web interface for...
This paper proposes a distributed node election algorithm to efficiently select a subset of nodes which provide full coverage. In addition the boundary of un-triangulated holes can be accurately detected. This algorithm only uses binary connectivity information without any additional information such as sensing range or distance between nodes. Assumptions of a Unit Disk Graph (UDG) or d-quasi UDG...
An electron gun based on a carbon nanotube cold cathode is investigated. The experiment results show that when the inner and outer radius of cathode are 4.5mm and 6.5mm, a 4mA/10kV annular electron beam can be obtained. The area compression ratio of the electron beam is 10.
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