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Compared with the infrared focal plane array (IRFPA) based on amorphous silicon (α-Si), IRFPA based on vanadium oxide (VOx) has the advantages of big temperature coefficient, low noise and so on. Therefore, it is believed that VOx IRFPA has important application in both military and civil field. In this paper, the designs of driving module and signal processing module of VOx IRFPA are proposed. Firstly,...
Super-resolution (SR) algorithms for video sequences with high resolution (HR) guide frames can provide outstanding performances. Non-local means (NLM) algorithm compares the similarity between a pixel and its neighbors. NLM replaces every pixel with a weighted average of its neighbors. The NLM based SR algorithm can super-resolve low resolution (LR) frames using the HR guide frames in the video sequence...
Massive Multiple-Input Multiple-Output (MIMO) is an emerging research field due to the increasing demand of spectral efficiency in wireless broadband systems, such as Long Term Evolution (LTE) which is proposed by 3GPP (Third Generation Partnership Project). Precoding is important to exploit the performance of massive MIMO, and codebook design is crucial due to the limited feedback channel. In this...
An approach of 3D path planning for AUV on the basis of virtual terrain and thread map is proposed. The virtual terrain is constructed to predigest the 3D search space, transforming the 3D path planning to 2D path planning. Then, the thread map is made for unification of hostile threat and terrain. To obtain standout expansibility, an improved A∗ algorithm based on circle searching is applied for...
According to trajectory tracking problem in terrain survey mission, trajectory scheduling and control method is researched for unmanned underwater vehicle (UUV). Cross track error and line of sight combined guide is used for trajectory indirect control. In order to ensure precision, track and heading error are both used to switch guide method. Meanwhile, inserting medi-task scheduling strategy is...
The problem of path planning for UUV in time-varying ocean flows is considered. A method of path planning with biased extension is proposed to guarantee that the path is feasible and optimal. Considering the anisotropy of ocean flows and the motion constraint of UUV, a simplified space is obtained after the sub-nodes are expanded in special orientation. An integrated cost function is proposed to fulfill...
This paper presents a mission control approach and an on-board fault recovery to enable an autonomous underwater vehicle (AUV) to carry out the oceanographic survey autonomously. The challenges of AUV's operability in clutter environment have led the researchers to develop intelligent control architectures composed of distributed, independent and asynchronous behaviors, so the multi-agent system is...
Modern robust control theory was brought in the parameters design of tank stabilizers for ship, which can solve the nonlinear and model uncertainty exist in ship-tank-stabilizer system. An objective function for parameters optimization of tank stabilizers was established, which is suitable for tanks of different structure and system composed of multiple tanks. The simulation result shows that the...
Beamforming is an array processing technique that is applicable for either radiation or reception. In receiving beamforming an array collects spatial samples of impinging waveforms, and then a set of carefully calculated weights are applied to the multi-channel data to separate the desired signal from unwanted interference. In this paper we describe a sequential beamspace beamforming method using...
As is well known, quality of service (QoS) routing problem plays an important role in providing quality of service in traditional IP network To find a QoS constraints route, this paper makes a model for the problem based on specific multiple parameters and then analyzes simple genetic algorithm. Besides, fitness function is modified to gain better accuracy and classify-based idea is also bring into...
We have developed a sequential beamspace method for high resolution direction of arrival (DOA) estimation. Beamspace MUSIC and element space MUSIC DOA estimation algorithms have been implemented to utilize an 8 element uniform circular array operating at 5.8 GHz. The simulation and initial lab results show that the proposed method can achieve good accuracy once it is properly sychronized. In addition,...
This paper focuses on the annual cycle, difference frequency and spatial characteristic of 24 and 4 times manual observation for temperature and those of 24 and 8 times, too. It shows 4times manual observation mean temperature is lower than 24times value about 0.11 ° C. Whereas 8 times manual observation mean temperature is very close with 24 times value, and the difference frequency reaches 88.9%...
China station precipitation data from 1951 to 2008, NCEP/NCAR reanalysis, Hadley SST and CAM3 model of NCAR are used. This paper focuses on anomalies of precipitation in South China from autumn to winter and the characters of circulation and the influence of ENSO to precipitation and circulation. The particularities of drought in South China from November 2008 to January 2009 and its climate background...
This paper describes our design of a compact and efficient beamspace direction of arrival (DOA) estimation and beamspace beamforming device. The robust functionality includes high resolution RF emitter DOA estimation and beamforming in a noisy environment with strong interference. Simulations for beamspace DOA estimation using beamspace MUSIC and beamspace Capon methods are presented in conjunction...
This paper presents the development and implementation of a scheduling method that enables the BSA Autonomous Underwater Vehicle (AUV) to perform a mission operation while managing various resources autonomously. The mission is to survey several local areas in a dynamic ocean environment with different survey sensors. When a mission begins, it is assumed that during the execution of the mission, there...
This paper presents a probabilistic numerical approach for stability analysis of soil and rock slopes. The slope is divided into a family of inclined slices, and according to the upper bound theorem in plasticity theory, a work-energy balance equation is constructed for each soil/rock slice. Geotechnical parameters such as the cohesion, the friction angle and the pore pressure ratio etc. are modelled...
This paper describes an RF source localization and tracking system using an 8-element uniform circular array. The system is capable of precise RF source localization, fast target recognition and discrimination, fast spectral sensing, real-time processing for location tracking, and the suppression of jamming and multi-path signals. Existing systems and technology for precision location and tracking...
Based on the systematical analysis of factors influencing government knowledge management and researching the process of knowledge management, this paper establishes a comprehensive index system to evaluate the level of government knowledge management quantitatively, which complements to the existing evaluating methods. A case study was included to demonstrate how the established index system can...
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