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With the fast development of the Internet, the lightweight 3-dimension (3D) geographic scenes visualization system is expected to play more important roles in web-based GIS. Finding an effective solution to render 3D geospatial data has great significance in Cartography and Geographic Information Systems. The emergence of HTML5, as well as WebGL (Web Graphics Library), provides a new approach for...
Supercavitating vehicles (SV) are a class of high-speed autonomous underwater vessels. They present a great challenge in designing the guidance law in comparison with the traditional autonomous underwater vehicles. This is due to the fact that their constraints and working environment are much more complex. To tackle the above challenge, an optimal nonlinear midcourse guidance logic is proposed by...
In this paper, we use SLR normal point observations provided by EDC to validate AIUB zero-difference kinematic orbit of GRACE satellites. By selecting 4 representative SLR sites, they are analyzed in detail from the regularity of observed elevation angle, azimuth angle and residual value of GRACE-A/B satellites. The results show that the data quality of different SLR sites is uneven, and more than...
This paper analyzes the transient performance of wind turbines with direct-driven permanent magnet synchronous generators (PMSGs) and compares PMSG models for power system transient stability studies. The control strategy of a PMSG is introduced firstly. Afterwards, the transient performance of a PMSG is analyzed in detail based on the PMSG's operating mechanism. To represent PMSGs in transient stability...
In the area of image encryption, a large number of algorithms have been developed to encrypt digital images using chaotic systems. The security of these encryption algorithms is usually limited due to the relatively small key spaces of the underlying chaotic systems used for encryption, especially in cases where the used chaotic systems are one-dimensional. In this paper, we develop a novel image...
Near Space Hypersonic Vehicle (NSHV) could play significant roles in both military and civilian applications. It may cause huge losses of both personnel and property when a fatal fault occurs. It is therefore paramount to conduct fault-tolerant research for NSHV and avoid some catastrophic events. Toward this end, this paper presents a novel fault-tolerant control strategy by using the LSSVM (Least...
Modeling, a common method in Earth science research, needs a significant amount of data for model initialization, validation, verification, and calibration. Most of those data requirements could be met by the Earth observation data and their derived products. However, currently the use of Earth observation data in modeling requires significant effort for data preparation. This paper presents a Web...
With the rapid development of Internet, text categorization becomes a mission-critical technology that organizes and processes large amounts of data in document. Deep belief networks have powerful abilities of learning and can extract highly distinguishable features from the high-dimensional original feature space. So a new Chinese text categorization algorithm based on deep learning structure and...
This paper studies the imbalanced data classifycation problem and proposes bi-directional sampling based on clustering (BDSK) for the imbalanced data classification. This algorithm combines SMOTE over-sampling algorithm and under-sampling algorithm based on K-Means to solve the within-class imbalance problem and the between-class imbalance problem. It not only avoid induce too much noise but also...
With the development of Internet, people have entered the era of New Media, and the demand for intelligent information is more intense. How to make news industry, provide more personalized and efficient service for all walks of life, is something worth exploring. In this paper, we aim to analyze the performance of segmentation, which is the foundation of text classification. Our study describes the...
This paper investigates the contribution of energy storage systems to the system frequency response in a large meshed transmission system. The case studies compare the contribution of two types of energy storage technologies, i.e., battery energy storage system (BESS) and flywheel energy storage system (FES), to improve frequency response in the test network. Case studies examine the effect of different...
DARPA initiated the Cyber Grand Challenge (CGC) in 2014 to encourage innovation in fully automated software vulnerability analysis and repair. In the June 2015 CGC Qualifying Event, the competitors' automated systems were given one day to evaluate 131 challenges. The top seven teams, including the University of Idaho's Center for Secure and Dependable Systems, will compete in the August 2016 CGC Final...
Feature dimension reduction is an important part in text categorization, and it even becomes more important for child classification in hierarchical text classification. It is presented that Chinese text feature selection method based on category distinction and feature location information in this paper. Experimental results show that the proposed method has a higher precision and recall rate than...
In June 2014, DARPA launched the Cyber Grand Challenge (CGC) to spur innovation in fully automated software vulnerability analysis and repair. The competitors' automated systems evaluated challenges in the CGC Qualifying Event, with the top seven including the University of Idaho's Center for Secure and Dependable Systems team moving on to the fully automated capture-the-flag competition, which will...
Many situations require two vector field measuring systems to work together, such as strap down navigation technology. Therefore, identify the spatial relationship between vector field measuring systems is a prerequisite for engineering applications. This paper deduces the relationship of two vector field measuring systems and proposes fitness function. Then use the self-evolutionary genetic algorithm...
This paper introduces self-learning mechanism into the basic particle swarm algorithm to present the improved particle swarm algorithm. The self-learning mechanism ensures that the particles can change their speed and positions base on self learning and the overall experience. The novel algorithm can dynamically increase the diversity of particle swarm offspring and reduce the human intervention in...
For the significance of the Near Space Hypersonic Vehicle(NSHV) at aspect of military and civilian and the huge losses of personnel and property when a fault occurs, it is significant to conduct fault-tolerant research for NSHV and avoid some catastrophic events. This paper presents a fault-tolerant control scheme of inverse system based on improved Least Squares Vector Machine(LS-SVM). The control...
In recent years, text categorization based on machine learning is a widely used technology in the field of natural language processing and text mining and has gained many advances. Feature selection is one of the key problems in text categorization. The chief obstacles to feature selection are noise and sparseness. In this paper, we propose an approach of Chinese text feature selection based on CV...
In order to realize the content-based image retrieval (CBIR), some characteristics of the images should be extracted like color, texture and shape. The extremely important thing in CBIR is to search the most similar database images to match the query image, which needs to improve the precision. This paper proposes an Improving Precision Priority (IPP) algorithm integrating vital features and the query...
Security tagging schemes are known as promising mechanisms for providing security features in computer systems. Tags carry information about the tagged data throughout the system to be used in access control and other security mechanisms. This paper discusses several different uses of security tags related to different security policies, highlighting appropriate uses of the tags. The evaluation of...
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