For Wireless Sensor Networks （WSN） is responsible for sensing, collecting, processing and monitoring of environmental data, but it might be limited in resources. This paper describes in detail the compressed sensing...For Wireless Sensor Networks （WSN） is responsible for sensing, collecting, processing and monitoring of environmental data, but it might be limited in resources. This paper describes in detail the compressed sensing theory, study the wireless sensor network data conventional compression and network coding method. The linear network coding scheme based on sparse random projection theory of compressed sensing. Simulation results show that this system satisfies the requirements of the reconstruction error of packets needed to reduce the number of nodes to the total number of 30%, improves the efficiency of data communications in wireless sensor network, reduce the energy consumption of the system. With other wireless sensor network data compression algorithm, the proposed algorithm has the advantages of simple realization, the compression effect is good, especially suitable for resource limited, and the accuracy requirements are not particularly stringent in wireless sensor networks.展开更多
A codec is a device or computer program for encoding or decoding a digital data stream or signal. Codec is a portmanteau of coder-decoder. According to different technical principles of audio compression, audio compre...A codec is a device or computer program for encoding or decoding a digital data stream or signal. Codec is a portmanteau of coder-decoder. According to different technical principles of audio compression, audio compression coding methods have their own characteristics. This paper considers that the coding quality is high and the digital rate is also high. In addition, according to the compressed data whether exists information loss, data compression coding can also be divided into two forms, which is lossless compression and lossy compression. Lossy compression method also called compression method for the amount of information. Lossy compression is always larger, widely used in audio compression. It is also familiar to us. However, for the more critical to the quality of people, especially the music enthusiast, lossy compression of audio files often cannot meet their quality on the requirements, and it is very necessary and lossless compression. Firstly, this paper has designed and executed tests to compare the performance ofcodecs by using my methodology. Then, it has analysed the results. Finally, there are conclusions on the relative merits of the codecs selected and some recommendations.展开更多
This paper proposes a new method for the compression of vector data map. Three key steps are encompassed in the proposed method, namely, the simplification of vector data map via the elimination of vertices, the compr...This paper proposes a new method for the compression of vector data map. Three key steps are encompassed in the proposed method, namely, the simplification of vector data map via the elimination of vertices, the compression of re- moved vertices based on a clustering model, and the decoding of the compressed vector data map. The proposed compres- sion method was implemented and applied to compress vector data map to investigate its performance in terms of the com- pression ratio and distortions of geometric shapes. The results show that the proposed method provides a feasible and effi- cient solution for the compression of vector data map and is able to achieve a promising ratio of compression and maintain the main shape characteristics of the spatial objects within the compressed vector data map.展开更多
文摘For Wireless Sensor Networks （WSN） is responsible for sensing, collecting, processing and monitoring of environmental data, but it might be limited in resources. This paper describes in detail the compressed sensing theory, study the wireless sensor network data conventional compression and network coding method. The linear network coding scheme based on sparse random projection theory of compressed sensing. Simulation results show that this system satisfies the requirements of the reconstruction error of packets needed to reduce the number of nodes to the total number of 30%, improves the efficiency of data communications in wireless sensor network, reduce the energy consumption of the system. With other wireless sensor network data compression algorithm, the proposed algorithm has the advantages of simple realization, the compression effect is good, especially suitable for resource limited, and the accuracy requirements are not particularly stringent in wireless sensor networks.
文摘A codec is a device or computer program for encoding or decoding a digital data stream or signal. Codec is a portmanteau of coder-decoder. According to different technical principles of audio compression, audio compression coding methods have their own characteristics. This paper considers that the coding quality is high and the digital rate is also high. In addition, according to the compressed data whether exists information loss, data compression coding can also be divided into two forms, which is lossless compression and lossy compression. Lossy compression method also called compression method for the amount of information. Lossy compression is always larger, widely used in audio compression. It is also familiar to us. However, for the more critical to the quality of people, especially the music enthusiast, lossy compression of audio files often cannot meet their quality on the requirements, and it is very necessary and lossless compression. Firstly, this paper has designed and executed tests to compare the performance ofcodecs by using my methodology. Then, it has analysed the results. Finally, there are conclusions on the relative merits of the codecs selected and some recommendations.
基金Supported by the National 863 Program of China （No. 2007AAI2Z241）, the Program for New Century Excellent Talents in University （No. NCET-07-0643）, the National Natural Science Foundation of China （No. 40571134, No. 40871185）, the National 973 Program of China （No. 108085）.
文摘This paper proposes a new method for the compression of vector data map. Three key steps are encompassed in the proposed method, namely, the simplification of vector data map via the elimination of vertices, the compression of re- moved vertices based on a clustering model, and the decoding of the compressed vector data map. The proposed compres- sion method was implemented and applied to compress vector data map to investigate its performance in terms of the com- pression ratio and distortions of geometric shapes. The results show that the proposed method provides a feasible and effi- cient solution for the compression of vector data map and is able to achieve a promising ratio of compression and maintain the main shape characteristics of the spatial objects within the compressed vector data map.
