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With the advancements of electronic medical equipment, e-healthcare system becomes a promising paradigm to continuously monitor health conditions and remotely diagnose phenomena. Meanwhile, it generates a large volume of health data and poses several security challenges, such as access control and privacy leakage. In this paper, we propose a lightweight and privacy- preserving fog-assisted information sharing scheme (PFHD) for health big data. Specifically, we integrate fog computing into e-healthcare system to pre-process the raw health data and improve the efficiency of health data analysis. Furthermore, to prevent privacy leakage, we design a hierarchical attribute-based encryption method by encrypting the profile and health data with different access policies. In addition, we reduce the computation cost on devices by offloading health data encryption from devices to fog servers. Security discussions show that PFHD can achieve fine- grained health data sharing with privacy preservation. Performance evaluations demonstrate the efficiency of PFHD, especially in terms of encryption computation and storage costs.

Although cloud computing has made significant achievement, it still faces many challenges, such as slow interactive performance and unsatisfying user experience over a long-haul wide-area or wireless network. To address these challenges, we proposed a software-defined streaming-based code scheduling framework according to the concept of transparent computing. This framework uses the idea of code streaming to decouple the computation and storage of software codes, this idea also leverages the input/output virtualization technique to support legacy operating systems and application software in a feasible and effective way. The software-defined code scheduling framework allows the computation or storage to be adaptively carried out at appropriate machines with the assistance of performance and capacity monitoring facilities. Thus, the framework can improve application performance and user experiences by executing software codes on a nearer or better machine. We developed a pilot system to investigate the advantages of the proposed framework. Preliminary experimental results show that our approach can achieve a better performance than current cloud computing-based systems.

Because of benefit from the strategy of open source and the strong ability of innovation, Android has become one of the most popular operating systems on mobile platform. While the explosive increase of mobile applications has leaded to several shortages in Android system, such as the limitations in hardware resources, complex and frequent updating of the applications. In this paper, we propose a new kind of mobile application model named Streaming Application Model by absorbing the concept of Transparent Computing. The applications are modularized into some independent components and stored on server. The android devices load and launch the components dynamically. Streaming Application Model can reduce the consumption of hardware resources and take away the complex and frequent application update processes for users, thus improving the user experience in Android devices.

Polar codes are a class of codes proposed currently, which can achieve the capacity of binary symmetric channel with low encoding and decoding algorithm. By generalizing the definition of Bhattacharyya parameter in discrete memoryless channel, we discuss the performance of polar codes on wireless communication channels in this paper. We present the special expressions of the parameters for continuous channels (Gaussian and Rayleigh fading channels), including the recursive formulas and the initial values, and we discuss the construction of polar codes for Gaussian and Rayleigh fading channels. We analyze the application of polar codes with the defined parameter over Rayleigh fading channel by transmitting image signals. The simulation results show that polar codes have better performance than that of low density parity-check codes (LDPC) codes with the same simulation condition. It is shown that polar codes will be a good candidate for wireless communication channels.

Informanization, which serves as an important part of the agricultural industry, plays a crucial role in electronic commerce. The agricultural products sales have attracted more and more attention in the research and application field. This paper analyzes the limited factors of developing agricultural products electronic commerce in China, from the perspective of two representative e-commerce cases in Japan, which are “Irodori” in Tokushima prefecture and “Tosasenri” in Kochi prefecture, and put forward a systematic e-commerce mode linked by cooperation organization which includes the government, agricultural economic cooperation organization (AECO), and the third party logistics.