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To effectively address the explosive growth of multi-media applications over the Internet, a large-scale media streaming system has to fully take into account the issues of security, quality of service (QoS), scalability, and heterogeneity. However, current streaming solutions do not address all these challenges simultaneously. To address this limitation, this paper proposes a secure and high-performance streaming system called TrustStream, which combines the best features of scalable coding, content distribution network (CDN) and peer-to-peer (P2P) networks to achieve unprecedented security, scalability, heterogeneity, and certain QoS simultaneously under a unified architecture. In this architecture, raw video is encoded into two layers, namely, the base layer, which contains the most critical media content and is transmitted through a CDN-featured single-source multi-receiver (S-M) P2P network to guarantee a minimal level of quality, and the enhancement layer, which is transmitted in a pure multi-source multi-receiver (M-M) P2P framework to achieve maximum scalability and bandwidth utilization. Heterogeneity is therefore addressed by delivering only the layers that a receiver is able to manage. Security is provided by combining our key distribution mechanism and key-embedding scheme under' our proposed S-M P2P topology. We have implemented TrustStream system over the Internet. Deployed by ChinaCache, the largest CDN provider in China, TrustStream has broadcasted several popular live video programs over the Internet. The experimental results demonstrate the advantages and effectiveness of our architecture and system. [ABSTRACT FROM AUTHOR]

Accurate forecast of citywide passenger demand helps online car-hailing service providers to better schedule driver supplies. Previous research either uses only passenger order history and fails to capture the deep dependency of passenger demand, or is restricted on grid region partition that loses physical context. Recent advance in mobile traffic analysis has fostered understanding of city functions. In this article, we propose FlowFlexDP, a demand prediction model that integrates regional crowd flow and applies to flexible region partition. Analysis on a cellular dataset covering 1.5 million users in a major city in China reveals strong correlation between passenger demand and crowd flow. FlowFlexDP extracts both order history and crowd flow from cellular data, and adopts Graph Convolutional Neural Network to adapt prediction for regions of arbitrary shapes and sizes in a city. Evaluation on a large scale data set of 6 online car-hailing applications from cellular data shows that FlowFlexDP accurately predicts passenger demand and outperforms the state-of-the-art demand prediction methods. [ABSTRACT FROM AUTHOR]

Abstract: The distributed timing and synchronization system (DTSS) plays an important role in Experimental Advanced Superconducting Tokamak (EAST), which is one of the national key fusion research facilities in China. This system synchronizes each subsystem of EAST by using reference clock and trigger. A prototype DTSS module has been developed based on PXI bus and RIO (reconfigurable I/O) devices. The DTSS can provide reference clock in frequency up to 80MHz. The trigger can be pre-defined from 1ms to 6872s with 10ns accuracy. In addition, this system can acquire, process signals, and send output or command to other systems. The DTSS has been successfully applied to 2010 fall EAST experiment, and the results confirmed its accuracy and reliability. After the analysis of system requirement, the architecture of the DTSS and the technical implementation based on PXI are presented in this paper. [Copyright &y& Elsevier]

Abstract: Drawing on studies in media discourse analysis and advances in natural language processing, data mining and information access, a framework for automated sentiment analysis of news report from Western mainstream media is proposed and a preliminary experiment is reported in this paper. The automated sentiment analysis system architecture comprises (1) the identification of Chinese-English equivalent query expressions; (2) the construction of domain and linguistic knowledge bases; (3) the recovery of news events; and (4) the sentiment analysis over news texts. The workflow consists of two phases, i.e. an offline construction of resources, such as comparable or parallel corpora and domain knowledge bases, which are utilized in real-time processing, and an online analysis of news texts by means of machine learning and data mining techniques. The proposed methodology leads to a quick response to different information gathered from overseas media and an efficient decision-making procedure for e-government. [Copyright &y& Elsevier]

The Godson project is the first attempt to design high performance general-purpose microprocessors in China. This paper introduces the microarchitecture of the Godson-2 processor which is a 64-bit, 4-issue, out-of-order execution RISC processor that implements the 64-bit MIPS-like instruction set. The adoption of the aggressive out-of-order execution techniques (such as register mapping, branch prediction, and dynamic scheduling) and cache techniques (such as non-blocking cache, load speculation, dynamic memory disambiguation) helps the Godson-2 processor to achieve high performance even at not so high frequency. The Godson-2 processor has been physically implemented on a 6-metal 0.18µm CMOS technology based on the automatic placing and routing flow with the help of some crafted library cells and macros. The area of the chip is 6,700 micrometers by 6,200 micrometers and the clock cycle at typical corner is 2.3ns. [ABSTRACT FROM AUTHOR]

The Internet has become a major part of the global communications infrastructure supporting modern-day socio-economic development, social progress and technological innovation. Invented 30 years ago, today the Internet is facing severe challenges. Many countries have funded research projects on the new-generation Internet, such as GENI, FIND, FIRE and CNGI, in an effort to solve these challenges. In addition, over the past few years, the networking research community has engaged in an ongoing conversation about how to move the Internet forward, and there are now two different approaches towards Internet research. The first approach is based on using the existing Internet architecture to solve the major technical challenges--this is called 'evolutionary' research. The other, which is called the 'clean slate', involves the design of an entirely new Internet architecture. In the first part of this paper, the basic features of the next generation Internet and its principal contradictions are analysed. Then a survey of recent progress in the study of the next generation Internet in China is discussed. Finally, the focus and direction for the next step in research are presented as based on fundamental research into the international next generation Internet architecture, and the many new innovative demands placed on Internet architecture in recent years. [ABSTRACT FROM AUTHOR]