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Changes in nitrogen budget and potential risk to the environment over 20 years(1990–2010) in the agroecosystems of the Haihe Basin, China

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Journal of Environmental Sciences 2015年第2期27卷 195-202页

作者： Mengmeng Zheng Hua Zheng Yingxia Wu Yi Xiao Yihua Du Weihua Xu Fei Lu Xiaoke Wang Zhiyun Ouyang State Key Laboratory of Urban and Regional Ecology Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Wuhan University of Technology Computer Network Information Center Chinese Academy of Sciences

The nitrogen balance can serve as an indicator of the risk to the environment of nitrogen loss from agricultural land. To investigate the temporal and spatial changes in agricultural nitrogen application and its potential threat to the environment of the Haihe Basin in China, we used a database of county-level agricultural statistics to calculate agricultural nitrogen input, output,surplus intensity, and use efficiency. Chemical fertilizer nitrogen input increased by 51.7% from1990 to 2000 and by 37.2% from 2000 to 2010, concomitant with increasing crop ***, the nitrogen surplus intensity increased by 53.5% from 1990 to 2000 and by16.5% from 2000 to 2010, presenting a continuously increased environmental risk. Nitrogen use efficiency decreased from 0.46 in 1990 to 0.42 in 2000 and remained constant at 0.42 in 2010,partly due to fertilizer composition and type improvement. This level indicates that more than half of nitrogen inputs are lost in agroecosystems. Our results suggest that although the improvement in fertilizer composition and types has partially offset the decrease in nitrogen use efficiency, the environmental risk has still increased gradually over the past 20 years, along with the increase in crop yields and nitrogen application. It is important to achieve a better nitrogen balance through more effective management to significantly reduce the environmental risk,decrease nitrogen surplus intensity, and increase nitrogen use efficiency without sacrificing crop yields.

关键词： Nitrogen budget Nitrogen surplus intensity Nitrogen use efficiency Environmental risk Agroecosystem Haihe Basin

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Temporally or spatially dispersed joint RFID estimation using snapshots of variable lengths 15

Temporally or spatially dispersed joint RFID estimation usin...

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16th ACM International Symposium on Mobile Ad Hoc networking and Computing, MobiHoc 2015

作者： Xiao, Qingjun Chen, Min Chen, Shigang Zhou, Yian Key Lab of Computer Network and Information Integration Southeast University Ministry of Education China Department of Computer and Information Science and Engineering University of Florida GainesvilleFL United States

ISBN: (纸本)9781450334891

Radio-frequency identification (RFID) technology has been widely used in applications such as inventory control, object tracking, supply chain management. An important research is to estimate the number of tags in a certain area covered by readers. This paper extends the research in both temporal and spatial dimensions to provide much richer information for monitoring the dynamics of distributed RFID systems. More specifically, we are interested in estimating the joint properties of any two snapshots taken at arbitrary locations and arbitrary times in a system. With many practical applications, there is however little prior work on this problem. We propose a joint RFID estimation protocol based on a simple yet versatile snapshot construction. Given the snapshots of any two tag sets, although their sizes may be very different, we design a way to combine their information and more importantly derive formulas to extract the joint properties of the two tag sets from the combined information, with an accuracy that can be arbitrarily set. Through formal analysis, we determine the optimal system parameters that minimize the execution time of taking snapshots, under the constraints of a given accuracy requirement. Our simulation results show that the proposed protocol can reduce the execution time by multifold when comparing with the best alternative approach in the literature. Copyright © 2015 ACM.

关键词： Inventory control

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A Survey on information-Centric networking: Rationales, Designs and Debates

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China Communications 2015年第7期12卷 1-12页

作者： JIANG Xiaoke BI Jun NAN Guoshun LI Zhaogeng Institute for Network Sciences and Cyberspace Tsinghua University Department of Computer Science and Technology Tsinghua University Tsinghua National Laboratory for Information Science and Technology State Key Laboratory of Networking and Switching Technology BUPT

The basic function of the Internet is to delivery data(what) to serve the needs of all applications. IP names the attachment points(where) to facilitate ubiquitous interconnectivity as the current way to deliver data. The fundamental mismatch between data delivery and naming attachment points leads to a lot of challenges, e.g., mapping from data name to IP address, handling dynamics of underlying topology, scaling up the data distribution, and securing communication, etc. informationcentric networking(ICN) is proposed to shift the focus of communication paradigm from where to what, by making the named data the first-class citizen in the network, The basic consensus of ICN is to name the data independent from its container(space dimension) and session(time dimension), which breaks the limitation of point-to-point IP semantic. It scales up data distribution by utilizing available resources, and facilitates communication to fit diverse connectivity and heterogeneous networks. However, there are only a few consensuses on the detailed design of ICN, and quite a few different ICN architectures are proposed. This paper reveals the rationales of ICN from the perspective of the Internet evolution, surveys different design choices, and discusses on two debatable topics in ICN, i.e.,self-certifying versus hierarchical names, and edge versus pervasive caching. We hope this survey helps clarify some mis-understandings on ICN and achieve more consensuses.

关键词： information-centric networking content-centric networking future internet architecture named-data networking publish-subscribe

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Energy efficiency of wireless body area networks coexistence

Energy efficiency of wireless body area networks coexistence

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International Symposium on Antennas, Propagation and EM Theory (ISAPE)

作者： Ruixia Liu Yinglong Wang Shandong Provincial Key Laboratory of Computer Network Shandong Computer Science Center (National Supercomputing Center in Jinan) Jinan China College of Information Science and Engineering Shandong University of Science and Technology Qingdao China

ISBN: (纸本)9781509047444

Due to the energy limitation of sensor nodes, energy efficiency is one of the main concerns in the design of wireless body area networks (WBANs). Power control plays an important role in reducing network interference and resource management in WBANs. The task of power control is to achieve a certain goal by making use of smaller and suitable power transmission, which depends on the application and network distribution, including interference reduction, throughput maximization, QoS guarantee, topology control, and so on. This paper, using stochastic geometry, develop new nearest neighbor distance power control to increase the energy efficiency of WBANs coexistence.

关键词： Energy efficiency Wireless communication Wireless sensor networks Power control Body area networks Interference Ad hoc networks

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The Implementation of Intelligent Biochemical Monitoring System based on Cloud Platform

The Implementation of Intelligent Biochemical Monitoring Sys...

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International Conference on Industrial Technology and Management Science(ITMS 2015)

作者： T.L.Gao Y.L.Wang M.L.Shu S.J.Duan X.G.Gao School of Information Science and Engineering Shandong Normal University Shandong Key Laboratory of Computer Network Shandong Computer Science Center (National Super Computing Center in Jinan) School of Science Shandong Jiaotong University

In order to grasp the developing rules of chronic illness better, give timely and accurate treatment, and reduce the risk of syndromes occuring, we need more time for patients with some of themselves long-term health indicators for monitoring, and adjust the diet structure and treatment. Aiming at the present development situation and social demand of current cloud computing and health awareness, this paper mainly designed a system of Intelligent biochemical monitor system based on cloud computing. The system uses wireless sensor technology, Bluetooth technology, network communication technology and cloud storage technology based on cloud computing. It is composed of the wireless biochemical data collection sensor, intelligent mobile terminal and the cloud platform. It can complete the measurement of biochemical data, wireless data transmission, data storage, historical data trend and intelligent risk early warning function conveniently and reliably.

关键词： Wireless intelligent terminal MSP430 Bluetooth Biochemistry Cloud computing

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Efficient subtree results computation for XML keyword queries

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Frontiers of computer Science 2015年第2期9卷 253-264页

作者： Ziyang CHEN School of Information Science and Engineering Yanshan University Hebei 066004 China Environmental Management College of China Hebei 066004 China The Key Laboratory for Computer Virtual Technology and System Integration of HeBei Province Yanshan University Hebei 066004 China

In this paper, we focus on efficient construction of restricted subtree （RSubtree） results for XML keyword queries on a multicore system. We firstly show that the perfor- mance bottlenecks for existing methods lie in 1） computing the set of relevant keyword nodes （RKNs） for each subtree root node, 2） constructing the corresponding RSubtree, and 3） parallel execution. We then propose a two-step generic top-down subtree construction algorithm, which computes SLCA/ELCA nodes in the first step, and parallelly gets RKNs and generates RSubtree results in the second step, where generic means that 1） our method can be used to compute dif- ferent kinds of subtree results, 2） our method is independent of the query semantics; top-down means that our method con- structs each RSubtree by visiting nodes of the subtree con- structed based on an RKN set level-by-level from left to right, such that to avoid visiting as many useless nodes as possible. The experimental results show that our method is much more efficient than existing ones according to various metrics.

关键词： XML SLCA/ELCA RSubtree RKNs parallel

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Efficiently mining top-k high utility path patterns in software dynamic call graph

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ICIC Express Letters 2016年第1期10卷 211-218页

作者： He, Haitao Yin, Tengteng Wu, Hongfei Ren, Jiadong College of Information Science and Engineering Yanshan University No. 438 West Hebei Ave Qinhuangdao China The Key Laboratory for Computer Virtual Technology and System Integration of Hebei Province Yanshan University No. 438 West Hebei Ave Qinhuangdao China

Software behavior mining is a very meaningful work. Finding that desirable patterns can assist the program maintainers to comprehend the software adequately. Although the existing high utility pattern mining algorithms can discover all the patterns satisfying a given minimum utility, it is often dicult for users to set a proper minimum utility. In this paper, an ecient algorithm TUPP is presented to mine top-k high utility path patterns in software dynamic call graph. In TUPP, software paths are extracted from software dynamic call graph and the utility of functions is dened rstly. Secondly, a novel structure called PUAList is put forward. The structure stores both the adjacency items and the utility information which is heuristic information for pruning the search space. In addition, two strategies for raising the threshold and one pruning strategy are incorporated into TUPP to increase the eciency. At last, our experiments are conducted on both synthetic and real datasets. The results show that TUPP incorporating the eciency-enhanced strategies demonstrates impressive performance. © 2016 ICIC International.

关键词： Graph theory

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A weighted clustering algorithm based on user’ access sequence similarity

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ICIC Express Letters 2016年第10期10卷 2363-2370页

作者： Li, Weina Han, Gaowei Ren, Jiadong College of Information Science and Engineering Yanshan University No. 438 Hebei Ave. Qinhuangdao066004 China The Key Laboratory for Computer Virtual Technology and System Integration of Hebei Province No. 438 Hebei Ave. Qinhuangdao066004 China

Consider traditional clustering algorithms seldom had a research on users’ visit behavior and content, and they cannot cluster users with similar visit behavior into a community easily. Behavior of user cannot cluster users with similar visit behavior i also reflect usery. Behavior Therefore, setting about the log of user’s access behavior, in view of visitor volume, sequences of accessing keywords and time interval between keywords, a weighted clustering algorithm based on sequence similarity which is called K-Similar is put forward. Starting from behavior of user’s access to document, users are clustered, and important users are divided into a community. Then, literature needs of users in the same cluster are mined. This algorithm has been verified in users users are log data in CNKI, available for academic publishing. Experimental results show that K-Similar is more efficient in efficiency and accuracy. It can obtain more interesting user communities and show academic publishing demand of special users. © 2016 ICIC International.

关键词： Clustering algorithms

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An energy saving strategy in digital cognitive radio networks and its performance assessment

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ICIC Express Letters 2016年第6期10卷 1367-1373页

作者： Jin, Shunfu Chen, Si School of Information Science and Engineering Yanshan University No. 438 Hebei Ave Qinhuangdao066004 China Key Laboratory for Computer Virtual Technology and System Integration of Hebei Province Yanshan University No. 438 Hebei Ave Qinhuangdao066004 China

With the explosive growth of wireless application, how to improve the spectrum efficiency as well as reduce the communication consumption is a hot topic of research. In this paper, we propose a novel energy saving strategy in digital cognitive radio networks (CRNs). The key idea of this strategy is to set the base station (BS) of CRNs into sleep state when there are not any packets to be transmitted. Accordingly, we develop a Markov chain model to assess the average latency of secondary user (SU) packets and the energy saving ratio of system. Finally, we provide numerical results to show that there is a tradeoff when setting the sleep timer length for the proposed energy saving strategy. © 2016 ISSN.

关键词： Energy conservation

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In-rank: An entropy-based informative nodes mining method in complex software network

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ICIC Express Letters 2016年第7期10卷 1683-1689页

作者： Ren, Jiadong Li, Yanling Wu, Hongfei Liu, Yang Zhang, Peng College of Information Science and Engineering Yanshan University No. 438 Hebei Avenue Qinhuangdao066004 China The Key Laboratory for Computer Virtual Technology and System Integration of Hebei Province Yanshan University No. 438 Hebei Avenue Qinhuangdao066004 China

It is a fundamental issue to find a small subset of influential individuals in a complex network such that they can spread information to the largest scope of nodes in the network. Informative functions in complex software network can lead maximum information propagation scope, and mining such function nodes is important to understand the system’s topology structure and information transfer flows. In this paper, a novel topk informative nodes mining approach based on global information in directed-weighted complex software network is proposed. Firstly, we map functions and call relationships between them as a Directed-Weighted Function Call network (DWFCN). Secondly, an algorithm path-compute based on Software Executing Path Sequence (SEPS) generated by Depth-First-Search strategy is used to compute the software executing paths and get nodes’ information Accessible Set (AS). Thirdly, algorithm Entropy-Compute is proposed to calculate each source node’s information entropy in each information transfer flow process. Finally, an Informative Node Rank (IN-Rank) algorithm is put forward to mine most informative nodes. Experimental results show that our new method is accurate and effective. © 2016, ICIC Express Letters Office. All rights reserved.

关键词： Mining

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