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CIRM: A candidate item reduce method on mapreduce for meteorological big data application

Energy Education Science and technology Part A: Energy Science and Research 2014年第6期32卷 6209-6220页

作者： Xue, Shengjun Huang, Junsheng Xu, Xiaolong Zhang, Jie Jing, Lu Nanjing University of Information Science and Technology School of Computer and Software Nanjing China Nanjing University of Information Science and Technology Jiangsu Engineering Center of Network Monitoring Nanjing China Nanjing University State Key Laboratory for Novel Software Technology Nanjing China Nanjing University Department of Computer Science and Technology Nanjing China Shanghai Meteorological Information and Technical Support Centre Shanghai China Computer Science Department Oklahoma State University StillwaterOK United States

With the increase of the number of meteorological stations, the meteorological data is growing rapidly. Association analysis algorithm is widely applied to the analysis of meteorological data. The traditional association analysis algorithm is difficult to meet the needs of meteorological big data processing. In order to solve this problem, in this paper, we propose a candidate item reduce method named CIRM. It aims at reducing the times of searching data sets and the number of generating candidate sets. To improve its scalability and efficiency in big data environment, CIRM is implemented on Hadoop, a widely-adopted distributed computing platform using the MapReduce parallel processing paradigm. Finally, extensive experiments are conducted on meteorological data sets, and results demonstrate that CIRM significantly improves the efficiency and scalability of the meteorological analysis data over existing approaches. © Sila Science. All rights reserved.

关键词： MapReduce

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Internal and external optical feedback effect in fiber linear lasers

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Journal of networks 2013年第9期8卷 1990-1996页

作者： Zhou, Junping Xia, Jingming Ge, Yixian Chernoff, Eric Jiangsu Key Laboratory of Meteorological Observation and Information Processing Jiangsu Technology and Engineering Center of Meteorological Sensor Network Nanjing University of Information Science and Technology Nanjing China Hangzhou International School Hangzhou China

In this paper, models of internal and external optical feedback effect in fiber linear lasers have been presented. The effects of optical feedback could be equivalent to the variation of laser cavity loss, and the output expressions of two models are deduced. According to the simulation results, the optical feedback system in fiber linear lasers has the same phase sensitivity as the traditional self-mixing effect in semiconductor lasers. The experimental results show a good agreement with the simulated results. Comparing the output of internal structure with that of external structure, we can conclude that the internal optical feedback system can get higher output gain and stripe depth, which reveals that the internal feedback structure has better sensing characteristics. © 2013 ACADEMY PUBLISHER.

关键词： Fiber lasers

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A 2 MHz 1 V programmable gain amplifier for WSN application

A 2 MHz 1 V programmable gain amplifier for WSN application

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2013 IEEE International Conference on Signal Processing, Communications and Computing, ICSPCC 2013

作者： Chengsi, Yang Zhiqun, Li Institute of RF- and OE-ICs Southeast University Nanjing China Engineering Research Center of RF-ICs and System Ministry of Education Nanjing China Key Laboratory of Sensor Network Technology of Jiangsu Province Wuxi China

ISBN: (纸本)9781479910274

This paper presents a low-voltage and low-power programmable gain amplifier (PGA) for Wireless sensor network (WSN) in 0.18 μm CMOS process. MOSFETs biased to moderate inversion region are applied in order to achieve maximum voltage gain, low device dissipation, and high linearity, simultaneously. The proposed PGA consists of three fixed-gain stages and a variable-gain stage. It works at 2 MHz with a voltage gain range of 0 dB to 70 dB in steps of 2 dB. Postsimulation results show that the -3 dB-bandwidth is higher than 6.6 MHz with capacitive loads of 2 pF. The whole PGA consumes less than 1.26 mW with a 1 V supply. © 2013 IEEE.

关键词： Wireless sensor networks

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Sparsity-Based Direct Location Estimation Based on Two-step Dictionary Learning

Sparsity-Based Direct Location Estimation Based on Two-step ...

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The 9th International Conference on Wireless Communications,networking and Mobile Computing(WICOM 2013)

作者： Tingting Wang Wei Ke Gang Liu The Jiangsu Engineering Center of Meteorological Sensor Network Technology Nanjing University of Information Science and Technology The Jiangsu Key Laboratory on Optoelectronic Technology School of Physics and TechnologyNanjing Norm University Key Laboratory of Disaster Reduction and Emergency Response Engineering of the Ministry of Civil Affairs

This paper proposes an adaptive sparsity-based direct position determination (DPD) appoach to locate multiple targets in the case of time-varying channels. The novel feature of this method is to dynamically adjust both the overcomplete basis and the sparse solution based on a two-step dictionary learning (DL) framework. The method first performs supervised offline DL by using the quadratic programming approach, and then the dictionary is continuously updated in an incremental fashion to adapt to the time-varying channel during the online stage. Furthermore, the method does not need the number of emitters a prior. Simulation results demonstrate the performance of the proposed algorithm on the location estimation accuracy.

关键词： Dictionary Learning Compressive Sensing Direct Location Time-Varying Channel Quadratic Programming

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An Energy-Efficient Asynchronous MAC for Bulk-Data Collection in Wireless sensor networks

An Energy-Efficient Asynchronous MAC for Bulk-Data Collectio...

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International Conference on Cyber-Enabled Distributed Computing and Knowledge Discovery, CyberC

作者： Fulong Jiang Hao Liu National ASIC System Engineering Research Center Southeast University Nanjing China Jiangsu Provincial Key Laboratory of Sensor Network Technology Southeast University in Wuxi Wuxi China

ISBN: (纸本)9781479913275

In this paper, we propose a new asynchronous MAC protocol, the AW-MAC, for bulk-data collection in wireless sensor networks. We develop a routing-enhanced adaptive wakeup mechanism and an on-demand channel assignment scheme that allow the protocol to transform from single channel asynchronous schedule to multi-channel TDMA schedule in an on-demand fashion. These schemes overcome the sleep latency problem of duty-cycling and avoid the inefficiency of unscheduled asynchronous channel access. The simulation results show that our protocol largely reduces the latency on collecting bulk data then the state-of-the-art asynchronous duty-cycle MAC protocol while consuming similar energy.

关键词： Media Access Protocol Wireless sensor networks Packet loss Schedules Receivers

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Sparsity-Based Direct Location Estimation Based on Two-step Dictionary Learning

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Communications and network 2013年第3期5卷 421-425页

作者： Tingting Wang Wei Ke Gang Liu The Jiangsu Engineering Center of Meteorological Sensor Network Technology Nanjing University of Information Science and Technology Nanjing China The Jiangsu Key Laboratory on Optoelectronic Technology School of Physics and Technology Nanjing Norm University Nanjing China Key Labortory of Disaster Reduction and Emergency Rseponse Engineering of the Ministry of Civil Affairs Beijing Chinaa The Jiangsu Key Laboratory on Optoelectronic Technology School of Physics and Technology Nanjing Norm University Nanjing China The Jiangsu Key Laboratory on Optoelectronic Technology School of Physics and Technology Nanjing Norm University Nanjing China Key Laboratory of Disaster Reduction and Emergency Response Engineering of the Ministry of Civil Affairs Beijing China

关键词： Dictionary Learning Compressive Sensing Direct Location Time-Varying Channel Quadratic Programming

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Adaptive Rake receiver joined with chip equalization for DS-CDMA UWB systems over ISI channels

Adaptive Rake receiver joined with chip equalization for DS-...

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2012 International Workshop on Information and Electronics engineering, IWIEE 2012

作者： Wang, Feng Jiangsu Technology and Engineering Center of Meteorological Sensor Network Nanjing University of Information Science and Technology Nanjing 210044 China

Since there is much larger channel delay spread, there is serious inter-symbol interference (ISI) when ultrawideband (UWB) wireless communication systems work at high data speed. The serious ISI affects the performance of UWB systems seriously. In this paper, a scheme to suppress ISI is developed for direct sequence spread-code division multiple access (DS-CDMA) UWB systems with a high data speed and an adaptive joint chip equalization Rake (AJCE-Rake) receiver is proposed. The proposed AJCE-Rake receiver spreads the number of traditional Rake receiver taps to collect multi-path component and equalize the inter-chip interference simultaneously. Then the soft output of AJCE-Rake receiver is despreaded with the user's spreading code. Finally, the decision is made to recover the transmitted symbol. The simulation results verify that ISI is suppressed effectively and the system performance is improved evidently. © 2011 Published by Elsevier Ltd.

关键词： Code division multiple access

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Wideband tri-band filter design using stepped-impedance stub resonators

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International Journal of Hybrid Information technology 2013年第5期6卷 249-254页

作者： Cui, Mengmeng Liu, Yun Xue, Shengjun Wang, Jin Jiangsu Engineering Center of Network Monitoring Nanjing University of Information Science and Technology Nanjing China School of Applied Meteorological Science Nanjing University of Information Science and Technology Nanjing China College of Electronic and Information Engineering Nanjing University of Aeronautics and Astronautics Nanjing China

This letter presents a wideband tri-passband filter in which tri-section stepped-impedance shunt-stubs are used as tri-mode resonators, connected by transmission lines. Developed from the topology of quarter-wavelength stub filters, these filters have much wider passbands compared to many other designs published. The stepped-impedance stubs also contribute transmission zeros between the passbands, thus increasing the isolation. A prototype filter with passbands located at 0.6-1, 1.5-1.8 and 2.2-2.4 GHz is designed by an optimization method. Good agreement between simulation and measurements in respect of low insertion loss and high isolation is demonstrated. © 2013 SERSC.

关键词： Bandpass filters

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0.18μ m cmos low voltage power amplifier for wsn application

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Telkomnika - Indonesian Journal of Electrical engineering 2013年第8期11卷 4470-4476页

作者： Chenjian, Wu Zhiqun, Li Nan, Yao Meng, Zhang Liang, Chen Jia, Cao Institute of RF- and OE-ICs Southeast University Engineering Research Center of RF-ICs and RF-Systems Ministry of Education Southeast University Nanjing 210096 China Jiangsu Provincial Key Laboratory of sensor network technology Wuxi 214135 China

This paper presents the design of a Class A/B power amplifier (PA) for 2.4-2.4835GHz Wireless sensor network (WSN) system in 0.18μm CMOS technology. The PA adopts the single-stage differential structure and the output power of the PA can be controlled by switching the sizes of transistors. Seven different level of output power can be obtained through a three-bit control code. The tested results shows that the proposed PA achieves power added efficiency (PAE) of 26.73% while delivering an output power of 6.35dBm at 1dB compression point. Its power gain is 15.87dB. With a low DC voltage supply of 1V, its power consumption is 15.3mW. The PA die size is 1070×610μm2. © 2013 Universitas Ahmad Dahlan.

关键词： Wireless sensor networks

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Research on short-term wind farm output power prediction model based on meteorological data collected by WSN

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International Journal of Hybrid Information technology 2013年第5期6卷 219-226页

作者： Ma, Li Li, Bo Jie, Du Shen, Jian Wang, Jin Jiangsu Engineering Center of Network Monitoring Nanjing University of Information Science and Technology Nanjing 210044 China School of Computer and Software Nanjing University of Information Science and Technology Nanjing 210044 China Key Laboratory of Meteorological Disaster of Ministry of Education Nanjing University of Information Science and Technology Nanjing 210044 China

The prediction of wind farm output power is considered as an effective way to increase the wind power capacity and improve the safety and economy of power system. It is one of the hot research topics on wind power. The wind farm output power is related to many factors such as wind speed, temperature, etc., which is difficult to be described by some mathematical expression. In this paper, Back Propagation (BP) neural network algorithm and genetic algorithm (GA) are combined to establish the prediction model of the short-term wind farm output power based on meteorological data collected by Wireless sensor network (WSN). The meteorological data is used to determine the input variables of the BP neural network. Meanwhile, the GA is used to adjust the value of BP's connection weight and threshold dynamically. Then the trained BP neural network is used to predict the wind power. The experiment results show that our method has better prediction capability compared with that using BP neural network alone or using wind power formulas. © 2013 SERSC.

关键词： Wireless sensor networks

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