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Transfer synthetic over-sampling for class-imbalance learning with limited minority class data

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Frontiers of Computer Science 2019年第5期13卷 996-1009页

作者： Xu-Ying LIU Sheng-Tao WANG Min-Ling ZHANG School of Computer Science and Engineering Southeast University Nanjing 210096 China Key Laboratory of Computer Network and Information Integration (Southeast University) Ministry of Education Nanjing 210096 China Collaborative Innovation Center for Wireless Communications Technology Nanjing 210096 China

The problem of limited minority class data is encountered in manyclass imbalanced applications, but has received little attention. Synthetic over-sampling, as popular class-imbalance learning methods, could introduce much noise when minority class has limited data since the synthetic samples are not i.i.d. samples of minority class. Mos t sophisticated synthetic sampling methods tackle this problem by denoising or generating samples more consistent with ground-truth data distribution. But their assumptions about true noise or ground-truth data distribution may not hold. To adapt synthetic sampling to the problem of limited minority class data, the proposed Traso framework treats synthetic minority class samples as an additional data source, and exploits transfer learning to transfer knowledge from them to minority class. As an implementation, TrasoBoost method firstly generates synthetic samples to balance class sizes. Then in each boosting iteration, the weights of synthetic samples and original data decrease and increase respectively when being misclassified, and remain unchanged otherwise. The misclassified synthetic samples are potential noise, and thus have smaller influence in the following iterations. Besides, the weights of minority class instances have greater change than those of majority class instances to be more influential. And only original data are used to estimate error rate to be immune from noise. Finally, since the synthetic samples are highly related to minority class, all of the weak learners are aggregated for prediction. Experimental results show TrasoBoost outperforms many popular class-imbalance learning methods.

关键词： machine learning data mining class imbalance over sampling boosting transfer learning

Coherent Transfer of Optical Frequency over 112 km with Instability at the 10^(-20) Level

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Chinese Physics Letters 2016年第11期33卷 47-49页

作者：邓雪刘杰焦东东高静臧琦许冠军董瑞芳刘涛张首刚 National Time Service Centre Chinese Academy of Sciences Key Laboratory of Time and Frequency Standards Chinese Academy of Sciences University of Chinese Academy of Sciences

We demonstrate optical-carrier transfer over a 112-km single-span urban fiber link, By actively compensating the phase noise induced along the fiber link, a noise suppression of 55 dB at 1 Hz is obtained. A fractional frequency instability of 2.5× 10^-16 at i s is achieved, and reaching 7.5× 10^-20 at 10000 s. The system is stable and able to run for a long time. This work will contribute to optical frequency distribution and remote comparison among atomic clocks.

关键词： of is as link Coherent Transfer of Optical Frequency over 112 km with Instability at the 10 Level with over

New Evidences for the Adsorption of Methane over Oxide Surfaces

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Chinese Chemical Letters 1996年第9期7卷 875+873-874页

作者： Fa Qiang XU Shi Kong SHEN Jin Zhen XUE(National Synchrotron Radiation Laboratory.University of Science and Technology of China.Hefei 230029.)(Key State Laboratory for Oxo Synthesis and Selective Oxidation. Lanzhou Institute of Chemical Physics.Chinese Ac Natl. Synchrt. Radiation Laboratory Univ. of Sci./Technology of China Hefei 230029 Key State Lab. Oxo Synthesis/S. O. Lanzhou Inst. of Chemical Physics Chinese Academy of Sciences Lanzhou 730000

It is indicative of the TSR result that CH4 was strongly adsorbed on well degassed SrCO3 surface at high temperatUre.A desorption peak of CH4 was found in CH4TPD profile which appeared at ca. 310℃.The strong adsorption of CH4 over the surface of SrCO3 was attributed to the strong basicity of SrO sites resulted from decomposition of SrCO_3

关键词： over New Evidences for the Adsorption of Methane over Oxide Surfaces

Polarization multiplexing based duplex radio-over-fiber link for millimeter wave signal transmission to a ring of multiple radio access units

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Frontiers of Information Technology & Electronic Engineering 2019年第2期20卷 300-306页

作者： Tayyab MEHMOOD Hina QAYYUM Salman GHAFOOR School of Electrical Engineering and Computer Science National University of Sciences and Technology

A radio-over-fiber(RoF) distributed antenna system(DAS) architecture is proposed, where millimeter wave(mm-wave) signals are transmitted to four different radio access units(RAUs) arranged in a ring *** proposed architecture transmits duplex data of 128 Mb/s to each RAU in both downlink(DL) and uplink(UL)directions. The radio frequency(RF) signals are transmitted by polarization multiplexing a multi-wavelength ***-wave signals at a frequency of 25 GHz are generated at each RAU using remote heterodyne *** proposed architecture provides increased coverage while maintaining good bit error rate(BER) results.

关键词： Radio over fiber Millimeter wave Radio access units

Seasonal variability of cirrus depolarization properties derived from CALIPSO lidar measurements over Beijing in China

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Chinese Optics Letters 2010年第2期8卷 127-129页

作者：路小梅江月松张绪国周波欧军 School of Electronics and Information Engineering Beihang University

The seasonal variability of cirrus depolarization ratio and its altitude at the region of Beijing （39.93°N, 116.43°E, the capital of China） are presented. From the results obtained from the cloud aerosol lidar and infrared pathfinder satellite observations lidar measurements, it appears that the values of depolarization ratio and altitude of cirrus are generally higher in autumn and summer than those in spring and winter, and the cirrus altitude is modulated by the height of tropopause. Additionally, the depolarization ratio tends to linearly vary with the increase of altitude and the decrease of temperature.

关键词： CALIPSO Seasonal variability of cirrus depolarization properties derived from CALIPSO lidar measurements over Beijing in China over

A query on the year of King Wu's conquest over King Zhou determined by the Xia-Shang-Zhou Chronology Project -Materials finding and astronomical methods for chronological studies of China

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Science China(Physics,Mechanics & Astronomy) 2003年第5期46卷 481-491页

作者：李勇 National Astronomical Observatories Chinese Academy of Sciences Beijing 100012 China

This paper reviews the studies on the event that King Wu of the Western Zhou Dynasty defeated King Zhou of the late Shang Dynasty, an important historical event in Chinese history, and questions on the year in which this event took place determined by researchers of the Xia-Shang-Zhou Chronology Project of China in 2000. This paper also discusses on how to obtain primordial materials and how to use astronomical methods in the chronological studies of Chinese history. With both the new astronomical methods (the Moon Age Calendar Method and the Direct Solving Method) and the calculation based on the confirmed real-time materials, especially scriptures on oracle bones and bronze vessels, this paper obtains a more accurate and reliable result, putting the event at BC 1040 to BC 1030.

关键词： ephemeris, astronomical chronology, King Wu's conquest over King Zhou.

Polynomial Splitting Ring and Root Representation of Linear Recurring Sequences over Z|(p^e)

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Science China Mathematics 1994年第9期37卷 1047-1052页

作者：戚文峰周锦君 Department of Applied Mathematics Zhengzhou Information Engineering Institute Zhengzhou 450002 PRC

The concept of the splitting ring of the polynomial over ring Z(pe) is introduced and the factomation of polynomials and the properties df polynomial roots are discussed. By using these results and the structure of sequence families, it is shown that the terms of a linear recurring sequence over Z/(pe) may be represented by the roots of its characteristic polynomial and the representation is uniquely determined by the sequence.

关键词： splitting ring over Z|(p^e) linear recurring sequence root representation of sequences.

Impact of Optical Hop Constraints on the IP/MPLS-over-WSON Networks CAPEX

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China Communications 2015年第11期12卷 112-118页

作者： LIU Fengqing Jaume Comellas School of Opto-Electronic Engineering Nanjing University of Posts and Telecommunications Dept.of Signal Theory and Communications Universitat Politècnica de Catalunya Barcelona

In this work,the impact of hop constraints on the CAPEX of multi-layer IP/MPLS over WSON networks is evaluated under different scenarios. By routing lightpaths with different number of transparent hops,the cost of networks varies significantly. This effect is thoroughly analyzed with a heuristic algorithm for different network topologies belonging to some European network operators. The main conclusion extracted is that limiting the transparent reach in such multi-layer networks can give a good tradeoff between CAPEX of IP/MPLS networks and WSON networks,and even lead to signifi cant savings in CAPEX when compared to longer lightpaths routing strategies.

关键词： IP/MPLS over WSON networks optical hop constraints CAPEX heuristics

OXIDATIVE　METHYLATION　OF　TOLUENE　WITH　METHANE　over　BASIC　ZEOLITE　CATALYSTS　PROMOTED　WITH　ALKALI　METAL　OXIDES

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Chinese Chemical Letters 1996年第3期7卷 229-232页

作者： Zhou, LP Tao, KY Li, W Su, M Li, HX Hattori, H HOKKAIDO UNIV SAPPOROHOKKAIDO 060JAPAN NANKAI UNIV DEPT CHEMTIANJIN 300071PEOPLES R CHINA

The oxidative methylaion of tolucoe with methane to ethylbenzene and Styrene proCeeded over basic Y typezeolite catalyst at 1023K. KY was prepared from NaY raw powder by exchange with 0.5M KOH aqueoussolution at 363K. Loaded KY were preped by impregnating aqueous solutions of LiNO3 and CsNO3 onto *** KY zeolite showed very low C8-yield and selativity. Addition of alkali-metal oxides to the KYzeolite increased greatly the catalytic activity. The Cs2O(6Wt% Cs2O)/KY catalyst gave the highest C3 yield of32.2% with selelectivity of 60.9%.

关键词： BASIC PROM CATA over