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Distributed and Weighted Extreme Learning Machine for Imbalanced Big Data Learning

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Tsinghua Science and Technology 2017年第2期22卷 160-173页

作者： Zhiqiong Wang Junchang Xin Hongxu Yang Shuo Tian ge yu Chenren Xu yudong Yao the Sino-Dutch Biomedical & Information Engineering School Northeastern UniversityShenyang 110169China the School of Computer Science & Engineering Northeastern UniversityShenyang 110169China the School of Electronics Engineering and Computer Science Peking UniversityBeijing 100871China the Department of Electrical and Computer Engineering Stevens Institute of TechnologyCastle Point on Hudson HobokenNJ 07030USA.

The Extreme Learning Machine（ELM） and its variants are effective in many machine learning applications such as Imbalanced Learning（IL） or Big Data（BD） learning. However, they are unable to solve both imbalanced and large-volume data learning problems. This study addresses the IL problem in BD applications. The Distributed and Weighted ELM（DW-ELM） algorithm is proposed, which is based on the Map Reduce framework. To confirm the feasibility of parallel computation, first, the fact that matrix multiplication operators are decomposable is ***, to further improve the computational efficiency, an Improved DW-ELM algorithm（IDW-ELM） is developed using only one Map Reduce job. The successful operations of the proposed DW-ELM and IDW-ELM algorithms are finally validated through experiments.

关键词： weighted Extreme Learning Machine(ELM) imbalanced big data MapReduce framework user-defined counter

Stretch bending defect control of L-section SUS301L stainless-steel components with variable contour curvatures

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Journal of Iron and Steel Research International 2019年第12期26卷 1376-1384页

作者： Zheng-wei Gu Lei Jia Xin Li Li-juan Zhu Hong Xu ge yu Department of Materials Science and Engineering Jilin UniversityChangchun 130022JilinChina Roll Forging Research Institute Jilin UniversityChangchun 130022JilinChina

The stretch bending of L-section variable-curvature SUS301L stainless-steel roof bending beams for metro vehicles was numerically *** causes of defects such as wrinkling,section distortion,and poor contour accuracy were analysed,and the corresponding control methods were *** simulation results demonstrated that wrinkling in the small-arc segment could be eliminated by setting the die clearance and adjusting the elongation *** to the sidewall shrinkage of the profile in the process of stretch bending,the die groove depth was correspondingly *** section of the profile was effectively supported by the bottom of the die groove,and the section distortion could be *** was the main reason for the poor contour accuracy,which could be compensated by modifying the die surface based on the springback *** the above defect control methods,forming experiments were performed on a new type of stretch bending die with variable die clearance and groove depth developed in this ***,high-quality components were obtained,which verified the efficacy of the defect control methods.

关键词： Stretch bending L-section Variable contour curvature Stainless-steel profile Defect control

Preliminary reconstruction of spatial precipitation patterns and atmospheric circulations in China during the late Quaternary

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维普期刊数据库

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Chinese Science Bulletin 2001年第S1期46卷 22-27页

作者： XUE Bin yu ge WANG Sumin LIU Jian CHEN Xing Nanjing Insititute of geography and Limnology Nanjing 210008China Department of Atmospheric Sciences Nanjing UniversityNanjing 210093China

Quantitative estimates of the precipitation on different lake sites at the three time phases, i.e. 30, 18, and 6 kaBP by using the combined hydrological and energy budget model, make it possible to reconstruct the large changes in spatial precipitation patterns since the late Quaternary. The results have shown that, very strong precipitation occurred in western China at 30 kaBP, suggesting extremely enhanced summer Indian monsoon. Precipitation was high in southwestern China at 18 kaBP, especially the southern part of southwestern China, due to the southward shift of the westerlies and a low pressure cell occurred over northern India. The precipitation at 6 kaBP shows the complicated patterns for different regions of China, suggesting different climate dynamics. The comparison of the independent lake level/ area-based reconstruction of precipitation and the palaeo-climate simulations is an effective way for the validation ofeach method to reconstruct the palaeo-precipitation quantitatively, and for

关键词： precipitation patterns atmospheric circulation late Quaternary China.

Semantic movie summarization based on string of IE-Role Nets

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Computational Visual Media 2015年第2期1卷 129-141页

作者： Wen Qu Yifei Zhang Daling Wang Shi Feng ge yu School of Information Science and Engineering Northeastern University Key Laboratory of Medical Image Computing(Northeastern University) Ministry of Education

Roles, their emotion, and interactions between them are three key elements for semantic content understanding of movies. In this paper, we proposed a novel movie summarization method to capture the semantic content in movies based on a string of IE-Role Nets. An IE-Role Net(interaction and emotion rolenet) models the emotion and interactions of roles in a shot of the movie. The whole movie is represented as a string of IE-Role Nets. Summarization of a movie is transformed into finding an optimal substring with user-specified summarization *** substring mining is conducted to find an optimal substring of the whole movie. We have conducted objective and subjective experiments on our method. Experimental results show the ability of our method to capture the semantic content of movies.

关键词： movie summarization content analysis movie understanding

Modeling Chinese Microblogs with Five Ws for Topic Hashtags Extraction

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Tsinghua Science and Technology 2017年第2期22卷 135-148页

作者： Zhibin Zhao Jiahong Sun Lan Yao Xun Wang Jiahong Chu Huan Liu ge yu College of Computer Science and Engineering Northeastern University

Hashtags are important metadata in microblogs and are used to mark topics or index messages. However,statistics show that hashtags are absent from most microblogs. This poses great challenges for the retrieval and analysis of these tagless microblogs. In this paper, we summarize the similarity between microblogs and shortmessage-style news, and then propose an algorithm, named 5WTAG, for detecting microblog topics based on a model of five Ws（When, Where, Who, What, ho W）. As five-W attributes are the core components in event description, it is guaranteed theoretically that 5WTAG can properly extract semantic topics from microblogs. We introduce the detailed procedure of the algorithm in this paper including spam microblog identification, microblog segmentation, and candidate hashtag construction. In addition, we propose a novel recommendation computing method for ranking candidate hashtags, which combines syntax and semantic analysis and observes the distribution of artificial topic hashtags. Finally, we conduct comprehensive experiments to verify the semantic correctness and completeness of the candidate hashtags, as well as the accuracy of the recommendation method using real data from Sina Weibo.

关键词： hashtag microblog topic detection short-message-style news five Ws

Fast filtering false active subspaces for efficient high dimensional similarity processing

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Science in China(Series F) 2009年第2期52卷 286-294页

作者： WANG GuoRen yu ge, XIN JunChang ZHAO yuHai ZHANG EnDe School of Information Science and Engineering Northeastern University Shenyang 110004 China

The query space of a similarity query is usually narrowed down by pruning inactive query subspaces which contain no query results and keeping active query subspaces which may contain objects corre- sponding to the request. However, some active query subspaces may contain no query results at all, those are called false active query subspaces. It is obvious that the performance of query processing degrades in the presence of false active query subspaces. Our experiments show that this problem becomes seriously when the data are high dimensional and the number of accesses to false active subspaces increases as the dimensionality increases. In order to solve this problem, this paper proposes a space mapping approach to reducing such unnecessary accesses. A given query space can be refined by filtering within its mapped space. To do so, a mapping strategy called maxgap is proposed to improve the efficiency of the refinement processing. Based on the mapping strategy, an index structure called MS-tree and algorithms of query processing are presented in this paper. Finally, the performance of MS-tree is compared with that of other competitors in terms of range queries on a real data set.

关键词： high dimensional index refining processing false active subspace

Influence of Negative Pressure Gradient on Pressure Distribution and Gas-Solid Flow Pattern of Solid Feed Systems

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China Petroleum Processing & Petrochemical Technology 2018年第2期20卷 104-110页

作者： Zhang Meiju Pan Feng Shao Guoqiang ge yu Zhang Lei State Key Laboratory of Multi-phase Complex Systems Institute of Process EngineeringChinese Academy of Sciences

A series of experiments on a solid feed system was performed to investigate the effect of negative pressure gradient on the gas-solid flow pattern and hydrodynamic *** on the non-fluidized gas-solid two phase flow and particulate mechanics in the standpipe,a method for predicting the pressure of the air passing through the recycle chamber and the pressure drop through the loop seal slit in these systems is also *** predicted pressure profile along the negative pressure gradient from the proposed model exhibits a good agreement with the experimental *** experimental data show that the gas flow in the standpipe is always upward in the negative pressure gradients,while the direction ofthe superficial gas velocity through the recycle chamber of the loop seal does not affect the pressure drop in *** increases with an increasing negative pressure gradient.

关键词： fuidized bed solid feedsystem negative pressure gradient gas-solid fow pattern

An Indexed Non-Equijoin Algorithm Based on Sliding Windows over Data Streams

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Wuhan University Journal of Natural Sciences 2006年第1期11卷 294-298页

作者： yu Ya-xin YANG Xing-hua yu ge WU Shan-shan School of Computer Science and Engineering Northeastern University Shenyang 110004 Liaoning China

Processing a join over unbounded input streams requires unbounded memory, since every tuple in one infinite stream must be compared with every tuple in the other. In fact, most join queries over unbounded input streams are restricted to finite memory due to sliding window constraints. So far, non-indexed and indexed stream equijoin algorithms based on sliding windows have been proposed in many literatures. However, none of them takes non-equijoin into consideration. In many eases, non-equijoin queries occur frequently. Hence, it is worth to discuss how to process non-equijoin queries effectively and efficiently. In this paper, we propose an indexed join algorithm for supporting non-equijoin queries. The experimental results show that our indexed non-equijoin techniques are more efficient than those without index.

关键词： non-equijoin data stream sliding window red-black indexing tree

Effects of luteinizing hormone and androgen on the development of rat progenitor Leydig cells in vitro and in vivo

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Asian Journal of Andrology 2013年第5期15卷 685-691页

作者： Jing-Jing Guo Xue Ma Claire Q F Wang yu-Fei ge Qing-Quan Lian Dianne O Hard yu-Fei Zhang Qiang Dong yun-Fei Xu Ren-Shan ge The 2nd Affiliated Hospital Wenzhou Medical College Wenzhou 325027 China Population Council & Rockefeller University New York NY 10065 USA Department of Urology West China Hospital Sichuan University Chengdu 610041 China Mudanjiang Medical College M udanjiang 157011 China Department of Urology the Affiliated 10th People's Hospital of Tongji University Shanghai 200072 China

Progenitor Leydig cells are derived from stem cells. The proliferation and differentiation of progenitor Leydig cells significantly contributes to Leydig cell number during puberty. However, the regulation of these processes remains unclear. The objective of the present study was to determine whether luteinizing hormone （LH） or androgen contributes to the proliferation and differentiation of progenitor Leydig cells. Fourteen-day-old male Sprague-Dawley rats were treated for 7 days with NalGlu, which is a gonadotropin- releasing hormone antagonist, to reduce the secretion of LH in the pituitary and thus, androgen in the testis. Rats were co-administered with LH or 7a-methyl-nortestosterone （MENT）, which is an androgen resistant to metabolism by 5a-reductase 1 in progenitor Leydig cells, and the subsequent effects of LH or androgen were measured. 3H-Thymidine was also intravenously injected into rats to study thymidine incorporation in progenitor Leydig cells. Progenitor Leydig cells were examined. NalGlu administration reduced progenitor Leydig cell proliferation by 83%. In addition, LH or MENT treatment restored Leydig cell proliferative capacity to 73% or 50% of control, respectively. The messenger RNA levels of proliferation-related genes were measured using real-time PCR. The expression levels of Igfl, Lifr, Pdgfra, Bcl2, Ccnd3and Pcnawere upregulated by MENT, and those of Pdgfra, Ccnd3and Pcnawere upregulated by LH. Both LH and MENT stimulated the differentiation of progenitor Leydig cells in vitro. We concluded that both LH and MENT were involved in regulating the development of progenitor Leydig cells.

关键词： l utei nizi ng hormone progenitor Leydig cell proliferation testosterone