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Answer Extraction Based on Merging Score Strategy of Hot Terms

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Chinese Journal of Electronics 2016年第4期25卷 614-620页

作者： LE Juan zhang chunxia NIU Zhendong School of Computer Science and Technology Beijing Institute of Technology School of Software Beijing Institute of Technology Beijing Engineering Research Center of Massive Language Information Processing and Cloud Computing Application Beijing Institute of Technology

Answer extraction(AE) is one of the key technologies in developing the open domain Question & answer(Q&A) *** task is to yield the highest score to the expected answer based on an effective answer score *** introduce an answer extraction method by Merging score strategy(MSS) based on hot *** hot terms are defined according to their lexical and syntactic features to highlight the role of the question *** cope with the syntactic diversities of the corpus,we propose four improved candidate answer score *** of them is based on the lexical function of hot terms and their syntactic relationships with the candidate *** independent corpus score algorithms are proposed to tap the role of the corpus in ranking the candidate *** algorithms are adopted in MSS to tap the complementary action among the corpus,the candidate answers and the *** demonstrate the effectiveness of the proposed strategy.

关键词： Question & answer(Q&A) Answer extraction(AE) Merging score strategy(MSS) Hot terms

Glacial-interglacial cycles recorded in clay minerals from the eastern Tibetan Plateau over the last 800 ka and their indications

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Science China Earth Sciences 2024年第7期67卷 2162-2177页

作者： Xiaoyan zhang chunxia zhang Yan ZHAO Bin HU Zhengtang GUO Key Laboratory of Cenozoic Geology and Environment Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029China College of Earth and Planetary Sciences University of Chinese Academy of SciencesBeijing 100049China College of Earth Science and Engineering Shandong University of Science and TechnologyQingdao 266590China Key Laboratory of Land Surface Pattern and Simulation Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing 100101China

Clay mineral proxies have been widely used to reconstruct changes in provenance and the ***,high-altitude clay mineral indications and long-term and orbital variations have not been fully ***,we present an800-ka clay-mineral record from a lacustrine sediment core(ZB13-C2)from the Zoige Basin on the eastern Tibetan Plateau(TP).X-ray diffraction and scanning electron microscopy were used to identify the clay mineral assemblages and their micromorphological characteristics of core *** results revealed that the clay minerals in core ZB13-C2 are mainly illite,with small amounts of chlorite,kaolinite,and smectite(including irregular mixed-layers of illite-smectite(I/S)and chloritesmectite(C/S)).The clay mineral assemblages and proxies exhibit three stages of change,which are mainly controlled by the Zoige watershed range under different climate *** watershed was limited to the southeastern region with altitudes ranging from~3500 to~4200 meters above sea level(m a.s.l.),and glacial-interglacial hydraulic erosion controlled the input of bedrock debris during 800-621 ka *** expanded to higher altitudes(~4200 to~4700 m a.s.l.)due to stronger seasonal freezethaw weathering without significant glacial-interglacial variations under a cooling and drying climate during 621-100 ka ***,it expanded to its highest altitudes of~4700 to~5200 m *** of the watershed after 100 ka BP,and hydraulic erosion increased obviously under a warm climate of the interstadial MIS 3 on the *** watershed underwent two major expansions under different climatic conditions at~621 ka and 100 ka BP,with the wet/dry alternation became strong at~621 ka *** results reveal that long-term temperature changes and the wet/dry alternation at high altitudes controlled the watershed range and degree of the physical erosion,and that the indications of clay minerals should be carefully clarified before they are used as climate indicators,especi

关键词： Quaternary Zoige Basin Lacustrine sediments Paleoenvironment Weathering

Shallow subsurface habitats across the Mars-analog Qaidam Basin

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Science China Earth Sciences 2023年第11期66卷 2487-2496页

作者： Yan CHEN Li LIU Huiqing zhang Xue GUO Wensi zhang chunxia zhang Wei LIN Key Laboratory of Earth and Planetary Physics Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029China College of Earth and Planetary Sciences University of Chinese Academy of SciencesBeijing 100049China Department of Clinical Laboratory National Clinical Research Center for Infectious DiseaseShenzhen Third People’s HospitalShenzhen 518112China State Key Laboratory of Microbial Resources Institute of MicrobiologyChinese Academy of SciencesBeijing 100101China Key Laboratory of Cenozoic Geology and Environment Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029China

Searching for life is one of the most important targets of Mars exploration missions. It has been considered that the Martian subsurface, away from the extreme surface environment, is a potentially habitable region for microbial ***, the distribution pattern of potential microbial habitats in the Martian subsurface has yet to be evaluated. Here, we investigate the subsurface habitats to depths of 20–60 cm from various landscapes, including slopes, gullies, channels, playas,and alluvial fans across the Mars-analog Qaidam Basin, NW China. We characterize subsurface niches by measuring microbial biomass and radiocarbon ages, and correlate them with soil properties including depth, moisture content, total organic carbon content, electric conductivity, pH, evaporite and clay mineral contents. We find more habitable niches for microbial colonization at depths of 5–25 cm as compared with the surface and deep subsurface across the hyperarid Qaidam Basin. Maximum biomass and biotic activity could be correlated with physical stability, limited radiation, and short-term moderate water availability in the shallow subsurface in hyperarid deserts. The findings of this study provide new perspectives on subsurface microbial habitats in Mars-analog hyperarid deserts and ongoing biosignature detection on Mars.

关键词： Mars-analog Qaidam Basin Shallow subsurface Microbial habitat Astrobiology

Clay mineralogy of an Eocene fluvial-lacustrine sequence in Xining Basin, Northwest China, and its paleoclimatic implications

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Science China Earth Sciences 2019年第3期62卷 571-584页

作者： Bin HU chunxia zhang Haibin WU Qingzhen HAO Zhengtang GUO Key Laboratory of Cenozoic Geology and Environment Institute of Geology and Geophysics Chinese Academy of Sciences Institution of Earth Science Chinese Academy of Science College of Earth Science and Engineering Shandong University of Science and Technology CAS Center for Excellence in Life and Paleoenvironment University of Chinese Academy of Sciences

The Eocene was marked by significant cooling during which the global climate was transformed from greenhouse to icehouse conditions. Notable coeval events were the India-Asia collision and the retreat of the Paratethys Sea in Asia. The Eocene section of the long and continuous sedimentary succession of the Xining Basin in Northwest China is characterized by red mudstones with intercalated gypsum and muddy-gypsiferous layers. In this study, we conducted a semi-quantitative analysis of the mineralogy of bulk samples and the clay fraction using X-ray diffraction, with the aim of characterizing the Eocene climatic evolution of the northeastern margin of the Tibetan Plateau and inland Asia. We used a new pretreatment method to address the problem of extracting sufficient clay particles from the gypsum and gypsiferous layers. The bulk mineralogy is dominated by quartz, feldspar, calcite, gypsum and dolomite; and the clay mineralogy is dominated by illite, chlorite, and smectite(including irregular mixed-layer illite-smectite(I/S)). The variations of the clay mineral assemblages indicate the occurrence of alternations between warm humid conditions and hot dry conditions, with relatively high humidity during ～52–50,～41.5–39 and ～35–34 Ma. Comparison of the results with the timing of Tibetan Plateau uplift, transgressions and regressions of the Paratethys Sea, and the marine oxygen isotope record suggest that the Eocene climatic evolution of the study region was driven fundamentally by global climate change.

关键词： Eocene Xining Basin Clay minerals Paleoclimate

Polymer Solar Cells with Improved Power Conversion Efficiency Using Solvent Mixtures

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Chemical Research in Chinese Universities 2017年第3期33卷 466-470页

作者： zhang chunxia XU Xu zhang Panpan DANG Yang KANG Bonan State Key Laboratory on Integrated Optoelectronics College of Electronic Science and Engineering Jilin University Changchun 130012 P. R. China

In this paper, the effects of solvent mixtures on the morphology, charge transport, and light trapping of poly[N-900-hepta-decanyl-2,7-carbazole-alt-5,5-（40,70-di-2-thienyl-20,10,30-benzothiadiazole）]（PCDTBT） and [6,6]-phenyl C71-butyric acid methyl ester（PC71BM） based solar cells were investigated. As a good solvent for PCDTBT, o-dichlorobenzene（ODCB） was selected to mix with chloroform（CF）, chlorobenzene（eB）, and 1,2,4-Trichloroben-zene（TCB） for optimizing the morphology of the PCDTBT：PCTIBM active layer. It can be found that the device performance of polymer solar cells（PSCs） has been greatly improved when using a optimal blend ratio. Especially, the PSCs fabricated via ODCB（90%）/CF（10%, volume fraction） mixture exhibit a remarkable enhancement of photon-to-current efficiency（PCE） from 5.16% to 7.47%. The enhanced performance of the PSCs can be attributed to the higher absorption, the lower resistance, and the optimized surface morphology of the active layers modified by the solvent mixtures.

关键词： Solvent mixture Phase separation Electron transport Morphology Polymer solar cell

Cross-Modal Complementary Network with Hierarchical Fusion for Multimodal Sentiment Classification

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Tsinghua Science and Technology 2022年第4期27卷 664-679页

作者： Cheng Peng chunxia zhang Xiaojun Xue Jiameng Gao Hongjian Liang Zhengdong Niu School of Computer Science and Technology Beijing Institute of TechnologyBeijing 100081China School of Information Production and SystemsWaseda UniversityFukuoka 808-0135Japan

Multimodal Sentiment Classification(MSC)uses multimodal data,such as images and texts,to identify the users'sentiment polarities from the information posted by users on the *** has attracted considerable attention because of its wide applications in social computing and opinion ***,improper correlation strategies can cause erroneous fusion as the texts and the images that are unrelated to each other may ***,simply concatenating them modal by modal,even with true correlation,cannot fully capture the features within and between *** solve these problems,this paper proposes a Cross-Modal Complementary Network(CMCN)with hierarchical fusion for *** CMCN is designed as a hierarchical structure with three key modules,namely,the feature extraction module to extract features from texts and images,the feature attention module to learn both text and image attention features generated by an image-text correlation generator,and the cross-modal hierarchical fusion module to fuse features within and between *** a CMCN provides a hierarchical fusion framework that can fully integrate different modal features and helps reduce the risk of integrating unrelated modal *** experimental results on three public datasets show that the proposed approach significantly outperforms the state-of-the-art methods.

关键词： multimodal sentiment analysis multimodal fusion Cross-Modal Complementary Network(CMCN) hierarchical fusion joint optimization

Formation of β-Lactones by [2＋2] Cycloaddition of Dichloroketene with Unreactive Carbonyl Compounds

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Chemical Research in Chinese Universities 2018年第5期34卷 736-743页

作者： DONG Xu zhang chunxia XU Jian zhang Yue ZHAO Ying CHEN Li State Key Laboratory and Institute of Elemento-Organic Chemistry College of Chemistry Nankai University Tianjin 300071 P. R. China

We report a modified process that dichloroketene generated in situ from trichloroacetyl chloride and Zn powder reacts with unreactivate carbonyl groups to afford dichloro-β-lactones in moderate to good yields. Subse- quently, monochloro-β-lactones, β-lactones and β-hydroxy ester are obtained by dechlorination under different reac- tion conditions.

关键词： Dichloroketene Unreactive carbonyl group β-Lactone [2+2] Cycloaddition

An Improved Hybrid Collaborative Filtering Algorithm Based on Tags and Time Factor

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Big Data Mining and Analytics 2018年第2期1卷 128-136页

作者： chunxia zhang Ming Yang Jing Lv Wanqi Yang the School of Computer Science and Technology Nanjing Normal University

The Collaborative Filtering(CF) recommendation algorithm, one of the most popular algorithms in Recommendation Systems(RS), mainly includes memory-based and model-based methods. When performing rating prediction using a memory-based method, the approach used to measure the similarity between users or items can significantly influence the recommendation performance. Traditional CFs suffer from data sparsity when making recommendations based on a rating matrix, and cannot effectively capture changes in user interest. In this paper, we propose an improved hybrid collaborative filtering algorithm based on tags and a time factor(TTHybridCF), which fully utilizes tag information that characterizes users and items. This algorithm utilizes both tag and rating information to calculate the similarity between users or items. In addition, we introduce a time weighting factor to measure user interest, which changes over time. Our experimental results show that our method alleviates the sparsity problem and demonstrates promising prediction accuracy.

关键词： recommendation system similarity tag time factor

Global convergence in correlations among soil properties

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International Journal of Agricultural and Biological Engineering 2020年第3期13卷 108-116页

作者： Baicheng Xie chunxia zhang Guodong Wang Yingge Xie College of Science Northwest A&F UniversityYangling 712100ShaanxiChina Institute of Meteorology Science of Hunan Province Changsha 410118China Meteorological Disaster Prevention and Mitigation Key Laboratory of Hunan Province Changsha 410118China Changsha Environmental Protection College Changsha 410004China

The correlations among major soil properties at a global scale are essential for explaining the global convergence of ecological processes in terrestrial ecosystems but have never been *** this study,a global soil database was analyzed to determine whether correlations among soil properties were consistent and how such correlations varied among continents and land use *** the entire dataset,the electrical conductivity of soils increased significantly with increasing pH;additionally,the total nitrogen and cation exchange capacity increased significantly with increasing organic carbon content,while the organic carbon content and cation exchange capacity decreased significantly with increasing sand content in *** correlations between paired soil properties were consistent among continents and land use *** slopes of the relationships,however,varied significantly by continent and land use *** results indicated a global convergence of correlations among soil properties and variation in the slopes of specific relationships between paired soil properties among continents and land use *** consistent global correlations and different slopes of specific correlations can have important implications in explaining the global patterns of biogeochemical processes and can provide some basis for linking soil resources with ecological processes on a global scale.

关键词： continent land use organic carbon electricity pH CEC