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Efficient query processing framework for big data warehouse： an almost join-free approach

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Frontiers of Computer Science 2015年第2期9卷 224-236页

作者： huiju wang Xiongpai QIN Xuan ZHOU Furong LI Zuoyan QIN Qing ZHU Shan wang DEKE Lab (Renmin University of China) Beijing 100872 China School of Information Renmin University of China Beijing 100872 China School of Computing National University of Singapore Singapore 117417 Singapore

The rapidly increasing scale of data warehouses is challenging today＇s data analytical technologies. A con- ventional data analytical platform processes data warehouse queries using a star schema -- it normalizes the data into a fact table and a number of dimension tables, and during query processing it selectively joins the tables according to users＇ demands. This model is space economical. However, it faces two problems when applied to big data. First, join is an expensive operation, which prohibits a parallel database or a MapReduce-based system from achieving efficiency and scalability simultaneously. Second, join operations have to be executed repeatedly, while numerous join results can actually be reused by different queries. In this paper, we propose a new query processing frame- work for data warehouses. It pushes the join operations par- tially to the pre-processing phase and partially to the post- processing phase, so that data warehouse queries can be transformed into massive parallelized filter-aggregation oper- ations on the fact table. In contrast to the conventional query processing models, our approach is efficient, scalable and sta- ble despite of the large number of tables involved in the join. It is especially suitable for a large-scale parallel data ware- house. Our empirical evaluation on Hadoop shows that our framework exhibits linear scalability and outperforms some existing approaches by an order of magnitude.

关键词： data warehouse large scale TAMP join-free,multi-version schema

Gigantic Genomes Provide Empirical Tests of Transposable Element Dynamics Models

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Genomics, Proteomics & Bioinformatics 2021年第1期19卷 123-139页

作者： Jie wang Michael W.Itgen huiju wang Yuzhou Gong Jianping Jiang Jiatang Li Cheng Sun Stanley K.Sessions Rachel Lockridge Mueller CAS Key Laboratory of Mountain Ecological Restoration and Bioresource Utilization&Ecological Restoration and Biodiversity Conservation Key Laboratory of Sichuan Province Chengdu Institute of BiologyChinese Academy of SciencesChengdu 610041China Department of Biology Colorado State UniversityFort CollinsCO 80523USA School of Information and Safety Engineering Zhongnan University of Economics and LawWuhan 430073China Institute of Apicultural Research Chinese Academy of Agricultural SciencesBeijing 100093China Biology Department Hartwick CollegeOneontaNY 13820USA

Transposable elements(TEs)are a major determinant of eukaryotic genome *** collective properties of a genomic TE community reveal the history of TE/host evolutionary dynamics and impact present-day host structure and function,from genome to organism *** rare cases,TE community/genome size has greatly expanded in animals,associated with increased cell size and changes to anatomy and ***,we characterize the TE landscape of the genome and transcriptome in an amphibian with a giant genome—the caecilian Ichthyophis bannanicus,which we show has a genome size of 12.2 *** are an important model system because the clade includes independent cases of genomic *** *** genome differs compositionally from other giant amphibian genomes,but shares a low rate of ectopic recombination-mediated *** examine TE activity using expression and divergence plots;TEs account for 15%of somatic transcription,and most superfamilies appear *** quantify TE diversity in the caecilian,as well as other vertebrates with a range of genome sizes,using diversity indices commonly applied in community *** synthesize previous models that integrate TE abundance,diversity,and activity,and test whether the caecilian meets model predictions for genomes with high TE *** propose thorough,consistent characterization of TEs to strengthen future comparative *** analyses will ultimately be required to reveal whether the divergent TE assemblages found across convergent gigantic genomes reflect fundamental shared features of TE/host genome evolutionary dynamics.

关键词： TE expression TE diversity index Genome size evolution Caecilian Transposon ecology

Direct Climatic Effect of Dust Aerosol in the NCAR Community Atmosphere Model Version 3 (CAM3)

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Advances in Atmospheric Sciences 2010年第2期27卷 230-242页

作者：乐旭王会军廖宏范可 Climate Change Research Center Chinese Academy of Sciences Nansen-Zhu International Research Center (NZC) Institute of Atmospheric Physics Chinese Academy of Sciences Graduate University of the Chinese Academy of Sciences State Key Laboratory of Atmospheric Boundary Layer Physics and Atmospheric Chemistry Institute of Atmospheric Physics Chinese Academy of Sciences

Direct climate responses to dust shortwave and longwave radiative forcing （RF） are studied using the NCAR Community Atmosphere Model Version 3 （CAM3）. The simulated RF at the top of the atmosphere （TOA） is-0.45 W m-2 in the solar spectrum and ＋0.09 W m-2 in the thermal spectrum on a global average. The magnitude of surface RF is larger than the TOA forcing, with global mean shortwave forcing of-1.76 W m-2 and longwave forcing of ＋0.31 W m-2 . As a result, dust aerosol causes the absorption of 1.1 W m-2 in the atmosphere. The RF of dust aerosol is predicted to lead to a surface cooling of 0.5 K over the Sahara Desert and Arabian Peninsula. In the meantime, the upper troposphere is predicted to become warmer because of the absorption by dust. These changes in temperature lead to a more stable atmosphere, which results in increases in surface humidity. The upward sensible and latent heat fluxes at the surface are reduced, largely balancing the surface energy loss caused by the backscattering and absorption of dust aerosol. Precipitation is predicted to decrease moderately on a global scale.

关键词： dust aerosol radiative forcing direct radiative effect general circulation model

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基于劳资博弈模型的实用查询定价新算法

计算机研究与发展 2024年第12期61卷 3154-3167页

作者：王会举黄玮煊岳晓中南财经政法大学信息工程学院武汉430073

在数据要素化的推动下,传统查询定价方法因其前提假设要求过高、灵活动态性支持有限、关键因素考虑不足等问题,面临落地难的巨大挑战.为解决以上问题,创新设计了基于劳资博弈模型的查询定价算法,该算法利用劳资博弈模型对数据交易中参... 详细信息

在数据要素化的推动下,传统查询定价方法因其前提假设要求过高、灵活动态性支持有限、关键因素考虑不足等问题,面临落地难的巨大挑战.为解决以上问题,创新设计了基于劳资博弈模型的查询定价算法,该算法利用劳资博弈模型对数据交易中参与方进行建模,将数据交易平台和数据买方分别视作工会和用人单位;数据交易平台(工会)负责各交易数据集价值(劳动者工资)公平透明计算,以尽可能促成交易为目标;数据买方根据各数据集估量价值、自身需求和自身预算,决定各数据集购买数量,藉此实现兼顾三方利益的交易数据集定价.实验表明,该算法相比于流行的斯塔克伯格博弈模型,更能兼顾各方利益,更加公平;相比于传统的基于查询的数据定价方法,该定价算法更易落地应用、更具动态灵活性,可以跟随查询结果的变化实现价格的动态调整.该定价算法时间复杂度为O(N)(N为查询相关数据集个数),且具有无套利性.

关键词：查询定价劳资博弈模型数据定价数据交易公平定价

公安院校公文写作教学改革的探索实践与再思考

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铁道警察学院学报 2024年第2期34卷 123-128页

作者：王慧菊郑州警察学院公安基础教研部河南郑州450053

公文写作能力是当代公安民警的必备能力。调研发现,当前新入职民警在写作方面普遍存在公文格式规范意识弱、文章内容层次杂乱无章、表达流畅度简练度较低、写作重心把握不准等问题。公安院校公文写作教学也存在“学练不协调”“学用不... 详细信息

公文写作能力是当代公安民警的必备能力。调研发现,当前新入职民警在写作方面普遍存在公文格式规范意识弱、文章内容层次杂乱无章、表达流畅度简练度较低、写作重心把握不准等问题。公安院校公文写作教学也存在“学练不协调”“学用不一致”“课时少内容多”等矛盾痛点。为解决上述问题,公安院校亟须结合一线实际需求,推进公文写作教学改革。教学观念上,融会贯通,建立“生活处处皆公文写作”的大写作观;教学目标上,锚定写作思维,锻炼写作基础能力;教学过程中,做实实训,精心设计实训项目。以一线岗位诉求为方向,以满足基层新入职民警的写作能力素养为首要任务、基础任务,以奠定未来发展所需的写作核心素养为中心任务,明确课程目标,重构教学内容,推进公安院校公文写作教学改革更加深入彻底。

关键词：公安院校教学改革实战需求写作基础能力

度量测度空间中障碍问题解的Caccioppoli型不等式

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西安工业大学学报 2019年第6期39卷 629-631页

作者：王会菊西北工业大学理学院

为了研究在度量情形下Orlicz-Sobolev空间中的障碍问题,本文通过选取适当的截断函数,利用“填洞法”证明了障碍问题解的Caccioppoli型不等式。文中结论为研究障碍问题解的有界性的提供了理论基础。

关键词：度量测度空间障碍问题 Caccioppoli型不等式有界性

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《阿Q正传》艺术谱系析解

河北科技师范学院学报（社会科学版） 2008年第4期7卷 14-16,20页

作者：王慧菊铁道警官高等专科学校警察管理系河南郑州450053

《阿Q正传》的艺术谱系可从叙事与形象两方面采用作品细读的方法来查考。《阿Q正传》的叙事手法与中国小说的史传式叙事手法恰相反对,而与《红楼梦》紧密相承;阿Q的精神气质是《庄子》"圣人"形象经历史积淀后的粗卑化呈现。

关键词：《阿Q正传》艺术谱系《红楼梦》《庄子》

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公安院校职前写作课程建设之我见

河南教育学院学报（哲学社会科学版） 2013年第2期32卷 130-132页

作者：王慧菊铁道警官高等专科学校公共基础部

针对当前警察招录体制改革和公安院校体制改革的现状与问题,把公务员招录考试与公安院校教学实际相结合,建设职前写作课程,是提升公安院校人才培养质量,提高学生就业能力的重要举措。

关键词：公务员招录考试教学改革应用写作公安院校职前写作课程

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芳香族化合物对木质素降解酶系分泌的影响

中国皮革 2016年第3期45卷 41-45,50页

作者：刘瑞李彦春赵艳霞王惠举王智齐鲁工业大学皮革化学与工程学院山东济南250353

以黄孢原毛平革菌为试验菌种,研究了6种染料和5种酚对黄孢原毛平革菌分泌木质素降解酶系的影响。结果表明:染料对木质素过氧化物酶的诱导作用具有阶段性,且染料分子中引入磺酸基会降低染料对木质素降解酶分泌的抑制。对于酚来说,苯环上... 详细信息

以黄孢原毛平革菌为试验菌种,研究了6种染料和5种酚对黄孢原毛平革菌分泌木质素降解酶系的影响。结果表明:染料对木质素过氧化物酶的诱导作用具有阶段性,且染料分子中引入磺酸基会降低染料对木质素降解酶分泌的抑制。对于酚来说,苯环上酚羟基处于间位比处于邻位对锰过氧化物酶的分泌抑制作用小,且羟基数量越多,对木质素过氧化物酶的分泌抑制作用越小。

关键词：染料酚木质素过氧化物酶锰过氧化物酶黄孢原毛平革菌