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基于冶金行业铁前MES系统数据库治理优化 被引量:1
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作者 郭凌宙 《福建冶金》 2022年第4期55-59,共5页
本文针对钢铁企业铁前MES海量级数据库系统SQL查询效率低的问题,通过索引创建、等价改写、业务逻辑优化方法手段,使得数据库性能显著地提升,用户体验感增强。由数据库服务器性能指标(CPU占用率、逻辑读、响应时间)分析计算可知,铁前MES... 本文针对钢铁企业铁前MES海量级数据库系统SQL查询效率低的问题,通过索引创建、等价改写、业务逻辑优化方法手段,使得数据库性能显著地提升,用户体验感增强。由数据库服务器性能指标(CPU占用率、逻辑读、响应时间)分析计算可知,铁前MES数据库整体性能提升了4倍。 展开更多
关键词 海量级 优化 执行计划 数据库治理 索引
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PostgreSQL在GeoEast多学科数据管理系统中的应用 被引量:6
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作者 师伟 林茂春 +2 位作者 王向辉 李军茹 程实 《电子技术与软件工程》 2021年第10期205-208,共4页
本文介绍了一款开源企业级数据库PostgreSQL(PG),探讨了PG与ORACLE数据库的在地震勘探行业的优劣势,并提出一种具有商业价值的,采用企业级SQL标准封装多学科数据业务对象的方案,并对应用接口性能基于盆地级勘探数据规模下进行测试和分析。
关键词 POSTGRESQL PB海量数据 企业数据管理 性能
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Currents and mixing in the northern South China Sea 被引量:3
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作者 刘军亮 蔡树群 王盛安 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2010年第5期974-980,共7页
We investigated the vertical distribution of current velocity data of the entire water column at a site on the continental shelf of the northern South China Sea(SCS) from August 4 to September 6,2007,and found that th... We investigated the vertical distribution of current velocity data of the entire water column at a site on the continental shelf of the northern South China Sea(SCS) from August 4 to September 6,2007,and found that the characteristics of barotropic and baroclinic tides are mainly diurnal.During the observation period,we also estimated the mixing before and after the passage of Typhoon Pabuk.We found that the internal-wave-scale dissipation rate,the turbulent dissipation rate,and the mixing rate in every water layer increased by about an order of magnitude after the typhoon passage.We analyzed a case of abrupt strong current and calculated the mixing rate before,during,and after the typhoon event.The results show that the internal-wave-scale dissipation rate and the mixing rate in every water layer increased by about two orders of magnitude during the event,while the turbulent dissipation rate increased by about an order of magnitude.Passage of the abrupt strong current could also have increased the mixing rate of affected seawater by more than an order of magnitude.However,the passage of the typhoon differed in that there was an increase in mixing only in the lower layer where the abrupt strong current was particularly strong.The variation of the mixing rate may help us to understand the effects of typhoons and abrupt strong currents on the mixing of seawater. 展开更多
关键词 current field TYPHOON abrupt strong current mixing rate South China Sea (SCS)
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Estimates of Autumntime Benthic Secondary Production in Laizhou Bay and Adjacent Bohai Sea Waters
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作者 HUA Er ZHOU Hong ZHANG Zhinan YU Zishan 《Journal of Ocean University of China》 SCIE CAS 2010年第3期279-285,共7页
The whole metazoan community inhabiting Laizhou Bay and adjacent Bohai Sea waters were sampled in late autumn, 2006. Secondary production estimates for macrofauna and meiofauna were made separately. Total benthic seco... The whole metazoan community inhabiting Laizhou Bay and adjacent Bohai Sea waters were sampled in late autumn, 2006. Secondary production estimates for macrofauna and meiofauna were made separately. Total benthic secondary production was as high as 8.38 ±4.08 g ash-free dry weight (AFDW) m^-2 a^-1, which represented the autumn production level. In general, macrofaunal secondary production in Laizhou Bay was much lower than that in adjacent Bohai Sea areas. In contrast, meiofaunal secondary production in Laizhou Bay was higher than that in adjacent Bohai Sea areas. Macrofatma contributed 61% to benthic secondary production (5.09 ±3.26 g AFDW m^-2 a^-1), lower than the value in previous studies in Bohai Sea. Sediment granulometric characteristics and bottom-water salinity could explain the substantial variability in the macrofauna biomass and production. Meiofaunal production was an important component of benthic production and exceeded macrofauna production under exceptional conditions, e.g. in Laizhou Bay, where macrofauna was restricted. Chlorophyll pigments (Chl-a) concentrations in sediment explained the general meiofaunal biomass and production distribution here. 展开更多
关键词 benthic secondary production MEIOFAUNA MACROFAUNA Laizhou Bay the Bohai Sea
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