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MiNT-OLAP cluster： minimizing network transmission cost in OLAP cluster for main memory analytical database

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Frontiers of Computer Science 2012年第6期6卷 668-676页

作者： Min JIAO Yansong ZHANG zhanwei wang Shan wang DEKE Lab Renmin University of ChinaBeijing 100872China National Survey Research Center Renmin University of ChinaBeijing 100872China School of Information Renmin University of ChinaBeijing 100872China

Powerful storage, high performance and scalability are the most important issues for analytical databases. These three factors interact with each other, for example, powerful storage needs less scalability but higher performance, high performance means less consumption of indexes and other materializations for storage and fewer processing nodes, larger scale relieves stress on powerful storage and the high performance processing engine. Some analytical databases （ParAccel, Teradata） bind their performance with advanced hardware supports, some （Asterdata, Greenplum） rely on the high scalability framework of MapReduce, some （MonetDB, Sybase IQ, Vertica） highlight performance on processing engine and storage engine. All these approaches can be integrated into an storage-performance-scalability （S- P-S） model, and future large scale analytical processing can be built on moderate clusters to minimize expensive hardware dependency. The most important thing is a simple software framework is fundamental to maintain pace with the development of hardware technologies. In this paper, we propose a schemaaware on-line analytical processing （OLAP） model with deep optimization from native features of the star or snowflake schema. The OLAP model divides the whole process into several stages, each stage pipes its output to the next stage, we minimize the size of output data in each stage, whether in central processing or clustered processing. We extend this mechanism to cluster processing using two major techniques, one is using NetMemory as a broadcasting protocol based dimension mirror synchronizing buffer, the other is predicatevector based DDTA-OLAP cluster model which can minimize the data dependency of star-join using bitmap vectors. Our OLAP model aims to minimize network transmission cost （MINT in short） for OLAP clusters and support a scalable but simple distributed storage model for large scale clustering processing. Finally, the experimental results show the speedup and s

关键词： OLAP cluster MINT NetMemory schemaaware OLAP

Thermal-Hydraulic Characteristics of Twisted Elliptical Tube Bundle in Staggered Arrangement

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Journal of Thermal Science 2021年第6期30卷 1925-1937页

作者： LI Xiuzhen wang Lin FENG Rong wang zhanwei ZHU Dongsheng Institute of Building Energy and Thermal Science Henan University of Science and TechnologyLuoyang 471023China CAS Key Laboratory of Renewable Energy Guangzhou 510640China School of Mechanical Engineering Shaanxi Key Laboratory of Industrial AutomationShaanxi University of TechnologyHanzhong 723001China

Based on experimental data,numerical simulations by turbulent air flowing across staggered tube bundle composed of twisted elliptical tube(TET)with constant tube wall temperature are conducted in present *** study on the thermal-hydraulic characteristics of air crossflow in TET bundles is investigated with physical parameters and Reynolds number(Re).The results show that spiral channels created by spiral deformation of TETs have a diversion effect on the air flow,which changes the flow direction of the air near the tube *** air in the near wall region is a three-dimensional flow,consisting of a flow perpendicular to the normal direction of the elliptical cross section and a spiral flow along the helicoid on the downstream side and the upstream *** the interaction of the spiral channels makes the two flows and their mixing more *** excellent heat transfer performance of staggered TET bundles is confirmed by the comparison of the comprehensive heat transfer performance with that of circular tube *** average Nusselt number(Nu)increases with the increase of the aspect ratio(A/B)and with the increase of Re while decreases as the twist pitch(S)*** average Euler number(Eu)increases as A/B increases,while it decreases as Re increases and as S *** to the fact that the suitable correlations for staggered TET bundles are not reported,correlations for Nu and Eu obtained from experimental data and numerical results are presented in the multiple forms.

关键词： twisted elliptical tube heat transfer enhancement pressure drop performance cross flow

Energy and Exergy Analysis of a Cooling/Power Cogeneration Ejector Refrigeration System

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Journal of Thermal Science 2022年第2期31卷 448-462页

作者： YANG Mengke LI Xiuzhen wang Lin YUAN Junfei wang zhanwei LIANG Kunfeng Institute of Refrigeration and Air conditioning Henan University of Science and TechnologyLuoyang 471023China

The organic Rankine cycle is introduced into the conventional ejector refrigeration(CER)system to establish the low-grade heat-driven cooling/power cogeneration ejector refrigeration(CPC-ER)system using the isobutane as the *** comparison with the CER system where external power is consumed by the circulating pump,the power output from the CPC-ER system is more than the power consumption of its circulating pump so that a portion of net power is derived from the CPC-ER *** on the mathematical model of thermodynamics,energy and exergy analysis of the CPC-ER system is carried out and compared with the CER *** results reveal that the equivalent coefficient of performance(COP)of the CPC-ER system is 41.14%to 71.30%higher than that of the CER system,and the exergy efficiency of the CPC-ER system is 1.32 to 1.49 times higher than that of the CER *** the power produced by the turbine and the total exergy output from the CPC-ER system approach the maximum,as the generating temperature in the generator is up to 80°*** CPC-ER system has the higher energy utilization efficiency than the CER system,and it is suitable for the cooling and power-required places with low-grade thermal sources.

关键词： ejector refrigeration exergy power consumption equivalent COP

Insights on evolution of virulence and resistance from the whole-genome analysis of a predominant methicillin-resistant Staphylococcus aureus clone sequence type 239 in China

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Chinese Science Bulletin 2014年第11期59卷 1104-1112页

作者： Hongbin Chen Xi Yang Qi wang Chunjiang Zhao Henan Li Wenqiang He Xiaojuan wang Feifei Zhang zhanwei wang Minjun Chen Baoli Zhu Hui wang Department of Clinical Laboratory Peking University People’s Hospital Key Laboratory of Pathogenic Microbiology & Immunology Institute of MicrobiologyChinese Academy of Sciences Department of Clinical Laboratory Peking Union Medical College Hospital

Earlier, we reported that ST239 was the15-year predominant methicillin-resistant Staphylococcus aureus(MRSA) clone in China. In this study, MRSA strain CN79 belonging to ST239 and isolated from blood was used to determine the whole genome sequence. Comparative genomics analysis was done between MRSA CN79and 25 sequenced S. aureus in the NCBI GenBank database. A total of 2,734 protein-encoding genes were identified in the MRSA CN79 genome, which carries 11antibiotic resistance genes and 65 virulence genes. Two prophages phiCN79A and phiNM3-like were found on the MRSA CN79 genome. MRSA CN79 carries 30 specific genes that are absent from the 25 sequenced S. aureus genomes. Most of them were prophage-related *** antibiotic resistance genes, such as b-lactamase and ABC-type multidrug transport system gene, were located on the genomic island mSab. The antibiotic resistance genes, such as tet(M), ermA1, and blaZ, were also located on different transposons. The virulence genes sea,map, hlb, and sak are located on phiNM3-like prophage and the exotoxin genes are carried on the genomic island mSaa. These results suggest that ST239 MRSA strains are widespread owing to horizontal acquisition of the mobile genetic elements harbored antibiotic resistance genes and virulence genes in response to environmental selective pressures, such as antibiotics and the human immune system during evolution.

关键词：金黄色葡萄球菌基因组分析毒力基因进化过程序列类型中国克隆 GenBank

Present Situation and Prospect of Comprehensive Planting and Culture in Paddy Fields in Northeast China

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Asian Agricultural Research 2022年第2期14卷 54-56,65页

作者： Xiaoguang ZU Ming CHEN Tiegang LIU Lihe FAN zhanwei wang Xiujie ZU Changchun Agricultural Technology Extension Station Changchun 130033 China Dehui Aquatic Technology Extension Center Dehui 130300 China Jilin Academy of Fisheries Sciences Changchun 130033 China

The rice planting area in Northeast China has reached 5.6 million ha,but the utilization rate of comprehensive culture area in paddy field is only 2%.It is mainly dominated by fish culture in paddy field and crab culture in paddy field,which has broad development *** recent years,the comprehensive planting and culture area of paddy fields in Liaoning Province has developed rapidly with a total of 80000 *** accordance with the local environmental conditions,Heilongjiang and Jilin regions have introduced a new model and technology of comprehensive planting and culture in paddy fields,and developed a comprehensive planting and breeding model of paddy fields with *** present,the comprehensive planting and culture in paddy fields in Northeast China is still in the stage of rapid development,which needs to be further developed towards specialization,scale,industrialization,high quality and brand.

关键词： Northeast region Comprehensive planting and culture in paddy field Model

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一类分数阶复杂网络系统的有限时间同步控制

深圳大学学报（理工版） 2016年第1期33卷 96-101页

作者：毛北行王战伟郑州航空工业管理学院数理系河南郑州450015

研究一类分数阶复杂网络系统的有限时间混沌同步问题,基于Lyapunov稳定性理论和分数阶微积分的相关理论,给出控制律的设计,得到了系统取得有限时间同步的充分条件,估算了系统取得同步所需的时间.研究结果表明,一定条件下分数阶复杂网络... 详细信息

研究一类分数阶复杂网络系统的有限时间混沌同步问题,基于Lyapunov稳定性理论和分数阶微积分的相关理论,给出控制律的设计,得到了系统取得有限时间同步的充分条件,估算了系统取得同步所需的时间.研究结果表明,一定条件下分数阶复杂网络混沌系统是有限时间同步的,仿真结果验证了方法的可行性.

关键词：分数阶系统有限时间混沌同步复杂网络误差系统控制

Construction of Water-saving Ecological Aquaculture Model in Ponds in North China

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Asian Agricultural Research 2022年第10期14卷 18-22页

作者： Lihua CHEN Yanhui LIU Tiegang LIU Bingkun YANG Xiuying LI zhanwei wang Xiujie ZU Baicheng Yueliangpao Reservoir Administration Da'an 131307China Jilin Academy of Fisheries Sciences Changchun 130033China

[Objectives]To explore the ecological aquaculture model in ponds in North China,several single techniques were assembled into the same culture system.[Methods]Three ponds were selected,the species and stocking rate were exactly the same,the water was not changed during the culture period,and the water loss due to evaporation and leakage was *** the middle of May,the hydrochemical indicators such as ammonia nitrogen,nitrite nitrogen,water temperature,dissolved oxygen and pH were monitored every 10 *** to the monitoring results of ammonia nitrogen,carbon sources were added to the culture ponds to adjust the ratio of C to N,and carbon sources were added 9 times during the culture *** stocking rate and yield per unit area were accurately measured at the beginning and end of the experiment,and no less than 30 fishes were randomly sampled to calculate the relevant growth indicators and feed coefficients.[Results]Except that the nonionic ammonia in pond 3#exceeded the standard by 10.3%on July 25,all other hydrochemical indicators met the Fisheries Water Quality Standard,and there was no significant difference in all hydrochemical indicators at the same time(P>0.05).The survival rate in 3 ponds was more than 95.0%,the average body weight of individuals out of the pond had no difference(P>0.05),and the feed coefficient was *** was no disease during the culture period,and the water was saved by 46.6%compared with the traditional culture model.[Conclusions]This study can provide a basis for the construction of a new model suitable for ecological aquaculture in ponds in North China.

关键词： Ponds in North China Water Saving Ecology Model Construction

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相变储能冷却系统中储液器的设计与实验研究

过程工程学报 2020年第12期20卷 1439-1447页

作者：袁俊飞王林王占伟焦永刚河南科技大学制冷热泵空调技术研究所河南洛阳471023 石家庄铁道大学四方学院机械工程学院河北石家庄050043

相变储能冷却系统是用于短时大功率电子设备热管理的重要技术,系统在工作过程中的温度压力控制是该系统在应用过程中急需解决的问题。以NH3为制冷工质,针对10 kW热源的储能冷却系统中储液器进行理论分析和设计计算,建立相应的实验台,测... 详细信息

相变储能冷却系统是用于短时大功率电子设备热管理的重要技术,系统在工作过程中的温度压力控制是该系统在应用过程中急需解决的问题。以NH3为制冷工质,针对10 kW热源的储能冷却系统中储液器进行理论分析和设计计算,建立相应的实验台,测试其运行特性。结果表明,储液器作为该系统的定压设备,在动力设备和热源启动及运行过程中,对系统循环工质起到补充和存储作用。储液器的压力波动随热源功率的增加而增大,随储液器和管路容积比的增大而减小。当储液器和管路系统的容积比为1.48时,热源运行期间温度波动仅为1.2℃。在热源受到扰动时,储液器和储能器的耦合工作特性能有效抑制系统的温度压力波动。

关键词：冷却系统储液器相变稳定性

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基于融合的贝叶斯网络的冷水机组故障诊断

化工学报 2018年第7期69卷 3167-3173页

作者：王占伟王林梁坤峰袁俊飞王智伟河南科技大学制冷热泵空调技术研究所河南洛阳471023 西安建筑科技大学环境学院陕西西安710055

基于贝叶斯网络(BN)的开放式结构,将现场观测信息融入到BN中,用以改善故障诊断性能。引入距离拒绝机制,以确定在故障为假时传感器测量参数的概率分布。提出了一种基于融合的BN的冷水机组故障诊断方法,该方法能够检测新故障和动态更新故... 详细信息

基于贝叶斯网络(BN)的开放式结构,将现场观测信息融入到BN中,用以改善故障诊断性能。引入距离拒绝机制,以确定在故障为假时传感器测量参数的概率分布。提出了一种基于融合的BN的冷水机组故障诊断方法,该方法能够检测新故障和动态更新故障库。使用ASHRAE RP-1043的故障实验数据对提出的方法进行验证,结果显示:提出方法对新故障NF1的检测正确率为99.8%,现场观测信息的融入将新故障NF2的检测正确率提高了32.6%,并将已知故障rl(制冷剂泄露)和ro(制冷剂充注过量)的诊断正确率分别提高了4.8%和11.2%。

关键词：冷水机组故障诊断算法控制集成