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Research on Algorithm for Mining Negative Association Rules Based on Frequent Pattern Tree

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Wuhan University Journal of Natural Sciences 2006年第1期11卷 37-41页

作者： ZHU Yu-quan YANG He-biao SONG Yu-qing XIE Cong-hua School of Computer Science and Communication Engineering Jiangsu University Zhenjiang 212013 JiangsuChina

Typical association rules consider only items enumerated in transactions. Such rules are referred to as positive association rules. Negative association rules also consider the same items, but in addition consider negated items （i. e. absent from transactions）. Negative association rules are useful in market-basket analysis to identify products that conflict with each other or products that complement each other. They are also very convenient for associative classifiers, classifiers that build their classification model based on association rules. Indeed, mining for such rules necessitates the examination of an exponentially large search space. Despite their usefulness, very few algorithms to mine them have been proposed to date. In this paper, an algorithm based on FP tree is presented to discover negative association rules.

关键词： data mining FP-tree Negative Association Rules

Influences of Ho Doping on Structure,Ferroelectric,Energy Storage and Optical Properties of KNN-SYbN Transparent Ceramics

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Journal of Wuhan University of Technology(Materials Science) 2022年第4期37卷 587-590页

作者：孙亚兵 WANG Jiangting LIU Haonan 王华 XU Jiwen School of Materials Science and Engineering Guilin University of Electronic TechnologyGuilin 541004China Guangxi Key Laboratory of Information Materials Guilin University of Electronic TechnologyGuilin 541004China

Ho doping 0.825K_(0.5)Na_(0.5)NbO_(3)-0.175Sr(Yb_(0.5)Nb_(0.5))_(O3)(KNN-SYbN-x%Ho)transparent ceramics were prepared by solid-state sintering *** structure,ferroelectric,energy storage,and optical properties of KNN-SYbN-x%Ho were *** the addition of Ho,under the excitation of a 980 nm laser,the ceramics exhibit up-conversion luminescence properties with wavelengths of 550 nm and 670 nm,however,the ceramics change from pseudo-cubic phase to triphase-orthorhombic phase and the light transmittance *** addition of Ho significantly enhances the ferroelectric properties and the energy storage performance of KNN-SYbN-x%Ho *** x=0.15,the residual polarization P_(r)=9.11μC/cm^(2),while x=0.20,the maximum energy storage density W_(rec) reaches 0.26 J/cm^(3),and the energy storage efficiencyηreaches 87.1%.

关键词： Ho doping transmittance ceramics up-conversion luminescence ferroelectric properties energy storage

Using multi-satellite microwave remote sensing observations for retrieval of daily surface soil moisture across China

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Water Science and Engineering 2019年第2期12卷 85-97页

作者： Ke Zhang Li-jun Chao qing-qing Wang Ying-chun huang Rong-hua Liu Yang Hong Yong Tu Wei Qu Jin-yin Ye State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering Hohai UniversityNanjing 210098China College of Hydrology and Water Resources Hohai UniversityNanjing 210098China China Institute of Water Resources and Hydropower Research Beijing 100038China Research Center on Flood&Drought Disaster Reduction of the Ministry of Water Resources Beijing 100038China School of Civil Engineering Tsinghua UniversityBeijing 100084China Anhui Branch of China Meteorological Administration Training Centre Hefei 230031China

The objective of this study was to retrieve daily composite soil moisture by jointly using brightness temperature observations from multiple operating satellites for near real-time application with better coverage and higher *** approach was to first apply the single-channel brightness radiometric algorithm to estimate soil moisture from the respective brightness temperature observations of the SMAP,SMOS,AMSR2,FY3B,and FY3C satellites on the same day and then produce a daily composite dataset by averaging the individual satellite-retrieved soil *** further evaluated our product,the official soil moisture products of the five satellites,and the ensemble mean (i.e.,arithmetic mean) of the five official satellite soil moisture products against ground observations from two networks in Central Tibet and Anhui Province,*** results show that our product outperforms the individual released products of the five satellites and their ensemble means in the two validation *** root mean square error (RMSE ) values of our product were 0.06 and 0.09 m3/m3 in Central Tibet and Anhui Province,*** to the ensemble mean of the five satellite products,our product improves the accuracy by 9.1% and 57.7% in Central Tibet and Anhui Province,*** demonstrates that jointly using brightness temperature observations from multiple satellites to retrieve soil moisture not only improves the spatial coverage of daily observations but also produces better daily composite products.

关键词： Soil moisture retrieval Passive microwave remote sensing Multiple satellites Surface hydrology SMAP SMOS AMSR2 FY3B FY3C

Phase and CCT Diagram of an N-Containing 8%Cr Roller Steel

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Journal of Harbin Institute of Technology(New Series) 2013年第6期20卷 112-117页

作者： Shu-hua sun Bo Wang Zhen-hua Wang Yang Gao Ming-Wei Guo Wan-Tang Fu State Key Laboratory of Metastable Materials Science and Technology Yanshan University College of Sciences Yanshan University Key Laboratory of Advanced Forging & Stamping Technology and Science (Yanshan University) Ministry of Education of China China First Heavy Industries

The pseudo-equilibrium phase diagram and continuous cooling transformation diagram of an N-containing 8% Cr roller steel were investigated by using thermodynamic calculation,differential scanning calorimetry, X-ray diffraction, expansion method, and so on. Under equilibrium conditions, the main carbonitrides are MX,M7C3,and M23C6types. The measured Ac1,Ac3,start temperature of martensitic transformation,and M7C3transformation temperatures are 811,855,324,and 1100 ℃,respectively. Bainite appears at cooling rates ranging from 0. 5 to 5 ℃ / s and ferrite forms at grain boundaries at a cooling rate lower than 0. 5 ℃ / s. Finally,the effects of adding N and lowering the C content on workability and mechanical properties of common 8%Cr steel were discussed.

关键词： high Cr roller steel phase diagram continuous cooling transformation N alloying

Photocatalysis:an overview of recent developments and technological advancements

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Science China Chemistry 2020年第2期63卷 149-181页

作者： Yuanxing Fang Yun Zheng Taofang Yong Chen Yaodong Zhu qing Liang hua Sheng Zhaosheng Li Chuncheng Chen Xinchen Wang State Key Laboratory of Photocatalysis on Energy and Environment College of ChemistryFuzhou UniversityFuzhou 350116China Key Laboratory of Molecular Designing and Green Conversions Fujian Province UniversityCollege of Materials Science and EngineeringHuaqiao UniversityXiamen 361021China Collaborative Innovation Center of Advanced Microstructures National Laboratory of Solid State MicrostructuresCollege of Engineering and Applied SciencesNanjing UniversityNanjing 210093China Key Laboratory of Photochemistry CAS Research/Education Center for Excellence in Molecular SciencesInstitute of ChemistryChinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China

Photocatalysis,which is the catalyzation of redox reactions via the use of energy obtained from light sources,is a topic that has garnered a lot of attention in recent years as a means of addressing the environmental and economic issues plaguing society *** particular interest are photosynthesis can potentially mimic a variety of vital reactions,many of which hold the key to develop sustainable energy *** light of this,many of the technological and procedural advancements that have recently occurred in the field are discussed in this review,namely those linked to:(1)photocatalysts made from metal oxides,nitride,and sulfides;(2)photocatalysis via polymeric carbon nitride(PCN);and(3)general advances and mechanistic insights related to TiO2-based *** challenges and opportunities that have arisen over the past few years are discussed in *** concepts and experimental procedures which could be useful for eventually overcoming the problems associated with photocatalysis are presented herein.

关键词： photocatalysis carbon nitride metal oxides metal nitride metal sulfide mechanism TiO2

Monitoring dispatch information system of trucks and shovels in an open pit based on GIS/GPS/GPRS

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Journal of China University of Mining and Technology 2008年第2期18卷 288-292页

作者： GU qing-hua LU Cai-wu LI Fa-ben WAN Chang-yong School of Management Xi ＇an University of Architecture ＆ Technology Xi＇an Shaanxi 710055 China Luoyang Luanchuan Molybdenum Industry Group Inc. Luoyang Henan 471500 China

Using GIS,GPS and GPRS,an intelligent monitoring and dispatch system of trucks and shovels in an open pit has been designed and *** system can monitor and dispatch open-pit trucks and shovels and play back their historical *** intelligent data algorithm is proposed in a practical *** algorithm can count the times of deliveries of trucks and load- ings of *** on real scenes show that the performance of this system is stable and can satisfy production standards in open pits.

关键词： GIS GPS GPRS 数据加工露天开采矿

1956年医学史高级师资进修班及其影响探究

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中华医史杂志 2022年第4期52卷 227-234页

作者：柴桦卿平四川大学华西临床医学院/华西医院成都610041

1956年医学史高级师资进修班是在新中国初期"学习苏联"进行教学改革、"团结中西医"、实行"双百方针"的历史背景下,由卫生部直接推动、卫生部中医研究院举办的第一次系统的医学史高级师资培训,进修班教学安排合理,师资阵容强大,取得了良... 详细信息

1956年医学史高级师资进修班是在新中国初期"学习苏联"进行教学改革、"团结中西医"、实行"双百方针"的历史背景下,由卫生部直接推动、卫生部中医研究院举办的第一次系统的医学史高级师资培训,进修班教学安排合理,师资阵容强大,取得了良好效果。尽管结业后只有少数学员长期专职从事医学史教学研究工作,但依然取得了突出的学术成就,促进了20世纪后半叶中国高等院校医学史的教学与研究,为今天开展医学史师资培训及教学研究带来了宝贵启示。

关键词：医学史师资培训医学教育

Assessment of prophylactic antibiotics administration for acute pancreatitis:a meta-analysis of randomized controlled trials

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Chinese Medical Journal 2020年第2期133卷 212-220页

作者： Nan Ding Yong-Hui sun Li-Mei Wen Jian-hua Wang Jian-hua Yang Kun Cheng Hai Lin Qi-Long Chen Department of Pharmacy The First Affiliated Hospital of Xinjiang Medical UniversityUrumqiXinjiang 830054China Digestion and Vascular Center Department of Pancreas SurgeryThe First Affiliated Hospital of Xinjiang Medical UniversityUrumqiXinjiang 830054China

Background:Recent evidence has shown that prophylactic antibiotic treatment in patients with acute pancreatitis is not associated with a significant decrease in mortality or *** use and efficacy of prophylactic antibiotic treatment in acute pancreatitis remain *** meta-analysis was conducted to assess whether antibiotic prophylaxis is beneficial in patients with acute ***:We searched randomized controlled trials(RCTs)of prophylactic use of antibiotics using Medline(PubMed),Embase,the Cochrane Library,and Web of *** data were analyzed using Review Manager 5.3 *** performed pooled analyses for infected pancreatic necrosis,mortality,surgical intervention,and non-pancreatic *** ratios(ORs)from each trial were pooled using a random or fixed effects model,depending on the heterogeneity of the included ***-group analysis or sensitivity analysis was conducted to explore potential sources of heterogeneity,when ***:Totally,11 RCTs involving 747 participants were included,with an intervention group(prophylactic use of antibiotics,n=376)and control group(n=371).No significant differences were found regarding antibiotic prophylaxis with respect to incidence of infected pancreatic necrosis(OR,0.74;95%confidence interval[CI],0.50–1.09;P=0.13),surgical intervention(OR,0.92;95%CI,0.62–1.38;P=0.70),and morality(OR,0.71;95%CI,0.44–1.15;P=0.16).However,antibiotic prophylaxis was associated with a statistically significant reduction in the incidence of non-pancreatic infection(OR,0.59;95%CI,0.42–0.84;P=0.004).Conclusions:Prophylactic antibiotics can reduce the incidence of non-pancreatic infection in patients with AP.

关键词： Acute pancreatitis Prophylactic administration Antibiotics Meta-analysis

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风电直流外送系统受端换流站过电压抑制策略

电力电子技术 2023年第10期57卷 48-50,64页

作者：李婧王卿玮孙庆超谢莹华深圳供电局有限公司广东深圳510000

风电经直流外送系统受端故障必然在系统内产生盈余功率,由其导致的换流器过电压难题须被攻克。首先分析了换流器的过电压机理;其次,在受端换流站中设计了晶闸管旁路支路,保证在换流站承受过电压前将其旁路;再次,对送端换流站设计了耗能... 详细信息

风电经直流外送系统受端故障必然在系统内产生盈余功率,由其导致的换流器过电压难题须被攻克。首先分析了换流器的过电压机理;其次,在受端换流站中设计了晶闸管旁路支路,保证在换流站承受过电压前将其旁路;再次,对送端换流站设计了耗能子模块拓扑结构,防止风电盈余功率致使送端换流站产生过电压;最后构建了数字物理混合实验平台,数字侧包括25台风电机组,物理侧为双端柔性直流输电系统实验样机,采用混合实验的方式对风电直流外送系统受端交流故障抑制策略的工程适用性进行了验证。

关键词：换流器故障盈余功率过电压