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HYDRAULIC CHARACTERISTICS OF PLUG ENERGY DISSIPATER IN FLOOD DISCHARGE TUNNEL

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Journal of Hydrodynamics 2009年第6期21卷 799-806页

作者： TIAN Zhong XU wei-lin WANG wei LIU Shan-Jun State Key Laboratory of Hydraulics and Mountain River Engineering Sichuan University Chengdu 610065 China

The hydraulic characteristics of three types of plugs, namely, the single plug, the stepped plug and the gradually contracted plug were studied by means of experimental and numerical simulations. Main research findings are as follows. For the single plug, the pressure recovery lengths inside and after the plug range from 0.63-1.05 times and 2.02-2.84 times of the tunnel diameter, respectively. For the stepped plug, the lengths are 0.24-0.32 times and 1.62-2.84 times of the tunnel diameter, respectively. The best ratio of the inlet diameter to the outlet diameter of the gradually contracted plug can be expressed by a linear function. The relationship between the head loss coefficient and the area contraction ratio is obtained. The incipient cavitation numbers of different plugs are experimentally and numerically determined, and the incipient cavitation numbers are expressed by a formula. Model experiment with scale of 1：50 was carried out on a pressure tunnel with three-stage gradually contracted plugs. The results show that this type of energy dissipater is suitable for spill tunnels of high head （nearly 200 m） and large flow rate （nearly 2500 m^3/s）.

关键词： plug incipient cavitation number energy dissipater CFD

SCALE EFFECT OF I MPINGING PRESSURE CAUSED BY SUBMERGED JET

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Journal of Hydrodynamics 2005年第4期17卷 478-482页

作者： TIAN Zhong XU wei-lin WANG wei LIU Shan-jun DONG Jian-wei State Key Hydraulics Laboratory of High Speed Flows Sichuan University Chengdu 610065 China Military Oil Supply Engineering Department Logistical Engineering University Chongqing 400016China

The characteristics of the impinging pressure at the jet equipment where the maximum jet velocity can reach 50m/s were studied. By comparing the impinging pressure with the one measured at the low velocity conditions, two conclusions of the scale effect are drawn： firstly, the velocity attenuation degree is smaller than that of low velocity jet, and secondly, the relative impinging width is narrower than that of low-velocity jet. The reasons of the scale effect of the impinging pressure were elucidated through numerical simulation.

关键词： scale effect impinging pressure high-velocity jet numerical simulation

Monkeypox presenting as a chancre-like rash:A case report

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World Journal of Clinical Cases 2023年第25期11卷 6025-6030页

作者： wei-Fang Zhu Shu-Juan Song lin-wei wei Jian-Jun Qiao Division of Dermatology First Affiliated HospitalZhejiang University School of MedicineHangzhou 310003Zhejiang ProvinceChina Hangzhou Center of Disease Control and Prevention Hangzhou Center of Disease Control and PreventionHangzhou 310000Zhejiang ProvinceChina

BACKGROUND Since May 2022,outbreaks of monkeypox have occurred in many countries around the world,and several cases have been reported in *** SUMMARY A 38-year-old man presented with a small,painless,shallow ulcer on the coronary groove for 8 *** day after the rash appeared,the patient developed inguinal lymphadenopathy with *** patient had a history of male-male sexual activity and denied a recent history of travel *** virus was detected by quantitative polymerase chain reaction from the rash site and throat *** on the epidemiological history,clinical manifestations and nucleic acid test results,the patient was diagnosed with *** Monkeypox is an emerging infectious disease in *** presenting as a chancre-like rash is easily *** can be made based on exposure history,clinical manifestations and nucleic acid test results.

关键词： Monkeypox Chancre-Like rash China Case report

HYDRODYNAMIC UPLIFT FORCE AND STABILITY OF ARCIFORM PLUNGE POOL

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Journal of Hydrodynamics 2002年第3期14卷 8-12页

作者： Xu, wei-lin Wang, wei Liu, Shan-Jun Qu, Jing-Xue Diao, Ming-Jun Hydraulics Lab. of High Speed Flows Sichuan Univ. Chengdu 610065 China

Compared with general trapeziform plunge pools, an arciform plunge pool has its advantages, e.g. less excavate quantity, higher stability, etc. In this paper, the hydrodynamic pressure distribution on the soleplate of the arciform plunge pool is measured under a relatively dangerous condition of operation. The result is helpful to the design of the arciform plunge pool. The result also shows that the difference between the maximum and the minimum pressures on the upward surface of the soleplate may cause an additional uplift force on the soleplate under certain condition and should be taken into consideration in the uplift force calculation of the soleplate. The scour experiment verifies the higher stability of the arciform plunge pool.

关键词： Energy dissipators Hydrodynamics Pressure distribution Pressure measurement Stability Uplift pressure

Optimal management of nitrogen fertilizer in the main rice crop and its carrying-over effect on ratoon rice under mechanized cultivation in Southeast China

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Journal of Integrative Agriculture 2022年第2期21卷 351-364页

作者： HUANG Jin-wen WU Jia-yi CHEN Hong-fei ZHANG Zhi-xing FANG Chang-xun SHAO Cai-hong lin wei-wei WENG Pei-ying Muhammad Umar KHAN lin Wen-xiong Key Laboratory for Genetics Breeding and Multiple Utilization of Crops Ministry of Education/College of AgricultureFujian Agriculture and Forestry UniversityFuzhou 350002P.R.China Key Laboratory of Crop Ecology and Molecular Physiology(Fujian Agriculture and Forestry University) Fujian Province UniversityFuzhou 350002P.R.China Institute of Soil Fertilizer and Resources Environment Jiangxi Academy of Agricultural SciencesNanchang 330200P.R.China

This study attempted to clarify the carrying-over effect of different nitrogen treatments applied to the main crop on the crop population growth and yield formation of ratoon rice under mechanized cultivation in Southeast *** on the constant total nitrogen application amounts(225.00 kg ha;)in the main crop,an experiment with different ratios of basal and topdressing nitrogen fertilizer(the ratio of basal fertilizer:primary tillering fertilizer:secondary tillering fertilizer:booting fertilizer at 3:1:2:4(N1),3:2:1:4(N2),3:3:0:4(N3),and 4:3:0:3(N4),respectively,and a control without nitrogen treatment(N0))was set up across two consecutive years in field using hybrid rice variety Yongyou 1540 as the test *** results showed that the total tiller number and effective tillering percentage increased in the main crop under the N1 treatment,more nitrogen fertilizer applied in late growth stage of the main crop,and its effective tillering percentage of the main crop was the highest at up to 70.18%,which was 9.15%higher than that of conventional fertilization treatment(N4),more nitrogen fertilizer applied in early growth stage of the main *** same tendency was observed in leaf area index(LAI)value of the main crop and its subsequent ratoon rice,which were 16.52 and 29.87%higher,respectively,in the N1 treatment than that in the N4 treatment at the full heading *** same was true in the case of the transport rates of stem and sheath dry mater and the canopy light interception rates in both the main and its ratoon *** transport rate of stem and sheath in main crop rice under N1 treatment increased by 50.57%compared with N4 *** canopy light interception rate of N1 treatment increased by 5.07%compared with N4 treatment at the full heading stage of the ratoon ***,the total actual yield was the highest in the main and its ratoon crops under N1 treatment,averaging 17351.23 kg ha;in two-year trials,which was 23.00%higher than that

关键词： main crop ratoon rice nitrogen management crop stand low stubble height grain yield

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一种改进的Hadoop数据放置策略

华南理工大学学报（自然科学版） 2012年第1期40卷 152-158页

作者：林伟伟华南理工大学计算机科学与工程学院广东广州510006

采用现有的Hadoop默认数据放置策略时,若本地数据副本失效,从远程结点上恢复数据需要耗费大量数据传输时间,且随机选取数据放置结点可能会影响数据放置的负载均衡.为此,文中提出一种改进的数据放置策略.该策略基于结点网络距离与数据负... 详细信息

采用现有的Hadoop默认数据放置策略时,若本地数据副本失效,从远程结点上恢复数据需要耗费大量数据传输时间,且随机选取数据放置结点可能会影响数据放置的负载均衡.为此,文中提出一种改进的数据放置策略.该策略基于结点网络距离与数据负载计算每个结点的调度评价值,据此选择一个最佳的远程数据副本的放置结点,从而既能实现数据放置的负载均衡,又能实现良好的数据传输性能.在Hadoop平台上实现了所提出的数据副本放置改进策略,结果表明,与系统默认策略相比,文中提出的策略不仅可以改进数据放置的负载均衡,而且可以减少数据副本放置的时间.

关键词： Hadoop 数据放置负载均衡策略

Clinical utility of automated platelet clump count in the screening for ethylene diamine tetraacetic acid-dependent pseudothrombocytopenia

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Chinese Medical Journal 2011年第20期124卷 3353-3357页

作者： WU wei GUO Ye ZHANG lin CUI wei LI wei ZHANG Shuo Department of Laboratory Peking Union Medical College Hospitaland Chinese Academy of Medical Sciences Be~iing 100730 China

Background Platelet （PLT） clumping occurring in pseudothrombocytopenia （PTCP） can result in inaccurate PLT. Automated platelet clump count （APCC） is a quantitative parameter of platelet aggregation. In this study, we evaluated the clinical utility of APCC in the screening for platelet aggregation related ethylene diamine tetraacetic acid （EDTA）-dependent PTCP （EDTA-PTCP）. Methods A total of 105 patients and 200 healthy individuals were enrolled in this study. Blood samples were collected with dipotassium EDTA and sodium citrate respectively. ADVIA 2120 hematology analyzer was used to perform complete blood count （CBC） and APCC. Blood smears of both EDTA- and citrate-anticoagulated samples were made for microscope observation and manual PLT counting. Results In 25 patients with EDTA-PTCP patients, for EDTA-2K anticoagulated-blood, PLT was （55±6）×10^9/L, significantly lower than citrate anticoagulated blood （（186±13）×10^9/L））. APCC was （905±694）×10^9/L, significantly higher than citrate anticoagulated blood （98±37）×10^9/L. In true thrombocytopenia and healthy control groups, APCC was （63±60）×10^9/L and （69±59）×10^9/L respectively and there was no significant difference between EDTA and citrate anticoagulants. Receiver operator characteristic （ROC） curve showed both sensitivity and specificity of APCC were 96% when the cutoff value of APCC was set as 182×10^9/L. Other platelet parameters had poor performance. Conclusion The APCC has a good sensitivity and specificity in differentiating EDTA-PTCP from true thrombocytopenia compared with other platelet parameters.

关键词： automated platelet clump count thrombocytopenia hematology analyzers

基于动态带宽分配的Hadoop数据负载均衡方法

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华南理工大学学报（自然科学版） 2012年第9期40卷 42-47页

作者：林伟伟刘波华南理工大学计算机科学与工程学院广东广州510006 华南师范大学计算机学院广东广州510631

数据负载均衡对Hadoop分布式文件系统(HDFS)性能有着重要的影响,针对HDFS中默认的数据负载均衡方法存在的效率低和缺乏灵活性的不足,文中提出了一种新的动态负载均衡方法,即通过控制变量来动态分配网络带宽以达到数据负载均衡.在此基础... 详细信息

数据负载均衡对Hadoop分布式文件系统(HDFS)性能有着重要的影响,针对HDFS中默认的数据负载均衡方法存在的效率低和缺乏灵活性的不足,文中提出了一种新的动态负载均衡方法,即通过控制变量来动态分配网络带宽以达到数据负载均衡.在此基础上建立了基于控制变量的数据负载均衡数学模型.实验结果表明,文中提出的方法既能保证HDFS的数据访问性能,又能提高集群加入新节点时的数据负载均衡效率.

关键词： Hadoop 负载均衡带宽

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树型网格环境TGrid的模型及算法

华南理工大学学报（自然科学版） 2007年第1期35卷 89-93,98页

作者：林伟伟齐德昱华南理工大学计算机科学与工程学院广东广州510640

针对当前网格环境中存在的应用开发困难和管理复杂等问题,提出了一种新的基于树型结构的网格环境TGrid,它支持高性能计算、面向主题的资源共享和新一代需求建模.文中在分析讨论TGrid的特点及实现关键问题的基础上,给出了树的建立、树的... 详细信息

针对当前网格环境中存在的应用开发困难和管理复杂等问题,提出了一种新的基于树型结构的网格环境TGrid,它支持高性能计算、面向主题的资源共享和新一代需求建模.文中在分析讨论TGrid的特点及实现关键问题的基础上,给出了树的建立、树的动态重构、资源查找等关键算法,重点描述了TGrid实现大规模并行处理的动态负载平衡算法.模拟实验结果表明所提出的算法是有效的.

关键词：树型网格虚拟资源负载平衡模型算法