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带空化器回转体空化流场研究

哈尔滨工程大学学报 2015年第7期36卷 959-964页

作者：王复峰王国玉张敏弟黄彪刘涛涛北京理工大学机械与车辆学院北京100081 装备学院昌平士官学校北京102249

为深入研究绕带空化器回转体的空化流场结构,采用试验和数值模拟的方法对带不同尺度空化器回转体的空化流动进行了研究。运用高速全流场流动显示技术获得了不同空化数下绕回转体的空泡形态,运用粒子图像测速技术(DPIV)测量了相应工况下... 详细信息

为深入研究绕带空化器回转体的空化流场结构,采用试验和数值模拟的方法对带不同尺度空化器回转体的空化流动进行了研究。运用高速全流场流动显示技术获得了不同空化数下绕回转体的空泡形态,运用粒子图像测速技术(DPIV)测量了相应工况下流场的时均速度和时均涡量分布。研究结果表明:空化器尺度对绕回转体空化流动有重要影响,对于自然空化,不同尺度空化器初生空化数不同,空化器越大越有利于空化的产生,并有利于空泡的发展;对于通气空化,在相同通气率下,绕小尺度空化器回转体产生的空泡长度大于绕大尺度空化器回转体的泡长,且绕小尺度空化器回转体容易达到稳定的超空泡状态。这是由于在大空化器后部流动分离明显,存在更加复杂的漩涡运动,从而不容易产生稳定的空泡。在相同通气率和傅汝德数下,绕带不同空化器的回转体形成的空泡形态不同,空泡的脱落方式和周期也不同。

关键词：空化器回转体通气空化空化流场数值模拟粒子图像测速技术

灌溉方式对玛纳斯河中游灌区棉花生长季棉田土壤含盐量的影响

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灌溉排水学报 2015年第11期34卷 11-17页

作者：冉圣宏陈文玲刘韬韬中国科学院地理科学与资源研究所陆地表层格局与模拟重点实验室北京100101 中国科学院研究生院北京100049 石河子大学理学院新疆石河子832000

采用田间取样、实验室分析以及统计分析等方法,对新疆玛纳斯河中游灌区漫灌、滴灌2种灌溉方式下棉田土壤含盐量在棉花全生长季的变化进行定量分析。结果表明,灌溉方式对表层土壤（0-20cm）和次深层土壤（40-60cm）含盐量影响较大,其次... 详细信息

采用田间取样、实验室分析以及统计分析等方法,对新疆玛纳斯河中游灌区漫灌、滴灌2种灌溉方式下棉田土壤含盐量在棉花全生长季的变化进行定量分析。结果表明,灌溉方式对表层土壤（0-20cm）和次深层土壤（40-60cm）含盐量影响较大,其次是深层（60-100cm）和根层土壤（20-40cm）。其中漫灌方式下土壤含盐量的最大值多出现在深层（60-100cm）或次深层（40-60cm）,在时间上含盐量最大值则出现在棉花生长期前半段（6月份或更早）;而滴灌方式下土壤含盐量的最大值多出现在根层（20-40cm）或次深层（40-60cm）,在时间上,土壤含盐量的最大值多出现在生长期的后半段（7月或以后）。对不同灌溉方式下各样点土壤含盐量数据的非参数配对样本进行检验,发现灌溉方式对土壤含盐量的影响以7月最大,其次是8月,之后分别是6月、5月、4月;从土层深度看,灌溉方式对表层（0-20cm）土壤含盐量影响最大,其次是深层（60-100cm）,之后分别是根层（20-40cm）和次深层（40-60cm）。

关键词：土壤盐渍化土壤含水率棉花生长季玛纳斯河中游灌区

A Novel Design of a Pre-separation Panel Structure to Protect Against the Impact of an Explosion in an Aircraft Plenum Chamber

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Acta Mechanica Solida Sinica 2024年第1期37卷 166-180页

作者： Zongxing liu Xiang Yang Jun liu School of Aeronautics Northwestern Polytechnical UniversityXi'an 710072China COMAC Shanghai Aircraft Design and Research Institute Shanghai 201210China

To reduce the damage of the pressurizing panel structure of a fuselage caused by an explosion at the“least risk bomb location”in an aircraft structure,a new pre-separation panel structure was designed to resist blast ***,the dynamic strain response and morphology of impact damage of the new pre-separation panel were measured in an impact damage ***,the commercial software LS-DYNA was used to calculate the propagation of the blast shock wave,and the results were compared with empirical equations to verify the rationality of the numerical calculation ***,the fluid–structure coupling method was used to calculate the damage process of the pre-separation panel structure under the impact of an explosion wave and an impact *** calculated results were in good agreement with the test results,which showed the rationality of the calculation method and the *** residual strength of the damaged pre-separation panel was significantly higher than that of the original damaged *** results show that the new pre-separation panel structure is reasonable and has certain significance for guiding the design of plenum chambers with strong resistance to implosion for aircraft fuselages.

关键词： Pre-separation panel structure Explosive response Residual strength Aircraft plenum chamber Least risk bomb location

维普期刊数据库评论

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Meta分析中连续性数据的深度提取方法

中国循证医学杂志 2017年第1期17卷 117-121页

作者：刘海宁吴昊姚灿陈玉琢刘韬韬复旦大学附属中山医院消化科上海200032

连续性数据的Meta分析需要获得各组数据的样本量、均数、标准差。无法从文献中直接获取均数、标准差时,可对数据进行深度提取。本文介绍8种对数据进行深度提取的方法,并通过2项实例分析示范其应用过程。

关键词： Meta分析连续性数据数据提取均数标准差

Effectiveness and safety of acupuncture in treatment of pregnancyrelated symptoms:a systematic review and Meta-analysis

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Journal of Traditional Chinese Medicine 2024年第1期44卷 16-26页

作者： liu Tingting liu Tongou liu Mingfu School of Traditional Chinese Medicine Clinical Medicine Hubei University of Traditional Chinese MedicineWuhan 430000China First Clinical College of Hubei University of Traditional Chinese Medicine Wuhan 430000China Department of Acupuncture and Tuina Affiliated Hospital of Hubei University of Traditional Chinese MedicineHubei Provincial Hospital of Traditional Chinese MedicineWuhan 430000China

OBJECTIVE:To systematically evaluate the efficacy and safety of acupuncture(AM)in the treatment of pregnancyrelated symptoms such as acute vomiting during ***:We comprehensively searched the available literature up to November 2021,including Pub Med,Embase,Cochrane Library,Chinese Biomedical Literature Database,and China National Knowledge Infrastructure Database,for randomized controlled trials(RCTs)on AM for the treatment of severe vomiting,insomnia,pharyngeal and pelvic pain,mood abnormalities,and dyspepsia during ***:Sixteen RCTs with a cumulative sample size of 1178 cases were *** these,964 patients were included in the *** Meta-analysis results showed that AM was more efficient than Western medicine in treating discomfort during pregnancy[odds ratio(OR)=1.19,95%confidence interval(CI)(1.11,1.28),P<0.01].AM was better than the control group in improving the visual analog scale scores[standard mean difference(SMD)=0.62,95%CI(0.53,0.71),P<0.01].AM was superior to the control group in improving Numerical Rating Scale(NRS)symptom scores[OR=7.31,95%CI(3.36,15.94),P<0.01].There was no significant difference in adverse effects between the AM and sham-AM groups and the analgesic drug group[OR=0.70,95%CI(0.39,1.28),P=0.25],but the treatment and control groups had mild adverse effects with a low ***:AM is more effective than other treatments or pharmacotherapy alone in the treatment of pregnancy-related symptoms,and is relatively ***,the quality of the included trials was rather poor,and high-quality studies are required to confirm our findings.

关键词： acupuncture pregnancy nausea vomiting sleep initiation and maintenance disorders low back pain pelvic pain mood abnormalities Meta-analysis systematic review

氧化铝溶出工序一键开停车控制系统的设计与实现

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轻金属 2018年第6期 63-67页

作者：杨琦张羽飞刘涛涛沈阳铝镁设计研究院有限公司辽宁沈阳110001

介绍了一种氧化铝管道化溶出工序一键开停车控制系统的设计方案,分别从控制系统硬件配置、顺控软件规则和现场执行机构选型方案进行了阐述。本方案自控阀门选用一体化智能电动执行机构,并配有Profibus-DP总线冗余网络机制,提高了控制信... 详细信息

介绍了一种氧化铝管道化溶出工序一键开停车控制系统的设计方案,分别从控制系统硬件配置、顺控软件规则和现场执行机构选型方案进行了阐述。本方案自控阀门选用一体化智能电动执行机构,并配有Profibus-DP总线冗余网络机制,提高了控制信号的稳定可靠性。该方案提高了溶出工序的自动化程度,降低了现场操作工人的劳动强度,缩短了开停车时间,提高生产效率。避免了开停车过程中因管道或阀门泄露等原因造成的人身安全事故,从而实现了安全、文明生产。

关键词：氧化铝管道化溶出一键开停车系统一体化智能执行机构

Stochastic Unit Commitment with High-Penetration Offshore Wind Power Generation in Typhoon Scenarios

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Journal of Modern Power Systems and Clean Energy 2024年第2期12卷 535-546页

作者： Yanqi liu Dundun liu Hongcai Zhang State Key Laboratory of Internet of Things for Smart City and Department of Electrical and Computer Engineering University of MacaoMacao 999078China University of Macao Zhuhai UM Science and Technology Research Institute ZhuhaiChina

To tackle the energy crisis and climate change,wind farms are being heavily invested in across the *** China's coastal areas,there are abundant wind resources and numerous offshore wind farms are being *** secure operation of these wind farms may suffer from typhoons,and researchers have studied power system operation and resilience enhancement in typhoon ***,the intricate movement of a typhoon makes it challenging to evaluate its spatial-temporal *** published papers only consider predefined typhoon trajectories neglecting *** address this challenge,this study proposes a stochastic unit commitment model that incorporates high-penetration offshore wind power generation in typhoon *** adopts a data-driven method to describe the uncertainties of typhoon trajectories and considers the realistic anti-typhoon mode in offshore wind farms.A two-stage stochastic unit commitment model is designed to enhance power system resilience in typhoon *** formulate the model into a mixed-integer linear programming problem and then solve it based on the computationally-efficient progressive hedging algorithm(PHA).Finally,numerical experiments validate the effectiveness of the proposed method.

关键词： Unit commitment two-stage stochastic programming offshore wind farm typhoon

Devolatilization of high viscous fluids with high gravity technology

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Chinese Journal of Chemical Engineering 2024年第7期71卷 249-257页

作者： Jibing Qi Youzhi liu Yandong liu Taiyuan University Taiyuan 030032China Shanxi Province Key Laboratory of Higee-Oriented Chemical Engineering North University of ChinaTaiyuan 030051China

Volatile organic compounds(VOCs)are generally toxic and harmful substances that can cause health and environmental *** removal of VOCs from polymers has become a key *** effective devolatilization to remove VOCs from high viscous fluids such as polymer is necessary and is of great *** this study,the devolatilization effect of a rotating packed bed(RPB)was studied by using polydimethylsiloxane as the viscous fluid and acetone as the *** devolatilization rate and liquid phase volume(KLa)have been *** results indicated that the optimum conditions were the high-gravity factor of 60,liquid flow rate of 10 L·h^(-1),and vacuum degree of 0.077 *** dimensionless correlation of KLa was established,and the deviations between predicted and experimental values were less than±28%.The high-gravity technology will result in lower mass transfer resistance in the devolatilization process,enhance the mass transfer process of acetone,and improve the removal effect of *** work provides a promising path for the removal of volatiles from polymers in combination with high-gravity *** can provide the basis for the application of RPB in viscous fluids.

关键词： High-gravity technology Devolatilization rate High viscous fluid Volatile organic compounds(VOCs)

利用HSRP技术实现核心数据设备的双机热备

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中国环境管理干部学院学报 2009年第3期19卷 96-98页

作者：刘涛滔杜勇北京交通大学电子信息学院北京100044 自贡市环境科研监测所四川自贡643000

秦皇岛渤海在线信息网络公司现行的网络中,4006负责到两个出口PIX的策略路由,到远端交换机的VLAN路由,还有不出外网的内网VLAN的交换。目前网络对4006的依赖性太强,增加一台性能更强的4506同4006做HSRP双机热备和部分业务的冷备。本文... 详细信息

秦皇岛渤海在线信息网络公司现行的网络中,4006负责到两个出口PIX的策略路由,到远端交换机的VLAN路由,还有不出外网的内网VLAN的交换。目前网络对4006的依赖性太强,增加一台性能更强的4506同4006做HSRP双机热备和部分业务的冷备。本文通过分析秦皇岛渤海在线网络公司网络现况,介绍利用HSRP技术实现核心数据设备的双机热备的实现原理和具体的实现方法。

关键词：主从双机热备 HSRP