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H2 strain attenuated live hepatitis A vaccines:protective efficacy in a hepatitis A outbreak

World Journal of Gastroenterology 2000年第6期6卷 829-832页

作者： Yu Liang Zhao Zong Da Meng Zhi Yi Xu Jun Jie Guo Shao Ai Chai Cheng Gang Duo Xuan Yi Wang Jin Feng Yao Hong Bin Liu shun xiang qi Hui Bin Zhu Department of Virology Hebei Provincial Sanitary and Antiepidemic StationBaoding 071000Hebei ProvinceChina Department of Epidemiology Shanghai Medical University.Shanghai 200032China Fucheng County Sanitary and Anti-epidemic Station Zhejiang Academy of Medical Sciences Hangzhou

AIM:To investigate the protective efficacy of H2 strain attenuated live hepatitis A vaccines (H2-strain vaccines) in hepatitis A (HA) ***:With the permission of their parents, 5551 pre-school and grade 1-3 primary school children were inoculated with 1 dose (10(6.5) TCID(50)) of H2 strain vaccines in a nonrandomized, controlled trial conducted in Fucheng County, Hebei Province in May *** 6485 children in the same grades and compatible in gender and age were enrolled as controls. Epidemiological and serological survey was conducted to evaluate the protective efficacy of the vaccines. ELISA was used to detect serum IgM ***:HA outbreak started in early May 1998, peaked in the middle of the same month, and lasted about 80 days. Overall 302 HA cases were found, 192(63.58%) were 5-9 years old. One vaccinee and 25 control cases were found to have hepatitis A, which account for 0.28% (1/356) and 5.92% (25/422) of all vaccinees and controls in the 14 villages, respectively. The protective efficacy of vaccines was 95.27% (95% CI: 85.83%-104.72%). In subjects tested for anti-HAV IgM from 13 villages, 1(0.40%) overt and 11(4.06%) asymptomatic HAV cases were found in 271 vaccinees but 21(6.69%) of overt and asymptomatic ones were found in 314 ***:H2 strain vaccines were excellent in preventing overt hepatitis A,but not so effective in preventing asymptomatic hepatitis A virus infection.A booster dose might be needed to get permanent reliable immunity.

关键词： hepatitis A/prevention and control vaccines, attenuated vaccines, inactivated viral hepatitis vaccines disease outbreaks protective efficacy

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Cross-subcarrier precoder design for massive MIMO-OFDM downlink with symplectic optimization

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Science China(Information Sciences) 2025年

作者： Yu-Xuan ZHANG An-An LU xiang-Gen XIA Xi-qi GAO National Mobile Communications Research Laboratory Southeast University Purple Mountain Laboratories Department of Electrical and Computer Engineering University of Delaware

We propose a cross-subcarrier precoder design(CSPD) for massive multiple-input multiple-output(MIMO) orthogonal frequency division multiplexing(OFDM) downlink. This work aims to significantly improve the channel estimation and signal detection performance by enhancing the smoothness of the frequency domain effective channel. This is accomplished by designing a few vectors known as the transform domain precoding vectors(TDPVs), which are then transformed into the frequency domain to generate the precoders for a set of subcarriers. To combat the effect of channel aging, the TDPVs are optimized under imperfect channel state information(CSI). The optimal precoder structure is derived by maximizing an upper bound of the ergodic weighted sum-rate(WSR) and utilizing the a posteriori beam-based statistical channel model(BSCM). To avoid the large-dimensional matrix inversion, we propose an algorithm with symplectic optimization. Simulation results indicate that the proposed cross-subcarrier precoder design significantly outperforms conventional methods.

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教育博士招生制度的现状、困境与出路

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黑龙江高教研究 2025年第1期43卷 98-103页

作者：韦卫起航李祥贵州交通职业大学贵州贵阳551400 西北师范大学甘肃兰州730070 贵州师范大学贵州贵阳550025

教育博士高质量发展是教育强国的战略机遇和教育博士招生规模扩大的时代诉求,完善教育博士招生制度是把好教育博士人才培养“入口关”的重要问题,是提升教育博士人才培养质量的开端。基于2024年31所高校教育博士的招生文本分析可以发现... 详细信息

教育博士高质量发展是教育强国的战略机遇和教育博士招生规模扩大的时代诉求,完善教育博士招生制度是把好教育博士人才培养“入口关”的重要问题,是提升教育博士人才培养质量的开端。基于2024年31所高校教育博士的招生文本分析可以发现,当前教育博士招生制度设计从实质正义和程序公平两个方面体现正义属性,但还存在选拔标准学博趋同、招生指标分配不均、类型特征不够凸显等问题。教育博士招生制度改革,要扣准教育博士类别要求和人才规格定位,从选拔标准应差异化、招生指标应动态化、评价标准应科学化等方面,进一步回应满足面向2035的卓越教师和教育家型教师培养需要。

关键词：教育博士招生制度程序公平实质正义内容分析法

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河北省2010-2015年重症手足口病流行特征及时空聚集性分析

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国际病毒学杂志 2017年第1期24卷 30-36页

作者：苏通刘莹莹于秋丽赵文娜谢赟齐顺祥李琦河北省疾病预防控制中心病毒病防治所石家庄05002l

目的了解河北省2010-2015年重症手足口病（HFMD）流行特点及时空聚集性。方法收集河北省2010-2015年HFMD监测数据，描述重症HFMD流行病学特征，应用GeoDa1．8．10进行空间自相关分析，SaTScanTM9．4．2进行时空聚集性分析，ArcGIS10．2... 详细信息

目的了解河北省2010-2015年重症手足口病（HFMD）流行特点及时空聚集性。方法收集河北省2010-2015年HFMD监测数据，描述重症HFMD流行病学特征，应用GeoDa1．8．10进行空间自相关分析，SaTScanTM9．4．2进行时空聚集性分析，ArcGIS10．2软件绘制专题地图进行结果可视化展示。结果河北省2010-2015年共报告重症HFMD病例3641例，平均重症率0．85／10^5，其中2010年重症率最高（2．49／10^5），疫情波动呈“大小年”现象，5-7月发病高峰，季节分布明显，总体呈下降趋势。专题地图及空间自相关分析显示，各县区HFMD重症率差异较大，地区聚集性明显（Moran’s I〉0，P〈0．05）。局部自相关分析显示，高值聚集区随时间变化较大，主要分布在河北省的中部和南部的部分地区。时空扫描分析确证，河北省南部邢台地区（隆尧县为中心，方圆60．96公里，20个区县）为最大可能聚集区（RR=38．08，LLR=1267．00，P〈0．001）；次级高发聚集区集中在省会石家庄西北部（14个县区，RR=12．35）、沧州（16个，RR=11．35）、廊坊（8个，RR=44．04）和承德（17个，RR=10．32）等地区，其发病风险RR均在10以上，聚集时间主要集中在2010-2012年5-8月。2013-2015年重症数下降明显，唐山、邯郸、张家口和保定的大部分地区为低发聚集区（RR〈1）。另对2207例实验室确诊病例病原构成分析显示，河北省重症HFMD病例仍以EV71（79．70％）感染为主。结论河北省2010-2015年重症HFMD报告发病率存在时空聚集性，聚集地区主要集中在河北省的中南部地区，但总体疫情呈现波动下降趋势。

关键词：重症手足口病流行特征时空聚集性

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不同湍流模型对环形射流泵流场模拟的影响

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郑州大学学报（工学版） 2025年第1期46卷 113-118,125页

作者：向伟宁陈云良熊顺张艳四川大学水利水电学院四川成都610065

为准确反映环形射流泵吸入室内流体剧烈的动量交换对流场的影响,将RNG k-ε(RNG)、Realizable k-ε(RKE)、RSM、Standard k-ω(SKW)、SST k-ω(SST)这5种湍流模型和3种壁面处理方法进行组合对比计算,并开展水力实验进行验证。结果表明:... 详细信息

为准确反映环形射流泵吸入室内流体剧烈的动量交换对流场的影响,将RNG k-ε(RNG)、Realizable k-ε(RKE)、RSM、Standard k-ω(SKW)、SST k-ω(SST)这5种湍流模型和3种壁面处理方法进行组合对比计算,并开展水力实验进行验证。结果表明:不同壁面函数对环形射流泵性能和壁面压力系数的计算影响很小;相较于RNG、SKW、SST,RKE模型或RSM模型结合可扩展壁面函数(ScWF)的计算结果与实测更吻合。对比模拟流场发现:低流量比工况下不同湍流模型性能预测结果与模拟的回流区分布范围相关,模拟出来的回流区范围越大,预测的环形射流泵性能越低。基于熵产理论分析认为,环形射流泵的能量损失主要源于分布在壁面和混合剪切层的湍动熵产,高流量比工况下RSM模型计算得到的湍动熵产率偏高,是其预测性能低于RKE模型的主要原因。

关键词：环形射流泵湍流模型性能回流区熵产理论

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Partial penetration of annular grooved projectiles impacting ductile metal targets

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Defence Technology（防务技术） 2021年第4期17卷 1115-1125页

作者： qi Huang shun-shan Feng Xu-ke Lan qing Song Tong Zhou Yong-xiang Dong State Key Laboratory of Explosion Science and Technology Beijing Institute of TechnologyBeijing100081China

Changing and optimizing the projectile nose shape is an important way to achieve specific ballistic *** special ballistic performance is the embedding effect,which can achieve a delayed high-explosive reaction on the target *** embedding effect includes a rebound phase that is significantly different from the traditional penetration *** better study embedment behavior,this study proposed a novel nose shape called an annular grooved projectile and defined its interaction process with the ductile metal plate as partial ***,we conducted a series of lowvelocity-ballistic tests in which these steel projectiles were used to strike 16-mm-thick target plates made with 2024-O aluminum *** observed the dynamic evolution characteristics of this aluminum alloy near the impact craters and analyzed these characteristics by corresponding cross-sectional views and numerical *** results indicated that the penetration resistance had a brief decrease that was influenced by its groove structure,but then it increased significantlydthat is,the fluctuation of penetration resistance was affected by the irregular nose ***,we visualized the distribution of the material in the groove and its inflow process through the rheology lines in microscopic tests and the highlighted mesh lines in *** combination of these phenomena revealed the embedment mechanism of the annular grooved projectile and optimized the design of the groove shape to achieve a more firm embedment *** embedment was achieved primarily by the target material filled in the groove ***,preventing the shear failure that occurred on the filling material was key to achieving this embedding effect.

关键词： Partial penetration Embedment behavior Ballistic impact Annular grooved projectile(AGP) Microscopic experiments

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Propagation Characteristics of Plane Explosion Wave in Layered Concrete Media

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兵工学报 2015年第S1期36卷 228-232页

作者： DONG Yong-xiang SONG qi LU Zhi-chao CUI Miao FENG shun-shan State Key Laboratory of Explosion Science and Technology Beijing Institute of Technology

Layered concrete media with different wave impedance materials under one-dimensional strain are studied by numerical simulation. The four typical prototypes are analyzed,including concrete foam,air,steel plate and concrete as the middle layer,and the upper and lower layers are concrete materials. The propagation characteristics of plane blast wave in the concrete structure are illustrated,including the propagation and attenuation of stress wave across the different interlayers,the wave reflection and transmission at layered interfaces,the peak value of stress in the lower concrete and the total energy distribution in various medium layers. The result shows that the role of soft interlayer in concrete structure is mainly due to its low wave impedance,the waveform of incident wave is changed,the stress wavelength is pull wide,the radial diffusion of energy is enhanced,and the stress amplitude of and the energy input into the third layer are reduced. Meanwhile,it has been also proved that the air interlayer is able to reduce the peak value of explosion wave which is obviously different from that of foamed material. As a result,it should be concerned about stress amplitude and energy in order to get the best protective structure.

关键词： explosion wave layered concrete wave impedance numerical simulation

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Firm embedding behavior of annular grooved projectiles impacting ductile metal targets

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Defence Technology（防务技术） 2019年第5期15卷 768-778页

作者： qi Huang shun-shan Feng Xu-ke Lan Chao-nan Chen Yong-xiang Dong Tong Zhou State Key Laboratory of Explosion Science and Technology Beijing Institute of Technology

Annular grooved projectiles(AGPs)have drawn ongoing concerns as an advanced penetrator for their excellent anti-rebound capability in impacting metal *** could become embedded solidly in the target surface during low-velocity *** this investigation,the firm embedding behavior of AGP was observed by impact *** numerical simulations provided a better understanding of this *** and numerical results indicated that the firm embedding behavior of AGP was mainly due to the filling-material in the groove rather than the friction between the projectile and target,unlike traditional shape such as conical *** to observation,firm embedding process can generally be subdivided into four stages:initial-cratering stage,groove-filling stage,fillingmaterial failure stage and rebound vibration ***,the damage mechanics of target material around crater was obtained through microscopic tests.A comparison of the cross-sectional figures between the experiment and simulation proved that the analysis and the proposed method were reasonable and feasible,which further demonstrated that the firm embedding behavior has application potential in new concept warheads.

关键词： Annular grooved projectile (AGP) Impact Firm embedding behavior Flow characteristics Microscopic tests

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Determination of the Refractive Index Profile of a Polymer Waveguide by Photobleaching

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Chinese Physics Letters 2000年第6期17卷 433-434页

作者： SHAN Ji-xiang SHEN qi-shun ZHANG Ai-Hua CAO Zhuang-qi CHEN Ying-Li Department of Applied Physics Jiao Tong UniversityShanghai 200030

The shrinkage effect of polymer films,which was demonstrated in our photobleaching experiment,can be fitted approximately by an exponentially decaying *** taking the shrinkage effect into account,the index profile of the polymer waveguide was determined to be a Fermi function with the help of the m-line method and the exact transfer matrix theory.

关键词： function waveguide Waveguide

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Predicting coastal morphological changes with empirical orthogonal function method

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Water Science and Engineering 2016年第1期9卷 14-20页

作者： fernando alvarez shun-qi pan Hydro-environmental Research Centre School of Engineering Cardiff University Cardiff CF24 3AA UK

In order to improve the accuracy of prediction when using the empirical orthogonal function （EOF） method, this paper describes a novel approach for two-dimensional （2D） EOF analysis based on extrapolating both the spatial and temporal EOF components for long-term prediction of coastal morphological changes. The approach was investigated with data obtained from a process-based numerical model, COAST2D, which was applied to an idealized study site with a group of shore-parallel breakwaters. The progressive behavior of the spatial and temporal EOF components, related to bathymetric changes over a training period, was demonstrated, and EOF components were extrapolated with combined linear and exponential functions for long-term prediction. The extrapolated EOF components were then used to reconstruct bathymetric changes. The comparison of the reconstructed bathymetric changes with the modeled results from the COAST2D model illustrates that the presented approach can be effective for long-term prediction of coastal morphological changes, and extrapolating both the spatial and temporal EOF components yields better results than extrapolating only the temporal EOF component.

关键词： EOF method Coastal morphological change Long-term prediction Process-based numerical model Shore-parallel breakwater

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