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Chinese Physics letters 1996年第6期13卷 473-476页

作者： WANG Jian-jun lÜfan-xiu Department of Materials Science and Engineering Beijing University of Science and TechnologyBeijing 100083

Effect of oxygen addition on diamond film deposition at higher pressure was *** was found that addition of oxygen suppressed diamond nucleation,and the effect of suppression increased with increasing pressure,and at certain pressure level diamond deposition was completely *** effect due to oxygen addition dominated at the very early stage(nucleation stage),therefore it is still possible to take the advantage of oxygen addition on quality improvement of diamond films by introducing oxygen after the nucleation stage.

关键词： Diamond Oxygen effect

STRESS ANAlYSIS OF THE APERTURE IN COMPOUND PIPElINE BY FEM

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Acta Metallurgica Sinica(English letters) 2007年第5期20卷 385-390页

作者： J.G. Yang H.Y. fang C.l. fan Z. luo X.Z. Hou State Key laboratory of Advanced Welding Production Technology Harbin Institute of Technology Harbin 150001 China School of Material Science and Engineering Tianjin University Tianjin 300072 China Daqing Oil-Ghem-Wdding Institute Daqing 163712 China

There is a cyclical aperture at a certain part of the fiberglass reinforced plastic compound pipeline with a stainless steel pipe as a liner, which becomes the weakness of the conduit. The field of stress and strain of the aperture was investigated using the nonliner finite element code Marc. The results of the finite element analysis showed that there were concentrations of stress and strain in the layer of stainless steel at the part of the pipeline where the aperture existed. The method to solve these problems was also discussed.

关键词： compound pipeline stress software Marc

Complete Universal Scaling in First-Order Phase Transitions

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Chinese Physics letters 2024年第10期41卷 8-13页

作者： fan Zhong School of Physics and State Key laboratory of Optoelectronic Materials and Technologies Sun Yat-sen UniversityGuangzhou 510275China

Phase transitions and critical phenomena are among the most intriguing phenomena in nature and *** are classified into first-order phase transitions(FOPTs)and continuous *** the latter shows marvelous phenomena of scaling and universality,whether the former behaves similarly is a long-standing controversial *** we definitely demonstrate complete universal scaling in field driven FOPTs for langevin equations in both zero and two spatial dimensions by rescaling all parameters and subtracting nonuniversal contributions with singular dimensions from an effective temperature and a special field according to an effective *** offers a perspective different from the usual nucleation and growth but conforming to continuous phase transitions to study FOPTs.

关键词： theory. transitions scaling

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鼓泡塔中驻波声场调制大气泡的直接模拟

应用基础与工程科学学报 2007年第2期15卷 217-225页

作者：李彦鹏 fan l.S. 长安大学环境科学与工程学院陕西西安710064 俄亥俄州立大学化学与分子生物工程系

采用直接数值模拟的方法,同时计算了鼓泡塔中高频驻波的生成、传播和一个直径5.55mm的大气泡与该驻波相互影响的行为.气液主流场采用考虑表面张力的粘性可压缩流体动力学基本方程和气液两相的状态方程来描述,可压缩气泡的界面行为由leve... 详细信息

采用直接数值模拟的方法,同时计算了鼓泡塔中高频驻波的生成、传播和一个直径5.55mm的大气泡与该驻波相互影响的行为.气液主流场采用考虑表面张力的粘性可压缩流体动力学基本方程和气液两相的状态方程来描述,可压缩气泡的界面行为由levelset方法耦合界面作用模型来处理,驻波声场通过与时间相关的传感器速度入口边界条件形成.模拟结果显示,反应器中形成了一个稳定的驻波声场;由于气泡的存在,均匀的压力场变成了轴对称分布的压力场;气泡容积以很小的振幅周期性收缩与膨胀.模拟结果还揭示了对于在驻波声场中的大尺寸气泡,Bjerknes力与浮力之比为20%—25%,与实验结果21%基本相符.

关键词：驻波声场气泡 Bjerknes力可压缩气液两相流

Semi-analytical Solutions for Wellbores with Graded Skin Zones in Poroelastic Media

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Acta Mechanica Solida Sinica 2024年第3期37卷 385-395页

作者： Zhiqiang fan Zhihe Jin School of Mechanics Civil Engineering and ArchitectureNorthwestern Polytechnical UniversityXi’an710072China Department of Mechanical Engineering University of MaineOronoME04469USA

In analyzing the complex interaction between the wellbore and the reservoir formation,the hydromechanical properties of the region proximal to the wellbore,referred to as the“wellbore skin zone”,play a pivotal role in determining flow dynamics and the resulting formation *** models of the wellbore skin zone generally assume a constant permeability throughout,resulting in a sharp permeability discontinuity at the skin-reservoir *** paper introduces a model for a wellbore with a continuously graded skin zone of finite thickness within a poroelastic *** solutions are derived using the laplace transform method,addressing both positive and negative skin *** results are presented to illustrate the effects of graded permeability/skin zone thickness on pore pressures and stresses around a *** results highlight a distinct divergence in stress and pore pressure fields when comparing wellbores with negative skin zones to those with positive skin zones or no skin at all.

关键词： Poroelastic Graded permeability Analytical solution Wellbore Skin zone

Epidemiologic study on human immunodeficiency virus infection among children in a former paid plasma donating community in China

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Chinese Medical Journal 2005年第9期118卷 720-724页

作者： WANGlan ZHENGXi-wen QIANHan-zhu lüfan XINGHui DepartmentofEpidemiology NationalCenterforAIDS／STDControlandPreventionChineseCenterforDiseaseControlandPreventionBeijing100050China DepartmentofEpidemiology UniversityofAlabamaatBirminghamBirminghamAL35294-1150USA

Background Illegal plasma collecting activities in mid 1990s caused a large number of human immunodeficiency virus (HIV) infections in rural areas of central-eastern China. Although most of these activities have been stopped, there were few reports on secondary transmission from infected former plasma donors to their spouses and from infected mothers to their children. This study was to determine the extent of HIV infections among young children in a rural community with a large proportion of plasma *** A survey was conducted among children aged under 7 years in a former plasma donating community in September 2000: finger blood was collected for HIV antibody testing. Another survey was repeated among children aged under 8 years and their families in the same community in April 2001: urine samples were collected for HIV testing. HIV positive children and samples of HIV negative children, whose mothers were positive based on 2001 survey, were followed up until September 2002 to investigate HIV seroconversion, disease progression and HIV strain analysis. Questionnaires were administered to collect information on children’s delivery, breast feeding, medical history and their parents’ commercial blood donation history and HIV *** Among 169 children surveyed in 2000, 10 (5.9%) were HIV positive. Of 224 children, 11 were positive in 2001. The overall prevalence rate in the two surveys was 5.0% (17/337) when counting 56 repeated children only once. Of children born to HIV positive mothers, 28.9% were infected. A seroconversion rate of 2.5 per 100 child-years was observed by following up 28 HIV negative children. No statistically significant associations were found between children’s HIV infection and their histories of blood transfusion, surgery, immunization injection or medical injections. All infections were HIV-1 subtype B’ strain, the average dispersion rate is 7.4%. DNA sequence analysis showed a close relationship between the sero

关键词： human immunodeficiency virus · prevalence · child · vertical transmission

基于优化奇偶重构法的光伏阵列自适应重构技术设计

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聊城大学学报（自然科学版） 2024年第2期37卷 19-33页

作者：易灵芝程斯岳王雅慧罗伯特范律谭靖萱湘潭大学自动化与电子工程学院&湖南省多能源协同控制技术工程研究中心湖南湘潭411105 湖南大学电气与信息学院湖南长沙410082 威胜信息技术股份有限公司湖南长沙410205

对于光伏阵列而言,阴影遮挡和阵列损坏会导致其输出功率降低。为了提升光伏阵列的输出功率,提出了一种优化的奇偶重构方法(Optimized Odd Even Configuration,OOEC),纠正了奇偶重构法(Odd Even Configuration,OEC)在局部阴影超过4列时,... 详细信息

对于光伏阵列而言,阴影遮挡和阵列损坏会导致其输出功率降低。为了提升光伏阵列的输出功率,提出了一种优化的奇偶重构方法(Optimized Odd Even Configuration,OOEC),纠正了奇偶重构法(Odd Even Configuration,OEC)在局部阴影超过4列时,重构效果差的缺点。所提出的方法将光伏阵列分为自由重构模块和固定重构模块,根据不同的阴影情况调整连接方式,确定最佳的连接关系,并与Arrow So Du ku,Zig-zag,OEC三种方法进行仿真实验对比,仿真结果表明,经过OOEC重构后的光伏阵列输出功率明显提高,光伏阵列的PU输出特性曲线更加趋向于单峰,并且从失配损耗,功率提升百分比,性能比,均衡指数上看来,OOEC有着更好的性能。

关键词：光伏阵列静态重构 OOEC方法自由重构模块固定重构模块

A progressive framework for rotary motion deblurring

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Defence Technology（防务技术） 2024年第2期32卷 159-172页

作者： Jinhui Qin Yong Ma Jun Huang fan fan You Du School of Electronic Information Wuhan UniversityWuhan430072China

The rotary motion deblurring is an inevitable procedure when the imaging seeker is mounted in the rotating *** rotary motion deblurring methods suffer from ringing artifacts and noise,especially for large blur *** solve the above problems,we propose a progressive rotary motion deblurring framework consisting of a coarse deblurring stage and a refinement *** the first stage,we design an adaptive blur extents factor(BE factor)to balance noise suppression and details *** a novel deconvolution model is proposed based on BE *** the second stage,a triplescale deformable module CNN(TDM-CNN)is designed to reduce the ringing artifacts,which can exploit the 2D information of an image and adaptively adjust spatial sampling *** establish a standard evaluation benchmark,a real-world rotary motion blur dataset is proposed and released,which includes rotary blurred images and corresponding ground truth images with different blur *** results demonstrate that the proposed method outperforms the state-of-the-art models on synthetic and real-world rotary motion blur *** code and dataset are available at https://***/JinhuiQin/RotaryDeblurring.

关键词： Rotary motion deblurring Progressive framework Blur extents factor TDM-CNN

Seismic response of pile-supported structures considering the coupling of inertial and kinematic interactions in different soil sites

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Frontiers of Structural and Civil Engineering 2024年第9期18卷 1350-1361页

作者： Huiling ZHAO fan ZHANG Department of Civil Engineering Shanghai UniversityShanghai 200444China

Dynamic soil−pile−superstructure interaction is crucial for understanding pile behavior in earthquake-prone *** the safety of piles requires determining the seismic bending moment caused by combined inertial and kinematic interactions,which is *** paper addresses this problem through numerical simulations of piles in different soil sites,considering soil *** reveal that the period of the soil site significantly affects the interaction among soil,piles,and *** moments in soft and hard soil sites exceed those in medium soil sites by more than *** modes of piles exhibit distinct characteristics between hard and soft soil *** soil sites exhibit a singular inflection point,while hard soil sites show two inflection *** soft soil sites,pile-soil kinematic interaction gradually increases bending moment from tip to head,with minor influence from superstructure’s inertial *** hard soil sites,significant inertial effects from soil,even surpassing pile-soil kinematic effects near the tip,lead to reversed superposition bending ***’s inertial interaction notably impacts pile head in hard soil sites.A simplified coupling method is proposed using correlation coefficient to represent inertial and kinematic *** findings provide insights into complex seismic interactions among soil,piles,and structures.

关键词： pile seismic response soft soil inertial interaction kinematic interaction

Impact of non-ideal UE hardware on cell-free massive MIMO network with centralized operation

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Science China(Information Sciences) 2024年第4期67卷 255-271页

作者： Ning lI Pingzhi fan Institute of Mobile Communications Southwest Jiaotong University

This paper investigates the impact of non-ideal user equipment(UE) hardware on a cell-free(CF) massive MIMO(mMIMO) network with centralized operation under spatially correlated channels. The minimum mean-squared error(MMSE) estimator can be derived with the help of the generic non-ideal UE hardware model. It is demonstrated that even if the effective signal-to-noise ratio approaches infinity, pilot contamination and imperfect hardware can cause a non-zero estimation error floor. After that, a lower bound is determined for the ergodic uplink capacity of the centralized CF mMIMO network under non-ideal UE hardware. Moreover, the optimal receive combining vector is obtained to maximize the uplink spectral efficiency(SE). The maximum ratio(MR) and regularized zero-forcing(RZF) combining schemes are offered as alternatives in light of the computational complexity of the MMSE receiver. Comparing the RZF to the MMSE scheme under different levels of hardware impairments, our findings indicate that the RZF receiver suffers a negligible loss in total SE. For MR combining, a novel closed-form uplink achievable SE expression is obtained based on the MMSE estimator and the use-and-then-forget bounding technique. This expression gives vital insights into the achievable uplink performance with UE hardware impairments. Besides, for various hardware impairment factors, the impact of pilot sequence length on average sum SE is disclosed for different receive combining schemes. To increase the overall SE of the max-min fairness scheme, a heuristic fractional power control scheme with UE hardware impairments is developed, which can essentially avoid sacrificing the SE of other UEs while maximizing the SE of the unluckiest UE in the whole network. Finally,our theoretical performance analysis and power control algorithm are validated by simulation results, and fundamental design guidelines are provided for selecting hardware satisfying the practical UE requirements.

关键词： cell-free massive MIMO centralized operation spatially correlated channels hardware impairments channel estimation uplink spectral efficiency optimal receive combining pilot length design fractional power control