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| 1 | FLOOD DISCHARGE AND ENERGY DISSIPATION BY JETS FROM OUTLETS IN HIGH ARCH DAM显示文摘In this thesis, the scale effect by an aerated water jet diffusing in the water upon the hydrodynamic pressure, the local riverbed scour by multiple layered jets and by those colliding in the vertical and the transverse directions, and the stability of the apron slab both in the inverted arch cushion pool and the flat bottom one by the large discharge and the high water head with 300m level are detailedly researched by means of model test and numerical simulation. A mathematic model simulating the destabilization of the flat bottomed slab is established to open out the mechanism of its stability. Both experimental researches both on the hydrodynamic pressure acted inside joints between the bedrock and the apron slab, and on forces at arch abutments in inverted arch cushion pool are carried out by using an advanced measurement and the imitation means to acquire the mechanism of the inverted arch pool to keep stability and its stability condition. | Ph.D.Candidate:Sun JianXi’an University of Technolgy, Xi’an 710048, ChinaSupervisor:Yu Changzhao (Tsinghua University, Beijing 100084, China)Li Yuzhu (Tsinghua University, Beijing 100084, China)Chen Changzhi (Tsinghua University, Beijing 100084, China)Members of Dissertation Defense Committee:Gao Jizhang (China Institute of Water Resources and Hydropower Research), ChairmanLi Guifen (China Institute of Water Resources and Hydropower Research)Cui Guangtao (Tianjing University)Wang Xingkui (Tsinghua University)Yu Changzhao (Tsinghua University)Li Yuzhu (Tsinghua University)Chen Changzhi (Tsinghua University) | 2003 | Journal of Hydrodynamics2003，15，1： | 39 |
| 2 | Spatiotemporal vegetation cover variations in the Qinghai-Tibet Plateau under global climate change显示文摘Empirical Orthogonal Function (EOF) analysis and the related Principal Components (PC) analysis are used to extract valuable vegetation cover derived information from the National Oceanic and Atmos- pheric Administration (NOAA-AVHRR)'s Leaf Area Index (LAI) satellite images. Results suggest that from 1982 to 2000 global climate change has contributed to an increase in vegetation cover in the Qinghai-Tibet Plateau. The correlation between rainfall and LAI EOF PC1 and PC2 indicates that rainfall is the major climatic factor influencing interannual variations of average vegetation cover throughout the entire Plateau. However, annual mean vegetation cover trends in the Qinghai-Tibet Plateau are mainly out of phase with air temperature increasing, which is primarily responsible for nonsynchro- nous changes of vegetation cover. In the southern ridge of the Qinghai-Tibet Plateau, recent warming trends contribute to humid weather and favorable conditions for vegetation growth. By contrast, higher temperatures have led to arid conditions and insufficient rainfall in the northern part of the Plateau, leading to drought and other climatic conditions which are not conducive to increased vegetation cover. | XU XingKui CHEN Hong Jason K LEVY | 2008 | Chinese Science Bulletin2008，53，6： | 28 |
| 3 | Influence of vegetations and snow cover on sand.dust events in the west of China显示文摘By using Normalized Difference Vegetation Index (NDVI) with the resolution of 80kmx80km, satellite remote sensing data, derived from the National Oceanic and Atmospheric Administration (NOAA) and Empirical Orthogonal Function (EOF) analysis showed that surface vegetation cover in large areas of northwest China took on a significantly increasing trend between 1982 and 1994, and decreased after 1995. The first two temporal coefficients corresponding to respective eigenvector can reflect the annual change of vegetation exactly in the west of China. The correlation analysis between NDVI and the frequency of sand storms, blowing sand and floating dust illuminate that annual change of vegetation is one of the most important factors affecting disaster weather, such as sand-dust events. Meanwhile, correlation analyses also demonstrate that the snowfall in the part of western China plays an important role in sand-dust events. In this study, the influence of vegetation and snow cover in the west of China on the frequency of sand-dust events is revealed directly in virtue of remote sensing data, weather observational data and statistical methods. | XU Xingkui CHEN Hong | 2006 | Chinese Science Bulletin2006，51，3： | 16 |
| 4 | Genetic Variation of the VP1 Gene of the Virulent Duck Hepatitis A Virus Type 1(DHAV-1) Isolates in Shandong Province of China显示文摘To investigate the relationship of the variation of virulence and the external capsid proteins of the pandemic duck hepatitis A virus type 1(DHAV-1) isolates,the virulence,cross neutralization assays and the complete sequence of the virion protein 1(VP1) gene of nine virulent DHAV-1 strains,which were isolated from infected ducklings with clinical symptoms in Shandong province of China in 2007-2008,were tested.The fifth generation duck embryo allantoic liquids of the 9 isolates were tested on 12-day-old duck embryos and on 7-day-old ducklings for the median embryonal lethal doses(ELD 50 s) and the median lethal doses(LD 50 s),respectively.The results showed that the ELD 50 s of embryonic duck eggs of the 9 DHAV-1 isolates were between 1.9 × 10 6 /mL to 1.44 × 10 7 /mL,while the LD 50 s were 2.39 × 10 5 /mL to 6.15 × 10 6 /mL.Cross-neutralization tests revealed that the 9 DHAV-1 isolates were completely neutralized by the standard serum and the hyperimmune sera against the 9 DHAV-1 isolates,respectively.Compared with other virulent,moderate virulent,attenuated vaccine and mild strains,the VP1 genes of the 9 strains shared 89.8%-99.7% similarity at the nucleotide level and 92.4%-99.6% at amino acid level with other DHAV-1 strains.There were three hypervariable regions at the C-terminus(aa 158-160,180-193 and 205-219) and other variable points in VP1 protein,but which didn't cause virulence of DHAV-1 change. | Jiming Gao Junhao Chen Xingkui Si Zhijing Xie Yanli Zhu Xingxiao Zhang Shujing Wang Shijin Jiang | 2012 | Virologica Sinica2012，27，4： | 10 |
| 5 | Three-dimensional numerical simulation of methane drainage by high-level drill holes in a lower protective coal seam with a “U” type face显示文摘Different drill-hole positions may produce different drainage results in low protective coal seams.To investigate this possibility,a 3D stope model is established,which covers three kinds of drill holes.The FLUENT computational fluid mechanics software is used to solve the mass,momentum and species conservation equations of the model.The spatial distributions of oxygen and methane was obtained by calculations and the drainage results of different drill-hole positions were compared.The results show that,from top to bottom,methane dilution by oxygen weakens gradually from the intake to the return side,and methane tends to float;methane and oxygen distribute horizontally.The high-level crossing holes contribute to better methane drainage and a greater level of control.Around these holes,the methane density decreases dramatically and a 'half circle'distribution is formed.The methane density decreases on the whole,but a proportion of the methane moves back to deep into the goaf.The research findings provide theoretical grounds for methane drainage. | Xingkui Liu Shuzhao Yang | 2014 | International Journal of Coal Science & Technology2014，1，4： | 7 |
| 6 | Experimental study on three dimensional movements of particles Ⅰ Effects of particle diameter on velocity and concentration distributions显示文摘Based on the three Dimensional Particle Tracking Velocimetry(3D PTV) system,the characteristics of motion of particles with four different diameters were investigated under the steady flow conditions. The longitudinal average velocity profiles of these particles were in accordance with Log-law,while the vertical and transverse velocities remained very low with minimal fluctuation. The time-average velocity of particles in the bed load layer was 8.50u,close to Bagnold's assumption U n-ω. The vertical concentration distribution of particles in the suspension region agreed with the Rouse equation. When the diameter of particles was relatively large,there existed an evident concentration gradient in the bed load layer. | Limo TANG Xingkui WANG | 2009 | International Journal of Sediment Research2009，24，2： | 6 |
| 7 | An approach to estimating sediment transport capacity of overland flow显示文摘Estimating sediment transport capacity of overland flow is essential to the development of physically based soil erosion models.Correlation analysis indicates that stream power is a dominant factor for sediment transport in overland flows and a new sediment transport capacity equation is proposed based on dimensional analysis.The coefficients of the new equation are calibrated using the published laboratory data,and rainfall impact is taken into consideration by adding an empirical factor on the dimensionless critical stream power.The new sediment transport capacity equation is a function of stream power,rainfall impacted critical stream power and slope.The new equation is applied in a one-dimensional soil erosion model to simulate field data of a runoff plot and the simulation results are reliable. | LI WenJie LI DanXun WANG XingKui | 2011 | Science China(Technological Sciences)2011，54，10： | 6 |
| 8 | Experimental study on three dimensional movements of particles Ⅱ Effects of particle diameter on turbulence characteristics显示文摘Based on the 3D PTV(Particle Tracking Velocimetry) measuring system,the 3D movement characteristics of particles with four different diameters were investigated. Under specific flow conditions,the impact of particle diameters on 3D motion of particles was studied,and the turbulence characteristics were analyzed by different statistical methods. The results showed that the turbulence intensity of coarse particle decreased as the diameter increased. In near wall region,the probability density distributions of longitudinal and vertical fluctuation velocities both deviated from the normal distribution;while in the outer region,the probability density distribution of vertical fluctuation velocity approximately agreed with the normal distribution. | Limo TANG Xingkui WANG | 2009 | International Journal of Sediment Research2009，24，2： | 5 |
| 9 | VELOCITY PROFILES OF SEDIMENT-LADEN FLOW显示文摘The time-average velocity profiles of the flows carrying natural sand particles and three kinds of plastic particles as suspension and neutrally buoyant load are measured and analyzed. The velocity profiles of the sediment-laden flow can approximately be divided into two regions - the near-bed region and the far-bed region. Main factors affecting the velocity profiles are viscosity, density gradient, grain shear stress and damping of turbulence due to particles. Based on these physical conceptions, a velocity profile model of sediment-laden flow is developed. It agrees well with the experimental data. The discrepancy is 1.57% for the plastic particle-laden flow and 3.67% for the natural sand-laden flow. In the far-bed region, von Karman constants are smaller than those of the clear water flow. | WANG Xingkui and QIAN Ning (N. Chien) (Associate Professor, Department of Hydraulic Engineering, Tsinghua University, Beijing,100084, China Late Professor, Department of Hydraulic Engineering, Tsinghua University, Beijing,100084, China) | 1992 | International Journal of Sediment Research1992，7，1： | 4 |
| 10 | Temporal-spatial characteristics of vegetation cover and desertification of China by using remote sensing data | XU Xingkui , LIN Zhaohui, LI Jianping and ZENG Qingcun(LASG, Institute of Atmospheric Physics, Chinese Academy of Sciences, Beijing 100029, China) | 2002 | Progress in Natural Science:Materials International2002，12，1： | 4 |
| 11 | Quantitative evaluation of NEXRAD data and its application to the distributed hydrologic model BPCC显示文摘The next-generation weather radar(NEXRAD) can generally capture the spatial variability of rainfall fields,but fails to provide accurate depth measurements.A systematic strategy to evaluate the accuracy of radar data in depth measurement and its performance in hydrologic model is outlined.Statistical evaluation coefficients are calculated by comparing NEXRAD data with individual raingauges as well as subbasin-averaged interpolations,and point-and surface-average factors are introduced to revise radar data successively.Hydrologic simulations are then performed with a distributed hydrologic model,called basin pollution calculation center(BPCC) with both raingauge observations and revised NEXRAD estimates inputs.The BPCC model is applied to Clear Creek Watershed,IA,USA,on an hourly scale,and the calibration and validation parameters are semi-automatically optimized to improve manual calibration shortcomings.Results show that hydrographs generated from both gauge and NEXRAD are in good agreement with observed flow hydrographs.Coefficient statistics reveal that NEXRAD contributes to model performance,indicating that NEXRAD data has the potential to be used as an alternative source of precipitation data and improve the accuracy of hydrologic simulations. | ZHANG HuiLan Li DanXun WANG XingKui JIANG XiaoMing | 2012 | Science China(Technological Sciences)2012，55，9： | 4 |
| 12 | Three-dimensional unstructured-mesh eutrophication model and its application to the Xiangxi River,China显示文摘The Xiangxi River is one of the main tributaries in the Three Gorges reservoir,with the shortest distance to the Three Gorges Project Dam.Severe and frequent algal bloom events have occurred frequently in the Xiangxi River in recent years.Therefore,the current study develops a three-dimensional unstructured-mesh model to investigate the dynamic process of algal bloom.The developed model comprises three modules,namely,hydrodynamics,nutrient cycles,and phytoplankton ecological dynamics.A number of factors,including hydrodynamic condition,nutrient concentration,temperature,and light illumination,that would affect the evolution of phytoplankton were considered.Moreover,the wave equation was used to solve the free surface fluctuations and vertical Z-coordinates with adjustable layered thicknesses.These values,in turn,are suitable for solving the algal bloom problems that occurred in the river style reservoir that has a complex boundary and dramatically changing hydrodynamic conditions.The comparisons between the modeling results and field data of years 2007 and 2008 indicate that the developed model is capable of simulating the algal bloom process in the Xiangxi River with reasonable accuracy.However,hydrodynamic force and external pollution loads affect the concentrations of nutrients,which,along with the underwater light intensity,could consequently affect phytoplankton evolution.Thus,flow velocity cannot be ignored in the analysis of river algal bloom.Based on the modeling results,building an impounding reservoir and increasing the releasing discharge at appropriate times are effective ways for controlling algal bloom. | Jian Li Danxun Li Xingkui Wang | 2012 | Journal of Environmental Sciences2012，24，9： | 4 |
| 13 | TLR4 inactivation protects from graft-versus-host disease after allogeneic hematopoietic stem cell transplantation显示文摘Graft-versus-host 疾病(GVHD ) 是在造血的干细胞移植以后的最普通的复杂并发症。澄清像使用费的受体的角色 4 (TLR4 ) ,它是为细菌的 lipopolysaccharides (LPS ) 的主要受体在尖锐 GVHD 的发展,我们使用了一个 TLR4 大美人(TLR4 −/−) 老鼠 GVHD 模型并且分析了内在的免疫学的机制。当 TLR4 −/− 老鼠被用作骨头髓和 splenocyte 房间接枝施主或接受者时, GVHD 症状出现和死亡被推迟与相比野类型(TLR4 +/+) 老鼠。另外,组织病理学说的分析在 TLR4 −/− BALB/c 怪物,肝和小肠织物损坏与最小的淋巴球的渗入被减少。与 TLR4 +/+, TLR4 −/− 老鼠相对照,树枝状的房间没在处于一个不成熟的状态感应、留下的 LPS 期间表示 CD80, CD86, CD40, MHC-II 或 IL-12。而且, TLR4 −/− 鼠标怒气的能力支持 allogeneic T 房间增长的树枝状的房间和,特别地 T 助手房间 1 (Th1 ) 开发显然与 TLR4 +/+ 鼠标相比被稀释 interferon-γ 的树枝状的房间,和层次;(IFN-γ) 并且 IL-10, Th2 房间特定的 cytokines,在 TLR4 −/− BALB/c 比在 TLR4 +/+ BALB/c 妄想的老鼠。总的来说,我们的数据表明 TLR4 可以在 GVHD 和基因治疗可能提供的那指向的 TLR4 的致病起一个作用减少 GVHD 的风险的一条新处理途径。 | Yi Zhao Qiuyan Liu Li Yang Donghua He Lijuan Wang Jun Tian Yi Li Fuming Zi Hanying Bao Yang Yang Yuanyuan Zheng Jimin Shi Xingkui Xue Zhen Cai | 2013 | Cellular & Molecular Immunology2013，10，2： | 4 |
| 14 | KINETIC MODELING OF CONSTITUTIVE RELATIONS FOR PARTICLE MOTION IN LOW TO MODERATELY CONCENTRATED FLOWS显示文摘Formulating underlying mechanisms of concentrated solid-liquid flows is essential for simulation of various industrial processes and natural phenomena. A generalized constitutive model for particle motion in flows with low to moderate solids concentrations is developed. This generalized model facilitates characterization of inelastic collisions, particle-fluid interactions, and shearing effects. Moderately concentrated simple shear flows of a sand-water mixture are analyzed, and comparisons of model predictions and experimental data are in good agreement. This model exhibits sound performance in characterizing particle motion for wide ranges of concentration and shear rate, and may supply a reasonable and competent alternative to previous models developed for dilute and rapid-granular flows when applied to moderately concentrated situations. The concentration approaches zero (C → 0) asymptote is observed at a relatively high shear rate in model predictions. Assumption of low collisional dissipation of the particle phase as C → 0 is more reasonable for this observation, compared to that without the interstitial fluid effect. Accurately modeling energy dissipation is important for characterizing the stability of dilute simple shear flows of solid-liquid mixtures. Incorporating friction forces will also facilitate improvement of the applicability of this generalized model to flows at extremely high concentrations. | Guangqian WANG Xudong FU Xingkui WANG | 2005 | International Journal of Sediment Research2005，20，4： | 3 |
| 15 | Modification of the Engelund bed-load formula显示文摘The classic Engelund bed-load formula involves four oversimplified assumptions concerning the quantity of particles per unit bed area that can be potentially entrained into motion,the probability of sediment being entrained into motion at a given instant,the mean velocity of bed-load motion,and the dimensionless incipient shear stress.These four aspects are reexamined in the light of new findings in hydrodynamics,and a modified bed-load formula is then proposed.The modified formula shows promise as being reliable in predicting bed-load transport rates in a wide range of flow intensities. | Zhen Meng Danxun Li Xingkui Wang | 2016 | International Journal of Sediment Research2016，31，3： | 3 |
| 16 | INCIPIENT MOTION OF COARSE PARTICLES IN HIGH GRADIENT RIVERS显示文摘In Northwest China, there are many inland rivers that are characterized by high a gradient, coarse particles, a thick pebble and gravel layer, and small discharge and shallow water depth during the flood season. In these rivers, the motion of coarse particles has an important influence on the construction of various structures related to these rivers. In this study, the law of the motion of coarse particles is investigated in high gradient rivers. First, according to the rolling mode of particle motion, the forces acting on coarse particles were analyzed, and a formula was deduced to represent the incipient drag force for uniform coarse particles in a high gradient river. The flow velocity near the river bed, resistance coefficient, and weight of a coarse particle were taken into account to obtain the formula, which indicated that the incipient drag force is not related to the sediment Reynolds number, but closely related to the Froude number, which was also true for the Maxwell formula. Next, after comparing the various criteria for incipient motion of sediment, experiments were done to obtain data and determine the incipient motion of coarse particles. Based on the experiments, it was concluded that the motion type of “embedded” coarse material belongs to the motion of contact load, and the nondimensional unit-width sediment transport rate, which was put forward by Taylor in 1971, was chosen as the criterion in this study. Finally, based on the experimental data, the drag force formula was calibrated. The computed drag force agreed well with the measured values. Moreover, the formula derived in this study was compared with the Maxwell formula, another formula to study the incipient motion of particles in step-shaped mountainous rivers. The comparison indicates that the slope is the key factor in the two formulas, and the weight is an important force on the incipient motion of coarse particles in the current formula, but not in the Maxwell formula. | Shengfa YANG Jiang HU Xingkui WANG | 2006 | International Journal of Sediment Research2006，21，3： | 2 |
| 17 | BED FORMS AND RESISTANCE PROPERTIES OF LIGHT-WEIGHT BED MATERIAL显示文摘Based on experimental results from a large tilting flume, the characteristics and de- veloping processes of bed forms of plastic particles during scouring and deposition are systematically studied. The relationships of the occurence, development and disappearence of sand waves with the flow conditions are presented. Various statistical characteristics of sand waves with different sizes and the corresponding resistance properties of different bed forms of plastic particles are obtained. These results have filled in the gaps in bed forms and resistance properties of light sediment particles. It also serves as useful reference in the design of river model tests. | WANG Guixian ,WANG Xingkui,GUO Jiachao Professor, Sediment Research Laboratory, Dept. of Hydraulic Engineering, Tsinghua University, Beijing 100084, China. Associate Professor, Dept. of Hydraulic Engineering, Tsinghua University. Assistant, Dept. of Hydraulic Engineering, Tsinghua University. | 1993 | International Journal of Sediment Research1993，8，3： | 2 |
| 18 | Bortezomib in combination with dexamethasone and subsequent thalidomide for newly-diagnosed multiple myeloma: A Chinese experience显示文摘 | Weiyan Zheng Guoqing Wei Xiujin Ye Jingsong He Li Li Wenjun Wu Jimin Shi Jie Zhang Weijia Huang Wanzhuo Xie Yi Luo Xingkui Xue Maofang Lin He Huang Zhen Cai | 2009 | Leukemia Research2009，，12： | 1 |
| 19 | Study on GIS-- based modeling of sPatialProcesses simulation 显示文摘 | LIU Xue WANG Xingkui WANG Guangqian | 1999 | Journal of Image and Graphics1999，4，6： | 1 |
| 20 | Winding loss mechanism analysis and design for new structure high-frequency gapped inductor显示文摘 | Mao Xingkui Chert Wei | 2005 | IEEE Transactions on Magnetics2005，41，10： | 1 |
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