Nuclear Slope Parameter of pp and p Elastic Scattering in QCD Inspired Model

Based on the quark-gluon structure of nucleon and the possible existence of Odderon in strong interaction process due to gluon self-interaction, the elastic scatterings of pp and p^-p at high energies are studied. The contributions from individual terms of quark-quark, gluon-gluon interactions, quark-gluon interference, and the Odderon terms to the nuclear slope parameter B（s） are analyzed. Our results show that the QCD inspired model gives a good fit to the LHC experimental data of the nuclear slope parameter.

Back analysis for soil slope based on measuring inclination data

Based on the analysis of several objective functions,a new method was proposed.Firstly,the feature of the inclination curve was analyzed.On this basis,the soil could be divided into several blocks with different displacements and deformations.Then,the method of the soil division was presented,and the characteristic of single soil block was studied.The displacement of the block had two components:sliding and deformation.Moreover,a new objective function was constructed according to the deformation of the soil block.Finally,the sensitivities of the objective functions by traditional method and the new method were calculated,respectively.The result shows that the new objective function is more sensitive to mechanical parameters and the inversion result is close to that obtained by the large direct shear apparatus.So,this method can be used in slope back analysis and its effectiveness is proved.

Reasonable selection of yield criteria for quantitative analysis of unsaturated soil slope stability

The yield criterion parameters of the soil material change with different values of the cohesion and the angle of friction because of sustained rainfall infiltration. Based on the Mohr-Coulomb(M-C) and Drucker-Prager(D-P) yield criteria, some reasonable yield criteria selections were discussed for quantitative analysis of unsaturated soil slope stability. Moreover, a critical point was found at the effective angle of friction equaling to 16.5° by transformation of parameters related to unsaturated soil under sustained rainfall. When the effective angle of friction more than 16.5° through parameter transformation of different yield criteria under natural condition, the calculation result of the safety factor was such that: f(DP1) > f(M-C) > f(equivalent M-C) > f(DP2) > f(DP3). While the effective angle of friction less than 16.5°, through parameter transformation, the safety factors were in the following order: f(DP1) > f(M-C) > f(DP2) > f(equivalent M-C) > f(DP3). The calculated results from a case study showed that the equivalent M-C yield criterion should be the best at evaluating soil slope stability before rainfall; the DP2 yield criterion should be selected to calculate the soil slope stability at the effective angle of friction less than 16.5° under sustained rainfall. The yield criterion should be selected or adjusted reasonably to calculate the safety factor of unsaturated soil slopes before and during sustained rainfall.

Effects of Topographic Slopes on Hydrological Proecsses and Climate

Based on previous research results on river re-distribution models, a modification on the effects of topographic slopes for a runoff parameterization was proposed and implemented to the NCAR's land sur- face model (LSM). This modification has two aspects firstly, the topographic slopes cause outflows from higher topography and inflows into the lower topography points; secondly, topographic slopes also cause decrease of infiltration at higher topography and increases of infiltration at lower topography. Then changes in infiltration result in changes in soil molsture, surface fluxes and then in surface temperature, and eventual- ly in the upper atmosphere and the climate. This mechanism is very clearly demonstrated in the point bud- gets analysis at the Andes Mountains vicinities. Analysis from a regional scale perspective in the Mackenzie GEWEX Study (MAGS) area, the focus of the ongoing Canadian GEWEX program, shows that the modi- fied runoff parameterization does bring significant changes in the regional surface climate More important- ly, detailed analysis from a global perspective shows many encouraging improvements introduced by the modified LSM over the original model in simulating basic atmospheric climate properties such as thermodynamic features (temperature and humidity). All of these improvements in the atmospheric climate simulation illustrate that the inclusion of topographic effects in the LSM can force the AGCM to produce a more realistic model climate.

基于参数化组件的道路BIM模型建模技术研究

文章定义了一套“点—边—形状—组件—横断面”五级横断面的层次结构,对道路横断面的路基路面、边坡等进行参数化组件设置,提出了一种基于参数化组件的道路BIM模型通用建模方法,以实现路基路面沿线参数化布置,边坡与地形无缝结合生成多级边坡。实践表明,该方法的建模流程兼顾参数化和自由度,可提高模型建模效率,同时可以分类存储设计信息,生成信息完善的道路BIM模型,满足建模要求。

次网格地形动力效应参数化及其对降水模拟效果的影响

地形对气流的动力抬升作用是地形降水的重要产生机制之一,为了在模式中考虑地形对气流的动力抬升作用,改进模式对复杂地形区域的降水模拟效果,本文提出了一个次网格地形动力效应参数化方案。在模式中首先利用高分辨率的地形高度资料计算出次网格格点处的地形坡度、坡向,这些微观地形参数可以较为精细地描述次网格尺度地形信息;然后再根据地面气压与地形对气流动力抬升作用的关系,对地面气压倾向进行次网格修正;最后利用p-σ区域气候模式进行了三个数值试验,检验该方案对模式模拟降水能力的影响。结果表明,次网格地形动力效应参数化方案的引入,对中国区域的降水模拟有明显改进,尤其对冬、春季的降水模拟,无论是分布范围还是中心最大强度都与实况比较接近。

Modeling the dose-response rate/associations between VO2max and self-reported Physical Activity Questionnaire in children and adolescents

Background'. This study sought to explore the dose—response rate/association between aerobic fitness (VC)2max) and self-reported physical activity(PA) and to assess whether this association varies by sex, age, and weight status.Methods. VO2max was assessed using the 20・m shuttle・run test. PA was assessed using the Physical Activity Questionnaire (PAQ) for Adolescents(aged > 11 years, PAQ-A) or for Children (aged <11 years, PAQ-C). The associations between V02raax and PAQ were analyzed using analysisof covariance (ANCOVA), adopting PAQ and PAQ2 as covariates but allowing the intercepts and slope parameters of PAQ and PAQ2 tovary with the categorical variables sex, age group, and weight status.Results: ANCOVA identified a curvilinear association between VO2max and PAQ, with positive linear PAQ terms that varied for both sex andweight status but with a negative PAQ2 term of —0.39 (95% confidence interval (CI): —0.57 to —0.21) that was common for all groups in regardto age, sex, and weight status. These curvilinear (inverted U) associations suggest that the benefits of increasing PA (same dose) on VO2max isgreater when children report lower levels of PA compared to children who report higher levels of PA. These dose-response rates were alsosteeper for boys and were steeper for lean children compared to overweight/obese children.Conclusion'. Health practitioners should be aware that encouraging greater PA (same dose) in inactive and underweight children will result ingreater gains in V02max (response) compared with their active and overweight/obese counterparts.

边坡稳定性计算程序中的可视化技术

介绍了边坡稳定性分析条分法程序开发过程中的可视化关键技术,包括数据组织、建模技术以及相关的图形拓扑运算,实现了图形的精确定位、交互操作、编辑修改和拓扑分析功能,使得分析准备工作变得更为简便,为类似分析软件的开发提供经验。

WRF模式对青藏高原南坡夏季降水的模拟分析

利用中尺度数值模式WRF研究积云对流参数化方案、网格嵌套技术和模式分辨率对陡峭的青藏高原南坡夏季降水模拟的影响。对2006年7月青藏高原南坡地区降水的模拟分析表明:降水对积云对流参数化方案的选择很敏感,不同方案模拟的结果差异显著,采用Grell-Devenyi质量通量方案时的模拟效果优于其他方案。在此基础上,通过5种试验方案比较发现,使用积云对流参数化方案、提高模式分辨率和应用网格嵌套技术能改善降水强度和空间分布的模拟,组合使用时模拟的降水与观测资料更接近。它们均能改进风场,使得水汽的输送和辐合过程的模拟更加准确;还能影响大气的垂直加热状态,导致不同的对流发生,使垂直速度的分布趋于合理。未使用积云对流参数化方案时,大气湿度偏小,而模式分辨率和网格嵌套技术对大气湿度的影响不大。

浅水极限波浪几何特征的实验研究

该文通过物理模型实验,对浅水区域内的波浪在破碎前极限状态下的几何特征进行了研究。实验基于JONSWAP谱对不规则波浪进行模拟,通过对波群中出现的单体极限波浪进行捕捉并对波形进行测量而得到研究样本。为了考察底坡因素对极限波浪几何特征的影响,实验共考虑了3组大小分别为β=1/15、1/30以及1/45的地形坡度。统计结果表明,在实验所采用的坡度范围内,当地波高与水深对近岸极限波浪的影响最为显著,随着水深与波高因素变化,极限波浪的几何特征也出现明显的改变。坡度因素对极限波陡和偏度的影响很小,可以被忽略,但是对不对称度参数的影响相对比较明显,坡度越陡,不对称程度越剧烈。最后,通过参数化,本文给出了极限波浪几何特征变化的经验公式。

一种基于扩展卡尔曼滤波器的频率及频率斜率估计算法

提出一种实用扩展卡尔曼滤波器(EKF),用于极低信噪比、高动态信号的频率及频率斜率捕获。考虑滤波器的收敛性、发散抑制、捕获时间及稳态误差等指标,提出了扩展卡尔曼滤波器的参数化设计方法。计算机仿真分析了滤波器的捕获效果,结果表明,应用该设计方法,可以使频率估计具有更低的信噪比门限和更短的捕获时间。

Correlation between the charge radii difference in mirror partner nuclei and thesymmetry energy slope

A correlation between the charge radii difference of mirror partner nucleiΔR_(ch) and the slope parameter L of symmetry energy has been built to ascertain the equation of state of isospin asymmetric nuclear matter.In this work,the influences of pairing correlations and isoscalar compression modulus on theΔRch are systematically investigated based on the Skyrme energy density functional theory.The calculated results suggest that the linear correlation betweenΔR_(ch) and L is decreased by the surface pairing correlations.The slope parameter deduced from the difference of charge radii of mirror-pair nuclei ^(32)Ar-^(32)Si,^(36)Ca-^(36)S,^(38)Ca-^(38)Ar,and ^(54)Ni-^(54)Fe falls into the range of L=42.57−50.64 MeV,that is,the rather soft equation of state of asymmetric nuclear matter.Besides,the range of the slope parameter can also be influenced by the effective forces classified by various isoscalar incompressibility coefficients.

观众厅坡度设计的计算方法与运用

为观众厅的坡度设计与座椅排布提供一种具备合理性的计算方法,并可运用于grasshopper自带运算器或内嵌ghpython模块进行参数化体现。

辽东山区人工红松冠长率影响因子研究

[目的]建立包含林木竞争、地形(坡度、坡向、坡位)的不同林层的辽东山区人工红松冠长率模型,研究不同竞争水平及地形对冠长率的影响,比较林层间的冠长率差异,为辽东山区红松人工林经营奠定基础。[方法]以辽宁省清原县大边沟林场红松人工林为研究对象,基于冠长率基础模型,通过再参数化方法引入竞争因子,采用哑变量方法进一步引入地形因子,选取对模型贡献最大的地形因子,最终建立包含竞争、地形变量的不同林层间的人工红松冠长率哑变量模型,模拟了各因子对人工红松冠长率的影响。[结果]与基础模型相比,引入林木竞争、地形因子坡向的不同林层冠长率模型R^(2)_(a)提升了0.113,RMSE降低了0.012,竞争、坡向、林层对冠长率模型的贡献率(MSER)分别为14.14%、2.25%、0.16%。冠长率随林木胸径的增大而减小,随林木竞争水平的增大而增大。随林木竞争水平的增大,冠长率随树高变化规律由负增长逐渐转为正增长。经F检验,不同坡向、林层之间冠长率差异显著,变化规律为阴坡>半阳坡>阳坡,在林层间表现为上林层>下林层。[结论]地形与林木竞争因子显著影响人工红松冠长率,坡向是对人工红松冠长率影响最大的地形因子。本研究构建的包含地形与林木竞争的冠长率模型精度较高,为辽东山区红松人工林经营管理及生长量预估提供参考。

雅万高速铁路泥页岩路堑边坡工程对策研究

雅万高速铁路沿线泥页岩具有强度低、膨胀性强的特点,在降雨及干湿循环作用下极易发生顺层破坏。本文研究提出了经验参数化设计方法,并结合当地研究成果及施工过程出现的边坡失稳案例,修正了不同风化程度的泥页岩及其软弱夹层的强度设计参数。在工程对策研究方面提出了坡体加固结合坡面覆盖的工程解决方案及设计计算方法。研究成果可用于强度较低或遇水强度显著降低的岩土边坡工程。

青藏高原东南部及东坡雨滴谱特征的研究

为研究青藏高原东南部地区及东坡的云微物理特征,利用2021年青藏高原东坡峨眉山站点以及青藏高原东南部林芝站点雨滴谱仪的观测资料,分析了青藏高原东南部及其东坡不同季节的3类降水云的雨滴谱特征及典型个例降水与西南涡之间的关系。结果表明:峨眉山站点和林芝站点的主要降水类型都为层状云降水,年累计降水量较大,降水持续时间短,降水频次多;峨眉山站点4个季节对应粒子数浓度峰值的粒径为1.5 mm左右,而林芝站点4个季节对应粒子数浓度峰值的粒径为1 mm左右,其中层状云雨滴谱浓度最低,主要贡献在小粒径上。峨眉山地区的3类云降水在Gamma拟合中,与实测相比模拟较好的粒径区间在1.5~4.0 mm;而林芝站点的拟合曲线与实测曲线的趋势较为相似,模拟较好的粒径区间在1.3~4.5 mm;因此,峨眉山站点和林芝站点的雨滴谱在适当范围内是能够运用Gamma分布模拟的。伴随较深厚的气旋性涡旋出现的降水强度较大,48 h累积雨量较大,雨滴谱分布的谱宽较宽,粒子数浓度在小粒径时更高,西南涡的发生发展造成的降水对本次研究区域的雨滴谱分布有很大的影响。

利用数据库数据采用联合模型动态预测312例肝硬化患者预后的观察分析

目的分析在标准联合模型基础上添加纵向监测变量斜率项后在纵向生存数据中的动态预测效能。方法基于R 3.6.2软件JM包中的原发性胆汁肝硬化(PBC2)数据集,分别构建标准联合模型和时变斜率参数化联合模型,分析两种联合模型的拟合结果,对比两种联合模型对肝硬化患者生存率的预测效能,对患者进行个体生存率的动态预测。结果标准联合模型结果显示:log(serBilir)每纵向增加一个单位,患者发生死亡风险增加3.852 0倍(95%CI:3.152 5~4.706 3)。时变斜率参数化的联合模型结果显示:log(serBilir)每纵向增加一个单位,患者发生死亡风险增加3.135 2倍(95%CI:2.433 2~4.039 8)。纵向轨迹斜率每增加一个单位,患者死亡风险就增加17.431 9倍(95%CI:2.399 6~126.633 9),log(serBilir)纵向轨迹的斜率与肝硬化患者的死亡风险高度相关(P<0.000 1)。比较两个模型的动态预测效能,两个联合模型均表现出患者未来4年的生存率比未来2年精度要高。而时变斜率参数化联合模型的ROC曲线下面积(AUC)范围(0.714 2~0.831 1)比标准联合模型AUC范围(0.645 0~0.836 1)小,预测性能更稳定。对随机1例患者预测4年后的生存率为0.850 3(95%CI:0.481 0~0.963 9)。结论标准联合模型和时变斜率参数化联合模型均可用于分析纵向生存资料中纵向监测指标与生存结局之间的关联性,而且时变斜率参数化联合模型在满足标准联合模型的功能同时考虑了纵向监测变量轨迹斜率对生存结局的影响,具有较好的拟合优度,比标准联合模型有较高的预测性能。