A vector sum analysis method for stability evolution of expansive soil slope considering shear zone damage softening

Slope stability analysis is a classical mechanical problem in geotechnical engineering and engineering geology.It is of great significance to study the stability evolution of expansive soil slopes for engineering construction in expansive soil areas.Most of the existing studies evaluate the slope stability by analyzing the limit equilibrium state of the slope,and the analysis method for the stability evolution considering the damage softening of the shear zone is lacking.In this study,the large deformation shear mechanical behavior of expansive soil was investigated by ring shear test.The damage softening characteristic of expansive soil in the shear zone was analyzed,and a shear damage model reflecting the damage softening behavior of expansive soil was derived based on the damage theory.Finally,by skillfully combining the vector sum method and the shear damage model,an analysis method for the stability evolution of the expansive soil slope considering the shear zone damage softening was proposed.The results show that the shear zone subjected to large displacement shear deformation exhibits an obvious damage softening phenomenon.The damage variable equation based on the logistic function can be well used to describe the shear damage characteristics of expansive soil,and the proposed shear damage model is in good agreement with the ring shear test results.The vector sum method considering the damage softening behavior of the shear zone can be well applied to analyze the stability evolution characteristics of the expansive soil slope.The stability factor of the expansive soil slope decreases with the increase of shear displacement,showing an obvious progressive failure behavior.

A Hybrid ESA-CCD Method for Variable-Order Time-Fractional Diffusion Equations

In this paper, we study the solutions for variable-order time-fractional diffusion equations. A three-point combined compact difference (CCD) method is used to discretize the spatial variables to achieve sixth-order accuracy, while the exponential-sum-approximation (ESA) is used to approximate the variable-order Caputo fractional derivative in the temporal direction, and a novel spatial sixth-order hybrid ESA-CCD method is implemented successfully. Finally, the accuracy of the proposed method is verified by numerical experiments.

Nash Equilibrium of a Fixed-Sum Two-Player Game

It is well established that Nash equilibrium exists within the framework of mixed strategies in strategic-form non-cooperative games. However, finding the Nash equilibrium generally belongs to the class of problems known as PPAD (Polynomial Parity Argument on Directed graphs), for which no polynomial-time solution methods are known, even for two-player games. This paper demonstrates that in fixed-sum two-player games (including zero-sum games), the Nash equilibrium forms a convex set, and has a unique expected payoff. Furthermore, these equilibria are Pareto optimal. Additionally, it is shown that the Nash equilibrium of fixed-sum two-player games can theoretically be found in polynomial time using the principal-dual interior point method, a solution method of linear programming.

Slope stability analysis under seismic load by vector sum analysis method

The vibration characteristics and dynamic responses of rock and soil under seismic load can be estimated with dynamic finite element method （DFEM）. Combining with the DFEM, the vector sum analysis method （VSAM） is employed in seismic stability analysis of a slope in this paper. Different from other conventional methods, the VSAM is proposed based on the vector characteristic of force and current stress state of the slope. The dynamic stress state of the slope at any moment under seismic load can he obtained by the DFEM, thus the factor of safety of the slope at any moment during earthquake can be easily obtained with the VSAM in consideration of the DFEM. Then, the global stability of the slope can be estimated on the basis of time-history curve of factor of safety and reliability theory. The VSAM is applied to a homogeneous slope under seismic load. The factor of safety of the slope is 1.30 under gravity only and the dynamic factor of safety under seismic load is 1.21. The calculating results show that the dynamic characteristics and stability state of the slope with input ground motion can be actually analyzed. It is believed that the VSAM is a feasible and practical approach to estimate the dynamic stability of slopes under seismic load.

LA-ICP-MS Calibrations for Intact Rock Samples with Internal Standard and Modified Constant-Sum Methods

Laser ablation coupled with inductively coupled plasma-mass spectrometry (LA-ICP-MS) calibration was conducted with multiple spot analyses on eleven intact rock samples using both an internal standard (IS) method and a modified constant-sum (MCS) method. Methods were then compared for reported bulk elemental composition of the rocks. The MCS method was based on the sum of eight major elements, which is spatially more stable than one single major ele-ment as used in the IS method, and is quite constant among different rock samples. Calibrations were performed with standard reference materials NIST SRM 610, 612, 614, and 616. Little difference was found between using a single standard and a set of standards, because of the good linearity shown by the reference materials. Comparison of the two calibration methods shows that the MCS method produced better and more stable results than the IS method for heterogeneous samples. With the MCS method, approximately 94% to 95% of the total measurements are within the range of ±100% relative deviation, compared with 82% to 86% with the IS method. The IS method resulted insubstantial overestimations for some rock samples (e.g., 648% for Basalt BCR-2 using NIST SRM 610 as the calibration standard), while the largest deviation with the MCS method was 216% for U in Eagle Ford shale #80 sample. For Quartz latite QLO-1, a relative homogeneous sample, the IS method generated slightly better results than the MCS method. Regardless of method, spatially heterogeneous distribution of elements in the intact rock at the scale of the laser spot is considered to be the main reason for the large relative deviations seen in our work compared to published results.

Polynomial Time Method for Solving Nash Equilibria of Zero-Sum Games

There are a few studies that focus on solution methods for finding a Nash equilibrium of zero-sum games. We discuss the use of Karmarkar’s interior point method to solve the Nash equilibrium problems of a zero-sum game, and prove that it is theoretically a polynomial time algorithm. We implement the Karmarkar method, and a preliminary computational result shows that it performs well for zero-sum games. We also mention an affine scaling method that would help us compute Nash equilibria of general zero-sum games effectively.

基于视觉信息加工的草原公路行车安全性分析

为探究草原公路各典型行车环境驾驶人视觉信息加工模式的差异性,从视觉层面解析草原公路行车安全,基于眼动仪开展草原公路实车实验,提取驾驶人在自由行驶、跟驰、对向来车、后车切入、路侧风险、交叉口6种真实行车环境下的眼动数据。首先,从视觉分配和视觉搜索两个维度构建评价指标体系,采用动态聚类法将驾驶人的视觉兴趣区域划分为5类,将信息熵与马尔可夫链平稳分布理论结合,构建视点分布信息熵量化驾驶人视觉注意分配的复杂度,并引入扫视幅度、扫视速度分析驾驶人对视觉信息的搜索过程。最后,构建基于CRITIC法的加权秩和比评价模型,对不同行车环境下驾驶人的视觉信息加工强度进行了综合评价。结果显示:驾驶人的视点分布在不同行车环境中存在差异,但当前车道始终是驾驶人获取视觉信息的主视区;各视觉评价指标随行车环境的变化呈显著的统计学差异;驾驶人遇到路侧风险时的视觉信息加工强度最大,行车安全性相对更低。

单圈图的D(2)-点和可区别全染色

图G的D(2)-点和可区别全染色是指在图G的一个正常全染色φ下,G中任意两个距离不超过2的顶点u,v,其色集合中所有颜色数之和互不相同.使得G有一个k-D(2)-点和可区别全染色的最小整数k,称为图G的D(2)-点和可区别全色数.文中应用组合零点定理和权转移方法刻画了单圈图的D(2)-点和可区别全染色,并得到其D(2)-点和可区别全色数.

世界高水平男子排球比赛攻防能力的等级评价研究——以2022世界排球锦标赛为例

以2022世界男排锦标赛24支队伍为研究对象,运用文献资料法、录像分析法和数理统计法等研究方法,对各国男排攻防指标进行等级评价,分析中国队与世界强队的攻防能力。结果显示:各队伍的进攻、防守和攻防WRSR值分布在B、C、D三个水平,波兰、巴西、法国、乌克兰、阿根廷、塞尔维亚、荷兰队的进攻WRSR值位于B级,中国队为C级。防守和攻防WRSR值达到B级水平的队伍仅为前4强,中国队虽均为D级,但处于D级的中上游水平。各队进攻、防守和攻防WRSR值与最终排名均呈显著相关,具有统计意义(P<0.01)。2022年世界男排锦标赛各队共分为5档,防守和攻防能力第1档的队伍均包括前4强,这4支队伍代表了现今世界排球队伍的最高水平。前4强的意大利队和斯洛文尼亚队的进攻能力分别位于第2和第3档,这两支队伍的进攻能力略显不足,但依靠卓越的防守能力进行了弥补。中国队也是一支防守实力相对较强的队伍,进攻能力处于第5档,防守能力处于第4档,整体实力处于第4档。2022世界男排锦标赛高水平强队技战术特征为:扣球进攻位置多样化;发球攻击性强;拦网技术全面、配合默契、得分能力强。

广义Kloosterman和及它的四次均值

为了研究对任意素数模p的一类广义Kloosterman和的四次均值,利用初等与解析方法、Gauss和以及三角和的转换性质引入了当素数p≡1 mod 4时该均值的计算问题,并将该类均值转化为特征和的简易形式。从计算结果上对均值的估计具有充分性,从计算方法上对广义Kloosterman和各种形式的四次均值研究具有重要的参考价值。此外,这也为指数和均值计算问题提供了一种新的转化思路与方法,必将对有关问题的进一步探索起到推动作用。

中国城市经济韧性的水平、耦合协调度与空间分布特征

中国经济的强韧性是防范风险的最有力支撑。以全国282个城市为研究样本,采用熵权法与加权秩和比法测算中国城市经济韧性水平,在此基础上利用耦合协调模型、空间自相关模型研究中国城市经济韧性三大子系统的耦合协调度,分析其空间分布的整体特征。研究发现:2011—2019年,中国城市经济韧性整体处在中等水平且呈现缓慢上升趋势,同时区域差异较大;中国城市经济韧性总体处于中级协调阶段,但各地区三大子系统耦合协调度及其增长情况有所不同;中国城市经济韧性的耦合协调度在空间分布上具有正相关性,且呈现显著的空间集聚特征和方向性。由此建议采取措施扎实推进城市经济韧性及城市经济韧性耦合协调度的全方位提升,提高区域经济的整体发展水平。

辽宁省农村三产融合综合评价研究

农村一二三产融合是实现乡村振兴和农业农村现代化的重要手段,有利于农村经济的高质量发展.辽宁省农村一二三产融合在空间上分布不均衡,运用熵权法和秩和比综合评价法研究农村三产融合综合水平,对于辽宁省三产融合高质量发展具有理论与现实意义.首先分析了辽宁省2012—2021年农村三产融合水平的时序变化,然后以2021年为例对辽宁省14地市农村三产融合水平的空间差异进行研究.结果表明:从时间特征来看,辽宁省2012—2021年农村一二三产融合综合水平总体呈上升趋势,受2016年中国经济呈现的放缓态势的影响,2016年融合水平出现明显下降;从空间特征来看,2021年辽宁省农村一二三产融合综合水平各地存在空间差异,其中大连排名第一,沈阳次之,抚顺、营口、辽阳排名靠后,前后存在较大差距.采用障碍度模型计算障碍因子,各地应立足自身优势,弥补不足,关注生产效率和产业链延伸的同时更要注重社会效益和绿色可持续发展,推进辽宁农村三产业融合整体发展.

n 的多项式为系数的幂级数和函数注记

研究了以n的多项式为系数的幂级数的和函数的求解问题,给出了这类幂级数和函数的一种求解方法,并得到了其和函数的通用计算公式,通过实例验证了公式的正确性.文中还得到了两个关于组合数的等式.

基于秩和比分档法的护理质量综合评价与影响因素分析模型

目的建立基于秩和比分档法的护理质量综合评价与影响因素分析模型。方法应用基于秩和比分档法分析某三甲医院2018年24个科室11个反映护理质量的合格率评价指标观测值,对24个科室的护理质量进行客观评价,将计算得到的列秩和比进行分档分析,找出影响该院护理质量的因素。结果将该医院护理质量分为5个等级,4个科室属于“差”等级,9个“较差”等级,7个“中等”等级,2个“较好”等级,2个“好”等级。从护理质量的影响因素看,危重护理合格率、病区管理合格率、一级护理合格率、基础护理合格率为高影响程度指标,静疗护理合格率、文件书写合格率为中影响程度指标。结论应用基于秩和比分档法建立的护理质量综合评价与影响因素分析模型简明易懂,原理自明。

第32届东京奥运会高水平女子排球比赛攻防能力等级评价研究

以2020年东京奥运会女子排球赛12支队伍为研究对象,运用文献资料法、录像分析法和数理统计法等研究方法,对各国女排攻防指标进行等级评价,分析中国队与世界强队的攻防能力,提出建议.结果显示:美国队、巴西队和塞尔维亚队的进攻能力最强,进攻WRSR值均在B级,中国队位居C级;防守能力最强的当数防守WRSR值在B级的美国、巴西、塞尔维亚、俄罗斯和土耳其队,中国队在防守上逊色于其他强队,防守WRSR值处于D级;攻防能力最突出的是巴西队,攻防WRSR值最高,排名第二的则是美国队.12支队伍进攻、防守和攻防WRSR值与比赛名次均呈显著相关,具有统计意义(P值均<0.01).东京奥运会女子排球赛各队共分为5档,攻防能力属于第1档水平的队伍包括美国、巴西、塞尔维亚、俄罗斯,这些队伍代表当今世界女子排坛的最高水平.东京奥运会高水平队伍技战术特征为:扣球进攻位置多样化;发球攻击性强;全面的拦网、默契的配合和极强的得分能力;二传到位率较高.

基于加权密切值法的山东省健康管理服务评价研究

目的:以山东省三级综合医院为切入点,研究目前健康管理服务实施现状,探索其中存在的问题,为出台有关政策措施、提升健康管理服务能力提供依据。方法:在山东各地市随机抽取25家设有健康管理中心或体检中心的三级综合医院,对其健康管理服务现状进行问卷调查;采用加权密切值法和秩和比法两种方法对三级综合医院健康管理服务能力进行评价分档,并根据不同分档医院的健康管理服务能力绘制雷达图,探索薄弱环节。结果:(1)综合评价分档排序中2家医院处于优档,13家医院为中档,3家医院为差档;分别约占11.11%、72.22%、16.67%。(2)同一地市不同三级综合医院健康管理服务能力差异较大。(3)通过“雷达图”直观反映,三档中差档在投入、过程、产出、效果指标方面均与其他两档具有明显差异。结论:政府应加强顶层设计,提升区域内健康管理服务标准化建设;激励三级综合医院发挥骨干带头作用,与医联体各成员单位多项联动,合理构建全域健康管理服务新体系。

突发公共卫生事件下各省医疗物资供给与医疗服务综合效率评价--基于DEA-RSR模型

文章对2020年新冠疫情下我国31个省份医院服务效率进行综合评价,并进行防疫前后综合效率对比,以帮助各省医疗系统提高弹性,在后疫情时代有效应对突发公共卫生事件。从提高不良输出DMU识别能力的角度,将“数据包络分析法(DEA)”和“秩和比综合比较法(RSR)”相结合,利用DEA和反向DEA模型分别从乐观和悲观的角度计算综合效率,在此基础上采用RSR法进行排序、分档。各省医院综合效率划分为四个等级,其中山东、四川、广东3个省份位于第四等级,青海和西藏位于第一等级;青海和西藏的医院在防疫期间的综合实力还有待加强,部分地区医疗资源出现挤兑,各省应调整医疗资源分配、扩大医疗服务功能。

基于TOPSIS法和秩和比法模糊联合的三级公立医院外科绩效评价研究

目的基于三级公立医院绩效考核相关指标对某三级甲等公立医院2024年第一季度外科医疗质量和运营效率进行回顾性分析,为医院手术科室发展提供建议。方法利用加权TOPSIS法、秩和比(ranksumratio,RSR)法以及二者模糊联合的方法对某三级甲等公立医院外科绩效水平进行综合评价。结果2024年第一季度综合评价A12、A13、A6排名前三位,A3、A22、A1排名后三位,大部分科室居于中档,评价结果总体上与评价医院的科室发展情况相同,反映科室的绩效水平存在差异。结论某三级甲等公立医院外科整体绩效水平有待提高,“功能定位”对外科绩效结果影响较大。绩效水平提升应聚焦技术创新与效率优化,强化各要素重视程度。

基于熵权TOPSIS法与秩和比法的高校附属医院科技成果转化评价研究

目的评价安徽省某医科大学12家附属医院科技成果转化工作,为进一步优化高校附属医院科技成果转化提供建议。方法根据所收集的数据使用熵权法为评价指标体系赋权,采用TOPSIS法与秩和比法模糊联合进行综合评价。结果评价指标中权重排名前3位的是以自行实施方式转化的到账总金额(4.801%),以与他人合作实施方式转化获得收益的到账总金额(4.801%),与所属高校共建研发机构、转移机构、转化服务平台数量(4.779%)。模糊联合结果中前3名医院分别为A、C、G,后3名分别为K、H、E。医院之间差异明显,直属附属医院与非直属附属医院存在差异。结论高校附属医院应探索一条具有自身特色的科技成果转化的发展道路,从实际出发作转化;将成果转化融入学科建设,深化拓展科研优势;构建转化意识提升体系,以意识提升带动行动;高校牵头医工融合,搭建医产学研新生态。

Ecoregional height-diameter models for Scots pine in Turkiye

Ecoregion-based height-diameter models were developed in the present study for Scots pine(Pinus sylves-tris L.)stands in Turkiye and included several ecological factors derived from a pre-existing ecoregional classification system.The data were obtained from 2831 sample trees in 292 sample plots.Ten generalized height–diameter models were developed,and the best model(HD10)was selected according to statistical criteria.Then,nonlinear mixed-effects modeling was applied to the best model.The R2 for the generalized height‒diameter model(Richards function)modified by Sharma and Parton is 0.951,and the final model included number of trees,dominant height,and diameter at breast height,with a random parameter associated with each ecoregion attached to the inverse of the mean basal area.The full model predictions using the nonlinear mixed-effects model and the reduced model(HD10)predictions were compared using the nonlinear sum of extra squares test,which revealed significant differences between ecore-gions;ecoregion-based height–diameter models were thus found to be suitable to use.In addition,using these models in appropriate ecoregions was very important for achieving reliable predictions with low prediction errors.