Evaluation of group effect of pile group under dragload embedded in clay

A simple semi-empirical analysis method for predicting the group effect of pile group under dragload embedded in clay was described assuming an effective influence area around various locations of pile group. Various pile and soil parameters such as the array of pile group, spacing of the piles (S), embedment length to diameter ratio of piles (L/D) and the soil properties such as density (γ), angle of internal friction (φ) and pile-soil interface friction coefficient (μ) were considered in the analysis. Model test for dragload of pile group on viscosity soil layer under surface load consolidation conditions was studied. The variations of dragload of pile, resistance of pile tip and the layered settlement of soil with consolidation time were measured. In order to perform comparative analysis, single pile was tested in the same conditions. The predicted group effect values of pile group under dragload were then compared with model test results carried out as a part of the present investigation and also with the values reported in literatures. The predicted values were found to be in good agreement with the measured values, validating the developed analysis method. The model test results show that negative skin friction of pile shaft will reach 80%-90% of its maximum value, when pile-soil relative displacement reaches 2 mm.

A Computational Investigation of the Group Effect of Pits on the Ultimate Strength of Steel Plates

In this work, we focus on assessing the group effect of localized corrosion on the ultimate strength of the marine structural plates and study the load-deformation behaviors of plates of various slenderness and uniaxial compression.Meanwhile, we investigate different corroded patterns from a single circular pit to 25 circular pits distributed over the plate and carry out hundreds of nonlinear finite element simulations by combining the number, depth, distribution of pits with imperfections and slenderness of plate. The distribution of multiple pits causes scattering of stress concentration on the plate, then the plastic section of plate changes with wider distribution of damage simultaneously. The ultimate strength arises when un-loading zone comprised of the yielding strips and holes extends across the plate. It can be concluded that the corroded condition defined as group effect of pits manipulates the deformation state and the loading capacity of plate at the ultimate strength mode that coincides with the proportion of effective loading area and section in the process of post-buckling. To validate the effect of pits group, we perform the numerical experiments of the post-buckling of steel plates containing pits in a row with different orientation.

Bucket Group Effect of the Composite Multi-bucket Structure

As a novel type of foundation in beach and shallow sea, the bucket structure is especially suitable for complex conditions such as soft clay ground and the worse types of sea environments. In this paper, the bearing capacity of a multi-bucket structure is studied by experiments with a single bucket and four-bucket foundation in a saturated sand layer. Based on the experimental data and numerical analysis results, the bearing capacity behavior and the bucket group effect are compared and analyzed. Furthermore, some influential factors, such as the soil type, the ratio of length to diameter L/D, the ratio of the bucket spacing to the bucket diameter S/D, and the bucket number are introduced and their effects on the multi-bucket structural capacity are investigated. The vertical static capacity adjustment factor is introduced to evaluate the bucket group effects of the multi-bucket foundation.

Stabilizing Buried Interface via Synergistic Effect of Fluorine and Sulfonyl Functional Groups Toward Efficient and Stable Perovskite Solar Cells

The interfacial defects and energy barrier are main reasons for interfacial nonradiative recombination.In addition,poor perovskite crystallization and incomplete conversion of PbI_(2) to perovskite restrict further enhancement of the photovoltaic performance of the devices using sequential deposition.Herein,a buried interface stabilization strategy that relies on the synergy of fluorine(F)and sulfonyl(S=O)functional groups is proposed.A series of potassium salts containing halide and non-halogen anions are employed to modify SnO_(2)/perovskite buried interface.Multiple chemical bonds including hydrogen bond,coordination bond and ionic bond are realized,which strengthens interfacial contact and defect passivation effect.The chemical interaction between modification molecules and perovskite along with SnO_(2) heightens incessantly as the number of S=O and F augments.The chemical interaction strength between modifiers and perovskite as well as SnO_(2) gradually increases with the increase in the number of S=O and F.The defect passivation effect is positively correlated with the chemical interaction strength.The crystallization kinetics is regulated through the compromise between chemical interaction strength and wettability of substrates.Compared with Cl−,all non-halogen anions perform better in crystallization optimization,energy band regulation and defect passivation.The device with potassium bis(fluorosulfonyl)imide achieves a tempting efficiency of 24.17%.

Can environmental sustainability be decoupled from economic growth? Empirical evidence from Eastern Europe using the common correlated effect mean group test

The European Union(EU) and Organisation for Economic Co-operation and Development(OECD) aim to develop long-term policies for their respective member countries. Having observed increasing dangers to the environment posed by rising economic growth, they are seeking pathways to enable policy action on economic growth and environmental sustainability. Given the facts in theoretical and empirical studies, this study assessed the validity of the decoupling hypothesis by investigating asymmetricity in the relationship between environmental sustainability and economic growth in nine Eastern European countries from 1998 to 2017 using the cross-section augmented Dickey-Fuller(CADF) unit root, panel corrected standard error(PCSE), common correlated effect mean group(CCEMG), and Dumitrescu Hurlin causality approaches. Both population growth and drinking water are used as controlled variables. The outcomes establish strong cointegration among all the variables of interest. According to the results of CCEMG test, economic growth exerts short-term environmental degradation but has long-term environmental benefits in Eastern Europe;and population growth and drinking water exert a positive effect on environmental sustainability in both the short-and long-run. The results of Dumitrescu Hurlin causality test indicate that environmental sustainability is unidirectionally affected by economic growth. Based on these outcomes, we suggest the following policies:(1) the EU and OECD should implement member-targeted policies on economic growth and fossil-fuel use towards regulating industrial pollution, water use, and population control;and(2) the EU and OECD member countries should invest in environmental technologies through green research and development(R&D) to transform their dirty industrial processes and ensure productive energy use.

On the grouping effect of the l_(1-2)models

This paper aims to study the mathematical properties of the l vmodels that employ measurement matrices with correlated columns.We first show that the l_(1-2)model satisfies the grouping effect which ensures that coefficients corresponding to highly correlated columns in a measurement matrix have small differences.Then we provide the stability analysis based on the sparse approximation property.When the entries of the vectors have different signs,we show that the grouping effect also holds for the constraint l_(1-2)minimization model which is implicated by the linearized Bregman iteration.

On the Effectiveness of Group Work in English Language Teaching

This is a case research on group work and the aim is to investigate the effectiveness of group work in English teaching in English major of Zhejiang Guangsha College of Applied Construction Technology(ZGC).By carrying out a 15-week experiment on 08 Applied English Class 1 and 2,questionnaires on 08 Business English Class 1-5(213 students),and interviews on 22 teachers of English major,the research results show and prove that group work is often performed in ZGC and group work is quite effective in English teaching.

制造企业数字化能力生成的高管团队影响机制与同群效应

数字化时代,传统制造企业普遍沉浸在缺乏“数字化能力”的焦虑中,企业能否运用数字技术和信息资源产生数字化能力,是推动企业数字化战略落地的关键。对297家制造企业高管成员的调查数据进行实证检验,检验高管团队异质性对制造企业数字化能力的影响,探究同群效应下高管团队异质性、组织惯例更新对制造企业数字化能力生成的作用机制,证实数字化能力是高管团队异质性驱动下制造企业不断修正和创造组织惯例的结果。在这一过程中,行业同群效应强度正向调节制造企业数字化能力的构建,但是地区同群效应强度却与制造企业数字化能力的生成无关。研究认为,制造企业数字化能力构建不是单纯的组织内部惯例更新过程,而是外部群体影响下的复杂决策,数字化不仅是单个企业的转型问题,还是受社会互动影响的群体问题。研究结果为制造企业构建数字化能力提供了理论指导与策略参考。

制度压力与企业绿色技术扩散群体行为研究

加快绿色技术扩散能够最大限度地释放创新活力,为生态文明建设提供有力支撑。使用2005-2021年中国A股上市公司绿色专利引用数据探讨企业绿色技术扩散群体行为的存在性、作用机制及实际影响。研究表明,企业绿色技术扩散过程存在显著的行业群体效应,同行企业绿色技术扩散水平提升会强化目标企业的绿色技术扩散意愿;在不同的技术扩散水平、扩散阶段和技术能力上群体效应存在显著差异。将制度压力分为监管、规范和模仿压力,发现3种压力均会激发企业绿色技术扩散的群体行为,并且3种压力具有替代作用,模仿压力替代监管压力,监管压力又替代规范压力,表明企业绿色技术扩散群体行为主要源于竞争而非监管和规范。进一步将企业绩效分为经济绩效和环境绩效,发现企业绿色技术扩散水平提升会改善其经济绩效与环境绩效,群体效应会强化企业对环境绩效的积极影响,抑制对经济绩效的改善作用,研究结论为促进企业绿色技术扩散提供了理论指导与策略参考。

数字化转型、同群效应与企业风险承担

本文基于数字化浪潮下我国企业风险承担意愿不足的现实背景下,从治理能力提升效应、战略韧性增强效应以及环境不确定性对冲效应三个方面阐释了企业数字化转型影响风险承担水平的作用机理,并从行业和地区两个维度论证了企业数字化转型同群效应现象的存在性及其对企业风险承担水平的外生影响。利用2011—2021年我国A股上市公司面板数据,系统考察了企业数字化转型与企业风险承担之间的关系。研究发现:数字化转型显著提高了企业风险承担水平。作用机制方面,企业数字化转型通过对冲外部环境不确定性、提高企业治理能力以及增强企业战略韧性共同提升了企业风险承担水平。进一步研究发现,我国企业数字化转型行为存在明显的行业同群和地区同群特征且是风险承担水平提升的重要原因,同群效应使得高数字化程度企业群体中存在低风险承担水平企业的比例相对较低。即高数字化与低数字化企业风险承担水平分布呈现了明显的“左截尾”特征。

企业基础研究决策的同群效应及影响因素

以2013-2022年中国沪深A股制造业和信息技术业上市企业为样本,实证检验基础研究的同群效应的存在性、模仿路径及其影响因素。研究发现,企业基础研究决策受行业内其他企业的影响,即存在行业同群效应,其模仿路径呈现出一定的先内后外规律。企业所处的竞争地位越高,既往基础研究经验越丰富,其基础研究决策越容易受到行业同群的影响。相较于非国有企业,国有企业基础研究决策受同群企业影响程度较高。研究进一步发现,企业基础研究决策同群效应对企业创新绩效有正向促进作用。研究发现为更好地理解企业基础研究的外在驱动力,并为鼓励企业开展基础研究与完善中国基础研究政策体系提供思路参考。

公立医院DRG临床路径管控方案探索及效果评价

目的:探索基于DRG的临床路径管理方案,评价其实施效果。方法:选取重庆市医保局本土化DRG分组后的数据进行分析,采用Wilcoxon秩和检验对比评估临床路径效果。结果:实行基于DRG的临床路径管控后,不同分组的患者住院费用有效降低,且差异具有统计学意义;DRG组层面,相比非路径组,RE13、RW19、CB19等路径组住院费用均降低且具有统计学意义;同一DRG组的检查费、药品费、耗材费、治疗费及其他费用均有效降低,且差异均有统计学意义。结论:基于DRG的临床路径管理可以通过有效降低具体病种费用,最终达到控制医疗支出、节约医保基金的目的。

微型木桩的群桩效应研究

木材广泛存在于我国村镇中,其取材加工方便,价格低廉,用作村镇住宅的基础结构,可有效减少村镇住宅的能源消耗,符合绿色建筑理念。本文以微型木桩为研究对象,通过离心机模型试验和有限元数值分析,研究了微型木桩在砂土和粉质黏土土层条件下的群桩承载力和群桩效应系数。结果表明,微型木桩的群桩效应系数η在砂土中大于1,在黏土中小于1,受桩土刚度比的影响较小;桩径减小改变了群桩最优桩间距,砂土中微型木桩η随着桩的距径比Sa/D的增大逐渐增大,在Sa/D=6时出现峰值,常规桩在Sa/D=3时达到最大,微型木桩最优桩间距大于常规桩;黏土中,微型木桩η峰值对应的Sa/D=4小于常规桩η峰值对应的Sa/D=6,微型木桩最优桩间距小于常规桩;微型木桩群桩效应系数随内摩擦角和不排水抗剪强度的增大而减小,随距径比的增大先增加后减小,随桩数的增加而增大。

社会建构、反馈效应与延迟退休年龄政策停滞

党的十八届三中全会以来,我国屡次提出研究和制定“渐进式延迟退休年龄政策”的方针策略,然时至今日,全国性的延迟退休政策尚未出台。以社会建构与政策设计理论为理论基础与分析框架,以1951—2021年54份中央政府文件为样本,考察目标群体的社会建构如何通过反馈效应影响延迟退休年龄政策进程,研究发现:干部和高级专业技术人员被正面建构且因政策受益,产生正反馈,政策长期仅适用于该群体,普通劳动者被正面建构但因政策受损,产生负反馈,以致全国性政策无法出台,政策陷入停滞;而正反馈效应长期积累促使社会建构转向,社会环境因素改变政策认知,进而推动政策进程。因此,政策制定者坚定决心,不断优化政策设计,回应目标群体的社会建构转向;党和中央政府以积极应对人口老龄化战略吸纳延迟退休年龄政策,塑造公众政策认知;地方政府积极开展政策试验,总结经验教训,这些措施都有助于加快政策进程。

效果导向视域下高职学校专业群建设质量评价指标体系构建研究

构建科学合理的评价体系是保证高职学校专业群健康发展的有效举措。高职学校专业群建设应以“投入”“产出”“成效或直接效益”“影响或间接效益”等四方面所形成的“效果链”为逻辑框架,基于企业、政府、学校、教师、学生及家长等群体的需求,探索构建以学生为中心、以效果为导向持续改进的专业群建设质量评价指标体系,推动政校行企协同参与专业群质量评价过程,提升项目建设质量,助力学生成长成才,服务企业创新提质。

某三甲中医医院DRG付费实施效果评价

目的评估按DRG付费对某三甲中医医院单病种住院费用的影响。方法以某三甲中医医院2020年1月—2021年12月心内科DRG病组为FM19(经皮冠状动脉支架植入术)的患者住院信息为研究对象,利用Stata15统计软件、运用中断时间序列模型、双重差分法等评估该病组按DRG付费前后的费用变化趋势。结果按DRGs付费实施后,FM19病组年平均总费用下降了26503.62元(P<0.001),年平均耗材费用下降了23937.32元(P<0.001)。FM19病组整体中医中药费用显著下降(P<0.05)。心绞痛患者的总费用、耗材费和药品费整体呈下降趋势;心肌梗死患者的药品费用减少不明显,总费用和耗材费下降显著。结论某病种开展按DRG付费后控费效果显著,中医中药治疗费用下降明显。三甲中医医院需提早布局,应对和适应付费改革。

在系级教学组织中开展课程组建设的探索

在高校专业课程教学过程中,由于任课教师在教学过程还要承担科研任务,导致不同教师的授课能力存在一定差异,使整体教学效果有待进一步提升。因此,根据新时代全国高等学校本科教育工作会议精神以及《教育部关于深化本科教育教学改革全面提高人才培养质量的意见》,基于系级教学组织层面,提出了采用课程组形式,将讲授相同课程的教师组成一个教学团队,并设立课程组责任教授,建立“传帮带”机制,统一教学方式和内容等,有助于提升高等院校的教学水平及教学效果。

探究小班化教学在“环境化学”课程中的应用

为提高“环境化学”课程的教学效果,在教学过程中实施小班化教学模式。通过灵活多样的教学方式,一方面增强了学生参与知识建构的自觉性,达到了深化学习、培养创新思维、提高综合能力的目的;另一方面,在及时反馈课堂教学效果、充分利用网络教学资源提升教学质量等方面展现出明显的优势。同时,以小班化教学模式为依托加强了教师与学生之间的互动,激发了学生的学习积极性和学习兴趣。“环境化学”课程的小班化教学经验对于环境科学专业其他课程的教学具有很好的借鉴价值。

扩底桩竖向承载特性及群桩效应研究

为探明扩底群桩竖向承载特性,采用扩底桩筏结构,开展单桩(扩径比分别为1.5、2.0、2.5、3.0)和桩筏(扩径比为2)基础静载模型试验,分析其荷载传递规律,并建立桩间距为3.75、4.00、4.50、5.00倍桩直径时扩底桩筏基础有限元模型,研究桩间距对群桩效应影响。结果表明:扩底单桩和扩底桩筏结构荷载沉降曲线均为缓变型;扩底桩极限承载力随扩径比增大而逐渐增大,扩径比2.5~3.0时极限承载力增幅变缓,建议扩底桩扩径比取2.5~3.0;由于桩土共同沉降,桩间土压缩,桩土作用更充分,扩底桩筏基础中心桩侧摩阻力荷载分担比比扩底单桩增大了17.71%;群桩效应系数随桩间距增大而逐渐增大,桩间距为4.5~5.0倍桩直径时群桩效应系数增幅较小,群桩效应较弱,建议扩底桩筏基础桩间距取值不小于4.5倍桩直径。