Local and regional flood frequency analysis based on hierarchical Bayesian model in Dongting Lake Basin,China

This study developed a hierarchical Bayesian(HB)model for local and regional flood frequency analysis in the Dongting Lake Basin,in China.The annual maximum daily flows from 15 streamflow-gauged sites in the study area were analyzed with the HB model.The generalized extreme value(GEV)distribution was selected as the extreme flood distribution,and the GEV distribution location and scale parameters were spatially modeled through a regression approach with the drainage area as a covariate.The Markov chain Monte Carlo(MCMC)method with Gibbs sampling was employed to calculate the posterior distribution in the HB model.The results showed that the proposed HB model provided satisfactory Bayesian credible intervals for flood quantiles,while the traditional delta method could not provide reliable uncertainty estimations for large flood quantiles,due to the fact that the lower confidence bounds tended to decrease as the return periods increased.Furthermore,the HB model for regional analysis allowed for a reduction in the value of some restrictive assumptions in the traditional index flood method,such as the homogeneity region assumption and the scale invariance assumption.The HB model can also provide an uncertainty band of flood quantile prediction at a poorly gauged or ungauged site,but the index flood method with L-moments does not demonstrate this uncertainty directly.Therefore,the HB model is an effective method of implementing the flexible local and regional frequency analysis scheme,and of quantifying the associated predictive uncertainty.

A multidimensional and hierarchical model of library mobile service quality

Purpose:Based on the understanding of the characteristics of mobile services(m-services)provided by libraries,we attempt to develop a multidimensional and hierarchical model and a specifically designed measurement scale for the assessment of libraries' m-service quality.Design/methodology/approach:The research has been conducted sequentially in two stages.At the first stage,a multidimensional and hierarchical model of library m-service quality and a measurement scale are developed through literature review and focus group interviews.At the second stage the model is tested using partial disaggregation technique for an analysis of the data collected from over 400 library users in 3 Chinese universities.Findings:The proposed model is shown to fit the data well.The empirical analysis provides strong support for the model,which includes 4 dimensions(service environment,service interaction,information control and service effect) and 12 corresponding sub-dimensions.Research limitations:The sample size needs to be enlarged and the user types need to be expanded to make the sample more representative.Practical implications:The study provides a conceptual framework and measurement tool that can help library managers understand the users' needs in the context of mobile network environment,and boost their libraries' competitiveness by carrying out better services to meet the user demands.Originality/value:The proposed model and measurement scale specifically designed for the assessment of libraries' m-service quality fully reflect the hierarchical structure of libraries' m-service quality.In addition,by using partial disaggregation technique for model testing,we believe our research can serve as a practical reference to those engaged in the development and examination of a multidimensional and hierarchical model.

Safety Risk Assessment of Overturning Construction of Towering Structure Based on Cloud Matter–Element Coupled Model

Rapid urbanization has led to a surge in the number of towering structures,and overturning is widely used because it can better accommodate the construction of shaped structures such as variable sections.The complexity of the construction process makes the construction risk have certain randomness,so this paper proposes a cloudbased coupled matter-element model to address the ambiguity and randomness in the safety risk assessment of overturning construction of towering structures.In the pretended model,the digital eigenvalues of the cloud model are used to replace the eigenvalues in the matter–element basic element,and calculate the cloud correlation of the risk assessment metrics through the correlation algorithm of the cloud model to build the computational model.Meanwhile,the improved hierarchical analysis method based on the cloud model is used to determine the weight of the index.The comprehensive evaluation scores of the evaluation event are then obtained through the weighted average method,and the safety risk level is determined accordingly.Through empirical analysis,(1)the improved hierarchical analysis method based on the cloud model can incorporate the data of multiple decisionmakers into the calculation formula to determine theweights,which makes the assessment resultsmore credible;(2)the evaluation results of the cloud-basedmatter-element coupledmodelmethod are basically consistent with those of the other two commonly used methods,and the confidence factor is less than 0.05,indicating that the cloudbased physical element coupled model method is reasonable and practical for towering structure overturning;(3)the cloud-based coupled element model method,which confirms the reliability of risk level by performing Spearman correlation on comprehensive assessment scores,can provide more comprehensive information of instances compared with other methods,and more comprehensively reflects the fuzzy uncertainty relationship between assessment indexes,which makes the assessment results more realistic,scientific and reliable.

基于层次分解、主成分分析和高斯混合模型的火成岩岩性识别——以惠州26洼古潜山为例

火成岩油气成藏规律复杂,受到火山运动、强构造运动以及风化剥蚀等叠加影响,火成岩的化学成分和结构构造复杂多样,非均质性极强,采用常规岩性识别方法难以一次性将所有岩性准确识别。借鉴层次分解思路,以惠州26洼古潜山为例,提出了一种火成岩岩性测井识别分类方法:综合考虑火成岩地质分类原则和测井响应特征来确定岩性识别层级,基于这种层次性的分类原则,在每一层次定量优选岩性识别敏感参数,建立研究区岩性识别优选层级;在明确岩性识别优选层级的基础上,逐级逐次使用主成分分析(PCA)和高斯混合模型(GMM)对岩性进行判别并确定其计算函数,建立分级优选岩性识别模型,最终达到整体岩性区分的目的。研究结果表明,研究区辉绿岩和闪长岩识别正确率分别为87.31%和84.32%,未分级未优选辉绿岩和闪长岩识别正确率为60.45%和54.88%,分级未优选其岩性识别正确率为69.61%和67.04%,有效提高了研究区的复杂岩性识别精度。该方法的提出对提高火成岩岩性识别精度提供了一种思路,也为研究区古潜山火成岩岩性精确识别提供了参考依据。

北京市与深圳市儿童分级诊疗相关政策对比分析

背景为了解决儿童“看病难”“看病贵”的医疗困境,我国推行了分级诊疗制度。目前国内对儿童分级诊疗相关政策分析的系统研究献见报道。目的作为分级诊疗第一批试点城市,北京市和深圳市社区卫生服务机构(以下简称社区卫生机构)儿童接诊情况差异较大,本研究通过分析两地儿童分级诊疗相关政策,探索政策对社区卫生机构接诊儿童的影响。方法根据研究小组制定的分级诊疗政策研究框架(社区首诊制、双向转诊、医联体、薪酬激励、儿科培训、宣传、农村医疗可及性),在北京市政府、北京市卫生健康委员会、深圳市政府在线、深圳市卫生健康委员会官方网站检索儿童分级诊疗相关政策文件。筛选符合纳入、排除标准的政策,比较两市纳入政策的数量与内容,分析异同点。结果从6953篇政策文件中筛选出35篇符合分级诊疗政策研究框架的政策文件,其中北京市27篇、深圳市8篇。在医联体、薪酬激励、儿科培训方面,两市都有相关政策。在差异性方面北京市在分级诊疗的宣传和农村医疗可及性方面有相关政策,深圳市在社区首诊制和双向转诊制有相关政策。结论通过落实社区首诊制或加大医保支付比例差距方法促进儿童基层首诊、完善双向转诊指征、完善医联体、薪酬激励和儿科培训相关分级诊疗政策可能对改善社区卫生机构接诊儿童现况有重要意义。

突发公共卫生事件下捐赠医疗物资的应急配送研究

在重大公共卫生事件发生后,如何保证捐赠的应急医疗物资能够合理、快速配送到各救援点,成为抢险救灾工作的重要前提。在考虑突发公共卫生事件下应急医疗物资配送“多供应端、多需求端”特征的基础上,以最早应急开始时间为上层目标,以配送成本最小为下层目标,建立了一个双层目标的应急医疗物资配送规划模型,利用分层序列法对该模型进行求解。结合武汉市在新冠疫情下接收捐赠应急医疗物资的配送方案进行算例分析,验证该模型和算法的有效性。

护理研究生科研伦理素养评价指标体系的构建

目的构建护理研究生科研伦理素养评价指标体系,为客观评价护理研究生的科研伦理素养提供工具。方法以素质冰山模型为理论基础,基于文献回顾和小组讨论拟订护理研究生科研伦理素养评价指标体系初稿,应用德尔菲法和层次分析法确定最终评价指标体系和权重。结果2轮函询专家积极系数分别为100%和85.0%,专家权威系数为0.900、0.921,肯德尔和谐系数为0.134、0.189(均P<0.05)。最终形成的护理研究生科研伦理素养评价指标体系,包括2个一级指标(外显科研伦理素养、内隐科研伦理素养)、5个二级指标(科研伦理知识、科研伦理技能、科研伦理能力、科研伦理态度、科研伦理价值观)、31个三级指标。结论构建的护理研究生科研伦理素养评价指标体系科学合理,可作为护理研究生科研伦理素养的评价工具。

基于量子蚁群算法的配电网故障区段快速定位技术

分布式电源并入配电网已成为新型电力系统重要特征之一,分布式电源的接入与发电的不确定性使配电网潮流复杂多变,对配电网故障快速定位提出更高的技术要求.然而,现有智能优化算法在解决配电网故障区段定位问题时会出现收敛速度慢、易陷入局部最优等问题.针对这些挑战与问题,提出一种基于量子蚁群算法(QACA)的配电网故障区段快速定位技术.首先,根据状态逼近思想和最小故障集理论构建配电网故障定位的数学模型;其次,针对馈线终端单元上传信息缺失情况提出信息自修正方法,并提出分级定位模型来缩短定位时间;然后,提出3种改进技术对QACA进行针对性改进,改进量子旋转门更新机制,以函数控制形式动态调整旋转角大小,同时引入精英策略加快算法收敛速度.最后,在关键参数确定后验证了改进技术、信息自修正法、分级定位模型的有效性.将所提算法与7种不同算法进行对比,结果表明:改进的QACA可有效完成故障区段定位,具有良好的收敛速度、准确率以及容错性能.

基于SSA-RF的SAR图像变化检测方法

为了提高合成孔径雷达(Synthetic Aperture Radar, SAR)图像变化检测精度,提出一种基于麻雀搜索算法优化随机森林(Sparrow Search Algorithm-Random Forest, SSA-RF)的SAR图像变化检测方法。该方法首先通过对数比值法得到两时相SAR图像的差异图,然后在差异图预处理后进行层次模糊C均值(Fuzzy C-means, FCM)聚类预检测,生成有效标签。最后,利用标签训练随机森林二次检测模型,并采用麻雀搜索算法对随机森林进行参数优化构建性能稳定的分类器,得到差异图变化类与不变化类的分类结果,从而实现SAR图像的变化检测。实验结果表明,该方法较好地保留了变化区域信息,有效提高了SAR图像的变化检测精度。

电动汽车充电站选址的多层次模糊综合评估方法

为了提升电动汽车充电站选址投建的准确性和合理性,提出了一种多层次模糊综合评估方法。首先,划定选址地所覆盖的目标服务区域,引入区域内POI数据,结合聚类算法和模糊综合评分对区块潜在充电需求等级进行划分。然后,计算目标区域内的单位平方公里直流充电枪数量和目标区域内的单枪日均充电量,确定区域充电桩供应等级和当前的充电热力等级。最后,建立多层次模糊评估模型,确定供需两个层面的数据指标的权重,并通过实例验证模型能够有效量化充电站选址的适用性。

Two-Level Hierarchical PCG Methods for the Quadratic FEM Discretizations of 2D Concrete Aggregate Models

The concrete aggregate model is considered as a type of weakly discontinuous problem consisting of three phases:aggregates which randomly distributed in different shapes,cement paste and internal transition zone(ITZ).Because of different shapes of aggregate and thin ITZs,a huge number of elements are often used in the finite element(FEM)analysis.In order to ensure the accuracy of the numerical solutions near the interfaces,we need to use higher-order elements.The widely used FEM softwares such as ANSYS and ABAQUS all provide the option of quadratic elements.However,they have much higher computational complexity than the linear elements.The corresponding coefficient matrix of the system of equations is a highly ill-conditioned matrix due to the large difference between three phase materials,and the convergence rate of the commonly used solving methods will deteriorate.In this paper,two types of simple and efficient preconditioners are proposed for the system of equations of the concrete aggregate models on unstructured triangle meshes by using the resulting hierarchical structure and the properties of the diagonal block matrices.The main computational cost of these preconditioners is how to efficiently solve the system of equations by using linear elements,and thus we can provide some efficient and robust solvers by calling the existing geometric-based algebraic multigrid(GAMG)methods.Since the hierarchical basis functions are used,we need not present those algebraic criterions to judge the relationships between the unknown variables and the geometric node types,and the grid transfer operators are also trivial.This makes it easy to find the linear element matrix derived directly from the fine level matrix,and thus the overall efficiency is greatly improved.The numerical results have verified the efficiency of the resulting preconditioned conjugate gradient(PCG)methods which are applied to the solution of several typical aggregate models.

Modeling of Economic Processes, Instability and Chaos

We consider a mathematical model describing the dynamics of the three components of the economic activity of enterprises—production, management and resource consumption. For the analysis of the dynamics, the methods and criteria formulated by the authors earlier were used;new results of a practical nature were obtained;in particular, the calculation of the spectrum of small perturbations of the system depending on the input resource and system parameters is given. It is shown that the calculated values of the criteria of instability and chaos are fully consistent with the calculation of the spectrum, indicated the stability intervals of the system, as well as areas of instability and chaos.

基于AHM赋权联合TOPSIS法的康艾注射液利用合理性评价

目的:建立医院患者使用康艾注射液的药物利用合理性评价标准,通过属性层次模型(AHM)赋权联合逼近理想解排序(TOPSIS)法对康艾注射液的使用情况进行分析,为促进合理用药提供参考。方法:制定康艾注射液药物利用评价标准,采用AHM赋权联合TOPSIS法对2021年使用康艾注射液患者的用药合理性进行评价。结果:共抽取210份病历,其中相对接近度最高为100%,最低为57.4%。相对接近度≥90%的病历2份(0.95%),相对接近度80%~90%的病历91份(43.33%),相对接近度70%~80%的病历94份(44.76%),相对接近度60%~70%的病历22份(10.48%),相对接近度<60%的病历1份(0.48%)。康艾注射液在适应证、用法用量等方面存在不合理使用情况。结论:笔者所在医院应用康艾注射液总体较为合理,但尚需加强用药宣教与管理,进一步规范康艾注射液的临床应用。

面向耦合系统的交替方向滚动时域电压分层协同优化控制

我国北方地区普遍存在由风、光等新能源场站与传统同步机组构成并经外送通道功率送出的耦合系统,其新能源单元并网点、场站并网点及耦合系统功率外送并网点均需满足各自的电压安全标准,给电压安全控制带来了严峻挑战。面向耦合系统电压调控问题,该文结合耦合系统单元-场站-系统的物理层级特征,确定了系统层-场站层的电压分层协同控制结构,在各层级内兼顾运行网损优化和电压控制要求,协调各类无功控制资源,建立综合模型预测控制(MPC)和交替方向乘子法(ADMM)的网损优化与电压校正双模式自适应切换的滚动时域控制策略,实现耦合系统的分布式协同电压控制。在修改后的IEEE-14节点耦合系统和大连某区域耦合系统进行仿真,结果表明了该控制策略的有效性和适用性。

海洋中心城市的综合辐射力强化研究——以上海、深圳为例

作为中国沿海一线中心城市,上海和深圳拥有优越的临海区位、现代立体交通网络、成熟的产业经济体系。作为长江三角洲、珠江三角洲区域发达的特大中心城市,上海、深圳提出构建“全球海洋中心城市”的发展规划方案。运用层次分析法构建城市辐射力评价指标体系,与国内7个同样提出构建“全球海洋中心城市”的广州、天津、大连、宁波、舟山、厦门和青岛等沿海中心城市进行辐射力对比,并运用改进的引力模型计算分析辐射力最大的上海、深圳两个中心城市对各自区域内各城市的经济联系强度,再基于两个城市的发展问题,提出优化建议及政策措施。

基于AHP-FCE的黑龙江省农业农村现代化评价

党的二十大提出,把农业农村优先发展作为现代化建设的一项重大原则,没有农业农村现代化,就没有整个国家现代化。为了更好地评价黑龙江省农业农村现代化水平,建立了黑龙江省农业农村现代化水平评价指标体系,构建了层次分析法—模糊综合分析评价模型(AHP-FCE),并将其应用于对黑龙江省农业农村现代化水平评价中,根据评价结果并结合黑龙江省农业农村现代化发展过程中存在的问题提出政策建议。

基于改进层次分析与综合评价方法的装配式建筑成熟度模型研究

文中通过查阅相关文献,阐述了装配式建筑、改进层次分析、综合评级方法等基本理论,对评价指标体系、模型构建的基本方法进行了探究,并以此为基础,建立了装配式建筑评价指标体系以及指标评价模型,最终对装配式建筑在绿色发展方面的成熟度进行了有效判断。

基于层级多尺度方法的TSV晶圆翘曲预测模型研究

随着电子封装技术的发展,以晶圆级封装为代表的先进封装技术对集成密度、封装尺寸,及其制造和服役可靠性提出了更高的要求.TSV晶圆封装结构具有典型的结构多尺度特征,这对有限元模型的建立带来很大挑战.为此,本文提出了一种层级多尺度方法,并验证了所提方法的有效性.围绕上述研究内容,首先,阐明了层级多尺度方法的原理和计算流程;其次采用层级多尺度方法建立了不同TSV晶圆封装工艺下的有限元模型,模拟研究了TSV转接板工艺制程中晶圆的翘曲演化,并与实验结果相对比;最后,研究了分区数量对层级多尺度方法精度的影响.研究结果表明,计算规模相当情况下,随着分区数量的增加,计算误差明显降低.与实验结果的对比表明,该方法有相对较高的晶圆翘曲预测精度.此外,本文发展的层级多尺度方法具有一定的可移植性,可以应用到其它同类具有多尺度特征的封装结构可靠性分析中,为解决大规模晶圆级封装翘曲预测问题提供了一种新的解决思略.