基于云模型的应急决策方法

针对突发灾害事故应急决策过程中存在的模糊性和随机性问题,提出了一种基于云模型的应急决策方法.首先根据突发灾害事故应急的目标和特点选择决策指标并建立决策指标集;然后基于决策者的语言值及其对应的数域确定决策指标的权重值和评价值,利用逆向云发生器算法生成云模型的数字特征;再利用综合云的思想,运用云运算规则,得到各应急方案的评价云;最后把应急方案的评价云与评价标准云进行相似性比较,综合判断应急方案的评价等级并优选最佳的应急方案.实例研究表明：该方法充分利用了专家的群体信息,实现了应急方案决策中定性语言和定量评价之间的有效转化,结果更为直观、合理,便于改善应急决策的客观性和提高应急管理的效率.     

基于有限云模型的深基坑安全性研究

为降低基坑安全评价指标等级边界信息的随机性和模糊性给评价结果带来的不利影响,构建基于有限区间云理论的基坑安全综合评价模型。依据基坑安全性评价指标分类标准,计算出各评价指标隶属于不同分类等级的云数字特征,然后利用博弈论组合赋权法明确各评价指标的权重,并结合有限正向云发生器,得到评价对象的综合确定度,最后根据最大隶属原则确定基坑安全性等级。将该方法应用于工程实践中,并在评价过程中与传统云模型、可拓法进行对比分析。研究结果表明：运用该方法所获取的基坑安全性评价结果与可拓法评价结果一致,符合工程实际,且克服了传统云模型在处理指标值远离两端云期望值时的弊端,可为基坑安全评价研究提供一种新思路。     

基于云理论的隧道结构健康诊断方法

隧道健康状态诊断过程作为一个模糊系统,具有随机性和模糊性的特点.传统的隧道结构健康诊断方法无法妥善地将系统的模糊性和随机性关联在一起.基于此,针对隧道结构健康状态诊断系统的模糊性和随机性特点,提出了基于云理论的隧道结构健康状态诊断方法.首先,建立反映隧道结构健康状况等级评语集的正态云模型.然后,依据逆向云发生器原理,将隧道结构健康状态指标的监测数据的归一化结果值转化为隶属度云模型.将健康状态指标的重要性语言值转化为权重云,用于表征各健康状态指标的重要程度.最后,运用云理论的计算方法对隧道结构健康状态等级进行诊断,得到健康状态等级诊断结果的云模型.应用云模型的改进方法,对某市地铁2号线盾构隧道结构健康状态进行了诊断,极大提高了诊断结果的可视化和鲁棒性.     

基于变权联系云的采空区稳定性二维评价模型

针对采空区稳定性评价具有模糊性、随机性以及评价指标等级呈有限区间正态分布等问题,考虑评价指标值突变对评价指标权重的影响,提出了基于变权联系云的采空区稳定性二维评价模型。首先选取12个评价指标构建采空区评价指标体系,并通过各指标联系云图反映其实际分布情况;然后利用博弈论和变权理论得到变权权重;最后计算采空区各评价指标对应等级的确定度和采空区的综合确定度,并根据最大隶属度原则确定采空区稳定性等级。为解决指标等级归属不一致的问题,引入模糊熵作为第二维评价系统,以表征采空区稳定性的复杂度。结果表明:变权联系云模型评价结果与实例应用结果一致,验证了该模型的可行性与合理性。     

滨海金矿涌水危险评价及涌水量混沌预测研究

针对海底金矿涌水危险评价过程中的不确定性及随机性问题,选择工程地质及水文地质中涉及的10个重要因素构建评价指标体系,建立起涌水危险评价的云模型。基于评价结果,对危险区域的涌水量时间序列进行相空间重构,通过G-P算法及自相关法获得了重构相空间参数;分析了涌水量变化的相点距离演变规律,建立了涌水安全预警机制。结合混沌相空间重构,建立了涌水量预测的RBF神经网络模型。研究表明：涌水危险性的云模型评价结果准确可靠;相空间重构揭示了系统的混沌特性,最邻近相点演化将涌水量的内在细微变化特征放大,为涌水安全预警机制的建立提供了依据;混沌RBF神经网络能够实现涌水量的短期精确预测,为井下安全开采提供了技术保障。     

基于综合决策云模型的围岩稳定性分级方法研究

地下工程围岩稳定性分析关系到地下工程的安全,围岩的稳定与否直接决定着地下工程的成败,因此开展地下工程围岩稳定性评价具有十分重要的意义。基于云理论,选取岩石单轴饱和抗压强度、完整性系数、岩石基本质量指标、地下水影响修正系数和软弱结构面产状影响系数作为围岩稳定性分级指标,综合运用DEMATEL决策模型和熵权法获取上述指标体系的组合权重,并选取公路隧道工程20组实测数据作为学习样本,建立围岩稳定性分级的综合决策云模型,将其应用于小红石砬子玉石矿5组工程围岩的稳定性分级实例中。结果表明:综合决策云模型判别结果与实际情况相吻合,判别准确率可达80%,且优于K-最邻近算法和随机森林算法的判别结果,说明所建立的综合决策云模型在工程实际中具有一定的应用价值,为围岩稳定性分级提供了新思路。     

基于IAHP-靶心贴近度法的充填管道可靠性评估

为对充填管道可靠性进行科学评估,建立了基于改进层次分析法(IAHP)、靶心贴近度法的综合评估模型。以湖南某矿山为研究对象,选取了充填料浆骨料体积分数等10个指标构建了综合评价指标体系,采用改进层次分析法确定指标权重,通过计算评估对象各等级单指标区间函数和综合贴近度,基于最大隶属度原则,对矿山充填管道可靠性进行风险等级评估,并与未确知测度理论和云模型评估结果进行对比。结果表明,基于IAHP-靶心贴近度法的充填管道可靠性综合评估模型结果合理,具有计算简便、直观可靠、操作性强等优势,为充填管道可靠性评估提供了新思路。     

基于博弈论—云模型的岩体质量评价模型研究

为科学有效评估岩体质量,引入云模型理论,构建了基于博弈论-云模型的地下工程岩体质量综合评价模型。首先,从强度因素、完整性因素和地质因素等3个方面,选取了6个典型性影响因素,构建了岩体质量综合评价指标体系;其次,采用博弈论思想计算综合权重,通过计算单指标隶属度和综合确定度,基于最大隶属度原则,综合判断岩体质量等级;最后,以某金矿为研究背景,选取了4个典型区域岩体,进行相关计算。结果表明,该模型评估结果与实际相符,可以为岩体质量评估工作提供一条可量化的新思路。     

基于层次分析与模糊综合评判的回采方案优选

应用层次分析法与模糊数学原理,建立了某钨矿矿区回采方案的综合评判模型,科学合理地选出了该矿最优回采方案.在优选过程中,综合考虑影响回采方案的各项影响因素,利用层次分析法确定各评价指标的权重,并根据模糊数学原理对备选回采方案进行综合评判,得出各方案的优越度.实例计算结果得出2种方案综合优越度分别为0.791 0和0.748 1,因而确定方案1优于方案2.研究实例结果表明,该综合评判法可以对受多个定量和定性指标影响的决策进行有效的综合权衡分析,可为方案优选提供科学的指导.     

基于相对差异函数的金属矿采空区危险性识别

为了经济合理地治理金属矿采空区,建立了相对差异函数的采空区危险性识别模型。首先建立含14个指标的采空区危险性识别指标体系,并采用相对差异函数确定评价指标对评价级别的相对隶属度和熵权法、层次分析法（AHP）确定评价指标的组合权重;然后计算采空区危险性对评价级别的综合相对隶属度和级别特征值;最后根据级别特征值的平均值确定采空区的危险性级别。将该模型运用于某锡矿山8个采空区的危险性评价识别中,确定了各采空区的危险性级别,识别结果与未确知测度理论法识别结果相一致,符合现场实际。研究结果表明：该模型可通过自身参数的4种组合来提高采空区危险性识别结果的可靠性,为采空区危险性识别提供了一种新的方法。     

Large Deformation Finite-Element Analysis of Submarine Landslide Interaction with Embedded Pipelines

Submarine landslides represent one of the most significant geohazards on the continental slope in respect of the risk they pose to infrastructure such as deep water pipelines. A numerical approach, based on the finite-element method but using remeshing, was established in this paper to simulate large flow deformation of debris from a landslide and to quantify the loads and displacements imposed on pipelines embedded in the seabed. A simple two-dimensional elastic perfectly plastic soil model with plane strain conditions was employed in this analysis. The pipeline was restrained by a set of springs so that the load on the pipeline built up to a stable value, representing the limiting load at which the debris flowed over the pipeline. A parametric study was undertaken by varying the pipeline embedment and the relative strengths of the debris and seabed. The analysis results show that the various combinations of soil strength and embedment depth lead to different debris-pipeline movement patterns and consequently lead to rather different magnitudes of the loads imposed on pipelines. The pipeline is subjected to the largest load (an equivalent pressure of 11.5 times debris strength) from the landslide when it rests on the weakest seabed. The pressure is proportional to the debris material strength but varies inversely with the seabed strength for partially embedded pipelines. For all strength combinations, there is a critical embedment depth beyond which the force on the pipeline reduces to a very small magnitude.     

炉卷轧机生产X70管线钢

介绍了安阳钢铁股份有限公司采用150 t转炉、连铸、炉卷轧机生产线生产高强度高韧性X70管线钢的情况,包括成分体系设计和轧制工艺。通过合理运用微合金化技术和炉卷卷取轧制工艺开发的管线钢,机械性能优良,合格率达99.3%,满足长距离油气输送管道要求。     

基于IPSO-GRU深度学习算法的海底管道缺陷尺寸磁记忆定量反演模型

针对海底管道缺陷磁记忆定量反演的难题,提出一种基于改进粒子群优化的门控循环神经网络模型,即IPSO-GRU模型。以两端焊有盲板的X52管道作为实验材料,其上预制有不同直径、深度的缺陷,采用TSC-5M-32磁记忆检测仪,外接11-6W非接触探头,进行水下磁记忆检测试验,提取不同缺陷尺寸的磁记忆信号特征值。考虑到磁记忆信号特征值随缺陷尺寸呈复杂的非线性变化,引入门控循环神经网络,利用其双门结构能够记忆缺陷处的信号特征,非线性回归拟合能力强的特点,构建海底管道缺陷定量反演模型,进一步考虑到模型超参数选择的随机性,采用改进粒子群算法进行超参数寻优。验证结果表明:该模型对缺陷深度反演平均精度达96%;对缺陷直径反演平均精度达93%,为海底管道缺陷的磁记忆定量化识别与反演提供了新的思路和方法。      

降雨和地震条件下浅层黄土滑坡三维稳定性评价

以兰州市大沙沟流域浅层黄土滑坡为研究对象,整合降雨渗透模型到黄土斜坡三维确定性模型,评价不同降雨和地震耦合效应下浅层黄土滑坡稳定性,并用混淆矩阵法和受试者工作特征曲线法（ROC）评价稳定性评价预测的结果。研究结果发现,耦合降雨入渗和地震的三维确定性模型,对流域尺度浅层黄土滑坡稳定性评价具有较好效果,能作为降雨和地震诱发黄土滑坡灾害评价和早期预警的工具,对加强不同尺度极端事件下黄土滑坡灾害时空灾害评价和预测具有重要参考价值。      

Crack Growth Modeling and Life Prediction of Pipeline Steels Exposed to Near-Neutral pH Environments: Stage II Crack Growth and Overall Life Prediction

This investigation was initiated to provide governing equations for crack initiation, crack growth, and service life prediction of pipeline steels in near-neutral pH (NNpH) environments. This investigation develops a predictive model considering loading interactions occurring during oil and gas pipeline operation with underload-type variable pressure fluctuations. This method has predicted lifetimes comparable to the actual service lives found in the field. This is in sharp contrast with the predictions made by existing methods that are either conservative or inconsistent with the field observations. It has been demonstrated that large slash loads (R-ratio is 0.05), often seen during gas pipeline operation, are a major life-limiting factor and should be avoided where possible. Oil pipelines have shorter lifetime because of their more frequent pressure fluctuations and larger amplitude load cycles. The accuracy of prediction can be improved if pressure data with appropriate sampling intervals are used. The sampling interval error is much larger in the prediction of oil pipelines than gas pipelines because of their different compressibility but is minimized if the pressure sampling rate for the data is at or less than one minute.     

Automatic girth welding and performance evaluation of the joints of hot-induction-bend and line pipes with different wall thickness

During the process of laying long-distance oil and gas transmission pipelines,the hot-induction-bend method is extensively used when the direction has to be changed.By considering the pipeline's ongoing processing and loading states during service,the pipeline that is generally used exhibits thicker walls than those that are observed in the line pipe.As such,during pipeline construction,hot-induction-bend and line pipes with different wall thickness are girth-welded.The chemical composition of hot-induction-bend and line pipes differs,with the carbon content being particularly higher in the hot-induction-bend pipe;it also depicts a higher carbon equivalent,which makes it possible to modify the girth of the pipe.In this study,using Baosteel's standard X70M UOE hotinduction-bend and line pipes,solid-wire automatic gas-metal-arc girth welding was performed and the performance of the girth-welded joint was evaluated.Furthermore,the weldability of the pipeline girth and the microstructure of the girth-welded joint were analyzed.The results reveal that Baosteel's standard UOE hot-induction-bend and line pipes exhibit good girth weldability,and their technical quality can be guaranteed in case of consumer fieldconstruction applications.