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Journal of Mountain Science 2023年第5期20卷 1249-1265页

作者： wanG Kai ZHANG Shao-jie xie wan-li GUAN Hui School of Architecture and Civil Engineering Zhongyuan University of TechnologyZhengzhou 450007China Department of Geology State Key Laboratory of Continental DynamicsNorthwest UniversityXi′an 710069China Key Laboratory of Mountain Hazards and Earth Surface Process Institute of Mountain Hazards and EnvironmentChinese Academy of SciencesChengdu 610041China

Slope units is an effective mapping unit for rainfall landslides prediction at regional *** present,slope units extracted by hydrology and morphological method report very different morphological feature and *** order to investigate the effect of morphological difference on the prediction performance,this paper presents a general landslide probability analysis model for slope *** Carlo method was used to describe the spatial uncertainties of soil mechanical parameters within slope units,and random search technique was performed to obtain the minimum safety factor;transient hydrological processes simulation was used to provide key hydrological parameters required by the model,thereby achieving landslide prediction driven by quantitative precipitation estimation and forecasting *** prediction performance of conventional slope units(CSUs)and homogeneous slope units(HSUs)were analyzed in three case studies from Fengjie County,*** results indicate that the mean missing alarm rate of CSUs and HSUs are 31.4% and 10.6%,*** Operating Characteristics(ROC)analysis also reveals that HSUs is capable of improving the overall prediction performance,and may be used further for rainfall-induced landslide prediction at regional scale.

关键词： Slope unit Boundaries Slope gradient Landslide prediction

Collapse behavior and microstructural evolution of loess soils from the Loess Plateau of China

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Journal of Mountain Science 2018年第8期15卷 1642-1657页

作者： xie wan-li li Ping ZHANG Mao-sheng CHENG Tian-e wanG Yong State Key Laboratory of Continental Dynamics Northwest University Department of Geology Northwest University Key Laboratory for Geo-hazard in Loess Area Ministry of Land and ResourcesXi'an Center of China Geological Survey College of Urban and Environmental Sciences School of Foreign Languages Northwest University

Loess soils are characterized by metastable microstructure, high porosity and water-sensitivity. These soils have always been problematic soils and attracted attention from researchers all over the world. In the present study, three loess soils extracted at various depths from the Loess Plateau of China, i.e. Malan(Q_3), upper lishi(Q_2~2) and lower lishi(Q_2~1) loess soils, were studied. Single oedometer-collapse tests were performed on intact loess specimens to investigate the collapse behavior of three loess soils. The microstructure and chemical composition of each loess before and after collapse test were characterized using scanning electron microscopy(i.e. SEM) and energy dispersive spectroscopy(i.e. EDS) techniques. The microstructural evolution due to wetting collapse was interpreted qualitatively and quantitatively in terms of the pore morphology properties. The results suggest that:(1) the collapse potential of each loess may rise again after a round of rise and drop, which could be failure of the new-developed stable structure under quite high vertical pressure. It implies that loess may collapse even if it has collapsed.(2) Q_3, Q_2~2 and Q_2~1 loess have different types of microstructure, namely, granule, aggregate and matrix type of microstructure, respectively.(3) The microstructural evolution due to loading and wetting is observed from a granule type to an aggregate type and finally to a matrix type of structure. The variations in distributions of pore morphology properties indicate that collapse leads to a transformation of large-sized pores into small-sized pores, re-orientation and remolding of soil pores due to particle rearrangement.(4) A porous structure is essential for loess collapse; however, the non-water-stability of bonding agents promotes the occurrence of collapse under the coupling effect of loading and wetting.

关键词： Loess Collapse Microstructure Scanning electron microscopy Image processing Pore morphology properties

Influence of temperature on swelling deformation characteristic of compacted GMZ bentonite-sand mixtures

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Journal of Central South University 2018年第11期25卷 2819-2830页

作者： CUI Su-li DU Yan-feng wanG Xue-pan HUANG Sen xie wan-li State Key Laboratory of Continental Dynamics Northwest UniversityXi’an 710069China

Laboratory swelling deformation tests were carried out on compacted GMZ bentonite and bentonite-sand mixtures with 30%and 50%sand contents at 20,40,60,80 and 90°C with infiltration of distilled *** of temperature,initial dry density,and quartz sand content on the swelling deformation characteristic of compacted bentonite specimens was *** indicate that the swelling deformation process is accelerated,and the maximum swelling strain increases with the increase in temperature,while the maximum swelling strain tends to be stable with increasing *** the meantime,the temperature effects depend on both of the sand content and the initial dry density of the specimens,the increases of the maximum swelling strain induced by increasing temperature,are enlarged by increasing sand content or initial dry *** of quartz sand to bentonite not only influences the integrality of bentonite specimen,but also increase the microfissuring in area on quartz sand,which are advantageous to the heat transfer,leading to the increase of swelling deformation capacity of the *** increased dry density relatively increases the bentonite content,so the swelling property is ***,no change on mineral composition of bentonite was observed when temperature was changed from 20 to 90°C.

关键词： GMZ bentonite swelling strain temperature initial dry density sand content

聚乙烯燃气管道DS-AHP-GRA安全评价程序及应用

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压力容器 2018年第9期35卷 43-49,29页

作者：谢丽婉福建省锅炉压力容器检验研究院福建福州350008

随着西气东输项目及石油天然气工程的不断开展,越来越多的聚乙烯燃气管道投入使用。针对聚乙烯燃气管道安全评价中遇到的评价信息不完整且评价属性值由语言值、模糊数或空白值组成的混合型问题,提出基于DS-AHP-GRA理论的聚乙烯燃气管道... 详细信息

随着西气东输项目及石油天然气工程的不断开展,越来越多的聚乙烯燃气管道投入使用。针对聚乙烯燃气管道安全评价中遇到的评价信息不完整且评价属性值由语言值、模糊数或空白值组成的混合型问题,提出基于DS-AHP-GRA理论的聚乙烯燃气管道直觉模糊安全评价方法;并开发了聚乙烯燃气管道DS-AHP-GRA安全评价程序,主体界面采用Visual Basic实现,封装MATLAB软件进行求解。该程序的开发为信息不完整的聚乙烯燃气管道DS-AHP-GRA安全评价提供了一个有效的快速计算工具。

关键词：聚乙烯燃气管道安全评价信息不完整 Visual Basic

Ultrasound for diagnosing new difficult laryngoscopy indicator: a prospective, self-controlled, assessor blinded, observational study

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Chinese Medical Journal 2019年第17期132卷 2066-2072页

作者： Lei wang Yan-Kun Feng liu Hong wan-li xie Shi-Qiang Chen Ping Yin Qing-Ping Wu Department of Anesthesiology Union Hospital Tongji Medical College Huazhong University of Science and Technology Wuhan Hubei 430022 China Department of Anesthesiology Wuhan No.1 Hospital Wuhan Hubei 430022 China Department of Ultrasound Union Hospital Tongji Medical College Huazhong University of Science and Technology Wuhan Hubei 430022 China Department of Epidemiology and Health Statistics School of Public Health Tongji Medical College Huazhong University of Science and Technology Wuhan Hubei 430030 China

Background: Unpredictable difficult laryngoscopy (DL) remains a challenge for anesthesiologists, especially when difficult ventilation occurs during standard laryngoscopy. Accurate airway assessment should always be performed, but the common airway assessment methods only perform superficial screening. Thus, the deep laryngopharyngeal anatomy may not be evaluated. Ultrasound-based airway assessment has been recently proposed as a useful, simple, and non-invasive bedside tool as an adjunct to clinical methods, which may facilitate identification of DL. The present study aimed to determine the correlation between ultrasound-measured indicators and DL. Methods: Patients undergoing elective surgery under general anesthesia with tracheal intubation were enrolled. Ultrasonic airway assessments were performed before anesthesia induction. Ultrasound diagnostic indicators included the thickness and width of the base of the tongue, the angle between the epiglottis and glottis, the length of the thyrohyoid membrane, and the thickness of the lateral pharyngeal wall. A score of ≥3 in the Modified Cormack-Lehane Scoring System was used as a standard of DL and was also applied to divide patients into DL and non-DL groups. The area under the receiver operating characteristic (ROC) curve was used to evaluate the diagnostic ability of various diagnostic indicators. Results: A total of 499 patients were enrolled into non-DL and DL groups comprising 452 (452/499, 90.6%) and 47 (47/499, 9.4%) patients, respectively. One ultrasonic diagnoses indicator correlated with DL, namely, the angle between the epiglottis and glottis. When the angle between the epiglottis and glottis was 50°, the area under the ROC curve was maximum (0.902), and the best sensitivity (81%) and specificity (89%) were achieved. Conclusions: Airway ultrasounds should be considered to identify DL. The ultrasonic angle measured between the epiglottis and glottis is highly associated with DL, which may occur when the angl

关键词： Ultrasonography Laryngoscopy Airway management

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我国上市公司发行公司债融资效率研究

特区经济 2011年第3期 110-111页

作者：谢婉丽南京工业大学江苏南京210009

运用DEA评价方法中的C2R模型,选取2008年和2009年54家发行公司债的上市公司为样本,对我国上市公司发行公司债融资效率进行评价,研究结果发现仅17家公司的公司债发行效率相对有效,总体则处于相对低效状态。进而提出了提高其公司债融资效... 详细信息

运用DEA评价方法中的C2R模型,选取2008年和2009年54家发行公司债的上市公司为样本,对我国上市公司发行公司债融资效率进行评价,研究结果发现仅17家公司的公司债发行效率相对有效,总体则处于相对低效状态。进而提出了提高其公司债融资效率的对策措施。

关键词：公司债融资效率上市公司 DEA

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钢质燃气管道防腐层检测技术对比分析

质量技术监督研究 2017年第6期 31-35,47页

作者：谢丽婉福建省锅炉压力容器检验研究院福建福州350008

随着管道完整性管理的发展,埋地燃气管道的运营安全问题越来越受到有关部门的重视。为有效避免钢质燃气管道腐蚀及各类事故的发生,选择正确的钢质燃气管道防腐层检测技术对提高管道检测准确性十分必要。文中对Pearson、ACVG和DCVG三种... 详细信息

随着管道完整性管理的发展,埋地燃气管道的运营安全问题越来越受到有关部门的重视。为有效避免钢质燃气管道腐蚀及各类事故的发生,选择正确的钢质燃气管道防腐层检测技术对提高管道检测准确性十分必要。文中对Pearson、ACVG和DCVG三种检测技术的基本原理、优缺点和适用条件进行了对比,并通过现场检测开挖验证了三种方法的准确度和精确度,指出了选择防腐层检测方法的前提条件,为开展钢质燃气管道防腐层检测提供参考。

关键词：钢质燃气管道防腐层检测破损点

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陕北某输油站地面开裂原因分析及对策

西北大学学报（自然科学版） 2010年第6期40卷 1064-1068页

作者：蒋臻蔚谢婉丽长安大学地质工程与测绘学院陕西西安710054 西北大学地质学系/大陆动力学国家重点实验室陕西西安710069

目的针对陕北某输油站的地面裂缝,分析其形成原因,评价场地的稳定性,并提出治理措施。方法采用详细的现场勘察,分析站场的地质环境条件及地面开裂的初步原因,运用有限元强度折减法对站场的稳定性进行计算。结果站场内外发育有连续性较... 详细信息

目的针对陕北某输油站的地面裂缝,分析其形成原因,评价场地的稳定性,并提出治理措施。方法采用详细的现场勘察,分析站场的地质环境条件及地面开裂的初步原因,运用有限元强度折减法对站场的稳定性进行计算。结果站场内外发育有连续性较好的裂缝5条,其产生的原因主要为:由黄土层的披覆构造特点及红黏土层的隔水特性而引起的坡体顺层面蠕动;填土区滑坡而引起的后缘张裂缝;土体不均匀沉降。结论该站场裂缝目前还在继续发展变化,随时有形成地质灾害的可能,因此,应根据情况及早进行相应的治理设计与施工。

关键词：裂缝成因边坡稳定性强度折减法