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Investigation of anisotropic strength criteria for layered rock mass

Journal of Rock Mechanics and Geotechnical Engineering 2024年第4期16卷 1289-1304页

作者： Shuling Huang Jinxin Zhang Xiuli Ding Chuanqing Zhang Gang Han Guoqi Yu lulu qu Key Laboratory of Geotechnical Mechanics and Engineering of the Ministry of Water Resources Changjiang River Scientific Research InstituteWuhan430071China State Key Laboratory of Geomechanics and Geotechnical Engineering Institute of Rock and Soil MechanicsChinese Academy of SciencesWuhan430000China University of Chinese Academy of Sciences Beijing100049China

Layered rock mass is a type of engineering rock mass with sound mechanical anisotropy,which is generally unfavorable to the stability of underground *** investigate the strength anisotropy of layered rock,the Mohr-Coulomb and Hoek-Brown criteria are introduced to establish the two transverse isotropic strength criteria based on Jaeger's single weak plane theory and maximum axial strain theory,and parameter determination ***,the sensitivity of strength parameters(K 1,K 2,and K 3)that are used to characterize the anisotropy strength of non-sliding failure involved in the strength criteria and confining pressure are *** results demonstrate that strength parameters K 1 and K 2 affect the strength of layered rock samples at all bedding angles except for the bedding angle of 90°and the angle range that can cause the shear sliding failure along the bedding *** strength of samples at any bedding angle decreases with increasing K 1,whereas the opposite is for K *** for bedding angles of 0°and 90°and the bedding angle range that can cause the shear sliding along the bedding plane,K 3 has an impact on the strength of rock samples with other bedding angles that the specimens'strength increases with increase of K *** addition,the strength of the rock sample increases as confining pressure ***,the uniaxial and triaxial tests of chlorite schist samples were carried out to verify and evaluate the strength criteria proposed in the *** shows that the predicted strength is in good agreement with the experimental *** test the applicability of the strength criterion,the strength data of several types of rock in the literature are ***,a comparison is made between the fitting effects of the two strength criteria and other available criteria for layered rocks.

关键词： Layered rock Strength anisotropy Strength criterion Experimental verification

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晚期胃肠道肿瘤患者化疗中全程营养支持护理的应用效果分析

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中外医疗 2024年第22期43卷 162-165页

作者：张丽瞿露露施仪婷南通市通州区中医院肿瘤内科江苏南通226300

目的探究行化疗治疗的晚期胃肠肿瘤患者护理中在常规护理基础上加入全程营养支持护理的应用价值。方法方便选取2020年1月—2023年1月于南通市通州区中医院接受化疗的82例晚期胃肠道肿瘤患者为研究对象,根据不同护理方法分为对照组(n=41... 详细信息

目的探究行化疗治疗的晚期胃肠肿瘤患者护理中在常规护理基础上加入全程营养支持护理的应用价值。方法方便选取2020年1月—2023年1月于南通市通州区中医院接受化疗的82例晚期胃肠道肿瘤患者为研究对象,根据不同护理方法分为对照组(n=41)、研究组(n=41),对照组行常规护理,研究组在对照组基础上行全程营养支持护理。比较两组患者的营养状态、生活质量及护理满意度。结果干预90 d后,两组患者的营养状态评分均低于干预前,且研究组营养状态评分为(3.24±1.01)分,低于对照组(3.89±1.13)分,差异有统计学意义(t=2.746,P<0.05);干预90 d后,研究组的生活质量评分高于对照组,差异有统计学意义(P<0.05)。研究组护理总满意度高于对照组,差异有统计学意义(P<0.05)。结论全程营养支持护理应用于接受化疗的晚期胃肠道肿瘤患者护理中,可改善营养状态、生活质量,同时促使患者护理满意度提升。

关键词：晚期胃肠道肿瘤全程营养支持护理营养状态生活质量护理满意度

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Dynamic evolution and the mechanism of modern gully agriculture regional function in the Loess Plateau

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Journal of Geographical Sciences 2022年第11期32卷 2229-2250页

作者： qu lulu LI Yurui WANG Yongsheng DONG Shijie WEN Qi School of Public Policy and Administration Chongqing UniversityChongqing 400044China Institute of Geographic Sciences and Natural Resources Research CASBeijing 100101China Key Laboratory of Regional Sustainable Development Modeling CASBeijing 100101China School of Geography and Planning Ningxia UniversityYinchuan 750021China

The agricultural regional type and function are the key theoretical issues in agricultural geography *** agriculture in the Loess Plateau is a new regional type of agricultural system with the coupling development of the modern gully human-earth *** study of its functional changes is of great practical significance for food security,rural revitalization and sustainable development of regional agriculture in the region of *** paper analyses the multifunctional change of gully agriculture in the Loess Plateau and its dynamic mechanism by using large-scale remote sensing data,topographic relief amplitude model,and spatial econometric model to understand internal implications for evolution differentiation at the basin *** results show that:(1)The spatial concentration of production and supply function of agricultural products(APF)in the gully of the Loess Plateau gully is high,while the ecological conservation and maintenance function(ECF),employment and social security function(ESF),cultural heritage and leisure function(CRF)are relatively *** four functions’spatial distribution has revealed an apparent regularity.(2)APF has been significantly enhanced,which is mainly distributed in point clusters and strips in the farming and pastoral areas in northern Shaanxi to the Yanhe river *** high-value areas of ESF are clustered around the urbanized metropolitan circles and urban-rural staggered areas along the Great *** is concentrated in areas with significant natural endowments and excellent ecological *** is significantly higher in the municipal districts and the surrounding regional central cities.(3)There are noticeable differences in the gully agriculture regional function(GARF)evolution process due to the geographical environment and socio-economic development *** this regard,natural factors have tremendously affected APF,ESF,and ECF,while socio-economic factors greatly differ in the four functions

关键词： dynamic mechanism functional evolution gully human-earth system Loess Plateau modern gully agriculture transformation and development

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A BiLSTM cardinality estimator in complex database systems based on attention mechanism

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CAAI Transactions on Intelligence Technology 2022年第3期7卷 537-546页

作者： Qiang Zhou Guoping Yang Haiquan Song Jin Guo Yadong Zhang Shengjie Wei lulu qu Louis Alberto Gutierrez Shaojie Qiao School of Information Science and Technology Southwest Jiaotong UniversityChengduChina School of Software Engineering Chengdu University of Information TechnologyChengduChina School of Energy Power and Mechanical Engineering North China Electric Power UniversityBaodingChina Digital Media Art Key Laboratory of Sichuan ProvinceSichuan Conservatory of MusicChengduChina Department of Computer Science Rensselaer Polytechnic InstituteNew YorkNew YorkUSA

An excellent cardinality estimation can make the query optimiser produce a good execution *** there are some studies on cardinality estimation,the prediction results of existing cardinality estimators are inaccurate and the query efficiency cannot be guaranteed as *** particular,they are difficult to accurately obtain the complex relationships between multiple tables in complex database *** dealing with complex queries,the existing cardinality estimators cannot achieve good *** this study,a novel cardinality estimator is *** uses the core techniques with the BiLSTM network structure and adds the attention ***,the columns involved in the query statements in the training set are sampled and compressed into ***,the Word2vec model is used to embed the word vectors about the query ***,the BiLSTM network and attention mechanism are employed to deal with word *** proposed model takes into consideration not only the correlation between tables but also the processing of complex *** experiments and the evaluation of BiLSTM-Attention Cardinality Estimator(BACE)on the IMDB datasets are *** results show that the deep learning model can significantly improve the quality of cardinality estimation,which is a vital role in query optimisation for complex databases.

关键词： attention BiLSTM cardinality estimation complex database systems query optimiser Word2vec

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黄土高原沟道农地转换特征及影响机制初探

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农业资源与环境学报 2022年第4期39卷 806-816页

作者：璩路路重庆大学公共管理学院重庆400044

生态建设和土地整治工程驱动黄土高原沟道土地利用及农业生产发生较大变化,为探讨其农地转换特征及影响机制,以延安市地处黄土高原丘陵沟壑区的8个区县为研究区,选取2000—2005、2005—2010、2010—2018年3期24幅Landsat TM/OLI数据,采... 详细信息

生态建设和土地整治工程驱动黄土高原沟道土地利用及农业生产发生较大变化,为探讨其农地转换特征及影响机制,以延安市地处黄土高原丘陵沟壑区的8个区县为研究区,选取2000—2005、2005—2010、2010—2018年3期24幅Landsat TM/OLI数据,采用CART决策树分类方法提取出研究区的沟道农地分布并分析其空间变化,构建时空地理加权回归模型,挖掘延安市沟道人地系统特征,探究其空间要素沟道农地的时空转换及其影响机制。结果表明:近20年延安市沟道农地呈现发散式分布、阶段性扩展且总体波动式收缩趋势,重心整体向北迁移;加入时间序列坐标的时空地理加权回归在沟道农地转换研究中具有较强的适用性,社会经济因素是近20年延安市沟道农地转换的主要驱动力,且影响效应呈现逐年上升态势;延安市沟道农地转换的不同驱动因子系数时空分布各异,人口因子和坡度因子的作用强度始终处于主导地位,地均GDP因子高值分布区在北部和中西部地区,形成“核心边缘”的漏斗状格局,其变化趋向于核心“流动”。黄土高原沟道农地发展变化受多种因素驱动,地区本底差异及不同的行为主体促使沟道农地发展变化趋于不同方向,但根本上均受国家及区域重大发展政策导向的影响。

关键词：沟道农地识别黄土高原时空地理加权回归人地系统科学延安市

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Vegetation Restoration in Response to Climatic and Anthropogenic Changes in the Loess Plateau, China

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Chinese Geographical Science 2020年第1期30卷 89-100页

作者： qu lulu HUANG Yunxin YANG Lingfan LI Yurui Faculty of Geographical Science Beijing Normal UniversityBeijing 100875China Institute of Geographic Sciences and Natural Resources Research Chinese Academy of SciencesBeijing 100101China

A thorough understanding of the vegetation succession in relation to both climatic changes and anthropogenic activities is vital for the formulation of adaptation strategies that address potential ecosystem *** climatic factors such as temperature,precipitation,and solar radiation,as well as anthropogenic factors such as ecological engineering and population migration,will affect the conditions for ***,the relationships among various factors remain unclear and the response of vegetation to climate change and anthropogenic activities in the Loess Plateau of China has not been well *** study investigated the spatio-temporal characteristics and relationships between vegetation coverage and climatic factors in the Loess Plateau for the period of 1985–*** analysis separated the anthropogenic and climatic factors on vegetation succession based on residual *** results showed that the normalized difference vegetation index(NDVI)followed a significant upward trend with annual change rates of 0.15%during 1985–*** trend of human-induced NDVI increase was consistent with the spatial distribution of increasing forest areas in the eastern part of the Loess ***-restoration projects were the main driving factors that promoted vegetation coverage on the Loess ***,these results demonstrated that migrants to cities in the Loess Plateau could relieve ecological pressures and promote vegetation ***,the government should strive to increase population mobility and restore vegetation to sustain this particularly fragile ecological environment.

关键词： vegetation restoration climate change anthropogenic activities Loess Plateau the Grain for Green Project

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丛枝菌根真菌提高植物非生物逆境胁迫适应性研究进展

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草学 2024年第1期 4-9页

作者：屈璐璐郭秀芳贾振宇张跃华杨占坤马怀林刘亚玲内蒙古蒙草生态环境(集团)股份有限公司内蒙古呼和浩特010070 内蒙古蒙草种业科技研究院有限责任公司内蒙古呼和浩特010070

近年来,自然界中低温、干旱等灾害频繁爆发,多种逆境胁迫严重影响了植物的正常生长发育。丛枝菌根真菌(arbuscular mycorrhizal fungi,AMF)是广泛分布在土壤中的一种真菌,可以与植物共生形成庞大的菌丝网络,扩大植物汲取土壤水分的面积... 详细信息

近年来,自然界中低温、干旱等灾害频繁爆发,多种逆境胁迫严重影响了植物的正常生长发育。丛枝菌根真菌(arbuscular mycorrhizal fungi,AMF)是广泛分布在土壤中的一种真菌,可以与植物共生形成庞大的菌丝网络,扩大植物汲取土壤水分的面积,增加对土壤营养元素的吸收,提高宿主植物的产量、质量以及应答逆境胁迫等。本文对AMF提高宿主植物非生物胁迫(温度、干旱、盐碱、重金属)抗性的研究进展进行综述,并对今后的研究方向作出展望。

关键词：丛枝菌根真菌非生物胁迫适应性

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黄土丘陵沟壑区农业生产情景模拟及优化

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地理研究 2023年第6期42卷 1647-1662页

作者：璩路路李裕瑞王介勇重庆大学公共管理学院重庆400044 中国科学院地理科学与资源研究所中国科学院区域可持续发展分析与模拟重点实验室北京100101 中国科学院大学资源与环境学院北京100049

黄土丘陵沟壑区沟道农业是现代人地关系耦合发展的一种地域新类型,深入研究其生产特征及优化途径对于促进区域农业提质增效、推进乡村振兴和黄河流域高质量发展具有重要现实意义。以延安宝塔区作为典型案例,通过建立模糊量化有序加权平... 详细信息

黄土丘陵沟壑区沟道农业是现代人地关系耦合发展的一种地域新类型,深入研究其生产特征及优化途径对于促进区域农业提质增效、推进乡村振兴和黄河流域高质量发展具有重要现实意义。以延安宝塔区作为典型案例,通过建立模糊量化有序加权平均的结构优化模型,模拟分析黄土高原沟道农业生产结构转型特征,研究提出沟道农业优化调控地域模式。研究表明:①设置了维持现状型、经济优先型、可持续导向型和一季改两季型等四种沟道农业生产情景,不同地域类型及其不同发展导向决定着农地利用的多宜性和经营方式的多样性。②不同类型区沟道农业发展演进成因及其机制存在明显差异,不同情景下沟道农业结构演变的特征与优化模式各异,农业规划、政策与技术因素对沟域尺度的沟道农业生产发展分异影响显著。③沟道农业的组织机制和技术创新,亟需着力解决三重关系、推进四种转变、实现四个优化,促进农业生产由广种薄收转向集约高效,农村经济由单一农业转向三产融合,进而实现沟道边坡植被改善、坝地种植结构优化、农业规模经营提高和乡城一体互动发展。

关键词：沟道农业生产情景模拟气候变化优化模式人地系统科学黄土丘陵沟壑区

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Visualization of nasal powder distribution using biomimetic human nasal cavity model

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Acta Pharmaceutica Sinica B 2024年第1期14卷 392-404页

作者： Jiawen Su Yan Liu Hongyu Sun Abid Naeem Huipeng Xu Yue qu Caifen Wang Zeru Li Jianhua Lu lulu Wang Xiaofeng Wang Jie Wu Lixin Sun Jiwen Zhang Zhigang Wang Rui Yang Li Wu Key Laboratory of Modern Preparation of TCM Ministry of EducationJiangxi University of Chinese MedicineNanchang 330004China Key Laboratory of Molecular Pharmacology and Drug Evaluation School of PharmacyMinistry of EducationYantai UniversityYantai 264005China Shanghai Institute of Materia Medica Chinese Academy of SciencesShanghai 201210China Nantong Haimen People’s Hospital Nantong 226199China Yangtze Delta Drug Advanced Research Institute Nantong 226126China Shenyang Pharmaceutical University Shenyang 110016China National Institutes for Food and Drug Control Beijing 100000China Nanjing University of Chinese Medicine Nanjing 210023China

Nasal drug delivery efficiency is highly dependent on the position in which the drug is deposited in the nasal ***,no reliable method is currently available to assess its impact on delivery *** this study,a biomimetic nasal model based on three-dimensional(3D)reconstruction and three-dimensional printing(3DP)technology was developed for visualizing the deposition of drug powders in the nasal *** results showed significant differences in cavity area and volume and powder distribution in the anterior part of the biomimetic nasal model of Chinese males and *** nasal cavity model was modified with dimethicone and validated to be suitable for the deposition *** experimental device produced the most satisfactory results with five spray ***,particle sizes and spray angles were found to significantly affect the experimental device’s performance and alter drug distribution,***,mometasone furoate(MF)nasal spray(NS)distribution patterns were investigated in a goat nasal cavity model and three male goat noses,confirming the in vitro and in vivo *** conclusion,the developed human nasal structure biomimetic device has the potential to be a valuable tool for assessing nasal drug delivery system deposition and distribution.

关键词： Nasal drug deposition Nasal drug distribution Nasal drug delivery Biomimetic nasal model Nasal powder Three-dimensional reconstruction Three-dimensional printing Nasal drug distribution

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城镇化进程中耕地多功能权衡/协同关系演变及其驱动机制

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农业工程学报 2022年第8期38卷 244-254页

作者：李怡方斌李裕瑞璩路路李冬杰南京师范大学地理科学学院南京210023 南京师范大学新型城镇化与土地问题研究中心南京210023 中国科学院区域可持续发展分析与模拟重点实验室北京100101 中国科学院地理科学与资源研究所北京100101 江苏省地理信息资源开发与利用协同创新中心南京210023 重庆大学公共管理学院重庆400044

城镇化进程中中国耕地利用功能变化深刻,探究影响耕地多功能协同与权衡的城镇化因素更是平衡地区经济发展与耕地保护的关键。该研究以淮海经济区为例,选取2000—2018年连续年份时间,从耕地生产、社会和生态三个维度构建评价体系分析耕... 详细信息

城镇化进程中中国耕地利用功能变化深刻,探究影响耕地多功能协同与权衡的城镇化因素更是平衡地区经济发展与耕地保护的关键。该研究以淮海经济区为例,选取2000—2018年连续年份时间,从耕地生产、社会和生态三个维度构建评价体系分析耕地多功能时空特征,利用Spearman秩相关分析揭示耕地多功能间权衡与协同的时空演化,运用调节效应模型定量剖析权衡与协同演化的城镇化驱动机制。结果表明:1)耕地生产功能整体呈持续增长趋势,社会功能整体呈持续下降趋势,生态功能整体呈波动下降趋势。2)耕地生产与社会功能整体呈弱权衡向弱协同转变,且大部分地市内部的两功能权衡关系有所缓解,协同区域逐渐向东部转移。耕地生产与生态功能整体呈权衡增长趋势,但部分地市内部的两功能关系趋向协同发展,主要分布在鲁南和苏北地区。3)耕地生产与社会功能相互关系主要受城乡收入差距、人口城镇化率以及居民消费能力的影响。耕地生产与生态功能相互关系则受居民消费能力的显著影响。同一驱动因子在不同水平下对耕地多功能之间权衡与协同关系的作用程度不同。为此提出促进淮海经济区耕地多功能协同发展的策略建议。

关键词：耕地多功能权衡协同演变驱动机制城镇化淮海经济区

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