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静压桩在成层地基中挤土效应的可视化研究

河南城建学院学报 2024年第2期33卷 20-26页

作者：施静怡吴能森刘强福建农林大学交通与土木工程学院福建福州350108 新疆理工学院机电工程学院新疆阿克苏843100

为探究静压桩在成层地基中的挤土效应及其与均质地基的差异,利用透明土结合粒子图像测速技术(PIV),对成层土和均质土地基进行静压桩贯入可视化模型试验。对土体位移矢量图、位移等值线图以及软硬土层交界面的位移特征进行分析,结果显示... 详细信息

为探究静压桩在成层地基中的挤土效应及其与均质地基的差异,利用透明土结合粒子图像测速技术(PIV),对成层土和均质土地基进行静压桩贯入可视化模型试验。对土体位移矢量图、位移等值线图以及软硬土层交界面的位移特征进行分析,结果显示:桩侧土位移及地表隆起,静压桩在黏土地基中的影响范围大于砂土,但在桩侧3倍桩径范围内,砂土地基的挤土效应大于黏土地基;对比均质黏土地基,“上黏下砂”地基的桩端挤土效应减弱,而桩侧的水平位移增大,桩侧2倍桩径以内地表隆起值增大,桩侧2倍桩径以外地表隆起值减小;对比均质砂土地基,“上砂下黏”地基的桩端挤土效应增强,桩侧3倍桩径以内的水平位移、地表隆起值减小,但地表隆起影响范围扩大到4倍桩径以外;在成层地基的土层交界面,上下层土体的位移大小不同,尤其是桩侧附近的位移差值较大。

关键词：静压桩成层地基挤土效应可视化模型试验粒子图像测速技术

药物临床试验管理课程实践教学改革的探索与思考

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浙江医学教育 2024年第4期23卷 198-203页

作者：周倩施菁陈婷王欣杭州医学院药学院医院药学教研室杭州311399 杭州医学院药学院杭州311399 杭州医学院药学院药事管理教研室杭州311399

本文基于杭州医学院药学人才培养目标,探索与思考实践教学在药物临床试验管理课程中的改革成效。针对药物临床试验管理课程教学中存在的缺乏实践教学、考核形式单一等问题,采用理论结合实践的教学方式进行改革。通过建设实践教学基地,... 详细信息

本文基于杭州医学院药学人才培养目标,探索与思考实践教学在药物临床试验管理课程中的改革成效。针对药物临床试验管理课程教学中存在的缺乏实践教学、考核形式单一等问题,采用理论结合实践的教学方式进行改革。通过建设实践教学基地,组织实施实践教学,融入思想政治教育,注重实践教学和理论知识的多样化考核,药物临床试验管理课程实践教学改革取得了积极成效。学生满意度调查和学生访谈结果表明,实践教学能够提高学生的参与度和积极性,帮助学生明确学习目标和职业规划,锻炼学生的综合能力,得到了学生的普遍认可。因此,积极开展实践教学有利于提高学生对药物临床试验管理课程以及相应岗位的深入理解,提高了药物临床试验管理课程的授课质量。

关键词：药物临床试验管理实践教学课程改革课程思政思考

黄河流域下游煤矿区耕地时空演变及驱动力分析:以山东济宁为例

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首都师范大学学报（自然科学版） 2024年第5期45卷 30-39页

作者：史静曹倩倩周丙锋首都师范大学资源环境与旅游学院北京100048

山东省济宁市地处黄河流域下游煤矿区,面临着耕地资源严重破坏等问题。本文基于济宁市1980―2020年土地利用数据和社会经济数据,借助土地利用转移矩阵和主成分分析方法,探究济宁市各县市区耕地时空变化特征和驱动机制,并采用灰色预测模... 详细信息

山东省济宁市地处黄河流域下游煤矿区,面临着耕地资源严重破坏等问题。本文基于济宁市1980―2020年土地利用数据和社会经济数据,借助土地利用转移矩阵和主成分分析方法,探究济宁市各县市区耕地时空变化特征和驱动机制,并采用灰色预测模型对未来耕地面积进行预测。结果表明:(1)济宁市耕地具有“西多东少”的典型特征,且耕地面积不断减少,工业、煤矿和交通建设用地面积不断增加;(2)1980―2020年济宁市耕地主要转出至建设用地、草地和水域,其中1980―1990年县市区耕地变化动态较高,2000―2010年耕地面积变化程度较小;(3)经济因素是引起耕地变化的主要驱动因素,且煤炭开采占国内生产总值比例和第二产业产值占总产值比例为影响耕地面积的主要驱动因子;(4)预测显示,2020―2035年耕地面积将继续呈减少趋势。因此,耕地保护政策的制定应该充分考虑经济因素,因地施策,推进资源节约型城市建设。

关键词：耕地时空演变驱动机制灰色预测济宁市

Health risk assessment of dietary exposure to polycyclic aromatic hydrocarbons in Taiyuan, China

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Journal of Environmental Sciences 2014年第2期26卷 432-439页

作者： jing Nie jing shi Xiaoli Duan Beibei Wang Nan Huang Xiuge Zhao Chinese Research Academy of Environmental Sciences State Key Lab of Environmental Criteria and Risk Assessment Soil and Water Science College of Resources and Environmental Sciences China Agricultural University Department of Safety Engineering China Institute of Industrial Relations

Sixteen polycyclic aromatic hydrocarbons （PAHs） were determined in 24 duplicate-diet samples from people in Taiyuan during summer and winter in 2009. Dietary intake of PAHs for 2862 participants was subsequently estimated by a survey in Taiyuan. Results from these 24 samples were compared with a raw food study in Taiyuan in 2008. Three main sources of dietary PAHs are vegetables, wheat flour and fruits, the sum of which contributes 75.95% of PAHs in dietary food. Compared to the estimated value in raw food, much more B[a]Peq （benzo[a]pyrene equivalents） were detected in food samples collected in the duplicate-diet study in Taiyuan （60.75 ng/day）. The cooking process may introduce more B[a]Peq into food, and the relative contribution of 16 PAHs in the diet would be changed during the cooking procedure.

关键词： dietary exposure food health risk assessment polycyclic aromatic hydrocarbons (PAHs) benzo[a]pyrene

Star-factorization of the Complete Bipartite Multigraphs

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Acta Mathematicae Applicatae Sinica 2023年第2期39卷 239-248页

作者： jing shi Jian WANG Bei-liang DU School of Science Nantong UniversityNantong 226007China Department of Mathematics Suzhou UniversitySuzhou 215006China Mathematics Teaching and Research Office Nantong Vocational CollegeNantong 226007China

LetλK_(m,n)be a complete bipartite multigraph with two partite sets having m and n vertices,respectively.A K_(p,q)-factorization ofλK_(m,n)is a set of K_(p,q)-factors ofλK_(m,n)which partition the set of edges ofλK_(m,n).Whenλ=1,Martin,in[Complete bipartite factorizations by complete bipartite graphs,Discrete Math.,167/168(1997),461–480],gave simple necessary conditions for such a factorization to exist,and conjectured those conditions are always *** this paper,we will study the K_(p,q)-factorization ofλK_(m,n)for p=1,to show that the necessary conditions for such a factorization are always sufficient whenever related parameters are sufficiently large.

关键词： complete bipartite multigraph star factorization

Discrimination of rice panicles by hyperspectral reflectance data based on principal component analysis and support vector classification

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2010年第1期11卷 71-78页

作者： Zhan-yu LIU jing-jing shi Li-wen ZHANG jing-feng HUANG Institute of Agricultural Remote Sensing and Information System Application Zhejiang University Hangzhou 310029 China Ministry of Education Key Laboratory of Environmental Remediation and Ecological Health Zhejiang University Hangzhon 310029 China Key Laboratory of Agricultural Remote Sensing and lnformation System in Zhejiang Province Hangzhou 310029 China

Detection of crop health conditions plays an important role in making control strategies of crop disease and insect damage and gaining high-quality production at late growth stages. In this study, hyperspectral reflectance of rice panicles was measured at the visible and near-infrared regions. The panicles were divided into three groups according to health conditions： healthy panicles, empty panicles caused by Nilaparvata lugens St^l, and panicles infected with Ustilaginoidea virens. Low order derivative spectra, namely, the first and second orders, were obtained using different techniques. Principal component analysis （PCA） was performed to obtain the principal component spectra （PCS） of the foregoing derivative and raw spectra to reduce the reflectance spectral dimension. Support vector classification （SVC） was employed to discriminate the healthy, empty, and infected panicles, with the front three PCS as the in- dependent variables. The overall accuracy and kappa coefficient were used to assess the classification accuracy of SVC. The overall accuracies of SVC with PCS derived from the raw, first, and second reflectance spectra for the testing dataset were 96.55%, 99.14%, and 96.55%, and the kappa coefficients were 94.81%, 98.71%, and 94.82%, respectively. Our results demonstrated that it is feasible to use visible and near-infrared spectroscopy to discriminate health conditions of rice panicles.

关键词： Rice panicle Principal component analysis (PCA) Support vector classification (SVC) Hyperspectra reflectance Derivative spectra

Design for aircraft engine multi-objective controllers with switching characteristics

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Chinese Journal of Aeronautics 2014年第5期27卷 1097-1110页

作者： Liu Xiaofeng shi jing Qi Yiwen Yuan Ye School of Transportation Science and Engineering Beihang University School of Automation Shenyang Aerospace University School of Energy and Power Engineering Beihang University

The aircraft engine multi-loop control system is described and the switching control theory is introduced to solve the regulating and protecting control problems in this paper. The aircraft engine multi-loop control system is firstly described and the control problems are formulated. Secondly, the theory of the smooth switching control is devoted and a new extended scheme for the smooth switching of a switched control system is introduced. Then, for the key technologies of aero-engines switching control, a design algorithm is presented which can determine which candidate controller should be put in feedback with the plant to achieve a desired performance and the procedure to design the aircraft engine multi-loop control system is detailed. The switching performance objectives and the switching scheme are given and a family of PID controllers and compensators is designed. The simulation shows that using the switching control design method can not only improve the dynamic performance of the aircraft engine control system and reduce the switching times, but also guarantee the stability in some peculiar occasions.

关键词： Aircraft engine Compensatory controller Min/Max switching Multi-objectives control Smooth switching Switching scheme

氢吗啡酮静脉自控镇痛对瘢痕妊娠患者辅助行子宫动脉栓塞术后镇痛的有效性和安全性

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介入放射学杂志 2024年第3期33卷 240-244页

作者：石静谢军袁玉山李琳娜陈颍安徽省阜阳市人民医院介入放射科安徽阜阳236000 安徽省阜阳市人民医院岳家湖院区急诊外科安徽阜阳236000

目的评价氢吗啡酮静脉自控镇痛(pcatient-controlled intravenous analgesia,PCIA)对瘢痕妊娠患者辅助行子宫动脉栓塞术(uterine artery embolization,UAE)术后镇痛的有效性和安全性。方法选取2021年1月至2022年9月在阜阳市人民医院瘢... 详细信息

目的评价氢吗啡酮静脉自控镇痛(pcatient-controlled intravenous analgesia,PCIA)对瘢痕妊娠患者辅助行子宫动脉栓塞术(uterine artery embolization,UAE)术后镇痛的有效性和安全性。方法选取2021年1月至2022年9月在阜阳市人民医院瘢痕妊娠行UAE辅助治疗的患者116例。依据UAE术后PCIA药物不同,随机分为观察组、对照组,每组为58例。分别于手术开始前10 min静注氢吗啡酮2 mg(观察组)和舒芬太尼2μg/kg(对照组),并连接患者自控静脉镇痛泵。观察组:氢吗啡酮10 mg+氟比洛芬酯100 mg+0.9%氯化钠注射液100 mL配置至镇痛泵中;对照组:舒芬太尼2μg/kg+氟比洛芬酯100 mg+0.9%氯化钠注射液100 mL配置至镇痛泵中。记录两组患者UAE术后0.5、4、8、12、24、48 h视觉模拟量表(visual analogue scale,VAS)评分、布鲁格曼舒适度量表(Bruggrmann comfort scale,BCS)评分,术后48 h内镇痛泵按压次数、镇痛药物用量、不良反应及术后并发症发生率。结果观察组术后0.5 h VAS评分与对照组比较,差异无统计学意义(P>0.05),而术后4、8、12、24、48 h VAS评分明显低于对照组,差异有统计学意义(均P0.05),而两组患者不良反应发生率比较差异有统计学差异(P<0.05)。结论氢吗啡酮和舒芬太尼PCIA有助于缓解瘢痕妊娠子宫动脉栓塞术术后疼痛,但氢吗啡酮对比舒芬太尼可明显降低术后VAS评分、提高术后BCS评分,术后48 h内镇痛泵按压次数及镇痛药物用量减少、不良反应发生率较低,有一定的推广价值。

关键词：氢吗啡酮瘢痕妊娠子宫动脉栓塞术静脉自控镇痛镇痛

Physical modelling of particle transport phenomenon and vibration behavior of converter with bottom powder injection

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Journal of Iron and Steel Research International 2022年第11期29卷 1771-1788页

作者： jing-shi Zhang Wen-tao Lou Miao-yong Zhu Key Laboratory for Ecological Metallurgy of Multimetallic Mineral(Ministry of Education) Northeastern UniversityShenyang 110819LiaoningChina School of Metallurgy Northeastern UniversityShenyang 110819LiaoningChina

A cold model of top-bottom blown converter was set up to study the particle transport phenomenon and vibration performance of converter with bottom powder *** effect of bottom blowing flow rates,tuyere diameters,arrangements,and powder to gas mass ratios on powder distribution and furnace body vibration was *** results show that the bottom injection parameters and modes have significant effects on the particle transport behavior and furnace *** powder dispersion uniformity and furnace vibration increase with the increase in bottom blowing tuyere *** the lower range of bottom blowing flow rates and powder to gas mass ratios,the powder dispersion uniformity is improved with the increase in ***,in the higher range,the excessive furnace vibration leads to reduction in uniformity in powder *** the bottom blowing tuyeres arrange at double arrangement of 0.5R(R refers to the radius of the bottom)distance between tuyere and center of bath bottom,the converter has optimal particle transport behavior and vibration *** vibration law of converter with bottom powder injection was revealed by deducing the empirical formulas of furnace vibration maximum *** vibration intensity is affected by Froude number,powder to gas mass ratio,and tuyere arrangement.

关键词： Converter steelmaking Bottom powder injection Powder dispersion uniformity Furnace vibration Physical modelling