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用解析法求解“Philo’s Line” 被引量:2
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作者 郭存娣 《西安工业学院学报》 1992年第2期78-82,共5页
从数学分析入手,运用极值原理,找到了“Philo’s Line”在给定条件下的解析表达式,由此解析表达式作出“Philo’s Line”图形.为在铁路、公路、桥梁等工程设计中,确定过定角内一定点并与角的两边相交,且夹在交点间的线段最短的直线,提... 从数学分析入手,运用极值原理,找到了“Philo’s Line”在给定条件下的解析表达式,由此解析表达式作出“Philo’s Line”图形.为在铁路、公路、桥梁等工程设计中,确定过定角内一定点并与角的两边相交,且夹在交点间的线段最短的直线,提供了切实可行的方法. 展开更多
关键词 直线束 斜率 极值 Philo线 解析法
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Geochemistry of the volcanic rocks from Bioko Island(“Cameroon Hot Line”): Evidence for plume-lithosphere interaction 被引量:2
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作者 Fadimatou Ngounouno Yamgouot Bernard Déruelle +2 位作者 Isaac Bertrand Gbambié Mbowou Ismaila Ngounouno Daniel Demaiffe 《Geoscience Frontiers》 SCIE CAS CSCD 2016年第5期743-757,共15页
Bioko Island(3008 m a.s.l) is located in the presently more active volcanic zone of the Cameroon Line and composed essentially of alkaline basalts and hawaiites, and lesser mugearites. The rocks show microlitic porp... Bioko Island(3008 m a.s.l) is located in the presently more active volcanic zone of the Cameroon Line and composed essentially of alkaline basalts and hawaiites, and lesser mugearites. The rocks show microlitic porphyritic texture with phenocrysts of olivine(83% 〈 Fo 〈 87%) and clinopyroxene in a matrix of plagioclase, clinopyroxene and oxides. Hawaiites and mugearites also include phenocrysts of plagioclase(An62-67Ab35-32Or3-1). Major element variation diagrams show an increase in Si O2, Al2O3, Na2 O and K2 O with increasing Mg O for the studied rock groups. The rocks are characterized by low(^86Sr/^87Sr)i ratios(0.70320e0.70406), high 3Nd(t) values(2.56e4.33) and high(^206Pb/^204Pb)i ratios(20.032e20.035) values.Basalts are enriched in LILE and LREE, and have(Hf/Sm)N= 0.57e1.16. These geochemical signatures are similar to those of the Mount Cameroon rocks, and might be attributed to low degrees of partial melting from a garnet-amphibole-bearing mantle source. The trace elements and isotopic compositions suggest that the parental magma source might have involved HIMU- and EM1-components. 展开更多
关键词 GEOCHEMISTRY HIMU-EM1 Volcanic rocks BIOKO Cameroon Hot line
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Petrology of the Volcanic Rocks from Bioko Island(“Cameroon Hot Line”) 被引量:1
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作者 Fadimatou Ngounouno Yamgouot Bernard Deruelle +1 位作者 Isaac Bertrand Gambie Mbowou Ismaila Ngounouno 《International Journal of Geosciences》 2015年第3期247-255,共9页
Bioko island (3008 m a.s.l.), is composed of the alkaline basaltic lavas (basalts and hawaiites) with xenoliths. These lavas have a microlitic textureand consisted of euhedral to subhedral phenocrysts?(>1 mm) of ol... Bioko island (3008 m a.s.l.), is composed of the alkaline basaltic lavas (basalts and hawaiites) with xenoliths. These lavas have a microlitic textureand consisted of euhedral to subhedral phenocrysts?(>1 mm) of olivine (0.83 < Mg# < 0.87) and diopside ± Ti-augite. Plagioclase (An62-67Ab35-32Or3-1) phenocrysts are present only in hawaiites. In Harker diagrams, SiO2, Al2O3, Na2O and K2O contents of the lavas increase and Fe2O3, MgO and CaO decrease with increasing differentiation from basalts to hawaiites. The compatible elements Ni, Cr and V decrease strongly in basalts and remain at low levels in hawaiites. Basaltic lavas from Bioko lavas have low Hf contents (4.2 - 9.2 ppm) and consequently higher Hf/Zr ratios (50 - 90) than those (<50) of similar lavas from other volcanoes of the Cameroon Hot Line. Such high ratios are commonly observed in alkaline basaltic lavas associated with carbonatitic and/or nephelinitic magmatism. The Sr and Nd isotopic compositions point to a slightly depleted mantle source. 展开更多
关键词 PETROLOGY GEOCHEMISTRY LAVAS BIOKO Cameroon Hot line
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以“LINE”操控家电的时代——带你了解LG的HomeChat服务
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《数字家庭》 2014年第8期94-97,共4页
Home Chat的理念 通过LG我们了解到,虽然LG已实现了实用化的SmartThinQ这个优秀的智能家电服务,但是LG的目标绝不仅是这样。如果智能家电不能让全世界的人们更加简单地利用起来,而是仅作为一部分核心用户的小众服务,那么将始终无... Home Chat的理念 通过LG我们了解到,虽然LG已实现了实用化的SmartThinQ这个优秀的智能家电服务,但是LG的目标绝不仅是这样。如果智能家电不能让全世界的人们更加简单地利用起来,而是仅作为一部分核心用户的小众服务,那么将始终无法盛行起来。 展开更多
关键词 智能家电 LG 服务 line 操控 HOME CHAT 实用化
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德国Victoria 2014电动自行车新品 新型“eManufaktur”系列配有BOSCH的“Active Line”电机
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作者 江南 《中国自行车》 2013年第12期109-109,共1页
德国Victoria为隶属其旗下的品牌(“Victoria”)注入新的活力,近期向市场全力推出一种取名为“eManufaktur”的新的电动自行车系列。所有6款款式均配有BOSCH“Active Line-驱动系统”。
关键词 BOSCH 电动自行车 line 德国 电机 驱动系统
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德国Bosch强劲推出堪称“2014”名为“Performance Line”和“Active Line”的二大系列电机新品
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作者 海南 《中国自行车》 2013年第11期102-103,共2页
德国Bosch目前强劲推出堪称“2014“、专为电动自行车(标准一电动自行车和大功率一电动自行车)配套的二大系列电机新品:“Active Line(系列)”和”Performance Line(系列)”。在我们这儿,您现在即可看到有关Bosch新型电机的第... 德国Bosch目前强劲推出堪称“2014“、专为电动自行车(标准一电动自行车和大功率一电动自行车)配套的二大系列电机新品:“Active Line(系列)”和”Performance Line(系列)”。在我们这儿,您现在即可看到有关Bosch新型电机的第一手资料、功率指标,以及照片等。德国Bosch专为大功率电动自行车和标准型电动自行车提供强劲之动力。德国施瓦比斯地区的工程师们从这一角度出发,自2010年以来始终全身心地致力于各种新品开发,其经坚持不懈努力,终于如愿以偿,使本企业发展成为当今电动自行车这一领域的领导者。德国Bosch电机”变种“进一步拓展自己在电动自行车市场上所占据的市场份额。 展开更多
关键词 BOSCH line 德国 电机 电动自行车市场 大功率 新品开发 企业发展
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“FUENTE GOLD-LINE”旅游自行车个性凸显强烈
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作者 江国强 《中国自行车》 2008年第9期59-59,共1页
荷兰GAZELLE公司(荷兰自行车行业中颇具知名度的一家自行车生产企业),将其不久前所开发的一种取名为“FUENTEGOLD—LINE”系列的自行车,堪称为“专供骑车旅游(度假)者使用、品质绝对纯正”的多功能旅游式自行车。据介绍,该车不... 荷兰GAZELLE公司(荷兰自行车行业中颇具知名度的一家自行车生产企业),将其不久前所开发的一种取名为“FUENTEGOLD—LINE”系列的自行车,堪称为“专供骑车旅游(度假)者使用、品质绝对纯正”的多功能旅游式自行车。据介绍,该车不仅鞍座(舒适型)的倾角.甚至于连鞍座至车把的间距也可根据需要随意进行无级调节(不需要借助任何辅助工具),个性凸显非常强烈。 展开更多
关键词 自行车行业 line 旅游 个性 生产企业 辅助工具 无级调节 知名度
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Experimental,Numerical,and Analytical Studies on the Bending of Mechanically Lined Pipe 被引量:1
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作者 WEI Wen-bin YUAN Lin +1 位作者 ZHOU Jia-sheng LIU Zheng 《China Ocean Engineering》 SCIE EI CSCD 2024年第2期221-232,共12页
Mechanically lined pipe(MLP)is often used for offshore oil and gas transport because of its low cost and corrosion resistance.During installation and operation,the pipe may undergo severe bending deformation,which cau... Mechanically lined pipe(MLP)is often used for offshore oil and gas transport because of its low cost and corrosion resistance.During installation and operation,the pipe may undergo severe bending deformation,which causes the liner to separate from the outer pipe and buckles,affecting the stability of the whole line.In this paper,the buckling response of MLP subjected to bending is investigated to clarify its bending characteristics by employing both experiments,numerical simulation,as theoretical methods.Two types of MLPs were manufactured with GB 45 carbon steel(SLP)and Al 6061(ALP)used as the outer pipe material,respectively.The hydraulic expansion and bending experiments of small-scale MLPs are conducted.In addition to the ovalized shape of the cross-section for the SLP specimens,the copper liner was found to wrinkle on the compressive side.In contrast,the liner of ALP remains intact without developing any wrinkling and collapse mode.In addition,a dedicated numerical framework and theoretical models were also established.It was found both the manufacturing and bending responses of the MLP can be well reproduced,and the predicted maximum moment and critical curvatures are in good agreement with the experimental results. 展开更多
关键词 lined pipe BENDING nonlinear ring theory BUCKLING PLASTICITY
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N^(6)-腺苷甲基化修饰及其对LINE-1的调控机制
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作者 张傲 岑山 李晓宇 《遗传》 CAS CSCD 北大核心 2024年第3期209-218,共10页
长散布元件-1(long interspersed elements-1,LINE-1)是现今在人类基因组中唯一具有自主转座能力的转座子,其转座会引起细胞基因组结构和功能的改变,是导致多种严重疾病的重要因素。在转座过程中,LINE-1 mRNA是转座中间体的核心,宿主细... 长散布元件-1(long interspersed elements-1,LINE-1)是现今在人类基因组中唯一具有自主转座能力的转座子,其转座会引起细胞基因组结构和功能的改变,是导致多种严重疾病的重要因素。在转座过程中,LINE-1 mRNA是转座中间体的核心,宿主细胞对其进行相关修饰直接影响转座。N^(6)-腺苷甲基化修饰(m^(6)A)是真核细胞RNA上最丰富且动态可逆的表观遗传修饰。目前发现m^(6)A修饰也存在于LINE-1 mRNA上,参与LINE-1整个生命周期的调控,影响其转座和基因组中LINE-1相邻基因的表达,进而影响基因组稳定性、细胞自我更新与分化潜能,在人类发育和疾病中具有重要作用。本文介绍了LINE-1 m^(6)A修饰的位置、功能以及相关机制,并总结了LINE-1的m^(6)A修饰对其转座调控的研究进展,以期为相关疾病发生发展的机制研究和治疗提供新的思路。 展开更多
关键词 m^(6)A修饰 逆转录转座子 line-1 基因组 基因组稳定性
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低压低氧对肠黏膜屏障及LINE-1核酸内切酶变异体GCRG213表达的影响
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作者 张王静怡 张少杰 +4 位作者 陶虹锦 孟繁森 刘静 朱玲玲 王刚石 《解放军医学院学报》 CAS 2024年第3期296-301,F0003,共7页
背景长散在核元件-1(long interspersed nuclear element-1,LINE-1或L1)是目前基因组中唯一活跃的自主反转录转座元件,低压低氧环境可以改变L1的甲基化程度。目的探究低压低氧环境对肠黏膜中L1核酸内切酶(L1 endonuclease,L1-EN)变异体G... 背景长散在核元件-1(long interspersed nuclear element-1,LINE-1或L1)是目前基因组中唯一活跃的自主反转录转座元件,低压低氧环境可以改变L1的甲基化程度。目的探究低压低氧环境对肠黏膜中L1核酸内切酶(L1 endonuclease,L1-EN)变异体GCRG213表达水平及以闭合蛋白(Occludin)和紧密连接蛋白-1(Claudin-1)表达水平为指标的肠黏膜机械屏障功能的影响。方法利用免疫组织化学染色(immunohistochemical staining,IHC)检测人正常小肠、结肠组织及小鼠正常结肠组织的GCRG213表达,观察GCRG213蛋白在正常肠道中的分布规律。将雄性C57BL/6小鼠随机分为实验组和对照组。实验组模拟海拔6000 m环境,饲养7 d构建低压低氧小鼠模型,对照组常压常氧饲养。将人正常结肠上皮细胞NCM-460随机分为常氧组以及低氧24 h、48 h组,常氧组于常氧环境正常培养,低氧组分别于0.3%O2浓度下培养24 h、48 h构建低氧细胞模型。使用qPCR、Western blot技术检测GCRG213、Occludin和Claudin-1在小鼠结肠组织及人NCM-460细胞中表达水平的变化。结果人正常小肠、结肠及小鼠结肠组织IHC结果一致显示,GCRG213表达于肠黏膜柱状上皮细胞胞质中,而在杯状细胞中未见表达。在动物实验中,与常氧组相比,低压低氧组小鼠结肠组织GCRG213在mRNA水平(P<0.05)和蛋白水平(P<0.01)均表达上调;同时,Occludin在蛋白水平表达下调(P<0.05)。在细胞实验中,低氧暴露后NCM-460细胞中GCRG213在mRNA(P<0.001)和蛋白水平(P<0.01)均表达上调,其中低氧24 h组GCRG213表达水平低于低氧48 h组,Occludin、Claudin-1在mRNA水平(P<0.01;P<0.001)表达下调,其中低氧24 h组表达水平均低于低氧48 h组,Occludin蛋白水平表达在低氧48 h组出现下调(P<0.05)。结论L1-EN变异体GCRG213在人和小鼠正常结肠组织黏膜柱状上皮细胞胞质内存在表达;在体内外模型中,低压低氧暴露下结肠黏膜上皮细胞GCRG213表达升高,同时观察到低压低氧对结肠黏膜紧密连接完整性产生影响,表现为Occludin、Claudin-1蛋白表达水平的降低。 展开更多
关键词 低压低氧 肠黏膜 紧密连接蛋白 GCRG213 line-1
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人工法off-line HDF对血液透析充分性和高同型半胱氨酸血症的影响
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作者 吴飞飞 罗来敏 +2 位作者 范燕娜 张桂玲 龚燕燕 《实用临床医学(江西)》 CAS 2024年第4期19-22,27,共5页
目的探究人工法off-line HDF对维持性血液透析(MHD)患者透析充分性、高同型半胱氨酸血症(HHcy)的影响。方法随机选取2021至2023年于南昌大学第一附属高新医院血液透析中心稳定透析6个月以上的MHD患者30例,进行单中心自身对照研究,时长6... 目的探究人工法off-line HDF对维持性血液透析(MHD)患者透析充分性、高同型半胱氨酸血症(HHcy)的影响。方法随机选取2021至2023年于南昌大学第一附属高新医院血液透析中心稳定透析6个月以上的MHD患者30例,进行单中心自身对照研究,时长6个月。前3个月维持每周2次高通量血液透析(HFHD)联合1次on-line HDF,后3个月维持每周2次人工法off-line HDF联合1次on-line HDF。于研究第3个月、第6个月时用全自动生化分析仪检测透析前后血尿素氮(BUN)、血肌酐(SCr)、β2-微球蛋白(β2MG)、同型半胱氨酸(Hcy)、白蛋白(Alb)、C反应蛋白(CRP)、血红蛋白(Hb)、甲状旁腺素(iPTH)、磷(P)、钾(K)水平;计算血清尿素清除指数(Kt/V)、尿素下降率(URR)和β2MG清除率。结果人工法off-line HDF模式透析的Kt/V、URR及β2MG清除率均较显著高于HFHD模式透析(P<0.05);人工法off-lineHDF模式透析Kt/V、URR及β2MG清除率达到透析充分的百分率分别为83.33%、83.33%和93.33%,均显著高于HFHD模式透析(P<0.05)。与HFHD模式透析时相比,人工法off-lineHDF模式透析结束后,患者透析前Hcy水平降低,Alb水平升高(P<0.05)。结论人工法off-line HDF模式透析可显著增加Kt/V、URR和β2MG清除率,提高MHD患者的透析充分性达标率,且对HHcy具有改善作用。 展开更多
关键词 人工法off-line HDF 血液透析 透析充分性 高同型半胱氨酸血症 血液透析滤过
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基于Hessian矩阵的改进EDlines输电线识别算法
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作者 任茂威 洪炎 +2 位作者 苏静明 许万秋 韦宇豪 《安庆师范大学学报(自然科学版)》 2024年第3期48-55,共8页
随着电力网络的飞速发展,采用无人机搭载高清摄像头来进行输电线巡检已成常态。为提高巡检的实时性和准确性,本研究提出了一种基于Hessian矩阵的改进EDlines输电线识别算法。首先,通过伽马变换对输电线图像进行预处理,利用Hessian矩阵... 随着电力网络的飞速发展,采用无人机搭载高清摄像头来进行输电线巡检已成常态。为提高巡检的实时性和准确性,本研究提出了一种基于Hessian矩阵的改进EDlines输电线识别算法。首先,通过伽马变换对输电线图像进行预处理,利用Hessian矩阵特征值和特征向量以求取像素点主方向和主曲率,并获得输电线主体轮廓,从而摒弃了传统方法中梯度计算锚点和像素方向的繁琐步骤。接着,在主体轮廓基础上连接锚点以得到潜在直线线段像素链,并运用随机抽样一致性(RANSAC)算法来进行线段拟合。最后,根据直线间的距离和角度,迭代拟合以得到最终的输电线。实验结果表明,该方法能应对多种复杂环境下的输电线识别任务,抗干扰能力强,误检率显著降低,为高空输电线巡检提供了可靠的技术支持,具有重要的工程应用价值。 展开更多
关键词 输电线识别 改进EDlines算法 HESSIAN矩阵 RANSAC直线拟合
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Toward a Direct Measurement of the Cosmic Acceleration:The Pilot Observation of HI 21 cm Absorption Line at FAST
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作者 Jiangang Kang Chang-Zhi Lu +1 位作者 Tong-Jie Zhang Ming Zhu 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2024年第7期47-55,共9页
This study presents results on detecting neutral atomic hydrogen(H I)21 cm absorption in the spectrum of PKS PKS1413+13 at redshift z=0.24670041.The observation was conducted by FAST,with a spectral resolution of10 Hz... This study presents results on detecting neutral atomic hydrogen(H I)21 cm absorption in the spectrum of PKS PKS1413+13 at redshift z=0.24670041.The observation was conducted by FAST,with a spectral resolution of10 Hz,using 10 minutes of observing time.The global spectral profile is examined by modeling the absorption line using a single Gaussian function with a resolution of 10 kHz within a 2 MHz bandwidth.The goal is to determine the rate of the latest cosmic acceleration by directly measuring the redshift evolution of the H I 21 cm absorption line with Hubble flow toward a common background quasar over a decade or longer time span.This will serve as a detectable signal generated by the accelerated expansion of the Universe at redshift z<1,referred to as redshift drift z(5)or the SL effect.The measured H I gas column density in this DLA system is approximately equivalent to the initial observation value,considering uncertainties of the spin temperature of a spiral host galaxy.The high signal-to-noise ratio of 57,obtained at a 10 kHz resolution,strongly supports the feasibility of using the H I 21 cm absorption line in DLA systems to accurately measure the redshift drift rate at a precision level of around 10~(-10)per decade. 展开更多
关键词 (cosmology)cosmological parameters-cosmology observations-cosmology theory-(cosmology)dark energy-radio lines ISM-radio lines galaxies-ISM clouds
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Derivative Spectroscopy and its Application at Detecting the Weak Emission/Absorption Lines
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作者 Lihuan Yu Jiangdan Li +4 位作者 Jinliang Wang Jiajia Li Jiao Li Qiang Xi Zhanwen Han 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2024年第3期205-223,共19页
The development of spectroscopic survey telescopes like Large Sky Area Multi-Object Fiber Spectroscopic Telescope(LAMOST),Apache Point Observatory Galactic Evolution Experiment and Sloan Digital Sky Survey has opened ... The development of spectroscopic survey telescopes like Large Sky Area Multi-Object Fiber Spectroscopic Telescope(LAMOST),Apache Point Observatory Galactic Evolution Experiment and Sloan Digital Sky Survey has opened up unprecedented opportunities for stellar classification.Specific types of stars,such as early-type emission-line stars and those with stellar winds,can be distinguished by the profiles of their spectral lines.In this paper,we introduce a method based on derivative spectroscopy(DS)designed to detect signals within complex backgrounds and provide a preliminary estimation of curve profiles.This method exhibits a unique advantage in identifying weak signals and unusual spectral line profiles when compared to other popular line detection methods.We validated our approach using synthesis spectra,demonstrating that DS can detect emission signals three times fainter than Gaussian fitting.Furthermore,we applied our method to 579,680 co-added spectra from LAMOST Medium-Resolution Spectroscopic Survey,identifying 16,629 spectra with emission peaks around the Hαline from 10,963 stars.These spectra were classified into three distinct morphological groups,resulting in nine subclasses as follows.(1)Emission peak above the pseudo-continuum line(single peak,double peaks,emission peak situated within an absorption line,P Cygni profile,Inverse P Cygni profile);(2)Emission peak below the pseudo-continuum line(sharp emission peak,double absorption peaks,emission peak shifted to one side of the absorption line);(3)Emission peak between the pseudo-continuum line. 展开更多
关键词 line identification-line profiles-methods data analysis-techniques spectroscopic-techniques radial velocities
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Evaluation of red soil-bentonite mixtures for compacted clay liners
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作者 A.S.Devapriya T.Thyagaraj 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第2期697-710,共14页
Compacted clay liners are an integral part of the waste landfills,which are provided to contain the leachate within the landfills and protect the surrounding environment.Generally,locally available natural soils are u... Compacted clay liners are an integral part of the waste landfills,which are provided to contain the leachate within the landfills and protect the surrounding environment.Generally,locally available natural soils are used for the construction of compacted clay liners if they satisfy the design criteria.However,not all soils in their natural state satisfy all the design criteria for the liner materials.Thus,there is a definite need to modify the locally available natural soils by blending with bentonite to meet the required design criteria for the liners.In view of this,the present study evaluates the suitability of an Indian red soil enhanced with bentonite as a liner material.To achieve this,a series of experiments were carried out using locally available red soil and bentonite.First,the suitability of the red soil was evaluated as a liner material.The experimental results showed that the red soil met all the selection criteria stipulated by the Environmental Protection Agencies(EPAs)for the liners except the hydraulic conductivity criterion.Therefore,the red soil was mixed with bentonite contents of 10%,20%and 30%,and the red soil-bentonite mixtures were evaluated for their suitability for liners in their compacted state.Further,as the liners in the arid and semi-arid regions are subjected to moisture variations due to seasonal moisture fluctuations and other factors,the red soil-bentonite mixtures were subjected to wetdry cycles,and their suitability was evaluated after wet-dry cycles.The experimental results revealed that all the red soil-bentonite mixtures met the stipulated EPA criteria for the liners in the as-compacted state.However,the red soil-bentonite mixtures with 20%and 30%bentonite contents only satisfied the hydraulic conductivity requirement even after wet-dry cycles.The experimental findings were supplemented with the microstructural insights captured through digital camera images,scanning electron microscopy(SEM),and mercury intrusion porosimetry(MIP)studies. 展开更多
关键词 Compacted clay lines Hydraulic conductivity Wet-dry cycles Microstructure
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ST-LaneNet: Lane Line Detection Method Based on Swin Transformer and LaneNet
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作者 Yufeng Du Rongyun Zhang +3 位作者 Peicheng Shi Linfeng Zhao Bin Zhang Yaming Liu 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2024年第1期130-145,共16页
The advancement of autonomous driving heavily relies on the ability to accurate lane lines detection.As deep learning and computer vision technologies evolve,a variety of deep learning-based methods for lane line dete... The advancement of autonomous driving heavily relies on the ability to accurate lane lines detection.As deep learning and computer vision technologies evolve,a variety of deep learning-based methods for lane line detection have been proposed by researchers in the field.However,owing to the simple appearance of lane lines and the lack of distinctive features,it is easy for other objects with similar local appearances to interfere with the process of detecting lane lines.The precision of lane line detection is limited by the unpredictable quantity and diversity of lane lines.To address the aforementioned challenges,we propose a novel deep learning approach for lane line detection.This method leverages the Swin Transformer in conjunction with LaneNet(called ST-LaneNet).The experience results showed that the true positive detection rate can reach 97.53%for easy lanes and 96.83%for difficult lanes(such as scenes with severe occlusion and extreme lighting conditions),which can better accomplish the objective of detecting lane lines.In 1000 detection samples,the average detection accuracy can reach 97.83%,the average inference time per image can reach 17.8 ms,and the average number of frames per second can reach 64.8 Hz.The programming scripts and associated models for this project can be accessed openly at the following GitHub repository:https://github.com/Duane 711/Lane-line-detec tion-ST-LaneNet. 展开更多
关键词 Autonomous driving Lane line detection Deep learning Swin transformer
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Optimizing profile line interval for enhanced accuracy in rock joint morphology and shear strength assessments
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作者 Leibo Song Quan Jiang +5 位作者 Shigui Du Jiamin Song Gang Wang Yanting Gu Xingkai Wang Jinzhong Wu 《International Journal of Mining Science and Technology》 SCIE EI CAS CSCD 2024年第5期587-608,共22页
2D profile lines play a critical role in cost-effectively evaluating rock joint properties and shear strength.However, the interval(ΔI_(L)) between these lines significantly impacts roughness and shear strength asses... 2D profile lines play a critical role in cost-effectively evaluating rock joint properties and shear strength.However, the interval(ΔI_(L)) between these lines significantly impacts roughness and shear strength assessments. A detailed study of 45 joint samples using four statistical measures across 500 different ΔI_(L)values identified a clear line interval effect with two stages: stable and fluctuation-discrete.Further statistical analysis showed a linear relationship between the error bounds of four parameters,shear strength evaluation, and their corresponding maximum ΔI_(L)values, where the gradient k of this linear relationship was influenced by the basic friction angle and normal stress. Accounting for these factors,lower-limit linear models were employed to determine the optimal ΔI_(L)values that met error tolerances(1%–10%) for all metrics and shear strength. The study also explored the consistent size effect on joints regardless of ΔI_(L)changes, revealing three types of size effects based on morphological heterogeneity.Notably, larger joints required generally higher ΔI_(L)to maintain the predefined error limits, suggesting an increased interval for large joint analyses. Consequently, this research provides a basis for determining the optimal ΔI_(L), improving accuracy in 2D profile line assessments of joint characteristics. 展开更多
关键词 Rock joint ROUGHNESS Shear strength Size effect Profile line interval effect
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An Implementation of Multiscale Line Detection and Mathematical Morphology for Efficient and Precise Blood Vessel Segmentation in Fundus Images
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作者 Syed Ayaz Ali Shah Aamir Shahzad +4 位作者 Musaed Alhussein Chuan Meng Goh Khursheed Aurangzeb Tong Boon Tang Muhammad Awais 《Computers, Materials & Continua》 SCIE EI 2024年第5期2565-2583,共19页
Diagnosing various diseases such as glaucoma,age-related macular degeneration,cardiovascular conditions,and diabetic retinopathy involves segmenting retinal blood vessels.The task is particularly challenging when deal... Diagnosing various diseases such as glaucoma,age-related macular degeneration,cardiovascular conditions,and diabetic retinopathy involves segmenting retinal blood vessels.The task is particularly challenging when dealing with color fundus images due to issues like non-uniformillumination,low contrast,and variations in vessel appearance,especially in the presence of different pathologies.Furthermore,the speed of the retinal vessel segmentation system is of utmost importance.With the surge of now available big data,the speed of the algorithm becomes increasingly important,carrying almost equivalent weightage to the accuracy of the algorithm.To address these challenges,we present a novel approach for retinal vessel segmentation,leveraging efficient and robust techniques based on multiscale line detection and mathematical morphology.Our algorithm’s performance is evaluated on two publicly available datasets,namely the Digital Retinal Images for Vessel Extraction dataset(DRIVE)and the Structure Analysis of Retina(STARE)dataset.The experimental results demonstrate the effectiveness of our method,withmean accuracy values of 0.9467 forDRIVE and 0.9535 for STARE datasets,aswell as sensitivity values of 0.6952 forDRIVE and 0.6809 for STARE datasets.Notably,our algorithmexhibits competitive performance with state-of-the-art methods.Importantly,it operates at an average speed of 3.73 s per image for DRIVE and 3.75 s for STARE datasets.It is worth noting that these results were achieved using Matlab scripts containing multiple loops.This suggests that the processing time can be further reduced by replacing loops with vectorization.Thus the proposed algorithm can be deployed in real time applications.In summary,our proposed system strikes a fine balance between swift computation and accuracy that is on par with the best available methods in the field. 展开更多
关键词 line detector vessel detection LOCALIZATION mathematical morphology image processing
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Characterization of the infectivity of an Indonesian Zika virus strain in mammalian cell lines
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作者 Justus Thomas Obiajulu Sievers Anom Bowolaksono R.Tedjo Sasmono 《Asian Pacific Journal of Tropical Biomedicine》 SCIE CAS 2024年第5期215-224,共10页
Objective:To characterize the infection patterns and growth characteristics of the Zika virus(ZIKV)strain JMB-185 from Indonesia in various mammalian cell lines.Methods:ZIKV was grown in human(A549,HEK293,HepG2,Huh7,J... Objective:To characterize the infection patterns and growth characteristics of the Zika virus(ZIKV)strain JMB-185 from Indonesia in various mammalian cell lines.Methods:ZIKV was grown in human(A549,HEK293,HepG2,Huh7,Jurkat,and THP-1)and non-human mammalian(RAW264.7,Vero,and Vero76)cell lines.Viral replication kinetics were measured using plaque assay,while intra-and extracellular viral RNA concentrations were assessed using RT-PCR.Flow cytometry was used to quantify the infected cells and cell viability was measured using an MTT assay.The ability of ZIKV to infect cell lines was visualized using a fluorescence immunostaining assay.Results:This ZIKV strain preferentially infected the lung,kidney,and liver cell lines A549,HEK293,Huh7,Vero,and Vero76,but not the immune cells Jurkat,RAW264.7,and THP-1.By contrast,the ZIKV showed no sign of infection in HepG2 cells,while maintaining viral titer over 3 days post-infection,with no infection recorded in immunostaining,no increase in viral RNA,and no indication of cell deterioration.Conclusions:The Indonesian ZIKV strain has a similar infection profile as other strains,except for its poor infectivity on HepG2 cells.Information on the growth characteristics of Indonesia ZIKV will help expand our understanding of the biology of ZIKV which will be useful for various applications including antiviral discovery. 展开更多
关键词 Zika virus Infectivity REPLICATION Cell lines In vitro
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Analysis of mechanical strengths of extreme line casing joint considering geometric, material, and contact nonlinearities
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作者 Ji-Yun Zhang Chi Peng +4 位作者 Jian-Hong Fu Quan Cao Yu Su Jian-Yun Pang Zi-Qiang Yu 《Petroleum Science》 SCIE EI CAS CSCD 2024年第3期1992-2004,共13页
To address the challenges associated with difficult casing running,limited annular space,and poor cementing quality in the completion of ultra-deep wells,the extreme line casing offers an effective solution over conve... To address the challenges associated with difficult casing running,limited annular space,and poor cementing quality in the completion of ultra-deep wells,the extreme line casing offers an effective solution over conventional casings.However,due to its smaller size,the joint strength of extreme line casing is reduced,which may cause failure when running in the hole.To address this issue,this study focuses on the CST-ZTΦ139.7 mm×7.72 mm extreme line casing and employs the elastic-plastic mechanics to establish a comprehensive analysis of the casing joint,taking into account the influence of geometric and material nonlinearities.A finite element model is developed to analyze the forces and deformations of the extreme line casing joint under axial tension and external collapse load.The model investigates the stress distribution of each thread tooth subjected to various tensile forces and external pressures.Additionally,the tensile strength and crushing strength of the extreme line casing joint are determined through both analytical and experimental approaches.The findings reveal that,under axial tensile load,the bearing surface of each thread tooth experiences uneven stress,with relatively high equivalent stress at the root of each thread tooth.The end thread teeth are valuable spots for failure.It is observed that the critical fracture axial load of thread decreases linearly with the increase of thread tooth sequence.Under external pressure,the circumferential stress is highest at the small end of the external thread,leading to yield deformation.The tensile strength of the joint obtained from the finite element model exhibits a relative error of less than 7%compared to the analytical and experimental values,proving the reliability of the finite element model.The tensile strength of the joint is 3091.9 k N.Moreover,in terms of anti-collapse capability,the joints demonstrate higher resistance to collapse compared to the casing body,which is consistent with the test results where the pipe body experiences collapse and failure while the joints remain intact during the experiment.The failure load of the casing body under external collapse pressure is 87.4 MPa.The present study provides a basic understanding of the mechanical strengths of extreme line casing joint. 展开更多
关键词 Extreme line casing Elastic-plastic mechanics Finite element analysis Tensile strength Collapse strength
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