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明渠非标准断面法测流水位流量关系的率定及影响因素分析
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作者 梁慧真 宗全利 +2 位作者 刘贞姬 谢炎 刘冬冬 《排灌机械工程学报》 CSCD 北大核心 2024年第2期147-153,160,共8页
为探究明渠非标准断面法测流的水位流量关系曲线的率定问题,以新疆第三师某团场25处渠道量水断面为研究对象,利用FlowTracker 2手持式声学多普勒流速仪进行了水位流量关系率定工作.根据实测结果,率定了各渠道量水断面的水位流量关系曲线... 为探究明渠非标准断面法测流的水位流量关系曲线的率定问题,以新疆第三师某团场25处渠道量水断面为研究对象,利用FlowTracker 2手持式声学多普勒流速仪进行了水位流量关系率定工作.根据实测结果,率定了各渠道量水断面的水位流量关系曲线,并对所率定出的曲线进行了符号检验、适线检验和偏离数值检验及误差分析,在此基础上,对流量拟合参数的影响因素进行了分析.结果表明:所率定的25处渠道量水断面中,14处具有稳定的水位流量关系,5处受回水影响、6处受渠道淤积影响为不稳定的水位流量关系;在渠道粗糙系数Ra、边坡系数m及坡降i相同的条件下,流量拟合参数与渠道底宽b总体上呈正相关;在渠道粗糙系数Ra、边坡系数m及底宽b相同的条件下,流量拟合参数与渠道坡降i总体上呈负相关.研究结果可以为灌区自动化量水设备测流准确性的校核提供参考依据. 展开更多
关键词 标准断面 水位流量关系曲线 率定 流量拟合参数 自动化量水
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宝石折射仪点测法的拓展——非标准态油滴影像的读数与应用
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作者 沈雁翱 《实验室检测》 2024年第3期13-17,共5页
目的分析点测法中异形油滴影像出现的原因,拓宽点测法的适用范围,提高检测效率。方法分别用宝石折射仪对刻面型、弧面型、抛光、磨砂不同形态组合的10个典型样品进行点测,研究了异形油滴影像不出现平直的明暗分界线、但有明暗面积变化... 目的分析点测法中异形油滴影像出现的原因,拓宽点测法的适用范围,提高检测效率。方法分别用宝石折射仪对刻面型、弧面型、抛光、磨砂不同形态组合的10个典型样品进行点测,研究了异形油滴影像不出现平直的明暗分界线、但有明暗面积变化以及异形油滴影像没有明暗面积的变化,只有一小块亮斑随着油滴影像的移动而移动这两种非标准态点测法的读数方法。结果在点测出现油滴影像非标准态时,依然可以快速读出可靠的宝玉石折射率点测值。结论本研究技术将点测法的适用范围拓展至刻面宝石的点测法折射率测定、细磨砂面宝石的点测法折射率测定、折射率超出折射仪量程的判定3个具体场景。 展开更多
关键词 折射仪 标准点测 读数
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非标准方法在扩张测度上的一个应用 被引量:1
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作者 张福泰 《陕西师大学报(自然科学版)》 CSCD 1991年第2期70-71,共2页
本文在k-饱和的扩大非标准模型中讨论,其中k>card(X)。有关非标准分析的基本知识参见[1],关于Loeb测度的构造及其理论参见[2,3]。令S={{x∈X:f(x)<α}:f∈c(X),α∈R},φ是由S生成的代数。X上的Baire α-代数记为φ(X)。引理1
关键词 有限可加测度 贝利扩张 非标准法
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富水断层非标准三角堰测法流量计算方法及工程应用 被引量:2
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作者 牟勇忠 周传波 +5 位作者 肖文芳 蒋楠 吴廷尧 杜超飞 刘赶平 刘磊 《地质科技通报》 CAS CSCD 北大核心 2020年第6期185-192,共8页
公路、铁路、水利水电、矿山等隧道工程建设和运营过程中,不可避免地会遭遇塌方、突涌水等地质灾害问题,围岩失稳破坏和渗流突变是发生突水的直接原因。为查明龙南隧道F8富水断层洞身范围涌水来源及其涌水量的大小,采用非标准三角堰测... 公路、铁路、水利水电、矿山等隧道工程建设和运营过程中,不可避免地会遭遇塌方、突涌水等地质灾害问题,围岩失稳破坏和渗流突变是发生突水的直接原因。为查明龙南隧道F8富水断层洞身范围涌水来源及其涌水量的大小,采用非标准三角堰测法结合矩形堰测法现场监测F8断层地表上、下游流量。本研究提出非标准三角堰测法的基本概念,并根据标准三角堰测法流量公式,结合流量的等效原理,推导出了非标准三角堰测法流量公式。通过理论与实测数据进行比较,证明了本公式的合理性。研究结果表明,非标准三角堰测法流量公式的推导为现场流量实测提供了方便,克服了标准三角堰测法公式适用范围不足的缺点,为分析断层破碎带洞身围岩范围内涌水量大小提供了可靠依据。 展开更多
关键词 富水断层 标准三角堰测 矩形堰测 流量公式 流量等效原理
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在超实数域上对标准分析的级数判别法中不定型的区分
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作者 沈呈民 《东北师大学报(自然科学版)》 CAS CSCD 1990年第1期17-20,共4页
本文将用非标准分析方法在超实数领域内对标准分析的级数判别法中的收敛域与发散域进行讨论.对标准分析中关于级数收敛与发散的不定型部分用非标准分析工具在超实数域内加以区分,并给出几何级数相应的判别定理.
关键词 超实数域 级数 标准分析
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微分方程中含有双小参数的边值问题
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作者 程建华 祝清 《安徽大学学报(自然科学版)》 CAS 1991年第1期16-20,48,共6页
本文用非标准分析方法讨论了常微分方程奇异摄动理论中一类边值问题,同时并给出了含双小参数方程存在跳跃点的条件。
关键词 退化方程 边值问题 标准分析
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新西兰英语的特点 被引量:1
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作者 李桂南 《外语教学》 CSSCI 北大核心 1998年第1期76-76,共1页
新西兰英语的特点新西兰是一个年轻的国家,80%为欧洲人,其中大多数为英国移民。新西兰英语只有150余年的历史。除了在新西兰南岛的Southland省以及Otago省Dunedin市有明显的苏格兰方言外(该市居住着大批... 新西兰英语的特点新西兰是一个年轻的国家,80%为欧洲人,其中大多数为英国移民。新西兰英语只有150余年的历史。除了在新西兰南岛的Southland省以及Otago省Dunedin市有明显的苏格兰方言外(该市居住着大批苏格兰移民),新西兰英语中并无其它... 展开更多
关键词 新西兰英语 毛利语 《外语教学与研究》 新西兰人 标准 美国英语 英国英语 语音特点 地理位置 英语语
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Research on the Arc Interpolation for the Nonstandard Section Curve of the Piston 被引量:2
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作者 秦月霞 胡德金 《Journal of Donghua University(English Edition)》 EI CAS 2004年第4期95-97,共3页
The transverse section of piston skirt is not a standard circle and is with high precision. So the section curve should be interpolated through the high accuracy method of circular arc interpolation before NC machinin... The transverse section of piston skirt is not a standard circle and is with high precision. So the section curve should be interpolated through the high accuracy method of circular arc interpolation before NC machining. In order to smooth the connection of adjacent arcs and shorten the NC machining program, an interpolation method based on Chebyshev theory of function approximation is proposed here. According to the analysis of the interpolation error, the algorithm is simple and with high precision. By this way the fewest interpolating circular arc segments can be got, and the manufacture requirement is satisfied with the circular arc interpolating curves. 展开更多
关键词 PISTON arc interpolation ellipse curve
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Sarty's Initiation in Faulkner's Barn Burning
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作者 LIU Ke-dong LIN Shi-rong 《Journal of Literature and Art Studies》 2013年第5期327-331,共5页
Barn Burning (1939), one of William Faulkner's outstanding short stories, is not only about the struggles between different classes, but also depicts the boy's initiation into manhood after he sees his father's r... Barn Burning (1939), one of William Faulkner's outstanding short stories, is not only about the struggles between different classes, but also depicts the boy's initiation into manhood after he sees his father's rash and irrational revenge activities. The boy protagonist's constant dilemma is between whether to protect his father's authority due to the old fierce blood tie or to disclose his father's quasi-criminal attempts according to his own standard of justice. Based on close reading of the text, this paper aims to make a detailed analysis of the different factors (paternalism and his own idea of justice) that influence the boy's choices at different stages. After the long-time struggle, the boy finally chooses to follow his own standards of right and justice, which signifies his gradual initiation into manhood. 展开更多
关键词 Barn Burning JUSTICE blood tie INITIATION
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Pattern characteristics in patients with primary liver cancer in different clinical stages 被引量:3
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作者 Qin Liping Meng Jing +2 位作者 Lang Qingbo Liu Long Li Bai 《Journal of Traditional Chinese Medicine》 SCIE CAS CSCD 2015年第1期47-53,共7页
OBJECTIVE: To explore the characteristics of prima- ry liver cancer in terms of Traditional Chinese Medi-cine (TCM) by analyzing the variations of the patterns along with the clinical stages. METHODS: The patients... OBJECTIVE: To explore the characteristics of prima- ry liver cancer in terms of Traditional Chinese Medi-cine (TCM) by analyzing the variations of the patterns along with the clinical stages. METHODS: The patients who were hospitalized in the Changhai Hospital of Traditional Chinese Medi- cine dated from March 1999 to December 2008 were included in this retrospective study. The patients were grouped according to their cancer stag- es, and their patterns were judged and quantified according to the "Standard diagnosis and quantitative criteria of the common patterns in primary liv-er cancer" formulated by the Changhai Hospital of Traditional Chinese Medicine. Statistics methods included ANOVA and nonparametric test, among others.RESULTS: The data of the 398 newly diagnosed patients showed that Qi Stagnation, Blood Stasis, and Dampness patterns were more frequent than the other basic patterns with relatively high scores; patterns of Liver Qi Stagnation, Liver Blood Stasis, and Dampness Heat were more than the other complex patterns and scored relatively high. Scores of Dampness and Liver Qi Stagnation patterns varied among the groups at different stages and the differences were statistically significant (PDampeness= 0.002, PLiver Qi Stagnation : 0.020). The highest scores of Damp- ness pattern and Liver Qi Stagnation pattern corresponded with Stage Ⅲ b, and Stage Ⅲ a, respectively. Dampness pattern frequency was higher (P = 0.001) in the Stage Ⅲb group than in other groups.CONCLUSION: Pattern characteristics in patients with primary liver cancer of different clinical stages might manifest in the variations of the Dampness pattern along the process of the disease and the major pathogenic factor of primary liver cancer might be Dampness. 展开更多
关键词 Carcinoma hepatocellular Neoplasmstaging Medicine Chinese traditional PATTERN
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Combinations of nonstandard finite difference schemes and composition methods with complex time steps for population models
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作者 Cuicui Liao Xiaohua Ding Jiuzhen Liang 《International Journal of Biomathematics》 2016年第4期1-14,共14页
We propose an efficient numerical method for two population models, based on the nonstandard finite difference (NSFD) schemes and composition methods with complex time steps. The NSFD scheme is able to give positive... We propose an efficient numerical method for two population models, based on the nonstandard finite difference (NSFD) schemes and composition methods with complex time steps. The NSFD scheme is able to give positive numerical solutions that satisfy the conservation law, which is a key property for biological population models. The accuracy is improved by using the composition methods with complex time steps. Numerical tests on the plankton nutrient model and whooping cough model are presented to show the efficiency and advantage of the proposed numerical method. 展开更多
关键词 Nonstandard finite difference schemes composition methods with complextime steps population models positive numerical solutions conservation laws.
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