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圆柱体岩块变角板试验结果分析 被引量:1
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作者 黄英娣 《桂林工学院学报》 1997年第2期170-172,共3页
将圆柱体岩石试件放在一对自制的半圆形钢制卡环内,进行变角板试验,并将其结果与标准正方体试件的试验结果进行比较,发现两种不同形状岩样的内聚力c值及内摩擦角φ值比较接近,且圆柱体试件试验所得剪应力τ与正应力σ之间的相关系... 将圆柱体岩石试件放在一对自制的半圆形钢制卡环内,进行变角板试验,并将其结果与标准正方体试件的试验结果进行比较,发现两种不同形状岩样的内聚力c值及内摩擦角φ值比较接近,且圆柱体试件试验所得剪应力τ与正应力σ之间的相关系数大于096,破坏面理想,破裂体两半基本对称,故圆柱体试件变角板试验结果具有一定的可靠程度。 展开更多
关键词 圆柱体 正方体 岩块 变角板 试验结果 岩石力学
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不同受力维度下红砂岩失稳评判指标研究
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作者 林格 宫凤强 《黄金科学技术》 CSCD 2018年第2期195-202,共8页
为了研究不同受力维度下岩石峰值应力、峰值应变与失稳的关系,分别对红砂岩进行一维、二维、三维受力条件下的单轴抗压试验、变角板剪切试验和直接剪切试验以及三轴压缩试验。试验结果显示:单轴压缩试验中,峰值应力和峰值应变变异系数... 为了研究不同受力维度下岩石峰值应力、峰值应变与失稳的关系,分别对红砂岩进行一维、二维、三维受力条件下的单轴抗压试验、变角板剪切试验和直接剪切试验以及三轴压缩试验。试验结果显示:单轴压缩试验中,峰值应力和峰值应变变异系数分别为6.61%和9.36%;变角板剪切试验中,峰值应力和峰值应变平均变异系数分别为5.69%和19.81%;直接剪切试验中,峰值应力和峰值应变平均变异系数分别为4.32%和14.74%;三轴压缩试验中,峰值应力和峰值应变平均变异系数分别为6.03%和7.44%。上述研究表明:当红砂岩处于一维和三维受力状态时,峰值应力和峰值应变均可以作为评判红砂岩是否失稳的指标,但峰值应力比峰值应变作为评判指标的可靠性更高;当红砂岩处于二维受力状态时,只有峰值应力能作为评判红砂岩是否失稳的指标。上述研究规律不仅对评判室内试验中岩石是否失稳具有重要意义,而且对评判岩土工程中岩石是否处于安全状态提供理论依据。 展开更多
关键词 单轴抗压试验 变角板剪切试验 直接剪切试验 三轴压缩试验 峰值应力 峰值应 异系数
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软弱岩石本身抗剪断试验的方法研究
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作者 尹玉英 《水利水电建设》 1992年第4期21-24,共4页
关键词 岩石力学 抗剪断 试验 变角板
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A novel algorithm for a rotation invariant template matching 被引量:1
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作者 LEI Ming ZHANG Guang-jun 《Optoelectronics Letters》 EI 2008年第5期379-383,共5页
A novel algorithm for a rotation invariant template matching is proposed when the fluctuating scope of the rotation angle is limited within the region of [-20°,20°]. The matching candidates are selected usin... A novel algorithm for a rotation invariant template matching is proposed when the fluctuating scope of the rotation angle is limited within the region of [-20°,20°]. The matching candidates are selected using a computationally low cost improved correlation algorithm. "AND" operation is adopted to reduce the computational cost. Therefore the algorithm improves the matching speed consumedly. The simulation results verify the efficiency of the proposed method. Moreover,when the size of reference image is fixed,the advantage of this time-saving algorithm is more obvious as the increase of the size of the real time image. The matching speed of the proposed method is over 20 times faster than the speed of the two-level pyramid decomposing accelerating method. 展开更多
关键词 运算法则 旋转 匹配
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Peripheral deep anterior lamellar keratoplasty using a cryopreserved donor cornea for Terrien's marginal degeneration 被引量:3
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作者 Dan HUANG Wen-ya QIU +2 位作者 Bei ZHANG Bing-hong WANG Yu-feng YAO 《Journal of Zhejiang University-Science B(Biomedicine & Biotechnology)》 SCIE CAS CSCD 2014年第12期1055-1063,共9页
Objective: To evaluate the clinical efficacy of peripheral deep anterior lamellar keratoplasty (DALK) using a cryopreserved donor cornea for Terrien's marginal degeneration (TMD). Methods: Thirty-one eyes of 27... Objective: To evaluate the clinical efficacy of peripheral deep anterior lamellar keratoplasty (DALK) using a cryopreserved donor cornea for Terrien's marginal degeneration (TMD). Methods: Thirty-one eyes of 27 patients with TMD underwent peripheral DALK using cryopreserved donor corneas, According to the distance between the inner edge of the lesion and the limbus, a ring-shaped or D-shaped DALK was performed. All grafts were stored at -20 ℃. Cryopreserved comeoscleral rims were prepared for ring-shaped grafts and cryopreserved whole eyeballs were prepared for D-shaped grafts. The general conditions, intraoperative performance, postoperative corneal reconstruc- tion, astigmatism, best corrected visual acuity (BCVA), and various complications were analyzed. Results: Ring-shaped DALK was performed in 28 eyes and D-shaped DALK was performed in 3 eyes. Postoperative follow-up time was (28.4±24.8) months. There was evidence of inflammation before surgery in 12 eyes (38.7%) and intraoper- ative perforation occurred in 13 eyes (41.9%). The corneal structures of all eyes were reconstructed. Postoperative astigmatism and BCVA showed improvement (both P=0.00) except for cases that underwent D-shaped DALK. Ten eyes (32.2%) developed transient ocular hypertension and one eye (3.2%) developed secondary glaucoma. No pri- mary disease recurrence or corneal allograft rejection was observed. Conclusions: Peripheral DALK for TMD using cryopreserved donor tissue is an effective technique that eliminates rejection and extends the use of donor eyes. Inflammatory history or intraoperative perforation has no adverse effect on graft recovery. However, D-shaped DALK did not achieve good visual outcomes. 展开更多
关键词 Terrien's marginal degeneration (TMD) Deep anterior lamellar keratoplasty (DALK) CRYOPRESERVATION
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