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机器人切石法 麻省理工学院肖恩·科利尔纪念碑的建造
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作者 尹美真 埃里克.霍威尔 张立名 《时代建筑》 2015年第5期92-95,共4页
麻省理工学院肖恩·科利尔纪念碑是为了纪念2013年在波士顿马拉松爆炸案中中枪身亡的肖恩·科利尔军官而建造的。文章介绍了这一永久性建筑物的设计与建造过程。设计将当代的数字建造技术、结构分析软件和计算技术与古老的纯受... 麻省理工学院肖恩·科利尔纪念碑是为了纪念2013年在波士顿马拉松爆炸案中中枪身亡的肖恩·科利尔军官而建造的。文章介绍了这一永久性建筑物的设计与建造过程。设计将当代的数字建造技术、结构分析软件和计算技术与古老的纯受压穹顶技术相结合,创造出由硬石构成的五向穹顶和内部反射的中空拱形结构。这一建造包含由计算机控制的锯石和机械臂切石过程,以创造出多样的曲面石块。巨大的石块被运至现场由泥瓦匠依照复杂的搭建顺序装配完成。从方法论而言,麻省理工学院肖恩·科利尔纪念碑的设计流程是一个来回推敲的过程,即不断地进行数字模拟,在构建物理模型、模拟模型和数字模型的过程中进行优化设计。这一设计同时展现了以新兴数字建造方法为代表的当代技术和以传统石块砌筑技术为代表的永恒手工艺。 展开更多
关键词 结构找形 机器人切石法 数字化建造 传统手工艺
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粗野建构 当代建筑中的悖论 被引量:1
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作者 戈沃克.哈图尼安 周渐佳 《时代建筑》 2012年第2期50-59,共10页
文章通过重拾20世纪50年代的新粗野主义,尤其是粗野主义与图像、材料性的特殊关联,来检视当代建筑师的部分作品,借以说明建构思考在当下境况中存在的悖论。我们会想起戈特弗里德·森佩尔有关戏剧化建构的理论,还有"饰面"... 文章通过重拾20世纪50年代的新粗野主义,尤其是粗野主义与图像、材料性的特殊关联,来检视当代建筑师的部分作品,借以说明建构思考在当下境况中存在的悖论。我们会想起戈特弗里德·森佩尔有关戏剧化建构的理论,还有"饰面"面临着从建造形式转变成为文化范畴时所具备的批判性。然而,如果现在建筑批评所面临的紧迫议题恰是奇观的审美对当下文化的渗透,情况又会如何?隐含的悖论突出了"粗野建构学"中对"切割"这个专属于切石术与电影术的概念的寓言式借鉴。对于由切石术以及数字机器中生产出来的、承载图像的图纸而言,几何有着至关重要的作用;无独有偶,也有一部分当代建筑师的工作是致力于将几何加入到雕塑式建构之中。现在对独石切割般的建筑的取向其实有着更深远的意味;独石切割般建筑的建构切割具备简化后现代交流方式的潜力。其次,当形式自治成为一种趋势,当用奇观图像来矫饰数字化的复制形式成为流行的新潮,整石切割般的建筑中内含的匿名性(它的不可接近性)至关重要。 展开更多
关键词 图像 切石法 雕塑式建构 建构的戏剧性
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Exploration of Methods for Preparation of Cattle Eyeball Paraffin Sections 被引量:1
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作者 邓立新 郭延俭 +4 位作者 王绿林 王朝阳 董海聚 李杨 贺丛 《Agricultural Science & Technology》 CAS 2014年第1期71-73,共3页
[Objective] This study aimed to establish a new method for preparing paraffin sections of cattle eyebal s. [Method] The conventional method was used to prepare paraffin sections for cattle eyebal s in the control and ... [Objective] This study aimed to establish a new method for preparing paraffin sections of cattle eyebal s. [Method] The conventional method was used to prepare paraffin sections for cattle eyebal s in the control and a new method termed&quot;opening a window on cornea and refixation&quot; was used to prepare paraffin sections for cattle eyebal s in the treatment group. [Result] After the prepared specimens in the treatment group were fixed, it could be macroscopical y observed that retina and choroid were closely connected, with detachment occurring at a smal portion be-tween the two. According to the paraffin sections, it was microscopical y observed that the continuity of trabecular meshwork was intact, as wel as the continuity be-tween different layers of eyebal wal , without detachment between them, no retinal detachment, no shrinkage of each layer of tissue cells. [Conclusion] This study pro-vides a foundation for the basic research and pathological study of eyebal s. 展开更多
关键词 CATTLE EYEBALL Paraffin sections "Opening a window on cornea andrefixation" method
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A Paraffin Sectioning Method Without Using the Microtome and an Analysis Method for Optical Information of the Plant Anatomical Digital Photographs
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作者 洪亚平 《Agricultural Science & Technology》 CAS 2010年第6期28-31,共4页
[Objective] The research aimed to study a paraffin method without using the microtome,and also introduced an analysis method for optical information of the plant anatomical digital photographs.[Method] The plant mater... [Objective] The research aimed to study a paraffin method without using the microtome,and also introduced an analysis method for optical information of the plant anatomical digital photographs.[Method] The plant material softened or not was embedded in paraffin according to the paraffin method.Cut the thin paraffin sections from the paraffin block with a sharp two-sided blade under anatomical lens.The thin material sections rolled up when they were cut off.Took the section rolls to a slide,and then heated them to melt the paraffin section roll.When the paraffin melted,the sections of plant material were rolled out.After the common or simplified procedures of staining and mounting,the preparations were finished.When an anatomical digital photograph was processed,copy it into the word file and two copies of the original photograph were obtained.One copy was selected to make it to be a negative photograph,and then press the key "Press Screen" to copy the screen frame.After it was copied into the word file,cut of the unnecessary parts and other operations were carried out,then processed photograph was obtained.[Results] The anatomical preparation for research was gotten.The analyzed digital photograph of the leaf structure of Salix matsudana var.matsudana f.tortuosa has some a three-dimensional effect,and the different leaf structures and cells,e.g.cuticle,cell wall,protoplast,vein,etc.can be identified easily.[Conclusion]The paraffin method without using the microtome has advantages of low cost and higher efficiency,which could be applied by the beginner or in the time without a microtome to be used.The analysis of the plant anatomical digital photographs can acquire more structural information than the original digital photographs,which shows the potentiality and prospects of the optical information analysis of the microscopic imagery and its digital photograph. 展开更多
关键词 Paraffin method Digital photograph Optical information Analysis
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俯卧位和斜仰截石位双镜联合取石术治疗老年肾结石的效果研究
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作者 王竞 《中国科技期刊数据库 医药》 2022年第12期48-51,共4页
探讨高龄肾结石患者行俯卧位、仰仰式截石位联合手术的疗效。方法 选取70名老年 KS病人,按照随机数字表分成两组,分别为35例,观察组与对照组。两组患者行经皮肾镜加输尿管软镜取石,对照组采用俯卧位,观察组采用斜仰式截石法。结果 结石... 探讨高龄肾结石患者行俯卧位、仰仰式截石位联合手术的疗效。方法 选取70名老年 KS病人,按照随机数字表分成两组,分别为35例,观察组与对照组。两组患者行经皮肾镜加输尿管软镜取石,对照组采用俯卧位,观察组采用斜仰式截石法。结果 结石清除率、手术相关指标、术后并发症率均高于对照组。结果 观察组结石清除率91.43%,与对照组71.43%相比,差异有显著性(P<0.05);观察组术后出血量低于对照组,住院时间和手术时间均低于对照组(P<0.05);术后并发症发生率为5.71%,与对照组相比,术后并发症的发生率为25.71%,有显著性差异(P<0.05)。结论 双镜下斜仰段截石位联合手术对老年 KS病人有良好的疗效,能明显改善肾结石的清除率,减少合并并发症的发生。 展开更多
关键词 斜仰式切石法 俯卧位 肾结石 经皮肾镜 输尿管软镜取石法
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Laparoscopic cholecystectomy in a patient with situs inversus totalis 被引量:3
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作者 Unal Aydin Omer Unalp +3 位作者 Pinar Yazici Baris Gurcu Murat Sozbilen Ahmet Coker 《World Journal of Gastroenterology》 SCIE CAS CSCD 2006年第47期7717-7719,共3页
Currently, laparoscopic cholecystectomy is an undoubtfully optimal treatment of cholelithiasis. What about performing this procedure on a patient with situs inversus totalis and what are the difficulties of this opera... Currently, laparoscopic cholecystectomy is an undoubtfully optimal treatment of cholelithiasis. What about performing this procedure on a patient with situs inversus totalis and what are the difficulties of this operation for a right-handed surgeon? We presented a 35-year-old man with unknown situs inversus totalis who was admitted with epigastric pain and digestive problems. Ultrasonography and computed tomography of the abdomen confirmed the diagnosis of a gallstone. Besides, the liver and gallbladder were on the left side and the spleen was on the right. All systems were left-right reversal as mirror image in all diagnostic studies. Laparoscopic cholecystectomy was safely performed, despite of difficulties of situs inversus. The patient was discharged on postoperative day 1. It should be considered that existence of other anomalies may easily cause uninvited injuries. In the patients with situs inversus, laparoscopic cholecystectomy can be safely managed by an experienced surgeon through laparoscopy, and also hepatobiliary surgery. 展开更多
关键词 Situs inversus totalis Laparoscopic cholecystectomy CHOLELITHIASIS
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Specific energy optimization in sawing of rocks using Taguchi approach 被引量:2
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作者 Izzet Karakurt 《Journal of Central South University》 SCIE EI CAS 2014年第1期365-372,共8页
This work aims at selecting optimal operating variables to obtain the minimum specific energy(SE) in sawing of rocks.A particular granite was sampled and sawn by a fully automated circular diamond sawblades.The periph... This work aims at selecting optimal operating variables to obtain the minimum specific energy(SE) in sawing of rocks.A particular granite was sampled and sawn by a fully automated circular diamond sawblades.The peripheral speed,the traverse speed,the cut depth and the flow rate of cooling fluid were selected as the operating variables.Taguchi approach was adopted as a statistical design of experimental technique for optimization studies.The results were evaluated based on the analysis of variance and signal-to-noise ratio(S/N ratio).Statistically significant operating variables and their percentage contribution to the process were also determined.Additionally,a statistical model was developed to demonstrate the relationship between SE and operating variables using regression analysis and the model was then verified.It was found that the optimal combination of operating variables for minimum SE is the peripheral speed of 25 m/s,the traverse speed of 70 cm/min,the cut depth of 2 cm and the flow rate of cooling fluid of 100 mL/s.The cut depth and traverse speed were statistically determined as the significant operating variables affecting the SE,respectively.Furthermore,the regression model results reveal that the predictive model has a high applicability for practical applications. 展开更多
关键词 circular diamond sawblades GRANITE specific energy Taguchi approach
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Triple non-invasive diagnostic test for exclusion of common bile ducts stones before laparoscopic cholecystectomy
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作者 Bahram Pourseidi Amir Khorram-Manesh 《World Journal of Gastroenterology》 SCIE CAS CSCD 2007年第43期5745-5749,共5页
AIM: To evaluate the impact of a preoperative "triple non-invasive diagnostic test" for diagnosis and/or exclusion of common bile duct stones. METHODS: All patients with symptomatic gallstone disease, operat... AIM: To evaluate the impact of a preoperative "triple non-invasive diagnostic test" for diagnosis and/or exclusion of common bile duct stones. METHODS: All patients with symptomatic gallstone disease, operated on by laparoscopic cholecystectomy from March 2004 to March 2006 were studied retrospectively. Two hundred patients were included and reviewed by using a triple diagnostic test including: patient's medical history, routine liver function tests and routine ultrasonography. All patients were followed up 2-24 mo after surgery to evaluate the impact of triple diagnostic test. RESULTS: Twenty-five patients were identified to have common bile duct stones. Lack of history of stones, negative laboratory tests and normal ultrasonography alone was proven to exclude common bile duct stones in some patients. However, a combination of these three components (triple diagnostic), was proven to be the most statistically significant test to exclude common bile duct stones in patients with gallstone disease. CONCLUSION: Using a combination of routinely used diagnostic components as triple diagnostic modality would increase the diagnostic accuracy of common bile duct stones preoperatively. This triple non-invasive test is recommended for excluding common bile duct stones and to identify patients in need for other investigations. 展开更多
关键词 Common bile duct stones Laparoscopic cholecystectomy Triple non-invasive diagnostic test
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Elastic-plastic finite element simulation for diamond turning process
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作者 宗文俊 李旦 +3 位作者 孙涛 王洪祥 程凯 董申 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2006年第1期88-93,共6页
Using general commercial software, a coupled thermo-mechanical plane strain larger deformation orthogonal cutting model is developed on the basis of updated Lagrangian formulation in this paper. The workpiece is oxyge... Using general commercial software, a coupled thermo-mechanical plane strain larger deformation orthogonal cutting model is developed on the basis of updated Lagrangian formulation in this paper. The workpiece is oxygen free high conductivity copper (OFHC copper), its flow stress is considered as a function of strain, strain rate and temperature to reflect its realistic changes in physical properties. In order to take into account the cutting edge radius effects of the single crystal diamond tool, rezoning technology is introduced into this simulation model. Diamond turning process is simulated from the initial stage to the steady stage of chip formation, and the distribution of temperature, equivalent stress, residual stress, strain rate and shear angle are obtained. The simulated principal force is compared with published experiment data and they are found to be in good agreement with each other, but poor for thrust force due to no consideration of elastic recovery for machined surface in the elastic-plastic material model. 展开更多
关键词 elastic-plastic FEM SIMULATION diamond turning cutting edge radius
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Rock Cutting Analysis Employing Finite and Discrete Element Methods
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作者 Carla Massignani Carrapatoso Carlos Emmanuel Ribeiro Lautenschlager +1 位作者 Guilherme Lima Righetto Sergio Augusto Barreto da Fontoura and Nelson Inoue 《Journal of Mechanics Engineering and Automation》 2016年第2期100-108,共9页
The petroleum industry has shown great interest in the study of drilling optimization on pre-salt formations given the low rates of penetration observed so far. Rate of penetration is the key to economically drill the... The petroleum industry has shown great interest in the study of drilling optimization on pre-salt formations given the low rates of penetration observed so far. Rate of penetration is the key to economically drill the pre-salt carbonate rock. This work presents the results of numerical modeling through finite element method and discrete element method for single cutter drilling in carbonate samples. The work is relevant to understand the mechanics of drill bit-rock interaction while drilling deep wells and the results were validated with experimental data raised under simulated downhole conditions. The numerical models were carried out under different geometrical configurations, varying the cutter chamfer size and back-rake angles. The forces generated on the cutter are translated into mechanical specific energy as this parameter is often used to measure drilling efficiency. Results indicate that the chamfer size does not change significantly the mechanical specific energy values, characteristic. Results also show there is a significant increase although the cutter aggressiveness is influenced by this geometrical in drilling resistance for larger values of back-rake angle. 展开更多
关键词 Rock cutting discrete element method finite element method single cutter test.
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