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作者： (美)craig walls

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Rock characterization while drilling and application of roof bolter drilling data for evaluation of ground conditions

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Journal of Rock Mechanics and Geotechnical Engineering 2015年第3期7卷 273-281页

作者： Jamal Rostami Sair Kahraman Ali Naeimipour craig Collins Department of Energy and Mineral Engineering Pennsylvania State University Mining Engineering Department Hacettepe University J.H. Fletcher & Co.

Despite recent advances in mine health and safety, roof collapse and instabilities are still the leading causes of injury and fatality in underground mining operations. Improving safety and optimum design of ground support requires good and reliable ground characterization. While many geophysical methods have been developed for ground characterizations, their accuracy is insufficient for customized ground support design of underground workings. The actual measurements on the samples of the roof and wall strata from the exploration boring are reliable but the related holes are far apart, thus unsuitable for design purposes. The best source of information could be the geological back mapping of the roof and walls, but this is disruptive to mining operations, and provided information is only from rock *** of the data obtained from roof bolt drilling can offer a good and reliable source of information that can be used for ground characterization and ground support design and evaluations. This paper offers a brief review of the mine roof characterization methods, followed by introduction and discussion of the roof characterization methods by instrumented roof bolters. A brief overview of the results of the preliminary study and initial testing on an instrumented drill and summary of the suggested improvements are also discussed.

关键词： Roof bolter Rock characterization Three-dimensional(3D) visualization of ground Ground support optimization

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Ultrafast z-scanning for high-efficiency laser micro-machining

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Light(Science & Applications) 2018年第1期7卷 1094-1102页

作者： Ting-Hsuan Chen Romain Fardel craig B Arnold Department of Mechanical and Aerospace Engineering and Princeton Institute for the Science and Technology of MaterialsPrinceton UniversityPrincetonNJ 08544USA

High-throughput laser micro-machining demands precise control of the laser beam position to achieve optimal efficiency,but existing methods can be both time-consuming and *** this paper,we demonstrate a new high-throughput micromachining technique based on rapidly scanning the laser focal point along the optical axis using an acoustically driven variable focal length *** results show that this scanning method enables higher machining rates over a range of defocus distances and that the effect becomes more significant as the laser energy is *** a specific example of silicon,we achieve a nearly threefold increase in the machining rate,while maintaining sharp side walls and a small spot *** method has great potential for improving the micro-machining efficiency of conventional systems and also opens the door to applying laser machining to workpieces with uneven topography that have been traditionally difficult to process.

关键词： high-efficiency micro-machining laser material processing TAG lens ultrafast z-scanning

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柔性聚氨酯泡沫燃烧产物毒性评估(英文)

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消防科学与技术 2007年第5期26卷 476-484页

作者： craig BEYLER Hughes Associates Inc.3610 Commerce DriveSuite 817 BaltimoreMD 21227USA

介绍了对弹性聚氨酯泡沫燃烧产物毒性的相关研究,并对其是否能用于毒性危害分析进行了评估。研究显示,暴露到聚氨酯燃烧产物中的人会导致中毒。窒息气体氮气有效剂量法能有效预测受害人因暴露于聚氨酯燃烧产物而导致的行为能力丧失情况... 详细信息

介绍了对弹性聚氨酯泡沫燃烧产物毒性的相关研究,并对其是否能用于毒性危害分析进行了评估。研究显示,暴露到聚氨酯燃烧产物中的人会导致中毒。窒息气体氮气有效剂量法能有效预测受害人因暴露于聚氨酯燃烧产物而导致的行为能力丧失情况。同时,也证明有效剂量法不能正确预测聚氨酯阴燃时情况。该方法不适用于热分解。研究发现,目前很多经验方法具有很大的局限性,对毒性危害研究造成了很多负面的影响。烟气粒子携带毒物的吸入和传播以及化学合成复杂的毒物,研究和考虑得很少。因此,很有必要对复杂毒性有机体的火灾燃烧产物进行更深入的物理和化学分析研究以及动物模型研究。

关键词：燃烧毒性燃烧产物

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英格兰东北部17型脊髓小脑性共济失调的最低患病率

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世界核心医学期刊文摘（神经病学分册） 2006年第3期2卷 25-25页

作者： craig K. Keers S.M. walls T.J. P.F. Chinnery 王孝文 Neurology Medical School Framlington Place Newcastle upon Tyne NE2 4HH United Kingdom

Objective: To determine the minimum prevalence of spinocerebellar ataxia type 17 (SCA17) in the north east of England. Patients and methods: A defined region containing 2,516,500 individuals with 192 families with undiagnosed ataxia, 90 patients with a Huntington’s disease-like phenotype and 292 controls. The number of (CAG/CAA)n repeats in the SCA17/TBP gene was determined by fluorescent PCR and sequenced in affected individuals. Results: The mean repeat size for 584 control alleles was 34 (S.D. = 3.58), ranging from 25 to 40. Two index cases had larger alleles with repeat lengths greater than the control range. Affected family members presented in adult life with ataxia followed by extrapyramidal features and cognitive impairment. In one family 44 repeats were associated with a younger age of onset than has been previously described. Conclusions: The minimum prevalence of SCA17 in the north east of England was 0.16/100,000 (upper 95%confidence interval 0.31/100,000).

关键词：共济失调亨廷顿病认知功能损害重复次数锥体外系

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