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MWD井下辅助司钻
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作者 贾敏华 mark hutchinson 《国外石油机械》 1997年第1期11-13,21,共4页
介绍一种MWD井下辅助司钻。利用这一装置,可测量钻井过程中钻头附近的钻井力和运动,并在钻台显示器上实时、直观地显示有关信息和建议,使司钻可以更恰当、更及时地对钻井控制装置作出调整。这种工具主要用于钻井性能方面,同时也提高了... 介绍一种MWD井下辅助司钻。利用这一装置,可测量钻井过程中钻头附近的钻井力和运动,并在钻台显示器上实时、直观地显示有关信息和建议,使司钻可以更恰当、更及时地对钻井控制装置作出调整。这种工具主要用于钻井性能方面,同时也提高了钻井操作的安全性。 展开更多
关键词 钻井参数 MWD 随钻测量系统
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Preseason elimination impact on anterior cruciate ligament injury in the national football league
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作者 Michael Patetta Benjamin Mayo +3 位作者 Omar Zaki Martini Breanna Sullivan Leonard Onsen mark hutchinson 《World Journal of Orthopedics》 2021年第11期833-841,共9页
BACKGROUND Anterior cruciate ligament(ACL)injuries represent detrimental injuries in the National Football League(NFL).A significant portion of these injuries often occur in preseason exhibitions.The Coronavirus disea... BACKGROUND Anterior cruciate ligament(ACL)injuries represent detrimental injuries in the National Football League(NFL).A significant portion of these injuries often occur in preseason exhibitions.The Coronavirus disease 2019 pandemic presented a unique disruption to preseason NFL football with the cancelation of all preseason games.AIM To compare the incidence of ACL tears through the first eight weeks of the NFL season in 2020 to the mean incidence over the previous 5 seasons(2015-2019)and determine if there was any change in incidence with the elimination of the preseason.METHODS NFL players who suffered ACL tears during the preseason and first eight weeks of the NFL season from 2015-2020 were identified.The number of ACL injuries for the 2015-2019 seasons was compared to the 2020 season for four different timeframes.For each analysis,the cumulative number of ACL injuries to that time point was used to calculate the percent difference for descriptive analysis.Additionally,the number of teams with at least one player suffering an ACL tear were identified and compared using Chi-Squared testing.Finally,a cumulative relative risk was calculated for each week played.RESULTS There were 14 ACL tears through the first four games of the 2020 season,a 118.8%(14 vs 6.4)increase in comparison to the 5-year average over the first 4 regular season weeks of 2015-2019.However,when accounting for injuries occurring during the preseason from 2015-2019,there were 18.6%(14 vs 17.2)fewer total ACL injuries through regular season week 4 with no significant difference in percentage of teams impacted when these preseason injuries were accounted for P=0.394.Results were similar(19 vs 17.2)over 8 total games played(whether regular season or preseason),and over 8 regular season games(P=0.196,P=0.600).CONCLUSION The elimination of the NFL preseason resulted in a higher rate of injuries during the first 4 games of the regular season.However,these increases are offset by the injuries typically sustained during the preseason.This suggests there may be front-loading of injuries over the course of an NFL season,such that players may be more prone to injury when the intensity of play suddenly increases,whether in the preseason or regular season. 展开更多
关键词 Anterior cruciate ligament National football league Player safety Ligamentous injury Preseason COVID-19
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非开挖设计和施工中的风险管理
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作者 Kimberlie Staheli mark hutchinson +1 位作者 Brad Moore 田青 《非开挖技术》 2017年第5期1-7,共7页
非开挖风险已成为许多非开挖设计中的焦点。成功的非开挖设计不仅对一个场地的不同非开挖方法的能力和特点进行评估,它还会对一个项目的非开挖风险进行准确评估。这种评估是与业主共同工作的重点,以在设计中确保能够了解风险的清晰性... 非开挖风险已成为许多非开挖设计中的焦点。成功的非开挖设计不仅对一个场地的不同非开挖方法的能力和特点进行评估,它还会对一个项目的非开挖风险进行准确评估。这种评估是与业主共同工作的重点,以在设计中确保能够了解风险的清晰性以及施工中的可能性。业主经常在能够做到最小化或甚至消除这些风险的设计特征和规范规定方面对降低风险进行重大投资。虽然我们看到业主愿意为降低风险而投资的趋势有所增加,但我们发现,在施工中对这些重要的设计特征进行放宽也出现了同样令人不安的趋势。通常这是由于设计团队和施工管理团队之间的沟通出发点产生了问题,导致某些重要的特定特征没有立即得到识别。另一个原因是承包商拒绝遵守被视为“额外的步骤”的规定要求,并且因为对控制承包商的手段和方法、“拥有”他们的施工绩效或承担额外费用、与承包商意见不一而产生执行规范的犹豫。本文将讨论设计中包含的、但在施工过程和产生的影响中不能有效实施的风险管理策略,本文还将分享一些经验教训及避免这些问题产生的策略。 展开更多
关键词 非开挖 风险管理 风险应对策略
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