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油气井测试的井下远程遥测方式分析 被引量:22
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作者 李成 丁天怀 《油气井测试》 EI 2005年第6期34-37,共4页
准确完整的获得井下待测地层数据有利于全面评价油藏特性,为此研究了地面直读、井 下存储、存储直读和无线遥测试井方式。综合比较各种试井方式的功能,分析了无线遥测和存储直 读式遥测的实现原理、技术特征,以及二者融合的优越性。结... 准确完整的获得井下待测地层数据有利于全面评价油藏特性,为此研究了地面直读、井 下存储、存储直读和无线遥测试井方式。综合比较各种试井方式的功能,分析了无线遥测和存储直 读式遥测的实现原理、技术特征,以及二者融合的优越性。结合井下恶劣条件和油气井测试现状, 选择钻杆或油管为研究对象,纵波为传输载体,提出基于井下无缆声传输技术和存储直读试井两者 相结合的遥测方式,可实现全通径远距离非接触信号传输。论述了声传输的信道特性、影响因素和 信号检测方法。 展开更多
关键词 井下 油气井测试 远程遥测 存储直读 声传输
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产科快速反应团队的建立和演练 被引量:14
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作者 王晓怡 陈晴晴 陈敦金 《中国实用妇科与产科杂志》 CAS CSCD 北大核心 2019年第9期996-999,共4页
鉴于产科病情突变、易变、多变,在孕产妇病情发展初期时即采取有效的处置措施,而不是待其病情恶化后才进行复苏抢救的快速反应团队(RRT)尤为重要。产科RRT的建立需要医院、产科及其他科室的共同支持。RRT建成后的培训、演练及考核也需... 鉴于产科病情突变、易变、多变,在孕产妇病情发展初期时即采取有效的处置措施,而不是待其病情恶化后才进行复苏抢救的快速反应团队(RRT)尤为重要。产科RRT的建立需要医院、产科及其他科室的共同支持。RRT建成后的培训、演练及考核也需定期开展,使RRT团队能力不断提升。 展开更多
关键词 快速反应团队 建立 演练 预警标准
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青藏铁路冻土爆破开挖技术 被引量:9
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作者 杨年华 张志毅 +1 位作者 傅洪贤 张翠兵 《中国铁道科学》 EI CAS CSCD 北大核心 2005年第3期11-15,共5页
青藏铁路冻土爆破开挖必须解决高原、冻土、环保三大技术难题。针对青藏线多年冻土区的地质结构特征和对爆破器材的要求,在青藏铁路冻土爆破中,应尽可能采用机械化装药和高威力炸药。现场试验证明在暖季爆破可选用普通销铵炸药和乳化炸... 青藏铁路冻土爆破开挖必须解决高原、冻土、环保三大技术难题。针对青藏线多年冻土区的地质结构特征和对爆破器材的要求,在青藏铁路冻土爆破中,应尽可能采用机械化装药和高威力炸药。现场试验证明在暖季爆破可选用普通销铵炸药和乳化炸药,在寒季拟选用防冻、抗水性炸药。钻孔机械选型建议为:钻孔深度不超过2 0m的浅层开挖爆破可选择麻花钻;钻孔深度2~7m的中深层开挖爆破可选择冲击钻,并可在含碎石的冻土中穿凿钻孔;开挖深度大于5m,且开挖方量比较集中的工点,可选择牙轮冲击回转式钻机。通过冻土中钻孔扩壶爆破试验和深孔爆破试验,青藏高原多年冻土应采用弱松动爆破,炸药单耗一般控制在0 25~0 35kg·m3,一次爆破规模限定在当天爆破当天挖运的方量。 展开更多
关键词 青藏铁路 冻土 爆破 爆破参数 钻孔
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金属离子注入钢表面摩擦学特性及应用研究 被引量:8
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作者 张通和 吴瑜光 马芙蓉 《微细加工技术》 2002年第1期18-21,39,共5页
着重介绍了改善钢表面摩擦学特性的方法和提高离子束加工效率的途径。这项金属离子注入技术在工业生产发展中正发挥着重要的作用 。
关键词 金属离子注入 钢表面 摩察学 工业应用 钻头
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高速微小孔钻头动态应力特性 被引量:3
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作者 TRAORE M Magara 裴永臣 谭庆昌 《吉林大学学报(工学版)》 EI CAS CSCD 北大核心 2005年第6期606-612,共7页
针对微小钻头工作时容易折断的问题,依据转子动力学理论,利用Timoshenko梁-轴单元,建立了微孔钻床主轴系统的动力学模型。该模型考虑了钻头在切削时主轴-钻夹头-微钻头系统的偏心、钻削轴向力、系统转动惯性力、陀螺力矩和轴承等因素对... 针对微小钻头工作时容易折断的问题,依据转子动力学理论,利用Timoshenko梁-轴单元,建立了微孔钻床主轴系统的动力学模型。该模型考虑了钻头在切削时主轴-钻夹头-微钻头系统的偏心、钻削轴向力、系统转动惯性力、陀螺力矩和轴承等因素对微弯曲变形的影响。利用该模型确定了钻头的危险截面,分析了钻头夹持长度、轴承刚度、轴承阻尼、主轴转速、系统偏心、钻削轴向力以及钻削扭矩等因素对危险截面应力的影响。最后提出了避免微小钻头折断的措施,可用于指导微小孔钻床的设计和生产实践。 展开更多
关键词 机械设计 钻头 钻床 应力分析 微小钻头 动态应力 转子动力学 微小孔钻床
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正反气动冲击机构系统仿真分析及结构优化 被引量:6
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作者 王四一 孙友宏 +4 位作者 王清岩 赵研 赵江鹏 王传留 张武 《吉林大学学报(地球科学版)》 EI CAS CSCD 北大核心 2011年第S1期242-247,共6页
基于虚拟样机技术,利用SimulationX软件对应用于RPH系列双向气动冲击矛的正反气动冲击机构建立了系统仿真模型,在模型上进行了一系列的仿真模拟,得到了冲击机构工作参数的变化过程,比如活塞的冲击速度曲线、冲击力曲线等,揭示了其内部... 基于虚拟样机技术,利用SimulationX软件对应用于RPH系列双向气动冲击矛的正反气动冲击机构建立了系统仿真模型,在模型上进行了一系列的仿真模拟,得到了冲击机构工作参数的变化过程,比如活塞的冲击速度曲线、冲击力曲线等,揭示了其内部结构的工作状态。通过仿真模拟分析,找到了影响冲击机构性能的主要结构参数。通过一组模拟,选取了影响冲击机构性能的主要参数的最恰当值,对设计进行了优化。 展开更多
关键词 虚拟样机技术 正反气动冲击机构 系统仿真 结构优化 钻头
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教学与科技整合:在线成人汉语口语入门课程设计 被引量:6
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作者 吴英成 邱利军 《国际汉语教学研究》 2019年第2期31-38,共8页
随着移动互联网的兴起和智能手机的普及,在线课程通过再中介化、分散化、非物质化三股数字化驱动力遍布世界各地。国际汉语教学界应顺势而为,将在线平台打造成全球汉语教室,利用前沿信息和通信技术,与教育产业深度结合,让汉语学习者能... 随着移动互联网的兴起和智能手机的普及,在线课程通过再中介化、分散化、非物质化三股数字化驱动力遍布世界各地。国际汉语教学界应顺势而为,将在线平台打造成全球汉语教室,利用前沿信息和通信技术,与教育产业深度结合,让汉语学习者能够随时随地进行自主学习,开启数字化教育新篇章。在课程理念方面,应以口语为主位,以语音、语法、词汇、文化为四大核心构件,以外语教学作为培养双语人才的模式,以5C目标及其11项标准作为与汉语世界接轨的语言学习目标,以语言知行兼容作为教学指南,以个人化按需学习配套模块作为个人学习规划总蓝图,以实时在线专业咨询与技能指导作为后台支援。在教材设计方面,应以口语发展、发音基础、汉语导读三个既独立自主又相互联系的元件作为在线汉语口语入门课程的学习路径,以超量学习策略让零起点成人汉语学习者通过精熟学习七步法掌握听说技巧,以替换、转换、回应、扩展、组合五大操练法提升语言流利度和实现语言自动化,以听力理解、口语表达两大应用练习完成指定语言学习任务。在课程研发方面,应建立课程研发新模式:设立内部课程发展处,培养在线课程数字化市场人才;成立众包课程发展处,广邀世界各地国际汉语教学同行共创本土化汉语教材,并提供后台学习支援。 展开更多
关键词 在线平台 汉语口语入门课程 个人化按需学习 超量学习 模仿 操练
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Strategic planning and designing of a hospital disaster manual in a tertiary care, teaching, research and referral institute in India 被引量:3
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作者 Shweta Talati Prateek Bhatia +2 位作者 Ashok Kumar A.K.Gupta Col.D Ojha 《World Journal of Emergency Medicine》 CAS 2014年第1期35-41,共7页
BACKGROUND: As per the "Disaster Management Act, 2005" of India, it is mandatory for government hospitals in India to prepare a disaster plan. This study aimed to prepare a disaster manual of a 1 900 bed ter... BACKGROUND: As per the "Disaster Management Act, 2005" of India, it is mandatory for government hospitals in India to prepare a disaster plan. This study aimed to prepare a disaster manual of a 1 900 bed tertiary care hospital, in consultation and involvement of all concerned stakeholders.METHODS: A committee of members from hospital administration, clinical, diagnostic and supportive departments worked on an initial document prepared according to the Act and gave their inputs to frame a final disaster manual.RESULTS: The prepared departmental standard operating procedures involved 116 people(doctors and paramedical staff), and were then synchronized, in 12 committee meetings, to produce the final hospital disaster manual.CONCLUSIONS: The present disaster manual is one of the few comprehensive plans prepared by the stakeholders of a government hospital in India, who themselves form a part of the disaster response team. It also helped in co-ordinated conduction of mock drills. 展开更多
关键词 Disaster Management Act Disaster manual Hospital administration STAKEHOLDERS Mock drills
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大型立辊深孔加工工艺的优化
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作者 马绍华 《酒钢科技》 2024年第2期32-35,49,共5页
深孔加工的特点是工艺复杂、难度大。本文从工艺中的难点切入,结合现有深孔加工的案例,提出在卧式镗床上加工,改进普通麻花钻的结构,优化加工工艺参数,细化操作手段,为高效稳定的深孔加工提供借鉴作用。
关键词 深孔加工 钻头 钻杆 卧式镗床
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Research on the emergency response mechanism of emergencies in student management in private colleges and universities
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作者 Xiaomin Hu 《Journal of Social Science Development Research》 2024年第3期82-89,共8页
With the advancement of the popularization of higher education in China,the development of private higher education institutions has been rapid and dynamic.However,various unexpected events have become increasingly fr... With the advancement of the popularization of higher education in China,the development of private higher education institutions has been rapid and dynamic.However,various unexpected events have become increasingly frequent,bringing negative impacts to schools and even threatening their survival and development.Therefore,ensuring the harmonious and stable development of private higher education institutions and improving their emergency management mechanisms for unexpected events is an urgent task.This paper analyzes the relevant issues and causes regarding the management of unexpected events in private higher education institutions from six aspects:emergency awareness,organizational structure,plan formulation,training and drills,supervision and evaluation,and post-incident handling and accountability.Based on these analyses,the paper further proposes corresponding strategies from three levels:prevention,response,and recovery,aiming to provide theoretical references of value for enhancing the governance system and capacity of private higher education institutions in managing unexpected events. 展开更多
关键词 Crisis awareness Emergency drills Security and stability
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Effects of QD2R Numeracy Enhancement Strategy on the Mathematics Performance of Grade 10 Students
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作者 Joshelle N.Abiog 《Journal of Contemporary Educational Research》 2024年第2期256-271,共16页
Learning mathematics requires an effective and strategic teaching approach.This study aimed to assess the mathematics performance of the learners with the implementation of the numeracy enhancement strategy QD2R(Quest... Learning mathematics requires an effective and strategic teaching approach.This study aimed to assess the mathematics performance of the learners with the implementation of the numeracy enhancement strategy QD2R(Questions,Drills,Repetition,and Recitation)and to propose a strategy implementation plan to elevate their performances.This study employed the use of a quasi-experimental research design,purposive sampling with 70 Grade 10 students of Lian National High School who were distributed equally to control and treatment groups.The pre-test and post-test results were statistically analyzed using independent and paired sample t-tests,and a survey questionnaire was examined by getting the mean and standard deviation.The results indicated that better performance was achieved by the students from the treatment group compared to the students from the control group,as revealed by the Mean Percentage Score(MPS)results,mean scores,and P values of their pre-test and post-test scores.The learners’perception of the implementation of this strategy was to a great extent,wherein it was perceived to be more helpful in concepts related to understanding the lesson compared to concepts related to developing their attitude and skills.Moreover,the proposed implementation plan of numeracy enhancement strategy QD2R had three expected outcomes:elevated understanding and performance in mathematics lessons;modified strategy to focus on the development of attitude and skills towards mathematics;and refined and well-implemented QD2R strategy in teaching mathematics.Relative to these expected outcomes,appropriate measures,timeframe,and resources of each were comprehensively formulated. 展开更多
关键词 Questions drills Repetition Recitation Numeracy enhancement strategy PERFORMANCE MATHEMATICS
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气体局部反循环电动机械冰钻技术 被引量:4
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作者 胡正毅 达拉拉伊.帕维尔 +3 位作者 曹品鲁 薛军 郑治川 于达慧 《吉林大学学报(地球科学版)》 EI CAS CSCD 北大核心 2012年第S3期374-378,共5页
针对南极内陆上部的积雪层较松软,裂隙、空隙发育,常规钻进易导致冲洗液漏失等技术难题,设计了低能耗、轻便快捷的气体局部反循环电动机械取心钻具,对反循环所需的气体流量进行了计算分析;在此基础上建立了模拟试验台,并对反循环气体流... 针对南极内陆上部的积雪层较松软,裂隙、空隙发育,常规钻进易导致冲洗液漏失等技术难题,设计了低能耗、轻便快捷的气体局部反循环电动机械取心钻具,对反循环所需的气体流量进行了计算分析;在此基础上建立了模拟试验台,并对反循环气体流量进行了实验测试。结果表明:当气体的流量不小于70 L/s时,气体在管长3~4 m、管径为110 mm的模拟管中能够形成局部反循环,并可以抽吸直径为2mm左右的冰屑。 展开更多
关键词 气体反循环 浅层冰钻 电动机械取心钻具 钻具
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双面回油型液压凿岩机空穴及气蚀机理 被引量:1
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作者 耿晓光 马飞 +2 位作者 周志鸿 郭荣 马威 《煤炭学报》 EI CAS CSCD 北大核心 2016年第S2期563-570,共8页
具有双面回油型冲击机构的液压凿岩机,其能量利用率高,但活塞回程制动阶段的前腔负压常常造成活塞和前导向套的严重气蚀,影响了凿岩机的正常使用。阐明了双面回油型冲击机构的工作原理,考虑油液压缩、油液泄漏和活塞的撞击回弹等因素,... 具有双面回油型冲击机构的液压凿岩机,其能量利用率高,但活塞回程制动阶段的前腔负压常常造成活塞和前导向套的严重气蚀,影响了凿岩机的正常使用。阐明了双面回油型冲击机构的工作原理,考虑油液压缩、油液泄漏和活塞的撞击回弹等因素,建立了冲击机构的数学模型,并进行数值仿真。通过凿岩机机理实验,测试了活塞前、后腔压力和冲击频率,得到了活塞的冲程末速度。比较实验与仿真结果,验证数学模型的正确性。在此基础上,通过仿真获得了阀芯与活塞的位移曲线和速度曲线,确定了阀芯开始换向、经历负开口区间以及换向完成的准确时间点。给出了活塞前、后腔和左、右阀腔的压力变化规律,揭示了前腔空穴的产生机理。为此设计并加装了回油蓄能器,分析了不同的充气压力对前腔空穴的影响。仿真结果表明,回油蓄能器能够在一定程度上改善前腔负压问题,且在0 MPa的充气压力下,效果最佳,负压的持续时间将减半。 展开更多
关键词 液压凿岩机 双面回油型冲击机构 活塞回弹 机理实验 空穴
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辐射环境安全事故的应急准备和演练 被引量:3
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作者 曹凤琦 黄晓华 +1 位作者 杨斌 姚颖 《环境监控与预警》 2011年第4期6-8,共3页
核技术的广泛应用给人类带来巨大利益的同时,也不可避免地产生一定程度的危害。结合辐射环境安全事故的特点,从事故类型、应急组织、应急响应准备、应急响应处置、应急演练的开展等方面详细阐述了如何开展辐射环境安全事故应急准备和演... 核技术的广泛应用给人类带来巨大利益的同时,也不可避免地产生一定程度的危害。结合辐射环境安全事故的特点,从事故类型、应急组织、应急响应准备、应急响应处置、应急演练的开展等方面详细阐述了如何开展辐射环境安全事故应急准备和演练,以提高辐射应急处置能力和水平。 展开更多
关键词 辐射环境 事故 应急 演练
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美国印第安那大学(布鲁明顿)中文教学特色 被引量:2
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作者 王群 褚智歆 《暨南大学华文学院学报》 CSSCI 2009年第3期1-4,共4页
美国印第安那大学(布鲁明顿)东亚语言与文化系(Department of East Asian Languages&Cultures,文中简称EALC)的中文项目开展多年,影响广泛,不断自我完善的教学管理和强调交际的小班教学,是其中文教学的两大特色。本文首先通过对教... 美国印第安那大学(布鲁明顿)东亚语言与文化系(Department of East Asian Languages&Cultures,文中简称EALC)的中文项目开展多年,影响广泛,不断自我完善的教学管理和强调交际的小班教学,是其中文教学的两大特色。本文首先通过对教学管理中选择教材、选拔助教、编订教案三个环节的简介,说明其如何保证教学管理系统的完善性和循环性;然后通过对小班课堂教学中生词练习、句型练习、语言活动的描述,介绍其如何利用情境假设进行交际练习的具体操作过程。本文旨在介绍海外汉语教学经验,服务对外汉语教学与研究工作。 展开更多
关键词 情境 小班课 助教 教学管理 美国印第安那大学东亚语言与文化系
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谈普通高等院校军事课程队列训练 被引量:3
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作者 曾海明 张亮 《武警学院学报》 2009年第7期78-79,82,共3页
队列是随冷兵器时代两军对垒应运而生的,与军人日常生活及战斗行动密不可分。自上世纪九十年代在高级中学和普通高等院校开展军训以来,很多注重或需要对外宣传自身形象的事业企业单位也进行队列训练。队列训练应该从军人职业行为特点,... 队列是随冷兵器时代两军对垒应运而生的,与军人日常生活及战斗行动密不可分。自上世纪九十年代在高级中学和普通高等院校开展军训以来,很多注重或需要对外宣传自身形象的事业企业单位也进行队列训练。队列训练应该从军人职业行为特点,从受训者形成优良意志品质等方面去认识,在科学组训上下功夫。 展开更多
关键词 队列训练 战术素养 战斗精神 素质教育
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Assessment of Cutting Parameters Influencing on Thrust Force and Torque during Drilling Particulate Filled Glass Fabric Reinforced Epoxy Composites
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作者 Bhadrabasol Revappa Raju Bheemappa Suresha +1 位作者 Ragera Parameshwarappa Swamy Bannangadi Swamy Gowda Kanthraju 《Journal of Minerals and Materials Characterization and Engineering》 2013年第3期101-109,共9页
Drilling is indispensable process and it cannot be avoided for joining composite structures used in various engineering applications. In this research article, the influence of drilling parameters on thrust force and ... Drilling is indispensable process and it cannot be avoided for joining composite structures used in various engineering applications. In this research article, the influence of drilling parameters on thrust force and torque of silica (SiO2) and alumina (Al2O3) filled into glass fabric reinforced epoxy (G-E) composites are analyzed. Drilling experiments are conducted on these composite materials using BATLIBOI make radial drilling machine. Two different drill bits (HSS and cemented carbide) are used for the experimentation. The influence of drilling parameters like cutting speed and feed on thrust force and torque on drilling of particulate filled G-E composites has been carried out. The experimental results indicated that the thrust force and torque were increased with increasing feed and cutting speed for all the composites tested. Further, it is observed that the carbide drill performed better than HSS drill during drilling of particulate filled G-E composites. The drilled surfaces are examined using scanning electron microscopy (SEM) and damage mechanisms are discussed. 展开更多
关键词 PARTICULATE FILLED Glass-Epoxy Composites drillING THRUST Force and Torque HSS and CARBIDE drills
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Major Approaches on the Piezoelectric Device, Drills and Saws to Orthognathic Surgery: A Systematic Review
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作者 Diego César Marques Vanessa Gabriela Gonzáles Pinto +5 位作者 Rogério Luiz de Araújo Vian Regis Manzini Leandro Aparecido Irrazabal Priscilla Janaína de Lima Borelli Bovo Idiberto José Zotarelli Filho Elias Naim Kassis 《Health》 2019年第6期783-791,共9页
Introduction: The incidence of lesions of sensory and motor nerves associated with oral and maxillofacial surgery is often underestimated, representing around 32.0% of all lesions, and orthognathic surgery contributes... Introduction: The incidence of lesions of sensory and motor nerves associated with oral and maxillofacial surgery is often underestimated, representing around 32.0% of all lesions, and orthognathic surgery contributes 12.3% to these lesions. Thus, the use of piezosurgery (PiZCi) has been indicated in several procedures within oral and maxillofacial surgery due to a number of advantages over conventional drill and saw techniques. Objective: to analyze the main literature on the use of the piezoelectric device in relation to the use of drills and to orthognathic surgery in dentistry. Methods: A total of 41 articles were found involving Orthognathic Surgery, Piezoelectric Device, Drills Device, Saws Device, and Efficiency. Initially, it was held the exclusion existing title and duplications following the interest described this work. After this process, the summaries were evaluated, and a new exclusion was held. 29 articles were included and discussed in this study. Initially, the keywords were determined by searching the DeCS tool (Descriptors in Health Sciences, BIREME base) and later verified and validated by MeSh system (Medical Subject Headings, the US National Library of Medicine). Results and conclusion: It was concluded that the piezoelectric device has excelled with an effective surgical technique, being able to be indicated in the most diverse areas of the oral surgery, providing accurate, clean and minimally traumatic osteotomies for the soft tissues, intraoperative bleeding, when compared to conventional surgery using drills and/or saws. 展开更多
关键词 ORTHOGNATHIC SURGERY PIEZOELECTRIC DEVICE drills DEVICE SAWS DEVICE Efficiency
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采用岩心钻机改装成大口径工程钻机应注意的问题
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作者 王需贞 陈逸 《探矿工程》 1994年第5期23-25,28,共4页
岩心钻机改装成大口径工程钻机已取得成功,但在实际使用中,圆锥齿轮经常损坏。分析了影响钻机上圆锥齿轮使用寿命的因素,并提出了改进措施。
关键词 岩心钻机 改装 工程钻机 圆锥齿轮
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A Review: Embedding a Simulation Training Program in Labor and Delivery to Improve Healthcare Quality, Clinical Outcomes, and Patient Satisfaction
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作者 Dana K. Bryant 《Open Journal of Obstetrics and Gynecology》 2019年第9期1226-1249,共24页
In response to maternal deaths being three-fold higher for black women than other races in New York City, Governor Andrew M. Cuomo created a taskforce which met for a year. In March 2019, the taskforce published ten r... In response to maternal deaths being three-fold higher for black women than other races in New York City, Governor Andrew M. Cuomo created a taskforce which met for a year. In March 2019, the taskforce published ten recommendations to address the current healthcare disparities. The taskforce recommended utilizing medical simulation training to improve skills and communication. Peer-reviewed literature was explored for evidentiary support for embedding a simulation program in a NYC public hospital. In addition, obstacles to and advantages of in-situ simulation programs were discussed. Steps for garnering executive leadership support, improving teamwork, defining outcome measures, and identifying beneficiaries of in-situ simulation programs were explored. 展开更多
关键词 Embedded SIMULATION POSTPARTUM Hemorrhage drills INTERDISCIPLINARY Teaching TEAMWORK in OBSTETRICS Qualitative and Quantitative Improvements in OBSTETRICAL Outcomes
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