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Effects of Tube Depth and Infusion Rate of Continuous Humidification by Endotracheal Intubation on Humidification Effect
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作者 Hui Sun Dan Li +1 位作者 Wan Luo Lin Feng 《Open Journal of Nursing》 2017年第1期123-127,共5页
Objective: To investigate the continuous humidification tube insertion depth of endotracheal intubation and the flow rate of the wetting effect. Methods: From October 2008 to May 2010, among 132 patients of oral and m... Objective: To investigate the continuous humidification tube insertion depth of endotracheal intubation and the flow rate of the wetting effect. Methods: From October 2008 to May 2010, among 132 patients of oral and maxillofacial surgery with tracheal intubation, continuous infusion can be adjusted to the wet method;according to the wet pipe, insertion depth of the flow rate is divided into four groups, by four different depths and velocities of the wetting effect, to be analyzed. Results: B group was significantly lower than other groups satisfied with indicators of four significantly different effects of humidification. Conclusion: When continuous humidification tube insertion depth of endotracheal intubation is 10 - 12 cm, and flow rate is 15 - 20 ml/h, the wetting effect will achieve greater satisfaction. 展开更多
关键词 INTUBATION Continuous HUMIDIFICATION tube depth INFUSION Rate HUMIDIFICATION EFFECT
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Analysis of Fluid Flow and Optimization of Tubing Depth in Deep Shale Gas Wells
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作者 Sheng Ju Jie Liu 《Fluid Dynamics & Materials Processing》 2025年第3期529-542,共14页
As shale gas technology has advanced,the horizontal well fracturing model has seen widespread use,leading to substantial improvements in industrial gas output from shale gas wells.Nevertheless,a swift decline in the p... As shale gas technology has advanced,the horizontal well fracturing model has seen widespread use,leading to substantial improvements in industrial gas output from shale gas wells.Nevertheless,a swift decline in the productivity of individual wells remains a challenge that must be addressed throughout the development process.In this study,gas wells with two different wellbore trajectory structures are considered,and the OLGA software is exploited to perform transient calculations on various tubing depth models.The results can be articulated as follows.In terms of flow patterns:for the deep well A1(upward-buckled),slug flow occurs in the Kick-off Point position and above;for the deep well B1(downward-inclined),slug flow only occurs in the horizontal section.Wells with downward-inclined horizontal sections are more prone to liquid accumulation issues.In terms of comparison to conventional wells,it is shown that deep shale gas wells have longer normal production durations and experience liquid accumulation later than conventional wells.With regard to optimal tubing placement:for well A1(upward-buckled),it is recommended to place tubing at the Kick-off Point position;for well B1(downward-inclined),it is recommended to place tubing at the lower heel of the horizontal section.Finally,in terms of production performance:well A1(upward-buckled)outperforms well B1(downward-inclined)in terms of production and fluid accumulation.In particular,the deep well A1 is 1.94 times more productive and 1.3 times longer to produce than conventional wells.Deep well B1 is 1.87 times more productive and 1.34 times longer than conventional wells. 展开更多
关键词 Transient calculation optimal tubing depth liquid accumulation gas wells deep shale gas
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Weak correlation of flower color and nectar-tube depth in temperate grasslands 被引量:1
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作者 Julia Binkenstein Martina Stang +1 位作者 Julien P.Renoult H.Martin Schaefer 《Journal of Plant Ecology》 SCIE CSCD 2017年第2期397-405,共9页
Aims Nectar is one of the most common floral rewards offered to pol-linators by plants.Depending on the plant species,nectar is offered openly or in tubes of various lengths restricting accessibility of this resource ... Aims Nectar is one of the most common floral rewards offered to pol-linators by plants.Depending on the plant species,nectar is offered openly or in tubes of various lengths restricting accessibility of this resource for flower visitors with short mouthparts.if attract-ing pollinators that match floral morphology increases pollination efficiency,flowers could profit from signaling nectar-tube depth to pollinators.Since flower colors are important signals in plant-pol-linator communication,we investigated whether and which differ-ent chromatic or achromatic aspects of flower color might indicate nectar-tube depth or whether flower colors facilitate the differen-tiation between flowers with long nectar tubes by means of high chromatic uniqueness.Methods To this end,we collected flower reflectance spectra of 135 grassland plant species.We analyzed flower colors as raw reflectance spectra in principal component analysis(PCA)and in the color space of honeybees.Important Findings The correlation between flower colors and tube depths was weak.From the bee’s point of view,blue flowers had on average deeper tubes than green,blue-green and UV-green flowers potentially allow-ing insects to predict tube depths based on blue color.Spectral purity did not correlate with nectar-tube depth,nor did the chromatic uniqueness of flower colors in the honeybee color space.Dominant wavelength showed a significant but very weak correlation with tube depth.The achromatic green contrast decreased with increasing tube depth as did brightness;thus deep tubes were less conspicuous than shallow tubes.Chromatic components resulting from PCA did not or only slightly correlate with tube depth.Our results illustrate that flower colors may have a certain potential to indicate tube depth,i.e.nectar accessibility,from a bee’s perspective. 展开更多
关键词 VISION pollination efficiency plant-animal interaction NECTAR tube depth
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The Influence of Notch Depth on the Response of Local Sharp-Notched Circular Tubes under Cyclic Bending
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作者 Kuo-Long Lee Ching-Hsun Meng Wen-Fung Pan 《Journal of Applied Mathematics and Physics》 2014年第6期335-341,共7页
In this paper, the mechanical behavior and buckling failure of SUS304 stainless steel tubes with different local sharp-notched depths subjected to cyclic bending were experimentally investigated. It can be seen that t... In this paper, the mechanical behavior and buckling failure of SUS304 stainless steel tubes with different local sharp-notched depths subjected to cyclic bending were experimentally investigated. It can be seen that the experimental moment-curvature relationship exhibits cyclic hardening and becomes a steady loop after a few cycles. However, the experimental ovalization-curvature relationship exhibits an increasing and ratcheting manner with the number of the bending cycles. In addition, higher notch depth of a tube leads to a more severe unsymmetrical trend of the ovalization-curvature relationship. It has been observed that the notch depth has almost no influence on the moment-curvature relationship. But, it has a strong influence on the ovalization-curvature relationship. Finally, the theoretical model proposed by Kyriakides and Shaw [1] was used in this study for simulating the controlled curvature-number of cycles to produce buckling relationship. Through comparison with the experimental data, the theoretical model can properly simulate the experimental 展开更多
关键词 Circular tube LOCAL SHARP NOTCH NOTCH depth CYCLIC BENDING
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Novel Formula for Calculation of the Optimal Insertion Depth for Cuffed Endotracheal Tubes in Pediatric Major Surgery
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作者 Mao Kinoshita Kazuma Hayase +3 位作者 Mizuki Bando Naofumi Kawai Masaru Shimizu Masayuki Shibasaki 《Open Journal of Anesthesiology》 2019年第3期42-50,共9页
Background: Accurate determination of the optimal insertion depth of a pediatric endotracheal tube (ETT) is quite important. The aim of this study was to create an easily available formula that can be used to determin... Background: Accurate determination of the optimal insertion depth of a pediatric endotracheal tube (ETT) is quite important. The aim of this study was to create an easily available formula that can be used to determine the optimal insertion depth for a cuffed ETT even without depth marking with clear definitions of the upper and lower limits for the tip of ETT in the trachea in clinical practice. Methods: Eighty children under 12 years of age were enrolled. The depth marking of the cuffed ETT was placed at the vocal cords and both lungs were then auscultated using a stethoscope. The upper limit was radiographically defined as the position of the tip of the cuffed ETT being between the clavicles. The lower limit was defined as a distance of 5 mm above the carina. The relationship between the insertion depth and patient characteristics was analyzed to create a formula for optimal ETT insertion depth. Results: Sixty-nine ETTs were optimally placed in the trachea. There were good correlations between the optimal insertion depth of ETTs and patients characteristics (height (R = 0.92);BSA (R = 0.92);weight (R = 0.91);age (R = 0.88)). Using these patient characteristics, we created the following three formulas for calculation of the optimal insertion depth for pediatric cuffed ETTs: insertion depth (cm) = height (cm)/11 + 5.5, weight (kg)/3 + 9.5 or 11 + 3/4 × age (years). The rates of appropriate tube placement of both pediatric cuffed ETTs were 87.5% (Hi-Contour) and 85.0% (Microcuff). Conclusions: Our formula and graphs may be easy to determine the optimal insertion depth of cuffed ETT even without depth marking in clinical practice. 展开更多
关键词 INSERTION depth INFANTS Small Children Cuffed ENDOTRACHEAL tubeS
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Q420B大规格角钢去除夹杂的研究与实践
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作者 刘志远 王重君 +1 位作者 栾文林 孔明姣 《宽厚板》 2025年第3期23-29,共7页
在以LD-LF-RH-CC工艺流程生产Q420B大规格角钢过程中,钢水中形成以Al_(2)O_(3)为主的复合夹杂物、以FeO-Al_(2)O_(3)为主的复合脱氧夹杂物和以FeO-Al_(2)O_(3)-C为主的不规则复合夹杂物。尽管经过RH精炼夹杂物数量明显减少,但仍然存在... 在以LD-LF-RH-CC工艺流程生产Q420B大规格角钢过程中,钢水中形成以Al_(2)O_(3)为主的复合夹杂物、以FeO-Al_(2)O_(3)为主的复合脱氧夹杂物和以FeO-Al_(2)O_(3)-C为主的不规则复合夹杂物。尽管经过RH精炼夹杂物数量明显减少,但仍然存在少量对钢材质量影响较大的大尺寸硅酸铝复合夹杂物。通过实验室模拟与生产相结合的方法,深入分析驱动气体流量、浸渍管插入深度对钢液循环气量和混匀时间的影响,并对其进行优化调整,将浸渍管插入深度调至550 mm,RH精炼循环气量优化为60 Nm^(3)/h或110 Nm^(3)/h,精炼时间稳定在20 min左右,确定最佳循环气量为60 Nm^(3)/h。优化调整后,对各类夹杂物进行统计分析,结果表明:夹杂物数量减少,夹杂物粒径≤15μm的比例为98%,满足了Q420B大规格角钢的标准要求。 展开更多
关键词 夹杂物 循环气量 浸渍管插入深度 提升气量
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基于磨料动能和浓度的后混合磨料水射流全局模拟研究
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作者 李震 李斌 +3 位作者 王广 乔志忠 孙恒阳 雷曌 《振动与冲击》 北大核心 2025年第7期76-85,95,共11页
通过光滑粒子流体动力学-离散元方法-有限元方法耦合算法建立了后混合磨料水射流混合加速到切削工件的全局模拟模型。该研究采用磨料动能和磨料浓度作为中介变量,分析了磨料水射流参数对切削深度、混砂管应力以及能量转换率的影响。试... 通过光滑粒子流体动力学-离散元方法-有限元方法耦合算法建立了后混合磨料水射流混合加速到切削工件的全局模拟模型。该研究采用磨料动能和磨料浓度作为中介变量,分析了磨料水射流参数对切削深度、混砂管应力以及能量转换率的影响。试验设计涵盖了不同横移速度和磨料流量条件下的切削深度数据,以验证模型的可靠性。结果表明:混合流动过程可以划分为四个阶段;在稳定阶段,水流速度呈现特定的变化趋势,而磨料表现出两种加速规律,水和磨料颗粒从混砂管喷出时速度基本一致。混砂管应力主要集中在过渡段和出口处;在相同粒径条件下,切削深度和出口应力与磨料动能呈非线性正相关;在相同磨料注射角和磨料密度条件下,过渡段应力受磨料浓度和动能的复合影响。此外,研究还确定了使工件切削深度最大化的最优磨料流量、粒径和密度,并对其相关性进行了分析;同时发现,磨料注射角度为90°,混砂管收敛角为20°能够有效减少过渡段应力,同时保证磨料动能不受影响。研究结果为磨料水射流参数优化提供了一定理论支持。 展开更多
关键词 能量转化率 磨料动能 磨料浓度 混砂管应力 切削深度
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深层页岩气井井筒气液流动规律及影响因素
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作者 巨生 刘捷 《科学技术与工程》 北大核心 2025年第21期8871-8878,共8页
随着深层页岩气开发过程中大规压裂导致产量快速递减,准确掌握气液流动规律是气井稳产的必要手段,通过建立两种井身轨迹结构的气井模型,应用OLGA软件对不同油管下深模型进行瞬态计算。结果表明:深层页岩气井A_(1)仅在造斜段及以上出现... 随着深层页岩气开发过程中大规压裂导致产量快速递减,准确掌握气液流动规律是气井稳产的必要手段,通过建立两种井身轨迹结构的气井模型,应用OLGA软件对不同油管下深模型进行瞬态计算。结果表明:深层页岩气井A_(1)仅在造斜段及以上出现段塞流,而B_(1)井在水平段及造斜段附近出现段塞流的情况。考虑到累计产气量与积液,深层页岩气井A_(1)、B_(1)油管下入水平段跟端时最佳,与深层两种井身轨迹结构对应的常规页岩气井油管最优下深分别为水平段跟端和1/3水平段处;深层页岩气井较常规页岩气井更有利于排采和生产。随着油管尺寸的减小,产气量越小,对应气体的临界携液流量也越小;页岩气组分中轻烃的含量越大,气体产量随之增大。该研究可为深层页岩气井排水采气工艺中油管下入合理位置提供参考。 展开更多
关键词 瞬态计算 最优下深 气井积液 深层页岩气 气液流动
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外加辅助阳极的高功率脉冲磁控溅射管内Cr涂层制备及其性能分析
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作者 王子嘉 李宇鑫 +3 位作者 胡天时 田修波 巩春志 张辉 《中国表面工程》 北大核心 2025年第1期99-106,共8页
工业生产中管筒件内表面的工作环境恶劣,对腐蚀和磨损等方面的性能有更高要求。为改善管筒件的内表面性能,采用管尾添加辅助阳极的高功率脉冲磁控溅射(Hi PIMS)技术对内径40 mm、长度120 mm碳钢管进行内壁Cr涂层制备。探究辅助阳极电压... 工业生产中管筒件内表面的工作环境恶劣,对腐蚀和磨损等方面的性能有更高要求。为改善管筒件的内表面性能,采用管尾添加辅助阳极的高功率脉冲磁控溅射(Hi PIMS)技术对内径40 mm、长度120 mm碳钢管进行内壁Cr涂层制备。探究辅助阳极电压对Cr靶放电特性和管内Cr沉积的可达深度、相结构及其力学性能的影响规律,分析外加辅助阳极后管内等离子体分布情况,并建立理论模型。结果表明,较高的辅助阳极电压下,基体电流有所增加,特别在管尾位置处。随着辅助阳极电压升高,管内Cr沉积可达深度整体提高,膜层致密度提升。Cr膜的涂层硬度和弹性模量均随着辅阳电压的提高先上升后下降。当辅助阳极电压40V时,Cr涂层可达深度最好,具有最高的硬度和弹性模量。在HiPIMS放电条件下,辅助阳极可以通过牵引电子实现对等离子体定向输运的调控,并显著提高管尾等离子体密度。实现了在管筒件内表面沉积Cr涂层,满足了管筒件内表面在恶劣环境下广泛应用的需求。 展开更多
关键词 高功率脉冲磁控溅射 管内壁镀膜 辅助阳极 等离子体分布 可达深度
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深层页岩气井油管下入时机及关键参数
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作者 石书强 吝少康 +4 位作者 田雨萌 叶长青 王珍 于庆印 陈丹琳 《石油钻采工艺》 北大核心 2025年第3期387-396,共10页
针对深层页岩气井因套管携液能力下降导致的积液问题,提出一种通过优化油管下入时机与关键参数来提升井筒携液效率、实现产量提升的解决方案。本研究基于井筒多相流理论和临界携液模型,采用现场数据修正的压力和临界携液模型进行计算,... 针对深层页岩气井因套管携液能力下降导致的积液问题,提出一种通过优化油管下入时机与关键参数来提升井筒携液效率、实现产量提升的解决方案。本研究基于井筒多相流理论和临界携液模型,采用现场数据修正的压力和临界携液模型进行计算,综合考虑日产气量、气液比、管径、井斜角及流体速度等关键参数,以井筒总压降最小化同时满足气体真实流速高于临界携液流速为标准,建立优选油管下入时机、油管尺寸及下入深度的三维判断图版。研究结果表明,油管下入时机与管径相关,对于Ø76 mm、Ø62 mm、Ø50.4 mm及Ø40 mm油管,套管生产转向油管生产的临界转换点的对应日产气量分别为4.2×10^(4)m^(3)、3.9×10^(4)m^(3)、3.5×10^(4)m^(3)及3.3×10^(4)m^(3);最优下入深度与生产阶段相关,当日产气量大于等于5×10^(4)m^(3)时,套管生产压降最小,无需下入油管,当日产气量小于该值时应将油管下至A靶点处进行生产可使井筒压降最小。该方法现场试验10口井,对日产气量的预测平均绝对误差为4.83%,X1井应用优化方案(日产气量3×10^(4)m^(3),下入Ø76 mm油管至5 000 m)后,日产气量提升了66.7%,该协同优化方法为深层页岩气井排水采气提供了有效指导。 展开更多
关键词 深层页岩气 压降模型 临界携液 油管尺寸 油管下深 下入时机
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局部自紧身管压坑允许深度曲线计算
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作者 杜中华 《机械工程师》 2025年第6期20-23,26,共5页
局部自紧身管仅对身管部分区域进行自紧,包括自紧段和单筒段,故压坑允许深度曲线计算更为复杂。由于我国自紧身管采用第三强度理论,单筒身管采用第二强度理论,对于局部自紧身管要统一采用第三强度理论,这就要反推基于第三强度理论的单... 局部自紧身管仅对身管部分区域进行自紧,包括自紧段和单筒段,故压坑允许深度曲线计算更为复杂。由于我国自紧身管采用第三强度理论,单筒身管采用第二强度理论,对于局部自紧身管要统一采用第三强度理论,这就要反推基于第三强度理论的单筒身管安全系数;针对自紧身管理论外形计算没有显式公式可用的问题可用试算法或者MATLAB中函数解决;射击条件变化会对压坑允许深度曲线产生显著影响。为了解决上述问题,提出了局部自紧身管压坑允许深度曲线的完整解决方案,依托某型火炮自紧身管的数值仿真实例证明了方案的可行性。 展开更多
关键词 自紧身管 压坑允许深度曲线 射击条件 数值仿真
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大变形凹坑管交错滚压成形数值模拟研究
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作者 谢帅 邹鑫 +4 位作者 李贞丽 彭佳辉 任爽 罗乙凯 曾国恩 《锻压技术》 北大核心 2025年第9期139-146,165,共9页
针对深凹坑管生产成本高、成形效率低的问题,提出一种交错式凹坑管滚压成形装置,并建立了凹坑管滚压成形数值模型,研究凹坑管的成形过程,分析了压头大小、挤压深度以及壁厚对光管成形力学性能的影响规律。结果表明:通过滚压成形装置中... 针对深凹坑管生产成本高、成形效率低的问题,提出一种交错式凹坑管滚压成形装置,并建立了凹坑管滚压成形数值模型,研究凹坑管的成形过程,分析了压头大小、挤压深度以及壁厚对光管成形力学性能的影响规律。结果表明:通过滚压成形装置中的两组滚轮,可在光管上成形交错排布的均匀凹坑。光管与压头接触后,管壁向内形成凹坑,凹坑中心处应力最大值为465.5 MPa,等效塑性应变为0.4;光管与压头未接触区域,管壁向外变形形成凸起。成形应力和等效塑性应变随椭圆球形压头长半轴长度a值的减小和短半轴长度b值的增大而减小,随挤压深度D和管壁厚度δ的增加而增加。 展开更多
关键词 深凹坑管 滚压成形 凹坑大小 凹坑深度 力学性能
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基于NSGA-Ⅱ算法的连续管下入深度优化研究
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作者 陈义洪 翁振康 +3 位作者 许得禄 娄增 徐传友 齐昌鑫 《阀门》 2025年第7期707-712,共6页
随着油气资源开发向深井、超深井及超长水平井等复杂结构井方向发展,连续管技术在冲砂、钻磨、测井等井下作业中成为关键技术工具,但在复杂井况下,连续管易受多因素耦合作用,导致下入深度不足,制约作业效率。本文基于刚杆模型构建了连... 随着油气资源开发向深井、超深井及超长水平井等复杂结构井方向发展,连续管技术在冲砂、钻磨、测井等井下作业中成为关键技术工具,但在复杂井况下,连续管易受多因素耦合作用,导致下入深度不足,制约作业效率。本文基于刚杆模型构建了连续管极限下入深度计算模型,综合考虑摩擦系数、流体密度、连续管尺寸及牵引力的耦合作用。通过与文献中的数据对比验证了模型的准确性,并将力学模型嵌入NSGA-Ⅱ算法迭代流程。将该优化方法在某5000 m水平井中应用,结果表明,优化后的连续管参数可使极限下入深度达到5000 m,成功解决了在2990 m处下入“锁死”问题。 展开更多
关键词 NSGA-Ⅱ算法 连续管 极限下入深度 优化
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机械油管打孔技术在苏里格气田的应用效果评价
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作者 王烁 《石油化工应用》 2025年第7期13-16,共4页
井下节流工艺在一定程度上可缓解苏里格气田气井携液能力差、单井产量递减快等问题,但随着生产周期的延长,在开发中后期适时打捞节流器已成为常用的工艺增产措施。预制式节流器由于位置较深,井筒情况复杂,打捞失败率居高不下,严重制约... 井下节流工艺在一定程度上可缓解苏里格气田气井携液能力差、单井产量递减快等问题,但随着生产周期的延长,在开发中后期适时打捞节流器已成为常用的工艺增产措施。预制式节流器由于位置较深,井筒情况复杂,打捞失败率居高不下,严重制约了气田的稳产增产。为此,引进了机械油管打孔技术,通过现场应用效果发现,通过在设计的打孔深度上实施机械油管打孔,并在井下建立生产通道,达到卸载井筒、辅助喷油的目的。同时适用于苏里格气田常规、定向及水平井等不同井型的增产上产。通过此关键技术的应用,5口试验井打孔初期平均日产气量达3.05×10^(4)m^(3),累计增产气量502.9×10^(4)m^(3),截至2024年年底,投入产出比为1.0∶13.2,累计产量得到大幅度提升,经济效益较好,增产效果显著。 展开更多
关键词 苏里格气田 疑难节流器 机械油管打孔 打孔深度 应用效果 经济效益 增产
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水平气井油管最优下深位置及局部压降研究
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作者 王大江 程阳 《能源与环保》 2025年第5期74-80,共7页
为了对水平气井油管下入位置提供理论依据,达到优化速度管柱及完井结构的目的,同时为了解决由于油管下入后产生的突缩部位而导致局部压力损失使井筒沿程压力分布计算不准确的问题,依托于室内物模实验,模拟了水平井油管下深不同位置,对... 为了对水平气井油管下入位置提供理论依据,达到优化速度管柱及完井结构的目的,同时为了解决由于油管下入后产生的突缩部位而导致局部压力损失使井筒沿程压力分布计算不准确的问题,依托于室内物模实验,模拟了水平井油管下深不同位置,对油管下深至水平段跟端、水平段1/3处、水平段2/3处、水平段趾端、斜井段上端等不同位置进行了模拟实验。从排液量及压力梯度多角度对比分析,得到了最优的油管下入深度为水平段1/3处,优化了完井结构,为现场排采施工及完井方案提供了指导。通过采用CFD软件模拟不同突缩比、不同产气量条件下的气液两相流动,分析了垂直向上突缩管气中液两相流在突缩管段处的流动情况,根据数值分析结果建立了适用于不同突缩比、不同流速下气液两相的局部损失计算方法。 展开更多
关键词 局部压降 雷诺数 油管下深位置 数值模拟
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National Survey of Attitudes and Practices of Endotracheal Tube Management in Infants and Small Children in Japan
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作者 Masayuki Shibasaki Yasuyuki Suzuki +3 位作者 Tetsuro Kagawa Yasuhiro Kogure Keiichiro Mizuno Nobuaki Shime 《Open Journal of Anesthesiology》 2019年第2期9-22,共14页
Background: Surveys of pediatric endotracheal tube (ETT) management previously reported that specialists in pediatric anesthesia and intensive care medicine preferred to use uncuffed ETTs for children younger than 8 t... Background: Surveys of pediatric endotracheal tube (ETT) management previously reported that specialists in pediatric anesthesia and intensive care medicine preferred to use uncuffed ETTs for children younger than 8 to 10 years of age. The aim of this study was to reveal the most recent attitudes and clinical practices of pediatric ETT management in Japan. Methods: The attitudes and clinical practices of pediatric ETT management were investigated using the data sheets of each institution and each patient. The data sheets contained information on patient characteristics and type of hospital, surgical procedures, devices used for intubation, and ETT information including types, size, depth, intracuff pressure (ICP), interval of ICP measurement, laryngeal packing, ETT exchange, airway complications, and reintubations. Results: The response rate of this survey was 66.7%. More than half of children older than 2 years of age were intubated with cuffed ETTs;83.5% of cuffed ETTs were used with the cuffs inflated, and ICP was measured in 80.7% of cuffed ETTs. More than half of ICP measurements were only taken at the time of intubation. Post-extubation stridor was rarely observed in cuffed (0.4%) or uncuffed ETTs (1.2%). The pediatric ETT management questionnaire revealed age-based size selection, differences in pressure of air leakage between cuffed (15 - 20 cmH2O) and uncuffed ETTs (20 - 30 cmH2O) of different sizes, the depthmarking method of insertion length. Continuous measurement of ICP was not common. Conclusion: This study revealed widespread use of cuffed ETTs in children older than 2 years of age, rarely occurrence of post-extubation stridor, inflation of cuffs, and practice of ICP measurement. 展开更多
关键词 Cuffed ENDOTRACHEAL tube Size Selection depth Determination Intracuff Pressure INFANTS SMALL CHILDREN
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含油海洋环境下316L仪表管点蚀深度预测模型研究 被引量:1
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作者 骆正山 刘月 +1 位作者 骆济豪 王小完 《材料保护》 CAS CSCD 2024年第8期32-37,46,共7页
为了提升316L不锈钢仪表管在含油海洋大气环境下点蚀深度的预测精度,建立了基于改进粒子群算法优化的直接离散灰色点蚀深度预测模型[SCPSO-DDGM(1,1,λ)]。首先以暴露实验点蚀数据为例,建立DDGM(1,1)模型,并利用新信息变权弱化缓冲算子... 为了提升316L不锈钢仪表管在含油海洋大气环境下点蚀深度的预测精度,建立了基于改进粒子群算法优化的直接离散灰色点蚀深度预测模型[SCPSO-DDGM(1,1,λ)]。首先以暴露实验点蚀数据为例,建立DDGM(1,1)模型,并利用新信息变权弱化缓冲算子、等维灰数递补对模型进行动态改进;后采用非线性变化惯性权重和正弦余弦学习因子提高粒子群算法(PSO)的寻优能力和收敛速度,引入高斯扰动策略增强PSO跳出局部最优的能力,进而用SCPSO对改进后的DDGM(1,1,λ)模型中的权重参数λ进行寻优;最终在MATLAB中进行仿真计算,分析对比SCPSO-DDGM(1,1,λ)模型与GM(1,1)、DDGM(1,1)、PSO-DDGM(1,1,λ)模型的预测结果。结果表明:在研究的时间区间内,经优化的新模型预测深度与实际深度高度吻合,较于对比模型性能更优。证明SCPSO-DDGM(1,1,λ)模型能够有效预测仪表管点蚀深度,为仪表管的腐蚀研究提供了新的思路与方法。 展开更多
关键词 含油海洋大气环境 316L不锈钢仪表管 点蚀深度 改进粒子群优化算法(SCPSO) DDGM(1 1 λ)模型
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基于轴向载荷离散模型的连续管下入性分析 被引量:2
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作者 曹银萍 谢凡 +3 位作者 冯佳佳 朱文宇 魏文澜 郑杰 《石油机械》 北大核心 2024年第12期1-7,共7页
连续管在水平井作业过程中易发生屈曲变形制约其作业深度,为此开展不同井段中连续管轴向载荷对其下入深度的影响研究。通过对井眼轨迹中的关键参数分析构建弯曲段全角平面,并基于软杆模型和构建的全角平面,综合考虑连续管刚性、流体摩... 连续管在水平井作业过程中易发生屈曲变形制约其作业深度,为此开展不同井段中连续管轴向载荷对其下入深度的影响研究。通过对井眼轨迹中的关键参数分析构建弯曲段全角平面,并基于软杆模型和构建的全角平面,综合考虑连续管刚性、流体摩阻、井壁接触摩阻和屈曲后的附加接触摩阻,建立了连续管轴向载荷计算模型;通过迭代法并结合屈曲状态分析对某井进行算例分析。分析结果表明:连续管在垂直段与斜直段更容易发生螺旋屈曲;随着摩擦因数由0.10增加到0.35,螺旋屈曲长度增加到1189.19 m,下入深度由4370.00 m减小到3905.41 m;摩擦因数为0.25时,工作钻压增加到2.5 kN,下入深度由4370.00 m减小到4148.48 m。可见,在轴向压力作用下,连续管螺旋屈曲长度与摩擦因数成正比,下入深度与摩擦因数和工作钻压均成反比。所得结论可为连续管下入性研究及施工参数选择提供技术参考。 展开更多
关键词 水平井 连续管下入性 轴向载荷 螺旋屈曲 下入深度 摩擦因数
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Comparison of the Effectiveness of Marked Suction Tubes vs. Plain Suction Tubes in Pediatric Mechanically Ventilated Patients
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作者 Kexin Yang Yang Zhang +5 位作者 Menghui Duan Qiuju Liang Jianfei Zhang Ping Kong Mengqi Duan Xiangwei Chen 《Open Journal of Pediatrics》 2023年第6期774-784,共11页
Introduction: Endotracheal suction plays a crucial role in the management of mechanically ventilated patients. This study aims to evaluate the clinical effectiveness and safety of suction tubes with markings in mechan... Introduction: Endotracheal suction plays a crucial role in the management of mechanically ventilated patients. This study aims to evaluate the clinical effectiveness and safety of suction tubes with markings in mechanically ventilated pediatric patients. Materials and Methods: A randomized assignment was carried out on a cohort of 52 pediatric patients who underwent mechanical ventilation in the Pediatric Intensive Care Unit at the Third Affiliated Hospital of Sun Yat-sen University, covering the period from January 2022 to December 2022. These patients were divided into two groups: an improved group (n = 26) utilizing marked suction tubes, and a regular group (n = 26) employing conventional suction tubes. The objective of our study was to evaluate the clinical effectiveness of marked suction tubes. Results: The effects of the improved group on the vital signs of children undergoing mechanical ventilation were small and statistically significant compared with the regular group (p < 0.05). Additionally, the improved group exhibited a reduced frequency of sputum suction, shorter mechanical ventilation duration, and fewer days of hospitalization in the PICU compared to the regular group during the ventilation period. Notably, the difference in the duration of PICU hospitalization was statistically significant (p < 0.05). Moreover, the incidence of adverse reactions in the improved group was notably lower, with statistically significant differences observed in airway mucous membrane damage and irritating cough when compared to the regular group (p < 0.05). Conclusion: The utilization of marked suction tubes provides clinical nurses with clear guidance for performing suctioning with ease, efficiency and safety. Consequently, advocating for the widespread implementation of marked suction tubes in clinical practice is a commendable pursuit. 展开更多
关键词 Marked Suction tubes Endotracheal Suction Mechanical Ventilation Different depth of Aspiration
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盐湖大气环境下316 L仪表管点蚀深度预测研究
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作者 骆正山 刘月 《中国安全生产科学技术》 CAS CSCD 北大核心 2024年第6期105-110,共6页
为提高316 L仪表管在盐湖大气环境下点蚀深度的预测精度,采用变阶平均弱化缓冲算子、积分背景值和新陈代谢对分数阶累加灰色模型FGM(1,1,r)进行改进,首先通过改进Tent混沌映射、莱维飞行和区间自适应反向学习策略提高黏菌算法(SMA)的寻... 为提高316 L仪表管在盐湖大气环境下点蚀深度的预测精度,采用变阶平均弱化缓冲算子、积分背景值和新陈代谢对分数阶累加灰色模型FGM(1,1,r)进行改进,首先通过改进Tent混沌映射、莱维飞行和区间自适应反向学习策略提高黏菌算法(SMA)的寻优能力和收敛速度,随后利用改进黏菌算法(ISMA)对FGM(1,1,r,ρ)中的参数r和ρ进行寻优,最后构建仪表管ISMA-FGM(1,1,r,ρ)点蚀深度预测模型。研究结果表明:经优化的新模型比原模型误差更小、拟合度更高,在仪表管点蚀深度预测方面具有更好的性能。研究结果可为仪表管道系统的完整性评价和风险预警提供参考。 展开更多
关键词 盐湖大气环境 316 L仪表管 点蚀深度 改进黏菌算法(ISMA) FGM(1 1 r)模型
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