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
针对锚线斜拉作用下吸力筒与砂土相互作用的微观特征仍不清楚这一问题,采用离散元(discrete element method,简称DEM)-有限元(finite element method,简称FEM)耦合数值方法,从宏观到微观角度分析系泊点深度对吸力筒基础抗拔性能的影响...针对锚线斜拉作用下吸力筒与砂土相互作用的微观特征仍不清楚这一问题,采用离散元(discrete element method,简称DEM)-有限元(finite element method,简称FEM)耦合数值方法,从宏观到微观角度分析系泊点深度对吸力筒基础抗拔性能的影响。在建模中,采用FEM中有限元网格来模拟吸力筒,采用DEM中颗粒来模拟吸力筒周围砂土,并通过控制滚轴运动来模拟锚线的拉作用。结果表明:吸力筒的拉力-位移曲线存在峰值拉力,且与不同系泊点深度下吸力筒运动模式有密切关系;吸力筒旋转方向、拔出位移的反转临界系泊深度点位于吸力筒从顶部往下h=66.7%深度附近(即吸力筒深度的2/3处,h为系泊深度)。此外,从颗粒尺度分析了土体变形及破坏行为,最终确定了吸力筒-颗粒土相互作用的破坏模式。研究结果表明,忽略锚线的系泊点深度将会导致误判吸力筒的承载能力及与土体的破坏模式。展开更多
The visual fidelity of bleeding simulation in a surgical simulator is critical since it will affect not only the degree of visual realism,but also the user’s medical judgment and treatment in real-life settings.The c...The visual fidelity of bleeding simulation in a surgical simulator is critical since it will affect not only the degree of visual realism,but also the user’s medical judgment and treatment in real-life settings.The conventional marching cubes surface rendering algorithm provides excellent visual effect in rendering gushing blood,however,it is insufficient for blood flow,which is very common in surgical procedures,since in this case the rendered surface and depth textures of blood are rough.In this paper,we propose a new method called the mixed depth rendering for rendering blood flow in surgical simulation.A smooth height field is created to minimize the height difference between neighboring particles on the bleeding surface.The color and transparency of each bleeding area are determined by the number of bleeding particles,which is consistent with the real visual effect.In addition,there is no much extra computational cost.The rendering of blood flow in a variety of surgical scenarios shows that visual feedback is much improved.The proposed mixed depth rendering method is also used in a neurosurgery simulator that we developed.展开更多
The subsea anchor piles of offshore wind power floating platform structures are mainly subjected to uplift and horizontal loads, and this paper focuses on the case of horizontal loads. A three-dimensional numerical si...The subsea anchor piles of offshore wind power floating platform structures are mainly subjected to uplift and horizontal loads, and this paper focuses on the case of horizontal loads. A three-dimensional numerical simulation study of the horizontal pullout characteristics of wind power suction anchor piles in clay layers was carried out to reveal the horizontal movement state of the anchor piles during horizontal pile pullout, the range of pile depth at the pullout point where the horizontal movement is achieved (referred to as the horizontal movement range), the relationship between the pullout load and the ultimate load during the horizontal movement, and the optimal location of the pullout point for the horizontal movement. The results show that at certain pull-out points, the anchor pile produces an overall horizontal movement state under suitable horizontal pull-out loads. The depth of the pile pull-out point for horizontal movement is in the middle and lower part of the pile, i.e. 14.2 m to 14.5 m. The horizontal pull-out load of 24,000 kN at a depth of 14.5 m within the pile horizontal movement range of 14.2m to 14.5 m is the maximum ultimate horizontal pull-out load;the optimum pull-out point depth is 14.5 m at 0.275 L (L is the pile length). For each pull-out point of the anchor pile in horizontal movement, the horizontal pull-out load in horizontal movement and the horizontal ultimate pull-out load existed and it was found that the two values were not exactly the same, the values were compared and it was found that at the optimum pull-out point the value of the ultimate horizontal pull-out load/horizontal pull-out load in horizontal movement tended to 1.展开更多
文摘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.
文摘针对锚线斜拉作用下吸力筒与砂土相互作用的微观特征仍不清楚这一问题,采用离散元(discrete element method,简称DEM)-有限元(finite element method,简称FEM)耦合数值方法,从宏观到微观角度分析系泊点深度对吸力筒基础抗拔性能的影响。在建模中,采用FEM中有限元网格来模拟吸力筒,采用DEM中颗粒来模拟吸力筒周围砂土,并通过控制滚轴运动来模拟锚线的拉作用。结果表明:吸力筒的拉力-位移曲线存在峰值拉力,且与不同系泊点深度下吸力筒运动模式有密切关系;吸力筒旋转方向、拔出位移的反转临界系泊深度点位于吸力筒从顶部往下h=66.7%深度附近(即吸力筒深度的2/3处,h为系泊深度)。此外,从颗粒尺度分析了土体变形及破坏行为,最终确定了吸力筒-颗粒土相互作用的破坏模式。研究结果表明,忽略锚线的系泊点深度将会导致误判吸力筒的承载能力及与土体的破坏模式。
基金supported the National Science Foundation of China(61773051,61761166011,51705016)Beijing Natural Science Foundation(4172048)the Fundamental Research Funds for the Central Universities(2017JBZ003)
文摘The visual fidelity of bleeding simulation in a surgical simulator is critical since it will affect not only the degree of visual realism,but also the user’s medical judgment and treatment in real-life settings.The conventional marching cubes surface rendering algorithm provides excellent visual effect in rendering gushing blood,however,it is insufficient for blood flow,which is very common in surgical procedures,since in this case the rendered surface and depth textures of blood are rough.In this paper,we propose a new method called the mixed depth rendering for rendering blood flow in surgical simulation.A smooth height field is created to minimize the height difference between neighboring particles on the bleeding surface.The color and transparency of each bleeding area are determined by the number of bleeding particles,which is consistent with the real visual effect.In addition,there is no much extra computational cost.The rendering of blood flow in a variety of surgical scenarios shows that visual feedback is much improved.The proposed mixed depth rendering method is also used in a neurosurgery simulator that we developed.
文摘The subsea anchor piles of offshore wind power floating platform structures are mainly subjected to uplift and horizontal loads, and this paper focuses on the case of horizontal loads. A three-dimensional numerical simulation study of the horizontal pullout characteristics of wind power suction anchor piles in clay layers was carried out to reveal the horizontal movement state of the anchor piles during horizontal pile pullout, the range of pile depth at the pullout point where the horizontal movement is achieved (referred to as the horizontal movement range), the relationship between the pullout load and the ultimate load during the horizontal movement, and the optimal location of the pullout point for the horizontal movement. The results show that at certain pull-out points, the anchor pile produces an overall horizontal movement state under suitable horizontal pull-out loads. The depth of the pile pull-out point for horizontal movement is in the middle and lower part of the pile, i.e. 14.2 m to 14.5 m. The horizontal pull-out load of 24,000 kN at a depth of 14.5 m within the pile horizontal movement range of 14.2m to 14.5 m is the maximum ultimate horizontal pull-out load;the optimum pull-out point depth is 14.5 m at 0.275 L (L is the pile length). For each pull-out point of the anchor pile in horizontal movement, the horizontal pull-out load in horizontal movement and the horizontal ultimate pull-out load existed and it was found that the two values were not exactly the same, the values were compared and it was found that at the optimum pull-out point the value of the ultimate horizontal pull-out load/horizontal pull-out load in horizontal movement tended to 1.
