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Suppression of Cell Traction Force and Enhanced Force Polarity are Key Factors in Vascular Smooth Muscle Cell Differentiation Induced by Low Serum Culture
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作者 Kazuaki Nagayama Harunobu Tatsuno 《Journal of Biosciences and Medicines》 2025年第2期243-255,共13页
Vascular smooth muscle cells (VSMCs) in the arterial walls play important roles in regulating vascular contraction and dilation. VSMCs actively remodel the arterial walls and dedifferentiate from the contractile to th... Vascular smooth muscle cells (VSMCs) in the arterial walls play important roles in regulating vascular contraction and dilation. VSMCs actively remodel the arterial walls and dedifferentiate from the contractile to the synthetic phenotype under pathological conditions. The mechanism underlying phenotypic transition of VSMCs is important for understanding its role in the pathophysiology of disease. Although numerous studies have reported various biochemical pathways that stimulate the phenotypic transition of VSMCs, very little is known about relation between their phenotypic transition and cellular traction force, which affects many cellular functions. In this study, we induced the differentiation of cultured VSMCs from the synthetic to the contractile phenotype by a low-serum cultivation and investigated changes in the cell traction forces using traction force microscopy technique. The expression of α-SMA, a contractile phenotype marker protein, was significantly upregulated with maturation of actin stress fibers in the low-serum culture, indicating VSMC differentiation was promoted in our experiments. The cells changed their morphology to an elongated bipolar shape, and the direction of the cell traction forces tended to align in the direction of the cell’s major axis. Despite the promotion of contractile differentiation in VSMCs, the overall cell traction forces were significantly reduced, indicating that excessive cell mechanical tension, which might induce cell proliferation and migration, was suppressed during contractile differentiation. These results suggest that suppression of cell traction force and enhanced force polarity might be key factors in VSMC differentiation induced by low serum culture. 展开更多
关键词 Cell Biomechanics MECHANOBIOLOGY PHENOTYPE CYTOSKELETON traction Force Microscopy
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Curative Efficacy of Cyclic Flexion Traction on Lumbar Disc Herniation
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作者 Yuanyang ZHANG 《Medicinal Plant》 2025年第3期69-71,83,共4页
[Objectives]To investigate the clinical efficacy of Cyclic Flexion Traction(CFT)in treating Lumbar Disc Herniation(LDH)and its effects on lumbocrural pain relief,functional improvement,and nerve root decompression.[Me... [Objectives]To investigate the clinical efficacy of Cyclic Flexion Traction(CFT)in treating Lumbar Disc Herniation(LDH)and its effects on lumbocrural pain relief,functional improvement,and nerve root decompression.[Methods]Seventy LDH patients treated at the orthopedic rehabilitation outpatient and inpatient departments of Shiyan Taihe Hospital from June 2022 to December 2024 were randomly divided into a treatment group(CFT therapy,n=35)and a control group(traditional traction,n=35).The treatment group received cyclic flexion traction(traction force of 30%-50%body weight with a cycle of 60-30-30 sec),while the control group received supine position linear traction.Both groups underwent 4 weeks of treatment,with assessments including visual analog scale(VAS),Oswestry Disability Index(ODI),and straight leg raising test(SLRT)angles.[Results]The treatment group showed a significantly greater reduction in VAS scores(from 6.97 to 2.31)compared to the control group(from 6.89 to 3.74)(P<0.05).Similarly,ODI improvement(41.62→15.73 compared with 40.98→22.84)and SLRT angle increase(41.23°→76.47°compared with 42.09°→64.19°)were more pronounced in the treatment group(all P<0.05).[Conclusions]Through dynamic decompression mechanisms,CFT therapy demonstrates superior efficacy to traditional traction in pain relief,functional recovery,and nerve root decompression(effective rate 94.29%compared with 77.14%,P<0.05),representing a superior non-surgical treatment option. 展开更多
关键词 Lumbar Disc HERNIATION (LDH) traction therapy CYCLIC FLEXION traction Dysfunction VAS score Straight leg RAISING test (SLRT)
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特瑞堡农业轮胎TM800 Progressive Traction®开启全新篇章
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《农业机械》 2025年第5期23-23,共1页
农业领域的持续变革对设备制造商提出了更高要求。随着耕作技术日趋精密化,农机及其配套组件必须同步升级以应对挑战。作为最传统同时又最重要的零部件之一,轮胎更应以持续创新满足现代化农业需求。正是这种对技术精进的追求,推动了TM80... 农业领域的持续变革对设备制造商提出了更高要求。随着耕作技术日趋精密化,农机及其配套组件必须同步升级以应对挑战。作为最传统同时又最重要的零部件之一,轮胎更应以持续创新满足现代化农业需求。正是这种对技术精进的追求,推动了TM800 PT双动力花纹系列产品的诞生——在经典的TM800轮胎基础上,结合特瑞堡专利技术,开启高效农耕新纪元。 展开更多
关键词 TM800 Progressive traction 农业轮胎
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Zero‑emission traction for rail
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作者 Colin Cole Maksym Spiryagin +2 位作者 Qing Wu Esteban Bernal Arango Chris Bosomworth 《Railway Engineering Science》 2025年第3期359-378,共20页
Replacing the energy density and convenience of diesel fuel for all forms of fossil fuel-powered trains presents significant challenges.Unlike the traditional evolutions of rail which has largely self-optimised to dif... Replacing the energy density and convenience of diesel fuel for all forms of fossil fuel-powered trains presents significant challenges.Unlike the traditional evolutions of rail which has largely self-optimised to different fuels and cost structures over 150 years,the challenges now present with a timeline of just a few decades.Fortunately,unlike the mid-1800s,simulation and modelling tools are now quite advanced and a full range of scenarios of operations and train trips can be simulated before new traction systems are designed.Full trip simulations of large heavy haul trains or high speed passenger trains are routinely completed controlled by emulations of human drivers or automated control systems providing controls of the“virtual train”.Recent developments in digital twins can be used to develop flexible and dynamic models of passenger and freight rail systems to support the new complexities of decarbonisation efforts.Interactions between many different traction components and the train multibody system can be considered as a system of systems.Adopting this multi-modelling paradigm enables the secure and integrated interfacing of diverse models.This paper demonstrates the application of the multi-modelling approach to develop digital twins for rail decarbonisation traction and it presents physics-based multi-models that include key components required for studying rail decarbonisation problems.Specifically,the challenge of evaluating zero-emission options is addressed by adding further layers of modelling to the existing fully detailed multibody dynamics simulations.The additional layers detail control options,energy storage,the alternate traction system components and energy management systems.These traction system components may include both electrical system and inertia dynamics models to accurately represent the driveline and control systems.This paper presents case study examples of full trip scenarios of both long haul freight trains and higher speed passenger trains.These results demonstrate the many complex scenarios that are difficult to anticipate.Flowing on from this,risks can be assessed and practical designs of zero-emission systems can be proposed along with the required recharging or refuelling systems. 展开更多
关键词 LOCOMOTIVE Virtual train Simulation Digital twin traction BRAKING Energy Storage
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Combined application of the preclosure technique and traction approach facilitates endoscopic full-thickness resection of gastric submucosal tumors
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作者 Qing-Qing Zu Yan You +4 位作者 Ai-Zhi Chen Xiu-Rong Wang Si-Han Zhang Feng-Lin Chen Miao Liu 《World Journal of Gastrointestinal Surgery》 2025年第3期79-86,共8页
BACKGROUND Gastrointestinal submucosal tumors(SMTs)mostly grew in the lumen,but also some of the lesions were extraluminal,in which the stomach was the most co-mmon site.Gastrointestinal stromal tumor account for a la... BACKGROUND Gastrointestinal submucosal tumors(SMTs)mostly grew in the lumen,but also some of the lesions were extraluminal,in which the stomach was the most co-mmon site.Gastrointestinal stromal tumor account for a large proportion of SMT.Due to the deep lesion location of gastric SMT,endoscopic submucosal dissection related techniques are difficult to operate,while endoscopic full-thickness rese-ction(EFTR)has been widely used in clinical practice because it is less invasive and can preserve the physiological structure and function of the stomach.Ho-wever,complete closure of the gastrectomy site after EFTR is critical.If the closure is incomplete,it may cause peritonitis,late perforation and other conditions,and even require further surgical intervention.Although there are currently a number of suture devices and techniques that can be used to promote closure,they have the problem of requiring additional equipment or being inconvenient to use.Although metal clips are widely used,their effectiveness depends on the size and tension of the defect.Therefore,an effective and convenient endoscopic closure technique is urgently needed to solve the closure problem of gastric SMTs after treatment.AIM To investigate the effect of combined application of the preclosure technique and dental floss traction in gastric wound closure following EFTR.METHODS In this study,the data of 94 patients treated for gastric SMTs at the Gastrointestinal Endoscopy Center of the Affiliated Union Hospital of Fujian Medical University from April 2022 to May 2023 were retrospectively analyzed.The patients were divided into a preclosure group(54 patients)and a non-preclosure group(40 patients)on the basis of the timing of wound closure with titanium clips after dental floss traction-assisted EFTR.Each patient in the preclosure group had their wounds preclosed with titanium clips after subtotal lesion resection,whereas each patient in the non-preclosure group had their wounds closed with titanium clips after total lesion resection.The lesion size,wound closure time,number of titanium clips used,incidence of postoperative complications,and postoperative hospitalization time were compared between the two groups.RESULTS The wound closure time was significantly shorter in the preclosure group than in the non-preclosure group(6.69±2.109 minutes vs 11.65±3.786 minutes,P<0.001).The number of titanium clips used was significantly lower in the preclosure group(8.93±2.231)than in the non-preclosure group(12.05±4.495)(P<0.001).There was no sig-nificant difference between the two groups in terms of the need for an indwelling gastric tube or the length of postoperative hospital stay(6.41±1.31 vs 6.13±1.06 days).For all patients in the preclosure group and the non-preclosure group,resection was completed successfully without bleeding,abdominal pain,abdominal distension,or other postoperative complications.CONCLUSION Application of the preclosure technique combined with dental floss traction can be used intraoperatively to effectively close the surgical wound in patients undergoing EFTR,reliably preventing the tumor from falling into the peritoneal cavity. 展开更多
关键词 Gastric submucosal tumor Dental floss traction Endoscopic full-thickness resection Preclosure technique
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Influence of nonlinear contact stiffness on frequency veering of aircraft towbarless traction system
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作者 Xiaoyun LI Bo HU +2 位作者 Yijun CHAI Xiongwei YANG Yueming LI 《Chinese Journal of Aeronautics》 2025年第9期251-266,共16页
The variation of the nonlinear contact stiffness induced by the elastic wheel-holding effect between the aircraft and tractor has an important effect on the vibration characteristics of an airfield towbarless traction... The variation of the nonlinear contact stiffness induced by the elastic wheel-holding effect between the aircraft and tractor has an important effect on the vibration characteristics of an airfield towbarless traction system,making it essential for ensuring the safety of this emerging towing-out mode.In this paper,the frequency evolutionary tendency of the traction system is studied and obtained considering the variation of nonlinear contact stiffness for the first time.A novel modal analysis method,based on a derived nonlinear contact relationship,is proposed to investigate the vibration characteristics for mechanical system.Frequency veering and mode exchange phenomena in the low-order modes are observed due to the variation of nonlinear contact stiffness.These findings are further validated by the experimental results of a scaled-down model.In addition,it is also found that the veering critical point will be shifted with the external loads.The study provides valuable insights into the vibration characteristics and frequency veering behavior of similar mechanism-based systems,such as towbarless traction system,and has important implications for improving their design and operational performance. 展开更多
关键词 Frequency veering Landing gear(aircraft) Nonlinear contact stiffness Towbarless traction system Vibration analysis
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A Boundary-Type Meshless Method for Traction Identification in Two-Dimensional Anisotropic Elasticity and Investigating the Effective Parameters
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作者 Mohammad-Rahim Hematiyan 《Computers, Materials & Continua》 2025年第2期3069-3090,共22页
The identification of the traction acting on a portion of the surface of an anisotropic solid is very important in structural health monitoring and optimal design of structures. The traction can be determined using in... The identification of the traction acting on a portion of the surface of an anisotropic solid is very important in structural health monitoring and optimal design of structures. The traction can be determined using inverse methods in which displacement or strain measurements are taken at several points on the body. This paper presents an inverse method based on the method of fundamental solutions for the traction identification problem in two-dimensional anisotropic elasticity. The method of fundamental solutions is an efficient boundary-type meshless method widely used for analyzing various problems. Since the problem is linear, the sensitivity analysis is simply performed by solving the corresponding direct problem several times with different loads. The effects of important parameters such as the number of measurement data, the position of the measurement points, the amount of measurement error, and the type of measurement, i.e., displacement or strain, on the results are also investigated. The results obtained show that the presented inverse method is suitable for the problem of traction identification. It can be concluded from the results that the use of strain measurements in the inverse analysis leads to more accurate results than the use of displacement measurements. It is also found that measurement points closer to the boundary with unknown traction provide more reliable solutions. Additionally, it is found that increasing the number of measurement points increases the accuracy of the inverse solution. However, in cases with a large number of measurement points, further increasing the number of measurement data has little effect on the results. 展开更多
关键词 traction identification inverse method anisotropic elasticity load identification method of fundamental solutions measurement location
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Halo gravity traction for pediatric scoliosis and kyphoscoliosis:A review of current evidence and best practices
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作者 Meet A Jain Arjun Dhawale +4 位作者 Md Zafar Iqbal Atif Naseem Bhushan Sagade Apurba Gorain Abhay Nene 《World Journal of Orthopedics》 2025年第12期56-70,共15页
The surgical treatment of severe scoliosis and kyphoscoliosis in the pediatric population is complicated and has high morbidity and mortality risks.Severe scoliosis has traditionally been defined by a coronal Cobb ang... The surgical treatment of severe scoliosis and kyphoscoliosis in the pediatric population is complicated and has high morbidity and mortality risks.Severe scoliosis has traditionally been defined by a coronal Cobb angle of greater than 90°or 100°.The usual corrective methods for these patients have been anterior or posterior release and osteotomies using a combined anterior-posterior or posterior-only approach.Many of these patients have pre-existing pulmonary compromise;therefore,an anterior approach is often not reasonable or possible.Acute correction of a deformity may also cause neurologic injury.Halo gravity traction(HGT)allows for progressive,gradual,and sustained correction of the spinal deformity in the coronal,sagittal,and axial planes,leading to a decrease in the amount of correction needed at definitive posterior fusion.This relates to decreased postoperative neurologic deficit and improved pulmonary function.Preoperative HGT has evolved to be the surgical adjunct in the treatment of severe spinal deformity.Indications for HGT,best protocols of application,and optimal duration of traction still lack uniformity;thus,a review of the literature remains relevant and necessary.This review summarizes the existing literature on HGT,including its indications,applications,duration of traction,and associated complications. 展开更多
关键词 Halo gravity traction Severe pediatric scoliosis Severe pediatric kyphoscoliosis Cobb angle SCOLIOSIS KYPHOSCOLIOSIS
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Analysis of Therapeutic Effects of Dental Arch Splint Intermaxillary Traction Combined with Rigid Internal Fixation in Patients with Facial Comminuted Fractures
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作者 Xiaohua Zhang 《Journal of Clinical and Nursing Research》 2025年第1期81-87,共7页
Objective: To analyze the therapeutic effect of combining dental arch splint intermaxillary traction with rigid internal fixation for the treatment of facial comminuted fractures. Methods: Sixty patients with facial c... Objective: To analyze the therapeutic effect of combining dental arch splint intermaxillary traction with rigid internal fixation for the treatment of facial comminuted fractures. Methods: Sixty patients with facial comminuted fractures admitted for treatment between July 2023 and December 2024 were selected. Using a random number table method, 30 patients were assigned to the observation group, where moderate traction using a dental arch splint combined with rigid internal fixation was applied. Another 30 patients were assigned to the control group and only received dental arch splint traction treatment. The total effective rate, postoperative recovery indicators, periodontal status, complication rate, and quality of life scores were compared between the two groups. Results: The total effective rate in the observation group was higher than that in the control group. The postoperative recovery indicators and periodontal status in the observation group were superior to those in the control group. The complication rate and quality of life score were lower in the observation group compared to the control group, with P < 0.05. Conclusion: Combining dental arch splint intermaxillary traction with rigid internal fixation can improve the periodontal status and quality of life of patients with facial comminuted fractures, shorten postoperative recovery time, reduce various complications, and enhance surgical efficacy. 展开更多
关键词 Dental arch splint intermaxillary traction Rigid internal fixation Facial comminuted fracture Therapeutic effect
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Data-driven measurement performance evaluation of voltage transformers in electric railway traction power supply systems
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作者 Zhaoyang Li Muqi Sun +5 位作者 Jun Zhu Haoyu Luo Qi Wang Haitao Hu Zhengyou He Ke Wang 《Railway Engineering Science》 2025年第2期311-323,共13页
Critical for metering and protection in electric railway traction power supply systems(TPSSs),the measurement performance of voltage transformers(VTs)must be timely and reliably monitored.This paper outlines a three-s... Critical for metering and protection in electric railway traction power supply systems(TPSSs),the measurement performance of voltage transformers(VTs)must be timely and reliably monitored.This paper outlines a three-step,RMS data only method for evaluating VTs in TPSSs.First,a kernel principal component analysis approach is used to diagnose the VT exhibiting significant measurement deviations over time,mitigating the influence of stochastic fluctuations in traction loads.Second,a back propagation neural network is employed to continuously estimate the measurement deviations of the targeted VT.Third,a trend analysis method is developed to assess the evolution of the measurement performance of VTs.Case studies conducted on field data from an operational TPSS demonstrate the effectiveness of the proposed method in detecting VTs with measurement deviations exceeding 1%relative to their original accuracy levels.Additionally,the method accurately tracks deviation trends,enabling the identification of potential early-stage faults in VTs and helping prevent significant economic losses in TPSS operations. 展开更多
关键词 Voltage transformer traction power supply system Measurement performance Data-driven evaluation Abrupt change detection Bootstrap confidence interval
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A novel balance method for determining the energy efficiency of electric traction networks
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作者 Konstantin Suslov Andrey Kryukov +2 位作者 Aleksandr Cherepanov Andrey Batukhtin Yanhong Luo 《Global Energy Interconnection》 2025年第4期640-656,共17页
Modern electric traction networks(ETN)are equipped with automated systems for commercial accounting of power consumption(ASCAPC),which allows solving properly the problems of enhancing the energy efficiency of transpo... Modern electric traction networks(ETN)are equipped with automated systems for commercial accounting of power consumption(ASCAPC),which allows solving properly the problems of enhancing the energy efficiency of transportation processes.Energy efficiency of ETNs is defined as the amount of power losses in ETN components:overhead catenary systems and traction transformers.Due to the instability of traction loads and changes in their location in space,the electric traction network is different from the general network.It is necessary to develop an approach for loss analysis in traction networks and in transformers of traction substations.To solve this prob-lem,a balance-based technique for power loss calculation in traction networks based on ASCAPC data is proposed.First,the balance-based technique presented here breaks down the power consumption of the train by source.Then,calculates technical power losses in 25 and 225 kV traction networks as well as in traction transformers.Last,the technique is implemented in the form of an algorithm tested on real-life data and it is ready for practical use. 展开更多
关键词 Electric traction networks Automated systems for commercial accounting of power consumption Electricity losses Source breakdown of electricity consumption
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基于混合线路的高压专线贯通供电系统性能分析与优化
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作者 张丽艳 王凡 +1 位作者 李澳 贺昆 《西南交通大学学报》 北大核心 2026年第1期178-188,共11页
针对高压专线贯通供电系统中电缆应用引发的工频过电压与高成本问题,提出基于混合线路的优化配置方案.首先,利用二端口网络理论构建系统空载等效电路模型,结合混合线路分布参数特性,理论推导沿线电压与空载环流分布规律;其次,通过端口... 针对高压专线贯通供电系统中电缆应用引发的工频过电压与高成本问题,提出基于混合线路的优化配置方案.首先,利用二端口网络理论构建系统空载等效电路模型,结合混合线路分布参数特性,理论推导沿线电压与空载环流分布规律;其次,通过端口等效建立系统π型等值电路,并采用网络分裂算法构建多负荷统一潮流模型,提出系统等值阻抗与牵引网极限供电距离计算方法,定量评估混合线路的供电能力;进一步,以全寿命周期成本最优为目标,优化电缆与架空线安装比例.仿真结果表明,“电缆+架空线”方案可有效抑制工频过电压,降低空载电流至纯电缆方案的1/3,同时保留电缆长距离供电优势(极限供电距离达95 km),较传统方案节省投资约510万元. 展开更多
关键词 同相牵引供电 混合线路 电容效应 潮流计算 优化
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三维牵引钩导板辅助对下颌阻生异位尖牙的矫治效果观察
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作者 卢春燕 徐泽 任海峰 《中国美容医学》 2026年第2期138-141,共4页
目的:探讨三维牵引钩导板辅助对下颌阻生异位尖牙的矫治效果。方法:选择2018年4月-2023年4月在笔者医院接受治疗的96例下颌阻生异位尖牙患者为研究对象,共96颗阻生牙。采用随机数字表法将患者分为观察组和对照组,每组48例,对照组采用常... 目的:探讨三维牵引钩导板辅助对下颌阻生异位尖牙的矫治效果。方法:选择2018年4月-2023年4月在笔者医院接受治疗的96例下颌阻生异位尖牙患者为研究对象,共96颗阻生牙。采用随机数字表法将患者分为观察组和对照组,每组48例,对照组采用常规矫治方案,观察组基于数字化模型结合CBCT 3D模型矫治。记录两组患者的矫正成功率及矫治前至尖牙牙冠移动至侧切牙牙根远中位时(矫治后)的牵引时长,比较两组患者矫治前后邻牙的吸收状态,包括矫治前后冠状面下颌侧切牙、中切牙的牙根面积及长度,轴向切面下颌中切牙、侧切牙的牙根中和牙根尖1/3处的截面面积。结果:两组患者经5~12个月的矫治,下颌阻生异位尖牙均排齐至牙列。观察组牵引时长(6.43±0.71)个月,短于对照组的(8.31±0.58)个月(P<0.05)。矫治后,观察组下颌侧切牙和中切牙的牙根面积及长度与矫治前比较,差异无统计学意义(P>0.05);对照组下颌侧切牙和中切牙的牙根面积及长度低于矫正前(P<0.05)。矫治后,观察组下颌侧切牙和中切牙的牙根中1/3截面面积及牙根尖1/3截面面积与矫正前比较,差异无统计学意义(P>0.05);对照组下颌侧切牙和中切牙的牙根中1/3截面面积及牙根尖1/3截面面积低于矫治前(P<0.05)。结论:数字化模型结合CBCT 3D模型的三维牙颌模型治疗下颌阻生异位尖牙,更有助于缩短患者的矫治时间,减少邻近切牙牙根吸收,矫治效果良好。 展开更多
关键词 下颌阻生尖牙 锥形束CT 数字化3D模型 三维牵引钩导板
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APPLICATION OF IMPROVED EMD IN VIBRATION SIGNAL FEATURE EXTRACTION OF VEHICLE
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作者 辛江慧 安木金 +1 位作者 张雨 任成龙 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2012年第2期193-198,共6页
In order to truly obtain the feature extraction of vibration signals under the strong background noise, the analysis and improvement of empirical mode decomposition (EMD) is carried on. After that, the improved EMD ... In order to truly obtain the feature extraction of vibration signals under the strong background noise, the analysis and improvement of empirical mode decomposition (EMD) is carried on. After that, the improved EMD is applied to the feature extraction of vehicle vibration signals. First, the multi-autocorrelation method is adopted in each input signal,so the noise is reduced effectively. Then, EMD is used to deal with these signals,and the intrinsic mode functions (IMFs) are obtained. Finally, for obtaining the feature information of these signals, the Hilbert transformation and the spectrum analysis are performed in some IMFs. Theoretical analysis and ex- periment verify the effectiveness of the method, which are valuable reference for the same engineering problems. 展开更多
关键词 empirical mode decomposition (EMD) vehicle vibration signal multi-autocorrelation feature ex- traction
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软地质条件下履带车辆履带板牵引性能研究
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作者 韩庆珏 潘涛 +2 位作者 肖江铃 晏希 孙继静 《中国农机化学报》 北大核心 2026年第2期249-255,共7页
为优化履带车牵引性能,研究履带板的重要结构参数对履带板牵引性能所造成的影响。基于土壤地面力学理论,对履带板受力情况进行理论分析,确定影响履带车辆牵引性能的履带板结构尺寸参数。通过土力学试验获得软地质土壤特征参数。利用Recu... 为优化履带车牵引性能,研究履带板的重要结构参数对履带板牵引性能所造成的影响。基于土壤地面力学理论,对履带板受力情况进行理论分析,确定影响履带车辆牵引性能的履带板结构尺寸参数。通过土力学试验获得软地质土壤特征参数。利用RecurDyn仿真软件分析履带车辆行驶过程的牵引性能。设计不同结构参数履带板,并在实验室内进行履带板牵引力试验,对比分析不同结构参数对履带板牵引性能的影响。结果表明,增加履刺高度、增加履带板宽度、减小履刺间距均会提升履带板牵引性能,提升最大幅度分别为12.160%、13.106%和7.327%。 展开更多
关键词 履带车辆 履带板 软土地面 牵引性能
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轨道列车节能运行研究综述
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作者 连惠 田志强 +2 位作者 宋琦 靳欣妮 王付霞 《铁道运输与经济》 北大核心 2026年第1期27-45,共19页
轨道列车节能运行是实现交通领域绿色低碳发展的关键举措,对降低运营成本、减少环境污染具有重要意义。研究系统综述了轨道列车节能运行的研究进展,从牵引控制策略、再生制动技术、综合优化策略及智能求解算法4个维度展开分析。研究表明... 轨道列车节能运行是实现交通领域绿色低碳发展的关键举措,对降低运营成本、减少环境污染具有重要意义。研究系统综述了轨道列车节能运行的研究进展,从牵引控制策略、再生制动技术、综合优化策略及智能求解算法4个维度展开分析。研究表明,牵引控制策略通过优化速度曲线和工况转换点实现能耗最小化;再生制动技术通过逆变回馈和储能设备提升能量回收效率;综合优化策略兼顾能耗、准点率和乘客舒适性等多目标平衡;智能求解算法为复杂优化问题提供了高效解决方案。然而,现有研究仍面临动态环境适应性不足、多列车协同优化复杂度高、实时性要求严格等挑战。未来研究应进一步融合人工智能与大数据技术,探索更高效的全局优化方法,推动轨道列车节能运行向智能化、精细化方向发展。 展开更多
关键词 轨道交通列车 节能运行 牵引控制 再生能量 综合优化 求解方法
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引入肌肉单元的脊柱侧弯有限元仿真:双向载荷的矫形效果验证
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作者 武泓序 刘轩宇 +6 位作者 王韬宇 王诗尧 程靖祎 张鸣文 张银霞 刘治华 王晓洁 《中国组织工程研究》 北大核心 2026年第9期2172-2181,共10页
背景:目前脊柱侧弯保守治疗方法主要包括物理治疗、支具矫正、牵引等,在临床实践中,通常在患者的耐受性范围内使用尽可能大的牵引力,并且随着耐受性的增加,牵引力也会增加。目的:在建立脊柱侧弯三维有限元模型的基础上增加肌肉单元使模... 背景:目前脊柱侧弯保守治疗方法主要包括物理治疗、支具矫正、牵引等,在临床实践中,通常在患者的耐受性范围内使用尽可能大的牵引力,并且随着耐受性的增加,牵引力也会增加。目的:在建立脊柱侧弯三维有限元模型的基础上增加肌肉单元使模型更符合实际,探讨具有双向(轴向、横向)矫形载荷的脊柱侧弯矫形装置的治疗效果。通过分析轴向牵引矫形力与横向侧推矫形力之间的相互作用关系,分析矫形力对Cobb角的影响,为患者制定最合适的治疗方案提供理论依据。方法:提取1例35岁脊柱侧弯患者的脊柱CT扫描数据,应用Mimics、Geomagic Wrap和HyperMesh等软件建立三维有限元模型,增加肌肉单元,并通过Abaqus进行有限元分析。分别分析了轴向牵引载荷和横向侧推载荷单独作用以及两者共同作用时的治疗效果,同时研究了周期性横向载荷对治疗效果的影响,并建立了2种载荷的力矩数学模型进行分析计算。结果与结论:①轴向牵引载荷与横向侧推载荷共同作用时,治疗脊柱侧弯的矫形率分别为胸椎段22%、腰椎段24%,优于二者单独作用,且增加周期性横向载荷后,矫形率进一步提高为27%和29%;②两种载荷的作用效果与Cobb角之间存在一定关系,Cobb角小于53.13°时,横向载荷的作用效果优于轴向载荷;Cobb角大于53.13°时,轴向载荷的作用效果优于横向载荷,可为两种矫形力施加的先后顺序提供力学理论依据;③这些结果可为制定脊柱侧弯患者个性化治疗方案提供理论支持,确保矫形力的安全与有效性。 展开更多
关键词 脊柱侧弯 矫形载荷 三维有限元模型 COBB角 生物力学 周期性载荷 横向侧推 轴向牵引 治疗效果
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龙氏牵引下正骨法对颈椎功能单元的力学影响:头颈生物力学模型定量分析
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作者 蔡其锐 戴小玮 +5 位作者 郑晓斌 简思莉 卢绍平 刘特熹 刘国科 林远方 《中国组织工程研究》 北大核心 2026年第9期2208-2216,共9页
背景:龙氏牵引下正骨法治疗神经根型颈椎病的临床疗效确切、应用广泛,但对于其生物力学起效机制尚未有明确报道。目的:基于三维有限元分析技术探讨龙氏牵引下正骨法改善颈椎椎间孔形变的生物力学依据。方法:基于之前开发并验证的耦合头... 背景:龙氏牵引下正骨法治疗神经根型颈椎病的临床疗效确切、应用广泛,但对于其生物力学起效机制尚未有明确报道。目的:基于三维有限元分析技术探讨龙氏牵引下正骨法改善颈椎椎间孔形变的生物力学依据。方法:基于之前开发并验证的耦合头颈部骨骼肌的有限元模型,将模型导入LS-DYNA软件,分别对经典颈椎牵引与龙氏牵引下正骨法的3个手法(推正法、扳按法及摇正法)进行仿真模拟。C5作为目标节段,设置相关边界条件,在200 N牵引力的前提下,先后对颈椎施加向前、向左下拉力及向左侧轴向旋转的扭矩以模拟手法实施,记录分析椎间孔相对位移、相对角度、侧屈位移、椎间盘位移方向及应变。结果与结论:①推正法对椎间孔的相对位移作用最为显著,其中C5的位移可达15.6 mm,导致椎间孔容积增大;此外,椎间孔的相对角度变化整体更为明显,峰值可达22.9°;②在整体节段侧屈相对位移的改变中,摇正法产生的位移为扳按法的2.4倍,而推正法与经典颈椎牵引在椎体侧屈位移的改变上较为细微;③各正骨手法下的椎间盘位移方向均表现为向前,推正法、扳按法和摇正法在Y轴方向的位移分别为11.56,9.94和7.73 mm;④正骨手法使椎间盘产生向前的滑移应变,释放了后方受压节段的椎间孔容积;⑤相对而言,经典颈椎牵引对上述改变的效果不如正骨手法显著,无法达到相同程度的改变;⑥因此,龙氏牵引下正骨法相对于经典颈椎牵引更能够增大颈椎椎间孔间隙,改善椎间孔形变,原因在于其增加了颈椎椎间孔相对位移、相对角度和侧屈位移,增大了椎间盘位移并产生向前应变,从而使责任节段的神经得到释放,缓解其症状,达到良好的治疗效果。 展开更多
关键词 龙氏牵引下正骨法 神经根型颈椎病 椎间孔容积 有限元分析 生物力学 相对位移 相对角度 椎间盘应变
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不同松质骨体积分数影响股骨颈骨折裂纹扩展的有限元分析
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作者 杜传佳 焦姣 +6 位作者 周继和 王帅 刘国辉 王杨 尚画雨 王慧明 张晓沛 《中国组织工程研究》 北大核心 2026年第15期3753-3759,共7页
背景:股骨颈骨折是老年人群中常见且具有高度危害性的骨折类型,其发生率随着年龄增长而显著增加。目前,股骨颈骨折的损伤机制尚未完全明确,尤其是在力学表征、裂纹萌生及失效机制等方面。目的:采用有限元法分析不同松质骨体积分数对股... 背景:股骨颈骨折是老年人群中常见且具有高度危害性的骨折类型,其发生率随着年龄增长而显著增加。目前,股骨颈骨折的损伤机制尚未完全明确,尤其是在力学表征、裂纹萌生及失效机制等方面。目的:采用有限元法分析不同松质骨体积分数对股骨颈裂纹扩展的影响,为深入探析股骨颈骨折的力学机制提供理论支持。方法:将1例健康志愿者的股骨近端CT数据导入Mimics 19.0进行三维重建,构建含有皮质骨、松质骨股骨近端模型,导入ABAQUS/CAE 2021中赋予材料参数,并使用随机批量删除单元Python脚本,构建35%,30%,25%和20%松质骨体积分数股骨近端有限元模型,结合内聚力模型分析在2 mm轴向位移载荷作用下股骨颈骨折的力学响应及其损伤机制。结果与结论:①与35%松质骨体积分数模型相比,20%松质骨体积分数模型的承载力下降10.02%,表明松质骨体积分数减小会削弱股骨颈的力学性能,增加骨折风险;②剪切失效单元/总失效单元最大比值均在90%以上,高速轴向冲击载荷下剪切失效主导股骨颈骨折的形成;③结果表明,松质骨体积分数减小明显削弱了股骨颈的力学性能,增加骨折风险;高速轴向冲击载荷下股骨颈骨折机制以剪切失效为主。 展开更多
关键词 股骨颈 松质骨体积分数 骨质疏松症 骨折 有限元法 生物力学 内聚力模型 内聚力模型牵引-分离准则 裂纹扩展
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基于概率Petri网的牵引系统功能故障实时诊断
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作者 李启明 成正林 +2 位作者 李学明 陈志文 刘建华 《湖南工业大学学报》 2026年第1期33-39,共7页
针对列车运行途中牵引系统报出功能故障后无法实时精准定位故障源的难题,提出了一种基于概率Petri网的实时诊断方法。通过挖掘功能故障相关故障源与工况事件间的动态时序变化规律,建立了各种故障源对应的概率Petri网模型,并基于实时计... 针对列车运行途中牵引系统报出功能故障后无法实时精准定位故障源的难题,提出了一种基于概率Petri网的实时诊断方法。通过挖掘功能故障相关故障源与工况事件间的动态时序变化规律,建立了各种故障源对应的概率Petri网模型,并基于实时计算模型输出概率值进行诊断决策,实现了功能故障的快速精准定位。基于逆变过流故障的现场案例数据测试表明,所提方法能实现导致逆变过流的6类典型故障源精准定位,诊断响应时间小于0.1 s。相较于阈值检测与离线诊断方法,所提方法通过动态权重调整与并发故障概率叠加,显著提升了非平稳工况下的诊断实时性与鲁棒性,为牵引传动系统功能故障的实时诊断与差异化保护策略实施提供了有效的解决方案。 展开更多
关键词 牵引传动系统 功能故障 概率Petri网 工况事件 实时诊断
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