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Clinical outcomes of humeral shaft fractures managed with intramedullary K-wires:A closed reduction approach
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作者 Mohammad Adham Abdulsamad Turki S AlMugren +6 位作者 Abdullah I Saeed Waleed A Alrogy Linah D Alanazi Ohud M Alsaqer Faisal T Alanbar Abdulrahman H Alfarraj Ziad A Aljaafri 《World Journal of Orthopedics》 2026年第1期57-66,共10页
BACKGROUND Humeral shaft fractures are common and vary by age,with high-energy trauma observed in younger adults and low-impact injuries in older adults.Radial nerve palsy is a frequent complication.Treatment ranges f... BACKGROUND Humeral shaft fractures are common and vary by age,with high-energy trauma observed in younger adults and low-impact injuries in older adults.Radial nerve palsy is a frequent complication.Treatment ranges from nonoperative methods to surgical interventions such as intramedullary K-wires,which promote faster rehabilitation and improved elbow mobility.AIM To evaluate the outcomes of managing humeral shaft fractures using closed reduction and internal fixation with flexible intramedullary K-wires.METHODS This was a retrospective cohort study analyzing the medical records of patients with humeral shaft fractures managed with flexible intramedullary K-wires at King Abdulaziz Medical City,using non-random sampling and descriptive analysis for outcome evaluation.RESULTS This study assessed the clinical outcomes of 20 patients treated for humeral shaft fractures with intramedullary K-wires.Patients were predominantly male(n=16,80%),had an average age of 39.2 years,and a mean body mass index of 29.5 kg/m^(2).The fractures most frequently occurred in the middle third of the humerus(n=14,70%),with oblique fractures being the most common type(n=7,35%).All surgeries used general anesthesia and a posterior approach,with no intraoperative complications reported.Postoperatively,all patients achieved clinical and radiological union(n=20,100%),and the majority(n=13,65%)reached an elbow range of motion from 0 to 150 degrees.CONCLUSION These results suggest that intramedullary K-wire fixation may be an effective option for treating humeral shaft fractures,with favorable outcomes in range of motion recovery,fracture union,and a low rate of intraoperative complications. 展开更多
关键词 Humeral shaft fractures Flexible intramedullary K-wires Clinical outcomes Range of motion Surgical management
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Experimental study and numerical analysis on bearing behaviors of super-long rock-socketed bored pile groups 被引量:3
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作者 高睿 胡念 朱斌 《Journal of Southeast University(English Edition)》 EI CAS 2010年第4期597-602,共6页
A centrifuge modeling test and a three-dimensional finite element analysis(FEA)of super-long rock-socketed bored pile groups of the Tianxingzhou Bridge are proposed.Based on the similarity theory,different prototypi... A centrifuge modeling test and a three-dimensional finite element analysis(FEA)of super-long rock-socketed bored pile groups of the Tianxingzhou Bridge are proposed.Based on the similarity theory,different prototypical materials are simulated using different indicators in the centrifuge model.The silver sand,the shaft and the pile cap are simulated according to the natural density,the compressive stiffness and the bending stiffness,respectively.The finite element method(FEM)is implemented and analyzed in ANSYS,in which the stress field during the undisturbed soil stage,the boring stage,the concrete-casting stage and the curing stage are discussed in detail.Comparisons in terms of load-settlement,shaft axial force distribution and lateral friction between the numerical results and the test data are carried out to investigate the bearing behaviors of super-long rock-socketed bored pile groups under loading and unloading conditions.Results show that there is a good agreement between the centrifuge modeling tests and the FEM.In addition,the load distribution at the pile top is complicated,which is related to the stiffness of the cap,the corresponding assumptions and the analysis method.The shaft axial force first increases slightly with depth then decreases sharply,and the rate of decrease in rock is greater than that in sand and soil. 展开更多
关键词 super-long rock-socketed pile bored pile groups centrifuge modeling test finite element analysis
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Effect of sediment on vertical dynamic impedance of rock-socketed pile with large diameter 被引量:7
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作者 俞缙 蔡燕燕 吴文兵 《Journal of Central South University》 SCIE EI CAS 2013年第10期2856-2862,共7页
Based on the fictitious soil pile model, the effect of sediment on the vertical dynamic impedance of rock-socketed pile with large diameter was theoretically studied by means of Laplace transform technique and impedan... Based on the fictitious soil pile model, the effect of sediment on the vertical dynamic impedance of rock-socketed pile with large diameter was theoretically studied by means of Laplace transform technique and impedance function transfer method. Firstly, the sediment under rock-socketed pile was assumed to be fictitious soil pile with the same sectional area. The Rayleigh-Love rode model was used to simulate the rock-socketed pile and the fictitious soil pile with the consideration of the lateral inertial effect of large-diameter pile. The layered surrounding soils and bedrock were modeled by the plane strain model. Then, by virtue of the initial conditions and boundary conditions of the soil pile system, the analytical solution of the vertical dynamic impedance at the head of rock-socketed pile was derived for the arbitrary excitation acting on the pile head. Lastly, based on the presented analytical solution, the effect of sediment properties, bedrock property and lateral inertial effect on the vertical dynamic impedance at rock-socketed pile head were investigated in detail. It is shown that the sediment properties have significant effect on the vertical dynamic impedance at the rock-socketed pile head. The ability of soil-pile system to resist dynamic vertical deformation is weakened with the increase of sediment thickness, but amplified with the increase of shear wave velocity of sediment. The ability of soil pile system to resist dynamic vertical deformation is amplified with the bedrock property improving, but the ability of soil-pile system to resist vertical vibration is weakened with the improvement of bedrock property. 展开更多
关键词 rock-socketed PILE SEDIMENT dynamic impedance fictitious soil PILE MODEL large DIAMETER Rayleigh-Love rode MODEL
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Ultimate end bearing capacity of rock-socketed pile based on generalized nonlinear unified strength criterion 被引量:7
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作者 章敏 王星华 汪优 《Journal of Central South University》 SCIE EI CAS 2011年第1期208-215,共8页
In order to study the mechanism of bearing behavior at the tip of a pile embedded in rock, the generalized nonlinear unified strength criterion and slip line principle for resolving the differential equation systems w... In order to study the mechanism of bearing behavior at the tip of a pile embedded in rock, the generalized nonlinear unified strength criterion and slip line principle for resolving the differential equation systems which govern the stress field were applied to derive the ultimate end beating capacity based on some reasonable hypothesis and failure plane model. Both numerical simulation and test results were compared with the theoretic solution. The results show good consistency with each other and verify the validity of the present approach. The depth effect with respective to embedment ratio and other influence factors like geological strength index, intermediate principal stress, overburden factor, and damage on end bearing capacity were discussed in the analytical solution. The results show that the proposed yield criterion can be much better for investigating the ultimate end bearing performance of rock-socketed pile. The end bearing capacity increases with embedment ratio and the increasing degree is influenced intensely by the above parameters. Furthermore, ignoring intermediate stress effect would underestimate the strength properties of the rock material and lead to a very conservative estimation value. 展开更多
关键词 rock-socketed pile generalized nonlinear unified strength criterion slip line principle embedment ratio damage endbearing capacity
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Buckling analysis of super-long rock-socketed filling piles in soft soil area by element free Galerkin method 被引量:2
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作者 邹新军 赵明华 刘光栋 《Journal of Central South University of Technology》 EI 2007年第6期858-863,共6页
In order to discuss the buckling stability of super-long rock-socketed filling piles widely used in bridge engineering in soft soil area such as Dongting Lake, the second stability type was adopted instead of traditio... In order to discuss the buckling stability of super-long rock-socketed filling piles widely used in bridge engineering in soft soil area such as Dongting Lake, the second stability type was adopted instead of traditional first type, and a newly invented numerical analysis method, i.e. the element-free Galerkin method (EFGM), was introduced to consider the non-concordant deformation and nonlinearity of the pile-soil interface. Then, based on the nonlinear elastic-ideal plastic pile-soil interface model, a nonlinear iterative algorithm was given to analyze the pile-soil interaction, and a program for buckling analysis of piles by the EFGM (PBAP-EFGM) and arc length method was worked out as well. The application results in an engineering example show that, the shape of pile top load-settlement curve obtained by the program agrees well with the measured one, of which the difference may be caused mainly by those uncertain factors such as possible initial defects of pile shaft and the eccentric loading during the test process. However, the calculated critical load is very close with the measured ultimate load of the test pile, and the corresponding relative error is only 5.6%, far better than the calculated values by linear and nonlinear incremental buckling analysis (with a greater relative error of 37.0% and 15.4% respectively), which also verifies the rationality and feasibility of the present method. 展开更多
关键词 super-long rock-socketed filling pile buckling analysis element free Galerkin method critical load
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Hydraulic characteristics of a large rotation-angle baffle-drop shaft through synergetic discharge from dry and wet sides 被引量:1
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作者 Pei-de Liang Jun Chen +1 位作者 Teng Wu Jing Yan 《Water Science and Engineering》 2025年第1期115-124,共10页
To enhance the operational capacity and space utilization of baffle-drop shafts,this study improved the traditional baffle-drop shaft by expanding the wet-side space,incorporating large rotation-angle baffles,and inst... To enhance the operational capacity and space utilization of baffle-drop shafts,this study improved the traditional baffle-drop shaft by expanding the wet-side space,incorporating large rotation-angle baffles,and installing overflow holes in the dividing wall.A three-dimensional turbulent model was developed using ANSYS Fluent to simulate the hydraulic characteristics of both traditional and new baffle-drop shafts across various flow rates.The simulation results demonstrated that the new shaft design allowed for discharge from both the wet and dry sides,significantly improving operational capacity,with the dry side capable of handling 40%of the inlet flow.Compared to the traditional shaft,the new design reduced shaft wall pressures and decreased the mean and standard deviation of pressure on typical baffles by 21%and 63%,respectively,therefore enhancing structural safety.Additionally,the new shaft achieved a 2%-12%higher energy dissipation rate than the traditional shaft across different flow rates.This study offers valuable insights for the design and optimization of drop shafts in deep tunnel drainage systems. 展开更多
关键词 Baffle-drop shaft Synergetic discharge Fluent Numerical simulation Hydraulic characteristics
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A review on production and application of direct reduced iron in gas-based shaft furnace–electric arc furnace route 被引量:1
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作者 Ling-zhi Yang Zeng Feng +4 位作者 Hang Hu Guang-sheng Wei Bo-tao Xue Yu-feng Guo Tao Jiang 《Journal of Iron and Steel Research International》 2025年第3期485-518,共34页
The iron and steel industry,standing as a quintessential manufacture example with high consumption,pollution and emissions,faces significant environmental and sustainable development challenges.Electric arc furnace(EA... The iron and steel industry,standing as a quintessential manufacture example with high consumption,pollution and emissions,faces significant environmental and sustainable development challenges.Electric arc furnace(EAF)steelmaking process mainly uses scrap as raw material and is characterized by environmentally friendly and recyclable process.However,the further development of EAF route in China is limited by the reserve,supply,availability and quality of scrap resource.Direct reduced iron(DRI)is one of typical low-carbon and clean charges,which can effectively make up for the adverse effects caused by the lack of scrap.The physical and chemical properties,classifications,and production technologies of DRI are firstly reviewed.In particular,the reducing gas types,reduction temperature,and reduction mechanism of the DRI production with gas-based shaft furnace(SF)technology are detailed.Considering the crucial role played by DRI application in EAF,the influences of DRI addition on EAF smelting rules and operations including the blending and charging process,heat transfer and melting in molten bath,slag formation operation,refractory corrosion,and slag system evolution are then further discussed.Finally,the comparative analysis and assessment of the consumption level of material and energy as well as the cleaner production both covering the clean chemical composition of molten steel and the clean environment impact in EAF steelmaking with DRI charged are conducted.From perspectives of metallurgical process engineering,a suitable route of hydrogen generation and application(from coke oven gas,methanol,and clean energy power),CO_(2) capture and utilization integrated with SF–EAF process is proposed.In view of the difficulties in large-scale DRI application in EAF,the follow-up work should focus on the investigation of DRI charging and melting,slag system evolution and molten pool reaction rules,as well as the developments of the DRI standardized use technology and intelligent batching and control models. 展开更多
关键词 Electric arc furnace steelmaking Direct reduced iron Hydrogen-based shaft furnace Sustainable production Low-carbon development
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Effects of shaft and tunnel portal on coupled aerodynamic characteristics of 600 km/h superconducting maglev train
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作者 PAN Shen-gong ZHANG Lei +3 位作者 WANG Tian-tian YU Qing-song LIN Tong-tong XU Shu 《Journal of Central South University》 2025年第12期4955-4967,共13页
To address the severe aerodynamic effects caused by a 600 km/h superconducting maglev train passing through a tunnel at full speed,this study systematically investigates the coupled influence of auxiliary facility par... To address the severe aerodynamic effects caused by a 600 km/h superconducting maglev train passing through a tunnel at full speed,this study systematically investigates the coupled influence of auxiliary facility parameters including the shaft(location L,cross sectional dimension W,height h),tunnel portal(cross sectional area S),and openings(spacing D,side length F)on the evolution of tunnel aerodynamic effects.By integrating three dimensional unsteady flow field numerical simulations with a dynamic model testing system,the research notably reveals the regulatory mechanisms of these parameters on the evolution characteristics of the initial compression wave pressure gradient and the multi peak structure of micro-pressure waves.The results show that shaft parameters significantly affect the initial compression wave.Both the wave amplitude and gradient exhibit a linear negative correlation with cross sectional dimension W and a linear positive correlation with location L,while demonstrating a nonlinear relationship with height h,the amplitude follows a cubic polynomial trend,and the gradient initially increases before plateauing.Under the configuration W=8 m,L=50 m,and h=20 m,substantial reductions in both compression wave amplitude and gradient were achieved.The portal cross sectional area S shows a"U-shaped"relationship with the compression wave gradient,with the maximum gradient reduction of 53.24%occurring at S=210 m^(2),a result comparable to that achieved with optimized opening parameters(D=15 m,F=3.5 m,53.96%).Regarding micro-pressure waves,the amplitude measured 20 m from the tunnel exit shows a linear positive correlation with shaft parameters L and W,while the influence of h saturates beyond 50 m.Reductions exceeding 54%were achieved with portal parameters,either at S=210 m^(2) or using the optimized opening configuration.Furthermore,micro-pressure waves near the portal exhibit a consistent dual peak structure:the first peak originates from the train entry compression wave,and the second results from further wave compression after tunnel exit.The opening location governs selective peak regulation openings near the portal entrance primarily suppress the first peak with minimal impact on the second,whereas centrally located openings reduce the first peak but can amplify the second by up to 3%.Based on these insights,an optimized parameter configuration is proposed:a shaft with a cross-sectional dimension≥8 m located 50 m from the portal,a portal cross sectional area of 210 m^(2),and openings spaced at 15 m intervals.This configuration can reduce the initial compression wave gradient by over 50%.The results provide a theoretical foundation for controlling aerodynamic effects of superconducting maglev train. 展开更多
关键词 superconducting maglev train shaft tunnel portal initial compression wave pressure gradient micro pressure wave
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Unusual Complication of Flexible Intramedullary Nail in Pediatric Femoral Shaft Fracture
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作者 Alwen Arong Juan Alejandro Legaspi Wesson Pious A. Espiritu 《Open Journal of Orthopedics》 2025年第2期78-87,共10页
Background of the Study: Femoral shaft fracture is the most common pediatric injury requiring hospitalization. For children less than 5 years old, non-surgical approach is recommended. For pediatric patients 5 - 14 ye... Background of the Study: Femoral shaft fracture is the most common pediatric injury requiring hospitalization. For children less than 5 years old, non-surgical approach is recommended. For pediatric patients 5 - 14 years old, the most common mode of treatment is flexible intramedullary nailing with a known complication of pain at post-op site, inflammatory reaction/bursitis at the entry site, superficial and deep infection, knee synovitis, knee stiffness, leg length discrepancy, proximal nail migration, angulation or malunion, delayed and non-union, implant breakage. This study aims to present a rare complication of a femoral fracture fixed with flexible intramedullary nail. Methodology: We report the outcome of a 12-year-old male with peri implant fracture of the left femur. He underwent removal of plates and screws and subsequently fixed with flexible intramedullary nails. Patient was followed up at 1, 3, 7, and 10 months post-operatively. Varus-valgus, sagittal angulation, and limb shortening were measured pre- and post-operatively. Complications were recorded on each visit. Results: Pre-operative varus angulation was 10˚, pro-curvatum of 55˚ with limb shortening of 4 cm. Postoperatively, varus was maintained to 10˚ but pro-curvatum was corrected to 4˚ and limb shortening was reduced to 1 cm. However, after 1 month the varus angulation increased to 30˚ while maintaining sagittal pro-curvatum. Limb shortening also increased to 2 cm. New bone formation started to appear along the mechanical axis of the left femur which is apparent at 3 months post-op and pro-curvatum increased to 20˚. At 7 and 10 months post-op no signs of union was noted at the fracture site but the callus formation along the mechanical axis gradually matured and appeared as a new femoral shaft. Conclusion: Formation of new bone in response to unstable flexible intramedullary fixation in pediatric femoral shaft fracture is a very rare complication. 展开更多
关键词 Elastic Stable Intramedullary Nail Wolff’s Law Pediatric Femur Fracture Pediatric Orthopaedic Femoral shaft Fracture
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A ballistic impact identification method for the helicopter tail drive shaft system based on vibration response analysis
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作者 Chao ZHANG Meijun LIAO +5 位作者 Xiaoyu CHE Hu YU Yifei CAI Rupeng ZHU Weifang CHEN Dan WANG 《Chinese Journal of Aeronautics》 2025年第8期259-282,共24页
The ballistic impact identification method for the helicopter Tail Drive Shaft System(TDSS)isn't yet comprehensive,which affects helicopter flight safety.This paper proposes a ballistic impact identification metho... The ballistic impact identification method for the helicopter Tail Drive Shaft System(TDSS)isn't yet comprehensive,which affects helicopter flight safety.This paper proposes a ballistic impact identification method for the TDSS based on vibration response analysis.Based on the Johnson-Cook constitutive model and failure criteria,the ballistic impact finite element simulation model is established,which is verified by the ballistic impact experiment of the Tail Drive Shaft(TDS).Considering the ballistic impact excitation force,the dynamic model of the TDSS with ballistic impact is established,which is verified by finite element commercial software.If a bullet hits the TDS,the bending vibration displacement increases sharply at a certain moment and then significantly increases but remains stable.Meanwhile,the critical speed component appears in the frequency-domain response of bending vibration,and then the speed component significantly increases but remains stable.What's more,the axis trajectory exhibits a sudden,large-scale,and irregular whirling motion at a certain moment,followed by a significant increase but remains stable.Furthermore,if the axial vibration response is small,the bullet core shooting should be considered vertically or at a small incident angle,otherwise,it should be considered at a large incident angle. 展开更多
关键词 BALLISTIC DYNAMICS Helicopters shaft system Vibration analysis
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Forming characteristics of bi-metallic composite shafts by cross-wedge rolling
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作者 Jun-ling Li Jia-long Lu +4 位作者 Ao Wang Le Zhu Chao-yang Sun Bao-yu Wang Zhi-gang Li 《Journal of Iron and Steel Research International》 2025年第9期2820-2833,共14页
To address the increasing demand for corrosion-resistant shaft components,a bi-metallic composite shaft comprising carbon steel,which is known for its high thermal strength,and stainless cladding,which offers excellen... To address the increasing demand for corrosion-resistant shaft components,a bi-metallic composite shaft comprising carbon steel,which is known for its high thermal strength,and stainless cladding,which offers excellent corrosion resistance,was introduced.A novel method for manufacturing these composite shaft parts using cross-wedge rolling(CWR)was proposed and explored.Thermal simulation experiments,CWR forming trials and finite element analysis were conducted to examine the coordinated deformation during the CWR process.The results revealed a downhill diffusion pattern of elements from higher to lower-concentration areas,forming a smooth and uniform concentration gradient.When the cladding thickness(CT)ranged from 3 to 4 mm,the trajectories of the points on both the cladding material and the substrate coincided,indicating strong bonding at the transitional interface of the composite shaft.Conversely,with a CT of 5 mm,coordinated deformation between the substrate and cladding material was not achieved.Shear strength tests demonstrated a gradual decrease in strength with increasing CT.The microscopic morphology of the interface showed that the metal grains near both sides of the interface were refined,and the binding interface displayed a slightly curved shape.A viable method was provided for producing high-performance corrosion-resistant composite shaft components using CWR technology. 展开更多
关键词 Cross-wedge rolling Bi-metallic shaft Elemental diffusion Shear strength
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Self-reforming of coke oven gas in gas-based shaft furnace: thermodynamic analysis and reforming mechanism
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作者 Chen-mei Tang Shu-bing Shi +4 位作者 Jian Pan De-qing Zhu Zheng-qi Guo Cong-cong Yang Si-wei Li 《Journal of Iron and Steel Research International》 2025年第10期3249-3261,共13页
The self-reforming of coke oven gas(COG)in a gas-based shaft furnace was investigated,employing metallized iron as a catalyst.Thermodynamic analyses,supported by FactSage 8.3 calculations and regression modeling,were ... The self-reforming of coke oven gas(COG)in a gas-based shaft furnace was investigated,employing metallized iron as a catalyst.Thermodynamic analyses,supported by FactSage 8.3 calculations and regression modeling,were used to investigate the effects of temperature(700–1100℃),CO_(2)(3%–10%),and H_(2)O(1%–9%)concentrations on CH_(4) conversion efficiency.Results indicate that CH_(4) conversion exceeds 90%at temperatures above 1000℃,with CO_(2) and H_(2)O concentrations at 9%and 5%,respectively.During the reforming process,introducing CO_(2) provides additional oxygen,facilitating the oxidation of CH_(4),while H_(2)O enhances H_(2) production through the steam reforming pathway.Experimental findings reveal a CH_(4) conversion of 85.83%with a H_(2)/CO ratio of 5.44 at 1050℃.In addition,an optimal H_(2)O concentration of 6%yields the highest CH_(4) conversion of 84.24%,while CO_(2) exhibits minimal effects on promoting the reforming process.Increasing the metallization rate of pellets from 43%to 92%significantly enhances CH_(4) reforming.This is mainly due to the fact that metallized iron is vital in promoting CH_(4) dissociation and improving syngas yield by providing active sites for the redox cycle of CO_(2) and H_(2)O. 展开更多
关键词 Hydrogen metallurgy Gas-based shaft furnace Coke oven gas Self-reforming Reforming mechanism
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Influence of diversion cone structure on inner characteristic in hydrogen-enriched shaft furnace:a DEM study
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作者 Xu Tian Heng Zhou +5 位作者 Tian Xia Zhi-tao Qin Hui-dong Guo Da-wei Sun Ming-yin Kou Sheng-li Wu 《Journal of Iron and Steel Research International》 2025年第7期1844-1855,共12页
The hydrogen-enriched direct reduction shaft furnace addresses the high CO_(2) emissions associated with the blast furnace process.A discrete element method(DEM)model was introduced to explore how the structure of the... The hydrogen-enriched direct reduction shaft furnace addresses the high CO_(2) emissions associated with the blast furnace process.A discrete element method(DEM)model was introduced to explore how the structure of the diversion cone affects particle descent behavior in a hydrogen-enriched shaft furnace.The results indicated that in the absence of a diversion cone,the descending velocity near the furnace wall zone is significantly lower than that at its center,resulting in a‘V’-shaped burden flow pattern.The discharge velocity has a minor impact on the flow pattern in the shaft furnace.Upon installation of a diversion cone,burden descending velocity becomes more uniform,leading to a‘-’-shaped burden flow pattern.As the bottom of the diversion cone ascends(i.e.,the lower end of the diversion cone is progressively closer to the top),there is an increase in the volume fraction of the dead zone within the shaft furnace.This is particularly evident in the formation of a triangular dead zone at the base of the diversion cone.It is suggested that the lower cone of the bi-conical diversion cone should maintain a sufficient height. 展开更多
关键词 Discrete element method Diversion cone shaft furnace Flow pattern Residence time distribution
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Parallax-free panoramic X-ray imaging combined with minimally invasive plate osteosynthesis for treating proximal humeral shaft fractures
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作者 Wen-Jing Cheng Jing-Shun Lu +2 位作者 Zhou-Shan Tao Jia-Bing Xie Min Yang 《World Journal of Orthopedics》 2025年第5期44-50,共7页
BACKGROUND The objective of this study was to evaluate the use of combined parallax-free panoramic X-ray imaging during surgery by enabling the mobile C-arm with minimally invasive plate osteosynthesis(MIPO)in the man... BACKGROUND The objective of this study was to evaluate the use of combined parallax-free panoramic X-ray imaging during surgery by enabling the mobile C-arm with minimally invasive plate osteosynthesis(MIPO)in the management of proximal humeral shaft fractures.AIM To evaluate parallax-free panoramic X-ray images during surgery.METHODS A retrospective series of 17 proximal humeral shaft fractures were treated using combined parallax-free panoramic X-ray imaging during surgery by enabling the mobile C-arm with MIPO.The operating time and radiation exposure time were recorded,and early postoperative physical therapy and partial weight bearing were encouraged.Patients were followed at regular intervals and evaluated radiographically and clinically.RESULTS The mean operating time and radiation time were 73(range,49-95)minutes and 57(range:36-98)seconds,respectively.No complications occurred during the operation.All fractures healed at an average of 16.9(range:15-23)weeks.The average Constant-Murley score for all the patients was 89.5(range:75-100)points.None of the patients showed symptoms of vascular or nerve damage or wound infection.Three months after the operation,none of the patients developed subacromial impingement syndrome.No loosening or fracture of the implants occurred.The frontal and lateral radiographs showed good alignment.CONCLUSION We consider that MIPO with combined parallax-free panoramic X-ray imaging during surgery is an efficient method for treating proximal humeral shaft fractures,and could significantly reduce operative morbidity as well as lower the rate of intra-and postoperative complications. 展开更多
关键词 Minimally invasive plate osteosynthesis Proximal humeral shaft fractures Panoramic X-ray images COMPLICATIONS
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Water pressure relief treatment for protecting the initial support of inclined shafts at high water pressures
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作者 Yu Zhang Fei Tan +3 位作者 Rui Liu Haijun Zhu Xiaorui Wang Yuyong Jiao 《Journal of Rock Mechanics and Geotechnical Engineering》 2025年第10期6468-6481,共14页
The safety of the initial support during the construction of inclined shafts in tunnels traversing through high-hydraulic-pressure surrounding rocks is paramount.This study examines a high-hydraulic-pressure inclined ... The safety of the initial support during the construction of inclined shafts in tunnels traversing through high-hydraulic-pressure surrounding rocks is paramount.This study examines a high-hydraulic-pressure inclined shaft of a tunnel in Western Sichuan Province to analyze the damage characteristics of the initial support and propose a radial drainage and decompression treatment method.Field monitoring was conducted to assess the load and deformation of the initial support structure,and on-site investigations identified the distribution of cracked areas.In addition,numerical simulations were performed to evaluate the force and deformation characteristics of the initial support structure,which were then compared with field observations for validation.The variations in the lateral pressure coefficient and water pressure were evaluated.The results revealed that damage was primarily concentrated in the shoulder,spring line,and knee areas,with the bending moment at the knee increasing by up to 66.9%.The application of the radial drainage and decompression treatment method effectively reduced water pressure loads on the initial support.Post-treatment analysis indicated significant reductions in axial force and bending moment,enhancing structural stability.These findings provide valuable insights for improving the safety and durability of initial support systems in inclined shafts of high-hydraulicpressure railroad tunnels. 展开更多
关键词 TUNNEL Inclined shaft High water pressure Initial support failure treatment Lateral pressure coefficient Numerical model
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Effects of middle air shaft and bypass duct on aerodynamic pressure of platform screen doors in high-speed subway stations
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作者 ZHANG Xu ZHOU Yuan-long +2 位作者 BI Hai-quan WANG Hong-lin YU Nan-yang 《Journal of Central South University》 2025年第12期4940-4954,共15页
The aerodynamic pressure disturbances induced by middle air shafts and bypass ducts in subway tunnels pose significant challenges to enhancing train operational speeds.A comprehensive series of full-scale experiments ... The aerodynamic pressure disturbances induced by middle air shafts and bypass ducts in subway tunnels pose significant challenges to enhancing train operational speeds.A comprehensive series of full-scale experiments are employed to examine the impact of these structural elements on the aerodynamic pressure characteristics of platform screen doors(PSDs)in high-speed subway stations.The experimental results reveal that peak pressures manifest on PSDs surfaces during two distinct scenarios in high-speed subway systems equipped with middle air shafts.One is compression pressure waves propagated from trains traversing the air shaft,and the other is train nearby flow when trains pass the PSDs directly.The peak positive pressures caused by train passing PSDs are much greater than compression pressure waves.Closing middle air shaft can reduce the passing pressure waves.The installation of bypass ducts at overtaking station entrances effectively mitigates peak negative pressures during train-PSD interactions,achieving a maximum reduction efficiency of 8%.These findings provide valuable insights for optimizing the structural design of high-speed subway tunnel systems. 展开更多
关键词 subway station platform screen door aerodynamic pressure measurement middle air shaft bypass duct
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Revisiting the debate on operative vs nonoperative management of humeral shaft fractures
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作者 Yu-Fei Yuan Jie Miao 《World Journal of Orthopedics》 2025年第4期1-4,共4页
Operative management of humeral shaft fractures demonstrates superior early functional recovery(6-month Disabilities of the Arm,Shoulder,and Hand scores)and significantly lower nonunion rates(63.9%reduction)compared t... Operative management of humeral shaft fractures demonstrates superior early functional recovery(6-month Disabilities of the Arm,Shoulder,and Hand scores)and significantly lower nonunion rates(63.9%reduction)compared to functional bracing,particularly in complex cases,while conservative treatment remains viable for low-demand patients.Surgical techniques,including open reduction internal fixation,intramedullary nailing,and minimally invasive plate osteosynthesis,offer trade-offs between anatomic precision and complication risks(e.g.,radial nerve injury vs rotator cuff damage),with over 90%of radial nerve injuries resolving spontaneously.Ultrasound-guided diagnosis(89%sensitivity,95%specificity)optimizes decision-making for nerve entrapment.Individualized treatment selection,prioritizing fracture complexity and patient needs,is critical to balance accelerated rehabilitation with minimized complications. 展开更多
关键词 OPERATIVE NONOPERATIVE Functional brace Humeral shaft fractures Disabilities of the Arm Shoulder and Hand
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Manufacturing and thermal properties of steel-carbon fibre/polyetheretherketone(CF/PEEK)hybrid shafts using laser-assisted in-situ consolidation
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作者 Zequan DING Congcong LUAN +7 位作者 Xinhua YAO Lingyu CHENG Yuyang JI Chengcheng NIU Ningguo DONG Kai ZHAO Zhibin RUAN Jianzhong FU 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 2025年第10期917-930,共14页
A novel steel–carbon fibre/polyetheretherketone(CF/PEEK)hybrid shaft is proposed,considering the thermal stability,negative coefficient of thermal expansion in fibre orientation,and high stiffness of CF/PEEK,which is... A novel steel–carbon fibre/polyetheretherketone(CF/PEEK)hybrid shaft is proposed,considering the thermal stability,negative coefficient of thermal expansion in fibre orientation,and high stiffness of CF/PEEK,which is expected to suppress the thermal deformation of shafts.A laser-assisted in-situ consolidation(LAC)process,together with its equipment,was developed to manufacture the hybrid shaft.Firstly,the optimal process parameters,including the laser-heated temperature and placement speed,were investigated.A maximum short-beam shear strength of 80.7 MPa was achieved when the laser-heated temperature was 500°C and the placement speed was 100 mm/s.In addition,the failure modes and the effect of environmental temperature on the CF/PEEK samples were analyzed.Both interlayer cracks and inelastic deformation failure modes were observed.The formation and propagation of cracks were further investigated through digital image correlation(DIC).Furthermore,internal defects of the CF/PEEK sample were detected using X-ray tomography scans,and a minimum porosity of 0.23%was achieved with the optimal process parameters.Finally,two steel–CF/PEEK hybrid shafts,with different fibre orientations,were manufactured based on the optimal process parameters.The surface temperature distributions and thermal deformations were investigated using a self-established deformation/temperature measurement platform.The hybrid shaft showed an 85.7%reduction in radial displacement with hoop fibre orientation and an 11.5%reduction in axial displacement with cross fibre orientation compared with the steel shaft.The results indicate that the proposed method has great potential to improve the thermal stability of hybrid shafts and the accuracy of machine tools. 展开更多
关键词 Thermal characteristics Steel-carbon fibre/polyetheretherketone(CF/PEEK)hybrid shaft Laser-assisted in-situ consolidation(LAC) Thermal deformation
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基于迁移学习的轴承负荷与变位关系建模研究
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作者 邓义斌 包鹏 朱汉华 《中国舰船研究》 北大核心 2026年第1期314-320,共7页
[目的]为深入研究基于迁移学习的轴承负荷与变位关系的建模动态过程,[方法]以某多支撑轴系作为研究对象,分析建模关键要素,并针对迁移知识准确性、迁移策略适配性及目标数据样本准确性等3个因素来设计正交试验方案,开展基于迁移学习的... [目的]为深入研究基于迁移学习的轴承负荷与变位关系的建模动态过程,[方法]以某多支撑轴系作为研究对象,分析建模关键要素,并针对迁移知识准确性、迁移策略适配性及目标数据样本准确性等3个因素来设计正交试验方案,开展基于迁移学习的建模分析。[结果]结果表明,因素重要性排序为:迁移知识准确性>迁移策略适配性>目标数据样本准确性,在针对迁移学习的建模过程中,应优先考虑迁移知识准确性和迁移策略适配性以快速适配目标域;当目标数据样本准确性在4%以内时,对建模的影响不显著。[结论]研究成果为工程实践中轴承负荷与变位关系的模型构建提供了理论支撑,有助于降低试验成本并提高建模效率。 展开更多
关键词 轴系 轴系校中 迁移学习 轴承负荷 轴承变位 正交试验 建模精度
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西部深厚含水弱胶结基岩钻井法凿井关键技术研究与应用进展
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作者 程桦 姚直书 +5 位作者 荣传新 王宗金 朱建 郭龙辉 王晓云 谢鲍 《煤炭科学技术》 北大核心 2026年第1期35-54,共20页
钻井法在西部深厚含水弱胶结基岩立井井筒施工中得到成功应用,体现了少人、安全、绿色、智能化建井技术发展方向。为解决该工法施工立井井筒出现的工程问题,笔者不断迭代发展钻井法凿井技术,从钻机、刀具刀盘、破岩钻进、井壁结构,以及... 钻井法在西部深厚含水弱胶结基岩立井井筒施工中得到成功应用,体现了少人、安全、绿色、智能化建井技术发展方向。为解决该工法施工立井井筒出现的工程问题,笔者不断迭代发展钻井法凿井技术,从钻机、刀具刀盘、破岩钻进、井壁结构,以及施工工艺等诸多方面,分析存在的关键技术问题,介绍近期国内相应研究与应用进展,提出今后应重点研究方向。关键技术问题:我国现有竖井钻机难以满足西部地层特点及深大井筒施工要求,亟待研发新一代扭矩大、动力足、自动化水平高的大型竖井钻机;穿越西部侏罗系泥质砂岩时,排碴效果差、刀具磨损严重、钻进效率低下、易造浆等;适用于西部地层特性的井壁结构及设计计算方法;深大井筒井壁漂浮下沉过程的稳定性计算等。关键技术研究进展:研制了适应西部深厚含水基岩立井井筒施工的ZMD120/1200新型钻机;以破岩比能和岩石可钻性为特征参数分级指标,提出了侏罗系岩层可钻性分级标准;厘清了排碴流场分布规律及主要影响因素,提出了优化钻头吸碴口结构形式评判指标和方法,揭示了铣齿滚刀分区破岩力学机制。研发了低固相新型泥浆与调控技术,提出了适应西部地区条件的新型高强钻井井壁结构,完善了相应的设计计算方法,制备了大比重壁后充填材料,发展了深大井筒漂浮下沉与壁后充填技术。今后重点研究方向:钻机优化升级与智能化监控、刀盘刀具-排碴参数高效钻进全局优化、西部石炭二叠系地层钻井法凿井技术、西部地区钻井法凿井技术体系和相关标准规范等。 展开更多
关键词 含水弱胶结基岩 钻井法凿井 关键技术 高效钻进
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