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Multi-objective optimization design of anti-roll torsion bar using improved beluga whale optimization algorithm
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作者 Yonghua Li Zhe Chen +1 位作者 Maorui Hou Tao Guo 《Railway Sciences》 2024年第1期32-46,共15页
Purpose – This study aims to reduce the redundant weight of the anti-roll torsion bar brought by thetraditional empirical design and improving its strength and stiffness.Design/methodology/approach – Based on the fi... Purpose – This study aims to reduce the redundant weight of the anti-roll torsion bar brought by thetraditional empirical design and improving its strength and stiffness.Design/methodology/approach – Based on the finite element approach coupled with the improved belugawhale optimization (IBWO) algorithm, a collaborative optimization method is suggested to optimize the designof the anti-roll torsion bar structure and weight. The dimensions and material properties of the torsion bar weredefined as random variables, and the torsion bar’s mass and strength were investigated using finite elements.Then, chaotic mapping and differential evolution (DE) operators are introduced to improve the beluga whaleoptimization (BWO) algorithm and run case studies.Findings – The findings demonstrate that the IBWO has superior solution set distribution uniformity,convergence speed, solution correctness and stability than the BWO. The IBWO algorithm is used to optimizethe anti-roll torsion bar design. The error between the optimization and finite element simulation results wasless than 1%. The weight of the optimized anti-roll torsion bar was lessened by 4%, the maximum stress wasreduced by 35% and the stiffness was increased by 1.9%.Originality/value – The study provides a methodological reference for the simulation optimization process ofthe lateral anti-roll torsion bar. 展开更多
关键词 anti-roll torsion bar Multi-objective optimization IBWO Chaotic mapping Differential evolution
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Effect of Dietary Components on the Shear Bond Strength of Orthodontics Brackets after Thermal Aging
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作者 Philip Punzalan Tanya Al Talib +1 位作者 Anthony Fusco Neamat Hassan Abubakr 《Open Journal of Stomatology》 2024年第6期309-315,共7页
Introduction: The stability of orthodontic brackets throughout orthodontic treatment plays a critical role in the treatment’s effectiveness. The present in vitro study was designed to assess the impact of various die... Introduction: The stability of orthodontic brackets throughout orthodontic treatment plays a critical role in the treatment’s effectiveness. The present in vitro study was designed to assess the impact of various dietary components on the performance of orthodontic brackets. Methods: Metal orthodontic brackets were bonded to 66 extracted anterior teeth divided into groups based on the solution type: Milk, Gatorade, Cold Coffee, and a control group using water. Each group consisted of 20 teeth except for the control group, which included six teeth. The bracketed teeth were submerged in their respective solutions for 15 minutes three times daily at different intervals to mimic an in vivo environment and were stored in artificial saliva at room temperature (23?C). The specimens underwent artificial aging through 10,000 cycles of thermocycling (representing one clinical year) between 5?C and 55?C. Shade measurements were taken using a VITA Easy Shade device, capturing the classic shade and L*, a*, and b* values. Delta E values were calculated immediately post-bonding and after 7 days, 1 month, 1, and 2 clinical years. The shear bond strength of each bracket was measured using an ultra-tester machine. Results: After two clinical years, significant differences in ΔE color values were observed across all groups, with the most substantial change noted in teeth immersed in cold coffee. Brackets submerged in milk demonstrated lower shear bond strength than other solutions, whereas the control group exhibited the highest shear bond strength (P = 0.01). Conclusion: The study indicates that dietary components significantly influence tooth color stability and the shear bond strength of orthodontic brackets, underscoring the importance of considering these factors in orthodontic treatment planning. 展开更多
关键词 Shear Bond Orthodontic brackets Color Stability Thermal Aging
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Research and Analysis on Anti-corrosion of Mountain Photovoltaic Brackets
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作者 Aijun LIN Junwen TANG 《Asian Agricultural Research》 2024年第9期19-22,共4页
With the increasing global demand for renewable energy,solar photovoltaic power generation technology has been widely applied in China and even globally.Especially in mountainous areas,complex terrain resources are cl... With the increasing global demand for renewable energy,solar photovoltaic power generation technology has been widely applied in China and even globally.Especially in mountainous areas,complex terrain resources are cleverly utilized in the construction of photovoltaic power stations,but this also brings severe challenges to the anti-corrosion of photovoltaic brackets.This paper focuses on the anti-corrosion technology of mountain photovoltaic brackets,and deeply explores the influence of natural factors such as mountain climate,sandstorms,and precipitation on the corrosion of photovoltaic brackets.The research results show that the key to improving anti-corrosion performance lies in the selection of bracket materials and optimization of coating processes.After comparing various anti-corrosion treatment methods such as hot-dip galvanizing,spray aluminum coating,and new anti-corrosion materials,it is found that nano coating technology exhibits excellent protective effects in corrosive environments.This study is of great significance for promoting the sustainable development of photovoltaic power generation,providing solid theoretical support and practical guidance for the anti-corrosion design of mountain photovoltaic power stations. 展开更多
关键词 Mountain photovoltaic bracket CORROSION Nano coating
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Application Strategies of the Bracket Set in Modern Architectural Design
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作者 Yajuan Liu 《Journal of Architectural Research and Development》 2024年第2期68-74,共7页
The Bracket Set(dougong)is an important aspect of traditional Chinese architecture known for its exquisite structure,complexity,and rich variations.This design element has been used since the Qin and Han Dynasties and... The Bracket Set(dougong)is an important aspect of traditional Chinese architecture known for its exquisite structure,complexity,and rich variations.This design element has been used since the Qin and Han Dynasties and is still prevalent today.It highlights hierarchy and spiritual connotations in the design of a building.This article explores the application of Bracket Set elements in modern architectural design.It analyzes the specific application strategies of this design element,highlighting its value in modern architecture.The goal is to provide modern architectural designers with multiple perspectives and strategies to fully utilize the advantages of Bracket Set elements in architectural design and enhance the artistic value of their work. 展开更多
关键词 bracket Set elements Architectural design Stressed components Decorative components
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Time-Variant Reliability-Based Multi-Objective Fuzzy Design Optimization for Anti-Roll Torsion Bar of EMU 被引量:7
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作者 Pengpeng Zhi Zhonglai Wang +1 位作者 Bingzhi Chen Ziqiang Sheng 《Computer Modeling in Engineering & Sciences》 SCIE EI 2022年第5期1001-1022,共22页
Although various types of anti-roll torsion bars have been developed to inhibit excessive roll angle of the electric multiple unit(EMU)car body,it is critical to ensure the reliability of structural design due to the ... Although various types of anti-roll torsion bars have been developed to inhibit excessive roll angle of the electric multiple unit(EMU)car body,it is critical to ensure the reliability of structural design due to the complexity of the problems involving time and uncertainties.To address this issue,amulti-objective fuzzy design optimization model is constructed considering time-variant stiffness and strength reliability constraints for the anti-roll torsion bar.A hybrid optimization strategy combining the design of experiment(DoE)sampling and non-linear programming by quadratic lagrangian(NLPQL)is presented to deal with the design optimization model.To characterize the effect of time on the structural performance of the torsion bar,the continuous-time model combined with Ito lemma is proposed to establish the time-variant stiffness and strength reliability constraints.Fuzzy mathematics is employed to conduct uncertainty quantification for the design parameters of the torsion bar.A physical programming approach is used to improve the designer’s preference and to make the optimization results more consistent with engineering practices.Moreover,the effectiveness of the proposed method has been validated by comparing with current methods in a practical engineering case. 展开更多
关键词 anti-roll torsion bar time-variant reliability fuzzy design optimization MULTI-OBJECTIVE
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Research on the influence of action between fin and anti-rolling tank on the integrated stabilization effect 被引量:2
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作者 YU Li-jun JIN Hong-zhang WANG Hui YANG Sheng 《Journal of Marine Science and Application》 2007年第1期9-14,共6页
Through analyzing the roll model of the integrated system of fin and anti-rolling tank, this paper uses binomial equation to simplify the module and check how the approximate parameters simulate the original function.... Through analyzing the roll model of the integrated system of fin and anti-rolling tank, this paper uses binomial equation to simplify the module and check how the approximate parameters simulate the original function. Based on the simplified module, the influence of fin and anti-rolling tank on the coefficient items of the roll module is discussed, and the influencing factors between fin and anti-rolling tank are analysed. And through simulation, the influence of action between fin and anti-rolling tank on the static characteristics, and the integrated stabilization effect, are analyzed. 展开更多
关键词 fin stabilizer anti-rolling tank integrated stabilization action each other INFLUENCE
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Optimization of suspension system of heavy off-road vehicle for stability enhancement using integrated anti-roll bar and coiling spring mechanism 被引量:3
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作者 Ilgar JAVANSHIR Andino MASELENO +1 位作者 Shahin TASOUJIAN Majid OVEISI 《Journal of Central South University》 SCIE EI CAS CSCD 2018年第9期2289-2298,共10页
Short suspension system has an indispensable effect on vehicle handling and ride,so,optimization of vehicle suspension system is one of the most effective methods,which could considerably enhance the vehicle stability... Short suspension system has an indispensable effect on vehicle handling and ride,so,optimization of vehicle suspension system is one of the most effective methods,which could considerably enhance the vehicle stability and controllability.Motion control,stability maintenance and ride comfort improvement are fundamental issues in design of suspension system of off-road vehicles.In this work,a dependent suspension system mostly used in off-road vehicles is modeled using Trucksim software.Then,geometric parameters of suspension system are optimized using integrated anti-roll bar and coiling spring in a way that ride comfort,handling and stability of vehicle are improved.The simulation results of suspension system and variations of geometric parameters due to road roughness and different steering angles are presented in Trucksim and effects of optimization of suspension system during various driving maneuvers in both optimized and un-optimized conditions are compared.The simulation results indicate that the type of suspension system and geometric parameters have significant effect on vehicle performance. 展开更多
关键词 off-road vehicles HANDLING anti-roll bar coil spring vehicle lateral dynamic Trucksim software
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Influence of sway motion on passive anti-rolling tank
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作者 SUN Wei LIANG Li-hua ZHANG Hong 《Journal of Marine Science and Application》 2006年第1期17-22,共6页
The passive anti-rolling tank is one of important ship stabilizers widely used today. But at present, research of the tank is most aimed at its rolling movement. In this paper, the influence of sway motion on the pass... The passive anti-rolling tank is one of important ship stabilizers widely used today. But at present, research of the tank is most aimed at its rolling movement. In this paper, the influence of sway motion on the passive anti-rolling tank is considered, the mathematical model of "ship-passive antl-rolling tank" system coupled with sway motion is developed basing on the U-shaped passive anti-rolling tank theory. Both simulation results and experimental data indicate that it is necessary to consider the influence of sway motion on the anti-rolling tank, which is more agreeable to the actual circumstance. 展开更多
关键词 SHIP ROLLING passive anti-rolling tank sway motion
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Simulation Research on an Active Anti-Roll System for an Air Spring Passenger Car
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作者 张军 李西朝 《Journal of Beijing Institute of Technology》 EI CAS 2008年第1期30-34,共5页
To reduce the roll movement of an air spring passenger car, an active anti-roll system is developed, which is constructed with hydraulic and pneumatic units to change spring rate during cornering. For the comparing re... To reduce the roll movement of an air spring passenger car, an active anti-roll system is developed, which is constructed with hydraulic and pneumatic units to change spring rate during cornering. For the comparing research between the passive and active system, a two-track vehicle model and a co-simulation model of air spring system are built. For the simulation research on the linear movement of the actuator, a mathematical model is considered as dynamical subsystem in the co-simulation model. To active control the roll angle of vehicle body, a sliding-mode controller with optimized control parameters for the test vehicle is introduced into the model. The characteristics of sliding-mode controller is discussed and the validation of active antiroll control is proved by comparison with other control methods. The results show that the roll angle of air spring vehicle is reduced obviously with the active anti-roll actuator in comparison with that of the passive system. Compared with other control methods, sliding-mode controller has an advantage of shortest switching times, which leads to a longer lifetime of actuator and valves. 展开更多
关键词 anti-roll system air spring sliding-mode control active control system vehicle dynamics
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无托槽隐形矫治器扩展上颌牙弓时附件差异对后牙位移的三维有限元分析 被引量:1
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作者 唐倩 欧晓丽 +2 位作者 方志欣 龙智灵 罗海欧 《中国美容医学》 CAS 2024年第6期117-120,共4页
目的:利用全牙列精准扫描建模分析无托槽隐形矫治器扩展上颌牙弓时对后牙三维位移的影响。方法:选择2017年1月-2022年6月就诊于笔者医院口腔正畸科的86例成年患者为研究对象。所有患者均为安氏I类错牙合,矫治方案设计为仅通过邻面去釉... 目的:利用全牙列精准扫描建模分析无托槽隐形矫治器扩展上颌牙弓时对后牙三维位移的影响。方法:选择2017年1月-2022年6月就诊于笔者医院口腔正畸科的86例成年患者为研究对象。所有患者均为安氏I类错牙合,矫治方案设计为仅通过邻面去釉的方式排齐上下前牙,在全牙列精准扫描建模的基础上,构建无托槽隐形矫治器进行上颌牙弓扩弓前以及扩弓后的后牙三维方向有限元模型的对比。结果:第5组位移量的最大值(3.315 17)与最小值(3.139 25)的比值均为所有组别中最小的。与其他组相比,第5组位移最小值与根尖的距离更近;第5组的第二前磨牙对应得到的等效应力值最小,应力的分布更为均匀。结论:施加附件作用时,对前磨牙的控根效果显著优于磨牙,其中优化后扩弓支持附件对后牙的控根效果更为优秀。 展开更多
关键词 三维有限元 无托槽隐形矫治器 附件 扩弓
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出踩与面宽方向柱头科斗栱抗震性能对比试验及数值分析 被引量:2
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作者 薛建阳 宋德军 +1 位作者 吴晨伟 张栋 《土木工程学报》 EI CSCD 北大核心 2024年第2期11-24,共14页
为研究加载方向对斗栱抗震性能的影响,文章基于地震作用的随机性和斗栱出踩与面宽方向的构造差异,对2个足尺柱头科斗栱分别沿出踩和面宽方向进行拟静力试验,得到斗栱的破坏模式、承载力、刚度与强度退化、耗能和变形能力。结果表明:斗... 为研究加载方向对斗栱抗震性能的影响,文章基于地震作用的随机性和斗栱出踩与面宽方向的构造差异,对2个足尺柱头科斗栱分别沿出踩和面宽方向进行拟静力试验,得到斗栱的破坏模式、承载力、刚度与强度退化、耗能和变形能力。结果表明:斗栱在出踩和面宽方向分别加载时,大斗均相对平板枋滑移,馒头榫挤压剪断。出踩方向受力时单昂与桃尖梁相对滑移,面宽方向受力时整体明显转动。相比面宽方向受力的斗栱,出踩方向受力的斗栱具有更高的承载力、初始刚度和耗能能力,而变形能力较差。文章开展柱头科斗栱的数值分析,模拟结果与试验结果吻合较好,研究出踩和面宽不同加载方向、轴压荷载、木构件之间摩擦系数和木材弹性模量对其抗震性能的影响。结果表明:面宽方向是柱头科斗栱的最不利受力方向,其正负向承载力比出踩方向分别低19.21%和17.03%;轴压荷载和木构件之间摩擦系数越大,斗栱承载力越大,而木材顺纹弹性模量和横纹径向弹性模量对斗栱的初始刚度和承载力影响较小。 展开更多
关键词 古建筑木结构 柱头科斗栱 水平加载方向 抗震性能 数值分析
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严寒地区光伏支架受力分析及优化
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作者 马令勇 田航臣 +4 位作者 韩杨 姜伟 刘功良 齐晗兵 李栋 《节能技术》 CAS 2024年第3期237-243,共7页
光伏支架作为光伏系统的重要组成部分,结构设计至关重要。为提升严寒地区光伏支架的安全性和经济性,采用有限元模拟方法对大庆市典型光伏工程进行了参数化分析和优化设计,主要探究檩条间距、立柱数量和前后立柱间距等不同结构参数对支... 光伏支架作为光伏系统的重要组成部分,结构设计至关重要。为提升严寒地区光伏支架的安全性和经济性,采用有限元模拟方法对大庆市典型光伏工程进行了参数化分析和优化设计,主要探究檩条间距、立柱数量和前后立柱间距等不同结构参数对支架受力性能的影响。结果表明,支架挠度与檩条间距和立柱数量呈负相关,与前后立柱间距呈先增大后减小的趋势,临界荷载变化趋势与支架挠度变化趋势正好相反。并得出最佳优化方案:采用单块光伏板长度20%的檩条间距、斜梁水平投影60%的立柱间距、中间斜梁增加斜支撑和截面厚度2 mm的支架优化设计,此优化方案可使支架挠度降低71%。 展开更多
关键词 光伏支架 受力 有限元分析 挠度 优化
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汽车变速器支架冲压成形工艺参数优化 被引量:1
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作者 赵博宁 黄科拓 《科技创新与应用》 2024年第14期62-65,共4页
该文以汽车变速器支架为研究对象,利用Dynaform软件研究其冲压成形过程出现的常见缺陷和问题。首先采用单因素分析确定正交试验的参数范围,然后通过正交试验和极差分析,获得各参数对最大减薄率的影响主次顺序,即冲压速度大于摩擦系数大... 该文以汽车变速器支架为研究对象,利用Dynaform软件研究其冲压成形过程出现的常见缺陷和问题。首先采用单因素分析确定正交试验的参数范围,然后通过正交试验和极差分析,获得各参数对最大减薄率的影响主次顺序,即冲压速度大于摩擦系数大于模具间隙;对于最大增厚率,冲压速度大于模具间隙大于摩擦系数,相对最优工艺参数组合为摩擦系数0.100、模具间隙1.44 mm、冲压速度1000 mm/s。最大减薄率的数值为15.345%、最大增厚率的仿真数值为16.017%,优化后的零件成形质量良好,可降低破裂的风险。 展开更多
关键词 冲压成形 DYNAFORM 汽车变速器支架 正交试验 极差分析
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移动式多点出料装置设计与试验 被引量:1
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作者 陈武东 《农机化研究》 北大核心 2024年第3期76-80,86,共6页
目前,筒仓仓群的进料传统工艺路线是在每个仓顶上布置有一台带式输送机,通过搭接方式由一台传递给另一台,实现物料的连续输送。其在每台带式输送机的出料口处设置有三通,一通流向料仓仓顶的进料点,一通流向下台带式输送机,导致工艺配置... 目前,筒仓仓群的进料传统工艺路线是在每个仓顶上布置有一台带式输送机,通过搭接方式由一台传递给另一台,实现物料的连续输送。其在每台带式输送机的出料口处设置有三通,一通流向料仓仓顶的进料点,一通流向下台带式输送机,导致工艺配置复杂、设备布置繁琐,操作起来不方便,故障率也会增高。为此,设计了一种移动式多点出料装置,包括:机架布置在输送机托架上方,托架上固定有滑轨;滚轮、驱动机安装在机架上且二者传动连接;导向托架与机架固定,其上安装有出料辊和托辊组,出料辊与托辊组共同对输送带进行滚动支撑,导向托架的一端固定有出料斗,其出料端布置在输送机托架一侧。上述设置保证了带式输送机出料位置可调,当需要对依次排列的多个料仓进行输送进料时,只需要布置一台带式输送机即可。样机调试运行及对生产试验结果表明:装置设计的各项技术指标均符合国家标准的规定和设计规范要求,能够满足市场需求和生产需要,解决了料仓仓顶多点进料的工艺难点。 展开更多
关键词 多点出料装置 移动式 导向托架 出料辊 托辊组
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汽车线束支架选材研究
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作者 肖晶 吴文安 +1 位作者 卓靖 何伟 《上海塑料》 CAS 2024年第2期39-46,共8页
汽车线束防护在线束设计中起着重要作用,其中线束支架具有保护线束和固定线束的功能。传统的线束支架通常采用尼龙66(PA66)材料,然而随着尼龙价格的不断攀升,替代PA66的方案逐渐被提出。主要结合结构与材料性能,研究聚丙烯类材料替代尼... 汽车线束防护在线束设计中起着重要作用,其中线束支架具有保护线束和固定线束的功能。传统的线束支架通常采用尼龙66(PA66)材料,然而随着尼龙价格的不断攀升,替代PA66的方案逐渐被提出。主要结合结构与材料性能,研究聚丙烯类材料替代尼龙材料做线束支架的可能性。结果表明:汽车线束支架本体部分可使用20%滑石粉填充聚丙烯材料(PP-TD20)代替PA66,汽车底盘用线束支架可以采用30%玻纤增强聚丙烯材料(PP-GF30)。 展开更多
关键词 汽车线束 支架 聚丙烯 尼龙66
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斜拉桥长大节段组合式主梁悬臂施工技术研究
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作者 邱攀 黄辉 涂满明 《施工技术(中英文)》 CAS 2024年第12期118-124,共7页
鲁巴跨海大桥主航道桥为双塔双索面混凝土斜拉桥,大桥主梁为π形混凝土组合式主梁,标准节段长10.2m、宽17.3m、中心高2.5m;主梁斜拉索锚固块及横向横梁为预制装配式构件,边主梁及桥面板为现浇混凝土构件,各主要构件通过横向预应力连为... 鲁巴跨海大桥主航道桥为双塔双索面混凝土斜拉桥,大桥主梁为π形混凝土组合式主梁,标准节段长10.2m、宽17.3m、中心高2.5m;主梁斜拉索锚固块及横向横梁为预制装配式构件,边主梁及桥面板为现浇混凝土构件,各主要构件通过横向预应力连为一体。以该桥主梁悬臂施工为工程背景,从质量控制、施工计划、施工成本3个方面对主梁2种施工方案进行对比,最终确定适合本桥主梁施工的挂篮方案,可有效降低临时结构自重对已浇筑节段混凝土产生的附加应力影响,降低工程造价;同时,通过对2~15号主梁节段采用新型桁架式牵索挂篮施工进行专项设计,解决了主梁节段长、自重大、预制装配式构件安装精度要求高、节段施工周期长的难题。 展开更多
关键词 桥梁工程 斜拉桥 预制装配式 组合梁 悬吊支架 施工技术
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无褶皱吻合技术治疗结直肠恶性梗阻的应用价值
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作者 王娟 武广海 +2 位作者 张帅 李超 徐靖 《腹腔镜外科杂志》 2024年第1期48-51,共4页
目的:探讨结直肠吻合新技术无褶皱吻合术治疗结直肠恶性梗阻的应用价值。方法:收集2020年1月至2022年12月收治的54例左半结肠直肠癌合并结直肠梗阻患者的临床资料。患者均为急诊就诊,确诊结直肠梗阻且腹部CT测量扩张肠管直径>30 mm... 目的:探讨结直肠吻合新技术无褶皱吻合术治疗结直肠恶性梗阻的应用价值。方法:收集2020年1月至2022年12月收治的54例左半结肠直肠癌合并结直肠梗阻患者的临床资料。患者均为急诊就诊,确诊结直肠梗阻且腹部CT测量扩张肠管直径>30 mm。急症行内镜下经肛肠道自膨式金属支架置入术,术中取活检,病理结果证实恶性肿瘤。限期行腹腔镜结直肠癌切除术,术中应用无褶皱吻合技术进行一期吻合。术后随访7~24个月,评估吻合口相关并发症情况。结果:54例均完成腹腔镜结直肠癌切除术。术中测量近端肠管直径29.50~45.80 mm,平均(36.29±4.51)mm;远端肠管直径19.50~32.60 mm,平均(24.93±4.19)mm。近远端肠管管径不一致,行无褶皱吻合术,吻合放置抵钉座时间3~5 min,平均(3.80±0.79)min。术后无吻合口出血、狭窄、漏等并发症发生,术后随访未发生局部复发等远期并发症。结论:无褶皱吻合技术应用于结直肠恶性梗阻支架置入术后吻合确切,手术安全、可靠。 展开更多
关键词 结直肠肿瘤 肠梗阻 腹腔镜检查 无褶皱吻合 自膨式金属支架
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无托槽隐形矫治器治疗骨性Ⅱ类错[牙合]的疗效分析
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作者 王茜 王伟砚 李光辉 《成都医学院学报》 CAS 2024年第3期442-445,共4页
目的 探讨无托槽隐形矫治器治疗骨性Ⅱ类错[牙合]的疗效。方法 以2021年7月至2023年10月在郑州大学第一附属医院进行正畸治疗的87例骨性Ⅱ类错[牙合]患者为研究对象开展回顾性分析,根据应用矫治器的不同分为传统组(应用传统固定矫治器治... 目的 探讨无托槽隐形矫治器治疗骨性Ⅱ类错[牙合]的疗效。方法 以2021年7月至2023年10月在郑州大学第一附属医院进行正畸治疗的87例骨性Ⅱ类错[牙合]患者为研究对象开展回顾性分析,根据应用矫治器的不同分为传统组(应用传统固定矫治器治疗,n=44)和隐形组(应用无托槽隐形矫治器治疗,n=43)。比较两组矫治效果[采用美国正畸专家认证委员会(ABO)评级系统评定]、侧貌美学指标、牙周指数[探诊深度(PD)、菌斑指数(PLI)及牙龈指数(GI)]及龈沟液炎症因子[白细胞介素-1β(IL-1β)和可溶性细胞间黏附分子1(sICAM-1)]水平。结果 矫治后,隐形组ABO评级系统中的8项分值及总分与传统组比较,差异无统计学意义(P>0.05);矫治后,两组颌凸角、上下中切牙角、U1-PP、FMA、UL-EP、TLL-EP均优于矫治前(P<0.05),其中隐形组上下中切牙角、FMA优于传统组(P<0.05);矫治后,隐形组PD、PLI、GI及龈沟液IL-1β、sICAM-1水平均低于传统组(P<0.05)。结论 无托槽隐形矫治器可有效矫正骨性Ⅱ类错[牙合]畸形,提高患者侧貌美观度,并能减少对牙周组织的损害。 展开更多
关键词 无托槽隐形矫治器 骨性Ⅱ类错[牙合] 咬合功能 侧貌美观度
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不锈钢支架熔模铸造工艺优化
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作者 张晓光 仓欣蕾 彭彬 《铸造》 CAS 2024年第2期257-261,共5页
通过ProCAST软件对除草机不锈钢支架进行熔模铸造的数值模拟,预测铸件缩孔缺陷分布情况,并对其浇注系统进行改善。利用正交试验对铸件的工艺参数进行研究,通过分析获得工艺参数的最佳方案。对该结果进行数值仿真以及实际铸造,发现铸件... 通过ProCAST软件对除草机不锈钢支架进行熔模铸造的数值模拟,预测铸件缩孔缺陷分布情况,并对其浇注系统进行改善。利用正交试验对铸件的工艺参数进行研究,通过分析获得工艺参数的最佳方案。对该结果进行数值仿真以及实际铸造,发现铸件缺陷明显减少,这为不锈钢支架的生产提供了参考。 展开更多
关键词 熔模铸造 PROCAST 不锈钢支架 正交试验
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高压线束支架多工位连续模设计
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作者 王富春 蒙以嫦 +1 位作者 关来德 苏治德 《科技创新与应用》 2024年第20期127-129,133,共4页
该文分析高压线束支架的冲压成形工艺及排样方法,阐述该连续冲裁模的结构及工作零件的加工方法,凹模采用镶拼结构,节约模具钢,零件加工难度降低,制造成本降低。实践证明,该模具结构合理,冲件质量稳定,较好地满足冲件精度和批量生产的要求。
关键词 冲压工艺 排样 连续模 直通式 高压线束支架
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