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Aero-propulsion analysis of distributed ducted-fan propulsion based on lifting-line driven body-force model
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作者 Hanru LIU Xingyu ZHAO +2 位作者 Fang ZHOU Yuyao FENG Yangang WANG 《Chinese Journal of Aeronautics》 2025年第2期60-74,共15页
As the environmental problems become increasingly serious,distributed electrical propulsion systems with higher aerodynamic efficiency and lower pollution emission have received extensive attention in recent years.The... As the environmental problems become increasingly serious,distributed electrical propulsion systems with higher aerodynamic efficiency and lower pollution emission have received extensive attention in recent years.The distributed electrical propulsion usually employs the new aero-propulsion integrated configuration.A simulation strategy for internal and external flow coupling based on the combination of lifting line theory and body force method is proposed.The lifting line theory and body force method as source term are embedded into the Navier-Stokes formulation.The lift and drag characteristics of the aero-propulsion coupling configuration are simulated.The results indicate that the coupling configuration has the most obvious lift augmentation at 12°angle of attack,which can provide an 11.11%increase in lift for the airfoil.At 0°angle of attack,the pressure difference on the lip parts provides the thrust component,which results in a lower drag coefficient.Additionally,the failure impact of a ducted fan at the middle or edge on aerodynamics is investigated.For the two failure conditions,the lift of the coupling configuration is decreased significantly by 27.85%and 26.14%respectively,and the lip thrust is decreased by 70.74%and 56.48%respectively. 展开更多
关键词 Ducted fan Distributed electrical PROPULSION lifting line theory Body force method Aero-propulsion integrated CONFIGURATION
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Biomimetic inner helicoidal microfluidics with enhanced capillary rise for step liquid lifting mimicking transpiration
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作者 Zhaolong Wang Yinfeng Li +5 位作者 Ziheng Zhan Mingzhu Xie Yingying Li Chengqi Zhang Zhichao Dong Yong Shuai 《International Journal of Extreme Manufacturing》 2025年第2期737-747,共11页
Bionic microfluidics is garnering increasing attention due to the superior fluidic performance enabled by biomimetic microstructures.Inspired by the unique structures of young pumpkin stems,we fabricate helicoidally p... Bionic microfluidics is garnering increasing attention due to the superior fluidic performance enabled by biomimetic microstructures.Inspired by the unique structures of young pumpkin stems,we fabricate helicoidally patterned microchannels with precisely controlled morphologies using the projection micro-stereolithography(PμSL)-based 3D printing technique.Our helicoidally patterned microchannels achieve approximately twice the liquid lifting height compared to similarly sized smooth microchannels.This improvement is attributed to the enhanced capillary force.The additional meniscus formed between the helicoidally patterned microstructures significantly contributes to the increased capillary effects.Furthermore,the underlying mechanisms of fluidic performance in helicoidally patterned microchannels are theorized using a newly developed equation,which is also employed to optimize the geometric parameters and fluidic performance of the biomimetic helicoidal microchannels.Additionally,our biomimetic helicoidally patterned microchannels facilitate a significant step-lifting phenomenon,mimicking tall trees'transpiration.The fluidic performance of our biomimetic helicoidally patterned microchannels show promise for applications in enhanced liquid lifting,step-lifting,clean-water production,and others. 展开更多
关键词 BIOMIMETIC helicoidally patterned microchannel enhanced capillary rise step lifting mimicked transpiration
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Two-point lifting/retracting technology for transumbilical single-port laparoscopic cholecystectomy based on the anatomical features of Calot's triangle
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作者 Li-Min Kang Ying-Hong Zhao +2 位作者 Fa-Kun Yu Fu-Wei Zhang Xin Kang 《World Journal of Gastrointestinal Surgery》 2025年第7期165-171,共7页
BACKGROUND Among the rapidly developing single-incision laparoscopic cholecystectomy(LC)techniques,transumbilical single-incision LC is increasingly replacing the traditional LC,with advantages of minimal invasion,sli... BACKGROUND Among the rapidly developing single-incision laparoscopic cholecystectomy(LC)techniques,transumbilical single-incision LC is increasingly replacing the traditional LC,with advantages of minimal invasion,slight postoperative pain,faster recovery.Despite the advantages mentioned above,the currently available specialized single-port laparoscopic instruments are hindered by high costs and limited applications,challenging their widespread use in medical facilities.AIM To design a two-point lifting/retracting(TPLR)technique for transumbilical single-port LC(TUSPLC)based on the anatomical features of the Calot's triangle(or cystohepatic triangle)and investigate its surgical feasibility.METHODS The clinical data of 103 patients who underwent TUSPLC utilizing the TPLR technique in the Department of Hepatobiliary Surgery at our hospital between June 2023 and June 2024 were retrospectively analyzed.The patient cohort included 82 cases of cholelithiasis,11 cases of gallbladder polyps,6 cases of concurrent gallstones and polyps,and 4 cases of gallbladder adenomyomatosis.RESULTS All the surgical procedures were conducted using standard laparoscopic instruments.Surgery was successful in 98(95.14%)patients using the TPLR method,which effectively exposed the Calot's triangle during surgery.The operative time ranged from 35 to 70 minutes,with an average of 42.4±26.8 minutes.In 3 cases,an additional operative port was required below the xiphoid process,and 2 cases were converted to conventional three-port LC.No complications such as abdominal pain,fever,bile leakage,hemorrhage,or incisional infection were noted postoperatively.No discernible surgical scars were observed at the 2-week postoperative reexamination.Additionally,a 3-month follow-up period revealed no complications.CONCLUSION The TPLR technique,developed based on the anatomical features of the Calot's triangle,facilitates exposure of the Calot's triangle during surgery.It is a simple,safe,feasible,and cost-effective method,and a promising approach for single-port LC. 展开更多
关键词 Calot's triangle Two-point lifting/retracting technique Transumbilical single-port surgery LAPAROSCOPY CHOLECYSTECTOMY
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A lifting-wavelet-based iterative thresholding correction for atomic force microscopy images with vertical distortion
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作者 Yifan Bai Yinan Wu Yongchun Fang 《Nanotechnology and Precision Engineering》 2025年第3期29-40,共12页
To eliminate distortion caused by vertical drift and illusory slopes in atomic force microscopy(AFM)imaging,a lifting-wavelet-based iterative thresholding correction method is proposed in this paper.This method achiev... To eliminate distortion caused by vertical drift and illusory slopes in atomic force microscopy(AFM)imaging,a lifting-wavelet-based iterative thresholding correction method is proposed in this paper.This method achieves high-quality AFM imaging via line-by-line corrections for each distorted profile along the fast axis.The key to this line-by-line correction is to accurately simulate the profile distortion of each scanning row.Therefore,a data preprocessing approach is first developed to roughly filter out most of the height data that impairs the accuracy of distortion modeling.This process is implemented through an internal double-screening mechanism.A line-fitting method is adopted to preliminarily screen out the obvious specimens.Lifting wavelet analysis is then carried out to identify the base parts that are mistakenly filtered out as specimens so as to preserve most of the base profiles and provide a good basis for further distortion modeling.Next,an iterative thresholding algorithm is developed to precisely simulate the profile distortion.By utilizing the roughly screened base profile,the optimal threshold,which is used to screen out the pure bases suitable for distortion modeling,is determined through iteration with a specified error rule.On this basis,the profile distortion is accurately modeled through line fitting on the finely screened base data,and the correction is implemented by subtracting the modeling result from the distorted profile.Finally,the effectiveness of the proposed method is verified through experiments and applications. 展开更多
关键词 Atomic force microscopy lifting wavelet analysis Iterative thresholding algorithm Vertical distortion
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A comparative study on kinetics and dynamics of two dump truck lifting mechanisms using MATLAB simscape
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作者 Thong Duc Hong Minh Quang Pham +2 位作者 Son Cong Tran Lam Quang Tran Truong Thanh Nguyen 《Theoretical & Applied Mechanics Letters》 CAS CSCD 2024年第2期146-156,共11页
In this paper,two lifting mechanism models with opposing placements,which use the same hydraulic hoist model and have the same angle of 50°,have been developed.The mechanical and hydraulic simulation models are e... In this paper,two lifting mechanism models with opposing placements,which use the same hydraulic hoist model and have the same angle of 50°,have been developed.The mechanical and hydraulic simulation models are established using MATLAB Simscape to analyze their kinetics and dynamics in the lifting and holding stages.The simulation findings are compared to the analytical calculation results in the steady state,and both methods show good agreement.In the early lifting stage,Model 1 produces greater force and discharges goods in the container faster than Model 2.Meanwhile,Model 2 reaches a higher force and ejects goods from the container cleaner than its counterpart at the end lifting stage.The established simulation models can consider the effects of dynamic loads due to inertial moments and forces generated during the system operation.It is crucial in studying,designing,and optimizing the structure of hydraulic-mechanical systems. 展开更多
关键词 Dump truck lifting mechanism HYDRAULIC MATLAB Simscape Kinetic dynamic analysis
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Trajectory compensation for multi-robot coordinated lifting system considering elastic catenary of the rope
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作者 ZHAO Xiangtang ZHAO Zhigang +2 位作者 SU Cheng MENG Jiadong WANG Baoxi 《High Technology Letters》 EI CAS 2024年第3期252-262,共11页
The multi-robot coordinated lifting system is an unconstrained system with a rigid and flexible coupling.The deformation of the flexible rope causes errors in the movement trajectory of the lifting system.Based on the... The multi-robot coordinated lifting system is an unconstrained system with a rigid and flexible coupling.The deformation of the flexible rope causes errors in the movement trajectory of the lifting system.Based on the kinematic and dynamic analysis of the lifting system,the elastic catenary mod-el considering the elasticity and mass of the flexible rope is established,and the effect of the deform-ation of the flexible rope on the position and posture of the suspended object is analyzed.According to the deformation of flexible rope,a real-time trajectory compensation method is proposed based on the compensation principle of position and posture.Under the lifting task of the low-speed move-ment,this is compared with that of the system which neglects the deformation of the flexible rope.The trajectoy of the lifting system considering the deformation of flexible rope.The results show that the mass and elasticity of the flexible rope can not be neglected.Meanwhile,the proposed trajectory compensation method can improve the movement accuracy of the lifting system,which verifies the ef-fectiveness of this compensation method.The research results provide the basis for trajectory plan-ning and coordinated control of the lifting system。 展开更多
关键词 multi-robot lifting system deformation of flexible rope elastic catenary model compensation principle of position and posture trajectory compensation
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Research on the Lifting Path of Data Literacy Ability of Applied University Teachers under the Perspective of Organizational Learning
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作者 Shuli Gao Yanli Guo 《Open Journal of Applied Sciences》 2024年第2期320-329,共10页
With the arrival of the big data era, the modern higher education model has undergone radical changes, and higher requirements have been put forward for the data literacy of college teachers. The paper first analyzes ... With the arrival of the big data era, the modern higher education model has undergone radical changes, and higher requirements have been put forward for the data literacy of college teachers. The paper first analyzes the connotation of teacher data literacy, and then combs through the status quo and dilemmas of teachers’ data literacy ability in applied universities. The paper proposes to enhance the data literacy ability of teachers from the perspective of organizational learning. Through building a digital culture, building a data-driven teaching environment, and constructing an interdisciplinary learning community to further promote the application of the theory and practice of datafication inside and outside the organization, and ultimately improve the quality of teaching. 展开更多
关键词 Organizational Learning Teachers’ Data Literacy lifting Paths
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一种生成双正交紧支复小波的Lifting方法 被引量:18
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作者 陈祥训 淡文刚 《中国电机工程学报》 EI CSCD 北大核心 2001年第5期34-37,42,共5页
提出了一种构造双正交紧支复小波的方法 :以现有任何一种正交或双正交实小波为基础 ,可构造出消失矩阶数可任意选定的无穷多个相频特性 (包括线性相位特性 )不同的双正交紧支复小波。其特点为 :由于是双正交紧支型 ,可采用Mallat算法等... 提出了一种构造双正交紧支复小波的方法 :以现有任何一种正交或双正交实小波为基础 ,可构造出消失矩阶数可任意选定的无穷多个相频特性 (包括线性相位特性 )不同的双正交紧支复小波。其特点为 :由于是双正交紧支型 ,可采用Mallat算法等快速算法 ,因此使用时实时性好 ;因为是复小波 ,所以能提取电力系统至关重要的相位信息 ;具有多种相频特性 ,便于与相频特性多变的电力系统信号匹配等 ,因此这类小波在电力系统有广泛的应用前景。 展开更多
关键词 电力系统 小波分析 lifting方法 双正交紧支复小波
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Construction analysis on integral lifting of steel structure by the vector form intrinsic finite element 被引量:3
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作者 朱明亮 陈雪琪 郭正兴 《Journal of Southeast University(English Edition)》 EI CAS 2016年第4期451-456,共6页
A newnumerical method based on vector form intrinsic finite element(VFIFE) is proposed to simulate the integral lifting process of steel structures. First, in order to verify the validity of the VFIFE method, taking... A newnumerical method based on vector form intrinsic finite element(VFIFE) is proposed to simulate the integral lifting process of steel structures. First, in order to verify the validity of the VFIFE method, taking the steel gallery between the integrated building and the attached building of Nanjing M obile Communication Buildings for example, the static analysis was carried out and the corresponding results were compared with the results achieved by the traditional finite element method. Then, according to the characteristics of dynamic construction of steel structure integral lifting, the tension cable element was employed to simulate the behavior of dynamic construction. The VFIFE method avoids the iterative solution of the stiffness matrix and the singularity problems. Therefore, it is simple to simulate the complete process of steel structure lifting construction.Finally, by using the VFIFE, the displacement and internal force time history curves of the steel structures under different lifting speeds are obtained. The results show that the lifting speed has influence on the lifting force, the internal force, and the displacement of the structure. In the case of normal lifting speed, the dynamic magnification factor of 1. 5 is safe and reasonable for practical application. 展开更多
关键词 integral lifting vector form intrinsic finite element(VFIFE) steel gallery whole process of construction dynamic magnification factor
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Acupuncture of lifting and pressing manipulation for upper limb paralysis after stroke 被引量:1
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作者 丁邦友 段君毅 +1 位作者 周艳丽 曹晓雯 《World Journal of Acupuncture-Moxibustion》 CSCD 2016年第2期31-36,共6页
Objective To compare the difference of clinical efficacy between acupuncture of lifting and pressing manipulation and conventional acupuncture in motor function recovery of hemiplegic upper limb after stroke, so as to... Objective To compare the difference of clinical efficacy between acupuncture of lifting and pressing manipulation and conventional acupuncture in motor function recovery of hemiplegic upper limb after stroke, so as to provide referential support for clinical application. Method Fifty-nine patients with upper limb hemiplegia after stroke were selected and divided into group A (conventional acupuncture ± lifting and pressing manipulation, 30 cases} and group B (conventional acupuncture, 29 cases} according to random number table method. Upper limb motor function and activity of daily living of patients in the two groups were scored before and after treatment, and the results were analyzed and compared. Results The score of upper limb FugI-Meyer motor function of patients was 22.4 ± 2.83 and 32.97 ± 2.92 before and after treatment in group A, and was 19.89 ± 3.13 and 26.62 ± 3.31 before and after treatment in group B, and the difference between the two groups before and after treatment was significant (P〈0.01}. The score of Barthel index of patients was 60.67 ± 4.65 and 73.00 ± 3.82 before and after treatment in group A, and was 50.52 ± 5.15 and 60.17 ± 4.89 before and after treatment in group B, and the difference between the two groups before and after treatment was not statistcally significant {P〉0.05). Conclusion Lifting and pressing manipulation combined with conventional acupuncture can better improve upper limb motor function of upper limb paralysis of patients after stroke. 展开更多
关键词 limbs hemiplegia after stroke acupuncture manipulating efficacyevaluation lifting and pressing method
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Lifting Scheme及其在小波图象编码中的应用 被引量:2
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作者 曾剑芬 马争鸣 《中国图象图形学报(A辑)》 CSCD 北大核心 2001年第11期1111-1117,共7页
L ifting Schem e是构造第二代小波的关键技术 .相对于第一代小波而言 ,L ifting Scheme是一种比 Mallat算法更快、更简单和更容易操作的算法 ,也是 JPEG2 0 0 0推荐的算法 .为了将其应用到小波图象编码中 ,提出了一种对 L ifting Schem... L ifting Schem e是构造第二代小波的关键技术 .相对于第一代小波而言 ,L ifting Scheme是一种比 Mallat算法更快、更简单和更容易操作的算法 ,也是 JPEG2 0 0 0推荐的算法 .为了将其应用到小波图象编码中 ,提出了一种对 L ifting Scheme作适当改进以用于小波图象编码的方法 .该方法就是先用 L ifting Scheme来实现 D9/ 7双正交小波变换 ,然后再用这种技术实现的 D9/ 7双正交小波变换来进行图象压缩编码 .在将 L ifting Schem e算法用于小波图象编码的过程中 ,对该算法做了必要的简化 ,以便保证每个提升 (lifting)环节都是 FIR滤波 .同时 ,根据能量守恒的原则 ,重新调整了尺度因子 .实验结果表明 ,这种经过改进的 L ifting Schem e取得了比 展开更多
关键词 小波图象编码 MALLAT算法 lifting SCHEME 小波分析 图象压缩
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细分曲面切片轮廓线的Lifting小波变换 被引量:1
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作者 区士颀 宾鸿赞 《中国机械工程》 EI CAS CSCD 北大核心 2005年第17期1519-1523,共5页
基于Lifting小波变换原理对细分曲面实体切片操作产生的离散交点序列进行处理,将它们组织为属于多个层次结构的多分辨率曲线。用4种不同的Lifting小波变换进行了多分辨率曲线的构造实验,并对产生的多分辨率曲线进行了对比,讨论分析了这... 基于Lifting小波变换原理对细分曲面实体切片操作产生的离散交点序列进行处理,将它们组织为属于多个层次结构的多分辨率曲线。用4种不同的Lifting小波变换进行了多分辨率曲线的构造实验,并对产生的多分辨率曲线进行了对比,讨论分析了这些Lifting变换方法的性能特点。 展开更多
关键词 快速原型制造技术 细分曲面 切片 lifting小波变换
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用lifting方法设计最优LPPR-FIR滤波器组
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作者 陈佩 张卫东 +1 位作者 许晓鸣 徐润生 《电子与信息学报》 EI CSCD 北大核心 2002年第9期1202-1208,共7页
该文研究了如何用lifting方法构造线性相位完全重建有限脉冲响应(LPPR-FIR)滤波器组的优化设计问题,即如何转化为一个二次型优化问题.然后把该方法推广到M带FIR滤波器组,考虑在一种特殊情形中如何构造具有线性相位性质的M带PR-FIR滤波器... 该文研究了如何用lifting方法构造线性相位完全重建有限脉冲响应(LPPR-FIR)滤波器组的优化设计问题,即如何转化为一个二次型优化问题.然后把该方法推广到M带FIR滤波器组,考虑在一种特殊情形中如何构造具有线性相位性质的M带PR-FIR滤波器组,最后列举了几个例子说明如何用lifting方法构造M带LPPR-FIR滤波器组。 展开更多
关键词 LPPR-FIR滤波器组 lifting方法 M带滤波器组 完全重构 线性相位
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基于Lifting的小波变换通用硬件实现方法研究
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作者 王芳 朱珂 周晓方 《计算机工程与应用》 CSCD 北大核心 2006年第8期87-91,共5页
文章提出了一套完整的基于Lifting算法小波通用硬件实现的流程。该方法系统分析了目前基于Lifting算法小波实现过程中的有限精度分析,基本一维、两维小波变换结构设计以及常用优化算法,提炼出了一套小波设计的通用方法。该文将以6/10小... 文章提出了一套完整的基于Lifting算法小波通用硬件实现的流程。该方法系统分析了目前基于Lifting算法小波实现过程中的有限精度分析,基本一维、两维小波变换结构设计以及常用优化算法,提炼出了一套小波设计的通用方法。该文将以6/10小波变换为例介绍该方法的具体实现过程,为设计者提供了一整套设计一个高性能小波可遵循的流程,它可以应用于小波变换的硬件设计以及相关的基于小波变换的信号处理系统设计。 展开更多
关键词 基于lifting算法的小波变换 通用硬件实现 小波变换结构设计
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A NEW TWO-DIMENSIONAL SIGNAL DECOMPOSITION SCHEME USING THE EXTREME-LIFTING SCHEME
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作者 Liu Baofang Ping Xijian Deng Guanglin Shao Meizhen(Dept. of Info. Sci., University of Information Engineering, Zhengzhou 450002)(P.O.Box 1965, Beijing 100091) 《Journal of Electronics(China)》 2001年第2期105-112,共8页
This paper discusses the signal decomposition method using the extreme-lifting scheme and two two-dimensional decomposition schemes: separable one-dimensional scheme and two-dimensional scheme with quincunx sampling. ... This paper discusses the signal decomposition method using the extreme-lifting scheme and two two-dimensional decomposition schemes: separable one-dimensional scheme and two-dimensional scheme with quincunx sampling. The structure of the relation "~" between Ex and Ey of these two schemes is symmetrical and both these two schemes have shortcomings)An unsymmetrical scheme of the extreme-lifting scheme is proposed in this paper, which canbe directly used to decompose two-dimensional image and can get better decomposition result than the two schemes with little computation cost. 展开更多
关键词 SIGNAL DECOMPOSITION Min-lifting SCHEME Quincunx sampling lifting SCHEME
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Research on the special lifting devices for steel box girders of Sutong Bridge
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作者 Chen Ming Wu Qihe +1 位作者 Luo Chengbin Zhou Hanfa 《Engineering Sciences》 EI 2009年第1期63-68,F0003,共7页
Sutong Bridge is a cable-stayed bridge with a steel box girder and a main span of 1 088 m.The steel box girder of main span includes five portions:back span large unit,large block of pylon,standard girder,back span cl... Sutong Bridge is a cable-stayed bridge with a steel box girder and a main span of 1 088 m.The steel box girder of main span includes five portions:back span large unit,large block of pylon,standard girder,back span closure girder and middle span closure girder.Each back span large unit is fabricated by welding several deck segments together in factory,and is erected by floating crane.As navigational clearance of the main bridge is high,the traditional truss lifting device can't satisfy the requirement of domestic lifting cranes for this kind of lifting height and weight.Hence,a kind of lighter lifting device for the erection of back span large units was accepted for this bridge.In this paper,the design and use of this lifting device is introduced.The upper structure used lifting gantry to install the standard girder segment by cantilever method.Because the bridge's navigation clearance is high,and the girder segment is wide and heavy,the meteorology and hydrology condition of the bridge district is abominable,and the requirements of long cable girder side pull-in,structure and performance propose high request to the lifting gantry.In this paper,the design and use key point of long cable pull-in angle adjustment device integrate into lifting gantry is introduced. 展开更多
关键词 Sutong Bridge large units lifting devices cantilever installation lifting gantry design and use
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随机法和Hensel Lifting联合的浮点乘测试用例生成方法 被引量:1
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作者 冯春阳 杨靓 黄士坦 《计算机辅助设计与图形学学报》 EI CSCD 北大核心 2014年第9期1509-1521,共13页
针对浮点乘仿真验证时覆盖率不全面和边界角用例定位难的问题,提出一种随机法和Hensel lifting理论联合的浮点乘测试用例生成方法.首先通过分析测试用例生成域设计了一个浮点乘测试用例产生及功能仿真平台;然后利用Hensel lifting理论... 针对浮点乘仿真验证时覆盖率不全面和边界角用例定位难的问题,提出一种随机法和Hensel lifting理论联合的浮点乘测试用例生成方法.首先通过分析测试用例生成域设计了一个浮点乘测试用例产生及功能仿真平台;然后利用Hensel lifting理论提出一种统一的边界角浮点乘测试用例生成模型.将所提方法用于文中设计的功能仿真平台中,并将该平台与典型浮点测试工具集进行浮点乘性能比较的实验结果表明,该方法可使浮点乘检错率随浮点数位宽的增加而提升,最高增幅可达9.77%,比随机法检错率平均提高15.98%,比典型浮点测试工具集检错率平均提高1.9%. 展开更多
关键词 浮点乘 仿真验证 边界角用例 Hensel lifting 随机法 检错率
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离散小波变换的最优Lifting分解方法 被引量:1
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作者 吴江华 张田文 《电子学报》 EI CAS CSCD 北大核心 2004年第11期1910-1914,共5页
现有Lifting分解 (LiftingFactorization ,LF)算法不能在较短时间内求解出较长离散小波变换 (DiscreteWaveletTransform ,DWT)滤波器组的所有数值稳定LF ,更无法计算最优LF .在LF的形式化分析基础上 ,提出了DWT多相矩阵的常数最大公因... 现有Lifting分解 (LiftingFactorization ,LF)算法不能在较短时间内求解出较长离散小波变换 (DiscreteWaveletTransform ,DWT)滤波器组的所有数值稳定LF ,更无法计算最优LF .在LF的形式化分析基础上 ,提出了DWT多相矩阵的常数最大公因子分解方法 ,极大缩小了分解搜索空间 ;进一步 ,从数值稳定性及计算复杂性两方面研究了LF评价问题 ;最后 ,提出了基于联合优化的最优LF算法 .实验结果表明 ,本文算法在解的质量。 展开更多
关键词 DWT 最优lifting分解 Euclidean算法 分解稳定性
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Analysis of Hydraulic Lifting Device for Wind Power Tower Loading and Unloading Vehicle
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作者 HUANG Longheng LEI Yi YANG Xueliang 《外文科技期刊数据库(文摘版)工程技术》 2021年第12期1109-1112,共6页
In the construction of wind power tower, the loading and unloading operation of tower is basically involved. However, due to the large size of wind power tower and its great characteristics in weight, it is necessary ... In the construction of wind power tower, the loading and unloading operation of tower is basically involved. However, due to the large size of wind power tower and its great characteristics in weight, it is necessary to use two gantry cranes to handle the tower crane at the same time, so as to effectively meet the transportation and handling of loading and unloading vehicles. However, in the actual construction, it is often affected by the heavy operation of the equipment. Therefore, based on this situation, this paper studies the hydraulic lifting device for wind power tower loading and unloading vehicle, in order to ensure that the device can play its due role in operation. 展开更多
关键词 wind power tower loading and unloading vehicles hydraulic lifting device CRANE lifting rod
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Lifting模的直和 被引量:2
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作者 吴德军 《甘肃科学学报》 2003年第3期19-20,共2页
证明了在一定条件下,两个lifting模的直和是lifting模。
关键词 lifting 小M-投射模 伪M-投射模
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