Journal articles: 'Crossbeam'

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Love, Milton S., Mary M. Nishimoto, Scott Clark, Li Kui, Azivy Aziz, and David Palandro. "A comparison of two remotely operated vehicle (ROV) survey methods used to estimate fish assemblages and densities around a California oil platform." PLOS ONE 15, no. 11 (November 10, 2020): e0242017. http://dx.doi.org/10.1371/journal.pone.0242017.

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Offshore oil and gas platforms have a finite life of production operations. Once production ceases, decommissioning options for the platform are assessed. The role that a platform’s jacket plays as fish habitat can inform the decommissioning decision. In this study, conducted along the crossbeams of a California platform jacket and using an ROV, we compared estimates of fish diversity and densities determined from a targeted “biological” survey with those from a replicated “structural” survey. We found that the water column fish species assemblages characterized by the two methods were similar. By contrast, the two survey methods yielded different species assemblages inhabiting the crossbeam at the platform jacket base. This difference occurred because, at least off California, the platform jacket base species diversity tends to be highest where the bottom crossbeam is undercut, creating sheltering sites for many species. Because the structural method inadequately imaged the seafloor-crossbeam interface, particularly where a gap occurred between crossbeam and seafloor, substantial numbers of fishes were not visible. While we cannot extrapolate from this study to all platforms’ worldwide, it is clear that routine platform structural integrity surveys may be a valuable source for opportunistic marine community surveys. Intentional planning of the structural survey to incorporate relatively minor variations (e.g., maintaining fixed ROV distance from the infrastructure and consistent 90° camera angle) coupled with a deliberate consideration of the platform ecology (e.g., positioning the ROV to capture the seafloor-crossbeam interface) can substantially improve the effects on fish assemblage assessments from routine structural surveys without compromising the integrity assessment. We suggest that these biases should be both acknowledged and, understood when using routine structural surveys to inform platform ecology assessment. Additional consideration may be given to structural surveys that incorporate incremental adjustments to provide better data applicability to biological assessments.

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Guo, Tie Neng, Dong Liang Guo, Li Gang Cai, Bin Song, and Jing Nan Zhao. "Influence of Bolted Joint on Dynamic Characteristics of Combined Three-Section Crossbeam." Applied Mechanics and Materials 37-38 (November 2010): 534–39. http://dx.doi.org/10.4028/www.scientific.net/amm.37-38.534.

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The combined three-section crossbeam is an important component in the heavy gantry CNC milling-lathing machine tool and the dynamic characteristics are key precision factors for the machine tool. Three sections of the combined crossbeam are bolted by large industrial bolts and the influence of bolted joints should be evaluated in the dynamic analysis of the combined crossbeam. The dynamic characteristics of the combined three-section crossbeam were extracted by the modal experiment. The FEM of the monolithic crossbeam was modeled to analyze the dynamic characteristic parameters. The comparison of the analysis result and experimental result were shown. The experimental result matched well with the FEM of the monolithic crossbeam without bolted joints. As a result, the influence of the bolted joints could be ignorable in dynamic characteristic for the combined three-section crossbeam.

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Deng, Xiao Lei, Wei Min Yang, and Jian Chen Wang. "Statics Analysis for the Crossbeam of Large Gantry CNC Machine under Six Working Conditions." Advanced Materials Research 605-607 (December 2012): 1523–26. http://dx.doi.org/10.4028/www.scientific.net/amr.605-607.1523.

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The crossbeam is one of the main supporting parts of large gantry CNC machines. The deformation of the crossbeam under loads at work has great impact on integrated machining errors of machines. However, the crossbeam assembly’s structure and the corresponding loads are so complex that it’s difficult to get them through experiences and analytic methods. In this paper, the FE statics analysis method is used to simulate and analysis of the crossbeam under six main working conditions, obtaining deformation and stress distribution of the crossbeam under each conditions. The results show that when the slippery saddle is at the middle of the crossbeam and the ram extends to 100% length (the distance between the end of ram and the bottom of slippery saddle is 1.29 m), the total deformation of the crossbeam assembly is 6.4914 × 10-5m, the maximum deformation is up to 3.4872 × 10-5m, and the maximum stress is 1.1882 × 107Pa appearing at the hole of the drive shaft. The design of the crossbeam can meet the work requirements well. And analysis results present a basis for further optimization analysis and structural improvements of the crossbeam.

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Cao, Guo Hui, Zhen Yu Xie, Ming Cai Wen, and Ran He. "Deflection Test on CFST Arch Bridge with CFRP Slings." Advanced Materials Research 295-297 (July 2011): 1079–87. http://dx.doi.org/10.4028/www.scientific.net/amr.295-297.1079.

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The ultimate bearing capacity test is carried on CFST arch bridge model with CFRP slings, and the deflection of tie-beams, CFST arch, crossbeams, decks is also tested. Studies have shown that before the sliping of 4# CFRP sling, the deflection growth of east and west tie-beam, east and west arch both has good symmetry. The deflection growth of crossbeams and decks also has good symmetry, but after the sliping of 4# CFRP sling(located at the middle of west tie-beam), the structural internal forces redistribution appeared. The deflection of west tie-beam increased suddenly, and the mid-span deflection of west tie-beam is larger than that of east tie-beam by 14.6%. The mid-span deflection of east arch is larger than that of west arch by 9.9%. The deflection of crossbeam at 3L/8 and L/4 sections are respectively larger than those of crossbeam at 5L/8 and 3L/4 sections by 13.8% and 5.3%, The deflection of 3#, 2# and 1# decks are respectively larger than those of 4#, 5# and 6# decks by 7.8%, 13.2% and 17.1%. After the snapping of 10# CFRP sling(located at 3L/8 section of east tie-beam), the structural internal forces would appear redistribution. The deflection of east tie-beam would increase suddenly. The mid-span deflection of east tie-beam is larger than that of west tie-beam by 31.7%, and the mid-span deflection of east arch is larger than that of west arch by 21.3%. The deflection of crossbeam at 3L/8 and L/4 sections are respectively larger than those of 5L/8 and 3L/4 sections by 24.7% and 22.5%. The deflection of 3#, 2# and 1# decks are respectively larger than those of 4#, 5# and 6# decks by 16.2%, 24.5% and 28.6%.

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Huang, Qing, Wei Fang Chen, Wen Hua Ye, Pei Huang Lou, and Shi Hao Liu. "Optimization Design for the Large Gantry Machining Center Crossbeam." Applied Mechanics and Materials 130-134 (October 2011): 2284–87. http://dx.doi.org/10.4028/www.scientific.net/amm.130-134.2284.

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The crossbeam is an important part in the gantry machining center which greatly affects the machining accuracy. Four kinds of crossbeam structure for the large machining center were designed and their static and dynamic characteristics were analyzed. The optimal crossbeam structure was selected by the comprehensive performance evaluation method. Then the thicknesses of rib plates in the crossbeam were defined as the optimization parameters after conducting the sensitivity analysis. The first four natural frequencies were defined as the objective functions and the static performance and the mass were defined as the constraint conditions. The optimal sizes of the rib plates in the crossbeam were obtained by the optimization analysis. Finally the feasibility of the result was demonstrated by the simulation. The result indicated that with the mass increased only by 0.18%, the first four natural frequencies of the optimal crossbeam were increased by 19.56%, 19.45%, 19.84%, 17.05%.

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Zhang, Ye Zhi, and Liang Chen. "Theoretical Analysis of SSCC Floor System of through Truss High-Speed Railway Bridges." Advanced Materials Research 250-253 (May 2011): 1728–33. http://dx.doi.org/10.4028/www.scientific.net/amr.250-253.1728.

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In SSCC floor systems the concrete slab is composite with both steel stringers and crossbeams or only with stringers. The horizontal bending of the crossbeams of SSCC floor systems is not ignorable. From the deformation conforming condition, theoretical formulas for SSCC floor systems of double-railway bridges with two stringers are developed. The factors which influence the horizontal bending of crossbeams are discussed. Some conclusions are obtained. When the width of the SSCC floor system is given, the main factors which influence the horizontal bending of the crossbeams are the axial stress of the lower chords, the distance between the side stringers and the lower chords, and the continuous length of SSCC floor system. Increasing the horizontal inertia moment of crossbeams almost cannot reduce the horizontal bending stress of crossbeams. A slight horizontal rotation of the lower joints such as 10-4 rad can release more than 3% crossbeam end horizontal bending moment.

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Li, Yun Sheng, Yang Tian, and Yan Ling Zhang. "Local Stress Analysis of Orthotropic Steel Bridge Decks in High-Speed Railway." Advanced Materials Research 243-249 (May 2011): 1659–63. http://dx.doi.org/10.4028/www.scientific.net/amr.243-249.1659.

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Orthotropic decks are commonly used in high-speed railway bridges. Finite-element model is established by ANSYS for orthotropic steel bridge deck in this paper. Taking the standard PDL ZK live load as the train load, the local stress of the rib-to-deck joint, the rib-to-crossbeam joint, and the cut-outs of the crossbeam are analyzed respectively. Analysis results show that the stress concentration of bridge deck mainly appears at the intersecting part of the U-shaped rib, crossbeam, and bridge deck. In the whole bridge deck, the local stress level of the cut-outs in crossbeam is almost the highest, and the cut-outs is distorted seriously; the maximum stress of crossbeam cut-outs is mainly concentrated at the lower arc of the cut-outs, which is one of the positions prone to fatigue failure.

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8

Zhang, Guifu, and Richard J. Doviak. "Spaced-Antenna Interferometry to Measure Crossbeam Wind, Shear, and Turbulence: Theory and Formulation." Journal of Atmospheric and Oceanic Technology 24, no. 5 (May 1, 2007): 791–805. http://dx.doi.org/10.1175/jtech2004.1.

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Abstract The theory of measuring crossbeam wind, shear, and turbulence within the radar’s resolution volume V6 is described. Spaced-antenna weather radar interferometry is formulated for such measurements using phased-array weather radar. The formulation for a spaced-antenna interferometer (SAI) includes shear of the mean wind, allows turbulence to be anisotropic, and allows receiving beams to have elliptical cross sections. Auto- and cross-correlation functions are derived based on wave scattering by randomly distributed particles. Antenna separation, mean wind, shear, and turbulence all contribute to signal decorrelation. Crossbeam wind cannot be separated from shear, and thus crossbeam wind measurements are biased by shear. It is shown that SAI measures an apparent crossbeam wind (i.e., the angular shear of the radial wind component). Whereas the apparent crossbeam wind and turbulence within V6 cannot be separated using monostatic Doppler techniques, angular shear and turbulence can be separated using the SAI.

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9

Guo, Tie Neng, Dong Liang Guo, Li Gang Cai, Fu Ping Li, and Bin Song. "Model and Simulation of Three-Section Crossbeam Based on Experimental Data." Advanced Materials Research 199-200 (February 2011): 1262–68. http://dx.doi.org/10.4028/www.scientific.net/amr.199-200.1262.

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The modal experiment of the three-section crossbeam was carried out by single-input multi-output method. Identify the stiffness and damping with single-degree-of-freedom identification method. Use ANSYS software APDL programming language and experimental data to establish the finite element model of joint surface of three-section crossbeam. Use modal analysis method analysis the three-section crossbeam which establishes FEM modeling of joint surface. The comparison of the analysis result and experimental result are shown. The FEM result of the three-section crossbeam established FEM modeling of joint surface is basically tally with the experimental result, the modeling methods for joint surface is feasible.

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Zhang, Yi Hua, Pei Hai Hou, Tie Qun Duan, Yuan Gao, Hui Min Han, and Zhen Qi Yang. "The Analysis of Feeding Crossbeam on the Automatic Aluminous-Winding Machine." Advanced Materials Research 748 (August 2013): 336–40. http://dx.doi.org/10.4028/www.scientific.net/amr.748.336.

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The feeding crossbeam on the automatic aluminous-winding machine plays a supporting role in the preparation process of feeding pipe, the deformation of the feeding crossbeam have a direct impact on mechanical accuracy, it is difficult problem in model design, which is how to design a reasonable structure and make the crossbeam meets the requirements of strength and stiffness, as well achieve lightweight design. This article considers the complex force of crossbeam, and bases on the principle of virtual work and finite element theory, using ANASYS software to make a finite element model, the relation curves of the stress and the strain under the maximum load are summarized and the stress concentration area is found, The current study provides more reliable results to improve design.

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11

Lv, Dong Qing. "The Finite Element Analysis on the Crossbeam of Full Automatic Hydraulic Tile Press." Advanced Materials Research 605-607 (December 2012): 397–400. http://dx.doi.org/10.4028/www.scientific.net/amr.605-607.397.

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Completed the finite element static analysis on the crossbeam of a certain type of automatic hydraulic tile press and discussed stress and transfiguration of the crossbeam. The result can provide reference for design, and the discussion will be useful for mechanical engineering.

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12

Han, Wei, Li Ming Wu, Yao Hua Deng, and He Yun Zhang. "Researching a Online Method of Measuring Three-Dimensional Deformation for Large Overhead Crossbeam." Key Engineering Materials 522 (August 2012): 272–77. http://dx.doi.org/10.4028/www.scientific.net/kem.522.272.

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Aiming at the difficulty of online measurement for three-dimensional deformation of large overhead crossbeam in gantry CNC machining centre, this paper proposes a measuring method based on multi-points attitude of crossbeam-body. Real-time measuring the attitudes of some equidistant points on crossbeam-body, dealing with the measurement information by adopt shockproof filtering, wavelet denoising and smoothing. Then infer the formulas to calculate deformation of each point along different directions ofx-axis,y-axis,z-axis. The experiment uses triaxial acceleration sensor modules to measure crossbeam attitude. Experimental results show that the minimum deformational angle can be measured low to 0.06°. And if the spacing between sensor modules has mm level accuracy, the precision of calculation about deformation can reach up to 10-3mm level. In addition, this method is strongly suitable for on-site environment, and it can lay a foundation for further researching about prediction and compensation in the CNC processing.

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Gao, Li Qiang, Qian Hui Pu, Bing Han, and Zhen Biao Liu. "Comparison Study on Crossbeam Web Cutout of Different Shapes for Orthotropic Steel Bridge Deck." Applied Mechanics and Materials 238 (November 2012): 758–64. http://dx.doi.org/10.4028/www.scientific.net/amm.238.758.

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For orthotropic steel bridge deck (OSD), principle tensile stresses near the end of joint of crossbeam web and longitudinal rib and at the edge of crossbeam cutout are dependent on the shape of crossbeam cutout to a great extent. They are results of many factors, among which bending-shearing effect and in-plane supporting effect are in-plane factors, unsymmetrical loading effect and relative longitudinal deformation effect are out-of-plane factors. Comparison study on stresses at some fatigue sensitive regions of orthotropic steel deck with six types of crossbeam web cutout indicates that the top height of cutouts determines the distance between the end of joint and the neutral axis, which affects the bending effect seriously, and the area of cutouts determines the shearing effect. When OSD system is affected by bending-shearing effect, increasing the top height decreases the principle tensile stresses near the end of joint but increases the stresses at the edge of cutout, and increasing the area increases the principle tensile stresses both near the end and at the edge of cutout. When the top height of cutouts increases, the contact area between crossbeam web drops, then the principle tensile stresses near the joint produced by in-plane supporting effect increases. When the side width of cutouts increases, the constraint effect of the crossbeam web to longitudinal rib decreases, then the principle tensile stresses near the joint produced by out-of-plane effects decreases. Generally, OSD system with stiff cutouts behaves well when affected by in-plane effects, and OSD system with flexible cutouts behaves well when affected by out-of-plane effects.

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Hou, Yong Jun, Pan Fang, and Lian Zeng. "Finite Element Analysis of Dual-Frequency Vibrating Screen." Advanced Materials Research 479-481 (February 2012): 2124–28. http://dx.doi.org/10.4028/www.scientific.net/amr.479-481.2124.

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In order to study the stress distribution of dual-frequency vibrating screen and ensure the screen box has sufficient strength and longevity, a finite element model of dual-frequency vibrating screen was built, and the stress, modes and fatigue life of the screen box were analyzed. The results indicate that, the stress concentration appears at the contacting parts between the crossbeam and the stiffener of motor seat, the crossbeam, L-type stiffening plate, baffle of material added and screen box. The middle of crossbeam and the L-type stiffening plate are weaker parts of fatigue, they are easily fatigue failure under high frequency vibration.

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Cho, Dooyong, WooSeok Kim, and Sunkyu Park. "AN EXPERIMENTAL STUDY ON THE CONNECTION OF CROSSBEAMS IN A MODULAR BRIDGE." Transactions of the Canadian Society for Mechanical Engineering 37, no. 3 (September 2013): 477–89. http://dx.doi.org/10.1139/tcsme-2013-0037.

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A recently the application of modular bridge system, an assembly of the structural members, has been required to minimize traffic congestion, to reduce the period of construction, and to improve the quality and workability during the new construction and reconstruction of the bridge. For this reason, the modular bridge system is necessary to prepare for near future. In this study, alternative crossbeam system for modular prestressed concrete (PSC) T-girder bridge was developed. Static loading test was performed to inspect the structural characteristics of the alternative crossbeam system. Experimental results were analyzed and compared with each data. Therefore, the appropriate crossbeam system for modular PSC T-girder bridge was proposed.

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Zhou, Jia, X. M. Wan, Y. Li, and Q. J. Zhao. "Optimal Design and Experimental Investigations of Aluminium Extrusion Profiles for Lightweight of Car Bumper." Key Engineering Materials 585 (December 2013): 157–64. http://dx.doi.org/10.4028/www.scientific.net/kem.585.157.

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The present study aimed at developing an aluminium car bumper unit to replace the steel ones by using optimization based on experimental and FEM simulation results. The topology optimization method and response surface methodology (RSM) were applied in order to achieve an optimized design for the cross section of the crossbeam and the crash box, respectively. The three-points bending test and crash test for bumper unit were simulated to evaluate the optimization processes. The 6061 and 6063 aluminium alloy bumper unit has a weight reduction of 67% compared to the steel ones. The new extrusion dies were manufactured to produce profiles for the crossbeam and the crash box, respectively. Then the optimized extrusion profiles of crossbeam and crash box were verified by experimental studies. The performance tests were arranged to validate the experimental product. The mechanical properties of extruded aluminium crossbeam and crash box can satisfy the design requirements of products. The results indicate that the new designed unit can change the whole design of automotive parts for crash energy absorption, and definitely contribute to drastic weight reduction of steel parts.

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Yan, Zhan Hui, and Da Yi Yang. "FEM Simulation Analysis of a New-Style Slick Pole Self-Lock Up-Down Setting." Applied Mechanics and Materials 55-57 (May 2011): 1223–26. http://dx.doi.org/10.4028/www.scientific.net/amm.55-57.1223.

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A new-style slick pole self-lock up-down setting is designed to realize large size up-down of crossbeam, its principle is that crossbeam’s “limitless” pass is realized by alternate motion of an overtop elastic cannula and a ringent elastic cannula connected with poles. FEM is used to calculate proper interference value to guarantee that elastic cover can move freely when it is pressed and it can be locked when it isn’t pressed. A new-style slick pole self-lock up-down setting’s design is based on it. Simulation analysis and practical application shows that this method is feasible.

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Zhang, Ke, Ju Ping Ren, Hua Guo, Yu Hou Wu, and Kai Jun Zhao. "Crossbeam Analysis and Structure Optimization of Special-Shaped Stone Combined Machining Center." Advanced Materials Research 102-104 (March 2010): 620–24. http://dx.doi.org/10.4028/www.scientific.net/amr.102-104.620.

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With the increase of the quantity demanded, stone products with high quality, really artsy and diversification become more and more best-selling. The special-shaped stone machining equipments with numerical control, single machine intelligent, high speed, high efficiency and multi-function combination must be manufactured to produce these stone products. In this paper, 3D design and project optimization for special-shaped stone composite machining center are carried by Solid Works and innovative design. Model analysis of the crossbeam in this machining center is carried by ANSYS and the maximum deformation value in the crossbeam is found. The crossbeam structure is optimized by comparison and analysis. The design and manufacture of special-shaped stone combined machining center is very helpful for development of manufacturing.

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Guo, Tie Neng, Fang Jian Xi, Zhi Feng Liu, Qiang Cheng, and Li Gang Cai. "Simulation Analysis and Experiment Research for a Large Span and Heavy Load Crossbeam." Advanced Materials Research 211-212 (February 2011): 1210–15. http://dx.doi.org/10.4028/www.scientific.net/amr.211-212.1210.

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Aiming at solving issues of load bearing deformation compensation and sympathetic vibration, this paper takes a large span and heavy load crossbeam of a domestic heavy-type numerical control milling planer for research object, the final purpose is to improve machining precision and stability of the heavy machine tool product. The load curve considering the influence of columns deformation, natural frequency and vibration model are obtained, respectively by the dynamic and static simulation analysis of the crossbeam with the finite element analysis method. Then, the modal analysis results are verified through the model experiment. Lastly, this paper presents an approach by estimating the load curve to improve machining precision, points out the weak links, and provides guidance for crossbeam structure design, optimization and reverse manufacture.

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Wang, Quan Zhong, Chang Jiang He, and Bin Xu. "Static Finite Element Analysis of Container Flooring and Chassis Combinations." Advanced Materials Research 160-162 (November 2010): 389–94. http://dx.doi.org/10.4028/www.scientific.net/amr.160-162.389.

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We analyzed static finite element of the container flooring and chassis combination structure rolling by a car; then, we analyzed the maximum deformation and corresponding maximum stress of the flooring and chassis combination when chassis crossbeam cross-sectional shape from the U-shaped to the I-shaped and compared with the original structure with the same force, as well as the space between the central crossbeam decreased, we can see that, the appropriate crossbeam space can obviously increase the stiffness of the container and reduce the stress of the structure; at the same time, we analyzed the combinations which with different flooring structures, we can see that the difference deformation between the new combination and the original was small, so we know that the mechanical properties of flooring had little effect to the mechanical properties of the entire combination.

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Liang, Jiong, and Mei Xin Ye. "Behavior of Four-Line High-Speed Railway Bridge with Two Main Trusses and K-Shaped Brace." Advanced Materials Research 163-167 (December 2010): 148–52. http://dx.doi.org/10.4028/www.scientific.net/amr.163-167.148.

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Taking Jinan Yellow River Bridge as an example, using 3D finite element method, displacement and behavior of four-line high-speed railway bridge with two main trusses, K-shaped brace and middle suspender is studied. The results show that transversal wave of displacement of floor system is significant, and the difference of the displacement in transversal direction reaches 6 mm. The causes includes: large distance between two main trusses, large stiffness of stringers, longitudinal stiffeners and crossbeams, weak transversal stiffeners which do not connect to lower chords. About 90% of the loads are transferred to the crossbeam through path 1 and about 60% to 80% of these loads through K-shaped braces. Less than 10% of the loads transferred to lower chords through path 2.

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Qilong, Li, Guo Xuhong, Chen Yao, Ji Wenzheng, Wang Liang, and Zhang Tao. "Mechanical Analysis of Crossbeam in a Gantry Machine Tool and its Deformation Compensation." Open Mechanical Engineering Journal 9, no. 1 (April 17, 2015): 213–18. http://dx.doi.org/10.2174/1874155x01509010213.

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The beam is an important component in agantry machining center, and its deformation is believed to have asignificant impact on both the machining accuracy and the machining performance. In this research, the finite element models of a complete gantry machining center and the crossbeam are established, in whicht he restraint and boundary conditions for the finite element analysis are also introduced. It is noted thatthe impact of balance cylinders on the key components is fully considered when dealing with the force analysis. Computed results of the static characteristic analysis showed that the maximum deformation is about 0.080925 mm when crossbeam operates under different conditions. Then, the distortion curve and the compensation curve of guide rail are obtained, and the equation of a fitting compensation curve is also deduced through numerical analysis. This research is expected to provide a theoretical guide for distortion compensation of the crossbeam.

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Hoffmeister, H., A. Schertel, A. Thesen, and P. Ginauck. "New Developments in CrossBeam Technology." Microscopy and Microanalysis 12, S02 (July 31, 2006): 1244–45. http://dx.doi.org/10.1017/s1431927606065561.

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Baykal, Yahya. "Crossbeam intensity fluctuations in turbulence." Optical Engineering 53, no. 5 (May 12, 2014): 055105. http://dx.doi.org/10.1117/1.oe.53.5.055105.

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Ma, Xiao Chun, Wei Bing Shen, and Yi Qiang Zhuang. "Study on the Finite Element Numerical Simulation of Automobile Crossbeam Stamping Forming." Applied Mechanics and Materials 55-57 (May 2011): 2104–8. http://dx.doi.org/10.4028/www.scientific.net/amm.55-57.2104.

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This paper is concerned with the quantitative effect of design parameters on the stamping process of automobile crossbeam. The considered parameters in this paper are the friction coefficient, the die fillet radius and the blank holding force, which greatly affect the metal flow during stamping. Based on the finite element numerical simulation, the stamping shaped process of the automobile crossbeam is numerical simulated with the explicit finite element method with various parameters by dint of Dynaform software. According to the simulation results, the forming limit diagram(FLD) and the wall thickness distribution of cloud on the stamping processes are technologically analyzed, the reasons and control methods of wrinkling are also pointed out, and then the optimal parameter combination of the automobile crossbeam is obtained by orthogonal experiments. It is noted that the parametric study of design parameters such as µ , BHF and RD are very important in the process design of the complicated member.

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Uchida, E., O. Cunin, I. Shimoda, Y. Takubo, and T. Nakagawa. "AMS Radiocarbon Dating of Wood Samples from the Angkor Monuments, Cambodia." Radiocarbon 50, no. 3 (2008): 437–45. http://dx.doi.org/10.1017/s0033822200053534.

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In the Angkor monuments of Cambodia, pieces of wood remain (as head frames of doorways, crossbeams, ceiling boards, etc.) in the following 8 monuments: Bakong, Lolei, Baksei Chamkrong, North Khleang, Angkor Wat, Banteay Kdei, Bayon, and Gates of Angkor Thorn. Accelerator mass spectrometry (AMS) radiocarbon dating carried out on 15 wood samples collected from the above 8 monuments revealed that most of the wood samples are original, except for the head frame of a doorway in Baksei Chamkrong, the ceiling boards in the northwest tower, and a crossbeam with pivot hole in the southwest tower of the Inner Gallery of Angkor Wat. The 14C age for the head frame of a doorway in the inner wall under the central tower of North Khleang supports the hypothesis that the inner walls are additions from a later period.

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Yang, Haibo, Ping Wang, Hongliang Qian, and Pingsha Dong. "Fatigue Performance of Different Rib-To-Deck Connections Using Traction Structural Stress Method." Applied Sciences 10, no. 4 (February 12, 2020): 1239. http://dx.doi.org/10.3390/app10041239.

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The fatigue performance of an orthotropic steel bridge deck is significantly influenced by the type of the rib-to-deck connection considering the crossbeam. Fatigue fracture of the weld seam at the rib-to-deck connection has been a serious problem in such decks. In this paper, numerical models are developed for the orthotropic steel bridge decks and are analyzed for the fatigue behavior. The traction structural stress method is proven to be more accurate and effective in predicting the fatigue life. Fatigue behavior of three typical rib-to-deck connections are obtained by using traction structural stress method and by considering the effect of crossbeams. Compared to the bridge deck with weld seam of a large root, the fatigue performance of the deck with single-sided weld seam is much better with lower equivalent structural stress. The results indicate that the weld seam size should be strictly controlled for better fatigue resistance. The fatigue performance of the bridge deck with double-sided seam is significantly better than that of the bridge deck with single-sided weld seam. An increase in the thickness of the inner weld seam in the rib-to-deck connection optimizes the distribution of the equivalent structural stress and shifts the fatigue failure location from the weld root of the outer weld seam to the weld toe of the inner weld seam thus demonstrating the effect of the crossbeam. The trends of equivalent structural stress with geometric parameters of the weld seam in the rib-to-deck connection are obtained in this study. The fatigue behavior of the components and the equivalent structural stress are significantly influenced by the bridge deck thickness.

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Thesen, A., H. Hoffmeister, M. Schumann, and P. Gnauck. "Recent Developments in CrossBeam® Technology." Microscopy Today 15, no. 1 (January 2007): 18–19. http://dx.doi.org/10.1017/s1551929500051130.

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Recent developments in nano- and semiconductor technology have substantially increased the demand for accurate and efficient site specific cross-sectioning of specimens and preparation of TEM samples. Moreover, nano-research is facing new challenges for manipulation, observation, and modification of devices on a submicron scale. At the same time in materials science a new focus on analytical nanoscale investigations—not only of specimen surfaces and cross sections—but on sample volumes is emerging.These demanding requirements can be met if a focused ion beam (FIB) column for nanoscale structuring is combined with a high resolution SEM that is used to monitor the FIB milling and deposition process on a nanometer scale. Such an integrated Cross-Beam® system enables the high resolution observation and direct control of the FIB milling process in real time. Using this concept it is possible to prepare site specific TEM samples and cross sections with nano-scale accuracy. Such a system can be complemented with a gas injection system (GIS), for deposition and enhanced etching of specific materials, as well as, in-situ micro manipulation systems, and analytical detectors such as EDX and EBSP systems.

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Lu, Qinfen, Yunyue Ye, and Jianxin Shen. "Analysis and measure of novel stereo-garage driven by linear induction motor." Archives of Electrical Engineering 64, no. 4 (December 1, 2015): 669–78. http://dx.doi.org/10.1515/aee-2015-0050.

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Abstract The car access time is a key parameter, especially in a huge stereo-garage, where this one should be decreased as much as possible. This paper proposes a novel stereo-garage. Adopting the linear induction motors (LIMs), the system has a simple structure and rapid response capability. In the stereo-garage, several LIMs are installed below the crossbeam on a lifting platform, and several LIMs are fixed on the top of a moving frame. During the operation of LIMs, the moving frame moves forward and backward to reach the required parking place, whereas the crossbeam moves horizontally in order to take or store the vehicle rapidly. All these LIMs are the same and should be designed at a low frequency. The influences of key structure parameters and dynamic performances are investigated, based on FEM. The predicted results are validated by a prototype. Finally, the designed LIMs are successfully applied in two 8-layer stereo-garages.

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Kakushkin, N. "M.O. Kleinman. A case of a vaginal septum that served as an obstacle during labor. (Protocol of the meeting of the Obstetric and Gynecological Society in Kiev, book 7, 1894, p. 67)." Journal of obstetrics and women's diseases 9, no. 3 (September 22, 2020): 266. http://dx.doi.org/10.17816/jowd93266.

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Primipara 19 years old. Legs are presented (at the exit). When extracting by the leg, it turned out that the fleshy crossbeam, going from the anterior vaginal wall to the posterior one, fell into the gluteofemoral fold of the fetus and prevented the extraction of the trunk.

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Pan, Yuan. "The Fatigue Life Research on the Crossbeam of Automatic Hydraulic Tile Press." Advanced Materials Research 605-607 (December 2012): 832–36. http://dx.doi.org/10.4028/www.scientific.net/amr.605-607.832.

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Taken a certain type of crossbeam of automatic hydraulic tile press as research object, discussed its comprehensive fatigue life by using damnification-limit design method and Finite element. It provided some theory basis and reference for automatic hydraulic tile press’s safe operation and fatigue lift design.

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Mitra, A., P. Sahoo, and K. Saha. "Large Displacement of Crossbeam Structure through Energy Method." International Journal of Automotive and Mechanical Engineering 5 (June 30, 2012): 520–44. http://dx.doi.org/10.15282/ijame.5.2012.1.0042.

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Schulmeyer, Ingo. "Comprehensive Nanofabrication by Correlating Crossbeam and ORION Nanofab." Microscopy and Microanalysis 20, S3 (August 2014): 1002–3. http://dx.doi.org/10.1017/s1431927614006734.

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Schulmeyer, Ingo, and Martin Kienle. "Enabling Future Nanotomography and Nanofabrication with Crossbeam Technology." Microscopy and Microanalysis 20, S3 (August 2014): 1110–11. http://dx.doi.org/10.1017/s1431927614007284.

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Cornacchia, Giovanna, Daniele Dioni, Michela Faccoli, Claudio Gislon, Luigi Solazzi, Andrea Panvini, and Silvia Cecchel. "Experimental and Numerical Study of an Automotive Component Produced with Innovative Ceramic Core in High Pressure Die Casting (HPDC)." Metals 9, no. 2 (February 12, 2019): 217. http://dx.doi.org/10.3390/met9020217.

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Weight reduction and material substitution are increasing trends in the automotive industry. High pressure die casting (HPDC) is the conventional casting technology for the high volume production of light alloys; it has recently found wide application in the manufacturing of critical components, such as complex and thin geometry automotive parts. However, the major restriction of this affordable technology is the difficulty to design and realize hollow sections or components with undercuts. An innovative way to further increase the competitiveness of HPDC is to form complex undercut shaped parts through the use of new lost cores that are able endure the high pressures used in HPDC. This paper investigates the use of innovative ceramic lost cores in the production of a passenger car aluminum crossbeam by HPDC. Firstly, process and structural simulations were performed to improve the crossbeam design and check the technology features. The results led to the selection of the process parameters and the production of some prototypes that were finally characterized. These analyses demonstrate the feasibility of the production of hollow components by HPDC using ceramic cores.

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Lifshin, Eric, Edward L. Principe, James Evertsen, Art Dewey, Peter Gnauck, and John Friel. "Considerations for Three Dimensional Imaging In the Crossbeam FIB." Microscopy and Microanalysis 10, S02 (August 2004): 1134–35. http://dx.doi.org/10.1017/s1431927604885799.

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37

de Vaan, Michiel. "Another Frisianism in Coastal Dutch: Traam, Treem, Triem ‘Crossbeam’." Journal of Germanic Linguistics 22, no. 4 (December 2010): 315–35. http://dx.doi.org/10.1017/s1470542710000085.

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The dialect geography and etymology of Dutch, Frisian, and German trVm(e) ‘crossbeam’ suggest that western Dutch triem continues West Germanic +‑ǣ-, which underwent vowel raising to /i./ as in Frisian. Thus, Dutch traam beside triem belongs to an established group of Standard Dutch words showing /a./ next to /i./ from West Germanic +‑ǣ-, such as schraal vs. schriel. It is argued that the survival of words in /i./ in the coastal dialects of Dutch fits into recent theories that Standard Dutch is the result of language contact between medieval Frisian and Franconian.*

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Wallack, Aaron S., and John F. Canny. "Generalized Polyhedral Object Recognition and Localization Using Crossbeam Sensing." International Journal of Robotics Research 16, no. 4 (August 1997): 473–96. http://dx.doi.org/10.1177/027836499701600403.

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Liu, Qi Bo, Fang Ling Zeng, and Qiu Ju Chen. "The Research of Multi-Points Sources Signal Power Synthesis Technology." Advanced Materials Research 981 (July 2014): 402–8. http://dx.doi.org/10.4028/www.scientific.net/amr.981.402.

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This article introduces the basic principle and theory model of the crossbeam space power synthesis, and presents the result of system simulation and analysis. The author has adopted random sparse disposal and compounded the multi-points sources of transmitted power in space, through controlling the accurate orientation of the beam, reaching the aim of enhancing power. Meantime, arbitrary distributed array has been adopted to make the system more practical.

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Yang, Wen Tong, Rui Luo, Huai Qing Lu, Qiang Cheng, and Pei Hua Gu. "Load Curve Analysis and Load Errors Modeling of Long Span and Heavy Load Crossbeam." Advanced Materials Research 658 (January 2013): 475–80. http://dx.doi.org/10.4028/www.scientific.net/amr.658.475.

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An approach in obtaining the load curve and load errors of long span and heavy load crossbeam is proposed in this paper. The load curve is achieved based on the finite element analysis method, and a method for load errors modeling is constructed based on the load curve and geometric relation. This method can provide a theoretical basis for the machine precision modeling based on multi-body dynamics.

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Li, Yunhao, Juncheng Jiang, Yuan Yu, and Qingwu Zhang. "Numerical simulation of dispersion and distribution behaviors of hydrogen leakage in the garage with a crossbeam." SIMULATION 95, no. 12 (January 31, 2019): 1229–38. http://dx.doi.org/10.1177/0037549718825303.

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A three-dimensional computational fluid dynamics simulation model resolved by the unsteady Reynolds-Averaged Navier–Stokes equations was developed to predict hydrogen dispersion in an indoor environment. The effect of the height of the crossbeam (Hc) on hydrogen dispersion and distribution behaviors in a four-car garage was numerically investigated under fully confined and natural ventilation conditions. For the fully confined condition, the garage was almost completely filled with a flammable hydrogen cloud at t=600 s. In addition, the volumetric ratio of the flammable region, thickness of the hydrogen stratification, and hydrogen mole fraction all increased as Hc increased. When two symmetric ventilation openings were set up, the volumetric ratio of the flammable region decreased by 50% at t=600 s. Moreover, Hc had evident influence on the vertical distribution of hydrogen mole fraction. In addition, there existed little explosion hazard under the height of 1.6 m. The results show that Hc was a non-negligible factor for the safety design of hydrogen in the garage and Hc=0.12 m was the optimal height of the crossbeam. Furthermore, the ventilation system in the present study cannot completely eliminate the risk of hydrogen explosion. The present risk assessment results can be useful to analyze safety issues in automotive applications of hydrogen.

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Liu, Chun Fang, Qing Guang Chi, Li Mei Wang, and Qing Ding Guo. "Backstepping Adaptive Control of NC Tool Crossbeam Magnetic Levitation System." Advanced Materials Research 383-390 (November 2011): 1781–86. http://dx.doi.org/10.4028/www.scientific.net/amr.383-390.1781.

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At the moving crossbeam levitation system of the gantry NC machine tool, backstepping adaptive mode control was proposed to achieve the high precision and steady levitation of the gap due to the effect of the cutting force on magnetic levitation system. Considering that the speed state variable is nonmeasurable, a state filter K was designed to estimate the parameter on line. And then the adaptive backstepping controller is designed for the nonlinear magnetic levitation system. The system can achieve the global trajectory tracking of the output because of its unique structure and the capacity to the system disturbance, while all the signals of this closed-loop system can remain bounded via the Lyapunouv theory. The simulation results show this method can keep the stability of levitation system. Meantime, this controller has powerful ability of suppressing disturbance and high rigidity.

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Li, Lin, Zhi Jun Jiang, Qin Zhang, Sheng Tao Peng, and Hui Li. "Analysis to Causes of Concrete Transfer Crossbeam Cracks in the Basement." Applied Mechanics and Materials 578-579 (July 2014): 991–94. http://dx.doi.org/10.4028/www.scientific.net/amm.578-579.991.

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In a high-rise building located in Nanchong of Sichuan Province, after the removal of template of the crossbeam of the concrete transfer storey in the basement, there are many vertical and diagonal cracks which can be detected directly by human eyes. According to the structure design data and structural working drawing of this project, multiple detection methods are adopted for the detection on and analysis to the factors caused the cracks. From that, the thesis proposes some feasible handling suggestion as the reference for the similar engineering in future.

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Newsom, Rob K., David Ligon, Ron Calhoun, Rob Heap, Edward Cregan, and Marko Princevac. "Retrieval of Microscale Wind and Temperature Fields from Single- and Dual-Doppler Lidar Data." Journal of Applied Meteorology 44, no. 9 (September 1, 2005): 1324–45. http://dx.doi.org/10.1175/jam2280.1.

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Abstract Dual-Doppler lidar observations are used to assess the accuracy of single-Doppler retrievals of microscale wind and temperature fields in a shear-driven convective boundary layer. The retrieval algorithm, which is based on four-dimensional variational data assimilation, is applied by using dual- and single-Doppler lidar data that are acquired during the Joint Urban 2003 field experiment. The velocity field that was retrieved using single-Doppler data is compared directly with radial velocities that were measured by a second noncollocated lidar. Dual-Doppler retrievals are also performed and then compared with the single-Doppler retrieval. The linear correlation coefficient and rms deviation between the single-Doppler retrieval and the observations from the second lidar are found to be 0.94 and 1.2 m s−1, respectively. The high correlation is mainly the result of good agreement in the mean vertical structure as observed by the two lidars. Comparisons between the single- and dual-Doppler retrieval indicate that the single-Doppler retrieval underestimates the magnitude of fluctuations in the crossbeam direction. Vertical profiles of horizontally averaged correlations between the single- and dual-Doppler retrievals also show a marginal correlation (0.4–0.8) between one of the horizontal velocity components. Again, this suggests that the retrieval algorithm has difficulty estimating the crossbeam component from single-Doppler data.

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Wang, Zhaohua, Chenglong Yang, Xiaopeng Xu, Dezhuang Song, and Fenghe Wu. "Layout Design of Stiffened Plates for Large-Scale Box Structure under Moving Loads Based on Topology Optimization." Mathematical Problems in Engineering 2020 (November 10, 2020): 1–11. http://dx.doi.org/10.1155/2020/8843657.

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As the main load-bearing structure of heavy machine tools, cranes, and other high-end equipment, the large-scale box structures usually bear moving loads, and the results of direct topology optimization usually have some problems: the load transfer skeleton is difficult to identify and all working conditions are difficult to consider comprehensively. In this paper, a layout design method of stiffened plates for the large-scale box structures under moving loads based on multiworking-condition topology optimization is proposed. Based on the equivalent principle of force, the box structures are simplified into the main bending functional section, main torsional functional section, and auxiliary functional section by the magnitude of loads and moments, which can reduce the structural dimension and complexity in topology optimization. Then, the moving loads are simplified to some multiple position loads, and the comprehensive evaluation function is constructed by the compromise programming method. The mathematical model of multiworking-condition topology optimization is established to optimize the functional sections. Taking a crossbeam of superheavy turning and milling machining center as an example, optimization results show that the stiffness and strength of the crossbeam are increased by 17.39% and 19.9%, respectively, while the weight is reduced by 12.57%. It shows that the method proposed in this paper has better practicability and effectiveness for large-scale box structures.

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Ye, Xiao Yu, Kai Hua Zhang, and Wei Ping Li. "Research on Process Optimization of 560MPa Grade Sheet for Automobile Crossbeam." Advanced Materials Research 538-541 (June 2012): 3286–90. http://dx.doi.org/10.4028/www.scientific.net/amr.538-541.3286.

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In this paper, according to the problem of elongation unqualified in 560MPa grade sheet for automobile crossbeam in Pangang, through the microstructure detection、fracture observation and other methods to analysis the reason of elongation unqualified and propose process optimization measures. Used the measures, the elongation unqualified situation has obvious improvement in P560L, greatly improved qualified rate. The performance fluctuating range is small behind process optimization and have excellent forming properties and low temperature impact toughness. The users applied show that: products have excellent stamping performance, small rebound after stamping and stable quality. The various performances fully meet the used requirements of punch vertical frame in automobile.

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Gnauck, Peter, and Ulrike Zeile. "Application of the CrossBeam Technology to TEM Sample Preparation and Nanolithography." Microscopy and Microanalysis 10, S02 (August 2004): 1152–53. http://dx.doi.org/10.1017/s1431927604884411.

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Xu, Dongmei, Yingxiang Liu, Junkao Liu, and Weishan Chen. "A Bonded Type Ultrasonic Motor Using the Bending of a Crossbeam." IEEE Access 4 (2016): 1109–16. http://dx.doi.org/10.1109/access.2016.2542861.

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Fang, Heng, Nouman Iqbal, Gilles Van Staen, and Hans De Backer. "Structural optimization of rib-to-crossbeam joint in orthotropic steel decks." Engineering Structures 248 (December 2021): 113208. http://dx.doi.org/10.1016/j.engstruct.2021.113208.

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Yin, Yin An, and Xiong Hu. "Vibration Carpet Value in Classification and Evaluation of the Motor Condition." Applied Mechanics and Materials 137 (October 2011): 445–49. http://dx.doi.org/10.4028/www.scientific.net/amm.137.445.

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According to the quayside container crane, the pitch angle of the front crossbeam only can be used to classify the states of the whole crane into operating and non-operating. The Vibration Carpet Value (VCV）is presented in this paper. By means of VCV, the motor states including working and non-working can be correctly classified. Based on the classified result, by the methodology of Wavelet Packet Quantization Analysis Technique based on EMD, the real-time monitoring and evaluation of the motor condition are more correct and effective.

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Journal articles on the topic 'Crossbeam'

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