Journal articles: 'Component lifing'

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Pickard, A. C. "Component lifing." Materials Science and Technology 3, no. 9 (September 1987): 743–48. http://dx.doi.org/10.1179/mst.1987.3.9.743.

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Whitney-Rawls, Ashley, Paul Copp, Jace Carter, and Tarun Goswami. "Comparison of aero engine component lifing methods." Materials Engineering Research 4, no. 1 (2022): 201–22. http://dx.doi.org/10.25082/mer.2022.01.003.

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Failure of critical engine components such as compressor, fan, and turbine disks during flight can cause the loss of the engine, aircraft, or even life. To reduce the risk of this failure during flight, different methodologies and tools have been developed to determine the safe operating life of these critical disk components. The two most widely used lifing methods, safe-life and damage tolerance, are inherently conservative, retiring all components when a predetermined operating limit is reached. Both methods retire components with theoretical useful life remaining. Additional lifing methods can be used to reduce this conservatism and extend the life of these components. Retirement for cause, developed within the United States Air Force is a lifing method that can extend the life of components by retiring a component only when there is cause to do so. Military and industry standards on lifing methodologies were reviewed. Both deterministic and probabilistic approaches to disk lifing methods are discussed as well as current tools. This paper provides a comparison of the methodologies and tools currently being used today by both the government and industry.

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Pivovarova, M. V., and I. L. Gladkiy. "Life of gas turbine engine components under corrosive exposure." VESTNIK of Samara University. Aerospace and Mechanical Engineering 18, no. 3 (October 31, 2019): 109–17. http://dx.doi.org/10.18287/2541-7533-2019-18-3-109-117.

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Currently, operation of gas turbine engines takes place in the aggressive medium of the atmosphere of some climatic regions. As a consequence, this may cause fast degradation of the strength properties of parts of gas turbine equipment and their subsequent premature failure. The problem of determining the life of gas turbine engine components under corrosive exposure is vital. We present an analysis of the state of the art in the field of assessment of gas turbine engine component life under the influence of corrosive environment in Russia and abroad. UEC-Aviadvigatel, FSUE “VIAM” and NPO “TSKTI” JSC formulated approaches to the development of the lifing process for engine parts operating in corrosive environment.

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Korsunsky, Alexander M., Daniele Dini, and Michael J. Walsh. "Fatigue Crack Growth Rate Analysis in a Titanium Alloy." Key Engineering Materials 385-387 (July 2008): 5–8. http://dx.doi.org/10.4028/www.scientific.net/kem.385-387.5.

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Reliable prediction of fatigue crack growth rates in aerospace materials and components underpins the so-called defect-tolerant approach to lifing. In this methodology the presence or appearance of defects and cracks in components is accepted. However, safe operation is guaranteed by regular inspections and health monitoring, and ensuring (by means of reliable modelling) that no crack may grow far enough to reach the critical size in the interval between inspections. Under such circumstances it is clear that particular attention has to be paid to the development and validation of predictive modelling capabilities for fatigue crack propagation. The situation is complicated by the fact that it is often a challenge to represent correctly the in-service loading experienced by a cracked component. In practice, on top of the major cycles associated with each flight (LCF component), cycles of higher frequency and lower amplitude are also present (HCF component). Sensitivity to dwell at maximum load is also often observed. Furthermore, it is well established that complex load sequences involving overloads and underloads result in fluctuations of fatigue crack growth rates (retardation and acceleration) that must be accounted for in crack growth calculations. In the present study we consider the application of an approach due to Noroozi et al. [1] to the analysis of R-ratio effects in Ti-6Al-4V material, on the basis of the experimental crack growth rate data collected under the auspices of AGARD programme [2]. The approach shows promising results, and has the capacity to capture loading sequence effects.

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Biglari, Farid R., and Kamran M. Nikbin. "Numerical predictions of carburisation and crack evolution using a combined diffusion rate and remaining multi-axial creep ductility damage model." International Journal of Damage Mechanics 26, no. 6 (January 28, 2016): 859–80. http://dx.doi.org/10.1177/1056789516628317.

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A novel numerical damage model has been developed to combine Fick’s second law of diffusivity with microstructure modelling of environmentally assisted creep damage. The environmental acceleration of material degradation has been modelled and compared with experimental observations. The combined multi-site damage and crack growth model for creep and environmentally assisted time-dependent material oxidation/carburisation based on a gas/solid interface diffusion and non-linear time-dependent creep mechanism is proposed. Numerical predictions are presented to develop a methodology for component lifing. The model allows for the development of a hardened layer due to surface oxidation and predicts damage and cracking during subsequent creep under an applied load. The simulated grain mesh structure used can replicate surface healing or diffuse intergranular cracking and material depletion emanating from the gas/solid surface interface by quantifying the strength ratios between grain and grain boundaries. In this article, oxidation/carburisation is estimated both analytically and numerically using Fick’s diffusion laws and carbon/steel diffusion flux properties available in the literature. It is also shown that carbon diffusion distribution can be related to grain hardening due to carburisation as well as grain/grain boundary strength ratios which could vary as much as a factor of 0.5. The model is validated by comparing with actual oxidation/carburisation data for the long-term oxidised 9-12 Cr steels operating at high temperatures. Finally, it is shown that the mode and rate of surface oxidation and hardening, depending on whether the material is homogenous or contains micro-cracks substantially affects the life time of a component under high temperature creep loading.

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Busse, Christian, Frans Palmert, Paul Wawrzynek, Björn Sjödin, David Gustafsson, and Daniel Leidermark. "Crystallographic crack propagation rate in single-crystal nickelbase superalloys." MATEC Web of Conferences 165 (2018): 13012. http://dx.doi.org/10.1051/matecconf/201816513012.

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Single-crystal nickel-base superalloys are often used in the hot sections of gas turbines due to their good mechanical properties at high temperatures such as enhanced creep resistance. However, the anisotropic material properties of these materials bring many difficulties in terms of modelling and crack growth prediction. Cracks tend to switch cracking mode from Mode I cracking to crystallographic cracking. Crystallographic crack growth is often associated with a decrease in crack propagation life compared to Mode I cracking and this must be taken into account for reliable component lifing. In this paper a method to evaluate the crystallographic crack propagation rate related to a crystallographic crack driving force parameter is presented. The crystallographic crack growth rate is determined by an evaluation of heat tints on the fracture surface of a specimen subjected to fatigue loading. The complicated crack geometry including two crystallographic crack fronts is modelled in a three dimensional finite element context. The crack driving force parameter is determined by calculating anisotropic stress intensity factors along the two crystallographic crack fronts by finite-element simulations and post-processing the data in a fracture mechanics tool that resolves the stress intensity factors on the crystallographic slip planes in the slip directions. The evaluated crack propagation rate shows a good correlation for both considered crystallographic cracks fronts.

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Bache, Martin R., Christopher D. Newton, John Paul Jones, Stephen Pattison, Louise Gale, Pascual Ian Nicholson, and Eleri Weston. "Advances in Damage Monitoring Techniques for the Detection of Failure in SiCf/SiC Ceramic Matrix Composites." Ceramics 2, no. 2 (May 15, 2019): 347–71. http://dx.doi.org/10.3390/ceramics2020028.

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From a disruptive perspective, silicon carbide (SiC)-based ceramic matrix composites (CMCs) provide a considerable temperature and weight advantage over existing material systems and are increasingly finding application in aerospace, power generation and high-end automotive industries. The complex structural architecture and inherent processing artefacts within CMCs combine to induce inhomogeneous deformation and damage prior to ultimate failure. Sophisticated mechanical characterisation is vital in support of a fundamental understanding of deformation in CMCs. On the component scale, “damage tolerant” design and lifing philosophies depend upon laboratory assessments of macro-scale specimens, incorporating typical fibre architectures and matrix under representative stress-strain states. This is important if CMCs are to be utilised to their full potential within industrial applications. Bulk measurements of strain via extensometry or even localised strain gauging would fail to characterise the ensuing inhomogeneity when performing conventional mechanical testing on laboratory scaled coupons. The current research has, therefore, applied digital image correlation (DIC), electrical resistance monitoring and acoustic emission techniques to the room and high-temperature assessment of ceramic matrix composites under axial tensile and fatigue loading, with particular attention afforded to a silicon carbide fibre-reinforced silicon carbide composite (SiCf/SiC) variant. Data from these separate monitoring techniques plus ancillary use of X-ray computed tomography, in-situ scanning electron microscopy and optical inspection were correlated to monitor the onset and progression of damage during mechanical loading. The benefits of employing a concurrent, multi-technique approach to monitoring damage in CMCs are demonstrated.

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Schwagenscheidt, Markus, and Fabian Völz. "Lifting newforms to vector-valued modular forms for the Weil representation." International Journal of Number Theory 11, no. 07 (October 21, 2015): 2199–219. http://dx.doi.org/10.1142/s1793042115500980.

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Given a discriminant form D of level N, there is a natural lifting which maps elliptic modular forms of level N to vector-valued modular forms for the Weil representation associated to D. We show that in some cases the zero component of a lifting of a newform f is just a scalar multiple of f. In order to do so, we split the lifting map into certain partial liftings corresponding to the prime powers exactly dividing N and then proceed to compute the zero components of these partial maps explicitly. As an application, we show that the L-function L𝒜(f, s) of a newform f and an ideal class 𝒜 as defined by Gross and Zagier can be written as a certain L-series of the lifting of f.

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Ponidi, Ponidi, and Ali Makhfud. "Predictive Maintenance Implementation In Reach Stacker Kalmar Type Drd To Reduce Component Failure." R.E.M. (Rekayasa Energi Manufaktur) Jurnal 3, no. 1 (October 11, 2018): 29. http://dx.doi.org/10.21070/r.e.m.v3i1.1538.

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The Reach Stacker lifting tool is the most productive lifting tool for container lifting today. It can move container till 20 container box in every hour, it means that in 3 minutes it can lift and lower 1 box container. In operation the lifting equipment will surely experience a stop operation due to the failure of a component. The purpose of this study was to determine critical and important components of the history of failure data for a year (2016) in PT meratusline, by using tools Fault Tree Analysis, Failure Mode and Effect Analysis and Pareto. From the analysis, it obtained Load Handling component as the most critical component based on the most frequent failure and required a long time to repair. The cause of the failure itself was inconsistent greasing maintenance / Predictive maintenance was not executed and there was no loose handling of Load Handling chain components. From the result of research, it was suggested to make standard rule by adding greasing item in worksheet Predictive maintenance and Standard Operating Procedure Predictive Maintenance for chain replacement on Load Hadling component if already entering 12000 Hour life.

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Schupp, Sibylle. "Lifting a Butterfly – A Component-Based FFT." Scientific Programming 11, no. 4 (2003): 291–307. http://dx.doi.org/10.1155/2003/918501.

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While modern software engineering, with good reason, tries to establish the idea of reusability and the principles of parameterization and loosely coupled components even for the design of performance-critical software, Fast Fourier Transforms (FFTs) tend to be monolithic and of a very low degree of parameterization. The data structures to hold the input and output data, the element type of these data, the algorithm for computing the so-called twiddle factors, the storage model for a given set of twiddle factors, all are unchangeably defined in the so-called butterfly, restricting its reuse almost entirely. This paper shows a way to a component-based FFT by designing a parameterized butterfly. Based on the technique of lifting, this parameterization includes algorithmic and implementation issues without violating the complexity guarantees of an FFT. The paper demonstrates the lifting process for the Gentleman-Sande butterfly, i.e., the butterfly that underlies the large class of decimation-in-frequency (DIF) FFTs, shows the resulting components and summarizes the implementation of a component-based, generic DIF library in C++.

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Wrigley, Allan T., Wayne J. Albert, Kevin J. Deluzio, and Joan M. Stevenson. "Principal component analysis of lifting waveforms." Clinical Biomechanics 21, no. 6 (July 2006): 567–78. http://dx.doi.org/10.1016/j.clinbiomech.2006.01.004.

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DorMohammdi, Saber, Cody Godines, Frank Abdi, Dade Huang, Massimiliano Repupilli, and Levon Minnetyan. "Damage-tolerant composite design principles for aircraft components under fatigue service loading using multi-scale progressive failure analysis." Journal of Composite Materials 51, no. 15 (March 20, 2017): 2181–202. http://dx.doi.org/10.1177/0021998317691812.

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Virtual testing has lately gained widespread acceptance among scientists as a simple, accurate, and reproducible method to determine the mechanical properties of heterogeneous microstructures, early in the production process. As a result of the rapid expansion of the use of composites in aerospace design, virtual testing techniques are, in fact, deemed extremely useful to eliminate unnecessary tests and to reduce cost and time associated with generating allowables for lengthy lifing analyses of structures. Leveraging on a limited set of experimental data, a Progressive Failure Analysis can accurately predict the life and safety of a component/assembly, simply tapping on the physics of its micro-/macro- mechanics material properties, manufacturing processes, and service environments. The robust methodology is showcased using blind predictions of fatigue stiffness degradation and residual strength in tension and compression after fatigue compared with test data from Lockheed Martin Aeronautics and Air Force Research Laboratory). The multi-scale progressive failure analysis methodology in the GENOA software considers uncertainties and defects and evaluated the damage and fracture evolution of three IM7-977-3 laminated composite layups at room temperature. The onset and growth of composite damage was predicted and compared with X-ray CT. After blind predictions, recalibrations were performed with knowledge of the test data using the same set of inputs for all layups and simulations. Damage and fracture mechanism evolution/tracking throughout the cyclic loading is achieved by an integrated multi-scale progressive failure analysis extended FEM solution: (a) damage tracking predicts percentage contributing translaminar and interlaminar failure type, initiation, propagation, crack growth path, and observed shift in failure modes, and (b) fracture mechanics (VCCT, DCZM) predicts crack growth (Crack Tip Energy Release Rate vs. Crack Length), and delamination. The predictive methodology is verified using a building block validation strategy that uses: (a) composite material characterization and qualification (MCQ) software, and (b) the GENOA multi-scale progressive failure analysis fatigue life, stiffness degradation, and post-fatigue strength predictions for open-hole specimens under tension/compression at RTD. The unidirectional tension, compression, and in-plane shear lamina properties supplied by Lockheed Martin Aeronautics and the Air Force Research Laboratory (based on the D3039, D638, D3518 tests) were used by MCQ to reverse engineer effective fiber and matrix static and fatigue properties for the IM7-977-3 material system. The use of constituent properties identified the root cause problem for composite failure and enabled the detection of damage at the micro-scale of the material where damage is incepted. For all three case studies (namely, layups [0/45/90/−45]2s, [+60, 0, −60]3s, and [+30, +60, 90, −60, −30]2s), the blind predictions on the fatigue stiffness degradation and residual strength of the open-hole coupon in tension/compression under cyclic loading (with R = 0.1) at RTD were evaluated using a FE mesh (made of 2k shell elements), in which only one shell element, containing all plies, was employed through the thickness. The results of all analyses correlated very well with the tests, including the damage micro-graphs generated during the cyclic loading.

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Wang, Zhuozheng, John R. Deller, Kebin Jia, and Wenli Zhang. "An Improved Method of Training Overcomplete Dictionary Pair." Mathematical Problems in Engineering 2014 (2014): 1–8. http://dx.doi.org/10.1155/2014/386835.

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Training overcomplete dictionary pair is a critical step of the mainstream superresolution methods. For the high time complexity and susceptible to corruption characteristics of training dictionary, an improved method based on lifting wavelet transform and robust principal component analysis is reported. The high-frequency components of example images are estimated through wavelet coefficients of 3-tier lifting wavelet transform decomposition. Sparse coefficients are similar in multiframe images. Accordingly, the inexact augmented Lagrange multiplier method is employed to achieve robust principal component analysis in the process of imposing global constraints. Experiments reveal that the new algorithm not only reduces the time complexity preserving the clarity but also improves the robustness for the corrupted example images.

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Wang, Yan, Yu Lian Chang, Sheng Gao, and Jing Wang. "Study on Dynamics Model of Macro/Micro Mechanical Arm of the New Workover." Advanced Materials Research 538-541 (June 2012): 1002–5. http://dx.doi.org/10.4028/www.scientific.net/amr.538-541.1002.

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Macro/micro mechanical arm is an important component of workover mechanical system. According to its composition characteristics and working principle, the arm was simplified to a plane system that all components were working in the same plane. Based on rigid body kinematics and dynamics theories, the kinematics and dynamics mathematical models of arm lifting progress were established by using constraint equations, rate equation, acceleration equations, virtual principle work, lagrange multiplier and differential-algebraic mixed equations of motion. It provides theoretical basis for kinematics and dynamics analysis of the macro/micro mechanical arm in lifting process.

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Zhao, Hengtian, Junjia Du, Yayue Xu, Yujie Li, and Yingai Jin. "Study on properties and composition of ancient glass based on PCA and gradient lifting tree model." Highlights in Science, Engineering and Technology 22 (December 7, 2022): 227–33. http://dx.doi.org/10.54097/hset.v22i.3366.

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In order to help archaeologists better study ancient glass, uncover the mystery of the early Silk Road, and also better protect these cultural heritage.In this paper, the properties and composition of ancient glass are studied.All types of glass samples were analyzed by PCA principal component analysis and weighted summation, and the type characteristic equation was obtained. After calculating the candidate points iteratively in MATLAB, the optimal critical eigenvalue was set to 5, and the type judgment model was established.According to get the type of the characteristic equation, the selection is related components as high potassium and the composition of class division, choose negative correlation components as lead, barium and the composition of class division, through the PCA principal component analysis of two types of glass data are reduced to 3 d in the class we USES Kmeans clustering algorithm for two types of glass, For the sensitivity analysis of subclass partitioning, we used SOBOL global sensitivity analysis method, and obtained that principal component 1 would have the greatest impact on the model output.

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Zhang, Yitong, Yuhang Wu, Jing Sui, and Min Lee. "Strategy of Maintainable Renewal of Assembled Residential Buildings Based on PSO-ELM." Mathematical Problems in Engineering 2022 (June 9, 2022): 1–7. http://dx.doi.org/10.1155/2022/5813577.

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Based on the PSO-ELM model, we analyze the key elements of safety input to respond to accidents and construct and evaluate its resource input optimization scheme. Based on the PSO-ELM cost prediction model, we analyze the key safety inputs for accident response and construct and evaluate the optimal allocation of resources. The results show that improving the technical level of component lifting is the key point of safety management in the construction of assembled buildings; increasing the strength of safety inspection before delivery of components, enhancing the technical performance of component safety status identification, and reasonably planning the frequency of using special transportation vehicles for components are effective ways to achieve the balance of safety, schedule, and cost of the project.

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Boulabiar, Karim, and Samir Smiti. "Lifting components in clean abelian ℓ-groups." Mathematica Slovaca 68, no. 2 (April 25, 2018): 299–310. http://dx.doi.org/10.1515/ms-2017-0101.

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Abstract Let G be an abelian ℓ-group with a strong order unit u > 0. We call G u-clean after Hager, Kimber, and McGovern if every element of G can be written as a sum of a strong order unit of G and a u-component of G. We prove that G is u-clean if and only if u-components of G can be lifted modulo any ℓ-ideal of G. Moreover, we introduce a notion of u-suitable ℓ-groups (as a natural analogue of the corresponding notion in Ring Theory) and we prove that the ℓ-group G is u-clean when and only when it is u-suitable. Also, we show that if E is a vector lattice, then E is u-clean if and only if the space of all u-step functions of E is u-uniformly dense in E. As applications, we will generalize a result by Banaschewski on maximal ℓ-ideals of an archimedean bounded f-algebras to the non-archimedean case. We also extend a result by Miers on polynomially ideal C(X)-type algebras to the more general setting of bounded f-algebras.

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KAMIONKA, AGATA, ELZBIETA GRZYWACZ, and MARIUSZ LIPOWSKI. "Somatotypes of athletes with physical disabilities and the type of activity they undertake." Baltic Journal of Health and Physical Activity 12, no. 3 (September 30, 2020): 47–60. http://dx.doi.org/10.29359/bjhpa.12.3.05.

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Background: The issue of scientific measurement of somatotypes of athletes with physical disabilities and the type of physical activity undertaken by them is poorly documented in the literature. The aim of the study is to determine what type of body composition is characteristic of athletes with physical disabilities, engaging in various types of physical activity, such as swimming, sitting volleyball and weight lifting. Material and methods: Sixty men, aged 20-30, were qualified for the study. Each study participant had a motor dysfunction and was in intellectual norm. For the research protocol, Sheldon’s typology in Heath and Carter modification was used. Results: The group of men with physical disabilities practicing swimming regularly had the advantage of endomorphic and mesomorphic components. A similar distribution of components in the somatotype was demonstrated by men playing sitting volleyball. Men lifting weights clearly showed the dominance of the mesomorphic component and, to a small extent, the share of the ectomorphic and endomorphic components. Conclusions: A properly calculated somatotype allows disabled athletes to learn about body composition components and to train and develop more effectively in a particular physical activity.

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Lin, Zhen Xian, Yuan Sheng Li, and Jian Tao Li. "An Improved QIM Watermarking Algorithm." Applied Mechanics and Materials 644-650 (September 2014): 4641–44. http://dx.doi.org/10.4028/www.scientific.net/amm.644-650.4641.

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Put forward an improved QIM watermark embedding algorithm. The carrier image is transformed into YCbCr space, lifting wavelet transform the three components, then using the QIM quantization method embeds watermark into high frequency coefficients of Cb and Cr component, and Y component of low frequency coefficients. The experimental results show that embedded watermark which using improved algorithm has good invisibility. Anti attack test results show that after using common attack method attack the image embedded watermark, it can still extract the watermark completely. The anti-attack performance of improved QIM algorithm is much better than texture watermarking algorithm based on DCT.

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Harrison, G. F., and M. R. Winstone. "Modelling and lifing of structural materials for future aeroengine components." Advanced Performance Materials 3, no. 3-4 (1996): 263–78. http://dx.doi.org/10.1007/bf00136791.

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Zheng, Xue Qin, Dong Qin, and He Zhi Liu. "Application of Improved Threshold’s Lifting Wavelet to the Analysis of the Dam’s Displacement." Applied Mechanics and Materials 226-228 (November 2012): 1415–19. http://dx.doi.org/10.4028/www.scientific.net/amm.226-228.1415.

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The series of dam’s deformation data can be seen as a string of digital signal, which is composed of different frequencies. Because of the high frequency noise in the noise information, a new method of improved threshold’s lifting wavelet function is demonstrated. Using this new method to abstract components of dam monitoring data. This new method can eliminate the defect existing in traditional threshold function during the denoising process. The example shows that the lifting wavelet based on improved threshold function is more accurate and objective in the process of abstracting component compared with the traditional wavelet , which is feasible to analyze the dam performance precisely and practically. Therefore, it plays a pivotal role in the analysis of the dam performance.

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Xie, Quan Min, Huai Zhi Zhang, Ying Gao, Hong An Cao, Sheng Qiang Guo, Ming Shou Zhong, and Hao Quan Liu. "Research on Blasting Vibration Signal Denoising Based on Lifting Scheme." Applied Mechanics and Materials 713-715 (January 2015): 647–50. http://dx.doi.org/10.4028/www.scientific.net/amm.713-715.647.

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Considering lifting scheme and traditional wavelet packet transform principle, The optimal lifting wavelet packet threshold denoising algorithm was introduced. Experimental blasting vibration signal was decomposed by optimal lifting wavelet packet, and noise components in blasting vibration measured signals were filtered successfully. Research shows that, lifting wavelet package transform can effectively remove noise components, and it laid an important foundation for lifting algorithm will be introduced into the analysis field of blasting vibration effects and other mechanical vibration signal.

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Campbell-Kyureghyan, Naira H., and William S. Marras. "Cumulative Effects of Load Frequency and Velocity on the Lumbar Spine Response during a Repetitive Lifting Task." Proceedings of the Human Factors and Ergonomics Society Annual Meeting 49, no. 14 (September 2005): 1274–76. http://dx.doi.org/10.1177/154193120504901402.

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Work—related low back disorders arise from a complex interaction of events. One aspect of interest is cyclic or repetitive tasks, which are performed on a daily basis in a variety of situations, and often for extended periods of time. The specific questions to be addressed in this study are the effects of the load frequency and time-dependent material properties on the lumbar spine component behavior. The newly developed and validated, subject specific, finite element model of lumbar spine is used in conjunction with kinematic data imported from human subjects experimental testing of repetitive sagittally-symmetric lifting and lowering tasks. Creep and energy dissipation in the lumbar spine components are used to quantify the effect of lifting frequency and velocity on the potential for injury over an eight-hour workday.

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Mohammadi, Mohammad Reza Shah, Carl Richter, Daniel Pak, Carlos Rebelo, and Markus Feldmann. "Steel hybrid onshore wind towers installed with minimal effort: Development of lifting process." Wind Engineering 42, no. 4 (July 11, 2018): 335–52. http://dx.doi.org/10.1177/0309524x18777331.

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The total costs per produced kilowatt-hour for wind turbines depend significantly on the investment costs. Thereby, the tower is a relevant cost component, which depends on the chosen supporting structure, the material, and especially on the erection process. Here, an innovative erection process is presented in order to minimize the wind turbine installation, which leads to excluding the extra tall cranes for installing the wind turbines with hub heights over 180 m. In order to propose the innovative erection process, a new hybrid lattice/tubular supporting structure for the onshore wind turbines is designed. The connection component between the tubular part and lattice structure is proposed considering the support functionality for the new erection process. Furthermore, the building steps of the complete erection process are explained. The operational and the lifting loads on wind turbine supporting structure are estimated, and consequently, the erection process stages were analyzed. Finally, the finite element simulation are performed to specify the critical stresses in subcomponents of the supporting structure in each lifting stage and to show the feasibility of the erection process. Moreover, the most critical points and the stages are investigated and stress level in the supporting structure components is computed.

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Liu, Dian Ting, and Fei Fei Jia. "A Method of the Green Product Configuration Design Based on Multi-Layer Generalized Operator and Genetic Algorithm." Applied Mechanics and Materials 483 (December 2013): 542–49. http://dx.doi.org/10.4028/www.scientific.net/amm.483.542.

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Taking the configuration design of the lifting device in a bridge crane as an example, this paper discusses the green optimal design method of enterprise's modular products with uncertain factors. The multi-layer generalized operators and comprehensive mathematical model under uncertainty are established based on the mapping relationship between product function and its structure. The model is transformed to an ascertaining combinatorial optimization model by de-fuzzy operator, and then it is solved by GA (Genetic Algorithm, GA). The method of chromosome encoding in binary that the chromosome is segmented by components and the genes in each segment are ranged as corresponding structures of each component, and the methods of selection and crossover and mutation operator are presented in this paper. The result of the green configuration design on the lifting device verifies the effectiveness and practical value of the method proposed in this paper.

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Burgess, Ben. "Minimising the risk of hydrogen embrittlement (HE) and hydrogen assisted stress cracking (HASC) within steel lifting products used in the marine environment." APPEA Journal 61, no. 1 (2021): 77. http://dx.doi.org/10.1071/aj20162.

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Hydrogen embrittlement (HE) and hydrogen assisted stress cracking (HASC) are processes that detrimentally affect certain steels. These processes are understood and well documented. In recent years there has been an accumulation of product failures involving steel lifting components in the offshore industry. These failures have individually been investigated and confirmed as the result of HE and HASC. There continues to be an assumption that steel lifting components that comply with international standards are suitable for use offshore; however, the corrosive environment and effects of dynamic load amplification on lifting components in the offshore environment significantly increase their susceptibility to HE and HASC. Our intention is to provide the offshore industry with technical guidance on the correct material selection in steel lifting components, over and above the requirements of international standards, to mitigate the risk of failure caused by HE and HASC. The definition of toughness in metallurgy and lifting is the ability of the material to absorb energy and to plastically ‘deform’ without fracturing. Our research highlights that a high-grade steel’s hardness and toughness is critical.

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Lozano-Osorno, Fernando, and Oliver Hensel. "Hay Component Sieving by a Rotary Sieve with Lifting Flights." Drying Technology 32, no. 13 (August 15, 2014): 1560–67. http://dx.doi.org/10.1080/07373937.2014.907303.

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Kang, Shih-Chung, Chia-Ming Chang, Yao-Yu Yang, and Ci-Jyun Liang. "Independent hoisting system: structural components, lifting mechanism, crane control." Impact 2018, no. 5 (August 20, 2018): 59–61. http://dx.doi.org/10.21820/23987073.2018.5.59.

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Ju, Yan Zhong, Hang Zhou, and Wei Fan. "The Research for Assembling Double Circuit Steel Tube Tower with New inside Pulling Wire." Applied Mechanics and Materials 644-650 (September 2014): 4852–55. http://dx.doi.org/10.4028/www.scientific.net/amm.644-650.4852.

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Double Circuit Steel Tube Tower has a large size structural and a heavy weight of components, so the construction of tower becomes more difficult. This article uses the Midas software to simulate the Process of Inside Pulling Wire for Double Circuit Steel Tube Tower erection in windy weather and no windy weather, Researching the influence of the new lifting system and the original lifting system on the whole of lifting system. Through the stress analysis and simulation formajor rigging, we can know which lifting ways can be used when the horizontal displacement of the derrick has or has not strict restrictions, or the lifting weight has been restricted when the Wind load is too strong. New lifting system can lift very heavy tower material and has little affect by windy weather, especially suite for assembling large size structural and heavy weight of components tower.

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Yoshioka, Yomei, Daizo Saito, and Shoko Ito. "Lifing issues in hot gas path components of heavy-duty gas turbines." Materials at High Temperatures 28, no. 3 (September 2011): 188–96. http://dx.doi.org/10.3184/096034011x13123564973525.

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Ju, Jian Min. "Strength and Displacement Analysis of a Nuclear Power Giant Lifting Grid and Steel Liner." Applied Mechanics and Materials 444-445 (October 2013): 815–19. http://dx.doi.org/10.4028/www.scientific.net/amm.444-445.815.

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Construction of nuclear power plant steel liner is an important component. The design and lifting is a highly complex technical systems engineering. For a nuclear power plant project in China, the displacement and strength of the grid and the steel liner have been analyzed in the lifting process by computer methods. The results show that the use of lifting truss design has good strength and stiffness, which can achieve the requirements. The steel liner in the lifting process itself is not overstressed and deformed. The lifting process can meet the engineering requirements of the installation accuracy.

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Cong, Qian, Zhengwen Yang, Jin Xu, Boshuai Ma, Tingkun Chen, Xiaochao Zhang, Lin Wang, and Shaofeng Ru. "Design and Test of Load-Lifting Performance for Hydraulic Linkage of the High-Medium Horsepower Tractor." Applied Sciences 11, no. 20 (October 19, 2021): 9758. http://dx.doi.org/10.3390/app11209758.

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To improve the detection efficiency and safety of the tractor, the research proposed a device for detecting the loading–lifting performance of the lower link of the tractor based on the four-bar mechanism. According to the actual use requirements and the testing standards, the critical components in the device were designed. The dynamic analysis of the load-lifting device was carried out by dynamic simulation, and the component strength in the machine was checked by the finite element simulation method. The results showed that the designed device could realize the hooking and connection of the lower link without an artificial method. The average cost of the device was 5.13 s to realize the connection with the lower link, and it took 7.30 s to raise the lower hitch point to a set height, about 750 mm. The loading test showed that the device could keep the loading force of the lower link stable during the lifting process. The designed device could shorten the detection time of the tractor hydraulic linkage and improve the cost, safety, and efficiency of detection. The research could provide a reference for the design of hydraulic linkage detection devices for the large-medium horsepower tractors and help realize the intelligent detection of tractors.

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Putra Alhadi, Gustama, Din Aswan Amran Ritonga, and Junaidi Junaidi. "PENENTUAN INTERVAL WAKTU MAINTENANCE FORKLIFT TERHADAP KOMPONEN KRITIS BERDASARKAN DATA KERUSAKAN MESIN MENGGUNAKAN METODE PREVENTIVE AGE REPLACEMENT (Studi kasus: PT. XXX)." JiTEKH 9, no. 1 (March 30, 2021): 1–7. http://dx.doi.org/10.35447/jitekh.v9i1.317.

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A forklift is a lifting tool that functions to move goods from one place to another, with a short distance and a certain height, this heavy equipment is very useful because it can move very heavy goods in a vertical or horizontal direction. Problems that are often especially related to damage to unit components at PT.XXX, which are composed of the main part, namely the forklift engine. Damage to this section can result in downtime and delay in the production process which results in machine performance being less effective and efficient. Effectiveness in the production process requires the right strategy to keep the machine in operation by determining the optimal maintenance time interval using the criticality analysis method. After calculating with the criticality analysis method, it is found that the components of the hydraulic system and transmission are critical components. Furthermore, preventive replacement measures for hydraulic system components can be taken after 6800 hours of operation. The transmission component can also be done after operating for 900 hours or during an overhaul. While the inspection action for hydraulic system components is carried out after operating for 620.76 hours, the transmission component is carried out after operating for 540.39 hours. After checking and inspection, the avaibility value of the two components is above 95%, which means that the inspection can increase availability and prevent downtime in the unit and optimize the production process.

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Cui, Qun Feng, Xu Rong Li, and Jian Zhang Wang. "The Research of Using Step Function to Simulate the Step-Movement of Forklift Machine in Mechanical Engineering Based on ADAMS." Advanced Materials Research 644 (January 2013): 212–15. http://dx.doi.org/10.4028/www.scientific.net/amr.644.212.

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the movements of forklift mainly include the forward and backward of body,driving of boom cylinder to stick cylinder, flipping and lifting of stick cylinder to shovel,and the recovery of them after the completion of these actions.The paper puts forward using step function in ADAMS to simulate these movements. First, the solid modeling of a forklift established in ADAMS. And then, the step function was utilized to carry on emulation step by step. The concret form of step function is step(parameter,time1,position1,time2,position2),the parameter here is time.The component is in position1 at time1.The component is in position2 at time2.At the same time, the utilization of combined step functions ,which means multiply step functions are add to components , can realize various motions at different time.The step movement is achieved consequently

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SONG, Chun-hua, Ying-gang OU, and Qing-ting LIU. "Effect of friction between spiral component and sugarcane on sugarcane lifting." JOURNAL OF HUNAN AGRICULTURAL UNIVERSITY 38, no. 3 (February 20, 2013): 330–32. http://dx.doi.org/10.3724/sp.j.1238.2012.00330.

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Lee, Kang N. "Special Issue: Environmental Barrier Coatings." Coatings 10, no. 6 (May 27, 2020): 512. http://dx.doi.org/10.3390/coatings10060512.

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The global increase in air travel will require commercial vehicles to be more efficient than ever before. Advanced turbine hot section materials are a key technology required to keep fuel consumption and emission to a minimum. Ceramic matrix composites (CMCs) are the most promising material to revolutionize turbine hot section materials because of their excellent high-temperature properties. Rapid surface recession due to volatilization by water vapor is the Achilles heel of CMCs. Environmental barrier coatings (EBCs), which protect CMCs from water vapor, is an enabling technology for CMCs. The first CMC component entered into service in 2016 in a commercial engine, and more CMC components are scheduled to follow within the next few years. One of the most difficult challenges to CMC components is EBC durability because failure of EBC leads to a rapid reduction in CMC component life. Novel EBC chemistries, creative EBC designs, and robust processes are required to meet EBC durability challenges. Engine-relevant testing, characterization, and lifting methods need to be developed to improve EBC reliability. The aim of this Special Issue is to present recent advances in EBC technology to address current EBC challenges.

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Ge, Xu Kun, Da Wei Liu, and Long Long Zhu. "Fatigue Life Analysis of Lifting Mechanism Rod Based on Virtual Prototyping and FEM." Advanced Materials Research 680 (April 2013): 364–68. http://dx.doi.org/10.4028/www.scientific.net/amr.680.364.

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In order to calculate fatigue life of dump truck lifting mechanism’s structure components, a virtual prototyping model of lifting mechanism was built with Multi-body Dynamic Simulation Software ADAMS. The variation of applied force of lifting mechanism rod with lifting angle was obtained from dynamic analysis of lifting mechanism. A finite element (FEM) model of the rod was established using FEM Software MSC.PATRAN/NASTRAN, and its structural strength was analyzed. On this basis, S-N curve of the rod and linear cumulative damage law was combined to calculate the rod’s fatigue life with Fatigue Analysis Software MSC.Fatigue using nominal stress method. This study provided a reference for the design and improvement of the lifting mechanism.

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Starosolski, Roman. "Reversible denoising and lifting based color component transformation for lossless image compression." Multimedia Tools and Applications 79, no. 17-18 (November 3, 2019): 11269–94. http://dx.doi.org/10.1007/s11042-019-08371-w.

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Abstract An undesirable side effect of reversible color space transformation, which consists of lifting steps (LSs), is that while removing correlation it contaminates transformed components with noise from other components. Noise affects particularly adversely the compression ratios of lossless compression algorithms. To remove correlation without increasing noise, a reversible denoising and lifting step (RDLS) was proposed that integrates denoising filters into LS. Applying RDLS to color space transformation results in a new image component transformation that is perfectly reversible despite involving the inherently irreversible denoising; the first application of such a transformation is presented in this paper. For the JPEG-LS, JPEG 2000, and JPEG XR standard algorithms in lossless mode, the application of RDLS to the RDgDb color space transformation with simple denoising filters is especially effective for images in the native optical resolution of acquisition devices. It results in improving compression ratios of all those images in cases when unmodified color space transformation either improves or worsens ratios compared with the untransformed image. The average improvement is 5.0–6.0% for two out of the three sets of such images, whereas average ratios of images from standard test-sets are improved by up to 2.2%. For the efficient image-adaptive determination of filters for RDLS, a couple of fast entropy-based estimators of compression effects that may be used independently of the actual compression algorithm are investigated and an immediate filter selection method based on the detector precision characteristic model driven by image acquisition parameters is introduced.

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Nowrin, Itisha, M. Rubaiyat Hossain Mondal, Rashed Islam, and Joarder Kamruzzaman. "A Novel OFDM Format and a Machine Learning Based Dimming Control for LiFi." Electronics 10, no. 17 (August 30, 2021): 2103. http://dx.doi.org/10.3390/electronics10172103.

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This paper proposes a new hybrid orthogonal frequency division multiplexing (OFDM) form termed as DC-biased pulse amplitude modulated optical OFDM (DPO-OFDM) by combining the ideas of the existing DC-biased optical OFDM (DCO-OFDM) and pulse amplitude modulated discrete multitone (PAM-DMT). The analysis indicates that the required DC-bias for DPO-OFDM-based light fidelity (LiFi) depends on the dimming level and the components of the DPO-OFDM. The bit error rate (BER) performance and dimming flexibility of the DPO-OFDM and existing OFDM schemes are evaluated using MATLAB tools. The results show that the proposed DPO-OFDM is power efficient and has a wide dimming range. Furthermore, a switching algorithm is introduced for LiFi, where the individual components of the hybrid OFDM are switched according to a target dimming level. Next, machine learning algorithms are used for the first time to find the appropriate proportions of the hybrid OFDM components. It is shown that polynomial regression of degree 4 can reliably predict the constellation size of the DCO-OFDM component of DPO-OFDM for a given constellation size of PAM-DMT. With the component switching and the machine learning algorithms, DPO-OFDM-based LiFi is power efficient at a wide dimming range.

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de Sousa, Patricia Nascimento, Marina Brito Silva, Andrea Cristina de Lima-Pardini, and Luis Augusto Teixeira. "Resistance Strength Training’s Effects on Late Components of Postural Responses in the Elderly." Journal of Aging and Physical Activity 21, no. 2 (April 2013): 208–21. http://dx.doi.org/10.1123/japa.21.2.208.

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The effect of resistance strength training on different phases of reactive postural responses to upright-stance perturbation was assessed in elderly women. Perturbation to body balance was produced by fast arm movements aiming at lifting different loads in either certain or uncertain contexts. Results from center-of-pressure analysis showed that lifting a light load under uncertainty led to more body sway than under certainty. Resistance strength training led to short periods of body sway in the compensation phase and to decreased variability in the stabilization phase of postural responses. These results suggest that neuromuscular adaptation from resistance strength training benefits late phases of postural responses to perturbation of body balance in the elderly.

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Debras, Camille. "The shrug." Gesture 16, no. 1 (June 15, 2017): 1–34. http://dx.doi.org/10.1075/gest.16.1.01deb.

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Abstract The shrug is a widely shared gesture ensemble with several different components. These include: lifting the shoulders; rotating the forearms outwards with extended fingers to a “palm up” position; with mouth firmly closed, pulling the lips downwards (the “mouth shrug”), which may or may not be combined with raising the eyebrows and tilting the head to one side. It comprises a rich yet consistent network of forms (a single component or a combination of components can index the whole enactment). These components, together or in various combinations, are shown to express incapacity, powerlessness, indetermination, indifference, obviousness which, we suggest, are unified by a common semantic theme of personal disengagement. Since the shrug expresses pragmatic meanings and its formational and semantic core remains stable across different contexts and speakers, the shrug also qualifies as a recurrent gesture. Based on empirical evidence gathered from a videotaped corpus of dyadic interactions between native speakers of British English, this study proposes a qualitative-yet-systematic method to provide a unified account of shrugging.

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FUJINOKI, KENSUKE, and SHUNSUKE ISHIMITSU. "TRIANGULAR BIORTHOGONAL WAVELETS WITH EXTENDED LIFTING." International Journal of Wavelets, Multiresolution and Information Processing 11, no. 04 (July 2013): 1360002. http://dx.doi.org/10.1142/s0219691313600023.

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We present a new family of triangular biorthogonal wavelets that is defined on a triangular lattice by introducing a new operation to generalize two-dimensional lifting, which we call twist. The resulting filters inherit several remarkable features of the early triangular biorthogonal wavelet filters such as the hexagonal symmetry of low-pass filters, symmetrical arrangement of three high-pass filters on the lattice, and that the wavelet decomposition produces uniform energy distributions over three detail components, preserving the isotropy of decomposed images. Additionally, these filters are a biorthogonal set of truly nonseparable two-dimensional wavelet filters that have much larger support, which provides much larger portions of the total energy to three detail components of decomposed images. We show that this plays a crucial role when extracting the edge structure of an image.

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Ongalo P. N. Fedha, Huang Dong Jun, Richard Rimiru, and Lilian Singoei. "Face Expression Recognition Based on Lifting Wavelet Transform and Principle Component Analysis." Journal of Convergence Information Technology 8, no. 12 (July 31, 2013): 77–87. http://dx.doi.org/10.4156/jcit.vol8.issue12.9.

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Sadler, Erin M., Ryan B. Graham, and Joan M. Stevenson. "The personal lift-assist device and lifting technique: a principal component analysis." Ergonomics 54, no. 4 (April 2011): 392–402. http://dx.doi.org/10.1080/00140139.2011.556259.

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Liu, He Zhi, Nan Ding, Dong Qin, and Jing Yang Liu. "The Determination of Deformation Monitoring Indices Using Lifting Wavelet and Multi-Component Cloud Model." Applied Mechanics and Materials 556-562 (May 2014): 3001–5. http://dx.doi.org/10.4028/www.scientific.net/amm.556-562.3001.

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As one of the most significant indices to estimate dam behavior, the study of deformation monitoring indices has become a hot spot recently. In this paper, a method based on lifting wavelet and multi-component cloud model is proposed. For this method, the time dependent component which can evaluate the dam behavior is decomposed and reconstructed by lifting wavelet firstly. According to the time dependent component, those monitoring data which can reflect the present situation of dam could be chosen. After that, compute the deformation monitoring indices of each component based on the valid data through the multi-component cloud model. And then the deformation monitoring indices of dam as well as the certainty degrees could be acquired finally. The proposed approach is tested with cloud model based on the whole monitoring data and typical small probability method relies on 1% and 5% significance level respectively. Experimental results show that this proposed method yields an excellent performance in calculating the dam safety deformation monitoring indices, which could be utilized in actual projects.

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Yuan, Li Dong, and Xian Kun Lin. "Simulation and Topological Optimization of the Lifting Mechanism of a Dump Truck." Applied Mechanics and Materials 470 (December 2013): 271–74. http://dx.doi.org/10.4028/www.scientific.net/amm.470.271.

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Taking a heavy dump truck as the research object, multi-body analysis and movement simulation are carried out on the lifting mechanism to determine the largest lifting time of the hydraulic cylinder. The stress value of key components and corresponding lifting Angle are acquired, and the calculated results and the actually known parameters and data are compared to verify the rationality of the design of lifting mechanism. Using ABAQUS for the strength check of the triangular arm and using OptiStruct for the topology optimization of the part, the mass and the volume of the new part are reduced more than 1 time. The development of part can improve product quality, shorten development cycle and reduce costs. Key words: Lifting Mechanism, Simulation, Strength Check, Topology Optimization

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Yalcin, Sercan, Michael Scarcella, Joshua Everhart, Linsen Samuel, and Anthony Miniaci. "Clinical and Radiographic Outcomes of Total Shoulder Arthroplasty With a Nonspherical Humeral Head and Inlay Glenoid in Elite Weight Lifters: A Prospective Case Series." Orthopaedic Journal of Sports Medicine 9, no. 7 (July 1, 2021): 232596712110210. http://dx.doi.org/10.1177/23259671211021055.

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Background: Weight lifting after total shoulder arthroplasty (TSA) can place significant stresses on implants that could lead to instability, loosening, and increased wear. A TSA system with nonspherical humeral head resurfacing and inlay glenoid—which improves the biomechanics and thus reduces instability, wear, and potential loosening—may be able to tolerate repetitive loads from weight lifting. Purpose: To determine clinical and radiographic outcomes after TSA in weight lifters. Study Design: Case series; Level of evidence, 4. Methods: We prospectively enrolled 16 weight lifters (mean ± SD age, 57.2 ± 7.8 years; 15 male) undergoing primary anatomic TSA (n = 17 shoulders, 1 staged bilateral) with nonspherical humeral head resurfacing and inlay glenoid replacement for glenohumeral osteoarthritis between February 2015 and February 2019. Exclusion criteria were rotator cuff deficiency, revision TSA, post-traumatic arthritis, and inflammatory arthritis. Outcome measures included the rate of return to weight lifting, results of patient-reported outcome measures (Penn Shoulder Score, Kerlan-Jobe Orthopaedic Clinic, and 12-Item Veterans RAND Health Survey), radiographic outcomes, and complication rate. Results: Follow-up was obtained on all patients at a mean of 38 months (range, 14-63 months). All patients returned to competitive weight lifting at 15.6 ± 6.9 weeks. Compared to the preoperative weight lifting level, at last follow-up patients reported performance at the following level: lighter weight, 1 (6%); same weight, 8 (50%); heavier weight, 7 (44%). Preoperative eccentric posterior glenoid wear was common (71% Walch B2 classification; 12/17), but posterior humeral subluxation improved at follow-up according to the Walch index (mean, 55.5% preoperative vs 48.5% postoperative; P < .001) and contact point ratio (mean, 63.9% preoperative vs 50.1% postoperative; P < .001). Pre- to postoperative improvements were seen in Penn Shoulder Score (44.3 vs 82.6; P < .001), Kerlan-Jobe Orthopaedic Clinic (50.6 vs 91.1; P < .001), and 12-Item Veterans RAND Health Survey physical component score but not mental component score. No signs of radiographic loosening were detected in follow-up images, nor were there any postoperative instability episodes or revision surgeries. Conclusion: There were substantial improvements in shoulder function and a high rate of return to weight lifting after TSA with a nonspherical humeral head resurfacing and inlay glenoid component. Radiographically, the humeral head centralized on the glenoid after surgery, and there was no evidence of component loosening at a mean 38-month follow-up.

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Pozo, D., I. Borrajero, J. C. Marín, and G. B. Raga. "A numerical study of cell merger over Cuba – Part II: sensitivity to environmental conditions." Annales Geophysicae 24, no. 11 (November 21, 2006): 2793–808. http://dx.doi.org/10.5194/angeo-24-2793-2006.

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Abstract. In the first part of this study, an external 3-D ambient field (3d-field) was used to initiate a simulation (Sim1). In this paper, the influence of the 3-D field in the occurrence of the cloud merger simulated in Sim1 is studied. The surface convergence was very important to supply the lifting necessary for the development of new the convection. The interaction of the gust front from an old cloud with the environmental wind, as well as the interaction between the two gust fronts, were the main factors that enhanced the surface convergence. A favorable perturbation pressure gradient was also found to intensify this mechanism. The formation and development of a new cloud from the cloud bridge was the main feature for the occurrence of the cloud merger. The influence of the wind shear components and the relative humidity (RH) in the occurrence of the cloud merger was also analyzed. The parallel wind shear component and the large RH present in the zone of study had a positive contribution to the occurrence of the cloud merger. However, the perpendicular wind shear component did not provide the main forced lifting which would be capable of generating the new convection along the direction between interacting clouds. A high resolution simulation corroborated that the cloud merger was correctly simulated and it was not obtained by unrealistic effects due to the coarse resolution employed. It evidenced that when the horizontal resolution is improved, the life cycle of each cloud and the different processes related to their interactions are better described.

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Matteazzi, S., and F. Minoia. "Fatigue design of mechanical components in lifting appliances: stress cycles transformation." International Journal of Materials and Product Technology 19, no. 5 (2003): 374. http://dx.doi.org/10.1504/ijmpt.2003.003230.

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de Looze, M. P., J. B. J. Bussmann, I. Kingma, and H. M. Toussaint. "Different methods to estimate total power and its components during lifting." Journal of Biomechanics 25, no. 9 (September 1992): 1089–95. http://dx.doi.org/10.1016/0021-9290(92)90045-3.

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Journal articles on the topic 'Component lifing'

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