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Статті в журналах з теми "Forced Responce Analysis"

1

Nikolic, M., E. P. Petrov, and D. J. Ewins. "Coriolis Forces in Forced Response Analysis of Mistuned Bladed Disks." Journal of Turbomachinery 129, no. 4 (August 15, 2006): 730–39. http://dx.doi.org/10.1115/1.2720866.

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The problem of estimating the mutual interaction of the effects of Coriolis forces and of blade mistuning on the vibration characteristics of bladed disks is addressed in this paper. The influence of different degrees of mistuning on forced response and amplification factors are studied in the presence of Coriolis forces and then compared to their non-Coriolis counterparts using a computationally inexpensive, yet representative, model of a bladed disk. The primary objective of the study reported in this paper is to establish whether current mistuned bladed disk analyses should incorporate Coriolis effects in order to represent accurately all the significant factors that affect the forced response levels.
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Setúbal, Fábio Antônio do Nascimento, Sérgio de Souza Custódio Filho, Newton Sure Soeiro, Alexandre Luiz Amarante Mesquita, and Marcus Vinicius Alves Nunes. "Force Identification from Vibration Data by Response Surface and Random Forest Regression Algorithms." Energies 15, no. 10 (May 20, 2022): 3786. http://dx.doi.org/10.3390/en15103786.

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Several dynamic projects and fault diagnosis of mechanical structures require the knowledge of the acting external forces. However, the measurement of such forces is often difficult or even impossible; in such cases, an inverse problem must be solved. This paper proposes a force identification method that uses the response surface methodology (RSM) based on central composite design (CCD) in conjunction with a random forest regression algorithm. The procedure initially required the finite element modal model of the forced structure. Harmonic analyses were then performed with varied parameters of forces, and RSM generated a dataset containing the values of amplitude, frequency, location of forces, and vibration acceleration at several points of the structure. The dataset was used for training and testing a random forest regression model for the prediction of any location, amplitude, and frequency of the force to be identified with information on only the vibration acquisition at certain points of the structure. Numerical results showed excellent accuracy in identifying the force applied to the structure.
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Saito, Akira, and Tatsuya Suzuki. "Forced response vibration analysis of induction motor stators induced by electromagnetic forces." IFAC-PapersOnLine 55, no. 27 (2022): 155–59. http://dx.doi.org/10.1016/j.ifacol.2022.10.504.

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4

Mitra, Anirban, Prasanta Sahoo, and Kashinath Saha. "Large Amplitude Forced Vibration Analysis of Stiffened Plates Under Harmonic Excitation." International Journal of Manufacturing, Materials, and Mechanical Engineering 1, no. 2 (April 2011): 62–98. http://dx.doi.org/10.4018/ijmmme.2011040105.

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Large amplitude forced vibration behaviour of stiffened plates under harmonic excitation is studied numerically incorporating the effect of geometric non-linearity. The forced vibration analysis is carried out in an indirect way in which the dynamic system is assumed to satisfy the force equilibrium condition at peak excitation amplitude. Large amplitude free vibration analysis of the same system is carried out separately to determine the backbone curves. The mathematical formulation is based on energy principles and the set of governing equations for both forced and free vibration problems derived using Hamilton’s principle. Appropriate sets of coordinate functions are formed by following the two dimensional Gram-Schmidt orthogonalization procedure to satisfy the corresponding boundary conditions of the plate. The problem is solved by employing an iterative direct substitution method with an appropriate relaxation technique and when the system becomes computationally stiff, Broyden’s method is used. The results are furnished as frequency response curves along with the backbone curve in the dimensionless amplitude-frequency plane. Three dimensional operational deflection shape (ODS) plots and contour plots are provided in a few cases.
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david Logan, J. "Forced response of a linear hyperbolic system." Applicable Analysis 33, no. 3-4 (January 1989): 255–66. http://dx.doi.org/10.1080/00036818908839877.

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Ma, Yong Jie, Yi Du Zhang, and Xiao Ci Zhao. "Cutting Force Model of Aluminum Alloy 2014 in Turning with ANOVA Analysis." Applied Mechanics and Materials 42 (November 2010): 242–45. http://dx.doi.org/10.4028/www.scientific.net/amm.42.242.

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In the present study, aluminum alloy 2014 was selected as workpiece material, cutting forces were measured under turning conditions. Cutting parameters, the depth of cut, feed rate, the cutting speed, were considered to arrange the test research. Mathematical model of turning force was solved through response surface methodology (RSM). The fitting of response surface model for the data was studied by analysis of variance (ANOVA). The quadratic model of RSM associated with response optimization technique and composite desirability was used to find optimum values of machining parameters with respect to cutting force values. The turning force coefficients in the model were calibrated with the test results, and the suggested models of cutting forces adequately map within the limits of the cutting parameters considered. Experimental results suggested that the most cutting force among three cutting forces was main cutting force. Main influencing factor on cutting forces was obtained through cutting force models and correlation analysis. Cutting force has a significant influence on the part quality. Based on the cutting force model, a few case studies could be presented to investigate the precision machining of aluminum alloy 2014 thin walled parts.
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7

Jahng, Junghoon, Eric O. Potma, and Eun Seong Lee. "Nanoscale spectroscopic origins of photoinduced tip–sample force in the midinfrared." Proceedings of the National Academy of Sciences 116, no. 52 (December 11, 2019): 26359–66. http://dx.doi.org/10.1073/pnas.1913729116.

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When light illuminates the junction formed between a sharp metal tip and a sample, different mechanisms can contribute to the measured photoinduced force simultaneously. Of particular interest are the instantaneous force between the induced dipoles in the tip and in the sample, and the force related to thermal heating of the junction. A key difference between these 2 force mechanisms is their spectral behavior. The magnitude of the thermal response follows a dissipative (absorptive) Lorentzian line shape, which measures the heat exchange between light and matter, while the induced dipole response exhibits a dispersive spectrum and relates to the real part of the material polarizability. Because the 2 interactions are sometimes comparable in magnitude, the origin of the chemical selectivity in nanoscale spectroscopic imaging through force detection is often unclear. Here, we demonstrate theoretically and experimentally how the light illumination gives rise to the 2 kinds of photoinduced forces at the tip–sample junction in the midinfrared. We comprehensively address the origin of the spectroscopic forces by discussing cases where the 2 spectrally dependent forces are entwined. The analysis presented here provides a clear and quantitative interpretation of nanoscale chemical measurements of heterogeneous materials and sheds light on the nature of light–matter coupling in optomechanical force-based spectronanoscopy.
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You, Tian Qing, Jia Zhong Zhang, and Cong Wang. "Water Exit Dynamic Analysis of Underwater Vehicle." Applied Mechanics and Materials 50-51 (February 2011): 649–53. http://dx.doi.org/10.4028/www.scientific.net/amm.50-51.649.

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The cavity, formed at the nose part of underwater launched vehicle due to the high launching velocity, will collapse while crossing water free surface and has a great impact on the strength of vehicle structure. In order to study the effect of the cavity collapse to vehicle structure, water exit dynamic analysis has been conducted. Before that, the computational model has been established. The external load, caused by cavity collapse, is assumed to be concentrated pulse forces applied on the vehicle at different time. And the flight vehicle structure is simplified into a free-free Timoshenko beam. The Fluid Structure Interaction (FSI) effect is treated as added mass and hydrodynamic drag force varying with wet surface area, which decreases with the water exit of vehicle. The dynamic response, excited by the external load, is calculated. Result presents the necessary of taking account of FSI and the influence of time space between the two concentrated forces.
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Alligné, S., P. C. O. Silva, A. Béguin, B. Kawkabani, P. Allenbach, C. Nicolet, and F. Avellan. "Forced response analysis of hydroelectric systems." IOP Conference Series: Earth and Environmental Science 22, no. 4 (March 1, 2014): 042001. http://dx.doi.org/10.1088/1755-1315/22/4/042001.

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Zirkelback, Nicole, and Luis San Andre´s. "Finite Element Analysis of Herringbone Groove Journal Bearings: A Parametric Study." Journal of Tribology 120, no. 2 (April 1, 1998): 234–40. http://dx.doi.org/10.1115/1.2834415.

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Currently, the herringbone groove journal bearing (HGJB) has important applications in miniature rotating machines such as those found in the computer information storage industry. Grooves scribed on either the rotating or stationary member of the bearing pump the lubricating fluid inward thus generating support stiffness and improving its dynamic stability when operating concentrically. The narrow groove theory (NGT), traditionally adopted to model the concentric operation of these bearings, is limited to bearings with a large number of grooves. A finite element analysis is introduced for prediction of the static and rotordynamic forced response in HGJBs with finite numbers of grooves. Results from this analysis are then compared to available experimental data as well as to estimates from the NGT. A bearing geometry parametric study is then conducted to determine optimum rotordynamic force coefficients. A discussion on the temporal variation of the bearing reaction forces and force coefficients for a rotating journal with a small number of grooves is also presented. These changes can be significant at high operating eccentricities, possibly inducing a parametric excitation in rotating systems employing this type of bearing.
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Дисертації з теми "Forced Responce Analysis"

1

Sladojevic, Ivan. "Forced response analysis of aero-elastically coupled mistuned bladed discs." Thesis, Imperial College London, 2006. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.438210.

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Hutton, Timothy M. "Innovative Forced Response Analysis Method Applied to a Transonic Compressor." Wright State University / OhioLINK, 2003. http://rave.ohiolink.edu/etdc/view?acc_num=wright1074801945.

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White, Alex. "A quantitative analysis of hemodynamic forces on cellular response." Thesis, University of Sheffield, 2013. http://etheses.whiterose.ac.uk/5695/.

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Mechanical forces are known to be important in various physiological and pathological processes, including the development of atherosclerosis. In particular it is believed that abnormal shear stress, transduced by the vascular endothelium, is particularly important in promoting atherogenesis. However, it is still unclear to what extent the precise details of the mechanical environment to which the vascular endothelium is subjected affect its response. Therefore, a novel flow-bioreactor system has been developed which is capable of subjecting endothelial cells cultured in vitro to various mechanical parameters at similar levels to those applied in vivo. The fluid dynamics within the flow-bioreactor system has been analysed computationally to accurately quantify the mechanical forces experienced by cells cultured within the flow-bioreactor system, and a validation of the computational model used has been performed to ensure the accuracy of the results of the computational fluid dynamics analysis. The flow bioreactor system has been used to subject human endothelial cells to physiologically realistic mechanical forces for up to 24 hours. The cells were shown to realign in the direction of the shear stress and elongate in response to the application of WSS, consistent with the results shown both in other mechanical models and in vivo. A computational image processing programme has been developed to accurately quantify the morphology of cells. Quantitative analysis using this programme showed that the degree of realignment and elongation was significantly dependent on the local cell density. The enabling technologies developed during this project may help with future work aimed at elucidating the features of the mechanical environment which are important in promoting or suppressing atherogenesis.
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Dolasa, Anaita Rustom. "Computer-Aided Design Software for the Undamped Two-Dimensional Static and Dynamic Analysis of Beams and Rotors." Thesis, Virginia Tech, 1999. http://hdl.handle.net/10919/32283.

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The objective of this research work was to develop a design tool to analyze and design undamped beam and rotor systems in two dimensions. Systems modeled in two dimensions, such as beams with different moments of inertia, could produce varying responses in the each direction of motion. A coupling between the vertical and horizontal motions also exists in rotor systems mounted of fluid film bearings. The computer program called 2DBEAM has been developed to model and provide analyses of such systems in two dimensions. The tool has been based on an existing design package, BEAM9, which in its present state provides the response of beams and rotors in one plane of motion. The 2DBEAM program has the capability of performing the static response, free vibration, forced dynamic response, and frequency response analyses of a system. The Transfer Matrix Method has been used in the development of the software and an explanation of the method is included in this thesis. Mathematical problems and solutions encountered while developing 2DBEAM are also documented in this study. The code has been tested against analytical and published solutions for the types of analysis mentioned above and on coupled and uncoupled system models.
Master of Science
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Griffin, Timothy R. "Computer-Aided Design Software for Torsional Analysis." Thesis, Virginia Tech, 1998. http://hdl.handle.net/10919/36548.

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The goal of this research has been the development of an effective design tool for torsional analysis. In the hopes of achieving this goal the computer program, Torsion 1, has been created. This torsional transfer matrix program provides the user with the ability to easily model multi-rotor systems using a simple user-interface. The program is capable of modeling such components or system characteristics as continuously distributed mass, viscous and structural damping, vibration absorbers, and gear meshes with gear tooth flexibility. The analysis capabilities of the program include forcedresponse and free-vibration analyses. The forced-response analysis module is capable of determining a system’s response to a static or harmonic torsional load. The free-vibration analysis module allows is capable of determining the eigenvalues and eigenvectors for damped and undamped systems. This thesis includes an explanation of the multi-rotor transfer matrix technique employed in Torsion 1. The derivation of transfer matrices for visco-elastic vibration absorbers, pendulum absorbers, flexible gear meshes, and planetary gear trains are included in this work. Finally, the validity of the program results is verified with a set of benchmark examples.
Master of Science
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Romanov, Artyom. "Investigation and development of low-fidelity analytical models for forced response, flutter and distortion propagation analysis." Thesis, Imperial College London, 2013. http://hdl.handle.net/10044/1/24425.

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The study describes a methodology for the analysis and design of turbomachinery components at low-fidelity level. This methodology is part of a broad, object-oriented environment developed at the Rolls-Royce VUTC. The approach described in this thesis is applicable to any axial turbomachinery configuration, however, main emphasis is made on compressors. The purpose of the research is to provide the opportunity to perform forced response, flutter and other unsteady analysis without the need for the expensive CFD runs. This is particularly demanded in the early stages of the aero-engine design process or in any other cases when the detailed information of the engine is not yet available, however, a broad unsteady parametric analysis based on the existing information is needed. The model uses a linearized form of the mass, momentum and energy budgets to relate small changes in the state of the gas at several positions in the machine to known disturbances at inlet or outlet, or to known changes in the geometry. The chosen approach allows usage of an arbitrary gas model without the assumption of constant gas properties. It also provides a straightforward way to obtain a steady-state solution in a minimal amount of iterations and to evaluate the exact values of the characteristic slopes. The unsteady solution methodology represents an extended and improved Semi-Actuator Disc model. The major improvements are the real geometry application, ability to handle rotating bladerows, loss models implementation and the cascade impedance model. As the solver is linearized, the harmonic perturbations are assumed to have small amplitude compared to the steady-state data and relatively long wavelength, compared to the blade measurements. Thus contributions of several perturbation sources may be superimposed within the model. The model has a block-wise structure, where every block represents a blade or an empty duct. Non-reflecting boundary conditions are applied to the blocks boundary interfaces together with a thought-through method for the angular frequency scattering. This allows assembling a multi-bladerow domain with both rotating and stationary bladerows for the unsteady analysis. A great deal of effort has been made to connect the system to a modern and general representation of the engine geometry. This data is then used to set up the domain geometry with minimal assumptions, thus considering the changes in areas, radii and the slope of the annulus. The complex blade profile information is accessible at any moment during the computation, thus allowing using a chosen set of loss and deviation models. The model uses the same geometry database as used for the CFD and FE analysis, however, any geometry data may be overridden on demand. The model has been validated on a variety of data, from the previous publications, for forced response and flutter and from alternative solvers for distorted casings. The agreement between the calculated results and the reference data is very satisfactory, with nearly exact match for a series of idealized cases. The improvements introduced in this approach, such as cascade impedance model and the loss and deviation model package extend and complete several statements made in previous publications regarding the effect of total pressure loss and presence of the passage end reflections. The model is also validated against more complex reference cases, such as 3D CFD simulation of the LP turbine blade flutter, providing a good estimation of the damping curve slope in the low-ND region. Having a tip clearance loss model, the non-uniform casing simulations have been setup for evaluation of the relationship between the unsteady mass flow and pressure ratio perturbations. A thorough literature survey is made on the previous publications of the similar subject. The survey reviews a series of the modular systems for the axial turbomachinery analysis and then continues with the investigation of semi-empirical closures for the total pressure loss and outlet flow deviation modelling. The latter two play an essential role in this research as their implementation provides more realistic results, comparable to the heavy CFD runs. Greater part of the survey is devoted to the previous publications on various approaches for 1D and 2D unsteady turbomachinery modelling. The research completes with a thorough discussion of the features implemented and the results achieved, concluding with several future work proposals for the eventual further extension of the model as well as its applicability as a keystone for possible construction of a higher-fidelity solver. The primary programming object-oriented environment chosen for the model implementation is C++ with some parts written in FORTRAN.
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Zheng, Zhijun. "The analytical force prediction and dynamic response analysis of the Bristol H25A compressor." Thesis, This resource online, 1995. http://scholar.lib.vt.edu/theses/available/etd-01102009-063019/.

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Shrestha, Santosh. "A COMPARATIVE STUDY OF EQUIVALENT LATERAL FORCE METHOD AND RESPONSE SPECTRUM ANALYSIS IN SEISMIC DESIGN OF STRUCTURAL FRAMES." OpenSIUC, 2019. https://opensiuc.lib.siu.edu/theses/2561.

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Equivalent Lateral Force Method (ELF) and Response Spectrum Analysis (RSA) are the two most popular methods of seismic design of structures. This study aims to present a comparative study of the two methods using hand-calculated approach as well as computer analysis according to ASCE 7-10 Standards. The two methods have been compared in terms of base shear and story forces by analyzing various models for different number of stories and different support conditions. It was found that ELF gives conservative results in comparison to RSA. This result was more obvious in case of four-story frames. Hence, for structures of increased elevation, the analysis from ELF may not be sufficient.
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Chasparis, Filippos. "Vortex-induced motions of marine risers : straked force database extraction & transient response analysis." Thesis, Massachusetts Institute of Technology, 2009. http://hdl.handle.net/1721.1/50570.

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Анотація:
Thesis (S.M. in Mechanical Engineering and Naval Architecture and Marine Engineering)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 2009.
Includes bibliographical references (p. 55-58).
In part I of the thesis, we extend a methodology to extract a VIV hydrodynamic database from field data to accommodate partially straked cylinders. There are two databases, each consisting of the lift and added mass coefficients as functions of reduced velocity and amplitude of response; the first for the bare part of the riser, and the second for the straked part. First, the program VIVA together with nominal force databases obtained from laboratory hydrodynamic experiments is used in order to get an initial prediction of the riser response under a particular flow profile. The nominal databases are then altered in a systematic way until the new VIVA predicted response best matches the measured field response, thus resulting in optimal databases. In part II of the thesis, we show using experimental data on a model riser that lock-in of long flexible risers placed in sheared or uniform cross-flows is a much richer phenomenon than lock-in of flexibly-mounted rigid cylinders under similar conditions. In particular, we find that the frequency content of the riser response may be either narrow-banded around a single dominant frequency (Type I response) or distributed along a relatively broad range of frequencies (Type II response). Distinct transition from Type I to Type II response, and vice versa, can occur several times within a single experimental record. Type I responses reveal features of a quasi-periodic oscillation, often accompanied by large 3rd harmonic components in the acceleration and strain signals, increased correlation length, stable riser trajectories, and monochromatic traveling or standing waves.
(cont.) Type II responses, on the other hand, are characterized by features of chaotic oscillation with small or non-existent 3rd harmonic components in the acceleration and strain signals, reduced correlation length, and a continuous spectrum.
by Filippos Chasparis.
S.M.in Mechanical Engineering and Naval Architecture and Marine Engineering
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10

Garafolo, Nicholas Gordon. "AN EXPERIMENTAL INVESTIGATION OF MULTIPLE MODE EXCITATION OF AN INTEGRALLY BLADED DISK." University of Akron / OhioLINK, 2006. http://rave.ohiolink.edu/etdc/view?acc_num=akron1164047919.

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Книги з теми "Forced Responce Analysis"

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Karl, Owen A., United States. National Aeronautics and Space Administration., and U.S. Army Research Laboratory., eds. Forced response testing of an axi-centrifugal turboshaft engine. [Washington, DC]: National Aeronautics and Space Administration, U.S. Army Research Laboratory, 1997.

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2

Meeting, Cornwallis Group. The Cornwallis Group V: Analysis for crisis response and societal reconstruction. Clementsport, N.S: Canadian Peacekeeping Press, 2000.

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3

R, Srivastava, Mehmed O, and NASA Glenn Research Center, eds. Flutter and forced response analyses of cascades using a two-dimensional linearized Euler solver. Cleveland, Ohio: National Aeronautics and Space Administration, Glenn Research Center, 1999.

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4

S, Howe Michael, and Langley Research Center, eds. Reciprocity-based experimental determination of dynamic forces and moments: A feasibility study. Hampton, Va: National Aeronautics and Space Administration, Langley Research Center, 1994.

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5

S, Howe Michael, and Langley Research Center, eds. Reciprocity-based experimental determination of dynamic forces and moments: A feasibility study. Hampton, Va: National Aeronautics and Space Administration, Langley Research Center, 1994.

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6

S, Howe Michael, and Langley Research Center, eds. Reciprocity-based experimental determination of dynamic forces and moments: A feasibility study. Hampton, Va: National Aeronautics and Space Administration, Langley Research Center, 1994.

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7

V, Leyendecker Edgar, and Geological Survey (U.S.), eds. USGS Spectral response maps and their relationship with seismic design forces in building codes. [Denver, CO]: U.S. Geological Survey, 1995.

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8

Moret, Joëlle. The path of Somali refugees into exile: A comparative analysis of secondary movements and policy responses. Neuchâtel, Switzerland: Swiss Forum for Migration and Population Studies, 2006.

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9

R, Srivastava, and United States. National Aeronautics and Space Administration., eds. User's guide for MSAP2D: A program for unsteady aerodynamic and aeroelastic (flutter and forced response) analysis of multistage compressors and turbines : under grant NAG3-1137. [Washington, DC: National Aeronautics and Space Administration, 1996.

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10

Walter, Frost, and United States. National Aeronautics and Space Administration. Scientific and Technical Information Branch., eds. Analysis of aerodynamic coefficients using gust gradient data: Spanwise turbulence effects on airplane response. [Washington, D.C.]: National Aeronautics and Space Administration, Scientific and Technical Information Branch, 1986.

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Частини книг з теми "Forced Responce Analysis"

1

Giannini, O. "Forced Response of 2-Dof Gyroscopic Systems with Stable Eigenvalues." In Topics in Modal Analysis & Testing, Volume 9, 15–23. Cham: Springer International Publishing, 2018. http://dx.doi.org/10.1007/978-3-319-74700-2_3.

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Perumal, Shanmugam, Raghunathan Swaminathan, and Mike Christensen. "Forced Vibration Harmonic Response Analysis of Semi-mobile Crusher Station." In Lecture Notes on Multidisciplinary Industrial Engineering, 157–69. Singapore: Springer Singapore, 2019. http://dx.doi.org/10.1007/978-981-13-8468-4_14.

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3

Hong, Ling, Jun Jiang, and Jian-Qiao Sun. "Response Analysis of a Forced Duffing Oscillator with Fuzzy Uncertainty." In Advances in Intelligent Systems and Computing, 3–13. Cham: Springer International Publishing, 2014. http://dx.doi.org/10.1007/978-3-319-07494-8_1.

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Holmes, D. G., and H. A. Chuang. "2D Linearized Harmonic Euler Flow Analysis for Flutter and Forced Response." In Unsteady Aerodynamics, Aeroacoustics, and Aeroelasticity of Turbomachines and Propellers, 213–30. New York, NY: Springer New York, 1993. http://dx.doi.org/10.1007/978-1-4613-9341-2_11.

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Chowdhury, Indrajit, and Shambhu P. Dasgupta. "Dynamic Response of Bunkers and Circular Silos Under Earthquake Force." In Earthquake Analysis and Design of Industrial Structures and Infra-structures, 919–72. Cham: Springer International Publishing, 2018. http://dx.doi.org/10.1007/978-3-319-90832-8_13.

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Breunung, Thomas, and George Haller. "Time-varying Spectral Submanifolds: Analytic Calculation of Backbone Curves and Forced Response." In Nonlinear Dynamics, Volume 1, 141–42. Cham: Springer International Publishing, 2018. http://dx.doi.org/10.1007/978-3-319-74280-9_12.

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Sandul, Amy L., and Veda B. Moore. "Harm Reduction: Tipping the Balance Toward Treatment and Recovery." In Public Health Ethics Analysis, 141–52. Cham: Springer International Publishing, 2022. http://dx.doi.org/10.1007/978-3-030-92080-7_10.

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AbstractOpioid use has risen dramatically over the past 40 years. In response, federal programs and policies aimed at decreasing supply of prescription opioids have stabilized excessive prescribing. Unintended consequences of limiting the quantity of prescription opioids in the population has resulted in increased use of illicit drugs and opened a pathway of transition from misuse of pills to injection of heroin and use of potent formulations of cheap, synthetic opioids such as fentanyl. Harm reduction interventions function at the community level to provide health benefits and avoidance of harm to persons engaging in illicit and injection drug use. The Consolidated Appropriations Act of 2016 gives states, local, tribal, and territorial health departments the opportunity to use federal money to support a comprehensive set of harm reduction services. Critics of harm reduction strategies argue that formalizing and legalizing certain activities creates the perception that communities and local authorities are sanctioning or encouraging illicit/illegal drug use. Syringe services programs that provide clean needles and syringes so people who inject drugs are not forced to share or reuse injection equipment, are often at the heart of such controversy. This story addresses tensions that exist in communities grappling with harm reduction approaches to opioid and injection drug use.
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Oh, Seungin, Yongbeom Cho, Kang-Heon Lee, and Jin-Gyun Kim. "Real-Time Estimation of Unmeasured Vibro-acoustic Responses Using Inverse Force Identification Technique." In Topics in Modal Analysis & Parameter Identification, Volume 8, 77–80. Cham: Springer International Publishing, 2022. http://dx.doi.org/10.1007/978-3-031-05445-7_9.

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9

Kizilay, H. Sefa, and Ender Cigeroglu. "On the Solution of Nonlinear Algebraic Equations Following Periodic Forced Response Analysis of Nonlinear Structures Using Different Nonlinear Solvers." In Nonlinear Structures & Systems, Volume 1, 121–27. Cham: Springer International Publishing, 2020. http://dx.doi.org/10.1007/978-3-030-47626-7_20.

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Reill, Peter H. "Analogy, Comparison, and Active Living Forces: Late Enlightenment Responses to the Skeptical Critique of Causal Analysis." In The Skeptical Tradition Around 1800, 203–11. Dordrecht: Springer Netherlands, 1998. http://dx.doi.org/10.1007/978-94-017-3465-3_16.

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Тези доповідей конференцій з теми "Forced Responce Analysis"

1

Giacomelli, Enzo, Marco Passeri, Matteo Romiti, and Stefano Generosi. "Forced Responce of Cylinder Manifold for Reciprocating Compressor Applications." In ASME 8th Biennial Conference on Engineering Systems Design and Analysis. ASMEDC, 2006. http://dx.doi.org/10.1115/esda2006-95504.

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The system consisting of the reciprocating compressor and associated bottles, known as the “Cylinder manifold” may potentially be the source and location of high vibration problems. Consequently special attention must be paid to the complete simulation of the system to assure smooth and safe operation. Applicable standards specify the items to be included in the study (crosshead guides, distance pieces, cylinder flanges, joints, supports, etc.). However only a model built using manufacturing drawings and validated by site measurements can provide a sufficient accurate description of the characteristics of these critical components and therefore realistic results. Knowledge of the frequencies and amplitudes of pulsation induced shaking forces defined by acoustical simulation, internal gas forces in the cylinder, and unbalanced mechanical forces and moments allows a proper forced response analysis of the cylinder manifold system to be performed. These forces are applied to the finite element model to calculate the relevant vibrations and stress amplitudes by performing a harmonic analysis. When the dynamic stresses are out of the limits it is necessary to go back to the cylinder manifold system analysis or to the acoustical study to find a solution using different supports, with lower shaking forces, or by modifying the volume bottle design. This enables an iterative analysis of the system until all requirements have been satisfied. Additional results of a forced response analysis are the reaction forces on the cylinder and discharge volume bottle supports. When the application requires a large and heavy acoustic damping system with consequently a low mechanical natural frequency, or the compressor speed is significantly high, the possibility of mechanical resonance in the first design is very high. Therefore the execution of these studies at a very early stage of the project is fundamental. The proper solution can be found only by close cooperation between the compressor manufacturer, end user, engineering contractor and vibration specialist.
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Nikolic, M., E. P. Petrov, and D. J. Ewins. "Coriolis Forces in Forced Response Analysis of Mistuned Bladed Discs." In ASME Turbo Expo 2006: Power for Land, Sea, and Air. ASMEDC, 2006. http://dx.doi.org/10.1115/gt2006-90315.

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The problem of estimating the mutual interaction of the effects of Coriolis forces and of blade mistuning on the vibration characteristics of bladed discs is addressed in this paper. The influence of different degrees of mistuning on forced response and amplification factors are studied in the presence of Coriolis forces and then compared to their non-Coriolis counterparts using a computationally inexpensive, yet representative, model of a bladed disc. The primary objective of the study reported in this paper is to establish whether current mistuned bladed disc analyses should incorporate Coriolis effects in order to represent accurately all the significant factors that affect the forced response levels.
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Zucca, Stefano, Sergio Filippi, Fabio Droetti, and Muzio M. Gola. "Forced Response of Interlocked Vane Segments: Numerical Predictions and Experimental Results." In ASME 8th Biennial Conference on Engineering Systems Design and Analysis. ASMEDC, 2006. http://dx.doi.org/10.1115/esda2006-95551.

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Resonant vibrations affect fatigue life of vane segments. Friction damping is employed to reduce vibration amplitude. When vane segments are assembled, they are twisted so that lower platforms are in contact. The sum of displacements of the two ends of the lower platform after twisting is defined ‘interlocking’. Different ‘interlocking’ values correspond to different values of normal contact force. When interlocked vanes vibrate under external force excitation, energy is dissipated by friction forces at lower platform contacts providing damping to the system. The aim of this paper is the experimental validation of a numerical code for forced response calculation of interlocked vane segments. Since friction forces depend on relative displacements of bodies in contact, the system is nonlinear. System force response is computed by means of Harmonic Balance Method (HBM). Contact model implemented in the code is characterised by tangential and normal stiffness to take into account local compliance of the contact area. Gross slip occurs when the instantaneous ratio of tangential force to normal force is equal to the friction coefficient. Also effect of microslip is taken in account. The experimental set-up used to validate the code is made of a vane segment fixed at the outer radius to an aluminium frame and in contact with two supports at the inner radius. Comparison between the numerical predictions and experimental results is performed for different values of interlocking (i.e. force normal to the contact).
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Vasanthakumar, Parthasarathy, and Paul-Benjamin Ebel. "Forced Response Analysis of a Transonic Fan." In ASME Turbo Expo 2012: Turbine Technical Conference and Exposition. American Society of Mechanical Engineers, 2012. http://dx.doi.org/10.1115/gt2012-69867.

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The forced response of turbomachinery blades is a primary source of high cycle fatigue (HCF) failure. This paper deals with the computational prediction of blade forced response of a transonic fan stage that consists of a highly loaded rotor along with a tandem stator. In the case of a transonic fan, the forced response of the rotor due to the downstream stator assumes significance because of the transonic flow field. The objective of the present work is to determine the forced response of the rotor induced as a result of the unsteady flow field due to the downstream stator vanes. Three dimensional, Navier-Stokes flow solver TRACE is used to numerically analyse the forced response of the fan. A total of 11 resonant crossings as identified in the Campbell diagram are examined and the corresponding modeshapes are obtained from finite element modal analysis. The interaction between fluid and structure is dealt with in a loosely coupled manner based on the assumption of linear aerodynamic damping. The aerodynamic forcing is obtained by a nonlinear unsteady Navier-Stokes computation and the aerodynamic damping is obtained by a time-linearized Navier-Stokes computation. The forced response solution is obtained by the energy method allowing calculations to be performed directly in physical space. Using the modal forcing and damping, the forced response amplitude can be directly computed at the resonance crossings. For forced response solution, the equilibrium amplitude is reached when the work done on the blade by the external forcing function is equal to the work done by the system damping (aerodynamic and structural) force. A comprehensive analysis of unsteady aerodynamic forces on the rotor blade surface as a result of forced response of a highly loaded transonic fan is carried out. In addition, the correspondence between the location of high stress zones identified from the finite element analysis and the regions of high modal force identified from the CFD analysis is also discussed.
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Yang, Jingyuan, and Weiwei Zhang. "Forced response analysis of the rotor blade rows with the ROM-based aeroelastic model." In GPPS Xi'an21. GPPS, 2022. http://dx.doi.org/10.33737/gpps21-tc-25.

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A rapid method, based on the reduced order model (ROM), is developed to analyze the forced response of the rotor due to the rotor-stator interaction. The unsteady aerodynamic force acting on blades is divided into two parts according to the source. One part is due to the rotor-stator interaction, while the other is due to the blade vibration. The aerodynamic forces due to the rotor-stator interaction is regarded as excitation, while an unsteady aerodynamic force model is built to calculate the unsteady aerodynamic force by the blade vibration. Then an aeroelastic model is built via coupling the structural equation with the unsteady aerodynamic force model. The aeroelastic model is calculated with the excitation of the aerodynamic forces due to the rotor-stator interaction. The forced response for the 50% height of the NASA67 secondstage rotor is analyzed by the CFD/CSD method, the ROM method and the energy method via time domain method respectively. Compared with the energy method, the relative error of the resonant amplitude is fallen from 12.5% to 0.06% by ROM method, while the efficiency is improved by 46.36 times as compared with the CFD/CSD method. In order to discuss the influence of structural parameters, the forced response analysis is conducted by the ROM method with various mass ratios and structural frequencies. It illustrates that the effect of fluid-structure coupling is crucial to the low-massratio structure. Furthermore, the structural frequency is not exactly coincident with the excitation frequency when the response amplitude reaches its peak.
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Siewert, Christian, Lars Panning, Jo¨rg Wallaschek, and Christoph Richter. "Multiharmonic Forced Response Analysis of a Turbine Blading Coupled by Nonlinear Contact Forces." In ASME Turbo Expo 2009: Power for Land, Sea, and Air. ASMEDC, 2009. http://dx.doi.org/10.1115/gt2009-59201.

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The rotor blades of a low pressure (LP) steam turbine stage are subjected to high static and dynamic loads during operation. The static loads are mainly due to the centrifugal force and thermal strains, whereas the dynamic loads are caused by fluctuating gas forces resulting in forced vibrations of the blades. The forced vibrations can lead to high cycle fatigue (HCF) failures causing substantial damage and high maintenance effort. Thus, one of the main tasks in the design of LP steam turbine blading is the vibration amplitude reduction in order to avoid high dynamic stresses that could damage the blading. The vibration amplitudes of the blades in a LP steam turbine stage can be reduced significantly to a reasonable amount if adjacent blades are coupled by shroud contacts that reinforce the blading, see Fig. 1. Furthermore, in the case of blade vibrations, relative displacements between neighboring blades occur in the contacts and friction forces are generated that provide additional damping to the structure due to the energy dissipation caused by micro- and macroslip effects. Therefore, the coupling of the blades increases the overall mechanical damping. A three-dimensional structural dynamics model including an appropriate spatial contact model is necessary to predict the contact forces generated by the shroud contacts and to describe the vibrational behavior of the blading with sufficient accuracy. To compute the nonlinear forced vibrations of the coupled blading, the nonlinear equations of motion are solved in the frequency domain owing to the high computational efficiency of this approach. The transformation of the nonlinear equations of motion into the frequency domain can be carried out by representing the steady-state displacement in terms of its harmonic components. After that transformation, the nonlinear forced response is computed as a function of the excitation frequency in the frequency domain.
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Firrone, Christian M., Daniele Botto, and Muzio M. Gola. "Modelling a Friction Damper: Analysis of the Experimental Data and Comparison With Numerical Results." In ASME 8th Biennial Conference on Engineering Systems Design and Analysis. ASMEDC, 2006. http://dx.doi.org/10.1115/esda2006-95605.

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High cycle fatigue is one of the main causes of failure of blades in turbomachinery. The negative impact of HCF on turbomachinery blades can be reduced by dry friction vibration damping. A typical application of dry friction damping in gas turbine is the so called “underplatform damper”. In this work a ‘real life’ asymmetric underplatform damper is experimentally tested with two real blades. A static test rig is used to obtain the nonlinear frequency response function of a mock-up made with two real blades with an underplatform damper between them. This paper addresses an underplatform damper model taking into account damper rotation. The proper mathematical formulations have been developed and forced response calculation of the system have been performed. Comparison with experimental data are carried out for different values of excitation forces and for pre-load similar to real centrifugal force values.
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Park, Chan Il, and Linguo Rong. "Vibro-Acoustic Analysis of a Simple Gear Box." In ASME 2013 International Design Engineering Technical Conferences and Computers and Information in Engineering Conference. American Society of Mechanical Engineers, 2013. http://dx.doi.org/10.1115/detc2013-12284.

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Mesh forces of helical gears produce forces and moments in bearings, which generate the housing vibration, and noise radiates. It is difficult to know the noise contribution of a gear box, because the gear box usually has very complex geometry. This work used a cylindrical shell-type gear box with end circular plates to understand the noise and vibration characteristics of a simple gear box and investigated the noise and the vibration of the helical gear box due to the force excitation. The helical gear box of this study consisted of a pairs of helical gears, shafts, bearings, and a gear box. Finite element analysis for the helical gear box calculated mode shapes and natural frequencies and the forced harmonic response by the commercial software. The models were validated by the impact test. Using the forced harmonic response, acoustic analysis was conducted by the commercial software and relations on vibration and noise were discussed.
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Ahmed, Rizwan, Christian Maria Firrone, and Stefano Zucca. "Experimental Investigation of Three-Dimensional Shroud Contact Forces in Forced-Vibration Testing of a Shrouded Blade." In ASME Turbo Expo 2022: Turbomachinery Technical Conference and Exposition. American Society of Mechanical Engineers, 2022. http://dx.doi.org/10.1115/gt2022-84205.

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Abstract Low Pressure Turbine (LPT) blades encounter highly stressed forced vibrations driven by centrifugal force and steady/unsteady aerodynamic loads. To prevent the blades from failure due to high cycle fatigue (HCF), the amplitude of these vibrations must be estimated and reduced. Friction damping devices like under-platform dampers, shrouds and snubbers are usually implemented to lessen these blade vibration amplitudes. For adjacent shrouded blades coupled to each other at the blade tips, the blade vibration levels are strongly affected by the three-dimensional periodic contact forces at shrouds resulting in energy dissipation due to friction. Therefore, to experimentally validate the numerical contact models that predict nonlinear forced response of shrouded blades, it is equally important to measure the contact forces acting at the shrouds. This study outlines the development and commissioning of an experimental test rig that allows the measurement of three-dimensional shroud contact forces and the forced response of the shrouded blade simultaneously. Firstly, the design requirements of the experimental setup that were considered while deciding the test rig components, are highlighted. The test rig comprises of a pair of tri-directional contact force transducers in contact with the two shroud ends of a dummy blade and includes a blade twisting mechanism for the application of the normal preload. The employed tri-directional contact force transducers consist of three uniaxial strain gauge-based force sensors, arranged in a tripod configuration, and attached to a reference block that accommodates the shroud. The calibration and the decoupling procedure of the tri-directional contact force measurement system is then briefly described. This is followed by the details of the experimental process to acquire the forced response and three-dimensional shroud contact forces simultaneously for a specified frequency range determined by a prior experimental modal analysis of the blade and test rig. Subsequently, the effects of the variation in shroud normal preload and excitation force on measured response and shroud contact forces are also discussed. Finally, the results demonstrate how the proposed experimental test rig provides a thorough understanding of the dynamic response of the shrouded blade and shroud contact forces which will lead to a more reliable experimental validation of simulation tools and its effect on system dynamics.
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Yu, L., T. H. T. Chan, J. H. Zhu, and M. Z. Chen. "A MOM-Based Algorithm for Identification of Moving Vehicle Loads on Bridges." In ASME 8th Biennial Conference on Engineering Systems Design and Analysis. ASMEDC, 2006. http://dx.doi.org/10.1115/esda2006-95672.

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An improved time domain method (ITDM) is proposed for moving force identification using bridge responses, which aims at an acceptable solution to the ill-conditioning problem that often exists in the inverse problem of moving force identification. Based on the method of moments (MOM) and the theory of moving force identification, the moving forces were described as a combination of whole basis functions, such as orthogonal Legendre polynomials or Fourier series, and were then estimated by solving the new system equations developed based on the basis functions. Under a number of response combination cases, the moving vehicle loads are identified using the ITDM and compared with the existing time domain method (TDM). Further a laboratory study was conducted to evaluate the effect of various parameters on the ITDM. Those parameters include basis function number, mode number, number of measured stations, and CPU executive time of the ITDM. Simulation and experiment results show that the ITDM has higher identification accuracy and robust noise immunity as well as being able to generate an acceptable solution to the ill-conditioning problem to some extent when it is used to identify the moving forces from bridge responses. Meanwhile, the ITDM can lessen the executive CPU time as well as being more flexible when compared with the TDM. This is beneficial to real time analysis of moving force identification in field.
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Звіти організацій з теми "Forced Responce Analysis"

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Paul W. Reimus and Marc J. Haga. Analysis of tracer responses in the BULLION Forced-Gradient Experiment at Pahute Mesa, Nevada. Office of Scientific and Technical Information (OSTI), October 1999. http://dx.doi.org/10.2172/752365.

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Chang, Arturo, Thomas Ferguson, Jacob Rothschild, and Benjamin I. Page. Ambivalence About International Trade in Open- and Closed-ended Survey Responses. Institute for New Economic Thinking Working Paper Series, September 2021. http://dx.doi.org/10.36687/inetwp162.

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Spontaneous, open-ended survey responses can sometimes better reveal what is actually on people’s minds than small sets of forced-choice, closed questions. Our analysis of closed questions and trade-related open-ended responses to 2016 ANES “likes” and “dislikes” prompts indicate that Americans held considerably more complex, more ambivalent, and – in many cases – more negative views of international trade than has been apparent in studies that focus only on closed-ended responses. This paper suggests that contrast between open- and closed-question data may help explain why the effectiveness of Donald Trump’s appeals to trade resentments surprised many observers.
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Gunay, Selim, Fan Hu, Khalid Mosalam, Arpit Nema, Jose Restrepo, Adam Zsarnoczay, and Jack Baker. Blind Prediction of Shaking Table Tests of a New Bridge Bent Design. Pacific Earthquake Engineering Research Center, University of California, Berkeley, CA, November 2020. http://dx.doi.org/10.55461/svks9397.

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Considering the importance of the transportation network and bridge structures, the associated seismic design philosophy is shifting from the basic collapse prevention objective to maintaining functionality on the community scale in the aftermath of moderate to strong earthquakes (i.e., resiliency). In addition to performance, the associated construction philosophy is also being modernized, with the utilization of accelerated bridge construction (ABC) techniques to reduce impacts of construction work on traffic, society, economy, and on-site safety during construction. Recent years have seen several developments towards the design of low-damage bridges and ABC. According to the results of conducted tests, these systems have significant potential to achieve the intended community resiliency objectives. Taking advantage of such potential in the standard design and analysis processes requires proper modeling that adequately characterizes the behavior and response of these bridge systems. To evaluate the current practices and abilities of the structural engineering community to model this type of resiliency-oriented bridges, the Pacific Earthquake Engineering Research Center (PEER) organized a blind prediction contest of a two-column bridge bent consisting of columns with enhanced response characteristics achieved by a well-balanced contribution of self-centering, rocking, and energy dissipation. The parameters of this blind prediction competition are described in this report, and the predictions submitted by different teams are analyzed. In general, forces are predicted better than displacements. The post-tension bar forces and residual displacements are predicted with the best and least accuracy, respectively. Some of the predicted quantities are observed to have coefficient of variation (COV) values larger than 50%; however, in general, the scatter in the predictions amongst different teams is not significantly large. Applied ground motions (GM) in shaking table tests consisted of a series of naturally recorded earthquake acceleration signals, where GM1 is found to be the largest contributor to the displacement error for most of the teams, and GM7 is the largest contributor to the force (hence, the acceleration) error. The large contribution of GM1 to the displacement error is due to the elastic response in GM1 and the errors stemming from the incorrect estimation of the period and damping ratio. The contribution of GM7 to the force error is due to the errors in the estimation of the base-shear capacity. Several teams were able to predict forces and accelerations with only moderate bias. Displacements, however, were systematically underestimated by almost every team. This suggests that there is a general problem either in the assumptions made or the models used to simulate the response of this type of bridge bent with enhanced response characteristics. Predictions of the best-performing teams were consistently and substantially better than average in all response quantities. The engineering community would benefit from learning details of the approach of the best teams and the factors that caused the models of other teams to fail to produce similarly good results. Blind prediction contests provide: (1) very useful information regarding areas where current numerical models might be improved; and (2) quantitative data regarding the uncertainty of analytical models for use in performance-based earthquake engineering evaluations. Such blind prediction contests should be encouraged for other experimental research activities and are planned to be conducted annually by PEER.
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Bourgeois, Paul, Bradley Kelley, John Petrusky, John Williamson, and Jonathan Yi. Transportation Analysis Exploring Alternative Shipping of Marine Expeditionary Brigade Forces to Seabase in Contingency Response Scenarios. Fort Belvoir, VA: Defense Technical Information Center, December 2015. http://dx.doi.org/10.21236/ad1009271.

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Jordan, Preston D., Curtis M. Oldenburg, and Grace W. Su. Analysis of Aquifer Response, Groundwater Flow, and PlumeEvolution at Site OU 1, Former Fort Ord, California. Office of Scientific and Technical Information (OSTI), February 2005. http://dx.doi.org/10.2172/877324.

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Barrera, Victor, Alexis Villacis, Jeffrey Alwang, and Luis Escudero. Open configuration options New Products, New Markets: Dragon Fruit in Ecuador. Inter-American Development Bank, January 2022. http://dx.doi.org/10.18235/0003964.

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Expanding incomes in Asian countries and changes in fresh-fruit value chains have created an important niche for producers of dragon fruit. Ecuadorean producers have responded and taken advantage of these evolving opportunities and market dynamism. By customizing their products to the specific demands of target markets and complying with the standards imposed by modern buyers, Ecuadorian exporters of dragon fruit demonstrate how challenges related to and opportunities in agri-food markets evolution can be met. This study documents the development of the dragon fruit market in Ecuador, with a special emphasis on the analysis of its value chain. The study additionally identifies and analyzes the main drivers of the success of the production and exports of the fruit and examines the main challenges and needs for improved public policies to promote sustainable growth of the sector. Findings are complemented with interviews conducted with the principal actors in the Ecuadorian dragon fruit industry, as well as a case study that involves several relatively recently formed dragon fruit-producing companies in the Amazon region of the country.
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Galili, Naftali, Roger P. Rohrbach, Itzhak Shmulevich, Yoram Fuchs, and Giora Zauberman. Non-Destructive Quality Sensing of High-Value Agricultural Commodities Through Response Analysis. United States Department of Agriculture, October 1994. http://dx.doi.org/10.32747/1994.7570549.bard.

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The objectives of this project were to develop nondestructive methods for detection of internal properties and firmness of fruits and vegetables. One method was based on a soft piezoelectric film transducer developed in the Technion, for analysis of fruit response to low-energy excitation. The second method was a dot-matrix piezoelectric transducer of North Carolina State University, developed for contact-pressure analysis of fruit during impact. Two research teams, one in Israel and the other in North Carolina, coordinated their research effort according to the specific objectives of the project, to develop and apply the two complementary methods for quality control of agricultural commodities. In Israel: An improved firmness testing system was developed and tested with tropical fruits. The new system included an instrumented fruit-bed of three flexible piezoelectric sensors and miniature electromagnetic hammers, which served as fruit support and low-energy excitation device, respectively. Resonant frequencies were detected for determination of firmness index. Two new acoustic parameters were developed for evaluation of fruit firmness and maturity: a dumping-ratio and a centeroid of the frequency response. Experiments were performed with avocado and mango fruits. The internal damping ratio, which may indicate fruit ripeness, increased monotonically with time, while resonant frequencies and firmness indices decreased with time. Fruit samples were tested daily by destructive penetration test. A fairy high correlation was found in tropical fruits between the penetration force and the new acoustic parameters; a lower correlation was found between this parameter and the conventional firmness index. Improved table-top firmness testing units, Firmalon, with data-logging system and on-line data analysis capacity have been built. The new device was used for the full-scale experiments in the next two years, ahead of the original program and BARD timetable. Close cooperation was initiated with local industry for development of both off-line and on-line sorting and quality control of more agricultural commodities. Firmalon units were produced and operated in major packaging houses in Israel, Belgium and Washington State, on mango and avocado, apples, pears, tomatoes, melons and some other fruits, to gain field experience with the new method. The accumulated experimental data from all these activities is still analyzed, to improve firmness sorting criteria and shelf-life predicting curves for the different fruits. The test program in commercial CA storage facilities in Washington State included seven apple varieties: Fuji, Braeburn, Gala, Granny Smith, Jonagold, Red Delicious, Golden Delicious, and D'Anjou pear variety. FI master-curves could be developed for the Braeburn, Gala, Granny Smith and Jonagold apples. These fruits showed a steady ripening process during the test period. Yet, more work should be conducted to reduce scattering of the data and to determine the confidence limits of the method. Nearly constant FI in Red Delicious and the fluctuations of FI in the Fuji apples should be re-examined. Three sets of experiment were performed with Flandria tomatoes. Despite the complex structure of the tomatoes, the acoustic method could be used for firmness evaluation and to follow the ripening evolution with time. Close agreement was achieved between the auction expert evaluation and that of the nondestructive acoustic test, where firmness index of 4.0 and more indicated grade-A tomatoes. More work is performed to refine the sorting algorithm and to develop a general ripening scale for automatic grading of tomatoes for the fresh fruit market. Galia melons were tested in Israel, in simulated export conditions. It was concluded that the Firmalon is capable of detecting the ripening of melons nondestructively, and sorted out the defective fruits from the export shipment. The cooperation with local industry resulted in development of automatic on-line prototype of the acoustic sensor, that may be incorporated with the export quality control system for melons. More interesting is the development of the remote firmness sensing method for sealed CA cool-rooms, where most of the full-year fruit yield in stored for off-season consumption. Hundreds of ripening monitor systems have been installed in major fruit storage facilities, and being evaluated now by the consumers. If successful, the new method may cause a major change in long-term fruit storage technology. More uses of the acoustic test method have been considered, for monitoring fruit maturity and harvest time, testing fruit samples or each individual fruit when entering the storage facilities, packaging house and auction, and in the supermarket. This approach may result in a full line of equipment for nondestructive quality control of fruits and vegetables, from the orchard or the greenhouse, through the entire sorting, grading and storage process, up to the consumer table. The developed technology offers a tool to determine the maturity of the fruits nondestructively by monitoring their acoustic response to mechanical impulse on the tree. A special device was built and preliminary tested in mango fruit. More development is needed to develop a portable, hand operated sensing method for this purpose. In North Carolina: Analysis method based on an Auto-Regressive (AR) model was developed for detecting the first resonance of fruit from their response to mechanical impulse. The algorithm included a routine that detects the first resonant frequency from as many sensors as possible. Experiments on Red Delicious apples were performed and their firmness was determined. The AR method allowed the detection of the first resonance. The method could be fast enough to be utilized in a real time sorting machine. Yet, further study is needed to look for improvement of the search algorithm of the methods. An impact contact-pressure measurement system and Neural Network (NN) identification method were developed to investigate the relationships between surface pressure distributions on selected fruits and their respective internal textural qualities. A piezoelectric dot-matrix pressure transducer was developed for the purpose of acquiring time-sampled pressure profiles during impact. The acquired data was transferred into a personal computer and accurate visualization of animated data were presented. Preliminary test with 10 apples has been performed. Measurement were made by the contact-pressure transducer in two different positions. Complementary measurements were made on the same apples by using the Firmalon and Magness Taylor (MT) testers. Three-layer neural network was designed. 2/3 of the contact-pressure data were used as training input data and corresponding MT data as training target data. The remaining data were used as NN checking data. Six samples randomly chosen from the ten measured samples and their corresponding Firmalon values were used as the NN training and target data, respectively. The remaining four samples' data were input to the NN. The NN results consistent with the Firmness Tester values. So, if more training data would be obtained, the output should be more accurate. In addition, the Firmness Tester values do not consistent with MT firmness tester values. The NN method developed in this study appears to be a useful tool to emulate the MT Firmness test results without destroying the apple samples. To get more accurate estimation of MT firmness a much larger training data set is required. When the larger sensitive area of the pressure sensor being developed in this project becomes available, the entire contact 'shape' will provide additional information and the neural network results would be more accurate. It has been shown that the impact information can be utilized in the determination of internal quality factors of fruit. Until now,
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8

Hernández, Beatriz. Modernising the EU-Chile Association Agreement: strengthening an alliance for social inclusion and environmental sustainability. Fundación Carolina, May 2022. http://dx.doi.org/10.33960/issn-e.1885-9119.dtff05en.

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This research paper analyzes the results of the Association Agreement (AA) between the European Union and Chile, which entered into force in 2003, up to the present time when its modernization is being negotiated. After 19 years of the agreement, the international context has changed both in its political and economic dimensions, so it is important to analyze what role these agreements can have in the face of the challenges of the post-pandemic recovery and the objectives of both regions in terms of strategic autonomy, in the geopolitical field, and in the transition towards new development models that respond to shared challenges such as climate change, ecological transition, digitalization, social inclusion or the revitalization of multilateralism.
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9

Raja, Rameez Ali, Mustafa Kilic, Monica Prezzi, Rodrigo Salgado, and Fei Han. Implementation Study: Continuous, Wireless Data Collection and Monitoring of the Sagamore Parkway Bridge. Purdue University, 2022. http://dx.doi.org/10.5703/1288284317367.

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This report presents, in detail, the development and implementation of a wireless solar powered DAQ system for continuous real-time monitoring of the Sagamore Parkway Bridge using the data collected from strain gauges installed in the bridge pier and its foundation piles. The data analysis showed that there is no significant change in the load-settlement response of the bridge pier 3 years after its construction. The pile cap contribution in carrying the total load carried by the bridge pier is significant (about 20%). The hourly ambient temperature trends match with the incremental bending moments measured on the bridge pier and the piles. The daily temperature cycles also affected the load transferred between the piles within the pile group. The water level fluctuations of the Wabash River impacted the total load carried by the pier, such that a rise in water level resulted in slight drop in the total load carried by the bridge pier due to buoyant forces. The overall results of the bridge monitoring showed that the bridge has performed well since its construction.
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10

Newton, Ronald, Joseph Riov, and John Cairney. Isolation and Functional Analysis of Drought-Induced Genes in Pinus. United States Department of Agriculture, September 1993. http://dx.doi.org/10.32747/1993.7568752.bard.

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Drought is a common factor limiting timber production in the U.S. and Israel. Loblolly (Pinus taeda) and alleppo pine (Pinus halepensis) seedling survival is reduced when out planted, and growth and reproduction are often hindered by periodic droughts during later stages of tree development. Molecular and gene responses to drought stress have not been characterized. The objectives were to characterize drought-induced gene clones from these pines, to determine the effects of a growth regulator on drought tolerance, ABA levels, and drought-induced gene expression in alleppo pine, and to develop procedures for loblolly pine transformation. Nearly 20 cDNA clones influenced by gradual, prolonged drought stress have been isolated. Many of these have been shown to be induced by drought stress, whereas several others are down-regulated. These are the first drought-induced genes isolated from a pine species. Two genomic clones (lp5-1 and lp3-1) have been sequenced and characterized, and each has been found to be associated with a gene family. Clone lp5 appears to code for a cell wall protein, and clone lp3 codes for a nuclear protein. The former may be associated with changing the elastic properties of the cell wall, while the latter may be involved in signal transduction and/or protection from desiccation in the nucleus. Clone lp3 is similar to a drought-induced gene from tomato and is regulated by ABA. Several DNA sequences that are specific to induction during growth-retardation in alleppo pine by uniconazole have been identified. The active DNA species is now being identified. Promoters from genomic clones, lp3 and lp5, have been sequenced. Both are functional when fused with the gus reporter gene and transferred to other plant tissues as well as responding to a simulated drought stress. Through exodeletion analysis, it has been established that the promoter ABRE element of lp3 responds to ABA and that drought-induction of lp3 expression may also involve ABA. Stable tobacco transformants carrying either the lp5 or the lp3 promoter fused to a reporter gus gene have been obtained. The lp5lgus fusion was expressed at several stages of tobacco development and differentiation including the reproductive stage. There was no difference in phenotype between the transformants and the wild type. Embryogenesis procedures were developed for slash pine, but attempts to couple this process with gene transfer and plantlet transformation were not successful. Transformation of pine using Agrobacterium appears tractable, but molecular data supporting stable integration of the Agrobacterium-transferred gene are still inconclusive.
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