Academic literature on the topic 'Forces occultes (Motion picture)'
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Journal articles on the topic "Forces occultes (Motion picture)"
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Schreiber, Christoph, Behnam Amiri, Johannes C. J. Heyn, Joachim O. Rädler, and Martin Falcke. "On the adhesion–velocity relation and length adaptation of motile cells on stepped fibronectin lanes." Proceedings of the National Academy of Sciences 118, no. 4 (January 22, 2021): e2009959118. http://dx.doi.org/10.1073/pnas.2009959118.
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The biphasic adhesion–velocity relation is a universal observation in mesenchymal cell motility. It has been explained by adhesion-promoted forces pushing the front and resisting motion at the rear. Yet, there is little quantitative understanding of how these forces control cell velocity. We study motion of MDA-MB-231 cells on microlanes with fields of alternating Fibronectin densities to address this topic and derive a mathematical model from the leading-edge force balance and the force-dependent polymerization rate. It reproduces quantitatively our measured adhesion–velocity relation and results with keratocytes, PtK1 cells, and CHO cells. Our results confirm that the force pushing the leading-edge membrane drives lamellipodial retrograde flow. Forces resisting motion originate along the whole cell length. All motion-related forces are controlled by adhesion and velocity, which allows motion, even with higher Fibronectin density at the rear than at the front. We find the pathway from Fibronectin density to adhesion structures to involve strong positive feedbacks. Suppressing myosin activity reduces the positive feedback. At transitions between different Fibronectin densities, steady motion is perturbed and leads to changes of cell length and front and rear velocity. Cells exhibit an intrinsic length set by adhesion strength, which, together with the length dynamics, suggests a spring-like front–rear interaction force. We provide a quantitative mechanistic picture of the adhesion–velocity relation and cell response to adhesion changes integrating force-dependent polymerization, retrograde flow, positive feedback from integrin to adhesion structures, and spring-like front–rear interaction.
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Smith, Jeffery A. "Hollywood Theology: The Commodification of Religion in Twentieth-Century Films." Religion and American Culture: A Journal of Interpretation 11, no. 2 (2001): 191–231. http://dx.doi.org/10.1525/rac.2001.11.2.191.
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A motion picture is a product formed by the intricate inter-play of film industry forces and cultural expectations. Hollywood must attract audiences and audiences crave gratification or, perhaps, edification. Movies with religious themes can deal with momentous issues, but take the risk of affronting deeply held beliefs. Problems naturally arise when matters as sensitive and speculative as the activity of the Creator and the role of the created become entertainment marketed to mass audiences. Technicolor scenery, special effects, celebrity actors, spiced-up scripts, and other big-screen production values may seem disrespectful or may divert attention away from serious reflection. Critics of consumer society have pointed to the manipulation, superficiality, and commercialization found in mass media environments and film scholars have evaluated movies with religious topics, but questions remain about cinematic treatments of ultimate meaning. The motion picture industry's customers have a multitude of spiritual perspectives.
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Wu, Shangqian, and Tianhui Zhang. "The Influence of Park Chung Hee’s Motion Picture Law on Korean Society." BCP Social Sciences & Humanities 21 (February 15, 2023): 602–7. http://dx.doi.org/10.54691/bcpssh.v21i.3647.
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The term ‘Korean wave’ is broadly defined as the huge achievement of South Korean cultural economy industries around the world. It represented a big milestone when South Korea’s movie “Parasite” won the Oscar for Best Picture, which was the first movie from non-English speaking country to win such award in the history. While lots of Korean filmmakers have been trying to produce their own flims for more than 100 years, the cinema of South Korea officially started in 1945 and have been strongly influenced by events and political forces. This paper mainly studies the content and influence of the Motion Picture Law (MPL) issued during Park Chung Hee era in the 1960s and later strict censorship and propaganda in 1970s under Park’s government control. It is worth exploring why the Korean film industry can achieve such achievements, and what role the MPL played in it. The experience and lessons are worthy of reference. This paper briefly reviews the development history of Korean film from a historical perspective, introduces the legal content and the historical background, and then discusses and analyzes its influence on the positive and negative sides at that time. Looking back at the twists and turns of the Korean movie industry is also of great significance to the development of other countries.
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Satheeshkumar, V. H., and P. K. Suresh. "Understanding Gravity: Some Extra-Dimensional Perspectives." ISRN Astronomy and Astrophysics 2011 (January 18, 2011): 1–10. http://dx.doi.org/10.5402/2011/131473.
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Gravity is one of the most inexplicable forces of nature, controlling everything, from the expansion of the Universe to the ebb and flow of ocean tides. The search for the laws of motion and gravitation began more than two thousand years ago but still we do not have the complete picture of it. In this paper, we have outlined how our understanding of gravity is changing drastically with time and how the previous explanations have shaped the most recent developments in the field like superstrings and braneworlds.
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Drake, Thomas G., Ronald L. Shreve, William E. Dietrich, Peter J. Whiting, and Luna B. Leopold. "Bedload transport of fine gravel observed by motion-picture photography." Journal of Fluid Mechanics 192 (July 1988): 193–217. http://dx.doi.org/10.1017/s0022112088001831.
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Motion pictures taken at Duck Creek, a clear stream 6.5 m wide and 35 cm deep near Pinedale, Wyoming, provide detailed, quantitative information on both the modes of motion of individual bedload particles and the collective motions of large numbers of them. Bed shear stress was approximately 6 Pa (60 dynes cm−2), which was about twice the threshold for movement of the 4 mm median diameter fine gravel bed material; and transport was almost entirely as bedload. The displacements of individual particles occurred mainly by rolling of the majority of the particles and saltation of the smallest ones, and rarely by brief sliding of large, angular ones. Entrainment was principally by rollover of the larger particles and liftoff of the smaller ones, and infrequently by ejection caused by impacts, whereas distrainment was primarily by diminution of fluid forces in the case of rolling particles and by collisions with larger bed particles in the case of saltating ones. The displacement times averaged about 0.2−0.4 s and generally were much shorter than the intervening repose times. The collective motions of the particles were characterized by frequent, brief, localized, random sweep-transport events of very high rates of entrainment and transport, which in the aggregate transported approximately 70% of the total load moved. These events occurred 9% of the time at any particular point of the bed, lasted 1–2 s, affected areas typically 20–50 cm long by 10–20 cm wide, and involved bedload concentrations approximately 10 times greater than background. The distances travelled during displacements averaged about 15 times the particle diameter. Despite the differences in their dominant modes of movement, the 8–16 mm particles typically travelled only about 30% slower during displacement than the 2–4 mm ones, whose speeds averaged 21 cm s−1. Particles starting from the same point not only moved intermittently downstream but also dispersed both longitudinally and transversely, with diffusivities of 4.6 and 0.26 cm2 s−1, respectively. The bedload transport rates measured from the films were consistent with those determined conventionally with a bedload sampler. The 2–4 mm particles were entrained 6 times faster on finer areas of the bed, where 8–16 mm particles covered 6% of the surface area, than on coarser ones, where they covered 12%, even though 2–4 and 4–8 mm particles covered practically the same percentage areas in both cases. The 4–8 and 8–16 mm particles, in contrast, were entrained at the same rates in both cases. To within the statistical uncertainty, the rates of distrainment balanced the rates of entrainment for all three sizes, and were approximately proportional to the corresponding concentrations of bedload.
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Bernitsas, M. M., and B. K. Kim. "Effect of Slow-Drift Loads on Nonlinear Dynamics of Spread Mooring Systems." Journal of Offshore Mechanics and Arctic Engineering 120, no. 4 (November 1, 1998): 201–11. http://dx.doi.org/10.1115/1.2829541.
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Spread mooring systems (SMS) may experience large-amplitude oscillations in the horizontal plane due to slow-drift loads. In the literature, this phenomenon is attributed to resonance. In this paper, it is shown that this conclusion is only partially correct. This phenomenon is investigated using nonlinear stability and bifurcation analyses which reveal an enhanced picture of the nonlinear dynamics of SMS. Catastrophe sets are developed in a parametric design space to define regions of qualitatively different system dynamics for autonomous SMS, including mean drift forces. Limited time simulations are performed to verify the qualitative conclusions drawn on the nonlinear dynamics of SMS using catastrophe sets. Slowly varying drift forces are studied as an additional excitation on the autonomous SMS and simulations reveal that slow drift may cause resonance or bifurcations with stabilizing or destabilizing morphogeneses. The mathematical model of SMS is based on the slow-motion maneuvering equations in the horizontal plane (surge, sway, yaw), including hydrodynamic forces with terms up to third-order, nonlinear restoring forces from mooring lines, and environmental loads due to current, wind, and wave-drift.
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Griffith, David A., Goksel Yalcinkaya, Gaia Rubera, and Verdiana Giannetti. "Understanding the Importance of the Length of Global Product Rollout: An Examination in the Motion Picture Industry." Journal of International Marketing 25, no. 4 (December 2017): 50–69. http://dx.doi.org/10.1509/jim.17.0044.
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Employing the resource-based view of the firm and the competitive forces perspective, the authors examine how brand equity (star power, director power, and brand extensions), financial resources, and competitive intensity serve both as antecedents to the length of global product rollout and as moderators of the effect of length of global product rollout on global product performance. The results, based on data from the motion picture industry, demonstrate that brand equity, financial resources, and competitive intensity result in shorter global product rollout and that shorter global product rollout enhances global product performance. They also find that brand equity and financial resources operate as moderators, magnifying the effect of length of global product rollout on global product performance. Implications for international marketing academics and practitioners are presented.
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Bini, Donato, Paolo Carini, and Robert T. Jantzen. "The Intrinsic Derivative and Centrifugal Forces in General Relativity: I." International Journal of Modern Physics D 06, no. 01 (February 1997): 1–38. http://dx.doi.org/10.1142/s0218271897000029.
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Everyday experience with centrifugal forces has always guided thinking on the close relationship between gravitational forces and accelerated systems of reference. Once spatial gravitational forces and accelerations are introduced into general relativity through a splitting of spacetime into space-plus-time associated with a family of test observers, one may further split the local rest space of those observers with respect to the direction of relative motion of a test particle world line in order to define longitudinal and transverse accelerations as well. The intrinsic covariant derivative (induced connection) along such a world line is the appropriate mathematical tool to analyze this problem, and by modifying this operator to correspond to the observer measurements, one understands more clearly the work of Abramowicz et al. who derine an "optical centrifugal force" in static axisymmetric spacetimes and attempt to generalize it and other inertial forces to arbitrary spacetimes. In a companion article the application of this framework to some familiar stationary axisymmetric spacetimes helps give a more intuitive picture of their rotational features including spin precession effects, and puts related work of de Felice and others on circular orbits in black hole spacetimes into a more general context.
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Guslienko, Konstantin. "Magnetic Vortex Core String Gyrotropic Oscillations in Thick Cylindrical Dots." Magnetism 2, no. 3 (July 19, 2022): 239–50. http://dx.doi.org/10.3390/magnetism2030018.
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The nonuniform magnetic vortex gyrotropic oscillations along the cylindrical dot thickness were calculated. A generalized Thiele equation was used for describing the vortex core motion including magnetostatic and exchange forces. The magnetostatic interaction was accounted for in a local form. This allowed reducing the Thiele equation of motion to the Schrödinger differential equation and analytically determining the spin eigenmode spatial profiles and eigenfrequencies using the Liouville–Green method for the high-frequency modes. The mapping of the Schrödinger equation to the Mathieu equation was used for the low-frequency gyrotropic mode. The lowest-frequency gyrotropic mode transformed to the dot faces localized mode, increasing the dot thickness. The vortex gyrotropic modes are described for a wide range of the dot thicknesses according to the concept of the turning points in the magnetostatic potential. This approach allows treating the vortex localized modes (turning points) and nonlocalized modes within a unified picture.
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Maslova, A. I., A. V. Pirozhenko, and O. O. Pirozhenko. "Effect of the solar radiation pressure on the motion of satellites in almost circular Earth orbits." Technical mechanics 2024, no. 2 (July 4, 2024): 41–54. http://dx.doi.org/10.15407/itm2024.02.041.
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This paper considers the effect of the solar radiation pressure on the motion of a satellite in an almostcircular low-Earth orbit. The formulation of the problem is due to the need to determine the effect of solar radiation pressure forces on the motion of light commercial Earth remote sensing (ERS) satellites with large surface areas (solar batteries and antennas). The goal is to determine the main regularities of this effect, construct reasonably simple and accurate estimates of changes in orbital parameters for the orbits under consideration, and clarify their physics (cause-and-effect relations) The novelty of this study also lies in the use of variables specially introduced to describe a motion in almost circular orbits. The study assumes that the solar radiation pressure force is constant throughout the entire orbit, and it is concerned with dawn-dusk orbits, which are often used for ERS satellites with radar observation systems. The paper presents simple analytical expressions that describe the main regularities of short-term (several days) changes in orbital parameters. It is shown that the change in the orientation of the orbital plane is determined by the action of the gyroscopic moment. This moment balances the effect of the moment of external forces aimed at changing the orientation and the change in the orientation perpendicular to the direction of the applied moment of the external forces. The main effect of the solar radiation pressure is the excitation of forced oscillations of the orbital radius, whose amplitude linearly increases with time. The maximums of these oscillations (apogee) are at the point where the light pressure forces maximally slow down the motion of the satellite (directed oppositely to the velocity), and the minimums (perigee) are at the point of the maximum motion acceleration. It is shown that the annual movement of the Sun can qualitatively change the picture of the evolution of orbital parameters. For sun-synchronous dawn-dusk orbits, compact analytical solutions for changes in orbital parameters are constructed, and it is shown that the annual movement of the Sun’s declination reverses the direction of evolution of the orbital shape. The calculations showed a reasonably high accuracy of the analytical solutions at the initial stage. The obtained numerical estimates make it possible to evaluate the effect of the solar pressure on changes in orbital parameters.
Books on the topic "Forces occultes (Motion picture)"
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Coy, Jean-Louis. Forces occultes: Le complot judéo-maçonnique au cinéma : le livre, le film (DVD) dans le bonus : un entretien avec Jean-Robert Ragache. Paris: Véga, 2008.
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Smith, Starr. Jimmy Stewart: Bomber pilot. St. Paul, MN: Zenith Press, 2005.
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Antonia, Felix, ed. Windtalkers: A John Woo film. New York: Newmarket Press, 2002.
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Dang dai dian ying xin shi li: Yazhou xin dian ying da shi yan jiu = The new forces of contemporary cinema : the study on masters of new Asian cinema. Beijing Shi: Beijing da xue chu ban she = Peking University Press, 2014.
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"Ivan's Childhood" by Andrei Tarkovsky. Intellect, Limited, 2022.
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(Editor), Antonia Felix, Jeff Bingaman (Introduction), and Stephen Vaughan (Photographer), eds. Windtalkers: The Making of the John Woo Film about the Navajo Code Talkers of World War II (Newmarket Pictorial Movebooks). Newmarket Press, 2002.
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Smith, Starr. Jimmy Stewart: Bomber Pilot. Zenith Press, 2006.
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Min guo cong shu. Shanghai shu dian, 1989.
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Succi, Sauro. LBE for Generalized Hydrodynamics. Oxford University Press, 2018. http://dx.doi.org/10.1093/oso/9780199592357.003.0025.
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This chapter presents the main techniques to incorporate the effects of external and/or internal forces within the LB formalism. This is a very important task, for it permits us to access a wide body of generalized hydrodynamic applications whereby fluid motion couples to a variety of additional physical aspects, such as gravitational and electric fields, potential energy interactions, chemical reactions and many others. It should be emphasized that while hosting a broader and richer phenomenology than “plain” hydrodynamics, generalized hydrodynamics still fits the hydrodynamic picture of weak departure from suitably generalized local equilibria. This class is all but an academic curiosity; for instance, it is central to the fast-growing science of Soft Matter, a scientific discipline which has received an impressive boost in the past decades, under the drive of micro- and nanotechnological developments and major strides in biology and life sciences at large.
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Billheimer, John. Hitchcock and the Censors. University Press of Kentucky, 2019. http://dx.doi.org/10.5810/kentucky/9780813177427.001.0001.
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The Motion Picture Production Code controlled the content and final cut on all films made and distributed in the US from 1934 to 1968. Code officials protected sensitive ears from the standard four-letter words as well as a few five-letter words like tramp and six-letter words like cripes. They also scrubbed ‘excessively lustful’ kissing from the screen, and ensured that no criminal went unpunished. Censors demanded an average of twenty changes, ranging from trivial to mind-boggling, on each of Alfred Hitchcock’s films during his most productive years. No production escaped these changes, which rarely improved the finished film. Code reviewers dictated the ending of’ Rebecca, shortened the shower scene in’ Psycho, absolved Cary Grant of guilt in’ Suspicion, edited Cole Porter’s lyrics in’ Stage Fright, and decided which shades should be drawn in’ Rear Window. Nevertheless, Hitchcock still managed to push the boundaries of sex and violence permitted in films by charming (and occasionally tricking) the censors and by swapping off bits of dialogue, plot points, and individual shots (some of which had been deliberately inserted as trading chips) to protect cherished scenes and images. The director’s priorities in dealing with the censors highlight both his theories of suspense and the single-mindedness of Code officials. Hitchcock and the Censors’ traces the forces that led to the Production Code and describes Hitchcock’s interactions with Code officials on a film-by-film basis as he fought to protect his creations, bargaining with Code reviewers and sidestepping censorship to produce a lifetime of memorable films.
Book chapters on the topic "Forces occultes (Motion picture)"
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Zubairy, M. Suhail. "Newtonian mechanics and the deterministic world." In A Mysterious Universe, 7–14. Oxford University PressOxford, 2023. http://dx.doi.org/10.1093/oso/9780198883067.003.0002.
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Abstract After briefly discussing the contributions of Copernicus, Kepler, and Galileo, the main contributions of Newton are presented. His major contributions, including the law of gravitation and the laws of motion, initiated the modern age of science. Newtonian laws painted a deterministic picture of the universe—if the location of all the objects in the universe and the forces acting upon them at a given time are known then the future can be predicted precisely. Newton’s views on space and time are also presented. Most of these ideas were challenged by the modern theories of nature, namely the special and general theories of relativity and quantum mechanics.
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Jackson, Robert H. "That Man As Economist." In That Man, 119–34. Oxford University PressNew York, NY, 2003. http://dx.doi.org/10.1093/oso/9780195168266.003.0007.
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Abstract Many of The Litigations and other matters that presented legal aspects were also economic matters. It always seemed to me that the President was at his weakest in dealing with economic or business problems. He had not engaged in business as my law practice had compelled me to do, and he had no personal knowledge of its methods or its problems. He tended to think of economic matters as personal rather than impersonal forces. He was much inclined to think about economic matters in terms of rights and wrongs. He was inclined to think that we were prosecuting a group of businessmen because they had done some moral wrong, and that if he talked to them and made them see that their course was morally wrong, they would do something about it. When we were considering the commencement of Department of Justice actions in 1937 to dissolve the motion picture combines, I went to the President and told him that I wanted to start an action against them. The President said, “Well now, of course, they’ve been doing wrong, but do you really need to sue these men? If you would bring them in here and let me talk with those fellows, don’t you think they would change their practices? I think they can be straightened out.” My answer, of course, was that these men were in a sense victims of their practices as well as perpetrators of them. It was a system that had grown up to where no one man or group could break it up without the intervention of government. Even if they all decided they ought to break it up, they could not do it. It was not a moral problem. It was not a right and wrong problem. It was a social and antisocial problem that did not reach moral concepts. What the President found difficult to envision was that they were caught up in a course of business practices that they were as powerless to escape from individually as if they were prisoners.
Conference papers on the topic "Forces occultes (Motion picture)"
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Baines, Nicholas C. "Flow Development in Radial Turbine Rotors." In ASME 1996 International Gas Turbine and Aeroengine Congress and Exhibition. American Society of Mechanical Engineers, 1996. http://dx.doi.org/10.1115/96-gt-065.
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This paper surveys the development of the primary and secondary flows in the rotors of radial-inflow turbines. Information previously scattered throughout the literature has been brought together, and it has been possible to create a coherent picture and a good understanding of the complex flow processes which occur. The secondary flow is generated by cross-passage forces due to the turning of the blades, and Coriolis forces. Near the leading edge these give rise to a strong vortex adjacent to the pressure surface, moving low momentum fluid from hub to tip. This feature helps to explain why best efficiency occurs typically at 20°–30° negative incidence. Attempts to correlate the optimum incidence angle using traditional slip factor expressions can give quite misleading results, but a new approach based on the blade loading shows considerable promise. Nearer the exit there is motion of fluid from hub to tip near the suction surface and a vortex in the suction surface-shroud corner, and this is linked to the highly non-uniform flow at exit. The latter effect makes the prediction and correlation of rotor deviation information very difficult, despite the development of a rational exit averaging procedure. The present deviation data are sparse and not easy to correlate.
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Soni, Prashant K., and Carl M. Larsen. "Vortex Pattern Comparison for Periodic and Harmonic Combined Cross-Flow and In-Line Forced Oscillations." In ASME 2009 28th International Conference on Ocean, Offshore and Arctic Engineering. ASMEDC, 2009. http://dx.doi.org/10.1115/omae2009-80089.
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For prediction of vortex-induced vibrations (VIV) the empirical models apply hydrodynamic coefficients to represent the fluid forces on the slender structures. The coefficients are in most cases found by measuring forces on a rigid cylinder under harmonic pure in-line (IL) or pure cross-flow (CF) forced motions, and are generally presented as functions of non-dimensional motion amplitude and frequency. The objective of the present work has been to find hydrodynamic coefficients for realistic combinations of CF and IL motions. Such trajectories were found from measured VIV of a flexible beam, and then used as forced motions of a rigid cylinder in uniform flow. Hydrodynamic forces were measured and used for calculation of hydrodynamic coefficients. The diameter of the rigid cylinder was larger than for the flexible beam in order to obtain optimum conditions for both experiments. However, both Reynolds number and non-dimensional frequency were identical for the two test types. The flexible beam oscillations were not perfectly periodic, but close to. More than one periodic trajectory could hence be identified as representative for the observed response, and these were used as forced motions in order to study the variability of the hydrodynamic coefficients. Alternative harmonic loops were also constructed in order to investigate the potential for using coefficients from harmonic tests as basis for empirical models. The vortex shedding process behind the cylinder has been mapped using Particle Image Velocimetry (PIV). PIV planes can picture the difference in cylinder wake for these trajectories and thus help to understand the process. The vorticity patterns at instantaneous positions for both periodic and harmonic trajectories are obtained. The vortices were mapped and the forces were measured simultaneously. Higher order harmonic components of the force are seen for all types of trajectories, and a correlation between these components and the vortex shedding pattern is observed.
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Song, Xue Guan, Lei Cui, and Young Chul Park. "Three-Dimensional CFD Analysis of a Spring-Loaded Pressure Safety Valve From Opening to Re-Closure." In ASME 2010 Pressure Vessels and Piping Division/K-PVP Conference. ASMEDC, 2010. http://dx.doi.org/10.1115/pvp2010-25024.
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We describe the dynamic analysis of a spring-loaded pressure safety valve (PSV) using a moving mesh technique and transient analysis in computational fluid dynamics (CFD). Multiple domains containing pure structural meshes are generated to ensure that the correlative mesh could change properly without negative volumes. With a geometrically accurate CFD model including the PSV and vessel rather than only the PSV, the entire process from valve opening to valve re-closure is presented. A detailed picture of the compressible fluid flowing through the PSV is obtained, including flow features in the very small seat region. In addition, the forces on the disc and its motion are monitored. Results from the model were very useful in investigating the dynamic and fluid characteristics of the PSV. Our practical CFD model has the potential to reduce the costs and risks associated with the development of new pressure safety valve designs. Future work will focus on improving the spring stiffness and seat region to eliminate or reduce vibration during the re-closure process.
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Carcasci, Cosimo, Marco Sacco, Marco Landucci, and Marco Fiaschi. "From Piping Deformation to Pressure Pulsation Measurements to Solve LDPE Plants Vibration Issues." In ASME 2018 Pressure Vessels and Piping Conference. American Society of Mechanical Engineers, 2018. http://dx.doi.org/10.1115/pvp2018-84666.
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Damages and failures in industrial plants are often related to vibration issues. Reciprocating compressors are typically affected by vibration phenomena due to the very nature of reciprocating motion as alternating forces and pressure pulsations are direct and inevitable consequences of reciprocation. Many preventive technical measures are undertaken in the detailed engineering design to avoid high levels of vibration, e.g. properly designed foundations, mass balancing, volume bottles, restriction orifices and piping supports. Nevertheless, vibration problems may still arise after a machine is installed in a plant and is started up, and often the vibration is not the result of a poor detailed design of the compressor itself but may depends on the piping and supports layout in the plant. Considering the extremely high pressures involved in the LDPE process (discharge pressure is generally between 160 and 350 Mpa), especially in tubular reactor plants, safety is a key consideration, and avoiding vibrations and consequential piping ruptures is essential for optimal and safe plant operation. In a tubular reactor polyethylene plant, high piping vibrations were present on the Hypercompressor piping from the first machine start-up. Despite immediate analysis and small modifications to a few pipe supports, some areas continued to be subject to this phenomenon, potentially leading to ruptures, welding failures and hazardous gas leakages. Therefore, the end user decided to involve an independent third party consultant. During the site survey, the piping system was fully analysed to investigate the nature and the causes of the high vibrations, and it was decided that both vibration and pulsation measurements had to be performed, to obtain a complete and realistic picture of the phenomenon. While vibration measurement could be performed as a standard procedure on this kind of machine, pulsation measurement was a challenging operation since dynamic pressure transducers could not be used at such high pressures (above 100 MPa). Thus, an experimental technique was used. The pulsation measurements were performed using strain gage sensors that dynamically detected the circumferential deformation of the pipes. Information about the internal pressure was derived from the pipe deformation through the well-known theory of cylinders under internal pressure and in this way the pulsation measurements could be compared to the acoustical analysis performed during the detailed engineering phase. The analysis highlighted acoustic resonances that were not present in the project analysis, mainly due to an incorrect evaluation of the thermodynamic properties of ethylene gas, which changes significantly when the gas is subject to the high pressures at which the Hypercompressor works. Moreover, the vibration measurements were compared to the pulsations at some key points and to the mechanical natural frequency of the relevant piping segment, identifying also areas subject to mechanical resonance. After understanding the root cause of these vibrations, effective and low-impact countermeasures were recommended and implemented in a few key points, leading to a drastic reduction of the vibrations, below the limit values recommended by the standards.