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Journal articles on the topic 'Vibrational analysis'

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Author: Grafiati

Published: 4 June 2021

Last updated: 31 January 2023

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1

Lian, Jijian, Yan Zheng, Chao Liang, and Bin Ma. "Analysis for the Vibration Mechanism of the Spillway Guide Wall Considering the Associated-Forced Coupled Vibration." Applied Sciences 9, no. 12 (June 25, 2019): 2572. http://dx.doi.org/10.3390/app9122572.

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During the flood discharge in large-scale hydraulic engineering projects, intense flow-induced vibrations may occur in hydraulic gates, gate piers, spillway guide walls, etc. Furthermore, the vibration mechanism is complicated. For the spillway guide wall, existing studies on the vibration mechanism usually focus on the vibrations caused by flow excitations, without considering the influence of dam vibration. According to prototype tests, the vibrations of the spillway guide wall and the dam show synchronization. Thus, this paper presents a new vibration mechanism of associated-forced coupled vibration (AFCV) for the spillway guide wall to investigate the dynamic responses and reveal coupled vibrational properties and vibrational correlations. Different from conventional flow-induced vibration theory, this paper considers the spillway guide wall as a lightweight accessory structure connected to a large-scale primary structure. A corresponding simplified theoretical model for the AFCV system is established, with theoretical derivations given. Then, several vibrational signals measured in different structures in prototype tests are handled by the cross-wavelet transform (XWS) to reveal the vibrational correlation between the spillway guide wall and the dam. Afterwards, mutual analyses of numeral simulation, theoretical derivation, and prototype data are employed to clarify the vibration mechanism of a spillway guide wall. The proposed mechanism can give more reasonable and accurate results regarding the dynamic response and amplitude coefficient of the guide wall. Moreover, by changing the parameters in the theoretical model through practical measures, the proposed vibration mechanism can provide benefits to vibration control and structural design.

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2

Qin, Zhu, Cao, Jiang, Gu, Wang, and Zhang. "Computational Analysis of Exotic Molecular and Atomic Vibrations in Ice XV." Molecules 24, no. 17 (August 27, 2019): 3115. http://dx.doi.org/10.3390/molecules24173115.

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It is always difficult to assign the peaks of a vibrational spectrum in the far-infrared region. The two distinct peaks seen in many ice phases are still a mystery to date. The normal modes of ice XV were calculated using the CASTEP code based on first-principles density functional theory. On the basis of vibrational modes analysis, we divided the translational modes into three categories: four-bond vibrations, which have the highest energy levels; two-bond vibrations, which have medium levels of energy; and relative vibrations between two sublattices, which have the lowest energy. Whale et al. found that some intramolecular stretching modes include the isolated vibration of only one O–H bond, whereas the others do not vibrate in ice XV. We verified this phenomenon in this study and attributed it to local tetrahedral deformation. Analysis of normal modes, especially in the translation and stretching band of ice XV, clarified the physical insights of the vibrational spectrum and can be used with other ice phases.

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3

Stephen, R. O., and Leonard D. M. Nokes. "Vibrational analysis." Journal of Biomedical Engineering 7, no. 4 (October 1985): 341–42. http://dx.doi.org/10.1016/0141-5425(85)90068-8.

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4

Jiang, Li, Zhenyue Ma, Jianwei Zhang, Mohd Yawar Ali Khan, Mengran Cheng, and Libin Wang. "Chaotic Characteristic Analysis of Vibration Response of Pumping Station Pipeline Using Improved Variational Mode Decomposition Method." Applied Sciences 11, no. 19 (September 23, 2021): 8864. http://dx.doi.org/10.3390/app11198864.

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The measured vibrational responses of the pumping station pipeline in the irrigation site were chosen to confirm the chaotic characteristics of the pumping station pipeline vibration and to determine the vibrational excitation that makes it chaotic. First, the chaotic properties of the pipeline vibration responses were investigated using a saturation correlation dimension and the maximum Lyapunov exponent. The vibration excitation with chaotic features was obtained using an improved variational mode decomposition (IVMD) method to examine the multi-time-scale chaotic characteristics of the pipeline vibration responses. The results show that the vibrational responses of each measuring point of the pipeline under different operating conditions have clear chaotic characteristics, where the chaotic characteristics of the axial points and bifurcated pipe points are relatively strong. The vibration of the operating conditions and measurement points affected by the unit’s operation and flow state change is further complicated. The intrinsic mode function (IMF) produces a low-dimensional chaotic attractor after the IVMD disrupts the vibration response. Still, the vibration excitation of the remaining components on behalf of the units does not have chaotic properties, implying that water pulsation excitation makes the pumping station pipeline vibrations chaotic. The vibration excitation caused by the unit’s operation covers the chaotic characteristics of the pipeline vibration and increases its uncertainty. The outcomes of this study provide a theoretical basis for further exploration of the vibration characteristics of pumping station pipelines, and a new method of chaos analysis is proposed.

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5

Zhang, Rong Hai, Ning Yuan Zhu, and Gai Pin Cai. "Surface Effect Mechanism Analysis for Vibrational Rotary Forging." Advanced Materials Research 314-316 (August 2011): 753–58. http://dx.doi.org/10.4028/www.scientific.net/amr.314-316.753.

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As a contact of vibrational rotary forging is highly nonlinear, the contact area and boundary between rotary toolhead and workpiece had more accurate calculation, made the contact boundary more tally with the actual situation. For a surface effect is of complexity for vibrational rotary forging, a vibrational rotary forging visco-elasticity plasticity model was built, and the visco-elasticity spatial matrix and the visco-plasticity spatial matrix were derived by the generalized Hooke's law in elasticity theory and the increase theory in mechanics of plasticity, then by the finite element founction of MATLAB for the surface effect analyzed during the vibrational rotary forging deformation, it is shown as blow: the surface effect should be appeared with high frequency vibration or low frequency vibration, but there are some conditions for surface effect produced during plastic process, and then the hypothesis that the friction vector is reversal of deformation load, and it is benefit to deformation process during the part of time in vibration period is validated.

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6

Mrozek, Piotr, Ewa Mrozek, and Andrzej Werner. "Electronic Speckle Pattern Interferometry for Vibrational Analysis of Cutting Tools." Acta Mechanica et Automatica 12, no. 2 (June 1, 2018): 135–40. http://dx.doi.org/10.2478/ama-2018-0021.

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Abstract A Michelson interferometer based ESPI system for static and vibration out of plane displacement measurements is presented. The aim of the article is to demonstrate the usability of ESPI non-contact measurement method in the field of machining. The correlation fringe patterns were visualized using custom software. The accuracy of ESPI interferometer was verified by the comparison with measurement results collected using industrial XL-80 laser system. The efficacy in vibration analysis was tested by studying the mode shapes and resonant frequencies of the transverse vibrations of square plates. The measurement methodology was used to determine natural frequencies and the shapes of vibrational modes of NFTe 100x1.2/64-II circular slitting saw. As a result the values of rotational speed that should be avoided during machining were determined.

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7

Selim, Mahmoud M., and Taher A. Nofal. "Vibrational analysis of nanoplate with surface irregularity via Kirchhoff plate theory." Nanomaterials and Nanotechnology 11 (January 1, 2021): 184798042110011. http://dx.doi.org/10.1177/18479804211001148.

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In this work, an attempt is done to apply the Kirchhoff plate theory to find out the vibrational analyses of a nanoplate incorporating surface irregularity effects. The effects of surface irregularity on natural frequency of vibration of nanomaterials, especially for nanoplates, have not been investigated before, and most of the previous research have been carried for regular nanoplates. Therefore, it must be emphasized that the vibrations of irregular nanoplate are novel and applicable for the nanodevices, in which nanoplates act as the main structure of the nanocomposite. The surface irregularity is assumed in the parabolic form at the surface of the nanoplate. A novel equation of motion and frequency equation is derived. The obtained results provide a better representation of the vibration behavior of irregular nanoplates. It has been observed that the presence of surface irregularity affects considerably on the natural frequency of vibrational nanoplates. In addition, it has been seen that the natural frequency of nanoplate decreases with the increase of surface irregularity parameter. Finally, it can be said, the present results may serve as useful references for designing oscillators and nanoscale devices, in which nanoplates act as a structural component for most prevalent nanocomposites structural element.

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8

Darbha, K., S. Ling, and A. Dasgupta. "Stress Analysis of Surface-Mount Interconnections Due to Vibrational Loading." Journal of Electronic Packaging 119, no. 3 (September 1, 1997): 183–88. http://dx.doi.org/10.1115/1.2792232.

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Recently, accelerated testing of surface mount interconnects under combined temperature and vibration environments has been recognized to be a necessary activity to ensure enhanced test-time compression. Successful use of vibration stresses requires a clear understanding of the correlation between vibrational damage and thermomechanical damage in surface mount solder joints. Hence, fatigue due to vibrational loading is important and accurate quantitative models are required to model effects due to vibrational fatigue. The proposed analysis in this paper contributes towards development of such quantitative models. This paper presents an approximate method to analyze stresses in surface mount solder joints subjected to vibration loading, using a generalized multidomain Rayleigh-Ritz approach (Ling and Dasgupta, 1995). The advantage of this approach is in its computational efficiency, compared to general-purpose finite element methods. Ling developed this approach in the context of thermomechanical stress analysis of solder joints. In this paper, the technique is modified and adapted for analyzing stresses caused by out-of-plane flexural dynamic modes of the printed wiring boards (PWBs). The analysis uses a two-step procedure where the local PWB curvatures are first estimated and the resulting deformations in the solder interconnect are then determined. The input boundary conditions for the first step are the bending moments in the PWB due to random vibrations. The stiffness of the interconnect assembly is then predicted using an energy method and curved-beam analysis. The bending moment and the computed stiffness of the interconnect assembly are then used to predict the local curvature of the PWB under any given surface-mount component by using an eigenfunction technique developed by Suhir (Suhir, 1988). In the second step of the analysis, the local curvature of the PWB is used as a boundary condition to predict the state of deformations, stresses, and strains in the solder joint using a modified version of the multidomain Rayleigh-Ritz approach. The overall method is applied to a specific example (J-lead solder joint) for illustrative purposes, and compared to finite element predictions for validation.

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9

Posada-Amarillas, Alvaro, and Ignacio L. Garzón. "Vibrational analysis ofNinclusters." Physical Review B 54, no. 15 (October 15, 1996): 10362–65. http://dx.doi.org/10.1103/physrevb.54.10362.

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10

Vinoth Kumar, K., T. G. Loganathan, A. Bharath, B. Shyam Sundar, and K. K. Abishek. "Comparative structural vibration analysis of machinery and GFRP with Al7075." MATEC Web of Conferences 144 (2018): 01009. http://dx.doi.org/10.1051/matecconf/201814401009.

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The current scenario of the industries is that the major losses in efficiency of a machine are due to vibration and friction. To reduce the detrimental effects of vibration we need to decrease the frequency and amplitude of vibration or completely eliminate vibration. To do that one must quantify vibration that already occurs in machinery and structural components. Which is the aim of this paper. The intention of the paper is to obtain and characterize the vibration signature of equipment used in a company and composite material. We have designed a setup to vibrational properties composites, vibrational signature of industrial equipment .To study vibration properties, micro-electrical mechanical systems (MEMS) based accelerometers are used to measure acceleration of the material about the datum when displaced. The data obtained is processed in MATLAB using ARDUINO relayed to computer to convert the data to frequency spectra using Fast-Fourier transforms (FFT). We ultimately compared the vibrational properties of two lathes used at a metal fabrication plant operating at different Conditions and quantified the vibration results using Fast Fourier Transforms (FFT) algorithm. The vibration signatures of a composite is studied along with which various properties like Damping Coefficient, Free Vibration, GFRP, Natural Frequency applications are studied.

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11

Sobolev, Vladimir I., and Tatiana N. Chernigovskaya. "Research into the dynamics of radio telescope foundationsusing laser vibration measuring equipment." Journal «Izvestiya vuzov. Investitsiyi. Stroyitelstvo. Nedvizhimost» 10, no. 3 (2020): 420–27. http://dx.doi.org/10.21285/2227-2917-2020-3-420-427.

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This study presents a technology for determining the dynamic parameters of the foundation structures of radio telescopes by a non-contact method based on the use of laser vibration measuring equipment. The main results of a dynamic process analysis are described. The research was carried out in the form of microdynamic tests of foundation structures with the determination of natural oscillation periods based on lower vibrational forms. Measurements of natural vibrations of radio telescope foundations under applied shock were performed, followed by spectral mapping of vibrational processes. The tests were carried out using a tachometric laser vibrometer RSV-150 included in the register of vibration measuring equipment in Russia. Spectral mappings were obtained using Fourier transforms implemented in software packages of the hardware developers. The dynamic features of radio tele-scope foundations are formalized in the form of spectral maps of the initial records of vibrational proc-esses. The method of microdynamic tests using a vibration meter is presented, along with the principles of its operation and the sequence of numerical processing of records of dynamic processes imple-mented on a personal computer using frequency displays of natural vibrations of structures. The values of natural vibration frequencies obtained as a result of measurements confirmed the rigidity and integ-rity of foundation piles. Pronounced solitary peaks of natural vibration frequencies point to the form of natural vibrations of structures as single-mass systems with the absence of deformational forms of vi-brations in the foundation body.

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12

Berardi, Umberto, and Gino Iannace. "Additive manufacturing for minimizing vibration damages in the water-stop tray of washing machines." Journal of Low Frequency Noise, Vibration and Active Control 36, no. 2 (June 2017): 193–99. http://dx.doi.org/10.1177/0263092317712017.

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The present work aims to study the water-stop tray, a front-loading component of a washing machine. As most of the components of washing machines, the water-stop tray suffers significant vibrations especially when the spin speed increases. A vibrational analysis of the current typical design was realized. Then, four modified trays were investigated and a hammer impulse response was recorded using 13 accelerometers in order to measure the frequency response of each tray. The results allow to identify the key parameters that affect the vibrational response of a water-stop tray. Finally, the comparative analysis among the different designs allows to select the tray with the lowest vibration amplitude.

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13

Fuzaro de Almeida, Estevão, Fábio Roberto Chavarette, and Douglas da Costa Ferreira. "POTÊNCIA GERADA EM UM SISTEMA DINÂMICO DECAPTAÇÃO DE ENERGIA CONTROLADO VIA MÉTODO LQR: COMPARAÇÃO ENTRE EXCITAÇÃO PERIÓDICA E NÃO-IDEAL." COLLOQUIUM EXACTARUM 12, no. 2 (September 20, 2020): 62–76. http://dx.doi.org/10.5747/ce.2020.v12.n2.e319.

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Most of active control in vibrational dynamic systems is used to reduce vibrations. However,the aim of this research is specifically the use of vibrations to generate electrical energy, in such a way that the vibration becomes a desired phenomenon. In this way, the intention is to use the Optimal Control via Linear Quadratic Regulator (LQR), resulting in greater transduction of vibrational energy to electric power, varying the excitation type and performing an analysis of the stabilityand the effects of control to the dynamic system.The analyzed system is a bimodal mass-spring-damper with piezoelectric coupling-mechanic who suffers excitations periodic and non-ideal. This work intends to determine which system generates more electric power.

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14

Sugakov, V. I. "Fine structure of thermoluminescence assisted by molecular vibrations in disordered organic semiconductors." Journal of Physics: Condensed Matter 34, no. 18 (March 2, 2022): 185703. http://dx.doi.org/10.1088/1361-648x/ac50d9.

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Abstract The article deals with the issue of the influence of a separate mode of molecular vibrations on the formation of the thermoluminescence from disordered systems with quasi-continuous spectra of localized carriers. The contribution of vibrations is noticeable if the energy of their quanta is close to the depth of some localized carriers and the transition of the carrier into the conductive region occurs via absorption of these quanta. At some value of a carrier–vibration interaction, the effect manifests itself in the appearance of a fine discrete structure on the generally smooth thermoluminescence curve. The thermoluminescence of polymers is calculated using the model of non-adiabatic transitions, in which the carrier–vibrational interaction is determined by the displacements of nuclei in the presence of the carrier. The dependence of the arising discrete structure of the thermoluminescence curve on a number of parameters of the system like the magnitude of the carrier–vibration interaction, the width of vibrational levels, the parameters of the conductive region is investigated. The processes with participation of multiple quanta of vibrations are investigated and the formation of repetitive structures on the thermoluminescence curve has been shown owing to the absorption of several vibrational quanta. Analysis of a number of experiments is presented using the suggested theory.

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15

Cai, Gai Pin, Ning Yuan Zhu, and Na Wen. "Stress Analysis of Sheet Metal Vibration Incremental Forming." Advanced Materials Research 154-155 (October 2010): 166–70. http://dx.doi.org/10.4028/www.scientific.net/amr.154-155.166.

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As a non-homogenous force stresses during incremental forming, sheet metal easily tended to instability, and some defects, such as deposition, wrinkle and fracture, would appear. If the vibration technique was combined the incremental forming process, its deformation mechanism would be different from that of the old process, and sheet metal deformation quality was also risen. Then some mechanical equations were built by force analyzed on element in local contact zone of die head forcing down. According to reasonable hypothesis and simplified, the equations were solved. Some stress-time curves of the element were obtained by given process parameters, vibrational parameters and time parameters. It is shown from analysis that stress variety of the element is closely related to amplitude, frequency and forming angle, effect of sheet metal vibration incremental forming with high frequency vibration is more superior than that of with low frequency vibration; only when vibrational parameters are reasonably matching technical parameters, the effective vibration incremental forming can be obtained.

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16

Verma, Niraj, Yunwen Tao, Wenli Zou, Xia Chen, Xin Chen, Marek Freindorf, and Elfi Kraka. "A Critical Evaluation of Vibrational Stark Effect (VSE) Probes with the Local Vibrational Mode Theory." Sensors 20, no. 8 (April 21, 2020): 2358. http://dx.doi.org/10.3390/s20082358.

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Over the past two decades, the vibrational Stark effect has become an important tool to measure and analyze the in situ electric field strength in various chemical environments with infrared spectroscopy. The underlying assumption of this effect is that the normal stretching mode of a target bond such as CO or CN of a reporter molecule (termed vibrational Stark effect probe) is localized and free from mass-coupling from other internal coordinates, so that its frequency shift directly reflects the influence of the vicinal electric field. However, the validity of this essential assumption has never been assessed. Given the fact that normal modes are generally delocalized because of mass-coupling, this analysis was overdue. Therefore, we carried out a comprehensive evaluation of 68 vibrational Stark effect probes and candidates to quantify the degree to which their target normal vibration of probe bond stretching is decoupled from local vibrations driven by other internal coordinates. The unique tool we used is the local mode analysis originally introduced by Konkoli and Cremer, in particular the decomposition of normal modes into local mode contributions. Based on our results, we recommend 31 polyatomic molecules with localized target bonds as ideal vibrational Stark effect probe candidates.

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17

Alişverişçi, G. Füsun. "The Nonlinear Analysis of Vibrational Conveyers with Non-Ideal Crank-and-Rod Exciters." Applied Mechanics and Materials 706 (December 2014): 44–53. http://dx.doi.org/10.4028/www.scientific.net/amm.706.44.

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With the crank-and-rod exciters, the vibrational conveyers have a trough supported on elastic stands which are rigidly fastened to the trough and a supporting frame. The trough is oscillated by a common crank drive. This vibration causes the load to move forward and upward. The movement is strictly related to vibrational parameters. In this study is the transitional behavior across resonance, during the starting of a single degree of freedom vibratory system excited by non-ideal DC motor. The mechanical system depends on the motion of the DC motor. The working rang of vibrational conveyers with cubic nonlinear spring and non-ideal vibration exciter has been analyzed analytically for primary resonance by the Method of Multiple Scales. Lyapunov exponents are numerically calculated and the results of numerical simulation are ploted.

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18

Escaler, Xavier, and Toufik Mebarki. "Full-Scale Wind Turbine Vibration Signature Analysis." Machines 6, no. 4 (December 7, 2018): 63. http://dx.doi.org/10.3390/machines6040063.

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A sample of healthy wind turbines from the same wind farm with identical sizes and designs was investigated to determine the average vibrational signatures of the drive train components during normal operation. The units were variable-speed machines with three blades. The rotor was supported by two bearings, and the drive train connected to an intermediate three-stage planetary/helical gearbox. The nominal 2 MW output power was regulated using blade pitch adjustment. Vibrations were measured in exactly the same positions using the same type of sensors over a six-month period covering the entire range of operating conditions. The data set was preliminary validated to remove outliers based on the theoretical power curves. The most relevant frequency peaks in the rotor, gearbox, and generator vibrations were detected and identified based on averaged power spectra. The amplitudes of the peaks induced by a common source of excitation were compared in different measurement positions. A wind speed dependency of broadband vibration amplitudes was also observed. Finally, a fault detection case is presented showing the change of vibration signature induced by a damage in the gearbox.

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19

Linh, N. N., V. A. Tuan, N. V. Tuan, and N. D. Anh. "Response analysis of undamped primary system subjected to base excitation with a dynamic vibration absorber integrated with a piezoelectric stack energy harvester." Vietnam Journal of Mechanics 44, no. 4 (December 30, 2022): 490–99. http://dx.doi.org/10.15625/0866-7136/17948.

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Dynamic vibration absorber (DVA) integrated with a piezoelectric stack energy harvesting subjected to base excitation is introduced in this paper. The system of dynamic vibration absorber and piezoelectric stack energy harvesting system (DVA-PSEH) has two functions, the first is to reduce vibrations for the primary system, and the second is to convert a part of the vibrational energy into electricity through the piezoelectric effect. The mechanical and electrical responses of the electromechanical system are determined by the complex amplitude method, then the numerical simulations are carried out to investigate the characteristics of DVA-PSEH.

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20

Ong, W. S., and Muhd Hafeez Zainulabidin. "Vibration Characteristics of Beam Structure Attached with Vibration Absorbers at its Vibrational Node and Antinode by Finite Element Analysis." JSE Journal of Science and Engineering 1, no. 1 (January 31, 2020): 7–16. http://dx.doi.org/10.30650/jse.v1i1.519.

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In this study, the vibration characteristics of fixed ends beam are analysed after attached with dynamic vibration absorbers at vibrational node and antinode by simulation using ANSYS APDL. This study aim to obtain the best location and optimum number of DVAs placed on the fixed ends beam in order to reduce vibration of beam. The dynamic vibration absorber were attached to the fixed ends beam vibrational node and antinode for a total of three modes of vibration. The 0.84 m long beam is modelled by ANSYS and divided into 21 elements where each element is 0.04 m. A harmonic force, Fo of 28.84 N is exerted at node 3 of beam element. Modal analysis and harmonic analysis are carried out in this study to obtain the natural frequency and frequency response of the beam respectively. The vibration characteristics of fixed ends beam without DVA and beam attached with DVAs were compared. The simulation results show reduction of vibration amplitude of the beam especially when the DVA were attached at the vibrational antinode. The DVA amplitude increase when amplitude of beam decreases. From this study, it is proved that DVAs absorb vibration of the beam structure. The best position to attach DVAs is the vibrational antinode based on the modes of vibration. The increment of DVAs number will not affect the percentage reduction of vibration amplitude as long as the DVAs are placed at optimum location.

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21

Sadjadi, SeyedAbdolreza, and Quentin Parker. "The Astrochemistry Implications of Quantum Chemical Normal Modes Vibrational Analysis." Galaxies 6, no. 4 (November 23, 2018): 123. http://dx.doi.org/10.3390/galaxies6040123.

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Understanding the molecular vibrations underlying each of the unknown infrared emission (UIE) bands (such as those found at 3.3, 3.4, 3.5, 6.2, 6.9, 7.7, 11.3, 15.8, 16.4, 18.9 μ m) observed in or towards astronomical objects is a vital link to uncover the molecular identity of their carriers. This is usually done by customary classifications of normal-mode frequencies such as stretching, deformation, rocking, wagging, skeletal mode, etc. A large literature on this subject exists and since 1952 ambiguities in classifications of normal modes via this empirical approach were pointed out by Morino and Kuchitsu New ways of interpretation and analyzing vibrational spectra were sought within the theoretical framework of quantum chemistry. Many of these methods cannot easily be applied to the large, complex molecular systems which are one of the key research interests of astrochemistry. In considering this demand, a simple and new method of analyzing and classifying the normal mode vibrational motions of molecular systems was introduced. This approach is a fully quantitative method of analysis of normal-mode displacement vector matrices and classification of the characteristic frequencies (fundamentals) underlying the observed IR bands. Outcomes of applying such an approach show some overlap with customary empirical classifications, usually at short wavelengths. It provides a quantitative breakdown of a complex vibration (at longer wavelengths) into the contributed fragments such as their aromatic or aliphatic components. In addition, in molecular systems outside the classical models of chemical bonds and structures where the empirical approach cannot be applied, this quantitative method enables an interpretation of vibrational motion(s) underlying the IR bands. As a result, further modifications in the structures (modeling) and the generation of the IR spectra (simulating) of the UIE carriers, initiated by proposing a PAH model, can be implemented in an efficient way. Here fresh results on the vibrational origin of the spectacular UIE bands based on astrochemistry molecular models, explored through the lens of the quantitative method applied to thousands of different vibrational motion matrices are discussed. These results are important in the context of protoplanetary nebulae and planetary nebulae where various molecular species have been uncovered despite their harsh environments.

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22

Keuleers, R., H. O. Desseyn, B. Rousseau, and C. Van Alsenoy. "Vibrational Analysis of Urea." Journal of Physical Chemistry A 103, no. 24 (June 1999): 4621–30. http://dx.doi.org/10.1021/jp984180z.

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23

Akalin, E., A. Yilmaz, and S. Akyuz. "Vibrational analysis of isonicotinamide." Journal of Molecular Structure 744-747 (June 2005): 881–86. http://dx.doi.org/10.1016/j.molstruc.2004.11.077.

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24

Kovács, A., and A. Szabó. "Vibrational analysis of perfluoroadamantane." Journal of Molecular Structure 519, no. 1-3 (February 2000): 13–19. http://dx.doi.org/10.1016/s0022-2860(99)00278-1.

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25

Mohaček-Grošev, Vlasta. "Vibrational analysis of hydroxyacetone." Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy 61, no. 3 (January 2005): 477–84. http://dx.doi.org/10.1016/j.saa.2004.05.007.

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26

Andruniow, Tadeusz, Marek Z. Zgierski, and Pawel M. Kozlowski. "Vibrational Analysis of Methylcobalamin." Journal of Physical Chemistry A 106, no. 7 (February 2002): 1365–73. http://dx.doi.org/10.1021/jp013271k.

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27

Qian, Weili, and Samuel Krimm. "Vibrational analysis of glutathione." Biopolymers 34, no. 10 (October 1994): 1377–94. http://dx.doi.org/10.1002/bip.360341009.

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28

Tao, Yunwen, Chuan Tian, Niraj Verma, Wenli Zou, Chao Wang, Dieter Cremer, and Elfi Kraka. "Recovering Intrinsic Fragmental Vibrations Using the Generalized Subsystem Vibrational Analysis." Journal of Chemical Theory and Computation 14, no. 5 (April 10, 2018): 2558–69. http://dx.doi.org/10.1021/acs.jctc.7b01171.

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29

Kudo, Subaru, Masashi Konno, Sumio Sugawara, and Tomio Yoshida. "Vibrational Analysis of Tuning Fork Gyroscope with Orthogonal Vibration Arms." Japanese Journal of Applied Physics 32, Part 1, No. 5B (May 30, 1993): 2310–13. http://dx.doi.org/10.1143/jjap.32.2310.

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Fan, Ruo-xun, Jie Liu, Yong-li Li, Jun Liu, and Jia-zi Gao. "Finite Element Investigation of the Effects of the Low-Frequency Vibration Generated by Vehicle Driving on the Human Lumbar Mechanical Properties." BioMed Research International 2018 (September 30, 2018): 1–9. http://dx.doi.org/10.1155/2018/7962414.

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Long-term exposure to low-frequency vibration generated by vehicle driving impairs human lumbar spine health. However, few studies have investigated how low-frequency vibration affects human lumbar mechanical properties. This study established a poroelastic finite element model of human lumbar spinal segments L2–L3 to perform time-dependent vibrational simulation analysis and investigated the effects of different vibrational frequencies generated by normal vehicle driving on the lumbar mechanical properties in one hour. Analysis results showed that vibrational load caused more injury to lumbar health than static load, and vibration at the resonant frequency generated the most serious injury. The axial effective stress and the radial displacement in the intervertebral disc, as well as the fluid loss in the nucleus pulposus, increased, whereas the pore pressure in the nucleus pulposus decreased with increased vibrational frequency under the same vibrational time, which may aggravate the injury degree of human lumbar spine. Therefore, long-term driving on a well-paved road also induces negative effects on human lumbar spine health. When driving on a nonpaved road or operating engineering machinery under poor navigating condition, the auto seat transmits relatively high vibrational frequency, which is highly detrimental to the lumbar spine health of a driver.

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31

Manesh, M. Kojouri, M. R. Hematiyan, M. Eghtesad, D. S. Necsulescu, and A. Rezazadeh. "Vibrating Loads Identification Using Inverse Acoustics in Fluid-Structure Interaction." Advanced Materials Research 433-440 (January 2012): 51–57. http://dx.doi.org/10.4028/www.scientific.net/amr.433-440.51.

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In numerous engineering systems it is essential to know the vibrational behavior. Often laser vibrometers are used for vibration measurements. But this point should be considered that method utilization because of complex volume of source of vibration is difficult. To alleviate this problem several other methods were recommended such as Near Field Acoustical Holography and Inverse Numerical Acoustics. Vibrational properties knowledge helps in design, control and reduce undesirable vibration, but direct measurement is difficult and contain significant errors. The aim of this paper is the presentation of an efficient method using acoustics that can obtain vibrational properties by measuring other quantities, like fluid pressure dynamics somewhere near the structure. This procedure is based on inverse analysis that is more intricate than direct analysis.

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Allouche, Rachid, Rachid Renane, and Rabah Haoui. "Prediction of the optimal speed of an aerospace vehicle by aerothermochemical analysis of hypersonic flow during atmospheric re-entry." Mechanics & Industry 21, no. 2 (2020): 208. http://dx.doi.org/10.1051/meca/2020006.

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The objective of this work is to predict the optimal speed of an aerospace vehicle by aerothermochemical analysis of the hypersonic flow during atmospheric re-entry, out of equilibrium vibrational and chemical behind a detached strong shock. This study focuses on the influence of the ionization process that plays a significant role in the absorption of heat, because the characteristics of hypersonic flows are that molecules behind a strong shock wave become vibrationally excited, partially or completely dissociated and ionized depending on their bond energy, and the velocity of flow. On the other hand, we present the mathematical model that governs the flow of reactive gas mixture out of vibrational and chemical equilibrium that is composed of 79% nitrogen N2 and 21% oxygen O2. Conservation and relaxation equations (chemistry-vibration) are presented with particular importance to the expression of source terms. The numerical resolution method used is based on physical modeling, governed by the Euler equations, supplemented by the equations of chemical kinetics using the finite difference method. The results obtained are in good agreement with the specialized literature.

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McDowell, Robin S., Burton J. Krohn, Herbert Flicker, and Mariena C. Vasquez. "Vibrational levels and anharmonicity in SF6—I. Vibrational band analysis." Spectrochimica Acta Part A: Molecular Spectroscopy 42, no. 2-3 (January 1986): 351–69. http://dx.doi.org/10.1016/0584-8539(86)80199-4.

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34

Rohwer, F., R. Hinze, and A. Guarnieri. "Extended Analysis of the Rotational Spectrum of HCCF." Zeitschrift für Naturforschung A 44, no. 2 (February 1, 1989): 131–38. http://dx.doi.org/10.1515/zna-1989-0208.

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Abstract The microwave spectrum of fluoroacetylene (HCCF) has been measured in the frequency region 35 -260 GHz. Rotational constants of the ground state and rotational as well as rotation-vibrational interaction constants of several excited states of the C - C - H (ν4) and the C - C - F (ν5) bending vibrations have been obtained.

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35

Ning, Si-Yuan, Jing-Wen Cao, Xiao-Yan Liu, Hao-Jian Wu, Xiao-Qing Yuan, Xiao-Tong Dong, Yi-Ning Li, Yan Jiang, and Peng Zhang. "Computational Analysis of Hydrogen Bond Vibrations of Ice III in the Far-Infrared Band." Crystals 12, no. 7 (June 26, 2022): 910. http://dx.doi.org/10.3390/cryst12070910.

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The hydrogen-disordered structure of ice III makes it difficult to analyze its vibrational spectrum theoretically. To clarify the contribution of hydrogen bonds (HBs), we constructed a 24-molecule supercell to mimic the real structure and performed first-principles density functional theory calculations. The calculated curve of phonon density of states showed good correspondence with the experimental data. Based on the theory of two kinds of HB vibrational modes, we analyzed the distributions of two-bond modes and four-bond modes. The energy splitting of these modes results in a flat vibrational band, which is a common phenomenon in high-pressure ice phases. These findings verified the general rule that there are two types of HB vibrations in ice, thereby furthering our understanding of HB interactions in water ice and their broad role in nature.

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Zhao, H., Z. An, and C. Q. Wu. "Lattice vibrational analysis of polyacene." European Physical Journal B 43, no. 1 (January 2005): 53–64. http://dx.doi.org/10.1140/epjb/e2005-00027-5.

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37

Anjaneyulu, A., and G. Ramana Rao. "Vibrational analysis of substituted benzaldehydes." Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy 55, no. 4 (April 1999): 749–60. http://dx.doi.org/10.1016/s1386-1425(98)00201-7.

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Jurevicius, M., J. Skeivalas, A. Kilikevicius, and V. Turla. "Vibrational analysis of length comparator." Measurement 103 (June 2017): 10–17. http://dx.doi.org/10.1016/j.measurement.2017.02.010.

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39

Taga, K., I. Shimizu, H. Fukui, T. K. Jain, and H. Okabayashi. "Vibrational analysis of 3-chloropropylsilane." Vibrational Spectroscopy 14, no. 2 (May 1997): 229–37. http://dx.doi.org/10.1016/s0924-2031(97)00009-x.

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Bunaciu, Andrei A., Hassan Y. Aboul-Enein, and Şerban Fleschin. "Vibrational Spectroscopy in Clinical Analysis." Applied Spectroscopy Reviews 50, no. 2 (September 25, 2014): 176–91. http://dx.doi.org/10.1080/05704928.2014.955582.

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41

Venkata Ramana Rao, P., and G. Ramana Rao. "Vibrational analysis of substituted phenols." Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy 58, no. 14 (December 2002): 3039–65. http://dx.doi.org/10.1016/s1386-1425(02)00101-4.

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Venkata Ramana Rao, P., and G. Ramana Rao. "Vibrational analysis of substituted phenols." Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy 58, no. 14 (December 2002): 3205–21. http://dx.doi.org/10.1016/s1386-1425(02)00102-6.

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43

Armstrong, D. R., J. Clarkson, and W. E. Smith. "Vibrational Analysis of trans-Azobenzene." Journal of Physical Chemistry 99, no. 51 (December 1995): 17825–31. http://dx.doi.org/10.1021/j100051a005.

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Kovács, Attila. "Vibrational analysis of 4-trifluoromethylphenol." Journal of Molecular Structure 645, no. 2-3 (January 2003): 193–98. http://dx.doi.org/10.1016/s0022-2860(02)00571-9.

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Kovács, Attila. "Vibrational analysis of 3-trifluoromethylphenol." Journal of Molecular Structure 650, no. 1-3 (May 2003): 99–104. http://dx.doi.org/10.1016/s0022-2860(03)00151-0.

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Kovács, Attila. "Vibrational analysis of 3-methylpyridine." Journal of Molecular Structure 482-483 (May 1999): 397–401. http://dx.doi.org/10.1016/s0022-2860(98)00769-8.

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Mowrey, Richard C., Bradley A. Williams, and Charles H. Douglass. "Vibrational Analysis of P4O6and P4O10." Journal of Physical Chemistry A 101, no. 32 (August 1997): 5748–52. http://dx.doi.org/10.1021/jp971072o.

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Shchur, Yaroslav. "Vibrational analysis of PbHPO4and PbDPO4crystals." physica status solidi (b) 246, no. 1 (January 2009): 102–9. http://dx.doi.org/10.1002/pssb.200844321.

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Ishikawa, H., and O. Kajimoto. "Vibrational Analysis of SiH2 (Ã1B1)." Journal of Molecular Spectroscopy 160, no. 1 (July 1993): 1–10. http://dx.doi.org/10.1006/jmsp.1993.1153.

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50

Sundius, T., J. Bandekar, and S. Krimm. "Vibrational analysis of crystalline triglycine." Journal of Molecular Structure 214 (December 1989): 119–42. http://dx.doi.org/10.1016/0022-2860(89)80009-2.

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