To see the other types of publications on this topic, follow the link: Displacemet.
Journal articles on the topic 'Displacemet'
Create a spot-on reference in APA, MLA, Chicago, Harvard, and other styles
Consult the top 50 journal articles for your research on the topic 'Displacemet.'
Next to every source in the list of references, there is an 'Add to bibliography' button. Press on it, and we will generate automatically the bibliographic reference to the chosen work in the citation style you need: APA, MLA, Harvard, Chicago, Vancouver, etc.
You can also download the full text of the academic publication as pdf and read online its abstract whenever available in the metadata.
Browse journal articles on a wide variety of disciplines and organise your bibliography correctly.
1
Guo, Qiang, Rui Cheng, and Zhan-hua Silber-Li. "Influence of Capillarity on Nano-Liter Flowrate Measuremet with Displacemet Method." Journal of Hydrodynamics 19, no. 5 (October 2007): 594–600. http://dx.doi.org/10.1016/s1001-6058(07)60158-9.
Full text
2
O’Reilly, Keara, Jocelyn R. Johnson, Lauren Wottlin, and Gordon E. Carstens. "8 President Oral Presentation Pick: Use of electronic feed intake systems to assess feed bunk displacement events as an indicator of aggressive feeding behavior in beef cattle." Journal of Animal Science 98, Supplement_4 (November 3, 2020): 1. http://dx.doi.org/10.1093/jas/skaa278.001.
Full textAbstract:
Abstract Animal variation in social dominance within a herd has been shown to be associated with performance, feed efficiency and animal well-being. The objective of this study was to quantify disruptive feeding events in cattle fed a high-grain diet. Crossbred steers (n = 85) housed in a pen with GrowSafe bunks were used in this study. An algorithm was developed to quantify displacement events defined as an animal being displaced by another within 5 sec. These feed bunk displacement events were further separated into either displacer events or displacee events. A displacer event was defined as an animal displacing another (aggressive). A displacee event was defined as an animal being displaced (submissive). The displacer events as a proportion of total displacement events were used to classify animals as aggressive versus submissive (±0.5 SD). Animals with fewer displacer events as a proportion of total displacement events (submissive < 0.5 SD) had greater (P < 0.05) frequency and duration of bunk visit events and head down duration than the animals who initiated more displacer events as a total of displacement events (aggressive > 0.5 SD). Additionally, submissive animals also had a slower (P < 0.05) bunk visit eating rate than aggressive animals. The results of this initial analysis found that due to the associations between feed bunk displacements and feeding behavior, there may be potential to correlate this trait with temperament and performance traits as well as be a potential indicator of feed efficiency in confined cattle.
3
Cheng, Hao, and Xiaoping Zhou. "A novel displacement-based rigorous limit equilibrium method for three-dimensional landslide stability analysis." Canadian Geotechnical Journal 52, no. 12 (December 2015): 2055–66. http://dx.doi.org/10.1139/cgj-2015-0050.
Full textAbstract:
Conventional stability analysis of landslides is investigated using the factor of safety of the entire sliding body, which provides no information concerning displacements of the analyzed landslides. In this paper, a novel displacement-based rigorous limit equilibrium method is proposed to investigate the displacements and stabilities of three-dimensional landslides. The relationship between the shear stresses acting on the base of the columns and the shear displacements is established based on the hyperbolic soil model, which can be directly obtained from direct shear tests. According to the displacement compatibility among the columns, the shear displacements of all columns can be determined by the vertical and horizontal displacements at a key point. Combining the six equilibrium conditions of the discretized columns with the nonlinear constitutive relation between stress and displacement of soils, the vertical displacement at the key point can be determined. By introducing the strength reduction technique into the displacement-based rigorous limit equilibrium method, the relationship between the reduction factor and the vertical displacement can be obtained. The displacement and the safety factor of three-dimensional landslides can be defined. Moreover, two cases are given to verify the robustness and precision of the present method in detail.
4
Feng, Zhibin, and Jinxin Gong. "Study on normalization of residual displacements for single-degree-of-freedom systems." Earthquake Spectra 37, no. 3 (January 25, 2021): 1758–84. http://dx.doi.org/10.1177/8755293020988014.
Full textAbstract:
Residual displacement spectrum is one of the most important means to predict the permanent deformation of structures after the earthquake, and various normalizations of residual displacements have generally been used for construction of the spectrum. However, the issue regarding the merits and drawbacks of each normalization has not yet been investigated thoroughly. A comparison between two normalizations that relate the residual displacements to the elastic and inelastic displacements is made in terms of the effect of ground motion and structural characteristics by means of the results of nonlinear time history analysis. The statistical results reveal that the residual-to-peak-inelastic displacement ratios have the advantages of small dispersion, samples without any outliers, and relatively symmetric distribution, which benefits from the strong correlation between residual and peak inelastic displacements. Moreover, the residual-to-peak-inelastic displacement ratios are almost independent of site conditions, significant duration, and natural periods. Consequently, the peak inelastic displacements are superior to the elastic ones as an intermediate step for residual displacements estimation, provided that the peak inelastic displacements are estimated with a low uncertainty. For providing alternatives to estimate residual displacement demands, the constant-strength residual displacement spectra are developed for both normalizations.
5
GRISO, GEORGES. "ASYMPTOTIC BEHAVIOR OF STRUCTURES MADE OF PLATES." Analysis and Applications 03, no. 04 (October 2005): 325–56. http://dx.doi.org/10.1142/s0219530505000613.
Full textAbstract:
The aim of this paper is to study the asymptotic behavior of a structure made of plates of thickness 2δ when δ → 0. This study is carried out within the frame of linear elasticity by using the unfolding method. It is based on several decompositions of displacements of the structure and on the passing to the limit in fixed domains.We begin by studying the displacements of a plate. We show that any displacement is the sum of an elementary displacement concerning the normal lines on the middle surface of the plate and a warping. An elementary displacement is linear with respect to the variable x3. It is written [Formula: see text] where [Formula: see text] is a displacement of the mid-surface of the plate. We show a priori estimates and convergence results when δ → 0. We characterize the limits of the unfolded displacements of a plate as well as the limits of the unfolded strained tensor.Then, we extend these results to structures made of plates. We show that any displacement of a structure is the sum of an elementary displacement of each plate and of a residual displacement. The elementary displacements of the structure (e.p.s.d.) coincide with elementary rod displacements in the junctions. Any e.p.s.d. is given by two functions belonging to H1( S ; ℝ3) where S is the skeleton of the structure (the set formed by the mid-surfaces of the plates constituting the surface). One of these functions, [Formula: see text], is the skeleton displacement. We show that [Formula: see text] is the sum of an extensional displacement and of an inextensional one. The first one characterizes the membrane displacements and the second one is a rigid displacement in the direction of the plates and it characterizes the flexion of the plates.Eventually, we pass to the limit as δ → 0 in the linearized elasticity system. On the one hand, we obtain a variational problem that is satisfied by the limit extensional displacement, and on the other hand, a variational problem satisfied by the limit of inextensional displacements.
6
Ben-Haim, S. A., O. Lichtenstein, and G. M. Saidel. "Mechanical analysis of extrapulmonary volume displacements in the thorax and abdomen." Journal of Applied Physiology 67, no. 5 (November 1, 1989): 1785–90. http://dx.doi.org/10.1152/jappl.1989.67.5.1785.
Full textAbstract:
Currently, the effect of intrathoracoabdominal, extrapulmonary volume displacements (Vep) are not well understood. Various clinical conditions can lead to volume displacements caused by gas or liquid accumulations. To analyze the pressure and volume changes that occur by Vep, we used a mathematical model of chest wall and lung mechanics that accounts for static changes associated with rib cage, diaphragm, abdomen, and lungs. By solving the model equations, we obtained simulations of the pleural and abdominal displacements that clearly differentiate the mechanisms involved. When abdominal displacement occurs, the reduction in lung volume is less than that caused by an equal displacement in pleural space. Abdominal displacement produces an increased pressure that expands the rib cage significantly, whereas pleural displacement does not produce a comparable action. Furthermore, our model predicts the conditions under which the work of inspiration is expected to increase as a consequence of these displacements. Finally, an important distinction is predicted between abdominal displacements caused by gas or liquid accumulation. Although an abdominal gas displacement tends to decrease the resting lung volume, the weight effect of a liquid displacement tends to increase the resting lung volume by pulling down the diaphragm.
7
Cao, Cai Qin, Chao Gao, and Hua Li. "A Semi-Analytical Solution of Single-Phase Elastic Foundation Three-Dimensional Static Characteristics." Advanced Materials Research 368-373 (October 2011): 2740–43. http://dx.doi.org/10.4028/www.scientific.net/amr.368-373.2740.
Full textAbstract:
Based on the single-phase elastic soil medium control equations and boundary conditions [1], by using the weighted residual method, a semi-analytical theory of elastic foundation three-dimensional static response was established. When the uniformly distributed loads were applied on the elastic half space foundation, the change rules of vertical displacement, lateral displacement, lengthways displacement were analyzed numerically, and compared with the theoretical solution [2]. The result shows that foundation displacements are completely symmetrical or antisymmetrical about x = 0 plane and y = 0 plane. The maximum vertical displacement appears in the center of load range, the maximum lateral and lengthways displacements appear at the edge of load range, and the displacements get smaller far from the loads.
8
Ebraheim, Nabil A., Hua Yang, Jike Lu, and Ashok Biyani. "Computer Evaluation of Second Tarsometatarsal Joint Dislocation." Foot & Ankle International 17, no. 11 (November 1996): 685–89. http://dx.doi.org/10.1177/107110079601701107.
Full textAbstract:
Using computer-assisted techniques, this study analyzes the mean contact area of the articular surface of the second tarsometatarsal joint. The articular contact area decreased proportionate to the displacement in both males and females, but it was consistently greater in males than in females for all simulated displacements. The reduction in the contact area was the highest with dorsolateral displacement compared with the lateral and dorsal displacements. Dorsolateral displacement of the second metatarsal of 3 mm led to 38.6% reduction in the contact area, compared with 33.1% and 20.2% reduction with lateral and dorsal displacements, respectively. This study shows that even minor degrees of displacement not apparent on plain radiographs lead to significant decrease in the contact area of the second tarsometatarsal joint. Careful evaluation of second tarsometatarsal injuries with computed tomography is recommended to detect minor degrees of displacement.
9
Ogushi, Matsuoka, Defilippi, and Pasquali. "Improvement of Persistent Scatterer Interferometry to Detect Large Non-Linear Displacements with the 2π Ambiguity by a Non-Parametric Approach." Remote Sensing 11, no. 21 (October 23, 2019): 2467. http://dx.doi.org/10.3390/rs11212467.
Full textAbstract:
Persistent scatterer interferometry (PSI) is commonly applied to monitor surface displacements with millimetric precision. However, this technique still has trouble estimating non-linear displacements because the algorithm is designed for the slow and linear displacements. Additionally, there is a variety of non-linear displacement types, and finding an appropriate displacement model for PSI is still assumed to be a fairly large task. In this paper, the conventional PSI technique is extended using a non-parametric non-linear approach (NN-PSI), and the performance of the extended method is investigated by simulations and actual observation data processing with TerraSAR-X. In the simulation, non-linear displacements are modeled by the magnitudes and periods of the displacement, and the evaluation of NN-PSI is conducted. According to the simulation results, the maximum magnitude of the displacement that can be estimated by NN-PSI is two and a half times the magnitude of the SAR sensor’s wavelength (2.5λ that is roughly equivalent to 8 cm for X-band, 14 cm for C-band, and 60 cm for L-band), and the period of the displacement is about three months. However, this displacement cannot be reconstructed by the conventional PSI due to the limitation, known as the 2π displacement ambiguity. The result of the observation data processing shows that a large displacement with the 2π ambiguity can be estimated by NN-PSI as the simulation results show, but the conventional PSI cannot reconstruct it. In addition, a different approach, Small BAseline Subset (SBAS), is applied to the same data to ensure the accuracy of results, and the correlation between NN-PSI and SBAS is 0.95, while that between the conventional PSI and SBAS is –0.66. It is concluded that NN-PSI enables the reconstruction of non-linear displacements by the non-parametric approach and the expansion of applications to measure surface displacements that could not be measured due to the limitations of the traditional PSI methods.
10
Paulay, T. "Seismic response of structural walls: recent developments." Canadian Journal of Civil Engineering 28, no. 6 (December 1, 2001): 922–37. http://dx.doi.org/10.1139/l01-054.
Full textAbstract:
It is postulated that for purposes of seismic design, the ductile behaviour of lateral force-resisting wall components, elements, and indeed the entire system can be satisfactorily simulated by bilinear forcedisplacement modeling. This enables displacement relationships between the system and its constituent components at a particular limit state to be readily established. To this end, some widely used fallacies, relevant to the transition from the elastic to the plastic domain of behaviour, are exposed. A redefinition of stiffness and yield displacement allows more realistic predictions of the important feature of seismic response, component displacements, to be made. The concepts are rational, yet very simple. Their applications are interwoven with the designer's intentions. Contrary to current design practice, whereby a specific global displacement ductility capacity is prescribed for a particular structural class, the designer can determine the acceptable displacement demand to be imposed on the system. This should protect critical components against excessive displacements. Specific intended displacement demands and capacities of systems comprising reinforced concrete cantilever and coupled walls can be estimated.Key words: ductility, displacements, reinforced concrete, seismic design, stiffness, structural walls.
11
Yu, Bo, Di Liu, and Lu Feng Yang. "Prediction of Residual Displacement of SDOF System from its Peak Inelastic Displacement." Applied Mechanics and Materials 275-277 (January 2013): 1415–18. http://dx.doi.org/10.4028/www.scientific.net/amm.275-277.1415.
Full textAbstract:
Residual displacement is an important measure of post-earthquake functionality of engineering structures. Empirical equations for prediction of residual displacement of SDOF system from its peak inelastic displacement were proposed through a comprehensive statistical analysis. An inelastic seismic analysis model including the P-Δ effect was employed to assess the residual and peak inelastic displacements of SDOF system under horizontal and vertical excitations. The correlation and empirical equations between residual and peak inelastic displacements were discussed based on 69 selected earthquake records. Results show that the correlation between residual and peak inelastic displacements are of high correlation, and the mean of residual-to-peak displacement ratio increases with the increase of period of vibration or stability factor. Furthermore, the coefficient of variation of residual-to-peak displacement ratio decreases with the increase of the period of vibration dramatically for rigid systems and is generally independent of the stability factor and the normalized yield strength.
12
Born, Sabine. "Saccadic Suppression of Displacement Does Not Reflect a Saccade-Specific Bias to Assume Stability." Vision 3, no. 4 (September 24, 2019): 49. http://dx.doi.org/10.3390/vision3040049.
Full textAbstract:
Across saccades, small displacements of a visual target are harder to detect and their directions more difficult to discriminate than during steady fixation. Prominent theories of this effect, known as saccadic suppression of displacement, propose that it is due to a bias to assume object stability across saccades. Recent studies comparing the saccadic effect to masking effects suggest that suppression of displacement is not saccade-specific. Further evidence for this account is presented from two experiments where participants judged the size of displacements on a continuous scale in saccade and mask conditions, with and without blanking. Saccades and masks both reduced the proportion of correctly perceived displacements and increased the proportion of missed displacements. Blanking improved performance in both conditions by reducing the proportion of missed displacements. Thus, if suppression of displacement reflects a bias for stability, it is not a saccade-specific bias, but a more general stability assumption revealed under conditions of impoverished vision. Specifically, I discuss the potentially decisive role of motion or other transient signals for displacement perception. Without transients or motion, the quality of relative position signals is poor, and saccadic and mask-induced suppression of displacement reflects performance when the decision has to be made on these signals alone. Blanking may improve those position signals by providing a transient onset or a longer time to encode the pre-saccadic target position.
13
Zhou, Bao Feng, Ting Su Song, Rui Zhi Wen, and Li Li Xie. "Permanent Displacement Identification Analysis in 2011 Mw9.0 Tohoku Earthquake, Japan." Applied Mechanics and Materials 580-583 (July 2014): 1533–37. http://dx.doi.org/10.4028/www.scientific.net/amm.580-583.1533.
Full textAbstract:
Permanent displacement identification is one of key topics in near-fault ground-motion research. A new method based on Hermit interpolation and flatness technique is proposed to determine permanent displacements, since the Iwan law is not applicable in Mw9.0 Tohoku earthquake permanent displacement recognition. The method is then tested by coseismic displacements resulted from GPS station nearby. Results show that: the causes for strong motion record baseline drift are very complex so that Iwan method is not suitable for permanent displacements identification in the Mw9.0 Tohoku Earthquake, while the new baseline correction method combining Hermit interpolation and flatness technique is suitable for permanent displacement analysis of near-fault ground motion in 2011 Mw9.0 Tohoku Earthquake.
14
Mefferd, Antje S. "Tongue- and Jaw-Specific Contributions to Acoustic Vowel Contrast Changes in the Diphthong /ai/ in Response to Slow, Loud, and Clear Speech." Journal of Speech, Language, and Hearing Research 60, no. 11 (November 9, 2017): 3144–58. http://dx.doi.org/10.1044/2017_jslhr-s-17-0114.
Full textAbstract:
Purpose This study sought to determine decoupled tongue and jaw displacement changes and their specific contributions to acoustic vowel contrast changes during slow, loud, and clear speech. Method Twenty typical talkers repeated “see a kite again” 5 times in 4 speech conditions (typical, slow, loud, clear). Speech kinematics were recorded using 3-dimensional electromagnetic articulography. Tongue composite displacement, decoupled tongue displacement, and jaw displacement during /ai/, as well as the distance between /a/ and /i/ in the F1–F2 vowel space, were examined during the diphthong /ai/ in “kite.” Results Displacements significantly increased during all 3 speech modifications. However, jaw displacements increased significantly more during clear speech than during loud and slow speech, whereas decoupled tongue displacements increased significantly more during slow speech than during clear and loud speech. In addition, decoupled tongue displacements increased significantly more during clear speech than during loud speech. Increases in acoustic vowel contrast tended to be larger during slow speech than during clear speech and were predominantly tongue-driven, whereas those during clear speech were fairly equally accounted for by changes in decoupled tongue and jaw displacements. Increases in acoustic vowel contrast during loud speech were smallest and were predominantly tongue-driven, particularly in men. Conclusions Findings suggest that task-specific patterns of decoupled tongue and jaw displacement change and task-specific patterns of decoupled tongue and jaw contributions to vowel acoustic change across these speech modifications. Clinical implications are discussed.
15
Zhe, J., and S. Greenhalgh. "Extrapolation of Vector (Elastic) Displacements by Displacement Potential Field Continuation." Exploration Geophysics 24, no. 3-4 (September 1993): 873–77. http://dx.doi.org/10.1071/eg993873.
Full text
16
Tajduś, Krzysztof. "MINING-INDUCED SURFACE HORIZONTAL DISPLACEMENT: THE CASE OF BW PROSPER HANIEL MINE / ANALIZA PRZEMIESZCZEŃ POZIOMYCH POWIERZCHNI TERENU WYWOŁANYCH PODZIEMNĄ EKSPLOATACJĄ GÓRNICZĄ NA PRZYKŁADZIE KOPALNI BW PROSPER HANIEL." Archives of Mining Sciences 58, no. 4 (December 1, 2013): 1037–55. http://dx.doi.org/10.2478/amsc-2013-0072.
Full textAbstract:
Abstract The paper presents a wide-ranged analysis of horizontal displacements in the region of underground mining exploitation. Initially, various theories pertaining to the determination of mining-induced horizontal displacement are discussed, followed by a complex study on horizontal displacements measured for a selected example region of the German coal mine BW Prosper Haniel, as well as the determination of displacement factor B.
17
Moehle, J. P. "Displacement-Based Design of RC Structures Subjected to Earthquakes." Earthquake Spectra 8, no. 3 (August 1992): 403–28. http://dx.doi.org/10.1193/1.1585688.
Full textAbstract:
Earthquake induced structural displacements are a main case of damage in structures subjected to earthquakes. Simple techniques for estimating structural displacements enable development of a design approach based explicitly on expected displacements. This approach is useful both in planning stages where decisions can be made to control displacement demands and in final design stages where details for structural and nonstructural elements are established. Comparison with more conventional force- or ductility-based approaches to design indicates that a displacement-based approach to design is both simple and effective.
18
Song, Zhan Ping, Jing Liu, and An Nan Jiang. "Studying the Three Dimensional Excavation Effect Affecting the Monitoring Displacement of Metro Station." Advanced Materials Research 594-597 (November 2012): 1285–89. http://dx.doi.org/10.4028/www.scientific.net/amr.594-597.1285.
Full textAbstract:
In tunnel construction process, Because monitoring points setting always get behind with tunnel heading and occurred space effect which induces displacement loss and affects the monitoring accuracy. Studying tunnel space affect has important meaning to the monitoring data analysis. The paper takes Dalian Metro Station as research back ground, adopted three dimensional elastic-plastic numerical test method and carried out the excavation process simulation. Studied the convergence displacement and sedimentation displacement variation regulation along with the distance to tunnel heading face. The simulation results state that the nearer to the tunnel heading, the displacements of surrounding rock are smaller. Analyzed the ratio of displacement loss induced by space effect and amended the monitoring displacements of Dalian Metro Station.
19
Dong, Longkai, Chao Wang, Yixian Tang, Fuquan Tang, Hong Zhang, Jing Wang, and Wei Duan. "Time Series InSAR Three-Dimensional Displacement Inversion Model of Coal Mining Areas Based on Symmetrical Features of Mining Subsidence." Remote Sensing 13, no. 11 (May 29, 2021): 2143. http://dx.doi.org/10.3390/rs13112143.
Full textAbstract:
The three-dimensional (3-D) displacements of mining areas is the basis of studying the mining subsidence law and obtaining surface movement parameters. The traditional multi-temporal interferometry synthetic aperture radar (InSAR) technology can only obtain the surface deformation in line-of-sight (LOS) direction, even if some methods can obtain the 3-D displacements of mining area based on InSAR. However, it has high data requirements for data types, which are not conducive to the inversion of 3-D displacements. In this paper, the symmetry of the surface basin caused by mining subsidence under different mining degrees is analyzed. According to the basic symmetrical features of mining subsidence—that the surface vertical displacement and horizontal displacement in near horizontal coal seam is symmetrical with respect to the main section of the basin, combined with time series InSAR technology (TS-InSAR)—a novel method for retrieving the 3-D displacement results from a single-geometry InSAR dataset based on symmetrical features (hereafter referred to as the SGI-SF method) is proposed. The SGI-SF method first generates multi-temporal observations of LOS displacement from a single-geometry InSAR dataset, and then transforms them into multi-temporal observations of 3-D displacement datasets according to symmetrical features. There is no necessity to obtain the surface movement parameters from the measured data to calculate 3-D displacement fields. Finally, the time series of 3-D displacements are estimated from multi-temporal 3-D displacements using the singular value decomposition (SVD) method. Nine descending Sentinel-1 images from the Yulin mining area of China are used to test the proposed SGI-SF method. The results show that the average root mean square errors (RMSE) in the vertical and horizontal direction of the three-dimensional deformations are approximately 9.28 mm and 13.10 mm, respectively, which are much smaller than mining-induced displacements and can provide support for deformation monitoring in mining areas.
20
Xia, Yong Jun, and Qian Miao. "Large Deformation Geometric Nonlinear Beam Element Based on U.L. Format." Advanced Materials Research 446-449 (January 2012): 3596–603. http://dx.doi.org/10.4028/www.scientific.net/amr.446-449.3596.
Full textAbstract:
Based on the geometric deformation of the Euler-Bernoulli beam element, the geometric nonlinear Euler-Bernoulli beam element based on U.L. formulation is derived. The element’s transverse first-order displacement field is constructed using the cubic Hermite interpolation polynomial, and the first-order Lagrange interpolation polynomial is used for the axial displacement field. Then the additional displacements induced from the rotation of the elemental are included into the transverse and longitudinal displacement fields, so those displacement fields are expressed as the quadratic function of nodal displacement. Afterwards the nonlinear finite element formulas of Euler-Bernoulli beam element under the form of U.L. formulation are derived using Cauchy strain tensor and the principle of virtual displacements. The total equilibrium equation and tangent stiffness for large displacement geometric nonlinear analysis of frame are obtained in the total coordinate system. The correctness of this element is proved by typical example.
21
Liang, Bing, Wei Liu, Kun Liu, Mengde Zhou, Yang Zhang, and Zhenyuan Jia. "A Displacement Field Perception Method for Component Digital Twin in Aircraft Assembly." Sensors 20, no. 18 (September 10, 2020): 5161. http://dx.doi.org/10.3390/s20185161.
Full textAbstract:
Full-field displacement perception and digital twins for core components play a crucial role in the precision manufacturing industry, such as aviation manufacturing. This paper presents a real-time full-field displacement perception method for the combination of online multipoint displacement monitoring and matrix completion theory. Firstly, a conceptual full-field displacement perception model based on the observed information of the multi-points is established. To obtain the full-field displacements of a core component, the component is divided into plentiful discrete points, including observed and unobserved points, based on which the relationship between the observed points and the full-field displacements is established. Then, the solution method of the full-field displacement perception model is proposed. Based on the matrix completion principle and the big data of the simulation, the optimization problem is employed to work out the model and, meanwhile, the pseudo-code is put forward. Finally, the full-field displacement perception experiments are performed. Repeated experiments show that the max error of the displacements calculated by the proposed method can be less than 0.094 mm and the median error can be less than 0.054 mm, while the average time frame can be less than 0.48 s, which is promising considering the high precision and efficiency requirements of the assembly of large aircraft.
22
Okuno, R., and Z. Xu. "Efficient Displacement of Heavy Oil by Use of Three Hydrocarbon Phases." SPE Journal 19, no. 05 (March 12, 2014): 956–73. http://dx.doi.org/10.2118/165470-pa.
Full textAbstract:
Summary Mixtures of oil with solvent gas can exhibit three-hydrocarbon-phase behavior at reservoir conditions, where the solvent-rich liquid (L2) phase coexists with the gaseous (V) and oleic (L1) phases. Three-hydrocarbon-phase behavior has been studied in the literature for carbon dioxide (CO2) floods and enriched-gas floods at relatively low temperatures. Prior research on heavy-oil displacement with enriched gas presented that displacement efficiency at a given throughput can be nonmonotonic with respect to gas enrichment. Slimtube experiments for such displacements showed that oil recovery increased first, then decreased, and increased again with increasing gas enrichment. An optimum displacement with a high efficiency of more than 90% was observed when three-hydrocarbon-phase flow was present. However, detailed mechanisms for such an optimum displacement with three phases have not been explained in the literature. In this research, we investigate mass transfer on multiphase transitions between two and three phases for three-hydrocarbon-phase displacements. Simple conditions are derived for the multiphase transitions that yield high local displacement efficiency by three hydrocarbon phases. The derivation is based on the generalized mass conservation for a multiphase transition in 1D gas injection. The conditions derived are applied to explain nonmonotonic oil recovery in quaternary displacements and the West Sak oil displacements. Oil recovery at a given throughput can be nonmonotonic with respect to pressure or gas enrichment. Such a nonmonotonic trend can occur when local oil displacement by three hydrocarbon phases becomes more efficient, but slower, with decreasing pressure or decreasing gas enrichment. An optimum pressure or enrichment can occur as a consequence of the balance between the local displacement efficiency and the propagation rate of three hydrocarbon phases. The West Sak oil displacement with enriched gas studied in this research yields a high displacement efficiency of more than 90% at 1.5 hydrocarbon pore volumes (PV) injected at 53% methane (C1) dilution.
23
Xiao, Peng Peng, Li Lan Gao, Zhi Dong Liu, and Chun Qiu Zhang. "The Micro-Mechanical Behavior of Articular Cartilage under Continuous Sliding Load." Applied Mechanics and Materials 395-396 (September 2013): 654–57. http://dx.doi.org/10.4028/www.scientific.net/amm.395-396.654.
Full textAbstract:
As a viscoelastic and nonlinear connective tissue, articular cartilage bears continuous sliding load in the daily activities. The optimized digital image correlation (DIC) technique was applied to investigate the effect of sliding rate and compressive strain on the normal displacement of different layers in pig articular cartilage under sliding load. The normal displacements of different layers in cartilage increase gradually with sliding going on with given sliding rate and compressive strain. Experiments showed that the normal displacement of superficial layer is the largest, the normal displacement of deep layer is the smallest and the normal displacement of middle layer is between superficial layer and deep layer, and found that the normal displacements of different layers in cartilage increase with increasing compressive strains, but decrease with increasing sliding rates. The normal displacement of different layers are different under continuous sliding load.
24
Yu, Bo, Lu Feng Yang, and Di Liu. "Probabilistic Characteristics of Residual Displacements of SDOF Systems." Applied Mechanics and Materials 275-277 (January 2013): 1419–22. http://dx.doi.org/10.4028/www.scientific.net/amm.275-277.1419.
Full textAbstract:
Probabilistic residual displacement analysis plays an important role in determination of technical or economical feasibility of repairing the damaged emgineering structures after an earthquake. Probabilistic characteristics of residual displacements of SDOF systems were quantificationally investigated in this study through a comprehensive statistical analysis. The influences of the P-Δ effect, period of vibration, normalized yield strength and post-yield stiffness ratio on probabilistic characteristics of residual displacements were investigated based on 69 selected earthquake records. In particular, the probability models for the normalized residual displacements were proposed and tested. Results show that the P-Δ effect and post-yield stiffness ratio have significant impacts on the residual displacements; the period of vibration also obviously influences the residual displacements for rigid systems; the residual displacement can be described as the Lognormal distribution variable.
25
Bolton, Philip S., Elie Hammam, and Vaughan G. Macefield. "Neck movement but not neck position modulates skin sympathetic nerve activity supplying the lower limbs of humans." Journal of Neurophysiology 119, no. 4 (April 1, 2018): 1283–90. http://dx.doi.org/10.1152/jn.00043.2017.
Full textAbstract:
We previously showed that dynamic, but not static, neck displacement modulates muscle sympathetic nerve activity (MSNA) to lower limbs of humans. However, it is not known whether dynamic neck displacement modulates skin sympathetic nerve activity (SSNA). Tungsten microelectrodes inserted into the common peroneal nerve were used to record SSNA in 5 female and 4 male subjects lying supine on a table that fixed their head in space but allowed trapezoidal ramp (8.1 ± 1.2°/s) and hold (17.5° for 53 s) or sinusoidal (35° peak to peak at 0.33–0.46 Hz) horizontal displacement of the body about the head. SSNA recordings were made before, during, and after trapezoidal and sinusoidal displacements of the body. Spike frequency analysis of trapezoidal displacements and cross-correlation analysis during sinusoidal displacements revealed that SSNA was not changed by trapezoid body-only displacement but was cyclically modulated during sinusoidal angular displacements (median, 95% CI: 27.9%, 19.6–48.0%). The magnitude of this modulation was not statistically ( P > 0.05) different from that of cardiac and respiratory modulation at rest (47.1%, 18.7–56.3% and 48.6%, 28.4–59.3%, respectively) or during sinusoidal displacement (10.3%, 6.2–32.1% and 26.9%, 13.6–43.3%, respectively). Respiratory frequency was entrained above its resting rate (0.26 Hz, 0.2–0.29 Hz) during sinusoidal neck displacement; there was no significant difference ( P > 0.05) between respiratory frequency (0.38 Hz, 0.25–0.49 Hz) and sinusoidal displacement frequency (0.39 Hz, 0.35–0.42 Hz). This study provides evidence that SSNA is modulated during neck movement, raising the possibility that neck mechanoreceptors may contribute to the cutaneous vasoconstriction and sweat release associated with motion sickness. NEW & NOTEWORTHY This study demonstrates that dynamic, but not static, stretching of the neck modulates skin sympathetic nerve activity in the lower limbs.
26
Cao, Xiao Hui, and Qing Ying Kang. "Simulative Analysis of Structure Vibration of Diesel Engine Based on Finite Element Method." Applied Mechanics and Materials 226-228 (November 2012): 17–20. http://dx.doi.org/10.4028/www.scientific.net/amm.226-228.17.
Full textAbstract:
The simulated prediction of the structural vibration of diesel engine has been made in this paper. The displacement maps on different frequencies were obtained by using finite element model. The FFT (Fast Fourier Transform Algorithm) was used to the displacement data of the parts where the vibration is strong. So, the displacement spectrum was obtained on those points. The study shows that response displacements between 60~500Hz are bigger than others. This is due to the rigid displacement of the diesel engine. There are some other big response displacements around 800Hz, 1400Hz and 1800Hz.This is the result of local vibration of the oil pan, flywheel shell and gear room cover. Improve the three parts structure can effectively reduce vibration of the diesel engine.
27
Adamcová, Dana, Stanislav Bartoň, Piotr Osinski, Grzegorz Pasternak, Anna Podlasek, Magdalena Daria Vaverková, and Eugeniusz Koda. "Analytical Modelling of MSW Landfill Surface Displacement Based on GNSS Monitoring." Sensors 20, no. 21 (October 22, 2020): 5998. http://dx.doi.org/10.3390/s20215998.
Full textAbstract:
Displacements of landfills play an important role in the reclamation process and geotechnical safety improvement of such sites. Landfill settlements are defined as a vertical displacement of waste body due to compression, degradable nature of the waste, and creep phenomenon of the waste particles. Waste composition is more diverse than natural soil. Thus, it has to be properly placed and compacted since the landfill body will continuously settle down. Several models of the landfill displacement estimation have already been developed. The aim of the present study was: (i) to review the methods of landfill settlements computation and (ii) to propose the model allowing landfill body displacements simulation based on monitoring datasets applying a Global Navigation Satellite Systems (GNSS) measurement. The new model employs Gauss-Newton iteration and Runge-Kutta methods to estimate landfill surface displacements. The objectives were to analyse and mathematically describe the landfill body displacements. The GNSS geodetic survey and computations allowed concluding that the landfill body has been transformed over the years. The results revealed that the curves of waste displacement are in agreement with the measured total displacement of the landfill, and all curves corresponding to waste displacement are perpendicular to the active edge of the landfill. In the period of a maximum of 4.5 years after the waste deposition with a layer of up to 16.2 m thickness, the phenomenon of expansion was observed, which then disappears, and more settlement occurs due to the gravity of upper layers. The analysed landfill as a whole does not experience significant displacements. Neither of the slope failures are observed, even for large inclination.
28
Olaszek, Piotr, Andrzej Świercz, and Francesco Boscagli. "The Integration of Two Interferometric Radars for Measuring Dynamic Displacement of Bridges." Remote Sensing 13, no. 18 (September 14, 2021): 3668. http://dx.doi.org/10.3390/rs13183668.
Full textAbstract:
Measurements of displacements of bridges under dynamic load are particularly difficult in the case of structures where access to the area under the tested structure is impossible. Then, remote measurement methods are preferred, such as interferometric radar. Interferometric radar has high accuracy when measuring displacement in the direction of its target axis. The problems appear when a bridge vibrates in two directions: horizontal (lateral or longitudinal) and vertical. The use of one radar to measure those vibrations may be impossible. This paper presents the application of a set of two interferometric radars to measure vertical vibration and horizontal longitudinal vibration with high accuracy. The method was positively verified by experimental tests on two railway bridges characterized by different levels of horizontal displacement. The accuracy of the radar measurements was tested by the direct measurement of vertical displacements using inductive gauges. In conclusion, in the case of vertical displacement measurements using one interferometric radar, the influence of horizontal displacements should be excluded. In the case of locating radars at the area of bridge supports, it is necessary to either use a set of two radars or first investigate the magnitude of possible horizontal displacements in relation to vertical displacements.
29
Amancharla, Maneesh R., Joseph R. Rodarte, and Aladin M. Boriek. "Modeling the kinematics of the canine midcostal diaphragm." American Journal of Physiology-Regulatory, Integrative and Comparative Physiology 280, no. 2 (February 1, 2001): R588—R597. http://dx.doi.org/10.1152/ajpregu.2001.280.2.r588.
Full textAbstract:
The hypotheses that the chest wall insertion (CW) is displaced laterally during inspiration and that this displacement is essential in maintaining muscle curvature of the costal diaphragmatic muscle fibers were tested. With the use of data from three dogs, caudal, lateral, and ventral displacements of CW during both quiet, spontaneous inspiration and during inspiratory efforts against an occluded airway were observed and recorded. We have developed a kinematic model of the diaphragm that incorporates these displacements. This model describes the motions of the muscle fibers and central tendon; the displacements of the midplane, muscle-tendon junction (MTJ), CW, and center of the muscle fiber-central tendon arcs are modeled as functions of muscle fiber length. In the model, the center of the fiber arcs and MTJ both move caudally parallel to the midplane during inspiration, whereas CW moves both caudally and laterally. The observed lateral displacement of CW and the observed caudal displacement of MTJ, as functions of muscle fiber length, both approximate well the theoretical displacements that would be necessary to maintain curvature of the fiber arcs. In confirming our hypotheses, we have found that lateral displacement of CW is a mechanism by which changes in the shape of the costal diaphragm, as described by its curvature, are limited.
30
Wang, Zengli, Lin Liu, Hanlin Zhou, and Minxuan Lan. "Crime Geographical Displacement: Testing Its Potential Contribution to Crime Prediction." ISPRS International Journal of Geo-Information 8, no. 9 (September 2, 2019): 383. http://dx.doi.org/10.3390/ijgi8090383.
Full textAbstract:
Crime geographical displacement has been examined in many Western countries. However, little is known about its existence, distribution, and potential predictive ability in large cities in China. Compared to the existing research, this study contributes to the current research in three ways. (1) It provides confirmation that crime geographical displacement exists in relation to burglaries that occur in a large Chinese city. (2) A crime geographical displacement detector is proposed, where significant displacements are statistically detected and geographically displayed. Interestingly, most of the displacements are not very far from one another. These findings confirm the inferences in the existing literature. (3) Based on the quantitative results detected by the crime geographical displacement detector, a crime prediction method involving crime geographical displacement patterns could improve the accuracy of the empirical crime prediction method by 7.25% and 3.1 in the capture rate and prediction accuracy index (PAI), respectively. Our current study verifies the feasibility of crime displacement for crime prediction. The feasibility of the crime geographical displacement detector and results should be verified in additional areas.
31
Won, Jongbin, Jong-Woong Park, Junyoung Park, Junsik Shin, and Minyong Park. "Development of a Reference-Free Indirect Bridge Displacement Sensing System." Sensors 21, no. 16 (August 21, 2021): 5647. http://dx.doi.org/10.3390/s21165647.
Full textAbstract:
Bridge displacement measurements are important data for assessing the condition of a bridge. Measuring bridge displacement under moving vehicle loads is helpful for rating the load-carrying capacity and evaluating the structural health of a bridge. Displacements are conventionally measured using a linear variable differential transformer (LVDT), which needs stable reference points and thus prohibits the use of this method for measuring displacements for bridges crossing sea channels, large rivers, and highways. This paper proposes a reference-free indirect bridge displacement sensing system using a multichannel sensor board strain and accelerometer with a commercial wireless sensor platform (Xnode). The indirect displacement estimation method is then optimized for measuring the structural displacement. The performance of the developed system was experimentally evaluated on concrete- and steelbox girder bridges. In comparison with the reference LVDT data, the maximum displacement error for the proposed method was 2.17%. The proposed method was successfully applied to the displacement monitoring of a tall bridge (height = 20 m), which was very difficult to monitor using existing systems.
32
Katona, Tamás János, László Tóth, and Erzsébet Győri. "Fault Displacement Hazard Analysis Based on Probabilistic Seismic Hazard Analysis for Specific Nuclear Sites." Applied Sciences 11, no. 15 (August 3, 2021): 7162. http://dx.doi.org/10.3390/app11157162.
Full textAbstract:
Permanent ground displacements/deformations caused by earthquakes can seriously challenge the safety of the nuclear power plants. The state-of-the-art hazard analysis methods provide a fault displacement hazard curve, i.e., the annual probability of given measure of displacement will be exceeded. The evaluation of ground displacement hazard requires great effort, empirical evidence, and sufficient data for the characterization of the fault activity and capability to cause permanent surface displacement. There are practical cases when the fault at the site area revealed to be active, and, despite this, there are no sufficient data for the evaluation of permanent ground displacements hazard and for judging on the safety significance of permanent ground displacement. For these cases, a methodology is proposed that is based on the seismotectonic modelling and results of the probabilistic seismic hazard analysis. The method provides conservative assessment of the annual probability of fault displacement that allows the decision whether permanent displacement hazard is relevant to nuclear power plant safety. The feasibility and applicability of the method is demonstrated for the Paks site, Hungary.
33
Cai, Z., and R. J. Bathurst. "Seismic-induced permanent displacement of geosynthetic-reinforced segmental retaining walls." Canadian Geotechnical Journal 33, no. 6 (December 1, 1996): 937–55. http://dx.doi.org/10.1139/t96-123.
Full textAbstract:
This paper describes the application of conventional displacement methods to estimate seismic-induced permanent displacements of geosynthetic-reinforced segmental retaining walls constructed on firm foundations. Permanent displacements associated with three sliding mechanisms are investigated: (1) external sliding along the base of the total wall structure; (2) internal sliding along a reinforcement layer and through the facing column; and (3) block interface shear between facing column units. A pseudostatic method based on the Mononobe-Okabe earth pressure theory is used to determine the value of critical acceleration associated with each potential failure mechanism. Newmark's sliding block displacement method and a number of emperical methods are briefly summarized and can be used to estimate the permanent displacements of segmental retaining walls. An example is given to illustrate the application of the methods presented. Key words: segmental retaining walls, geosynthetics, seismic, Newmark, sliding block, displacement methods.
34
Baba-Kishi, K. Z. "Direct observation ofB-site cation displacements in Pb-based complex perovskite relaxor oxides." Journal of Applied Crystallography 44, no. 1 (November 27, 2010): 111–21. http://dx.doi.org/10.1107/s0021889810042214.
Full textAbstract:
Electron diffraction patterns recorded using a scanning transmission electron microscope (STEM) from PbMg1/3Nb2/3O3(PMN) crystallites and PbZn1/3Nb2/3O3(PZN) crystals show weak and systematic continuous diffuse streaking along the 〈110〉 directions. Detailed high-angle annular dark-field (HAADF) images recordedviaan aberration-corrected STEM show that theB-site cations in PMN and PZN undergo correlated and long-range displacements towards the Pb2+ions on the (110) planes. The planarB-site displacement measured from the centres of the octahedra is about 0.3–0.5 Å in PMN and about 0.20–0.4 Å in PZN. In the HAADF images of the PMN crystallites and PZN crystals studied, there is insufficient evidence for systematic long-range planar displacements of the Pb2+ions. The observed Pb2+ion displacements in PMN and PZN appear randomly distributed, mostly displaced along 〈110〉 towards theB-site columns. There is also evidence of possible stress-related distortion in certain unit cells of PMN. In the relaxors studied, two distinct types of displacements were observed: one is the long-range planarB-site spatial displacement on the (110) planes, correlated with the Pb2+ions, possibly resulting in the observed diffuse streaking; the other is short-range Pb2+ion displacement on the (110) planes. The observed displacement status indicates a mutual attraction between the Pb ions and theB-site cations in which theBsites undergo the largest spatial displacements towards the Pb ions along 〈110〉.
35
Okuno, R., R. T. T. Johns, and K. Sepehrnoori. "Mechanisms for High Displacement Efficiency of Low-Temperature CO2 Floods." SPE Journal 16, no. 04 (June 28, 2011): 751–67. http://dx.doi.org/10.2118/129846-pa.
Full textAbstract:
Summary CO2 floods at temperatures typically below 120°F can involve complex phase behavior, where a third CO2-rich liquid (L2) phase coexists with the oleic (L1) and gaseous (V) phases. Results of slimtube measurements in the literature show that an oil displacement by CO2 can achieve high displacement efficiency of more than 90% when three hydrocarbon phases coexist during the displacement. However, the mechanism for the high-displacement efficiency is uncertain because the complex interaction of phase behavior with flow during the displacement is not fully understood. In this paper, we present the first detailed study of three-phase behavior predictions and displacement efficiency for low-temperature CO2 floods. Four-component EOS models are initially used to investigate systematically the effects of pressure, temperature, and oil properties on development of three-phase regions and displacement efficiency. Multicomponent oil displacements by CO2 are then considered. We use a compositional reservoir simulator capable of robust three-phase equilibrium calculations. Results show that high displacement efficiency of low-temperature CO2 floods is a consequence of both condensing and vaporizing behavior. The L2 phase serves as a buffer between the immiscible V and L1 phases within the three-phase region. Components in the L1 phase first transfer efficiently to the L2 phase near a lower critical endpoint (LCEP). These oil components then transfer to the V phase near an upper critical endpoint (UCEP) at the trailing edge of the three-phase region. The CEPs are defined where two of the three coexisting phases merge in the presence of the other immiscible phase. Unlike two-phase displacements, condensation and vaporization of intermediate components occur simultaneously within the three-phase region. The simultaneous condensing/vaporizing behavior involving the CEPs is also confirmed for simulations of several west Texas oil displacements. Quaternary fluid models can predict qualitatively the complex displacements because four is the minimum number of components to develop CEP behavior in composition space at a fixed temperature and pressure.
36
Machida, Kenji, and Yoshimasa Suzuki. "Examination of Accuracy of the Singular Stress Field Near a Crack-Tip by Digital Image Correlation." Key Engineering Materials 321-323 (October 2006): 32–37. http://dx.doi.org/10.4028/www.scientific.net/kem.321-323.32.
Full textAbstract:
Displacements obtained experimentally normally are including errors that make it impossible to extract stresses strains with high accuracy using the raw displacement data. In the infinitesimal deformation within the elastic region of a steel or an aluminum alloy, the quantity of displacement is less than 1 pixel, and analysis accuracy deteriorates. We have developed a system which employs the 2-D intelligent hybrid method and can analyze the displacement more exactly in the sub-pixel field. By using the Newton-Raphson method in conjunction with 2nd order deformation gradients, it is demonstrated that this method can accurately extract stress intensity factors from a set of measured displacements.
37
Abellán, A., M. Jaboyedoff, T. Oppikofer, and J. M. Vilaplana. "Detection of millimetric deformation using a terrestrial laser scanner: experiment and application to a rockfall event." Natural Hazards and Earth System Sciences 9, no. 2 (March 17, 2009): 365–72. http://dx.doi.org/10.5194/nhess-9-365-2009.
Full textAbstract:
Abstract. Terrestrial laser scanning (TLS) is one of the most promising surveying techniques for rockslope characterization and monitoring. Landslide and rockfall movements can be detected by means of comparison of sequential scans. One of the most pressing challenges of natural hazards is combined temporal and spatial prediction of rockfall. An outdoor experiment was performed to ascertain whether the TLS instrumental error is small enough to enable detection of precursory displacements of millimetric magnitude. This consists of a known displacement of three objects relative to a stable surface. Results show that millimetric changes cannot be detected by the analysis of the unprocessed datasets. Displacement measurement are improved considerably by applying Nearest Neighbour (NN) averaging, which reduces the error (1σ) up to a factor of 6. This technique was applied to displacements prior to the April 2007 rockfall event at Castellfollit de la Roca, Spain. The maximum precursory displacement measured was 45 mm, approximately 2.5 times the standard deviation of the model comparison, hampering the distinction between actual displacement and instrumental error using conventional methodologies. Encouragingly, the precursory displacement was clearly detected by applying the NN averaging method. These results show that millimetric displacements prior to failure can be detected using TLS.
38
Zhang, Xiaoshuang, Xiuchuan Zhang, and Yunshan Han. "A Case Study on Field Monitoring Analysis of Deep Foundation Pit in Soft Soils." Advances in Civil Engineering 2019 (May 2, 2019): 1–10. http://dx.doi.org/10.1155/2019/9342341.
Full textAbstract:
Field monitoring in the process of excavation of foundation pit is an important measure to reduce the risk. This paper describes a case study of the filed monitoring data during the process of deep foundation pit excavation in soft soil areas. The displacements of the diaphragm wall top were analysed and found that the horizontal displacement showed the convex shape, while the vertical displacement showed the concave shape. Based on the field monitoring data, the deformation mode of lateral displacement of the diaphragm wall belonged to the composite mode. The relationship between maximum lateral displacement and excavation depth showed a strong linear correlation. The horizontal displacements of bracing pillar decreased with the increasing of bracing stiffness, while the effect of bracing stiffness on vertical displacements of bracing pillar could be ignored. The settlement profile computed using the method of Hsieh and Ou was in good agreement with the field observations and better described the development trend of the ground surface settlement. The ratio of the maximum ground surface settlement (δvm) to the maximum lateral displacement of the diaphragm wall (δhm) was in the range of 0.74∼0.88, belonging to the range of 0.5∼1.0 proposed by Hsieh and Ou. This paper provides a reference basis and related guidance for similar projects.
39
Lee, H. M., Y. H. Kwon, Hyo Seon Park, and I. Lee. "Displacement Measurement of an Existing Long Span Steel Box-Girder Using Terrestrial Laser Scanning." Key Engineering Materials 347 (September 2007): 511–16. http://dx.doi.org/10.4028/www.scientific.net/kem.347.511.
Full textAbstract:
To make use of a new technology in the field of structural health monitoring, various displacement measuring techniques such as a global positioning system (GPS) and vision-based techniques have been studied and proposed. It was previously introduced a new displacement measuring technique using terrestrial laser scanning (TLS) that remotely samples the surface of an object using laser pulses and generates the three-dimensional (3D) coordinates of numerous points on the surface. In this paper, for an assessment of the capabilities of the measuring technique about existing structures, the field tests for vertical displacement measurement of an existing long span steel box-girder are experimentally carried out. The performance of the technique is evaluated by comparing the displacements obtained from TLS system and displacements directly measured from linear variable displacement transducer (LVDT).
40
Juozapaitis, Algirdas, and Arnoldas Norkus. "SHAPE DETERMINING OF A LOADED CABLE VIA TOTAL DISPLACEMENTS." Technological and Economic Development of Economy 11, no. 4 (December 31, 2005): 283–91. http://dx.doi.org/10.3846/13928619.2005.9637709.
Full textAbstract:
Cable structures are very efficient (in economic aspect) when applied to cover large spans. The cable structure consists of a single cable or a network of cables. The cable attractive feature is the highest ratio of strength to weight amongst other carrying structural elements, usually applied in engineering practice. But a cable is a specific structural element able to response only one type of deforming ‐ tension (flexural rigidity actually vanishes). Therefore, when loaded a cable shapes the form to resist tension only. This adaptation is followed by large nonlinear displacements. Thus, the nature of geometrical nonlinear cable behavior is quitie a different from that of rigid structural elements. Both elements response via small deformations when loaded, but large displacements of a cable are conditioned by its adaptation to loading, and those of rigid structural elements ‐ by actual deformations. One can also note that deformations of a cable are significantly less than those of rigid structural elements, but at the same time actual cable displacements are significantly larger. Thus, the main disadvantage of a cable structure is its response to loading by large displacements caused by asymmetric loading component (usually met in engineering practice, e.g. the design of suspension bridges, coverings of stadium, etc). Therefore stiffness conditions predominate in the actual codified cable design. Having identified governing factors conditioning displacement magnitudes one can introduce the constructional means/solutions assigned to reduce them if required. Therefore the evaluation of cable displacements by a reliable and sufficiently exact method compatible with the calculation of actual engineering structures is under current necessity. When analyzing total displacements the principle of superposition is employed in a special sequence. Total displacement is split into two components: kinematic and elastic. The first component represents cable form shaping the loading, the second one is conditioned by elastic deformations. Any point displacement of an asymmetrically loaded cable can be expressed via its middle span. The developed analytical expressions to evaluate middle span displacements are presented. They enable to identify maximal displacements and their locations. The developed analytical method for total displacements evaluation is tested numerically. The comparative analysis in respect of the influence of various parameters conditioning displacement magnitudes is performed. The displacement evaluation errors, their causality conditioned by the application of approximate‐ widely applied engineering methods, are discussed.
41
Minkevich, A. A., M. Köhl, S. Escoubas, O. Thomas, and T. Baumbach. "Retrieval of the atomic displacements in the crystal from the coherent X-ray diffraction pattern." Journal of Synchrotron Radiation 21, no. 4 (June 3, 2014): 774–83. http://dx.doi.org/10.1107/s1600577514010108.
Full textAbstract:
The retrieval of spatially resolved atomic displacements is investigatedviathe phases of the direct(real)-space image reconstructed from the strained crystal's coherent X-ray diffraction pattern. It is demonstrated that limiting the spatial variation of the first- and second-order spatial displacement derivatives improves convergence of the iterative phase-retrieval algorithm for displacements reconstructions to the true solution. This approach is exploited to retrieve the displacement in a periodic array of silicon lines isolated by silicon dioxide filled trenches.
42
Campbell, Bruce T., and Franklin M. Orr. "Flow Visualization for CO2/Crude-Oil Displacements." Society of Petroleum Engineers Journal 25, no. 05 (October 1, 1985): 665–78. http://dx.doi.org/10.2118/11958-pa.
Full textAbstract:
Abstract Results of visual observations of high-pressure CO2 floods are reported. The displacements were performed in two-dimensional (2D) pore networks etched in glass plates. Results of secondary and tertiary first-contact miscible displacements and secondary and tertiary multiple-contact miscible displacements are compared. Three displacements with no water present were performed in each of three pore networks:displacement of a refined oil by the same oil dyed a different color;displacement of a refined oil by CO2 (first-contact miscible); anddisplacement of a crude oil at a pressure above the minimum miscibility pressure. In addition, three tertiary displacements were performed in the same pore networks;displacement of the refined oil by water, followed by displacement by the same refined oil dyed to distinguish it from the original oil;tertiary displacement of the refined oil by CO2; andtertiary displacement of crude oil by CO2. In addition, recovery of oil from dead-end pores, with and without water barriers shielding the oil, was investigated. Visual observations of pore-level displacement events indicate that CO2 displaced oil much more efficiently in both first-contact and multiple-contact miscible displacements when water was absent. In tertiary displacements of a refined oil, CO2 effectively displaced the oil it contacted, but high water saturations restricted access of CO2 to the oil. The low viscosity of CO2 aggravated effects of high water saturations because the CO2 did not displace water efficiently. CO2 did, however, contact trapped oil by diffusing through water to reach, to swell, and to reconnect isolated droplets. Finally, CO2 displaced crude oil more efficiently than it did the refined oil in tertiary displacements. Differences in wetting behavior between the refined and crude oils appear to account for the different flow behavior. Introduction If high-pressure CO2 displaces oil in a one-dimensional (1D), uniform porous medium (in which the effects of viscous fingering are necessarily absent), the displacement efficiency is controlled by the phase behavior of the CO2/crude-oil mixtures. The conventional description of the effects of phase behavior was given by Hutchinson and Braun1 for vaporizing gas drives and was extended to CO2 systems by Rathmell et al.2 In a rigorous mathematical treatment of the flow of three-component mixtures. Helfferich3 proved that the displacement will develop miscibility if the oil composition lies outside the region of tie-line extensions on a ternary diagram. Helfferich's analysis was for 1D flows in which fluids are mixed well locally, and the effects of dispersion are absent. Sigmund et al.,4 Gardner et al.,5 and Orr et al.6 showed that results of slim-tube displacements, which are nearly 1D and come close to eliminating the effects of viscous instability, can be predicted quantitatively by 1D process simulations based on independent measurements of the phase behavior and fluid properties of the CO2/crude-oil mixtures. Thus there is good experimental confirmation that the simple theory of the effects of phase behavior on displacement performance describes accurately the behavior of flow in an ideal displacement, such as a slim tube. In a CO2 flood in reservoir rock, however, a variety of other factors will influence process performance. Because the viscosity CO2 is much lower than that of most oils, viscous instability will limit the sweep efficiency of the injected CO2. In addition, Gardner and Ypma7 predicted, based on 2D simulations of the growth of a viscous finger, that an interaction between viscous instability and phase behavior would lead to higher residual oil saturation in regions penetrated by a viscous finger. Pore-structure heterogeneity may also influence displacement efficiency. Spence and Watkins8 found that residual oil saturations after CO2 waterfloods increased as the heterogeneity of the core increased. Several investigators have reported that high water saturations can alter mixing between oil and injected solvent. Raimondi and Torcaso9 found, in displacements in Berea sandstone cores, that significant fractions of the oil phase could not be contacted by injected solvent when the water saturation was high. Thomas et al.10 reported that a portion of the nonwetting phase can exist in "dendritic" pores whose shapes were determined by the surrounding wetting phase. They argued that material in the dendritic pores mixed with fluid in the flowing fraction only by diffusion. Stalkup11 and Shelton and Schneider12 also investigated effects of mobile water saturations in miscible displacements. Stalkup found that the flowing fraction decreased as the water saturation increased. Shelton and Schneider reported that the presence of a second mobile phase slowed recovery of either phase, but the nonwetting phase was affected more strongly. In their tests, all of the wetting phase was recovered by a miscible displacement, but significant amounts of nonwetting phase remained unrecovered.
43
Han, Park, Park, Kim, and Baek. "Experimental Verification of Methods for Converting Acceleration Data in High-Rise Buildings into Displacement Data by Shaking Table Test." Applied Sciences 9, no. 8 (April 21, 2019): 1653. http://dx.doi.org/10.3390/app9081653.
Full textAbstract:
When diagnosing damage to high-rise buildings during earthquakes, it is necessary to measure the displacement of each story. However, with respect to accuracy and cost, it is most reasonable to convert acceleration into displacement. In this study, shake table testing was carried out to verify the conversion methods, converting the acceleration data measured in a high-rise building into velocity and displacement. In the shaking table test, the displacement of a 10-story model building under strong motion was measured using high-speed imaging devices. High-speed images were taken at 1000 frames per second, reflecting the dynamic behavior of the model building. Then, this displacement was compared with the displacement obtained by processing the acceleration data. This study applied three methods for correcting and converting acceleration into velocity and displacement. Method 1 used the transfer function, H2ω, which reflects the dynamic characteristics of the system. The displacements converted by this method showed the lowest accuracy, because the transfer function depends on the dynamic characteristics of the structure. Method 2 used the cosine Fourier transform for baseline correction, and the discrete input data are calculated as the sum of the cosine functions. Method 3 used the least-squares fitting in the first step to remove the linear drift in the acceleration and applied the high-pass Butterworth filter. The displacements converted by Method 2 were the most reliable, and were close to the displacements measured in the shaking table test. However, the response of high-rise buildings is affected by low- and high-frequency noise. It is necessary to further investigate the limitations and applicability of the conversion methods for providing reliable displacement of the building.
44
Yang, Xue-Min, and Paul M. Davis. "Deformation due to a rectangular tension crack in an elastic half-space." Bulletin of the Seismological Society of America 76, no. 3 (June 1, 1986): 865–81. http://dx.doi.org/10.1785/bssa0760030865.
Full textAbstract:
Abstract Closed, analytic expressions are given for the displacement fields, their derivatives, and stresses from a rectangular crack in an elastic half-space having Burger's vector normal to its surface. Displacements are found by integration of Volterra's formula over the crack area using Mindlin's (1936) point force solutions for the elastic half-space. Differentiation of the displacement fields yields expressions for calculating stress and strain throughout the medium. Contours of stresses and displacements are given for selected geometries. The expressions for displacements give identical values to those calculated using angular dislocations (Comninou and Dundurs, 1975). All solutions are presented as a FORTRAN subroutine to facilitate practical implementation.
45
Wei, Lianhuan, Qiuyue Feng, Feiyue Liu, Yachun Mao, Shanjun Liu, Tianhong Yang, Cristiano Tolomei, Christian Bignami, and Lixin Wu. "Precise Topographic Model Assisted Slope Displacement Retrieval from Small Baseline Subsets Results: Case Study over a High and Steep Mining Slope." Sensors 20, no. 22 (November 21, 2020): 6674. http://dx.doi.org/10.3390/s20226674.
Full textAbstract:
Due to the intrinsic side-looking geometry of synthetic aperture radar (SAR), time series interferometric SAR is only able to monitor displacements in line-of-sight (LOS) direction, which limits the accuracy of displacement measurement in landslide monitoring. This is because the LOS displacement is only a three dimensional projection of real displacement of a certain ground object. Targeting at this problem, a precise digital elevation model (DEM) assisted slope displacement retrieval method is proposed and applied to a case study over the high and steep slope of the Dagushan open pit mine. In the case study, the precise DEM generated by laser scanning is first used to minimize topographic residuals in small baseline subsets analysis. Then, the LOS displacements are converted to slope direction with assistance of the precise DEM. By comparing with ground measurements, relative root mean square errors (RMSE) of the estimated slope displacements reach approximately 12–13% for the ascending orbit, and 5.4–9.2% for the descending orbit in our study area. In order to validate the experimental results, comparison with microseism monitoring results is also conducted. Moreover, both results have found that the largest slope displacements occur on the slope part, with elevations varying from −138 m to −210 m, which corresponds to the landslide area. Moreover, there is a certain correlation with precipitation, as revealed by the displacement time series. The outcome of this article shows that rock mass structure, lithology, and precipitation are main factors affecting the stability of high and steep mining slopes.
46
Zhu, Hong Hu, Jian Hua Yin, Hua Fu Pei, Lin Zhang, and Wei Shen Zhu. "Fiber Optic Displacement Monitoring in Laboratory Physical Model Testing." Advanced Materials Research 143-144 (October 2010): 1081–85. http://dx.doi.org/10.4028/www.scientific.net/amr.143-144.1081.
Full textAbstract:
For physical models, conventional techniques have difficulties in monitoring internal displacements during laboratory testing. In this paper, based on fiber Bragg grating (FBG) sensing technology, a bar-type fiber optic displacement sensor is developed for small-scale models. When the model deforms due to loading or unloading, the embedded displacement sensor can capture the displacement profile along the bar length using the strain data from quasi-distributed FBGs. Laboratory calibration tests have showed that the displacements measured by the FBG sensing bar are in good agreement with those from conventional displacement transducers. For the physical models of a gravity dam and a cavern group, the FBG sensing bars were successfully installed in predefined holes, together with conventional gauges. During testing, the FBG sensing bars measured the displacement distributions within the models. The fiber optic monitoring results demonstrate the deformation characteristics of surrounding rock masses induced by overloading and underground excavation and indicate the overall stability conditions of these two geo-structures.
47
Jurkonis, Rytis, Monika Makūnaitė, Mindaugas Baranauskas, Arūnas Lukoševičius, Andrius Sakalauskas, Vaidas Matijošaitis, and Daiva Rastenytė. "Quantification of Endogenous Brain Tissue Displacement Imaging by Radiofrequency Ultrasound." Diagnostics 10, no. 2 (January 21, 2020): 57. http://dx.doi.org/10.3390/diagnostics10020057.
Full textAbstract:
The purpose of this paper is a quantification of displacement parameters used in the imaging of brain tissue endogenous motion using ultrasonic radiofrequency (RF) signals. In a preclinical study, an ultrasonic diagnostic system with RF output was equipped with dedicated signal processing software and subject head–ultrasonic transducer stabilization. This allowed the use of RF scanning frames for the calculation of micrometer-range displacements, excluding sonographer-induced motions. Analysis of quantitative displacement estimates in dynamical phantom experiments showed that displacements of 55 µm down to 2 µm were quantified as confident according to Pearson correlation between signal fragments (minimum p ≤ 0.001). The same algorithm and scanning hardware were used in experiments and clinical imaging which allows translating phantom results to Alzheimer’s disease patients and healthy elderly subjects as examples. The confident quantitative displacement waveforms of six in vivo heart-cycle episodes ranged from 8 µm up to 263 µm (Pearson correlation p ≤ 0.01). Displacement time sequences showed promising possibilities to evaluate the morphology of endogenous displacement signals at each point of the scanning plane, while displacement maps—regional distribution of displacement parameters—were essential for tissue characterization.
48
GRISO, GEORGES. "ASYMPTOTIC BEHAVIOR OF STRUCTURES MADE OF CURVED RODS." Analysis and Applications 06, no. 01 (January 2008): 11–22. http://dx.doi.org/10.1142/s0219530508001031.
Full textAbstract:
In this paper, we study the asymptotic behavior of a structure made of curved rods of thickness 2δ when δ tends to 0. This study is carried on within the frame of linear elasticity by using the unfolding method. It is based on several decompositions of the structure displacements and on the passing to the limit in fixed domains. We show that any displacement of a structure is the sum of an elementary rods-structure displacement (e.r.s.d.) concerning the rods' cross sections and a residual one related to the deformation of the cross section. The e.r.s.d. coincides with rigid body displacements in the junctions. Any e.r.s.d. is given by two functions belonging to [Formula: see text] where [Formula: see text] is the skeleton structure (i.e. the set of rods with middle lines). One of this function [Formula: see text] is the skeleton displacement, the other [Formula: see text] gives the cross section rotation. We show that [Formula: see text] is the sum of an extensional displacement and an inextensional one. We establish a priori estimates and then, we characterize the unfolded limits of the rods-structure displacements. Eventually, we pass to the limit in the linearized elasticity system and using all results in [6], where on one hand, we obtain a variational problem that is satisfied by the limit extensional displacement, and on the other hand, a variational problem coupling the limit of inextensional displacement and the limit of the rod torsion angles.
49
Chen, Hao, and Tomy Varghese. "Noise analysis and improvement of displacement vector estimation from angular displacements." Medical Physics 35, no. 5 (April 25, 2008): 2007–17. http://dx.doi.org/10.1118/1.2905024.
Full text
50
Shpeĭzman, V. V., and N. N. Peschanskaya. "Interferometric measurement of displacements and displacement velocities for nondestructive quality control." Physics of the Solid State 49, no. 7 (July 2007): 1259–63. http://dx.doi.org/10.1134/s1063783407070104.
Full text