Displacement Analysis Research Articles

Special Feature: Putting urban displacement in its place

This paper offers a critical analysis of urban displacement and acts as an introduction to the Special Feature: ‘Putting urban displacement in its place’. It begins by noting the magnitude and significance of displacement, and summarises its constituent components. Drawing upon the work of Hirsh, Eizenberg and Jabareen [2020. “A New Conceptual Framework for Understanding Displacement: Bridging the Gaps in Displacement Literature between the Global South and the Global North.” Journal of Planning Literature 35 (4): 391–407], the paper then outlines four kinds of urban displacement processes which span cities in the Global South and North: development-induced displacement, slum clearance, eviction, and gentrification. Brief consideration is also given to the significance of studentification, touristification, and austerity for driving urban displacement. Next the paper explores three crucial issues regarding the conceptualisation of urban displacement: temporality, vulnerability to displacement, and its emotional impacts. The following section discusses rehousing/resettlement and post-displacement experiences. We then examine the contested relationship between displacement and gentrification. The penultimate section outlines some of the methodological challenges in undertaking research on displacement, and also returns to the theme of placing urban displacement via a discussion of urban politics. The final section summarises the four papers in the Special Feature.

The refusal of the migrant in Ala Eddine Slim’s The Last of Us

Chris Lippard’s analysis of displacement and refusal in the Tunisian film, The Last of Us (Akher wahad fina), rearticulates the cinematic quest for an aesthetic means by which to express the refusal of migrant positionality. Taking a rhetorically performative approach, he suggests both the possibilities and pitfalls inherent in different forms of displacement, including disappearance and disassembly, as a means of refuting postcolonial categories and conceptions of migration. The film offers an opportunity for considering alternative aesthetics within the contemporary depiction of migration, and one for questioning the tropes of migration narratives in an imagined decolonized space where modernity and commoditization have not taken hold and an alternative migration journey is thus depicted: one that differently incorporates the experience of being other(ed) with which migration narratives have constantly to engage, though also one that, in its separation from national and transnational networks, risks a retreat into immanence.

Displacement analysis of a geogrid-reinforced retaining wall with modular precast concrete facing

Reinforced earth retaining walls are widely used in transportation projects, such as embankments, bridge access roads, and bridge abutments. When the wall height is large, the weight of the embankment soil and vehicle loads can cause large wall displacements, thereby affecting the serviceability of the wall system. Although many retaining wall projects use wall-facing structures assembled from precast concrete components, most domestic studies have focused on continuous reinforced concrete wall-facing structures. Therefore, to understand the displacement behavior of reinforced retaining walls when the wall height is large, we investigated the displacement behavior of an earth retaining wall in the My Phuoc-Tan Van overpass project, Binh Duong Province. This study uses a finite element simulation that considers the nonlinear behavior of backfill soil, foundation soil, geotextiles, and the interaction between precast concrete units.

Structural Characteristics of Steel Pipe Piles Using CLSM

Recently, as underground construction becomes larger and deeper, temporary facilities must be designed, and methods suitable for the construction environment, such as the shape of surrounding structures and ground conditions, must be applied. Among them, the importance of self-contained earth retaining wall temporary facility construction is growing. Therefore, the installation method and construction technology of the self-contained earth retaining wall temporary facility structure must be improved. In this study, to evaluate the structural behavior of steel pipe piles for self-contained earth retaining wall, a full-scale specimen was fabricated, the steel pipe ends were welded with round steel plates, and CLSM was filled through the sand compaction inside the steel pipe. Subsequently, compressive and flexural strength tests were conducted on the specimen in which both ends of the steel pipe were welded with round steel plates. Additionally, a finite element analysis of the vertical displacement of the bending specimen according to the load was performed based on the results from the ANSYS finite element analysis, and the results were compared.

Surfactant-like Additives Assisted the Lateral Growth of Pentacene Films.

Lateral growth of thin films is crucial for organic electronic devices, such as field-effect transistors. Here, we report a strategy to improve the lateral growth of pentacene films using rubrene as a surfactant-like additive. Atomic force microscopy (AFM) images confirm the enhanced lateral growth with the presence of rubrene, resulting in smooth and enlarged molecule domains in the films in comparison to those without rubrene. Molecular dynamics simulations are conducted to explore the interlayer diffusion of pentacene molecules during the growth. With the rubrene molecules as surfactant-like additives, mean square displacement (MSD) analysis shows that the pentacene molecules have a descending diffusion coefficient of 2.0 × 10-5 cm2 s-1, which is greater than the ascending diffusion coefficient of 1.6 × 10-5 cm2 s-1. The more descending molecules lead to an enhanced lateral growth of pentacene films, which is in good agreement with the experiments. As a result, the pentacene films grown with rubrene exhibit a rapid increase in carrier mobility over thickness due to the well-connected domains resulting from enhanced lateral growth. This finding will provide a new strategy to modulate the morphology of organic films for high-performance devices.

Numerical simulation of proton backscattering spectra in GEANT4 toolkit

Rutherford backscattering spectroscopy (RBS) is a widely used technique for the atomic-scale analysis of sample composition, lattice displacement and impurity profiling. RBS is based on the elastic scattering of incident charged particles by target nuclei and the subsequent detection of scattered particles. The interpretation of RBS spectra, however, poses challenges due to overlapping peaks, corresponding to scattering from different atomic species, and uncertainties from energy loss, scattering geometry and detector response. To address this, an open source simulation model based on the versatile GEANT4 simulation toolkit has been developed. The flexibility of the open source enables users to tailor the model to its specific requirements, such as the use of specific particle stopping powers, cross-sections, and physics processes. This work presents the results of the comparison between the experimental and simulated backscattering spectra in crystalline silicon, silicon carbide and silicon dioxide samples by 1–2.5 MeV energy protons, obtained in random orientation conditions. The results demonstrate the capability of the model to accurately simulate backscattering spectra in both amorphous materials and single crystals. The overall agreement between the simulated and experimental results is highly promising for future development and use in the interpretation and simulation of RBS spectra.

Modal displacement analyses of Lamb waves in micro/nano-plates based on the consistent couple stress theory

In micro-scale structures, the influence of scale effects on the mechanical properties cannot be ignored, and the continuum mechanics theory cannot effectively describe guided wave propagation. This paper studies modal displacements in an isotropic micro/nano-scale plate — an essential factor for the mode selection of Lamb waves in non-destructive testing technology. To achieve this, the consistent couple stress theory, which additionally accounts for the impact of scale effects on wave propagation, has to be employed. A mathematical derivation method with singular value decomposition is proposed, and the excitation amplitude is computed by applying a normal stress source to evaluate the in-plane and out-of-plane displacements. The results indicate that the in-plane displacement vanishes on the plate surface for anti-symmetric modes when the phase velocity equals the velocity of shear waves. Moreover, the intersections of symmetric and anti-symmetric dispersion curves identify specific frequencies at which the out-of-plane displacement vanishes on the free surface. These findings highlight the difference in modal displacement characteristics between micro-scale and macro-scale structures. The results from this study may furnish theoretical guidance for ultrasonic non-destructive testing of microstructures.

Multidimensional displacement analysis of Semeru Volcano, Indonesia following December 2021 eruption from multitrack InSAR observation

Multidimensional displacement analysis of Semeru Volcano, Indonesia following December 2021 eruption from multitrack InSAR observation

Displacement and damage analysis of earth dams during the 2023 Turkiye earthquake sequence

The earthquake sequence that occurred on 6 February 2023 in Turkiye caused significant damage to various infrastructures including geostructures such as dams. A total of 17 earth dams within a 200-km radius of the earthquake epicenter experienced varying degrees of damage, ranging from minor (∼2 cm) to major (up to ∼150 cm) deformations. As study of these reveals that the damaged dams are located within the closest distance to the fault of less than 30 km, with an average value of ∼12 km. This study specifically focuses on the seismic displacement analysis of the 17 damaged dams, utilizing the sliding block methods. The recorded motion data was analyzed using the kriging technique to estimate the spectral response at the dam sites. Moreover, the recorded ground motions were scaled to the resonant period of the dam site to estimate acceleration time history. The findings reveal that the rigid block analysis can provide an average estimation of seismic displacement with a relative error of less than 44%. The results of the damage analysis indicate that seven dams reached the ultimate limit state and two dams experienced the serviceability limit state. Moreover, the univariate and multivariate fragility functions are developed to estimate seismic probabilistic analysis of earth dams based on the observed data and the limit states. The results show that the selection of a single intensity measure (IM) and a combination of IMs can affect the predicted probability of failure. The findings provide an insight into the resilience assessment of dams and other geosystems during this strong earthquake.

Enhancing Structural Resilience: A Comparative Study of G+35 Storey Irregular Buildings with Bracing and Diagrid Systems

Abstract: The study presented herein delves into the structural performance and behavior of a building subjected to different configurations, namely, an Irregular Building, an Irregular Building with Steel Bracing, and an Irregular Building with Diagrid System. The focus of the investigation is on key structural parameters such as node displacements and storey shear values across various levels of the building. Understanding how these parameters vary in response to different design strategies is vital for assessing the overall stability, safety, and efficiency of the structure in the face of external forces. Structural engineers and designers are constantly striving to optimize building designs to meet safety standards and performance criteria. The incorporation of additional elements, such as steel bracing or a diagrid system, can significantly impact a structure's ability to withstand lateral forces, ensuring resilience in the face of dynamic loads such as wind or seismic events. By comparing the performance of the three configurations, this study aims to provide insights into the efficacy of these design strategies and their influence on key structural indicators. Through a comprehensive analysis of node displacements and storey shear values at various levels, this study seeks to contribute valuable information to the field of structural engineering. The findings may inform future design decisions, guide improvements in structural systems, and enhance the understanding of how different configurations influence the overall behavior of a building. Ultimately, the knowledge gained from this study can contribute to the advancement of resilient and efficient structural designs, with implications for the broader fields of architecture and civil engineering.

Displacement analysis of the October 30, 2020 (M w = 6.9), Samos (Aegean Sea) earthquake

Abstract Destructive earthquakes with high deformations have occurred in the Aegean region since the historical period. The most destructive of these earthquakes in recent years is the October 30, 2020 (M w = 6.9) Samos (Aegean Sea) earthquake. This earthquake affected a wide area and caused numerous losses of lives and property especially in Izmir city. For examining the effects of the earthquake, Global Navigation Satellite System (GNSS) data before, during, and after the earthquake were processed, and coseismic and postseismic displacement evaluations were made. Interferometric Synthetic Aperture Radar (InSAR) ascending, descending interferograms, line of sight velocity, and displacement maps were obtained for the earthquake-affected area. The GNSS and InSAR data were evaluated together, and the areas with subsidence and uplift were determined in conjunction with the fault zone. In addition, the horizontal displacements were analyzed by using Coulomb failure criteria, and peak ground displacements were obtained from the strong motion stations located in the study region. As a result, from all the displacement analyses, it was determined that high-amplitude energy was released, at the regional scale from Ayvalık in the North to Datça in the South after the earthquake, and this earthquake generated permanent deformation in the affected region.

Fracture analysis of orthotropic functionally graded materials using element-based peridynamics

A fracture model of orthotropic functionally graded materials (FGMs) based on element-based peridynamics (EBPD) is proposed. Two-dimensional (2D) orthotropic FGMs use three-node triangular elements to describe the force density of EBPD. Due to the gradient difference of material properties inside the element, the Gauss integral formula is used to average the node performances to the integral point of the element. The equations of motion for EBPD is established, which is also applied to orthotropic FGMs by the Gauss integral formula. The micromodulus coefficient of the EBPD is derived for orthotropic FGMs. The critical strain energy density criterion is used as the failure criterion to simulate the quasi-static and dynamic fracture problems. A series of numerical examples, including displacement analysis, stress analysis, dynamic crack propagation of FGM beam, and crack growth of orthotropic FGMs under four-point bending load, are used to validate the accuracy of the fracture model of orthotropic FGMs. The proposed model can be helpful to the material gradient design for FGMs satisfying certain requirements.

Layering Ni to mediate the Kirkendall effect (KE) in cu/ta nonequilibrium diffusion for enhanced abrasion resistance

This study delves into the KE occurring at the interface of the Cu/Ta system during thermal diffusion, along with the mediating impact of integrating a Ni interlayer on the nonequilibrium diffusion of Cu/Ta. In the Cu/Ta system, nonequilibrium thermal diffusion results in the generation and aggregation of Cu side Kirkendall voids (KVs). In the Cu/Ni/Ta system, the Ni interlayer ensures the equilibrium of system atom migration through the movement and annihilation of vacancies, thereby enhancing the bonding between the layers. Calculations of interdiffusion coefficients using the Boltzmann-Matano (B-M) method reveal that interdiffusion coefficients at the coating-substrate interface are 4–5 orders of magnitude higher for the Cu/Ta system compared to the Cu/Ni/Ta system. The analysis of mean square displacement (MSD) and radial distribution function (RDF) provides insights into the role of the Ni interlayer as a potential barrier mediating the atomic-level diffusion behavior of the system. Moreover, the Cu/Ni coating exhibits superior abrasion resistance and bond strength compared to the Cu coating, attributed to the inhibition of KVs generation at the interface. This exploration introduces a novel approach to inhibit defects stemming from the KE and advances comprehension of interfacial phenomena in composites.

Depletion of the m1A writer TRMT6/TRMT61A reduces proliferation and resistance against cellular stress in bladder cancer.

Bladder cancer (BLCA) is a common and deadly disease that results in a reduced quality of life for the patients and a significant economic burden on society. A better understanding of tumorigenesis is needed to improve clinical outcomes. Recent evidence places the RNA modification m1A and its regulatory proteins TRMT6/TRMT61A and ALKBH3 in BLCA pathogenesis. TRMT6/TRMT61A, ALKBH1, and ALKBH3 expression was examined in human BLCA cell lines and a normal urinary tract epithelium cell line through qRT-PCR and western blot analysis. Prestoblue Cell Viability Reagent, wound-healing assay, and live-cell imaging-based cell displacement analysis, were conducted to assess proliferation, migration, and displacement of this BLCA cell line panel. Cell survival was assessed after inducing cellular stress and activating the unfolded protein response (UPR) with tunicamycin. Moreover, siRNA-mediated gene silencing in two BLCA cell lines (5637 and HT1197) was conducted to investigate the biological roles of TRMT6/TRMT61A. Heterogeneous morphology, proliferation, displacement, tunicamycin sensitivity, and expression levels of m1A regulators were observed among the panel of cell lines examined. In general, TRMT61A expression was increased in BLCA cell lines when compared to SV-HUC-1. Depletion of TRMT6/TRMT61A reduced proliferation capacity in both 5637 and HT1197 cell lines. The average cell displacement of 5637 was also reduced upon TRMT6/TRMT61A depletion. Interestingly, TRMT6/TRMT61A depletion decreased mRNA expression of targets associated with the ATF6-branch of the UPR in 5637 but not in HT1197. Moreover, cell survival after induction of cellular stress was compromised after TRMT6/TRMT61A knockdown in 5637 but not in HT1197 cells. The findings suggest that TRMT6/TRMT61A plays an oncogenic role in BLCA and is involved in desensitizing BLCA cells against cellular stress. Further investigation into the regulation of TRMT6/TRMT61A expression and its impact on cellular stress tolerance may provide insights for future BLCA treatment.

Investigating paleoseismicity using high-resolution airborne LiDAR data - A case study of the Huangxianggou fault in the northeastern Tibetan plateau

Fault-offset landforms have long been recognized as holding important information about paleoseismic slip. Constructing an along-strike fault slip distribution could help reveal a fault's long-term rupture patterns and facilitate a more precise assessment of its future behavior. In this study, we documented the paleoseismic history of the Huangxianggou Fault, an oblique sinistral-thrust segment of the West Qingling Fault in the northeastern region of the Tibetan Plateau, using LiDAR-derived high-resolution DEM (0.1 m/pixel) and measurement of offset landforms. A total of 46 well-preserved and well-shaped landforms were chosen for horizontal and vertical displacement measurements, and the dense measurement data allow us to generate the cumulative offset probability distribution curves of horizontal and vertical displacements. Statistical analysis revealed at least seven surface-rupturing events, each with similar coseismic horizontal displacements of ∼7.0 m and vertical displacements of ∼0.7 m, in agreement with previous paleoseismic trench results. Using empirical relationships between moment magnitude and horizontal displacement, a plausible moment magnitude range of Mw7.3–7.7 was determined for these paleoearthquakes. Furthermore, by evaluating rupture parameters and fault slip rate, we determined a recurrence interval of 2.7–3.4 kyr for significant surface-rupturing events on this fault. The elapsed time since the last earthquake closely approaches this interval, suggesting a potential seismic risk for the Huangxianggou Fault. Our results emphasizes the importance of high-resolution topographic data in paleoseismic investigations, enabling the identification of numerous offset landforms and precise displacement measurements across faults. Paleoearthquake counts derived from horizontal and vertical displacement analyses were found to be consistent, highlighting the significance of vertical displacements in quantifying paleoearthquakes for strike-slip faults with a thrust component.

An enhanced corotational Virtual Element Method for large displacements in plane elasticity

An enhanced virtual element formulation for large displacement analyses is presented. Relying on the corotational approach, the nonlinear geometric effects are introduced by assuming nodal large displacements but small strains in the element. The element deformable behavior is analyzed with reference to the local system, corotating with the element during its motion. Then, the large displacement-induced nonlinearity is accounted for through the transformation matrices relating the local and global quantities. At the local level, the Virtual Element Method is adopted, proposing an enhanced procedure for strain interpolation within the element. The reliability of the proposed approach is explored through several benchmark tests by comparing the results with those evaluated by standard virtual elements, finite element formulations, and analytical solutions. The results prove that: (i) the corotational formulation can be efficiently used within the virtual element framework to account for geometric nonlinearity in the presence of large displacements and small strains; (ii) the adoption of enhanced polynomial approximation for the strain field in the virtual element avoids, in many cases, the need for ad-hoc stabilization procedures also in the nonlinear geometric framework.

An artistic perspective on individual space–time flows

ABSTRACT Cartographically, there are now many ways of depicting the spatiotemporal life of human individuals, from flow and animated maps to 3D space-time cubes. However, these scientifically led representations have limited expressive potential for the emotional and inner life of these individuals. Artistic visual forms have been identified as a resource to bring such qualitative communication to and alongside maps. In the ‘Journey as a Flow' project we attempt to represent the geometry and motivation of everyday human motion in relation to various points in the environment and within an environment of other individual flows. We have produced various visual artwork sketches in order to understand the wide range of environmental flows of an individual as well as one's perception of them. We used the space-time cube (i.e. time-geographic aquarium) as a starting point, dictated by the need to create a functional tool in which space and time were both visible, as well as having potential as a 3D tangible object for physical exhibition. This forms the basis for analyses of displacement, interaction and perception. All the modifications of this established geospatial visualisation are inspirations and incorporations from art disciplines. The project outputs therefore include inspirations from cine-plastic art and Escher’s perspective drawings, but the main part of it draws from the Italian renaissance concept of the image conceived as a framed window through which we look at the world. The idea of central perspective has also been used to portray spaces as a flow toward a specific destination. The overall set of representations depict a dynamic version of human lives, while the set of various metaphors deployed drive an artistic interpretation of how some people can perceive (their own / other) flows during their journey. A transformation has therefore occurred from a temporal flow would be conventionally spatial to one that assumes platial properties (i.e. an individually led geography of place).

Digital image correlation techniques for motion analysis and biomechanical characterization of plants.

Temporally and spatially complex 3D deformation processes appear in plants in a variety of ways and are difficult to quantify in detail by classical cinematographic methods. Furthermore, many biomechanical test methods, e.g. regarding compression or tension, result in quasi-2D deformations of the tested structure, which are very time-consuming to analyze manually regarding strain fields. In materials testing, the contact-free optical 2D- or 3D-digital image correlation method (2D/3D-DIC) is common practice for similar tasks, but is still rather seldom used in the fundamental biological sciences. The present review aims to highlight the possibilities of 2D/3D-DIC for the plant sciences. The equipment, software, and preparative prerequisites are introduced in detail and advantages and disadvantages are discussed. In addition to the analysis of wood and trees, where DIC has been used since the 1990s, this is demonstrated by numerous recent approaches in the contexts of parasite-host attachment, cactus joint biomechanics, fruit peel impact resistance, and slow as well as fast movement phenomena in cones and traps of carnivorous plants. Despite some technical and preparative efforts, DIC is a very powerful tool for full-field 2D/3D displacement and strain analyses of plant structures, which is suitable for numerous in-depth research questions in the fields of plant biomechanics and morphogenesis.

Liquefaction triggering and induced ground deformations at a metallurgical facility in Dörtyol-Hatay after the February 6 Kahramanmaraş earthquake sequence

The performance of a Metallurgical Facility located on the Dörtyol-Hatay coast is investigated from seismic soil liquefaction engineering perspective. The facility was shaken by the M7.8, and M7.6 Pazarcık and Ekinözü-Elbistan Kahramanmaraş earthquake sequence. This paper presents the assessment results of soil liquefaction triggering and induced ground deformations at the site. It discusses: i) the seismic response of the facility, more specifically, the surface manifestation of seismic soil liquefaction in the form of soil ejecta, ground deformations and displacements, mapped after the earthquake sequence, ii) the results of site investigation studies, performed prior to the events, iii) subsurface soil characterization of the site, iv) assessments of soil liquefaction triggering, v) analyses of liquefaction-induced ground settlements, lateral deformations and displacements, and vi) comparisons of them with those of the predicted. The case history performance documented herein, and the assessment results are believed to be useful in the development of case history-based predictive models for the assessment of liquefaction triggering and post-liquefaction ground deformations.

Assessment of seismic slope stability of Rangamati Hill Tracts, Bangladesh

Slope stability is an essential aspect of geotechnical engineering. Unstable slopes or stable slopes influenced by external factors may result in a catastrophic disaster called a landslide. In seismically active areas with steep terrain, landslides commonly occur and are regarded as one of the most severe threats. Bangladesh has not suffered any destructive earthquakes in recent years but has a considerable risk of facing such earthquakes owing to its geological conditions. Although slope failures occurring in the Rangamati Hill Tracts of Bangladesh are mainly rainfall-induced, due to the seismic risk in Bangladesh, it is essential to assess earthquake-induced slope failure in vulnerable areas. In this study, the authors analyzed the seismic slope stability at three locations in the Rangamati Hill Tracts using pseudostatic approaches. The pseudostatic approach with the variation in seismic force based on the seismic coefficient was utilized to determine the critical conditions. Using Newmark’s rigid block method, the permanent displacements for various slope conditions were calculated for the Kobe earthquake. The analysis provided crucial insight into the state of the locations. One location has a low factor of safety (FS) value at a slope angle of 30° or greater, whereas the others have a risk of slope failure at a slope angle of 50° or greater. Newmark’s displacement analysis also showed that the slopes at location 3 have the highest displacement at a lower slope angle, with location 1 and location 2 showing relatively better results than location 3. Structural and bioengineered preventive measures are needed in this area to reduce the vulnerability of possible slope failure.