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Owing to marked advances in instrumentation in X-ray and neutron scattering the time-dependent pair correlation function, the Van Hove function, can now be determined by inelastic X-ray and neutron scattering measurements. The local dynamics of water in real space and time is visualised by this approach. We discuss how the dynamic properties, such as viscosity and diffusion, can be elucidated through the Van Hove function of water. [ABSTRACT FROM AUTHOR]

Particle in cell simulation was applied to fit the measurements of protons and ions acceleration obtained using an fs laser pulse irradiating a thin foil in target-normal-sheath-acceleration regime. The simulation code calculates the maximum electrical field generated in the rear side of the target driving the forward ions acceleration. The electron density versus time and space, and the plasma temperatures are evaluated using a medium contrast laser at an intensity of about 1019 Wcm−2. Proton acceleration above 10 MeV was experimentally measured using SiC detectors connected in time-of-flight configuration. A comparison between theoretical aspects and experimental data is reported and discussed. [ABSTRACT FROM AUTHOR]

The contrast of space and place has long been an active topic of scholarly discussions in many disciplines. While spatial analysis enjoys a multitude of quantitative methods, the study of place remains mostly conceptual and descriptive. This paper expands upon the rich concepts of place in the literature to propose a quantitative framework for placial analysis based on events. Central to the proposed framework are three assumptions: (1) human experiences transform space to place; (2) events build human experiences in space; and (3) places emerge organically and may change characters, spatial extent and location over time through the shifts in occurrences and types of events in space and time. The proposed framework consists of three elements: clustering events, decomposing event distributions, and identifying the similarity of event clusters. We applied the framework to identify criminological places in the City of Dallas in the United States and the changes of these places from 1 June 2014 to 30 May 2018. [ABSTRACT FROM AUTHOR]

The Klein–Gordon equation plays an important role in mathematical physics. In this paper, a direct method which is very effective, simple, and convenient, is presented for solving the conformable fractional Klein–Gordon equation. Using this analytic method, the exact solutions of this equation are found in terms of the Jacobi elliptic functions. This method is applied to both time and space fractional equations. Some solutions are also illustrated by the graphics. [ABSTRACT FROM AUTHOR]

In this paper, we present the exact solutions obtained for the space–time conformable generalized Hirota–Satsuma-coupled KdV equation and coupled mKdV equation using the Atangana's conformable derivative. The conformable sub-equation method is applied to obtain the solutions; the solutions obtained are compared with the extended tanh-function method for the special case when the fractional order takes the integer order. The analytical solutions show that the conformable sub-equation method is very effective for the conformable-coupled KdV and mKdV equations. [ABSTRACT FROM AUTHOR]

Many metropolitan conceptualizations apply 'territorial grammar' when articulating the region. This paper approaches the metropolitan region as an entity whose extent and internal structure are negotiated in both space and time. We argue that the 'planning imagination', which is predominantly spatial in nature, must be temporalized by considering 'temporal grammar'. The main objective of this study is to explore how a temporal dimension can be integrated more effectively into how the metropolitan region is imagined and conceptualized. Therefore, we employ the dialogical concept of heteroglossia to present the metropolitan region as a continuous dialogue between municipalities of different power, as an open, ongoing and negotiated spatiotemporal unit. Our secondary aim is to employ this conceptualization in an empirical description of the spatiotemporal arrangement of a particular region (Brno, Czech Republic, summer 2015). For this purpose, we use data related to the opening hours of shops selling fast-moving consumer goods. Analysis revealed four specific voices present in the complex heteroglossia of the region: the voice of the core, the city of Brno; the voice of secondary urban centres; the voice of municipalities located in the hinterlands of secondary urban centres; and the voice of traditional agricultural municipalities. [ABSTRACT FROM AUTHOR]

This essay explores the relationship of two homeless youth—one queer and one trans—as they move together through and pass time in public space between the opening hours of their shelters and groups homes. Pulling from a critical ethnography of the experiences of trans and queer youth in New York City, this essay examines how these two youth come to know how to navigate and be in relation with the affects, structures, bodies, and discourses that comprise the city. The essay centers their relationship as an act of resistance, or queerruption as per this symposium, against normative assumptions about race, gender, and sexuality that dictate how the city is "supposed" to be used. The essay is written in a narrative form that asks readers to consider how they are coming to know these two youth through the ways they are animated in the text, with the purpose being to unpack the assumptions of presupposing who, what, and where trans and queer youth are thought to be. [ABSTRACT FROM AUTHOR]

The empirical quantiles of independent data provide a good summary of the underlying distribution of the observations. For high-dimensional time series defined in two dimensions, such as in space and time, one can define empirical quantiles of all observations at a given time point, but such time-wise quantiles can only reflect properties of the data at that time point. They often fail to capture the dynamic dependence of the data. In this article, we propose a new definition of empirical dynamic quantiles (EDQ) for high-dimensional time series that mitigates this limitation by imposing that the quantile must be one of the observed time series. The word dynamic emphasizes the fact that these newly defined quantiles capture the time evolution of the data. We prove that the EDQ converge to the time-wise quantiles under some weak conditions as the dimension increases. A fast algorithm to compute the dynamic quantiles is presented and the resulting quantiles are used to produce summary plots for a collection of many time series. We illustrate with two real datasets that the time-wise and dynamic quantiles convey different and complementary information. We also briefly compare the visualization provided by EDQ with that obtained by functional depth. The R code and a vignette for computing and plotting EDQ are available at. [ABSTRACT FROM AUTHOR]

This editorial introduces Archaeo-Ornithology as a distinct field of inquiry and discusses its multidisciplinary background and potential contribution to a more nuanced characterisation of changing human-animal interfaces through time and space. We propose a new conceptual model – grounded in the analysis of 'triangles of interaction' – to elucidate the interactional dynamics which underpin varying human-animal relationships. The utility of this approach is demonstrated by exploring the example of anthropogenic space as a key context of human-bird figurations. Each contributing paper of the special issue, which will be introduced in more detail below, foregrounds different aspects and emphasises varying dimensions of the triangle, thus contributing in different ways to archaeo-ornithological research. As highlighted throughout the introduction, however, archaeo-ornithological approaches are not only capable of shedding new light on old questions about the past, they also have the potential of addressing some pressing contemporary quandaries, including continuing debates on the Anthropocene. [ABSTRACT FROM AUTHOR]

However, for Eze, this response is a reference to moral imagination that fails to reorder itself and society in relation to its environment, but merely reflects that environment. As much as our experience has been disrupted by the misadventures of the colonial project, we have also contributed to our present state, and our attempts at blaming the West for all our failures is, as Eze calls it, a propaganda against ourselves (see Eze [1]: 340-341). Eze's preferred method of ordinary reason is one that is philosophic by virtue of shunning 'unphilosophical encroachments by culturally contextualist social morality and politics' (Eze [3]: 76). [Extracted from the article]

Due to the non-locality of fractional derivative, the analytical solution and good approximate solution of fractional partial differential equations are usually difficult to get. Reproducing kernel space is a perfect space in studying this type of equations, however the numerical results of equations by using the traditional reproducing kernel method (RKM) isn't very good. Based on this problem, we present the piecewise technique in the reproducing kernel space to solve this type of equations. The focus of this paper is to verify the stability and high accuracy of the present method by comparing the absolute error with traditional RKM and study the effect on absolute error for different values of α. Furthermore, we can study the distribution of entire space at a particular time period. Three numerical experiments are provided to verify the efficiency and stability of the proposed method. Meanwhile, it is tested by experiments that the change of the value of α has little effect on its accuracy. [ABSTRACT FROM AUTHOR]

Ontology has many applications to engineering but is not easily taken up by engineers. For example, specifying products in space and time together (four dimensions) enables more reliable modelling and analysis, but this work is primarily ontological and not accessible to most engineers. This paper summarises an existing method for integrating ontology and engineering, then applies it to four-dimensional requirements modelling, extending prior results. Requirements in this paper are treated as desired effects of a system on its operating environment. These effects are often respecified in multiple designs and tools, leading to redundancy and potential inconsistency. This can be addressed with centralised models of operating environment developed in systems engineering languages. These languages can specify the structure of operating environments formally enough to specify desired effects (except for spatial aspects), but cannot do the same for desired behaviour of those environments, because behaviours typically specify actions taken by a system to achieve those effects. This paper proposes new engineering-accessible extensions to logical system modelling for specifying intended environmental effects, including spatial relationships, without committing to the actions taken to achieve them. The proposed model supports centralised specifications of required system effects on their operating environments, enabling efficient integration with design. [ABSTRACT FROM AUTHOR]

In this paper, by applying order reduction approach, a second-order accurate box scheme is established to solve a nonlinear delayed convection-diffusion equations with Neumann boundary conditions. By the discrete energy method, it is shown that the difference scheme is uniquely solvable, and has a convergence rate of with respect to - norm in constrained and non-constrained temporal grids. Besides, for constrained temporal step, a Richardson extrapolation method (REM) used along with the box scheme, which makes final solution third-order accurate in both time and space, is developed in detail. Finally, numerical results confirm the accuracy and efficiency of our solvers. [ABSTRACT FROM AUTHOR]

In this article, the in-plane forced vibration behavior of transversely isotropic and laminated composite parabolic arches is examined by the unified scheme of the complementary functions method (CFM) and the Laplace transform theoretically. The anisotropy of the material of the arch, and the effects of the axial deformation, rotary inertia, and shear deformation are taken into account in the related assumptions and formulations. The arch is assumed to be made of anisotropic, linear elastic, and homogeneous material. For the solution of the governing equations, the RK5 (5th-order Runge-Kutta) algorithm has been used and for this aim, a software is written in FORTRAN. To transfer the obtained results back to the time space, an appropriate inverse method is used. Numerical results are presented and compared with solutions of ANSYS. As a result, the presented method is proved to be accurate and more efficient than the time integration methods. [ABSTRACT FROM AUTHOR]

In this paper, we analyzed changing of dynamics of redistribution of dopant during the manufacturing of diffusion-junction rectifier in a heterostructure due to radiation processing. In this regard, concentration of charge carriers will also be changed. We also introduce an analytical approach to analyze mass transport with account nonlinearity, space and time variation of parameters of the transport. [ABSTRACT FROM AUTHOR]

Cell migration is central to many developmental, physiologic and pathological processes, including cancer progression. The Ral GTPases (RalA and RalB) which act down-stream the Ras oncogenes, are key players in the coordination between membrane trafficking and actin polymerization. A major direct effector of Ral, the exocyst complex, works in polarized exocytosis and is at the center of multiple protein-protein interactions that support cell migration by promoting protrusion formation, front-rear polarization, and extra-cellular matrix degradation. In this review we describe the recent advancements in deciphering the molecular mechanisms underlying this role of Ral via exocyst on cell migration. Among others, we will discuss the recently identified cross-talk between Ral and Rac1 pathways: exocyst binds to a negative regulator (the RacGAP SH3BP1) and to the major effector (the Wave Regulatory Complex, WRC) of Rac1, the master regulator of protrusions. Next challenge will be to better characterize the dynamics in space and in time of these molecular interplays, to better understand the pleiotropic functions of Ral in both normal and cancer cells. [ABSTRACT FROM AUTHOR]

Wrong-way crashes on limited access highways continue to be a serious problem for state highway agencies and communities. These crashes are more likely to result in fatalities or serious injuries than other traffic incidents, due to vehicles travelling at high speeds, often involved on a roadway with limited vertical space and time to avoid a crash. This research study focused on wrong-way crashes that occurred on highways in the State of Kansas. Although these crashes represent a very small portion of crashes, wrong-way crashes were found to have a higher rate of fatalities and injuries as compared to other crash types. Using ten years of crash data, it was found that a typical wrong-way crash occurred under no adverse weather conditions, at a non-intersection location, in daylight or with streetlights present, involved alcohol or drugs, and resulted in a fatality or serious injury. An ordinary logistic model was developed to identify significant characteristics of wrong-way crashes. The model indicated that drivers under the influence of alcohol or drugs was found to be a significant in both fatal and injury wrong-way crashes. It was also found that certain lighting conditions were also significant, along with use of safety equipment and drivers over the age of 55 years old. Additional research is needed to further investigate wrong-way crashes and their causalities in Kansas on other roadway facilities including rural at-grade divided intersections. [ABSTRACT FROM AUTHOR]

Congestion is a dynamic phenomenon with elements of space and time, making it a promising application of probe vehicles. The purpose of this paper is to measure and visualize the magnitude and variability of congestion on the network scale using smartphone GPS travel data. The sample of data collected in Quebec City contained over 4000 drivers and 21,000 trips. The congestion index (CI) was calculated at the link level for each hour of the peak period and congestion was visualized at aggregate and disaggregate levels. Results showed that each peak period can be viewed as having an onset period and dissipation period lasting one hour. Congestion in the evening is greater and more dispersed than in the morning. Motorways, arterials, and collectors contribute most to peak period congestion, while residential links contribute little. Further analysis of the CI data is required for practical implementation in network planning or congestion remediation. [ABSTRACT FROM AUTHOR]

For many years trajectory similarity research has focused on raw trajectories, considering only space and time information. With the trajectory semantic enrichment, emerged the need for similarity measures that support space, time, and semantics. Although some trajectory similarity measures deal with all these dimensions, they consider only stops, ignoring the moves. We claim that, for some applications, the movement between stops is as important as the stops, and they must be considered in the similarity analysis. In this article, we propose SMSM, a novel similarity measure for semantic trajectories that considers both stops and moves. We evaluate SMSM with three trajectory datasets: (i) a synthetic trajectory dataset generated with the Hermoupolis semantic trajectory generator, (ii) a real trajectory dataset from the CRAWDAD project, and (iii) the Geolife dataset. The results show that SMSM overcomes state-of-the-art measures developed either for raw or semantic trajectories. [ABSTRACT FROM AUTHOR]

Massive spatio-temporal big data about human mobility have become increasingly available. Revealing underlying dynamic patterns from these data is essential for understanding people's behavior and urban deployment. Spatio-temporal autocorrelation analysis is an exploratory approach to recognizing data distribution in space and time. The most widely used spatial autocorrelation measurements, such as Moran's I and local indicators of spatial association (LISA), only apply to static data, so are powerless to spatio-temporal big data about human mobility. Thus, we proposed a new method by extending Moran's I to measure the spatial autocorrelation of time series data. Then the method was applied to taxi ride data in Beijing, China to reveal the spatial pattern of collective human mobility. The result shows that there is strong positive spatio-temporal autocorrelation within the 5th Ring Road, weak negative spatio-temporal autocorrelation nearby the Sixth Ring Road, and almost no spatio-temporal autocorrelation between the roads. Local spatial patterns of taxi travel were also recognized. This method is useful for discovering underlying patterns from spatio-temporal big data to understand human mobility. [ABSTRACT FROM AUTHOR]

Melting and solidification problems in presence of natural convection are known to require high computational resources. Very fine meshes are essential to accurately determine the flow structure and interface position between the different phases. In this work, a time-dependent adaptive remeshing method based on an efficient error estimator is presented. The proposed method greatly reduces the number of mesh elements while maintaining and even enhancing the efficiency of the simulations. A variant of the enthalpy-porosity formulation is used where the different thermo-physical properties between the solid–liquid phases are easily taken into account. A second order mixed finite element formulation for both space and time is employed for solving the momentum and energy equations. The efficiency of the proposed methodology is established by comparing solutions on very fine meshes with those obtained on adapted meshes and with existing experimental and numerical results found in the literature. [ABSTRACT FROM AUTHOR]

In this paper, we present a fourth-order in space and time block-structured adaptive mesh refinement algorithm for the compressible multicomponent reacting Navier–Stokes equations. The algorithm uses a finite-volume approach that incorporates a fourth-order discretisation of the convective terms. The time-stepping algorithm is based on a multi-level spectral deferred corrections method that enables explicit treatment of advection and diffusion coupled with an implicit treatment of reactions. The temporal scheme is embedded in a block-structured adaptive mesh refinement algorithm that includes subcycling in time with spectral deferred correction sweeps applied on levels. Here we present the details of the multi-level scheme paying particular attention to the treatment of coarse–fine boundaries required to maintain fourth-order accuracy in time. We then demonstrate the convergence properties of the algorithm on several test cases including both non-reacting and reacting flows. Finally we present simulations of a vitiated dimethyl ether jet in 2D and a turbulent hydrogen jet in 3D, both with detailed kinetics and transport. [ABSTRACT FROM AUTHOR]

This article looks at everyday encounters in Mostar to investigate how boundaries are enacted and displaced by its dwellers. Drawing on participant observation in two cafes, it considers boundaries not only in their spatial capacity, but in a confluence of space and time. It reflects on how owners and customers mobilize the idea of the pre-war city as a space of interethnic tolerance to criticize the contemporary city. It discusses how the creation of temporal boundaries complicate the narrative of the divided city and sheds light on attempts to restore places of co-existence in sharp contrast to the prevalent social order. [ABSTRACT FROM AUTHOR]

In this study, a more general version of F-expansion method is proposed. With this offered method, more than one Jacobi elliptic functions are located in the solution function. We seek analytical solutions of the space-time fractional cubic Schrodinger equation by use of the new type of F-expansion method. Consequently, multifarious exact analytical solutions consisting of single, double, and multiple combined Jacobi elliptic functions solutions are acquired. [ABSTRACT FROM AUTHOR]

The article first of all holds that environmental regulation has failed. This is because it is too weak to prevent the overstepping of ecological boundaries by humanity. In this legal regulation is reflected that human behavior is psychopathological. This collective mental illness may originate from false self-identification. Therefore, the author reviews the outcomes of modern natural sciences, such as quantum physics, cosmology, and nonlocal consciousness research. These results give sufficient support to argue, despite the traditional paradigm of materialism, that some aspects of consciousness are not limited by the space–time continuum. Moreover, all consciousness, regardless of its physical manifestations, is part of the universal Consciousness. From these scientific results, in line with ancient scriptures, an Eternal Order has evolved, which can be described at least by four fundamental and universal truths. This Eternal Order should be taken into account by positive law if humanity wants to reach fulfillment within the ecological limits of the Earth. [ABSTRACT FROM AUTHOR]

Several studies have demonstrated that LncRNAs can play major roles in cancer development. The creation of a catalog of LncRNAs expressed in T cell acute lymphoblastic leukemia (T-ALL) is thus of particular importance. However, this task is challenging as LncRNA expression is highly restricted in time and space manner and thus may greatly differ between samples. We performed a systematic transcript discovery in RNA-Seq data obtained from T-ALL primary cells and cell lines. This led to the identification of 2560 novel LncRNAs. After the integration of these transcripts into a large compendium of LncRNAs (n = 30478) containing both known LncRNAs and those previously described in T-ALLs, we then performed a systematic genomic and epigenetic characterization of these transcript models demonstrating that these novel LncRNAs share properties with known LncRNAs. Finally, we provide evidence that these novel transcripts could be enriched in LncRNAs with potential oncogenic effects and identified a subset of LncRNAs coregulated with T-ALL oncogenes. Overall, our study represents a comprehensive resource of LncRNAs expressed in T-ALL and might provide new cues on the role of lncRNAs in this type of leukemia. [ABSTRACT FROM AUTHOR]

Spreading of viral infection in the tissues such as lymph nodes or spleen depends on virus multiplication in the host cells, their transport and on the immune response. Reaction–diffusion systems of equations with delays in proliferation and death terms of the immune cells represent an appropriate model to study this process. The properties of the immune response and the initial viral load determine the regimes of infection spreading. In the proposed model, the proliferation rate of the immune cells is represented by a bell-shaped function of the virus concentration which increases for small concentrations and decreases if the concentration is sufficiently high. Here we use such a model system to show that an infection can be completely eliminated or it can remain present together with a decreased concentration of immune cells. Finally, immune cells can be completely exhausted leading to a high virus concentration in the tissue. In addition, we predicted two novel regimes of infection dynamics not observed before. Infection propagation in the tissue can occur as a superposition of two travelling waves: first wave propagates as a low level infection front followed by a high level infection front with a smaller speed of propagation. Both of the travelling waves can have a positive or a negative speed corresponding to infection advancement or retreat. These regimes can be accompanied by instabilities and the emergence of complex spatiotemporal patterns. Schematic representation of the processes underlying the population dynamics of virus infection spread and the antiviral immune response. [ABSTRACT FROM AUTHOR]

This article applies Mikhael Bakthin's concept of 'chronotope', understood as the ways in which writers narrate time and space and thus create worlds which enable subjectivities to emerge, to Tony Bennett's 'exhibitionary complex'. More precisely, I self-critically discuss two projects questioning the ocularcentric and objectifying chronotopes of museums: a film project on a colonial collection from the Niger Delta, today's Nigeria, at the National Maritime Museum in London and the curatorial project 'The Blind Spot' at the Kunsthalle Bremen in Germany. Both projects depended on the collaboration with anti-racist and diasporic partners who introduced performative ways of narrating colonial pasts, contradicting victimising accounts of colonisation and challenging white visitors to engage with embodied experiences of Empire. Moreover, my collaboration partners insisted on defining themselves and their histories beyond experiences of Empire and on envisioning decolonial futures. Can these chronotopes be brought into dialogue with the museums' attempts to come to terms with their colonial pasts? [ABSTRACT FROM AUTHOR]

While social programs are often assessed using short-term impact studies, longitudinal designs allow evaluators to capture change over time, identify longer-term outcomes, adapt instruments, and better understand participants in transition. A mixed methods design can be critical in understanding these dynamics; yet there is a lack of literature exploring the practical considerations of planning and conducting qualitative and quantitative data collection and analysis within longitudinal studies. This paper examines two different mixed methods frameworks used in a 5-year evaluation of three youth entrepreneurship programs in East Africa. We show how the evaluation team dealt with unique challenges across methods and over time, and how the design ultimately facilitated a richer understanding of program impacts and processes. Considerations for conducting this type of study are explored, related to the impact of longevity on analysis and research staff. Successfully using a longitudinal mixed methods approach requires researchers to be strategic and reflexive, and work in close collaboration. [ABSTRACT FROM AUTHOR]

This article introduces the methodological tool of diffraction (Barad, 2007) to re-imagine the performance-based work of two artists, Kyoko Hayashi and Ana Mendieta. Both artists' work are investigated in terms of wreckage. There is the individual wreckage of the body; Kyoko is a hibakusha - she has survived the devastation wrought by the atomic bomb dropped on Nagasaki in 1945. Mendieta met her death as she fell from a window, her husband inside the room of the window she fell out of. Both women explored colonial wreckages, performing their bodies as sites of such wreckages in unique installations and performative journeys. The two artists are diffracted through one another in this article. Having no relationship in time or space, their works are used here as prisms through which to investigate the phenomena of wreckage at the individual level: the performative body, and the phenomena of large-scale wreckages wrought by the Anthropocene. The Anthropocene refers to our geological era - an era in which the performativities of Mankind have actually penetrated the Earth's crust, changing its chemistry forever (Crutzen, 2002). Engaging in a diffractive reading of Hayashi and Mendieta, allows for new light to emerge around their stories and works, light that is concerned with matters of decoloniality, the body and time as performative entanglements of justice-to-come (Barad, 2007). [ABSTRACT FROM AUTHOR]

This paper presents a multinomial method for option pricing when the underlying asset follows an exponential Variance Gamma (VG) process. The continuous time VG process is approximated by a continuous time process with the same first four cumulants and then discretized in time and space. This approach is particularly convenient for pricing American and Bermudan options, which can be exercised before the expiration date. Numerical computations of European and American options are presented and compared with results obtained with finite differences method and with the Black-Scholes prices. [ABSTRACT FROM AUTHOR]

In this paper, I explore my life-long interest in amateur herpetology using an autoethnographic methodology and, in doing so, reveal the varied intersections of animals, leisure, place and identity within my own life experience. Informed by serious leisure theory and Stebbins' concept of the 'leisure career', I reflect on aspects of my life-history from childhood and adolescence through to the present day as a 56-year-old Anglo-Australian male, teasing out the diversity of ways that the leisure practices relating to my interest in this specific group of animals have been enabled and supported, spatially, structurally and socially. This analysis examines the intellectual, emotional and embodied ways that I have encountered and experienced reptiles across time and space, facilitated in the first instance by a supportive family which, in various ways, encouraged my entry into amateur herpetology. [ABSTRACT FROM AUTHOR]

While modernist or 'top-down', 'command-and-control' approaches to climate and migration worked at the surface or ontic level of the redistribution of entities in time and space, resilience approaches call for a different approach to mobility. These discourses construct mobilities that are more transformative; in fact, ones that question traditional liberal modernist notions of time and space and of entities with fixed essences. These mobilities do not concern moving entities in space but rethinking mobility in relation to space. Mobility then becomes more a matter of changing the understandings and practices relating to spaces and entities than of moving things from one place to another. Becoming 'mobile' thus would apply to the development of capabilities or 'response-abilities' to sense, adapt, recompose, repurpose and reimagine problems and possibilities; taking responses to crises beyond the static and binary conceptions of mobility and space. [ABSTRACT FROM AUTHOR]

Regularization has become a primary tool for developing reliable estimators of the covariance matrix in high-dimensional settings. To curb the curse of dimensionality, numerous methods assume that the population covariance (or inverse covariance) matrix is sparse, while making no particular structural assumptions on the desired pattern of sparsity. A highly-related, yet complementary, literature studies the specific setting in which the measured variables have a known ordering, in which case a banded population matrix is often assumed. While the banded approach is conceptually and computationally easier than asking for "patternless sparsity," it is only applicable in very specific situations (such as when data are measured over time or one-dimensional space). This work proposes a generalization of the notion of bandedness that greatly expands the range of problems in which banded estimators apply. We develop convex regularizers occupying the broad middle ground between the former approach of "patternless sparsity" and the latter reliance on having a known ordering. Our framework defines bandedness with respect to a known graph on the measured variables. Such a graph is available in diverse situations, and we provide a theoretical, computational, and applied treatment of two new estimators. An R package, called ggb, implements these new methods. Supplementary materials for this article are available online. [ABSTRACT FROM AUTHOR]

To date, critical examinations of smart cities have largely ignored their temporality. In this article, I consider smart cities from a spatiotemporal perspective, arguing that they produce a new timescape and constitute space–time machines. The first half of the article examines spatiotemporal relations and rhythms, exploring how smart cities are the products of and contribute to space–time compression, create new urban polyrhythms, alter the practices of scheduling, and change the pace and tempos of everyday activities. The second half of the article details how smart cities shape the nature of temporal modalities, considering how they reframe and utilize the relationship among the past, present, and future. The analysis draws from a set of forty-three interviews conducted in Dublin, Ireland, and highlights that much of the power of smart urbanism is derived from how it produces a new timescape, rather than simply reconfiguring spatial relations. [ABSTRACT FROM AUTHOR]

Well-established techniques exist for measuring the similarity of space–time paths. These measures support clustering and aggregation of space–time paths as well as moving objects database queries based on similar movement patterns or semantics. Little attention has been paid, however, to the analogous problem of measuring space–time prism (STP) similarity, despite comparable applications. This article presents and evaluates a method for measuring STP similarity through dimensionality reduction that leverages their inherent temporal ordering. The technique sweeps an STP along the time axis and derives one-dimensional temporal signatures based on a measured STP property that captures its geometry or semantics. These temporal signatures can be visualized directly as curves. We can also apply existing space–time path similarity measures to these signatures. To demonstrate the feasibility of this approach, we perform two sets of experiments measuring geometric and semantic similarity among STPs and assess the information within these curves using visualization, Fréchet distances, and clustering techniques. Results suggest that the temporal signature curves capture meaningful similarities and differences among STPs. [ABSTRACT FROM AUTHOR]

Eddy Current Testing (ECT) plays a key role in detecting cracks and defects in conductors. The present study examines for the first time how the subregion method as an effective mathematical and computational technique can be admixed with Finite Element Method (FEM) to study multiple defects parameters for ECT issues. Separating a defect region from the entire domain in any computational technique will save both time and storage space. Examples of different types of defects are presented in this article. A tangible result of processing time reduction by 90% has been achieved which has led us to consider the subregion FEM method as an effective method in solving different Nondestructive Evaluation (NDE) problems. An agreement between our results and others using classical FEM has been achieved which could lead to using this technique in online and field testing problems. The presented subregion FEM algorithm was verified experimentally with good agreement by testing Aluminum (T6061-T6) samples with defects. A Tunneling Magnetoresistive (TMR) sensor was used to measure the component of the magnetic field from normal to the sample top surface. A major component of minimizing processing time was achieved, which could lead to using this technique in online and field testing problems. [ABSTRACT FROM AUTHOR]

We characterize the agreement and disagreement of four publically available burned products (Fire CCI, Copernicus Burnt Area, MODIS MCD45A1, and MODIS MCD64A1) at a finer spatial and temporal scale than previous assessments using a grid of three-dimensional cells defined both in space and in time. Our analysis, conducted using seven years of data (2005-2011), shows that estimates of burned area vary greatly between products in terms of total area burned, the location of burning, and the timing of the burning. We use regional and monthly units for analysis to provide insight into the variation between products that can be lost when considering products yearly and/or globally. Comparison with independent, contemporaneous MODIS active fire observations provides one indication of which products most reasonably capture the burning regime. Our results have implications for the use of global burned area products in fire ecology, management and emissions applications. [ABSTRACT FROM AUTHOR]

Methodological advancements in geoarchaeology and spatial and chronological modeling are opening new avenues to interpreting large coastal shell-bearing sites. We document the developmental histories of two such sites around Prince Rupert Harbour, Canada, using systematic percussion coring, intensive radiocarbon dating, and 3D surface mapping with Total Station and LiDAR. We also re-analyze a third site (Boardwalk/GbTo-31) excavated and radiocarbon dated in the 1960s, 1970s, and early 2000s using archival field notes, site maps, and stratigraphic profiles georectified using LiDAR. We map the natural landform beneath the sites and document the degree to which people physically modified landforms through the deposition of massive shell accumulations. We model site development through time and space and use accumulation rates and OxCal modeling to test for intentional deposition events. All three sites demonstrate complex and heterogeneous occupation histories. At each we identify instances of very rapid deposition that effectively terraced and extended parts of the natural landform to create places for constructing houses, though these episodes take place within longer histories of slower quotidian deposition. The anthropogenic modifications to the coastline in this area are the result of these mixed processes associated with long histories of occupation. [ABSTRACT FROM AUTHOR]

Though we live in a 4-dimensional universe, our minds and bodies are not particularly good at perceiving and depicting 4 dimensions. This study contributes to our understanding of collaboration with abstract concepts by examining particular activities where bodily and experiential understandings may conflict with the conceptual domain. Specifically, upper secondary physics classrooms studying Einstein's general theory of relativity are taken as a setting to identify the representational practices and conceptual challenges that arise when learners attempt to make meaning with, and express conflicting notions of, space and time. To unpack these challenges, we draw on the concept of imagination and on theoretical perspectives that treat imagining as a social activity. We also present the concept of metaimagining to characterize layered processes in which learners attend to and manage shifts between their own imaginative activities. This concept is illustrated through a detailed analysis of an extended conversation between 2 upper secondary physics students working with general relativity and spacetime. The students perform a diverse set of imaginative activities that are strongly tied to communicative, cognitive, and bodily action. We also show how the unique domain of general relativity presents particular challenges to student meaning making of abstract concepts which in turn prompt metaimagining. Based on our analysis, we offer recommendations to improve instructional practices in general relativity and argue for the consideration of imagining as a transdisciplinary competency in math and science education. [ABSTRACT FROM AUTHOR]

Children growing up today face a multitude of climate-related challenges, requiring a capacity for creative and ethical modes of attending to both the known and unknown effects of a changing climate. In response to these challenges, I explore the potential in children's weathering encounters, as observed during an ethnographic research project titled Walking with Wildlife in Wild Weather Times. In particular, I consider the various ways children engage with the weather and what this reveals about our (human) interconnections and minglings with the weather world. In this paper, I focus specifically on the temporal dimensions of child/weather encounters. My aim is to show that taking the time with children to slow down and attend to the elemental affects in the world, can reveal a weathered entanglement of past, present and future and a foundation for a curious and open attentiveness in responding to the climate challenges ahead. [ABSTRACT FROM AUTHOR]

There is a growing cultural and social movement among youth who draw on spoken word poetry and documentary style videos to participate in the new media landscape. Many multimedia poems have appeared on social media sites such as YouTube and Vimeo as a form of participatory politics. In this article, the author takes up a discussion of translocal practices and 'translocal assemblage' wherein individuals and groups engage in the exchange of ideas across space and time. One example is a multimedia poem about the underrepresentation and invisibility of racialized minority students at a major American university. This viral multimedia poem remixed elsewhere based on students' experiences at another university demonstrates not only the potential of translocal assemblage in participatory politics but also the practice of alternative media in the movement toward racial justice. That is, young people are finding civic resources and building on each other's work to challenge the social order. Pedagogically, the author built on the theoretical underpinning of translocal assemblage to shape work with students in the college classroom who, in turn, produced other genres of alternative media. The resultant video documentaries about locally unjust social arrangements make evident the subtle nature of cultural flows that have direct consequences for critical studies in education. [ABSTRACT FROM AUTHOR]

Urban system is shaped by the interactions between different regions and regions planned by the government, then reshaped by human activities and residents' needs. Understanding the changes of regional structure and dynamics of city function based on the residents' movement demand are important to evaluate and adjust the planning and management of urban services and internal structures. This paper constructed a probabilistic factor model on the basis of probabilistic latent semantic analysis and tensor decomposition, for purpose of understanding the higher order interactive population mobility and its impact on urban structure changes. First, a four-dimensional tensor of time (T) × week (W) × origin (O) × destination (D) was constructed to identify the day-to-day activities in three time modes and weekly regularity of weekday/weekend pattern. Then we reclassified the urban regions based on the space clustering formed by the space factor matrix and core tensor. Finally, we further analysed the space-time interaction on different time scales to deduce the actual function and connection strength of each region. Our research shows that the application of individual-based spatial-temporal data in human mobility and space-time interaction study can help to analyse urban spatial structure and understand the actual regional function from a new perspective. [ABSTRACT FROM AUTHOR]

The monumental paintings of the Postrimerías [Four Last Things] from the church of Carabuco (1684) serve as objects to study the complex dynamics of the visual and performative production of religious knowledge in a colonial contact zone. The article presents different 'readings' of the series that focus on possible uses and receptions of the paintings by local actors. These readings are based, on the one hand, on the idea of conceiving the series as a 'cycle of meditation' and product of the influences of Christian mysticism that played an important role in the 'eschatological politics of conversion' of the southern Andean Highlands. On the other hand, the paintings relate the eschatological message with the local hagiographic narratives of a pre-Hispanic apostle associated simultaneously with the Christian apostle Bartholomew and the Andean deity Tunupa—the most important figure of Aymara mythology. These works therefore represent objects of memory that participate in the local construction of time and space and that refer not only to Christian eschatological concepts but also to local Andean ontologies. [ABSTRACT FROM AUTHOR]

We present the time-spatial regularity of the nonlocal stochastic convolution for Caputo-type time fractional nonlocal Ornstein–Ulenbeck equations by the generalized Mittag–Leffler functions and Mainardi function, and establish the existence and uniqueness of mild solutions for time fractional and space nonlocal stochastic nonlinear Schrödinger equation driven by Gaussian white noise. In addition, the global mild solution is also shown. [ABSTRACT FROM AUTHOR]

Treating conditionals as probabilistic statements has been referred to as a defining feature of the "new paradigm" in cognitive psychology. Doing so is attractive for several reasons, but it complicates the problem of assessing the merits of conditional arguments. We consider several variables that relate to judging the persuasiveness of conditional arguments with uncertain (probabilistic) premises. We also explore ways of judging the consistency of people's beliefs as represented by components of conditional arguments. Experimental results provide evidence that inconsistencies in beliefs are more prevalent if the arguments' components are spatially and temporally dispersed than if they are contiguous in space and time. This supports the idea that assuring the consistency among even a small number of beliefs is difficult to do, especially if the beliefs in question are not brought into consciousness at the same time; but consistency can be enhanced when beliefs are considered simultaneously or nearly so. [ABSTRACT FROM AUTHOR]

In this article I explore silence as dialogue in human communication and address its relevance to silence in heritage sites and museums. Instead of treating silent responses as negative or pedagogical failure, I approach silence from an eclectic perspective informed by linguistic philosophy, social anthropology and cultural psychology and present an analysis of dialogic silence in relation to the nearly 500-year-old ritual practice of Chado, commonly known as the Japanese tea ceremony. I engage with key concepts of dialogue and silence in order to draw parallels between museums and heritage sites on one hand, and the practice of Chado, performed in the tearoom, on the other. I suggest how the performance of ritual in the Chado tearoom takes place in a heterotopic and heterochronic space of dialogue and of contemplation in silence, where people set aside the concerns of everyday life in a suspended time away from an otherwise unpredictable and violence-prone world. I then argue that heritage sites and museums can be seen as spaces of contemplation akin to the space of the tea ceremony, a comparison which offers an alternative perspective on the crisis of representation, the limitations of language and the problem of visitor fatigue. [ABSTRACT FROM AUTHOR]

We propose a novel approach to network-based event likelihood modeling that estimates the probabilities of event occurrences on a network and identifies the influences of site and situation characteristics. Our premise is that the occurrences of events that involve human activities are subject to site and situational characteristics, and an understanding of event occurrences serves the basis for preparation or mitigation. Using data from Dallas, Texas, USA, we take the proposed approach to estimate the likelihood of traffic accidents based on binary (event or nonevent) space-time atoms of 100-m road segments and 1-h intervals. We choose 12 variables representing time, site characteristics, and situational conditions based on literature reviews to develop logistic regression and random forest models. The traffic accident data on even days were used for model construction and data on odd days for model testing. Both models result in comparable accuracy at 84.11% (logistic regression) and 85.42% (random forest) with significant differences in the spatial patterns of how site and situation correlate to traffic accidents. The difference signals the dynamic influence of site and situation characteristics on the event likelihood over time. The proposed approach shall be applicable to other point events on a network. [ABSTRACT FROM AUTHOR]

How are the domains of space and time related? One approach, A Theory of Magnitude (ATOM), proposes an undifferentiated system of magnitude representation in the brain, predicting that space and time are symmetrically related, while Conceptual Metaphor Theory (CMT) proposes that we represent time using spatial metaphors, predicting asymmetrical interactions between domains. Tau and Kappa effects are perceptual phenomena that arise when observers judge the distance/duration between consecutive stimuli in sequence: Timing affects the perception of space (Tau) and spacing affects the perception of time (Kappa). Interference bidirectionality has been taken as evidence for ATOM. CMT proponents argue that interference may result from the perceiver imputing velocity to the stimuli. Here, the Tau and Kappa paradigm was modified to reduce the illusion of imputed velocity by manipulating stimuli parameters. In favor of CMT, we found that when the illusion of imputed velocity is reduced, asymmetrical interference arises: the Tau effect is eliminated while the Kappa effect remains intact. [ABSTRACT FROM AUTHOR]

Movement speed-accuracy trade-off is a function of the space-time constraints of the task. We investigated the space-time account of Hancock and Newell (1985) and the hypothesis of complementarity between the four moments of the error distribution in space and time. Twelve participants performed 15 conditions in a line drawing task composed of different spatial (10, 20, and 30 cm) and temporal (250 to 2,500 ms) criteria. The results showed that all moments of distributions changed systematically between conditions but there were some departures from the Hancock and Newell predictions. In contrast, individual analysis revealed the complementarity of the spatial and temporal error including a trade-off between the four moments of error. These findings support a complementary space-time account of movement speed and accuracy. [ABSTRACT FROM AUTHOR]