Relative Frame Of Reference Research Articles

Effects of animacy and linguistic construction on the interpretation of spatial descriptions in English and Spanish

abstractThe languages of the world differ in their use of intrinsic, relative, and absolute reference frames to describe spatial relationships, but factors guiding reference frame choices are not yet well understood. This paper addresses the role of animacy and linguistic construction in reference frame choices in English and Spanish. During each trial of two experiments, adult participants saw a spatial scene along with a sentence describing the location of an object (locatum) relative to another object (relatum) that was animate or human(-like) to varying degrees. The scene presented two possible referents for the locatum, and participants decided which referent the description referred to, revealing which reference frame they used to interpret the sentence. Results showed that reference frame choices differed systematically between languages. In English, the non-possessive construction (X is to the left of Y) was consistently associated with the relative reference frame, and the possessive construction (X is on Y’s left) was associated with the intrinsic reference frame. In Spanish, the intrinsic interpretation was dominant throughout, except for the non-possessive construction with relata that were not anthropomorphic, animate, or human. We discuss the results with respect to the languages’ syntactic repertory, and the notion of inalienable possession.

Role of polarizability of a CN fullerene cage in A@CN photoionization and e−–CN scattering: the size effect

We show that, in contradiction to intuitive perception, the impact of polarization of a CN cage by the outgoing photoelectron on photoionization of a A@CN endohedral atom decreases as the size of CN increases. This is counter-intuitive, owing to the fact that the polarizability of CN drastically increases with the increase of N. Furthermore, we demonstrate that this is also in contrast to the polarization impact on elastic electron scattering off empty fullerenes; for the latter, the bigger the CN cage (the greater its polarizability), the greater the polarization impact is on the scattering process. We provide researchers with a ‘relative frame of reference’ for understanding how the increase in the size of the cage affects the polarization impact on the corresponding photoionization and electron scattering processes. Our findings are supported by the direct calculations of the photoionization and electron scattering cross sections for selected fullerene cages from ‘dwarf’ C20 to ‘giant’ C240. The calculations are performed in the framework of a semi-empirical modeling of CN and A@CN fullerene systems obtained with and without account for the dipole static polarizability of a fullerene cage.

Flexibility in adopting relative frames of reference in dorsal and lateral settings.

The relative frame of reference (FoR) is used to describe spatial relations between two objects from an observer's perspective. Standard, frontal referencing situations with objects located in the observer's visual field afford three well-established variants: translation, reflection, and rotation. Here, we focus on references in non-standard situations with objects located at the back or at the side of an observer (dorsal and lateral, respectively). We scrutinise the consistency assumption, which was introduced to infer the covert strategy used in dorsal tasks from an ambiguous overt response: that, when confronted with a non-standard situation, people adopt a strategy consistent with how they construct the relative FoR in frontal situations. Lateral tasks enable us to disentangle the ambiguous response. The results of a study in Norway and Germany support the consistency assumption in part: Nearly all participants with a preference for translation in frontal tasks applied translation in lateral tasks, and some participants with a preference for reflection in frontal tasks turned towards the objects before applying reflection in lateral tasks. Most other participants with a preference for reflection in frontal tasks, however, switched to translation in lateral tasks. The latter may be due to a specific affordance of the lateral arrangements, which invite translation as the easier strategy compared to the alternative derived from reflection. Our findings indicate that people do not apply their preferred variant of the relative FoR to all kinds of situations, but rather flexibly adapt their strategy when it is more convenient to do so.

Zamansal Dilde Dışsal Referans

Referans çerçeveleri, nesneler arasındaki uzamsal ilişkileri belli bir perspektiften belirlemeye, tanımlamaya ve hesaplamaya yarayan zihinsel ve/ya dilsel koordinat sistemleridir (Bender vd., 2010, s.286; Bender vd., 2012, s.1; Bennardo, 2004, s.1; Majid vd., 2004, s.108). Bunun için sağladıkları temel strateji, uzamda konumlanmak istenen bir nesneden belli bir uzaklıkta bulunan ve ortamda öne çıkan diğer bir nesne seçmek, daha sonra da bu referans nesne üzerinden bir açı tanımlayarak bir arama alanı oluşturmaktır. Böylelikle, bir nesnenin konumu, diğerininki üzerinden belirlenebilmiş olur (Levinson, 2003, s.67) Evrensel olarak üç referans çerçevesi bulunduğu kabul edilmektedir (Levinson, 1996, 2003; Levelt, 1996; Tversky, 1996): Göreli referans çerçevesi, konuşucunun bakış açısını ve yönelimini temel almaktadır ve başına-ayaklarına, vücudunun önüne arkasına, sağına-soluna göre üç farklı doğrultuda olabilmektedir. İçsel referans çerçevesi, belli bir nesnenin ön-tanımlı içsel özelliklerini temel almakta ve eksenler bunlar üzerinden tanımlanmaktadır. Dışsal referans çerçevesinde ise, içinde bulunulan ortama ait belirgin özellikler eksenin doğrultusunu belirlemekte kullanılmaktadır (Carlson-Radvansky ve Logan, 1997, s.412). Temelde uzam alanıyla ilişkili olan 'referans çerçevesi' kavramını zaman alanına da uyarlayan çalışmalara alanyazında gittikçe daha çok rastlanmaktadır. Ancak bu çalışmalarda verilen dilsel örnekler son derece kısıtlıdır. Bu yazıda, söz konusu kısıtlılığın 'dışsal referans' alt türü için ne türden sorunlar ortaya çıkardığı ele alınmakta ve alternatif bakış açıları tartışılmaktadır.

Crustal deformation characteristics of Sichuan-Yunnan region in China on the constraint of multi-periods of GPS velocity fields

In order to obtain deformation parameters in each block of Sichuan-Yunnan Region (SYG) in China by stages and establish a dynamic model about the variation of the strain rate fields and the surface expansion in this area, we taken the Global Positioning System (GPS) sites velocity in the region as constrained condition and taken advantage of the block strain calculation model based on spherical surface. We also analyzed the deformation of the active blocks in the whole SYG before and after the Wenchuan earthquake, and analyzed the deformation of active blocks near the epicenter of the Wenchuan earthquake in detail. The results show that, (1) Under the effects of the carving from India plate and the crimping from the potential energy of Tibetan Plateau for a long time, there is a certain periodicity in crustal deformation in SYG. And the period change and the earthquake occurrence have a good agreement. (2) The differences in GPS velocity fields relative Eurasian reference frame shows that the Wenchuan earthquake and the Ya'an earthquake mainly affect the crustal movement in the central and southern part of SYG, and the average velocity difference is about 4–8 mm/a for the Wenchuan earthquake and 2–4 mm/a for the Ya'an earthquake. (3) For the Wenchuan earthquake, the average strain changed from 10 to 20 nanostrian/a before earthquake to 40–50 nanostrian/a after the earthquake, but before and after the Ya’an earthquake, the strain value increased from about 15 nanostrian/a to about 30 nanostrian/a. (4) The Wenchuan earthquake has changed the strain parameter of each active block more or less. Especially, the Longmen block and Chengdu block near the epicenter. The research provides fundamental material for the study of the dynamic mechanism of the push extrusion from the north-east of the India plate and the crimp from Qinghai Tibet Plateau, and it also provides support for the study of crustal stress variation and earthquake prediction in Sichuan Yunnan region.

Influence of Rotor Tip Blockage on Near Stall Blade Vibrations in an Axial Compressor Rig

Rotor blade vibrations observed in the Darmstadt transonic compressor rig are investigated in this paper. The vibrations are nonsynchronous and occur in the near stall (NS) operating region. Rotor tip flow fluctuations traveling near the leading edge (LE) against the direction of rotation (in the rotor relative frame of reference) with about 50% blade tip speed are found to be the reason for the occurrence of the vibrations. The investigations show that the blockage at the rotor tip is an important factor for the aeroelastic stability of the compressor in the NS region. It is found that by application of a recirculating tip injection (TI) casing treatment, the aeroelastic stability increases as a result of reduced blockage in the rotor tip region.

A relative frame of reference underlies reversed depth perception in anticorrelated random-dot stereograms.

Binocular disparity is represented by interocular cross-correlation of visual images in the striate and some extrastriate cortices. This correlation-based representation produces reversed depth perception in a binocularly anticorrelated random-dot stereogram (aRDS) when it is accompanied by an adjacent correlated RDS (cRDS). Removal of the cRDS or spatial separation between the aRDS and cRDS abolishes reversed depth perception. However, how an immediate plane supports reversed depth perception is unclear. One possible explanation is that the correlation-based representation generates reversed depth based on the relative disparity between the aRDS and cRDS rather than the absolute disparity of the aRDS. Here, we psychophysically tested this hypothesis. We found that participants perceived reversed depth in an aRDS with zero absolute disparity when it was surrounded by a cRDS with nonzero absolute disparity (i.e., nonzero relative disparity), suggesting a role of relative disparity on the depth reversal. In addition, manipulation of the absolute disparities of the central aRDS and surrounding cRDS caused depth perception to reverse with respect to the depth of the surround. Further, depth reversal persisted after swapping the locations of the two RDSs. A model of relative-disparity encoding explains all these results. We conclude that reversed depth perception in aRDSs occurs in a relative frame of reference and suggest that the visual system contains correlation-based representation that encodes relative disparity.

How Grammar Encodes Space in Cogtse Rgyalrong

This paper presents the grammatical systems that are used for the concepts of space in the Cogtse dialect of Rgyalrong. Cogtse is noted for the way it lexicalizes a rich set of orientations (up-down, east-west, upstream-downstream) in terms of nominals, pronominals, verbs, and adverbials. Together with locative postpositions and the relator-noun construction, they constitute the three primary kinds of grammatical devices to incorporate notions of space. Despite the fact that Cogtse lexicalizes the intrinsic, relative, and absolute (based on the six orientations) frames of reference; no occurrence of ‘left’ and ‘right’ has been observed in the discourse data, spontaneous or preplanned. Speakers clearly prefer the absolute references that take the above-mentioned orientations as the basis. Finally, this paper illustrates from two socio-cultural perspectives how entrenched the orientation system is in Rgyalrong. The selection of semantically-dependent perfectivizer reveals the way Rgyalrong speakers conceptualize events in orientational terms; while the seating arrangement in the Rgyalrong house demonstrates that in assigning orientation terms to refer to various indoor spaces, cultural conceptions override natural geographical settings.

Effect of axial skewed slot casing treatment in a transonic fan

This paper reports on a time-accurate numerical investigation of axial-skewed slot casing treatment in a high-speed axial fan. Twenty-two axial and radial skewed slots are placed over the casing of the rotor and choke to stall unsteady computations are conducted. Results show that endwall fluid is absorbed by the slots from the downstream part of the blade passage and is injected to the upstream part with a swirl contrary to the blade rotation. This gives the injected fluid a great circumferential velocity component in the relative frame of reference. The shock is, hence, pushed toward the trailing-edge plane and the pressure difference between the pressure and suction surfaces is reduced. Consequently, the occurrence of the leading-edge vortex spillage, which is believed to be the key to stall initiation for the current rotor, is postponed to lower mass flow rates.

A rotating reference frame‐based lattice Boltzmann flux solver for simulation of turbomachinery flows

SummaryIn this paper, the newly developed lattice Boltzmann flux solver (LBFS) is developed into a version in the rotating frame of reference for simulation of turbomachinery flows. LBFS is a finite volume solver for the solution of macroscopic governing differential equations. Unlike conventional upwind or Godunov‐type flux solvers which are constructed by considering the mathematical properties of Euler equations, it evaluates numerical fluxes at the cell interface by reconstructing local solution of lattice Boltzmann equation (LBE). In other words, the numerical fluxes are physically determined rather than by some mathematical approximation. The LBE is herein expressed in a relative frame of reference in order to correctly recover the macroscopic equations, which is also the basis of LBFS. To solve the LBE, an appropriate lattice Boltzmann model needs to be established in advance. This includes both the determinations of the discrete velocity model and its associated equilibrium distribution functions. Particularly, a simple and effective D1Q4 model is adopted, and the equilibrium distribution functions could be efficiently obtained by using the direct method. The present LBFS is validated by several inviscid and viscous test cases. The numerical results demonstrate that it could be well applied to typical and complex turbomachinery flows with favorable accuracy. It is also shown that LBFS has a delicate dissipation mechanism and is thus free of some artificial fixes, which are often needed in conventional schemes. Copyright © 2016 John Wiley & Sons, Ltd.

Perspective taking in referring to objects behind versus in front of an observer: Frames of reference, intraindividual consistency, and response latencies.

Speakers of English and German typically adopt the reflection variant of the relative frame of reference (FoR) in order to describe how nonoriented objects that are located in front of them are related to one another. Little is known, however, about how they proceed in dorsal settings, with objects located in their back. In this article, we explore the turn hypothesis, which assumes a (mental) 180° turn of the observer to face the objects, converting the dorsal into a frontal situation, so that the preferred FoR variant for frontal settings can be applied. To elicit spatial references, we used photographs that showed an observer and two objects either in the observer's visual field (frontal condition) or in the observer's back (dorsal condition). The observer was looking either in the same direction as the referencing individual (aligned perspectives) or in the opposite direction (vis-à-vis perspective). Data from two experiments show that while participants do adopt the observer's perspective, their references in dorsal settings are incompatible with the turn hypothesis. Analyses of response latencies indicate additional cognitive costs for establishing a FoR for the very first item in the dorsal condition as compared to the frontal condition, but fast adaption for subsequent items, and high intraindividual consistency in FoR choice in both conditions. Maintaining the assumption that references in dorsal settings should be compatible with the variant of the relative FoR adopted in frontal settings, participants' references can be explained by assuming a backward projection that gets by without a (mental) turn of the observer.

Spatial Language and Culture: Cardinal Directions in Negev Arabic

Negev Arabic displays a unique spatial system characterized by referential complementarity: Intrinsic, Relative, and Absolute frames of reference serve all speakers and are selected according to properties of the Ground. The Absolute frame of reference, employing cardinal directions, represents the lateral axis of all Ground-objects and serves as a default frame for problematic cases, such as modern, culturally alien objects; this frame of reference largely replaces right and left and serves, e.g., as a means to locate Figures in non-prototypical axial positions or in relation to modern Ground-objects. As in other Arabic dialects, cardinal directions also encode cultural, metaphorical, and symbolic meanings—especially east and west; north and south have not developed cultural salience.

Representation and discovery of building patterns: a three-level relational approach

ABSTRACTBuilding patterns exhibited collectively by a group of buildings are fundamental to understanding urban forms, classifying urban scenes, analyzing urban landscapes, and generalizing maps. The existing studies have used geometric homogeneity or regularity to represent and discover limited patterns for map generalization, or used interval and rectangle algebra to represent relations between spatial objects. These approaches, however, cannot illustrate how patterns are produced by using syntax or grammar (i.e. relations between buildings) to link words (i.e. buildings) into sentences (i.e. building patterns), making it impossible to represent and discover building patterns with diverse structures. This study presents a relation-based approach to formalize and discover arbitrary building patterns at three abstract levels. At the bottom level, a relative and local frame of reference is defined, and 169 basic relations are derived to represent relative positions between buildings. At the middle level, the 169 relations, qualitative angle description, and qualitative size are combined to formalize important semantic relations between two buildings, which include collinear, perpendicular, and parallel relations. At the top level, the relations at the bottom and middle levels are used to formalize three types of building patterns, including collinear patterns, the structured patterns with acceptable names, and other patterns of interest. Algorithms implementing the three levels of relations are presented and applied to demonstrate the effectiveness of the proposed approach in discovering building patterns from databases and querying building patterns. The results indicate that the relational approach is generic to effectively represent and discover building patterns with arbitrary structures. In addition, it complements the existing geometric methods for recognizing building patterns, and the interval and rectangle algebra for representing building relations.

Electron elastic scattering offA@C60: The role of atomic polarization under confinement

The present paper explores possible features of electron elastic scattering off endohedral fullerenes $A$@C$_{60}$. It focuses on how dynamical polarization of the encapsulated atom $A$ by an incident electron might alter scattering off $A$@C$_{60}$ compared to the static-atom-$A$ case, as well as how the C$_{60}$ confinement modifies the impact of atomic polarization on electron scattering compared to the free-atom case. The aim is to provide researchers with a "relative frame of reference" for understanding which part of the scattering processes could be due to electron scattering off the encapsulated atom and which due to scattering off the C$_{60}$ cage. To meet the goal, the C$_{60}$ cage is modeled by an attractive spherical potential of a certain inner radius, thickness, and depth which is a model used frequently in a great variety of fullerene studies to date. Then, the Dyson equation for the self-energy part of the Green's function of an incident electron moving in the combined field of an encapsulated atom $A$ and C$_{60}$ is solved in order to account for the impact of dynamical polarization of the encaged atom upon $e + A@{\rm C_{60}}$ scattering. The Ba@C$_{60}$ endohedral is chosen as the case study. The impact is found to be significant, and its utterly different role compared to that in $e + Ba$ scattering is unraveled.

Turn around to have a look? Spatial referencing in dorsal vs. frontal settings in cross-linguistic comparison.

When referring to an object in relation to another, speakers of many languages can adopt a relative frame of reference (FoR). Following Levinson (2003), this kind of FoR can be established by projecting an observer's perspective onto the ground object either by translation, reflection, or rotation. So far, research on spatial FoRs has largely ignored the extent of variation in which of these projections are preferred generally, and specifically what kind of FoR is established for spatial arrays in one's back. This may seem justified by assumptions on “natural” preferences: for reflection in frontal settings (Canonical Encounter Hypothesis), and for converting dorsal into frontal situations by a turn of the observer before a reference is made (Turn Hypothesis). We scrutinize these assumptions by comparing the FoRs adopted for small-scale, static spatial arrays by speakers of four languages (German, US-English, Mandarin Chinese, and Tongan). Addressing the problem of inherent ambiguities on the item level when assessing FoRs from spatial prepositions, we use a multinomial processing tree (MPT) model for estimating probabilities of referencing strategies across sets of items. Substantial differences in frontal settings, both between and within languages, disprove the Canonical Encounter Hypothesis—translation occurs as frequently as reflection across samples. In dorsal settings, in contrast, the same type of response dominates in all samples. We suggest that this response is produced by a backward projection of the observer's coordinate system in correspondence with the two main FoR preferences for frontal settings. However, none of these strategies involves a turn of the observer, thus also disproving the Turn Hypothesis. In conclusion, we discuss possible causes of the observed variability, explore links between the domains of space and time, and reflect the relation between language, communication, and culture.

Formation and Dissipation of Karman Vortex Street in an Accelerating Flow Past a Circular Cylinder

Prediction of Karman vortex street in a flow past circular cylinder has become a benchmark problem and many new numerical methods are validated by reproducing the phenomena. The formation and dissipation of Karman vortex street occurs in a range of Reynolds number. But, the conventional Navier-Stokes equations derived in inertial frame of reference based on constant relative velocity are limited to fluid flow problem at a given freestream velocity or Reynolds number. Therefore, in order to capture the formation and dissipation of karman vortex street, several simulations are to be carried out at different freestream velocites. Even then, such simulations will not reveal the continous phenomena of formation and dissipation of vortices. In this work, Navier-Stokes equations are obtained from first principles for fluid flow problems with linear external acceleration in relative acceleration frame of reference, in a form most suited for numerical study. Using these equations, numerical simulation of accelerating flow over circular cylinder is carried out for Reynolds number range, 68 to 1360. The formation and dissipation of Karman vortex street is captured in a single simulation and the results are compared with conventional simulations at various Reynolds numbers. The issues in physical modeling and numerics of using constant freestream acceleration are also discussed in brief. From these simulations, it is demonstrated that the physical phenomena obtained by solving conventional Navier-Stokes equations at various freestream velocities can obtained in a single simulation by using the Navier-Stokes equations written in relative acceleration frame of reference. These equation can be used to explore the physics of accelerating flows in a continuous scenario, without undertaking numerous conventional simulations at various constant freestream velocities.

Experimental investigation of the vortex breakdown in a lean premixing prevaporizing burner

The spiral vortex breakdown has been experimentally studied in the flow field generated by a lean premixing prevaporizing (LPP) combustor model. The vortex breakdown structures are characterized by a solid-body rotation. Hence, phase-locked laser Doppler velocimeter measurements, performed in a meridional plane, have allowed reconstruction of the periodic velocity and Reynolds stress fields within a time period and in a relative cylindrical frame of reference. Then, the turbulent kinetic energy (TKE) production term has been computed. The velocity distribution analysis indicates that a spiral vortex core wraps around an inner reverse flow zone. Both are characterized by a precessing motion. Then, the main contributions to the TKE production have been identified together with their spatial locations. Their distribution indicates that the maxima are placed in two regions: one located between the inner reverse flow and the spiral vortex and the second between the spiral vortex core and the external nearly quiescent fluid. In the latter, the TKE production term distributions have the features of a Kelvin–Helmholtz-like instability. In the former, the TKE production seems to be related to a Kelvin–Helmholtz-like instability only at the interface between the bubble and the spiral vortex core.

The Contact Diffusion of Linguistic Practices

We examine the extent to which practices of language use may be diffused through language contact and areally shared, using data on spatial reference frame use by speakers of eight indigenous languages from in and around the Mesoamerican linguistic area and three varieties of Spanish. Regression models show that the frequency of L2-Spanish use by speakers of the indigenous languages predicts the use of relative reference frames in the L1 even when literacy and education levels are accounted for. A significant difference in frame use between the Mesoamerican and non-Mesoamerican indigenous languages further supports the contact diffusion analysis.

Equilibrium Positions for UAV Flight by Dynamic Soaring

Dynamic soaring is a special flying technique designed to allow UAVs (unmanned aerial vehicles) to extract energy from wind gradient field and enable UAVs to increase the endurance. In order to figure out the energy-extraction mechanisms in dynamic soaring, a noninertial wind relative reference frame of aircraft is built. In the noninertial frame, there is an inertial force which is created by gradient wind field. When the wind gradient(GW)and the components of airspeed(vzvx)are positive, inertial force(F)makes positive work to the aircraft. In the meantime, an equilibrium position theory of dynamic soaring is proposed. At the equilibrium positions, the increased potential energy is greater than the wasted kinetic energy when the aircraft is flying upwards. The mechanical energy is increased in this way, and the aircraft can store energy for flight. According to the extreme value theory, contour line figures of the maximum function and the component of airspeed(vz)are obtained to find out the aircraft’s lifting balance allowance in dynamic soaring. Moreover, this equilibrium position theory can also help to conduct an aircraft to acquire energy from the environment constantly.

Multi-platform Observations Characterizing the Afternoon-to-Evening Transition of the Planetary Boundary Layer in Northern Alabama, USA

Observations from the University of Alabama in Huntsville campus and ground-based scanning radar for over 140 total spring, summer, and autumn cases are studied to contribute to the relative scarcity of long-term datasets documenting the afternoon-to-evening transition of the planetary boundary layer. A sunset relative frame of reference is employed, focusing on the period 3 h before to 2 h after astronomical sunset, and several findings are consistent with previous investigations. Fluctuating components of wind and temperature computed from nearly collocated surface, Doppler wind profiler, and vertically pointing Doppler lidar measurements show a consistent decline as turbulence intensity diminishes through the transition. When normalized by their initial values, a pattern emerges: temperature variances decline slowly at first then quite abruptly after about 90 min before sunset. After the temperature variances begin to wane, vertical velocity fluctuations decrease, and the rate of their decay increases as vigorous thermal structures diminish. The fastest decline of the horizontal wind variance occurs after an accelerated vertical wind variance decrease, and the horizontal wind fluctuations display the slowest rate of decrease among these quantities. Near-surface humidity measurements show increases in mean water vapour mixing ratio as a steady rise generally beginning about 80 min prior to sunset. Composites of mean lidar vertical motion show final convective-type towers of upward motion occur about an hour before sunset and are coherent through 800 m (all heights a.g.l.). Lidar vertical motion variance at 195 m decreases by more than an order of magnitude approaching sunset, then remains below 0.01 m\(^{2}\) s\(^{-2}\) for the rest of the studied time frame. Subtle, but steady, increases in both horizontal wind speed and radar-derived horizontal wind convergence above the surface layer (at 300 m) span the entire 5-h time frame. While the convergence results show a broad range, an increase in the mean is clear and found to be statistically significant. Implications for possible transition-effect enhancements to pre-existing low-level convergence areas are briefly noted.