Heading south with a north-up map: A choice processing analysis of map alignment effects

This study employed an information accumulation model of choice reaction times to investigate alignment effects in mental representations of maps. University students studied a map from a single orientation (with north at the top). In a subsequent two-choice reaction time task, the students’ spatial knowledge of the map was assessed employing spatial left/right judgments, which were made from imagined perspectives that were either north-aligned or south-aligned. Data showed a standard alignment effect, favoring north- over south-aligned trials. To examine the locus of this effect, data were fit using the Linear Ballistic Accumulator (LBA) model of speeded decisions (Brown & Heathcote, 2008). Of interest were three model parameters: drift rate, the speed at which evidence accumulates toward a response; response threshold, the amount of evidence demanded from the decision maker before selecting a response; and non-decision time, the time consumed by pre- and postdecisional processes. The best-fitting model suggested that non-decision time accounted for the alignment effect. The difference in non-decision time between north and south-aligned judgments suggests a mental alignment stage on south-aligned trials, accounting for the longer reaction times for judgements misaligned with the presented north orientation of the map.     

Human Four-Dimensional Spatial Judgments of Hyper-Volume

The dimensionality limitation of human spatial representations has been a long-lasting, unsolved issue in psychology, mathematics, and philosophy. The present study examined the possibility of human four-dimensional spatial representations using a spatial judgment task on hyper-volume, a novel property unique to higher dimensional space. Observers studied visual simulations of random wireframe hyper-tetrahedrons (4-simplexes) rotating around the y-z plane and judged their hyper-volume by adjusting the size of a 4-D block. Multiple regression analyses showed a significant correlation between the responses and the actual hyper-volume but not the definition-based, lower-dimensional cues such as the mean 3-D volume, providing empirical evidence of human 4-D spatial representations that can support judgments of certain novel, high-dimensional properties.     

Function,geometry and spatial prepositions: Three experiments

In this paper the results of three experiments are reported whichaddress the issue of the relative extent to which functionalrelations versus geometric relations affect spatial language. Theexperiments examine the role of a discourse context on the useand rating of the preposition in to describe a visual scenewhere the constraint of spatial containment between figure(object located) and ground (reference object) does not hold. Allthree experiments demonstrate that in is used more andrated to be significantly more appropriate in a functionalcontext than in a no context condition. The implications of thesestudies for spatial language and spatial representation arediscussed.     

Spatial Influence of Environmental Axes in a Baseball Field

Abstract

We investigated the influence of environmental axes in a baseball field. In Experiment 1, participants walked either a path in the prototypical orientation (home plate to second base) or one which was rotated 225°. Recall for object locations was best when participants imagined themselves aligned with axes salient from the experienced orientation. In Experiment 2, when learning was through a route text, there was less of an influence of environmental axes. In Experiment 3, when participants walked both paths, memories were good for the atypical orientation, suggesting that task-specific spatial cues can be more influential than a prior conceptual north.     

Influences of Form and Function on the Acceptability of Projective Prepositions in Swedish

Abstract

Projective prepositions express the relation between two objects by referring to a direction in space and have traditionally been regarded as expressing purely geometric relations. Recent studies have shown that the appropriateness of English and Spanish projectives also depends on functional relations between objects. This study investigates if the acceptability of the Swedish projectives över, under, ovanför and nedanför are influenced by functional factors as well, and whether över and under are differentially influenced by function than ovanför and nedanför, as has been shown for their English cognates. It also investigates how the shape and parts of the related objects influence their functional interaction, and thereby the acceptability of the prepositions. This is done with respect to the predictions of the AVS-model, a model of the perceptual processes underlying the apprehension of projectives, which takes both the geometric and the functional relation between objects into account. It was found that acceptability judgments about the prepositions are influenced by function as their corresponding English and Spanish prepositions. The acceptability of över was more sensitive to function than ovanför, whereas under and nedanför were not differentially influenced by function, as has been shown for Spanish. It was further found that the shape and parts of both of the related objects influence acceptability regions associated with the prepositions in predictable ways, as functional interactions between objects largely depend on their parts. The results finally show that the AVS-model needs to be further developed in order to account for the form and function of the located object.     

Context Affects Scale Selection for Proximity Terms

Abstract

Spatial proximity terms, such as near and far, communicate information regarding the distance in which a “located” object can be found with respect to a “reference” object. The present paper investigates whether people take into account the location of an object extraneous to the located object and reference object pair, when setting the scale for proximity language judgements. Across three experiments participants rated the appropriateness of near and far to describe spatial scenes that included a third (distractor) object positioned the same distance as the located object from the reference object, but at varying distances from the located object. The results show that the presence of other spatial relations affects scale setting, resulting in differences in appropriateness ratings for those spatial terms.     

Young Children's Perception of Diagrammatic Representations

Diagrams and pictorial representations are common in children's lives and require abstraction away from visual perception. In three experiments, we investigated 4- to 8-year-olds’ comprehension of such representations. In Experiment 1 (N = 80), children were shown photographs of geometric objects and asked to choose the corresponding line drawing from among sets of four, or vice versa. Results showed considerable developmental progression, especially around age 6. Experiment 2 (N = 16) ruled out that 4-year-olds’ difficulties were due to problems with the visual matching task itself. Experiment 3 (N = 32) showed comparable performance for matching diagrams to 3D objects rather than to photographs. Findings suggest increasing understanding of diagrammatic representations around the time of school entry.     

Probability of Collision Error Analysis

The decision for the International Space Station (ISS) to maneuver to avoid a potential collision with another space object will be based on the probability of collision, P _C. The calculation of P _C requires the covariance of both objects at conjunction. It is well known that the covariance computed by US Space Command is optimistic (too small), especially at altitudes where atmospheric drag is the dominant perturbation, because its computation assumes there are no dynamic model errors. In this paper the effect of errors in the covariance on P _C and the sensitivity of P _C to the encounter geometry are investigated.     

熔融沉积成型连续碳纤维增强尼龙蜂窝芯材的压缩特性

采用熔融沉积成型方法成形了连续碳纤维增强尼龙复合材料蜂窝芯材,并对不同测试方向的静态单轴压缩特性进行了表征分析,着重关注不同测试方向熔融沉积成形蜂窝芯材平面静态压缩破碎行为和能量吸收行为,并与纯聚合物基体进行对比。结果表明:X_1方向的压缩平台区域的力-位移曲线更加平滑稳定,且载荷值稍高于X_2方向,因此X_1方向更适用于能量吸收应用;此外,连续纤维的增强作用可使蜂窝芯材的平台载荷值得到明显提升。研究结果为连续纤维增强聚合物复合材料的空间增材制造提供理论基础。     

Multiple Systems for Spatial Imagery: Transformations of Objects and Bodies

Problem-solving often requires imagining spatial changes. Object-based transformations allow imagining an object in a different orientation. Perspective transformations allow imagining changes in one's viewpoint. Three experiments tested the hypothesis that these two transformations are dissociable and specialized for different situations, by manipulating instructions and task parameters and measuring response times, errors, and introspective reports. Human experience with small objects such as telephones and clothes irons consists mostly of manipulation or observed manipulation, which is characterized by object-based transformations. Consistent with this experience, when participants made judgments about small manipulable objects, they showed a strong tendency to use object-based transformations. Experience with human bodies is more varied, including both object-like interactions and interactions in which one must estimate another's perspective. Accordingly, when making judgments about pictures of bodies, participants' selection of a spatial transformation depended on the type of judgment that needed to be made. When instructions violated these natural mappings, performance was impaired. These data argue for the view that multiple spatial transformation systems evolved to solve different spatial reasoning problems.     

The conventionality of pictorial representation in interstellar messages

Pictorial messages have previously been advocated for interstellar communication because such messages are presumed to be capable of presenting information in a non-arbitrary and easily intelligible manner. In contrast to this view, pictorial messages actually represent information in a partially conventional way. This point is demonstrated by examining pictorial representations of human beings from a range of cultures. While such representations may be understood quite readily by individuals familiar with the conventions of a particular culture, to the uninitiated outsider, such representations can be unintelligible. In spite of the partially arbitrary nature of pictorial representation, we may be able to construct messages that would teach extraterrestrial intelligence (ETI) some of the conventions by which we view pictures. One such approach is to pair numerical information about geometrical objects with pictorial representations of the same objects. Problems of conventionality can also be addressed in part through use of (1) multiple representations of the same object, (2) contextual cues, (3) three- and four-dimensional representations and (4) non-visual representations.     

Prioritized Spatial Updating in the Intrinsic Frame of Reference

In order to maintain valid situation awareness, people need to update the spatial representations of their surroundings as objects, including themselves, move. The present study investigates the properties of spatial updating in the intrinsic frame of reference, where spatial relations are represented with respect to an external object (other than the viewer self) with an intrinsic reference direction. Three experiments were conducted using a task of direction pointing. It was found that given a relatively stable intrinsic reference direction, responses to a small number of salient objects were faster than responses to non-salient objects (Experiment 1 and Experiment 3). The salience effect disappeared when the intrinsic reference direction was no longer stable (Experiment 2). Furthermore, all three experiments revealed a type of orientation dependence similar to that found in egocentric spatial updating. Our results indicate that spatial updating in the intrinsic reference system can be easy only if a fixed reference direction is maintained and the number of objects that need to be tracked is limited.     

Is Route Learning More Than Serial Learning?

Abstract

The nature of route learning in terms of the memorizing of landmarks was investigated. In Experiment 1, participants memorized landmarks while being guided through a computer-simulated hallway (dynamic, with spatial context), or while viewing the landmarks one by one in front of a black background (static, without context). Two more conditions completed the 2 × 2 design. One condition preserved the dynamic landmark viewing properties (observers approached each object, passed it, turned to the next object, and so on), but the background was black (dynamic, without context). In the other condition the observer saw a stationary display of each object within a hallway, but did not approach the object (static, with context). Serial recall was much better after viewing the landmarks in the dynamic presentation format with spatial context than in the other conditions. Experiment 2 showed that the superior performance in the dynamic condition with context was abolished when all hallway segments were equally long. This implies that metric information is a component of route knowledge at a very early stage, which is incompatible with the dominant framework, but is compatible with the alternative framework for spatial microgenesis.     

Assessment of between-floor structural and topological properties on cognitive map development in multilevel built environments

The present study investigated cognitive map development in multilevel built environments. Three experiments were conducted in complex virtual buildings to examine the effects of five between-floor structural factors that may impede the accuracy of humans’ ability to build multilevel cognitive maps. Results from Experiments 1 and 2 (of three experiments) revealed that difficulties in developing multilevel cognitive maps are not solely caused by the z-axis offset, as is suggested in the literature, but are due to the factorial combination of a between-floor overlap and a z-axis offset. Results from Experiment 2 showed that this process becomes substantially more difficult when the reference directions between different floors have an angular offset from each other. Finally, results from Experiment 3 demonstrated that confusing between-floor heading shifts in aligned buildings did not make it reliably harder to build multilevel cognitive maps. The implications of these findings are discussed in terms of theories of mental representations in multilayered three-dimensional spaces, as well as for architectural design.     

Verb Semantics Affects the Interpretation of Spatial Prepositions

Abstract

Spatial prepositions, more specifically projective prepositions, such as in front of or behind can be interpreted in different ways. Their interpretation depends on the spatial perspective taken as the basis for determining the reference frame's orientation. In 3 series of placement experiments with German speakers, we examined whether the interpretation of projective prepositions in a motion context is affected by the verb used in a spatial instruction. Results suggest that verb semantics is a factor accounting for previously observed seemingly social-situational differences in the interpretation of projective prepositions. Specifically, the findings indicate that, relative to a car as reference object, the semantic aspect of motion interruption associated with some verbs leads to a higher proportion of deictic interpretations determined by the direction from which one is approaching the car. This verb effect on the interpretation of spatial prepositions can be explained by an activation of the temporal dimension through stop-implying verbs, which is integrated into the spatial situation model of the perceived dynamic scene making the deictic frame of reference more compatible. The experimental evidence also shows that verb semantics can account for previously unexplained cross-linguistic differences, and is related to patterns concerning the prepositional inventory of languages.     

Experiments on velocity augmentation of spherical flames by grids

Using spherical wire mesh screens with a wire diameter d and a mesh size l, an experimental study was carried out involving homogeneous mixtures of propane/air, ethylene/air, acetylene/air and with oxygen enriched air. Streak photographs of the processes were taken, yielding information on the flame propagation speeds inside and outside the screen. The ratio of the two speeds immediately before and after crossing the screen, α, can be interpreted as practically equivalent (for the same “heat release”) to the ratio of flame velocities relative to the unburned gas, i.e. Values of (α − 1) are correlated with the Reynolds number based on the wire thickness d, density and viscosity of the unburned gas and flame propagation speed inside the wire mesh. The experiments were repeated with two and three spheres of different diameters, e.g. inner screen 9 cm in diameter and outer screen 18 cm in diameter or three screens, 9, 13.5 and 18 cm, respectively. The second screen usually added a factor of 2 on the value of α. The third screen produced very little additional effect. The highest value of α we ever obtained for mixtures with air was about 12 (for acetylene/air). With oxygen enriched air the situation is quite different. If the flame velocity of the laminar flame relative to the unburned gas exceeds 2 m/sec, the value of α may increase up to a level corresponding to detonation.     

Mechanics of Zero Gravity and Gravitationally Sensitive Systems (First Issue)

This issue of the journal contains papers with the results of studying gravitationally sensitive systems and processes under conditions of microgravity aboard the Mirorbital complex. This is one of the most difficult field of space research whose difficulties are due to both complexity of the object of investigations (since the class of gravitationally sensitive systems and processes is fairly wide, and some of them are not sufficiently studied even under terrestrial conditions) and necessity of using expensive instrumentation and carrying out long-term experiments. However, studying the new mechanical state of weightlessness is inevitable in space exploration. In addition, in some cases it can provide for a new knowledge about the fundamental laws of nature. By virtue of the above reasons, the experiments on microgravity are well presented in the research program onboard the International Space Station.There is a long tradition in this field of research in Russia, and the experience of Russian scientists (a part of which is presented in the papers of this issue) allows them to pass on to the next, better technically equipped, stage of investigations in cooperation with the scientists from other countries.This issue is prepared by an initiative of the subsection Mechanics of zero gravity and gravitationally sensitive systemsof the Coordination Scientific and Technical Council (CSTC) of the Russian Agency for Aviation and Space Flights (Rosaviakosmos).     

月球钻取采样钻头结构参数对力学性能的影响

基于对螺旋钻头的输出月壤阻力、驱动力矩及月壤失效区的分析,建立了钻头的力学模型,该模型综合考虑切削具内外侧面与月壤之间的压力及摩擦力,考虑月壤侧向失效面的面载荷对钻头切削具周向力矩、总功耗及月壤失效距离的影响,数值仿真与试验结果校验了模型的正确性。在数值仿真过程中采用深层月壤本构关系的Mohr-Coulomb模型,使仿真更加符合月壤内摩擦角大于22°的真实情况。利用该模型分析并获得了钻头结构参数对切削具功耗和失效距离的影响规律,以钻头功耗最小为优化目标,用遗传算法对钻头结构参数进行了优化,优化结果降低了钻探过程中的烧钻风险。可为钻取式自动采样机构的钻头设计提供理论依据。     

Revisiting Perspective-Taking: Can People Maintain Imagined Perspectives?

Abstract

Three experiments were conducted to examine whether people can adopt and maintain imagined perspectives in the absence of target information. The task used entailed providing information about an imagined perspective in advance of target information to examine whether this would facilitate perspective-taking performance and reduce or eliminate alignment effects that are commonly reported in the literature. The three experiments employed different types of spatial environments: an environment learned from navigating a computer screen (Experiment 1), and an immersive environment that was either remote (Experiment 2) or immediate (Experiment 3) at the time of retrieval. Across the three experiments, results showed that information about an imagined perspective can be utilized ahead of target information. Furthermore, they suggested that alignment effects can be reduced as a result of processing information about perspective ahead of target information, but only when reasoning about specific nonimmediate spatial relations (Experiments 1 and 2). Results are discussed in connection with previous findings on spatial updating and the organizational structure of spatial memory.