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221.
Monocular approaches to simultaneous localization and mapping (SLAM) have recently addressed with success the challenging problem of the fast computation of dense reconstructions from a single, moving camera. Thus, if these approaches initially relied on the detection of a reduced set of interest points to estimate the camera position and the map, they are currently able to reconstruct dense maps from a handheld camera while the camera coordinates are simultaneously computed. However, these maps of 3-dimensional points usually remain meaningless, that is, with no memorable items and without providing a way of encoding spatial relationships between objects and paths. In humans and mobile robotics, landmarks play a key role in the internalization of a spatial representation of an environment. They are memorable cues that can serve to define a region of the space or the location of other objects. In a topological representation of the space, landmarks can be identified and located according to its structural, perceptive or semantic significance and distinctiveness. But on the other hand, landmarks may be difficult to be located in a metric representation of the space. Restricted to the domain of visual landmarks, this work describes an approach where the map resulting from a point-based, monocular SLAM is annotated with the semantic information provided by a set of distinguished landmarks. Both features are obtained from the image. Hence, they can be linked by associating to each landmark all those point-based features that are superimposed to the landmark in a given image (key-frame). Visual landmarks will be obtained by means of an object-based, bottom-up attention mechanism, which will extract from the image a set of proto-objects. These proto-objects could not be always associated with natural objects, but they will typically constitute significant parts of these scene objects and can be appropriately annotated with semantic information. Moreover, they will be affine covariant regions, that is, they will be invariant to affine transformation, being detected under different viewing conditions (view-point angle, rotation, scale, etc.). Monocular SLAM will be solved using the accurate parallel tracking and mapping (PTAM) framework by Klein and Murray in Proceedings of IEEE/ACM international symposium on mixed and augmented reality, 2007. 相似文献
222.
Recent studies on the conceptualization of abstract concepts suggest that the concept of time is represented along a left-right horizontal axis, such that left-to-right readers represent past on the left and future on the right. Although it has been demonstrated with strong consistency that the localization (left or right) of visual stimuli could modulate temporal judgments, results obtained with auditory stimuli are more puzzling, with both failures and successes at finding the effect in the literature. The present study supports an account based on the relative relevance of visual versus auditory-spatial information in the creation of a frame of reference to map time: The auditory location of words interacted with their temporal meaning only when auditory information was made more relevant than visual spatial information by blindfolding participants. 相似文献
223.
We studied the acquisition of the ordinal meaning of number words and examined its development relative to the acquisition of the cardinal meaning. Three groups of 3-, 4-, and 5-year-old children were tested in two tasks requiring the use of number words in both cardinal and ordinal contexts. Understanding of the counting principles was also measured by asking the children to assess the correctness of a cartoon character's counting in both contexts. In general, the children performed cardinal tasks significantly better than ordinal ones. Tasks requiring the production of the number for a given quantity or position were solved more accurately than those testing the ability to select a set of n objects or the object in the nth position. Different profiles were obtained for the principles; those principles shared by the two contexts were mastered earlier in the cardinal context. Regarding order (ir)relevance, older children adhered to rigid ways of counting, producing better results in the ordinal context and incorrect rejections in the cardinal trials. Altogether, our data indicate that the acquisitions of cardinal and ordinal meanings of numbers are related, and cardinality precedes the development of ordinality. 相似文献
224.
Pilar Carrera Dolores Muñoz Amparo Caballero Itziar Fernández Dolores Albarracín 《Journal of experimental social psychology》2012,48(5):1196-1200
Three studies examined how the use of the present versus the past tense in recalling a past experience influences behavioral intentions. Experiment 1 revealed a stronger influence of past behaviors on drinking intentions when participants self-reported an episode of excessive drinking using the present tense. Correspondingly, there was a stronger influence of attitudes towards excessive drinking when participants self-reported the episode in the past tense. Experiments 2 and 3 liked this effect to changes in construal level (Liberman, Trope, & Stephan, 2007; Trope & Liberman, 2003), with the present tense being similar to a concrete construal level and the past tense being similar to an abstract construal level. 相似文献
225.
Credé M Harms P Niehorster S Gaye-Valentine A 《Journal of personality and social psychology》2012,102(4):874-888
Researchers often use very abbreviated (e.g., 1-item, 2-item) measures of personality traits due to their convenience and ease of use as well as the belief that such measures can adequately capture an individual's personality. Using data from 2 samples (N = 437 employees, N = 355 college students), we show that this practice, particularly the use of single-item measures, can lead researchers to substantially underestimate the role that personality traits play in influencing important behaviors and thereby overestimate the role played by new constructs. That is, the use of very short measures of personality may substantially increase both the Type 1 and Type 2 error rates. We argue that even slightly longer measures can substantially increase the validity of research findings without significant inconvenience to the researcher or research participants. 相似文献
226.
Penelo E Granero R Fernández-Aranda F Aymamí N Gómez-Peña M Moragas L Santamaría JJ Custal N Menchón JM Jiménez-Murcia S 《Psychological reports》2012,110(2):555-570
The study compared clinical, psychopathological, and personality profiles between immigrants and Spanish native-born pathological gambling patients. A total of 1,601 native-born and 133 immigrant patients attending treatment at a specialized hospital unit were administered a battery of questionnaires during clinical assessment. Outcome measures were compared between both groups and the incremental predictive accuracy of the area of origin was examined using a regression model. Native-born Spaniards showed a mean 2.6 yr. greater duration of the disorder, while immigrants scored higher on South Oaks Gambling Screen, frequency of going to casinos, and total money spent (in a single day and/or to recover losses). General psychopathology and personality scores did not differ between the cohorts. However, immigration from Asia had a statistically significantly incremental validity for pathological gambling in South Oaks Gambling Screen scores. Both cohorts shared more similarities than differences in their gambling profiles. 相似文献
227.
István Aranyosi 《Ratio》2012,25(3):249-259
The prospect, in terms of subjective expectations, of immortality under the no‐collapse interpretation of quantum mechanics is certain, as pointed out by several authors, both physicists and, more recently, philosophers. The argument, known as quantum suicide, or quantum immortality, has received some critical discussion, but there hasn't been any questioning of David Lewis's point that there is a terrifying corollary to the argument, namely, that we should expect to live forever in a crippled, more and more damaged state, that barely sustains life. This is the prospect of eternal quantum torment. Based on some empirical facts, I argue for a conclusion that is much more reassuring than Lewis's terrible scenario. 1 相似文献
228.
229.
The house mouse (Mus musculus) and the mound‐building mouse (M. spicilegus) differ in their mating and social systems. The M. musculus is polygynous and females tend to breed cooperatively while M. spicilegus is known to be monogamous and famous for its unique cooperative behavior; the communal overwintering. Mus spicilegus is considered as a highly aggressive species in the genus Mus. In the present study, we attempted to analyze the development of aggressive and sociable behavior in these species and to discover how familiarity with the target moderates the development of sociable and aggressive behaviors and moderates the differences between the species. Dyadic social interaction tests in neutral cages were performed on 21‐, 60‐, and 120‐day‐old mice of both genders and both species. Each individual was tested against a sibling and an unfamiliar individual at all three ages. Our results showed that the development of aggressive and sociable behavior with age differed between the species and sexes; however, familiarity with the other mouse moderated the effect of species on aggression. At 21 days, both genders of M. spicilegus were more aggressive against strangers than siblings. This became true of both species at 60 days. When facing a stranger, both sexes of M. spicilegus were more aggressive than M. musculus at 120 days. However, when facing a sibling, neither gender of M. spicilegus was more agonistic than M. musculus, indicating that either kinship or early social experiences elicit tolerance. Aggr. Behav. 38:288‐297, 2012. © 2012 Wiley Periodicals, Inc. 相似文献
230.
Miia Sainio René Veenstra Gijs Huitsing Christina Salmivalli 《Aggressive behavior》2012,38(6):442-455
Risk factors for same‐ and other‐sex victimization were examined in a longitudinal data set involving 9‐ to 14‐year‐old students. The findings regarding same‐sex victimization supported the view that bullies select personally and interpersonally vulnerable targets in order to maximize their gains in status while minimizing loss of affection within their same‐sex peer group. Although low self‐esteem was a joint predictor of same‐ and other‐sex victimization, rejection and lack of friends among other‐sex peers failed to predict victimization by other‐sex bullies, and being perceived as popular among other‐sex peers increased the risk. Although the findings suggests that interpersonal risk factors for other‐sex victimization differ from those found for same‐sex victimization, they do not provide strong support for heterosexual interest being the basis for other‐sex target selection, as suggested by some previous literature. As about half of the study participants were involved in the KiVa antibullying program, we had the possibility to examine whether the program effects were similar for same‐ and other‐sex victimization. It turned out that in middle schools the program decreased only same‐sex victimization, whereas in elementary school the decrease was observed regardless of the sex composition of bully–victim dyads. Aggr. Behav. 38:442‐455, 2012. © 2012 Wiley Periodicals, Inc. 相似文献