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191.
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
192.
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
193.
Vergés A Jackson KM Bucholz KK Grant JD Trull TJ Wood PK Sher KJ 《Journal of abnormal psychology》2012,121(2):511-523
Epidemiological studies have consistently demonstrated that heavy alcohol use and alcohol dependence (AD) tend to increase in adolescence and emerging adulthood and then show a large decline in the late 20s, a phenomenon called maturing out. This decline has been explained as an effect of "role incompatibility" in which involvement in new roles and activities interferes with a heavy drinking lifestyle. However, maturing out has been conceived mostly as a decrease in offset, with little attention paid to reductions in new onset or recurrence across decades of life. Moreover, although role incompatibility processes have been studied with young samples, little is known about the effect of life transitions (e.g., marriage, parenthood, changes in employment status) on AD later in life and whether similar effects are observed. Using longitudinal data from the National Epidemiologic Survey on Alcohol and Related Conditions, a nationally representative epidemiologic survey, we examined the patterns of stability and change in AD across the life span and the differential effect of life transitions on AD across different age strata. Results showed that persistence of AD tended to increase with age, although not dramatically, and that onset and recurrence tended to decrease with age. Moreover, the effects of life transitions on the course of AD varied across the life span and were different for men and women. These results indicate that life transitions differentially affect the patterns of stability and change in younger versus older people, have a different impact for men and women, and highlight the need to consider the unique aspects of each stage of adult development on the course of AD. 相似文献
194.
Michelle vanDellen Matthew Sanders Gráinne M. Fitzsimons 《Journal of experimental social psychology》2012,48(5):1100-1105
People often encounter self-control challenges in complex everyday environments in which objects that promote a given goal (e.g., to eat healthily) are mixed together with objects that obstruct that goal. For example, healthy and unhealthy food choices are often mixed together in restaurant menus. Because local processing facilitates attention to low-level details, we expect that it may play an important role in these complex situations. In the present studies, we test the hypothesis that local processing supports self-control when goal items and temptations are contextually paired. As predicted, our findings revealed that local processing (relative to global processing) increased evaluations of healthy items when those items were presented together with unhealthy items. As hypothesized, this effect of local processing only occurred when healthy and unhealthy foods were presented as complementary – not competing – options, suggesting that local processing may increase evaluations of healthy options by decreasing the extent to which individuals accept environmental cues that healthy and unhealthy foods belong together. These findings support recent research demonstrating that despite strong evidence of the advantages of global processing for self-control, local processing may also support self-control efforts in some important everyday situations. 相似文献
195.
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
196.
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
197.
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
198.
An effect algebra is a partial algebraic structure, originally formulated as an algebraic base for unsharp quantum measurements. In this article we present an approach to the study of lattice effect algebras (LEAs) that emphasizes their structure as algebraic models for the semantics of (possibly) non-standard symbolic logics. This is accomplished by focusing on the interplay among conjunction, implication, and negation connectives on LEAs, where the conjunction and implication connectives are related by a residuation law. Special cases of LEAs are MV-algebras and orthomodular lattices. The main result of the paper is a characterization of LEAs in terms of so-called Sasaki algebras. Also, we compare and contrast LEAs, Hájek??s BL-algebras, and the basic algebras of Chajda, Hala?, and Kühr. 相似文献
199.
200.
We argue that indeterminate probabilities are not only rationally permissible for a Bayesian agent, but they may even be rationally required. Our first argument begins by assuming a version of interpretivism: your mental state is the set of probability and utility functions that rationalize your behavioral dispositions as well as possible. This set may consist of multiple probability functions. Then according to interpretivism, this makes it the case that your credal state is indeterminate. Our second argument begins with our describing a world that plausibly has indeterminate chances. Rationality requires a certain alignment of your credences with corresponding hypotheses about the chances. Thus, if you hypothesize the chances to be indeterminate, your will inherit their indeterminacy in your corresponding credences. Our third argument is motivated by a dilemma. Epistemic rationality requires you to stay open-minded about contingent matters about which your evidence has not definitively legislated. Practical rationality requires you to be able to act decisively at least sometimes. These requirements can conflict with each other-for thanks to your open-mindedness, some of your options may have undefined expected utility, and if you are choosing among them, decision theory has no advice to give you. Such an option is playing Nover and Hájek??s Pasadena Game, and indeed any option for which there is a positive probability of playing the Pasadena Game. You can serve both masters, epistemic rationality and practical rationality, with an indeterminate credence to the prospect of playing the Pasadena game. You serve epistemic rationality by making your upper probability positive-it ensures that you are open-minded. You serve practical rationality by making your lower probability 0-it provides guidance to your decision-making. No sharp credence could do both. 相似文献