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Augmented Reality focuses on the enrichment of the user's natural field of view by consistent integration of text, symbols and interactive three-dimensional objects in real time. Placing virtual objects directly into the user's view in a natural context empowers highly dynamic applications. On the other hand, this necessitates deliberate choice of information design and density, in particular for deployment in hazardous environments like military combat scenarios. As the amount of information needed is not foreseeable and strongly depends on the individual mission, an appropriate system must offer adequate adaptation capabilities. The paper presents a prototypical, vehicle-mountable Augmented Reality vision system, designed for enhancing situation awareness in stressful urban warfare scenarios. Tracking, as one of the most crucial challenges for outdoor Augmented Reality, is accomplished by means of a Differential-GPS approach while the type of display to attach can be modified, ranging from ocular displays to standard LCD mini-screens. The overall concept also includes envisioning of own troops (blue forces), for which a multi-sensor tracking approach has been chosen. As a main feature, the system allows switching between different information categories, focusing on friendly, hostile, unidentified or neutral data. Results of an empirical study on the superiority of an in-view navigation cue approach conclude the paper.  相似文献   
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Jan Van Bavel 《Demography》2010,47(2):439-458
Theory suggests that the field of study may be at least as consequential for fertility behavior as the duration and level of education. Yet, this qualitative dimension of educational achievement has been largely neglected in demographic studies. This article analyzes the mechanisms relating the field of study with the postponement of motherhood by European college-graduate women aged 20–40. The second round of the European Social Survey is used to assess the impact of four features of study disciplines that are identified as key to reproductive decision making: the expected starting wage, the steepness of the earning profile, attitudes toward gendered family roles, and gender composition. The results indicate that the postponement of motherhood is relatively limited among graduates from study disciplines in which stereotypical attitudes about family roles prevail and in which a large share of the graduates are female. Both the level of the starting wage and the steepness of the earning profile are found to be associated with greater postponement. These results are robust to controlling for the partnership situation and the age at entry into the labor market.  相似文献   
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When parents divorce, grandparents can play a supportive role in the lives of their grandchildren, but a parental divorce may also put grandchild–grandparent ties under pressure. In this study the authors investigated how grandchildren of married and divorced parents differ in the frequency of face‐to‐face contacts with grandparents and how this is mediated by postdivorce residence arrangements. Based on the multi‐actor survey “Divorce in Flanders,” they used reports of contact provided by more than 1,000 grandchildren and compared them with more than 1,100 grandparent reports for validation. The results showed that grandchildren from divorced parents have fewer contacts with their grandparents than grandchildren whose parents are married but that it is the postdivorce residence arrangement of grandchildren that produces this result. When grandchildren live with their divorced father or in a shared residence arrangement, they even see paternal grandparents more often than grandchildren with married parents.  相似文献   
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The aim of this study was to unravel the interrelatedness of friendship and help, and to examine the characteristics of friendship and help networks. The effects of mutual versus one‐sided help relations on friendship initiation and maintenance, and vice versa, were examined. Friendship and help networks were analyzed (N = 953 students; 41 classrooms; Mage = 12.7). The results illustrate that friendship and help networks show some similarities, but only partly overlap and have distinct characteristics. Longitudinal multiplex social network analyses showed that mutual help was important for the maintenance of friendship, but not for the initiation of friendship. Further, particularly mutual friendships provided a context in which help took place. Implications of these findings are discussed.  相似文献   
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Parental psychopathology and parenting behavior are known to be related to adolescents depression and anxiety, but unique roles of mothers and fathers are not clear. Our aim was to examine the relation of maternal and paternal psychopathology, emotional support, and respect for autonomy, and their interaction to depression and anxiety symptoms in adolescents. In total, 142 female adolescents participated, together with 138 mothers and 113 fathers. Data were analyzed using latent growth curve modeling. Paternal emotional support was negatively related to adolescent baseline level of depression and anxiety symptoms. Further, we found that there was a positive association between respect for autonomy and depression symptoms in adolescents for higher levels of paternal symptoms of psychological problems.  相似文献   
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The private nature of psychosexual functioning leads adolescents and their parents to have different perspectives, which highlights studying parent–child informant discrepancies in this domain. We investigated informant discrepancy in psychosexual functioning, using the self‐report and parent report versions of the Teen Transition Inventory (TTI), of adolescents with autism spectrum disorder (ASD; 136 parent–child dyads) compared to adolescents from the general population (GP; 70 parent–child dyads). Significantly larger informant discrepancies exist in ASD dyads than GP dyads in most domains of psychosexual functioning, except for Body image, Sexual behavior, and Confidence in the future. It is important to use and pay attention to both informants, as discrepancies are relevant for both research and clinical practice regarding psychosexual functioning.  相似文献   
59.
In this paper, we revisit the construction of confidence intervals for extreme quantiles of Pareto-type distributions. A novel asymptotic pivotal quantity is proposed for these quantile estimators, which leads to new asymptotic confidence intervals that exhibit more accurate coverage probability. This pivotal quantity also allows for the construction of a saddle-point approximation, from which a second set of new confidence intervals follows. The small-sample properties and utility of these confidence intervals are studied using simulations and a case study from insurance.  相似文献   
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For large cohort studies with rare outcomes, the nested case-control design only requires data collection of small subsets of the individuals at risk. These are typically randomly sampled at the observed event times and a weighted, stratified analysis takes over the role of the full cohort analysis. Motivated by observational studies on the impact of hospital-acquired infection on hospital stay outcome, we are interested in situations, where not necessarily the outcome is rare, but time-dependent exposure such as the occurrence of an adverse event or disease progression is. Using the counting process formulation of general nested case-control designs, we propose three sampling schemes where not all commonly observed outcomes need to be included in the analysis. Rather, inclusion probabilities may be time-dependent and may even depend on the past sampling and exposure history. A bootstrap analysis of a full cohort data set from hospital epidemiology allows us to investigate the practical utility of the proposed sampling schemes in comparison to a full cohort analysis and a too simple application of the nested case-control design, if the outcome is not rare.

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