DoSTra: Discovering common behaviors of objects using the duration of staying on each location of trajectories

Since semantic trajectories can discover more semantic meanings of a user's interests without geographic restrictions, research on semantic trajectories has attracted a lot of attentions in recent years. Most existing work discover the similar behavior of moving objects through analysis of their semantic trajectory pattern, that is, sequences of locations. However, this kind of trajectories without considering the duration of staying on a location limits wild applications. For example, Tom and Anne have a common pattern of Home→Restaurant → Company → Restaurant, but they are not similar, since Tom works at Restaurant, sends snack to someone at Company and return to Restaurant while Anne has breakfast at Restaurant, works at Company and has lunch at Restaurant. If we consider duration of staying on each location we can easily to differentiate their behaviors. In this paper, we propose a novel approach for discovering common behaviors by considering the duration of staying on each location of trajectories (DoSTra). Our approach can be used to detect the group that has similar lifestyle, habit or behavior patterns and predict the future locations of moving objects. We evaluate the experiment based on synthetic dataset, which demonstrates the high effectiveness and efficiency of the proposed method.

My place: exploring children's place-related identities through reading and writing

This paper considers how children perceive and represent their placed-related identities through reading and writing. It reports on the findings of an 18-month interdisciplinary project, based at Cambridge University Faculty of Education, which aimed to consider children’s place-related identities through their engage- ment with, and creation of, texts. This paper will discuss the project, its interdisciplinary theoretical framework, and the empirical research we conducted with two classes in primary schools in Eastern England. A key text used in our research was My Place by Nadia Wheatley and Donna Rawlins. Drawing on our interdisciplinary theoretical framework, particularly Doreen Massey’s notion of place as a bundle of trajectories, and Louise Rosenblatt’s notion of the transaction between the reader and the text, this paper will examine pages from My Place, children talking about how this text connects with them, children talking about their sense of place, and maps and writing the children produced based on their place.

3D motion matching algorithm using signature feature descriptor

This paper introduces a basic frame for rehabilitation motion practice system which detects 3D motion trajectory with the Microsoft Kinect (MSK) sensor system and proposes a cost-effective 3D motion matching algorithm. The rehabilitation motion practice system displays a reference 3D motion in the database system that the player (patient) tries to follow. The player’s motion is traced by the MSK sensor system and then compared with the reference motion to evaluate how well the player follows the reference motion. In this system, 3D motion matching algorithm is a key feature for accurate evaluation for player’s performance. Even though similarity measurement of 3D trajectories is one of the most important tasks in 3D motion analysis, existing methods are still limited. Recent researches focus on the full length 3D trajectory data set. However, it is not true that every point on the trajectory plays the same role and has the same meaning. In this situation, we developed a new cost-effective method that only uses the less number of features called ‘signature’ which is a flexible descriptor computed from the region of ‘elbow points’. Therefore, our proposed method runs faster than other methods which use the full length trajectory information. The similarity of trajectories is measured based on the signature using an alignment method such as dynamic time warping (DTW), continuous dynamic time warping (CDTW) or longest common sub-sequence (LCSS) method. In the experimental studies, we applied the MSK sensor system to detect, trace and match the 3D motion of human body. This application was assumed as a system for guiding a rehabilitation practice which can evaluate how well the motion practice was performed based on comparison of the patient’s practice motion traced by the MSK system with the pre-defined reference motion in a database. In order to evaluate the accuracy of our 3D motion matching algorithm, we compared our method with two other methods using Australian sign word dataset. As a result, our matching algorithm outperforms in matching 3D motion, and it can be exploited for a base framework for various 3D motion-based applications at low cost with high accuracy.

Prediction of alcohol-related harm from controlled drinking stragegies and alcohol consumption trajectories

Aims To establish predictors of age 21 alcohol-related harm from prior drinking patterns, current levels of alcohol consumption and use of controlled drinking strategies.
Participants One thousand, five hundred and ninety-six students recruited from an initial sample of 3300 during their final year of high school in 1993.
Design Longitudinal follow-up across five waves of data collection.
Setting Post high school in Victoria, Australia.
Measurements Self-administered surveys examining a range of health behaviours, including alcohol consumption patterns and related behaviour.
Findings Drinking behaviours at age 21 were found to be strongly predicted by drinking trajectories established through the transition from high school. Multivariate regression analysis revealed that alcohol-related harms at age 21 were reduced where current levels of alcohol use fell within limits recommended in Australian national guidelines. After controlling for this effect it was found that the range of strategies employed by participants to control alcohol use maintained a small protective influence. Post-high-school drinking trajectories continued to demonstrate a significant effect after controlling for current behaviours. Findings revealed that over one quarter of males and females drank alcohol, but on a less-than-weekly basis. This pattern of alcohol use demonstrated considerable stability through the post-school transition and was associated with a low level of subsequent harm at age 21.
Conclusions Future research should investigate whether encouraging more Australian adolescents to drink alcohol on a less-than-weekly basis may be a practical intervention target for reducing alcohol-related harms.

Prediction of alcohol-related harm from controlled drinking strategies and alcohol consumption trajectories

Aims To establish predictors of age 21 alcohol-related harm from prior drinking patterns, current levels of alcohol consumption and use of controlled drinking strategies.

Participants One thousand, five hundred and ninety-six students recruited from an initial sample of 3300 during their final year of high school in 1993.

Design Longitudinal follow-up across five waves of data collection.

Setting Post high school in Victoria, Australia.

Measurements Self-administered surveys examining a range of health behaviours, including alcohol consumption patterns and related behaviour.

Findings Drinking behaviours at age 21 were found to be strongly predicted by drinking trajectories established through the transition from high school. Multivariate regression analysis revealed that alcohol-related harms at age 21 were reduced where current levels of alcohol use fell within limits recommended in Australian national guidelines. After controlling for this effect it was found that the range of strategies employed by participants to control alcohol use maintained a small protective influence. Post-high-school drinking trajectories continued to demonstrate a significant effect after controlling for current behaviours. Findings revealed that over one quarter of males and females drank alcohol, but on a less-than-weekly basis. This pattern of alcohol use demonstrated considerable stability through the post-school transition and was associated with a low level of subsequent harm at age 21.

Conclusions Future research should investigate whether encouraging more Australian adolescents to drink alcohol on a less-than-weekly basis may be a practical intervention target for reducing alcohol-related harms.

Psychosocial precursors and correlates of differing internalizing trajectories from 3 to 15 years

Psychosocial precursors and correlates of parent-reported internalizing behavior trajectories across the age span of 3–15 years were explored using a community-based cohort of Australian children. Six internalizing trajectories had previously been identified for both girls (N = 810) and boys (N = 874) in this sample, comprising stable low, high, decreasing, and increasing pathways. Infancy and toddler temperamental traits (inhibition/shyness, irritability), behavior problems, and parent–child relationship difficulties constituted significant risks for subsequent problematic internalizing profiles. Several gender-specific trends were evident, with temperamental reactivity and shyness, less optimal parenting, and peer difficulties more salient for girls on increasing trajectories whereas externalizing problems were more prominent among boys on increasing trajectories. Factors associated with recovery from elevated symptoms included higher levels of social competence, better parent and peer relations, and more positive school adjustment. Findings suggest that individual characteristics and relationship experiences may be involved in the development and course of internalizing problems.

Policy trajectories : treading the discursive path of policy analysis

This paper is concerned with theorising the nature of policy and its production. It takes as its starting point the work of Stephen Ball,1 particularly his writings within the pages of this journal (13(2), 1993)—later reprinted as Chapter 2 in Education Reform (1994a)—as well as his earlier writings in Politics and Policy Making in Education (1990) and Reforming Education and Changing Schools (Bowe, Ball & Gold, 1992). More broadly, the paper is located within a 'new' sociological interest in education policy often referred to as 'policy sociology'2 (Payne, Dingwall, Payne & Carter, 1981; Ozga, 1987, Ball, 1990; Bowe, Ball & Gold, 1992); a concern that is 'rooted in the social science tradition, historically informed and drawing on qualitative and illuminative techniques' (Ozga, 1987, p. 144) and 'united by the conviction that "things", especially policy discourse, must be pulled apart' (Troyna, 1994, p. 71) to determine whose interests they serve.

Precursors and correlates of anxiety trajectories from late childhood to late adolescence

The present research employed a prospective, multi-informant design to examine precursors and correlates of differing anxiety profiles from late childhood to late adolescence. The sample consisted of 626 boys and 667 girls who are participants in the Australian Temperament Project, a large, longitudinal, community-based study that has followed young people's psychosocial adjustment from infancy to adulthood. The present research analyzes data collected from the first 12 waves of data, from 4–8 months to 17 years. Parents, primary school teachers, maternal and child health nurses, and from the age of 11 onward, the young people themselves have provided survey data. Trajectory analyses revealed three distinct patterns of self-reported anxiety from late childhood to late adolescence, comprising low, moderate, and high (increasing) trajectories, which differed somewhat between boys and girls. A range of parent- and teacher-reported factors was found to be associated with these trajectories, including temperament style, behavior problems, social skills, parenting, negative family events, and peer relationships. Compared with male trajectories, female trajectories were associated with a greater variety of psychosocial variables (including parenting and externalizing problems), which may partially account for the higher prevalence of anxiety in adolescent girls compared with boys. Findings shed light on gender-specific pathways to anxiety and the need for comprehensive, integrative approaches to intervention and prevention programs.

Trajectories of desire in Genet and Wittig

At their most extreme Jean Genet and Monique Wittig stage revolutionary desire through their practice of language as material, embodied productivity in scenographies that decentre the ‘human' through a volatile mix of semiotic violence and iconoclastic eroticism. In fact, both writers strategically universalise homoerotic desire, plotting its trajectories to disrupt, deconstruct, or explode in parodic hilarity the cultural practices subtending patriarchal imperialism. This paper will be looking at the ceaseless productivity of desire in their texts as it moves through abjection and animal-becoming and finds serial ignition throughout its metonymic relay, arousing obstruction itself as its medium. Evidently these tropes and the concept of desire as productive come from Deleuze and Guattari (Deleuze & Gauttari 2008a; 2008b). While these subversive poetics are inseparable from the project to storm and overthrow what Timothy Mathews (Mathews 2000) calls the ‘image-fortresses' of patriarchal imperialism, they are less about utopian arrival than about the endlessly renewed performance of desire as metamorphic.

Ontogenetic development of migration : Lagrangian drift trajectories suggest a new paradigm for sea turtles

Long distance migration occurs in a wide variety of taxa including birds, insects, fishes, mammals and reptiles. Here, we provide evidence for a new paradigm for the determinants of migration destination. As adults, sea turtles show fidelity to their natal nesting areas and then at the end of the breeding season may migrate to distant foraging sites. For a major rookery in the Mediterranean, we simulated hatchling drift by releasing 288 000 numerical particles in an area close to the nesting beaches. We show that the pattern of adult dispersion from the breeding area reflects the extent of passive dispersion that would be experienced by hatchlings. Hence, the prevailing oceanography around nesting areas may be crucial to the selection of foraging sites used by adult sea turtles. This environmental forcing may allow the rapid evolution of new migration destinations if ocean currents alter with climate change.

A syntactic two-component encoding model for the trajectories of human actions

Human actions have been widely studied for their potential application in various areas such as sports, pervasive patient monitoring, and rehabilitation. However, challenges still persist pertaining to determining the most useful ways to describe human actions at the sensor, then limb and complete action levels of representation and deriving important relations between these levels each involving their own atomic components. In this paper, we report on a motion encoder developed for the sensor level based on the need to distinguish between the shape of the sensor's trajectory and its temporal characteristics during execution. This distinction is critical as it provides a different encoding scheme than the usual velocity and acceleration measures which confound these two attributes of any motion. At the same time, we eliminate noise from sensors by comparing temporal and spatial indexing schemes and a number of optimal filtering models for robust encoding. Results demonstrate the benefits of spatial indexing and separating the shape and dynamics of a motion, as well as its ability to decompose complex motions into several atomic ones. Finally, we discuss how this specific type of sensor encoder bears on the derivation of limb and complete action descriptions.

Trajectories and stability of self-reported short sleep duration from adolescence to adulthood

The trajectories and stability of self-reported sleep duration recorded at ages 13, 15, and 23 years on reported sleep duration at age 30 years among 1105 students (55% male) who participated in the Norwegian Longitudinal Health and Behaviour Study were examined. Questionnaire data were used to obtain demographic and sleep variables. Dichotomised short sleep duration was based on normative values and set as ≤8.5 h (age 13 years), ≤8 h (age 15 years) and ≤7 h (ages 23 and 30 years). Results indicated a significant overall reduction in total sleep duration (h per night) across age groups. Sleep duration (continuous) at age 15 and 23 years (whole group) was moderately but positively correlated with sleep duration at age 30 years (P < 0.01). When split by sex, at age 15 years, this association was present among females only (P < 0.01); however, at age 23 years, this association was present in both male and females (both P < 0.001). Categorical short sleep at age 23 years (whole group) was associated with short sleep at age 30 years (unadjusted odds ratio = 3.67, 95% confidence interval 2.36-5.69). Following sex stratification, this effect was significant for both males (unadjusted odds ratio = 3.77, 95% confidence interval: 2.22-6.42) and females (unadjusted odds ratio = 2.71, 95% confidence interval: 1.46-5.04). No associations were noted for categorical short sleep at ages 13 or 15 years, and subsequent short sleep at 30 years. Habitual short sleep duration during middle adulthood is not sustained from the time of early adolescence. Rather, these trends appear to be formed during early adulthood.