Bi-objective bundle adjustment: towards large-scale visual sea-floor mapping with a minimal sensor suite

Visual sea-floor mapping is a rapidly growing application for Autonomous Underwater Vehicles (AUVs). AUVs are well-suited to the task as they remove humans from a potentially dangerous environment, can reach depths human divers cannot, and are capable of long-term operation in adverse conditions. The output of sea-floor maps generated by AUVs has a number of applications in scientific monitoring: from classifying coral in high biological value sites to surveying sea sponges to evaluate marine environment health.

Impact of physical, psychological, and sexual violence on social adjustment of school children in India

and sexual violence on the social adjustment of Grade 8 and 9 school children in the state of Tripura, India. The study participants, 160 boys and 160 girls, were randomly selected from classes in eight English and Bengali medium schools in Agartala city, Tripura. Data were collected using a self-administered Semi-structured Questionnaire for Children/Students and a Social Adjustment Inventory which were custom-made for the study based on measures in the extant research adapted for the Indian context. Findings revealed that students experienced physical (21.9%), psychological (20.9%), and sexual (18.1%) violence at home, and 29.7% of the children had witnessed family violence. Boys were more often victims of physical and psychological violence while girls were more often victims of sexual violence. The social adjustment scores of school children who experienced violence, regardless of the nature of the violence, was significantly lower when compared with scores of those who had not experienced violence (p<0.001). Social adjustment was poorer for girls than boys (p<0.001). The study speaks in favour of early detection and intervention for all child maltreatment subtypes and for children exposed to interparental violence, and highlights the crucial role of schools and school psychology in addressing the problem.

Visual sea-floor mapping from low overlap imagery using bi-objective bundle adjustment and constrained motion

In most visual mapping applications suited to Autonomous Underwater Vehicles (AUVs), stereo visual odometry (VO) is rarely utilised as a pose estimator as imagery is typically of very low framerate due to energy conservation and data storage requirements. This adversely affects the robustness of a vision-based pose estimator and its ability to generate a smooth trajectory. This paper presents a novel VO pipeline for low-overlap imagery from an AUV that utilises constrained motion and integrates magnetometer data in a bi-objective bundle adjustment stage to achieve low-drift pose estimates over large trajectories. We analyse the performance of a standard stereo VO algorithm and compare the results to the modified vo algorithm. Results are demonstrated in a virtual environment in addition to low-overlap imagery gathered from an AUV. The modified VO algorithm shows significantly improved pose accuracy and performance over trajectories of more than 300m. In addition, dense 3D meshes generated from the visual odometry pipeline are presented as a qualitative output of the solution.

Posttraumatic growth and posttraumatic depreciation as predictors of psychological adjustment

Informed by current trauma literature, this study explored the relationships between Posttraumatic Growth (PTG; Tedeschi & Calhoun, 1995), Posttraumatic Depreciation (PTD; Cann et al., 2010) and other post-trauma outcomes including well-being, psychological flourishing, and psychological distress. The predictive utility of PTG and PTD was also examined. The sample comprised 104 trauma survivors who completed the Posttraumatic Growth Inventory – 42 (Baker et al., 2008) and several outcome measures. As expected, PTD showed strong linear correlations with well-being, flourishing and distress, and emerged as a significant predictor of scores on such measures. However, PTG showed negligible correlations with well-being, flourishing and distress. This reaffirms that PTG and PTD measure conceptually distinct and independent dimensions of experience, which has implications for therapeutic practice.

The relationship between self-esteem and psychological adjustment in young adolescents

The study adopts a multi-dimensional construct of self-esteem to examine the relationship between self-perception and psychological adjustment in order to identify specific dimensions that discriminate between disturbed and non-disturbed groups. The disturbed group (n = 33) is derived from a clinical sample and are matched with a non-disturbed group (n = 33) of adolescents. Results indicate that dimensional self-concept scores are significantly lower for clinical subjects while there are no significant differences between groups on the mathematics, honesty, and physical ability dimensions. These findings provide a more fine grained understanding of the relationship between self-esteem and psychological adjustment and emphasize the need to examine self-esteem in terms of its particular dimensions.

Social adjustment and symptomatology in two types of homeless adolescents : runaways and throwaways

Previous research on homeless adolescents has largely ignored the distinction between those who have left home on their volition (runaways) and those who have been forced to leave (throwaways). Fifty-two homeless adolescents in Brisbane, Australia, were assessed to compare male and female runaways and throwaways for social adjustment and symptomatology. Differences for social adjustment (antisocial tendencies and aggression) and symptomatology (social isolation and depression) were predicted. Results indicated that male runaways were significantly more hostile than male throwaways (p < 0,001), and significantly more socially isolated than female runaways (p < 0,025). Female throwaways, however, were significantly more hostile than male throwaways (p < 0,025) and female runaways (p < 0,025). Yet homeless males overall had a significantly stronger urge to act out hostility than homeless females (p < 0,025). In addition, female throwaways were significantly more antisocial than male throwaways (p < 0,001). There were no significant differences for depression. A theory of inner social control (Hirschi, 1969), postulating absence of bonding in earlier socialization, was supported.

The consequences of not taking reasonable steps to obtain finance

In Hauff v Miller [2013] QCA 48 the Queensland Court of Appeal considered an issue that has not previously arisen at appellate level. The case concerned the interaction of the well-known subject to finance clause and other standard contractual provisions...

A framework of Dynamic Difficulty Adjustment in competitive multiplayer video games

The balance between player competence and the challenge presented by a task has been acknowledged as a major factor in providing optimal experience in video games. While Dynamic Difficulty Adjustment (DDA) presents methods for adjusting difficulty in real-time during singleplayer games, little research has explored its application in competitive multiplayer games where challenge is dictated by the competence of human opponents. By conducting a formal review of 180 existing competitive multiplayer games, it was found that a large number of modern games are utilizing DDA techniques to balance challenge between human opponents. From this data, we propose a preliminary framework for classifying Multiplayer Dynamic Difficulty Adjustment (mDDA) instances.

Distribution tap changer adjustment to improve small-scale embedded generator penetration and mitigate voltage rise

This paper addresses the voltage rise constraints that are initiated from increased renewable generation resources in low voltage distribution networks. In this paper, an approach which is able to mitigate these voltage rise constraints and allow for increased distributed generator penetration is presented. The proposed approach involves utilizing the distribution transformers static tap changer to reduce the distribution feeder voltage setpoint. The proposed approach is modeled on a generic low voltage distribution network using the PSS SINCAL© simulation software package and is also implemented in a real low voltage distribution network to verify its practicality. Results indicate that this approach can be implemented to mitigate the voltage rise constraint and increase small-scale embedded generator penetration in a high proportion of low voltage feeders while avoiding any substantial network costs.

Resection-intersection bundle adjustment revisited

Bundle adjustment is one of the essential components of the computer vision toolbox. This paper revisits the resection-intersection approach, which has previously been shown to have inferior convergence properties. Modifications are proposed that greatly improve the performance of this method, resulting in a fast and accurate approach. Firstly, a linear triangulation step is added to the intersection stage, yielding higher accuracy and improved convergence rate. Secondly, the effect of parameter updates is tracked in order to reduce wasteful computation; only variables coupled to significantly changing variables are updated. This leads to significant improvements in computation time, at the cost of a small, controllable increase in error. Loop closures are handled effectively without the need for additional network modelling. The proposed approach is shown experimentally to yield comparable accuracy to a full sparse bundle adjustment (20% error increase) while computation time scales much better with the number of variables. Experiments on a progressive reconstruction system show the proposed method to be more efficient by a factor of 65 to 177, and 4.5 times more accurate (increasing over time) than a localised sparse bundle adjustment approach.

When leadership meets organizational change : the influence of the top management team and supervisory leaders on change appraisals, change attitudes, and adjustment to change

Despite the importance of adaption and change for firm survival, the failure rate of organizational change efforts remains alarmingly high (Beer and Nohria, 2000; Kotter, 1995). In a recent global survey of over 3,000 executives,Meaney and Pung (2008) reported that two-thirds of executives indicated that their firm had failed to successfully implement organizational changes. Similarly, academic researchers have also concluded that difficulties in implementing and managing organizational change efforts often precipitate organizational crises (Probst and Raisch, 2005). As a result, attention has been directed to identify the factors that improve the likelihood of successfully implementing organizational change efforts. While there has been practitioner-oriented discussion around the pivotal role of workplace leaders in reducing resistance to change, only a limited number of empirical studies have examined relationships between leader behavior and employee change attitudes (e.g., Bommer, Rich, and Rubin, 2005; Herold, Caldwell, and Liu, 2008; Nemanich and Keller, 2007; Oreg and Berson, 2011). However...

The effect of multiplayer dynamic difficulty adjustment on the player experience of video games

Multiplayer Dynamic Difficulty Adjustment (mDDA) is a method of reducing the difference in player performance and subsequent challenge in competitive multiplayer video games. As a balance of between player skill and challenge experienced is necessary for optimal player experience, this experimental study investigates the effects of mDDA and awareness of its presence on player performance and experience using subjective and biometric measures. Early analysis indicates that mDDA normalizes performance and challenge as expected, but awareness of its presence can reduce its effectiveness.

Motor Accident Insurance Act 1994 - reasonable excuse for delay in giving notice under s37

The decisions in Perdis v The Nominal Defendant [2003] QCA 555, Miller v the Nominal Defendant [2003] QCA 558 and Piper v the Nominal Defendant [2003] QCA 557 were handed down contemporaneously by the Queensland Court of Appeal on December 15 2003. They consider important issues as to the construction of key provisions of the Motor Accident Insurance Act 1994 (Qld)

Compensation for logdment of caveat without reasonable cause

This article examines s130 of the Land Title Act 1994 (Qld) in detail, and includes an analysis of authorities which have interpreted comparable provisions in other Australian jurisdictions and in New Zealand. Its purpose is to provide a comprehensive guide as to the circumstances in which the court may now be expected to award compensation in respect of the lodgment or continuance of a caveat in Queensland. Finally, the author considers whether the changes which have been embodied in s130 may now be regarded as providing adequate protection for persons who suffer damage as a result of the lodgment or continuance of a caveat which cannot ultimately be sustained.