Traction-energy balancing adaptive control with slip optimization for wheeled robots on rough terrain

On rough terrain, excessive wheel slippage is easily generated by changes of surface conditions such as soil types and geometries. It induces considerable loss of wheel traction and battery energy. To prevent this, wheeled robots should consistently recognize the current situation generated between wheel and surface. And also wheeled robots are required to optimally control wheel motion in limited wheel traction and battery capacity. Therefore, this paper proposes a novel wheel control algorithm based on slip optimization of traction and energy, which is adaptive to change of surface condition. Proposed wheel control algorithm is called Traction-Energy Balancing Adaptive Control (TEB) in this paper and TEB assigns optimized rotation speed to each wheel by observing wheel slip ratio which is a key parameter of TEB. As functions of TEB, TEB is largely divided into three main parts; (1) slip optimizer (2) slip controller (3) SC-compensator. In the slip optimizer, two optimal slip models were derived as a function of slip ratios regarding maximum traction and tractive efficiency using experimental data about wheel-terrain interaction in three types of soil (grass, gravel and sand). And the optimal slip models were employed in order to determine a desired slip value of wheel with observation of a change in actual robot velocity as control input in the slip controller. For optimal slip control, the proposed slip controller is based on conventional PID controller with compensating disturbance in the controller (SC-compensator) which occurs by change of surface shapes. In the SC-compensator, radial function networks (RBFN) was applied in the slip controller and RBFN was of help to readjust previously set PID gains depending on occurred slip error. Finally, TEB was experimentally verified by controlling a real robot having four wheels on various terrain types.     

Concurrent tobacco use and risky drinking in South Africa: Results from the South African National Health and Nutrition Examination Survey

The aim of this study was to examine socio-demographic and psychosocial correlates of concurrent tobacco use and risky drinking. We analysed data from the cross-sectional South African National Health and Nutrition Examination Survey (SANHANES-1) 2011–2012. The sample included 14 764 adolescents and adults aged 15 years and older. They responded to questions on tobacco and alcohol use, psychosocial, and socio-demographic indicators. Results indicate that 9.6% (16.8% among men and 3.5% among women) of South Africans were involved in concurrent tobacco use and risky drinking, 18.2% in current tobacco use only, and 20.3% in risky drinking only. In covariate adjusted analysis, being 25 to 64 years, being male, belonging to the coloured population group, residing in urban areas, having experienced three or more traumatic events, and poor self-rated health were associated with concurrent tobacco use and risky drinking. Findings suggest socio-demographic and health factors are important for public health interventions in addressing concurrent tobacco and alcohol use in South Africa.     

Support groups for parents with an adult child suffering from bipolar disorder

Confronted with the disconcerting behaviour exhibited by their children, parents of bipolar patients are in severe distress. Research focuses on the study of the ‘burden’ that the pathology puts on caregivers, owing to their experience of depression, sometimes combined with the presence of hostile attitudes and negative affects. In France, parents of adult patients encounter an initial specific difficulty: they are not systematically included in the care management system. Thanks to the initiative of an association of psychiatrists and psychoanalysts, the authors set up a psychoanalytic support group for the parents of ‘bipolar’ adults. The diagnosis of a bipolar disorder is established by a psychiatrist within a medical structure. Support groups for parents do exist in France, but their experiences have not led to scientific publications on this specific topic. Existing publications focus on other types of pathology and other therapeutic approaches. In this article, we will highlight how this type of psychoanalytic support group, with operating rules based on the theoretical work of Anzieu, can help parents of patients with bipolar disorders. Group participants accepted the principle of a research study that maintained their anonymity. We collected and analysed qualitative data from the first year of the group, so we highlight the specific difficulties of these parents, faced with chronic disease. The relevance of our qualitative study also resides in the data collected over a period of time, enabling us to see the progress made, and encouraging us to reflect on the place of psychoanalytic groups for parents, as well as on the care management of this pathology.     

Vulnerability of Individuals With Mental Disorders to Epistemic Injustice in Both Clinical and Social Domains

Many individuals who have mental disorders often report negative experiences of a distinctively epistemic sort, such as not being listened to, not being taken seriously, or not being considered credible because of their psychiatric conditions. In an attempt to articulate and interpret these reports we present Fricker’s concepts of epistemic injustice (Fricker, 2007, p. 1) and then focus on testimonial injustice and hermeneutic injustice as it applies to individuals with mental disorders. The clinical impact of these concepts on quality of care is discussed. Within the clinical domain, we contrast epistemic injustice with epistemic privilege and authority. We then argue that testimonial and hermeneutic injustices also affect individuals with mental disorders not only when communicating with their caregivers but also in the social context as they attempt to reintegrate into the general society and assume responsibilities as productive citizens. Following the trend of the movement of mental health care to the community, the testimonies of people with mental disorders should not be restricted to issues involving their own personal mental states.     

UNDERSTANDING PARENTING STRESS AND CHILDREN'S BEHAVIOR PROBLEMS AMONG HOMELESS,SUBSTANCE‐ABUSING MOTHERS

This article tested a model of parenting stress as a mediator between maternal depressive symptoms, emotion regulation, and child behavior problems using a sample of homeless, substance‐abusing mothers. Participants were 119 homeless mothers (ages 18–24 years) and their young children (ages 0–6 years). Mothers responded to questions about their depressive symptoms, emotion regulation, parenting stress, and child behavior problems. A path analysis showed that maternal depressive symptoms were positively associated with child behavior problems through increased parenting stress whereas maternal cognitive reappraisal was negatively associated with child behavior problems through decreased parenting stress. Moreover, maternal expressive suppression was negatively related to child externalizing problems. Findings support the parenting stress theory and highlight maternal parenting stress as a mechanism associated with homeless children's mental health risk. This study has significant implications for understanding the parenting processes underlying child's resilience in the context of homelessness and maternal substance use.     

Frequency of finger looking during finger counting is related to children's working memory capacities

Finger counting can be useful in solving arithmetic problems, noticeably because it reduces the working memory demand of mental calculations. However, proprioceptive information might not be sufficient to keep track of the number of fingers raised during problem solving, and visual input may play an important role in this process. The present study was designed to address this question and shows that 8-year-old children look at their fingers in 60% of the trials during finger counting when solving additive problems. Moreover, our results reveal that the frequency of finger looking is negatively correlated with working memory capacities and is higher for more difficult problems. These findings suggest that finger looking is recruited in managing the cognitive demand of the arithmetic task, probably by providing additional external cues to monitor the number of steps that have to be incremented during finger counting.     

Heuristics versus direct calculation,and age-related differences in multiplication: an evidence accumulation account of plausibility decisions in arithmetic

We offer a new theoretical angle for cognitive arithmetic, which is that evidence accumulation may play a role in problem plausibility decisions. We build upon previous studies that have considered such a hypothesis, and here formally evaluate the paradigm. We develop the finding that performance differences, due to variations in strategy use and aging effects, can indeed be reasonably explained through these accumulation-to-bound cognitive models. Results suggest that these models may be effectively used to learn more about the underlying cognitive processes. In this study, we modelled young (18–24) and older (68–82) adults’ solution times in performing arithmetic verification (e.g. whether 8?×?5?=?41 is true/false). The domain-relevant factors in strategy use (problem-verification heuristics) and aging differences (older/younger adult groups) were analyzed by a response process model of the latency data, that is fit by participant and item. Lower thresholds accounted for the faster response times (RTs) for problems solved with heuristics (arithmetic rule-violation checking strategies), as opposed to problems solved by calculation approaches. A more rapid accumulation accounted for faster RTs on problems in which two arithmetic rules were violated (strategy combination) rather than one. Third, higher thresholds (i.e. preferring to have greater certainty before responding) accounted for older adults’ slower speed. These findings are in support of accumulation models being relevant for more complex cognitive tasks, as well as to account for the age-related differences therein.     

Protecting Women from the Negative Effects of Body Dissatisfaction: The Role of Differentiation of Self

ABSTRACT

Body dissatisfaction is a prevalent and concerning issue among college age women. Due to its strong association with eating pathology, identification of moderating variables is a crucial line of inquiry. The present study investigated the ability for an intrapersonal differentiation-of-self variable (“I” position) to attenuate the impact of body dissatisfaction on anorexia and bulimia symptoms among college women participants. Study findings indicated that an “I” position moderated the body dissatisfaction-bulimia relationship and the body dissatisfaction-anorexia relationship. These findings signified the protective influence of a high “I” position for women with high levels of body dissatisfaction. Research and therapeutic implications are discussed.