42 research outputs found
On the Experimental Analysis of Integral Sliding Modes for Yaw Rate and Sideslip Control of an Electric Vehicle with Multiple Motors
With the advent of electric vehicles with multiple motors, the steady-state and transient cornering responses can be designed and implemented through the continuous torque control of the individual wheels, i.e., torque-vectoring or direct yaw moment control. The literature includes several papers on sliding mode control theory for torque-vectoring, but the experimental investigation is so far limited. More importantly, to the knowledge of the authors, the experimental comparison of direct yaw moment control based on sliding modes and typical controllers used for stability control in production vehicles is missing. This paper aims to reduce this gap by presenting and analyzing an integral sliding mode controller for concurrent yaw rate and sideslip control. A new driving mode, the Enhanced Sport mode, is proposed, inducing sustained high values of sideslip angle, which can be limited to a specified threshold. The system is experimentally assessed on a four-wheel-drive electric vehicle. The performance of the integral sliding mode controller is compared with that of a linear quadratic regulator during step steer tests. The results show that the integral sliding mode controller significantly enhances the tracking performance and yaw damping compared to the more conventional linear quadratic regulator based on an augmented singletrack vehicle model formulation. © 2018, The Korean Society of Automotive Engineers and Springer-Verlag GmbH Germany, part of Springer Natur
Reflexivity, the picturing of selves, the forging of methods
This paper addresses alternative models for a reflexive methodology and examines the ways in
which doctoral students have appropriated these texts in their theses. It then considers the
indeterminate qualities of those appropriations. The paper offers a new account of reflexivity as
'picturing', drawing analogies from the interpretation of two very different pictures, by
VelĂĄzquez and Tshibumba. It concludes with a more open and fluid account of reflexivity,
offering the notion of 'signature', and drawing on the work of Gell and also Deleuze and
Guattari in relation to the inherently specific nature of 'concepts' situated in space and time
Effectiveness of probiotics in the prevention of carious lesions during treatment with fixed orthodontic appliances.
Prolonged Grief Disorder and Symptoms of Anxiety and Depression among Bereaved Family Caregivers in the Context of Palliative Home Care
Background: This study aimed to investigate the prevalence and the psychological comorbidity of PGD among bereaved family caregivers of palliative care cancer patients. We also examined the discriminant validity of two simple and reliable tools in correctly categorized individuals with PGD. Methods: A cross-sectional study was conducted with 157 bereaved participants (77.1% females, mean age = 43.50 ± 14.04 years, mean time since the loss = 3.59 years) recruited from three palliative home care services. These participants completed the Prolonged Grief Scale (PG-13) and the Hospital Anxiety and Depression Scale (HADS). Results: The prevalence of PGD within the sample was 4.46% (i.e., = 7/157). Participants scored higher than the cut-off on the PG-13 and the HADS-D. Symptoms of PGD were positively correlated with depression levels. The ROC curve analysis showed that the HADS-D was outstanding in categorizing individuals with prolonged grief disorder from those without PGD. A HADS-D score of â„7.5 was able to categorize participants with a sensitivity of 0.90 and a specificity of 0.73. Conclusions: Overall, these results highlight the relationship between grief and depression symptoms and their exceptional discriminant validity among correctly identified individuals with PGD
Fear of COVID-19 and Future Orientation: Different Profiles in Dealing With the Pandemic and Associations With Loneliness and Posttraumatic Growth
Clinical Impact Statement The use of a person-oriented approach focusing on the existence of patterns among the individuals, rather than mean and correlations characterizing the variable-oriented research could be worthwhile for a more complex picture of the impact of the pandemic. In this vein, this study points out different ways of reacting to the COVID-19 pandemic resulting from the combination of fear and future orientation. Moreover, the perceived loneliness of individuals should be considered by clinicians because it is associated with dysfunctional profiles of reaction. The profile named "Constructively Preoccupied" characterized by both high fear and high future orientation has greater posttraumatic growth.Objective: This study aimed to examine the profiles of reaction to the COVID-19 pandemic based on the combination of fear and future orientation, as well as their sociodemographic, situational, and relational predictors. We also compared posttraumatic growth between the profiles. Method: A sample of 640 Italian participants completed the Multidimensional Assessment of COVID-19-Related Fears (MAC-RF), the Future Orientation Scale (FOS), the UCLA Loneliness Scale-Version 3, and the Posttraumatic Growth Inventory (PTGI). Results: Latent profile analysis indicated a 4-class solution as the best-fitting model. The first profile ("Detached") comprised 9.9% of the sample and was characterized by both low fear and future orientation. The second profile ("Hopeful") concerned 49.9% of the sample and it featured low fear and high future orientation. The third profile ("Constructively Preoccupied") involved 35.5% of the sample and was distinguished by high fear and high future orientation. The fourth profile ("Fearful") included 4.6% of the sample and was marked by high fear and low future orientation. Multinomial logistic regressions indicated that the female gender was more likely to be associated with the Constructively Preoccupied profile, while older age was more likely to be associated with the Hopeful one. Higher perceived loneliness was associated with all profiles except the Hopeful. Results of comparisons showed substantial differences in posttraumatic growth between the profiles. The Constructively Preoccupied profile showed the greatest posttraumatic growth. Conclusions: Overall, these results point out the various profile of reaction to the pandemic and that adopting a person-oriented approach could enhance their grasp
Maladaptive Daydreaming in an Adult Italian Population During the COVID-19 Lockdown
During the COVID-19 outbreak, individuals with or without mental disorders may resort to dysfunctional psychological strategies that could trigger or heighten their emotional distress. The current study aims to explore the links between maladaptive daydreaming (MD, i.e., a compulsive fantasy activity associated with distress and psychological impairment), psychological symptoms of depression, anxiety, and negative stress, and COVID-19-related variables, such as changes in face-to-face and online relationships, during the COVID-19 lockdown in Italy. A total of 6,277 Italian adults completed an online survey, including socio-demographic variables, COVID-19 related information, the 16-item Maladaptive Daydreaming Scale (MDS-16), and Depression, Anxiety, and Stress Scales-21 Items (DASS-21). Based on an empirically derived cut-off score, 1,082 participants (17.2%) were identified as probable maladaptive daydreamers (MDers). A binary logistic regression revealed that compared to controls, probable MDers reported that during the COVID-19 lockdown they experienced higher levels of anxiety and depression, decreased online social relationships, and, surprisingly, stable or increased face-to-face social relationships. Given the peculiar characteristics of the pandemic context, these findings suggest that the exposure to the risk of contagion had probably exacerbated the tendency of probable MDers to lock themselves inside their mental fantasy worlds, which in turn may have contributed to further estrangement from online social relationships and support, thus worsening their emotional distress