An Efficient Calculation of the Load and Coefficient of Restitution of Impact Between Two Elastic Bodies With a Liquid Lubricant

1996 ◽  
Vol 63 (2) ◽  
pp. 347-352 ◽  
Author(s):  
L. Chang
Keyword(s):  
Impact Load ◽  
Coefficient Of Restitution ◽  
Future Research ◽  
Reasonable Accuracy ◽  
Problem Domain ◽  
Liquid Lubricant ◽  
Elastic Bodies ◽  
Efficient Calculation ◽  
Wide Range ◽  
The Impact

This paper complements several previous papers on modeling of the impact between two elastic bodies with a liquid lubricant. The main feature of the work is the efficient incorporation of various engineering aspects of the impact process making use of approximations consistent with the physical insights of the problem. The model can very efficiently calculate the impact load and the coefficient of restitution with reasonable accuracy for a wide range of the problem domain. The modeling concepts and methodology may be useful in future research on interdisciplinary analyses of the dynamics of mechanical systems in which the interactions are strong between vibrations of the components and impacts in the lubricated kinematic pairs.

The Effects of Technology Supports on Community Grocery Shopping Skills for Students With Intellectual and Developmental Disabilities: A Meta-Analysis

2021 ◽  
pp. 016264342198997
Author(s):  
Sojung Jung ◽  
Ciara Ousley ◽  
David McNaughton ◽  
Pamela Wolfe
Keyword(s):  
Developmental Disabilities ◽  
Positive Impact ◽  
Single Case ◽  
Effect Sizes ◽  
Future Research ◽  
Intellectual And Developmental Disabilities ◽  
Positive Effects ◽  
Analytic Review ◽  
Wide Range ◽  
The Impact

In this meta-analytic review, we investigated the effects of technology supports on the acquisition of shopping skills for students with intellectual and developmental disabilities (IDD) between the ages of 5 and 24. Nineteen single-case experimental research studies, presented in 15 research articles, met the current study’s inclusion criteria and the What Works Clearinghouse (WWC) standards. An analysis of potential moderators was conducted, and we calculated effect sizes using Tau-U to examine the impact of age, diagnosis, and type of technology on the reported outcomes for the 56 participants. The results from the included studies provide evidence that a wide range of technology interventions had a positive impact on shopping performance. These positive effects were seen for individuals across a wide range of ages and disability types, and for a wide variety of shopping skills. The strongest effect sizes were observed for technologies that provided visual supports rather than just auditory support. We provide an interpretation of the findings, implications of the results, and recommended areas for future research.

scholarly journals The effect of water immersion on vection in virtual reality

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Géraldine Fauville ◽  
Anna C. M. Queiroz ◽  
Erika S. Woolsey ◽  
Jonathan W. Kelly ◽  
Jeremy N. Bailenson
Keyword(s):  
Virtual Reality ◽  
Motion Sickness ◽  
Water Immersion ◽  
Sensory Information ◽  
Future Research ◽  
Visually Induced Motion Sickness ◽  
Wide Range ◽  
Induced Motion ◽  
Ground Condition ◽  
The Impact

AbstractResearch about vection (illusory self-motion) has investigated a wide range of sensory cues and employed various methods and equipment, including use of virtual reality (VR). However, there is currently no research in the field of vection on the impact of floating in water while experiencing VR. Aquatic immersion presents a new and interesting method to potentially enhance vection by reducing conflicting sensory information that is usually experienced when standing or sitting on a stable surface. This study compares vection, visually induced motion sickness, and presence among participants experiencing VR while standing on the ground or floating in water. Results show that vection was significantly enhanced for the participants in the Water condition, whose judgments of self-displacement were larger than those of participants in the Ground condition. No differences in visually induced motion sickness or presence were found between conditions. We discuss the implication of this new type of VR experience for the fields of VR and vection while also discussing future research questions that emerge from our findings.

Impacts of International Baccalaureate programmes on teaching and learning: A review of the literature

2018 ◽  
Vol 17 (3) ◽  
pp. 240-261 ◽  
Author(s):  
Anisah Dickson ◽  
Laura B. Perry ◽  
Susan Ledger
Keyword(s):  
Teaching And Learning ◽  
International Baccalaureate ◽  
Thinking Skills ◽  
Critical Thinking Skills ◽  
Pedagogical Practices ◽  
Additional Stress ◽  
Future Research ◽  
Wide Range ◽  
Teachers And Students ◽  
The Impact

International Baccalaureate (IB) programmes are growing rapidly worldwide, driven in part by their global reputation and concept-driven, inquiry-based approach to teaching and learning. This thematic review of a range of literature sources examines the impact of IB programmes on teaching and learning, highlighting trends, challenges, and benefits. Findings of the review revealed that most of the studies, both qualitative and quantitative, examined stakeholders’ perspectives or self-reported experiences of IB programmes; a very small number used research designs that control for confounding factors or allow causal inferences to be drawn. A wide range of stakeholders report that IB programmes develop research and critical thinking skills, intercultural appreciation and global awareness, as well as cultivate collaborative working cultures and creative pedagogical practices among teachers. Challenges include extra demands on teachers for lesson planning and assessment, additional stress for teachers and students, and competing demands and expectations with national requirements. Recommendations are provided which may guide future research endeavours.

scholarly journals Arts-Based Interventions for Professionals in Caring Roles During and After Crisis: A Systematic Review of the Literature

2020 ◽  
Vol 11 ◽  
Author(s):  
Dominik Havsteen-Franklin ◽  
Megan Tjasink ◽  
Jacqueline Winter Kottler ◽  
Claire Grant ◽  
Veena Kumari
Keyword(s):  
Systematic Review ◽  
Future Research ◽  
Safe Place ◽  
Practice Elements ◽  
Qualitative Approaches ◽  
The Arts ◽  
Crisis Events ◽  
Wide Range ◽  
The Impact

Crisis events, such as the COVID-19 pandemic, can have a devastating effect on communities and the care professionals within them. Over recent years, arts-based interventions have helped in a wide range of crisis situations, being recommended to support the workforce during and after complex crisis but there has been no systematic review of the role of arts-based crisis interventions and whether there are cogent themes regarding practice elements and outcomes. We, therefore, conducted a systematic review to (i) define the arts-based change process used during and after crisis events, and (ii) explore the perceptions of intermediate and long-term mental health benefits of arts-based interventions for professionals in caring roles. Our search yielded six studies (all qualitative). All data were thematically aggregated and meta-synthesized, revealing seven practice elements (a safe place, focusing on strengths and protective factors, developing psychosocial competencies to support peers, emotional expression and processing, identifying and naming the impact of the crisis, using an integrative creative approach, and cultural and organizational sensitivity) applied across all six studies, as well as a range of intermediate and long-term benefits shared common features (adapting, growing, and recovering; using the community as a healing resource; reducing or preventing symptoms of stress or trauma reactions, psychophysiological homeostasis). The ways in which these studies were designed independently from one another and yet used the same practice elements in their crisis interventions indicates that there is comparability about how and why the arts-based practice elements are being used and to what effect. Our findings provide a sound basis and meaningful parameters for future research incorporating quantitative and qualitative approaches to firmly establish the effectiveness of art-based interventions, and how arts can support cultural sensitivity, acceptability and indicated outcomes, particularly those relating to stress and trauma during or following a crisis.

scholarly journals Optimal damping coefficient for a class of continuous contact models

2020 ◽  
Vol 50 (2) ◽  
pp. 169-188
Author(s):  
Mohammad Poursina ◽  
Parviz E. Nikravesh
Keyword(s):  
Contact Force ◽  
Analytical Formula ◽  
Coefficient Of Restitution ◽  
Damping Coefficient ◽  
Optimization Strategy ◽  
Continuous Contact ◽  
Optimal Damping ◽  
Wide Range ◽  
Contact Models ◽  
The Impact

Abstract In this study, we develop an analytical formula to approximate the damping coefficient as a function of the coefficient of restitution for a class of continuous contact models. The contact force is generated by a logical point-to-point force element consisting of a linear damper connected in parallel to a spring with Hertz force–penetration characteristic, while the exponent of deformation of the Hertz spring can vary between one and two. In this nonlinear model, it is assumed that the bodies start to separate when the contact force becomes zero. After separation, either the restitution continues or a permanent penetration is achieved. Therefore, this model is capable of addressing a wide range of impact problems. Herein, we apply an optimization strategy on the solution of the equations governing the dynamics of the penetration, ensuring that the desired restitution is reproduced at the time of separation. Furthermore, based on the results of the optimization process along with analytical investigations, the resulting optimal damping coefficient is analytically expressed at the time of impact in terms of system properties such as the effective mass, penetration velocity just before the impact, coefficient of restitution, and the characteristics of the Hertz spring model.

scholarly journals Transparency you can trust: Transparency requirements for artificial intelligence between legal norms and contextual concerns

2019 ◽  
Vol 6 (1) ◽  
pp. 205395171986054 ◽  
Author(s):  
Heike Felzmann ◽  
Eduard Fosch Villaronga ◽  
Christoph Lutz ◽  
Aurelia Tamò-Larrieux
Keyword(s):  
Artificial Intelligence ◽  
Data Protection ◽  
Contextual Factors ◽  
Information Provision ◽  
Human Robot Interaction ◽  
Future Research ◽  
General Data Protection Regulation ◽  
Wide Range ◽  
General Data ◽  
The Impact

Transparency is now a fundamental principle for data processing under the General Data Protection Regulation. We explore what this requirement entails for artificial intelligence and automated decision-making systems. We address the topic of transparency in artificial intelligence by integrating legal, social, and ethical aspects. We first investigate the ratio legis of the transparency requirement in the General Data Protection Regulation and its ethical underpinnings, showing its focus on the provision of information and explanation. We then discuss the pitfalls with respect to this requirement by focusing on the significance of contextual and performative factors in the implementation of transparency. We show that human–computer interaction and human-robot interaction literature do not provide clear results with respect to the benefits of transparency for users of artificial intelligence technologies due to the impact of a wide range of contextual factors, including performative aspects. We conclude by integrating the information- and explanation-based approach to transparency with the critical contextual approach, proposing that transparency as required by the General Data Protection Regulation in itself may be insufficient to achieve the positive goals associated with transparency. Instead, we propose to understand transparency relationally, where information provision is conceptualized as communication between technology providers and users, and where assessments of trustworthiness based on contextual factors mediate the value of transparency communications. This relational concept of transparency points to future research directions for the study of transparency in artificial intelligence systems and should be taken into account in policymaking.

League Tables for Performance Improvement in Health Care

1998 ◽  
Vol 3 (1) ◽  
pp. 50-57 ◽  
Author(s):  
Sandra Nutley ◽  
Peter C. Smith
Keyword(s):  
Health Care ◽  
Health Care Providers ◽  
Analytical Techniques ◽  
Performance Data ◽  
Future Research ◽  
League Table ◽  
Care Providers ◽  
League Tables ◽  
Wide Range ◽  
The Impact

Objectives: Increasingly health care performance data are being disseminated in the form of ‘league tables' of health care providers, with the implication that such publication helps purchasers select the better providers, and spurs providers into improvements. This paper examines progress to date. Methods: Three stages of the league table process are considered: measurement, analysis and action. Results: A wide range of measurement schemes are now in place, although the emphasis has been on process variables and mortality as a measure of outcome. Several analytical techniques have been deployed to help users make sense of league tables, and to help determine the causes of variations in reported performance. The weakest aspect of current methods relates to the use to which such analysis is put. Conclusions: A haphazard approach to using league table data exists, with few reports on the impact of publication. A variety of directions for future research into the use of performance data are needed.

Comparison of rural versus urban residence for symptoms and quality of life in recurrent ovarian cancer: Baseline analysis of GOG-0259, an NRG Oncology/GOG study.

2017 ◽  
Vol 35 (15_suppl) ◽  
pp. e18083-e18083 ◽  
Author(s):  
Sarah M. Belcher ◽  
Susan M. Sereika ◽  
Zan M. Dodson ◽  
Meghan K. Mattos ◽  
Teresa Hagan ◽  
...  
Keyword(s):  
Quality Of Life ◽  
Ovarian Cancer ◽  
Marital Status ◽  
Recurrent Ovarian Cancer ◽  
Future Research ◽  
Protective Effects ◽  
Financial Barriers ◽  
Wide Range ◽  
The Impact

e18083 Background: Women with recurrent ovarian cancer (OC) experience a wide range of cancer- and treatment-related symptoms that negatively impact quality of life (QOL). Studies have reported healthcare disparities by geographic residence related to distance, time, and financial barriers to accessing high quality care. However, no studies have evaluated the impact of residence on symptoms and QOL in women with OC. Therefore, our objectives were to evaluate whether geographic residence (urban versus rural) is associated with symptoms and QOL in a sample of women with recurrent OC. Methods: The Center for Health Equity Research and Promotion conceptual framework guided analyses of baseline GOG-0259 data. We mapped zip codes to RUCA commuter codes and compared sociodemographic and clinical variables between rural and urban groups using two-sample t and chi-square tests. We used MANCOVA, adjusted for age and marital status, to test for associations between residence and symptoms (Symptom Representation Questionnaire) and QOL (Functional Assessment of Cancer Therapy-Ovarian). Results: Rural (n = 122, 25%) and urban (n = 374, 75%) women were similar in all sociodemographic and clinical comparisons except for marital status (83% vs. 70% married, p = .003). Women reported moderate symptom severity (M = 5.5, SD = 2.3) and QOL scores similar to other OC studies (M = 108.4, SD = 19.5). In multi-variate analyses, age and marital status were both associated with symptoms; marital status was associated with QOL. Geographical residence was not associated with either symptoms or QOL. Conclusions: Counter to previous research, there were no symptom or QOL disparities based on geographic residence in this sample. Possible explanations to be explored in future research include a) cooperative group selection bias for women with good access to care regardless of geographic residence and b) protective effects of marital status on symptoms and QOL.

Not All Transformational Leadership Behaviors Are Equal: The Impact of Followers’ Identification With Leader and Modernity on Taking Charge

2016 ◽  
Vol 24 (3) ◽  
pp. 318-334 ◽  
Author(s):  
Jie Li ◽  
Stacie Furst-Holloway ◽  
Larry Gales ◽  
Suzanne S. Masterson ◽  
Brian D. Blume
Keyword(s):  
Transformational Leadership ◽  
Indirect Effects ◽  
High Performance ◽  
Relative Effect ◽  
Future Research ◽  
Intellectual Stimulation ◽  
Performance Expectations ◽  
Wide Range ◽  
Taking Charge ◽  
The Impact

This study investigates how each dimension of transformational leadership directly and indirectly influences followers’ change-oriented behaviors. Using a sample of 329 independent leader–follower dyads from a wide range of Chinese organizations, we examine followers’ identification with leader as an intervening variable between the four dimensions of transformational leadership (“core” transformational behaviors, high-performance expectations, individualized support, and intellectual stimulation) and followers’ taking charge behaviors. Results showed that intellectual stimulation had the highest relative effect size that was largely due to its direct effect on taking charge. Individualized support only exerted a significant indirect effect. Additionally, the negative direct and positive indirect effects of high-performance expectations rendered its total effect nonsignificant. Furthermore, the direct, indirect, and total effects of “core” transformational behaviors were nonsignificant. We also found that followers’ value of modernity moderated the effect of identification with leader on taking charge. The indirect effects of intellectual stimulation, individualized support, and high-performance expectations were significant when modernity was high but nonsignificant when it was low. Implications for theory, practice, and future research are discussed.

scholarly journals Staphylococcus aureus Arsenal To Conquer the Lower Respiratory Tract

mSphere ◽  
2021 ◽  
Vol 6 (3) ◽  
Author(s):  
Mariane Pivard ◽  
Karen Moreau ◽  
François Vandenesch
Keyword(s):  
Staphylococcus Aureus ◽  
Respiratory Tract ◽  
Virulence Factors ◽  
Lower Respiratory Tract ◽  
Defense Mechanisms ◽  
Future Research ◽  
Epithelial Barrier ◽  
Content Type ◽  
Wide Range ◽  
The Impact

ABSTRACT Staphylococcus aureus is both a commensal and a pathogenic bacterium for humans. Its ability to induce severe infections is based on a wide range of virulence factors. S. aureus community-acquired pneumonia (SA-CAP) is rare and severe, and the contribution of certain virulence factors in this disease has been recognized over the past 2 decades. First, the factors involved in metabolism adaptation are crucial for S. aureus survival in the lower respiratory tract, and toxins and enzymes are required for it to cross the pulmonary epithelial barrier. S. aureus subsequently faces host defense mechanisms, including the epithelial barrier, but most importantly the immune system. Here, again, S. aureus uses myriad virulence factors to successfully escape from the host’s defenses and takes advantage of them. The impact of S. aureus virulence, combined with the collateral damage caused by an overwhelming immune response, leads to severe tissue damage and adverse clinical outcomes. In this review, we summarize step by step all of the S. aureus factors implicated in CAP and described to date, and we provide an outlook for future research.

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