A biomechanical model for encoding joint dynamics: applications to transfemoral prosthesis control

2012 ◽  
Vol 112 (9) ◽  
pp. 1600-1611 ◽  
Author(s):  
Chris A. McGibbon

This paper presents and tests a framework for encoding joint dynamics into energy states using kinematic and kinetic knee joint sensor data and demonstrates how to use this information to predict the future energy state (torque and velocity requirements) of the joint without a priori knowledge of the activity sequence. The intended application is for enhancing micro-controlled prosthetics by making use of the embedded sensory potential of artificial limbs and classical mechanical principles of a prosthetic joint to report instantaneous energy state and most probable next energy state. When applied to the knee during preferred and fast speed walking in 8 human subjects (66 preferred-speed trials and 50 fast-speed trials), it was found that joint energy states could be consistently sequenced (75% consensus) according to mechanical energy transference conditions and subsequences appeared to reflect the stability and energy dissipation requirements of the knee during gait. When simple constraints were applied to the energy transfer input conditions (their signs), simulations indicated that it was possible to predict the future energy state with an accuracy of >80% when 2% cycle in advance (∼20 ms) of the switch and >60% for 4% (∼40 ms) in advance. This study justifies future research to explore whether this encoding algorithm can be used to identify submodes of other human activity that are relevant to TFP control, such as chair and stair activities and their transitions from walking, as well as unexpected perturbations.

Crisis ◽  
2017 ◽  
Vol 38 (3) ◽  
pp. 202-206 ◽  
Author(s):  
Karl Andriessen ◽  
Dolores Angela Castelli Dransart ◽  
Julie Cerel ◽  
Myfanwy Maple

Abstract. Background: Suicide can have a lasting impact on the social life as well as the physical and mental health of the bereaved. Targeted research is needed to better understand the nature of suicide bereavement and the effectiveness of support. Aims: To take stock of ongoing studies, and to inquire about future research priorities regarding suicide bereavement and postvention. Method: In March 2015, an online survey was widely disseminated in the suicidology community. Results: The questionnaire was accessed 77 times, and 22 records were included in the analysis. The respondents provided valuable information regarding current research projects and recommendations for the future. Limitations: Bearing in mind the modest number of replies, all from respondents in Westernized countries, it is not known how representative the findings are. Conclusion: The survey generated three strategies for future postvention research: increase intercultural collaboration, increase theory-driven research, and build bonds between research and practice. Future surveys should include experiences with obtaining research grants and ethical approval for postvention studies.


2019 ◽  
Vol 24 (4) ◽  
pp. 312-321 ◽  
Author(s):  
Diana Moreira ◽  
Fernando Barbosa

Abstract. Delay discounting (DD) is the process of devaluing results that happen in the future. With this review, we intend to identify specificities in the processes of DD in impulsive behavior. Studies were retrieved from multiple literature databases, through rigorous criteria (we included systematic reviews and empirical studies with adult human subjects), following the procedures of the Cochrane Collaboration initiative. Of the 174 documents obtained, 19 were considered eligible for inclusion and were retained for in-depth analysis. In addition, 13 studies from the manual search were included. Thus, a total of 32 studies were selected for review. The objectives/hypotheses, results, and the main conclusion(s) were extracted from each study. Results show that people with pronounced traits of impulsivity discount rewards more markedly, that is, they prefer immediate rewards, though of less value, or postponed losses, even though they worsen in the future. Taken together, the existing data suggest the importance of inserting DD as a tool for initial assessment in conjunction with measures of addiction and stress level, as well as the consideration of new therapies.


2012 ◽  
pp. 78-90
Author(s):  
Thang Nguyen Ngoc

Knowledge and the capability to create and utilize knowledge today are consid- ered to be the most important sources of a firm’s sustainable competitive advantage. This paper aims to advance understanding of the knowledge creation of firm in Vietnam by studying Alphanam Company. The case illustrates how knowledge- based management pursues a vision for the future based on ideals that consider the relationships of people in society. The finding shows that the case succeeded because of their flexibility and mobility to keep meeting to the changing needs of the customers or stakeholders. The paper also provided some suggestions for future research to examine knowledge-based management of the companies in a different industry segments and companies originating in other countries


2012 ◽  
Vol 487 ◽  
pp. 805-809
Author(s):  
Jun Ma ◽  
Dong Hua Guo

this thesis discusses the main testing technologies at home and abroad relating to the glass bead refractive index, analyses the research emphases relating to the glass bead refractive index testing technology at present and point out the future research trend.


2021 ◽  
Vol 11 (6) ◽  
pp. 2640
Author(s):  
Tomer Fine ◽  
Guy Zaidner ◽  
Amir Shapiro

The involvement of Robots and automated machines in different industries has increased drastically in recent years. Part of this revolution is accomplishing tasks previously performed by humans with advanced robots, which would replace the entire human workforce in the future. In some industries the workers are required to complete different operations in hazardous or difficult environments. Operations like these could be replaced with the use of tele-operated systems that have the capability of grasping objects in their surroundings, thus abandoning the need for the physical presence of the human operator at the area while still allowing control. In this research our goal is to create an assisting system that would improve the grasping of a human operator using a tele-operated robotic gripper and arm, while advising the operator but not forcing a solution. For a given set of objects we computed the optimal grasp to be achieved by the gripper, based on two grasp quality measures of our choosing (namely power grasp and precision grasp). We then tested the performance of different human subjects who tried to grasp the different objects with the tele-operated system, while comparing their success to unassisted and assisted grasping. Our goal is to create an assisting algorithm that would compute optimal grasps and might be integrated into a complete, state-of-the-art tele-operated system.


2021 ◽  
pp. 152483802098554
Author(s):  
Stephanie Gusler ◽  
Jessy Guler ◽  
Rachel Petrie ◽  
Heather Marshall ◽  
Daryl Cooley ◽  
...  

Although evidence suggests that individuals’ appraisals (i.e., subjective interpretations) of adverse or traumatic life events may serve as a mechanism accounting for differences in adversity exposure and psychological adjustment, understanding this mechanism is contingent on our ability to reliably and consistently measure appraisals. However, measures have varied widely between studies, making conclusions about how best to measure appraisal a challenge for the field. To address this issue, the present study reviewed 88 articles from three research databases, assessing adults’ appraisals of adversity. To be included in the scoping review, articles had to meet the following criteria: (1) published no earlier than 1999, (2) available in English, (3) published as a primary source manuscript, and (4) included a measure assessing for adults’ (over the age of 18) subjective primary and/or secondary interpretations of adversity. Each article was thoroughly reviewed and coded based on the following information: study demographics, appraisal measurement tool(s), category of appraisal, appraisal dimensions (e.g., self-blame, impact, and threat), and the tool’s reliability and validity. Further, information was coded according to the type of adversity appraised, the time in which the appraised event occurred, and which outcomes were assessed in relation to appraisal. Results highlight the importance of continued examination of adversity appraisals and reveal which appraisal tools, categories, and dimensions are most commonly assessed for. These results provide guidance to researchers in how to examine adversity appraisals and what gaps among the measurement of adversity appraisal which need to be addressed in the future research.


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