1,720,967 research outputs found
The multi-parametric weight optimization of a hydraulic actuator
No full textThis research was derived from the experimental observation that hydraulic actuators are positioned on machines that are subjected to movements and whose dynamic actions, the accelerations, are very high; it is acceptable to think of an actuator for an anthropomorphic robot. From this point of view, the weight of the actuator plays a fundamental role in the performance of the machine. In order to face this problem, a real hydraulic cylinder has been designed (for use on an earth moving machine) both analytically (adopting the theories of continuous mechanics) and numerically through finite element analysis. The results obtained were then generalized by determining functions that in relation to specific values of the variables, such as working pressure, allow one to determine the minimum weight of the component and its geometric configuration. The functions also made it possible to identify the most significant contributions to the overall weight of the component and therefore the elements on which to focus the subsequent lightening process. In particular, the greatest contribution is made by obtaining relations that are completely general and therefore adaptable to different case studies
Design Approach of Medical Devices for Regulation Compatibility: A Robotic Rehabilitation Case Study
No full textRegulations and normative framework strongly affect requirements and potential design constraints of devices, especially in critical environments like the medical field, characterized by a complex interaction among design, therapy procedures and user needs. In order to optimize the design process, the awareness of the designer about the compound information net generated by the required documentation becomes therefore fundamental. Depicting a custom mapping of required data and referring documents for the development and commercialization of a medical device as required by the Conformité Européenne (CE) marking process, this paper presents a design approach directly suitable for robotic rehabilitation systems, which aims at easing the regulations compatibility of the designed product. This method is applied to the illustrative case study of the LEPRE (LEg Programmable REhabilitation) robotic system, with particular attention to data collection and analysis for the evaluation of clinical background and demonstration of equivalence required by the device clinical evaluation report, according to MEDical DEVices (MEDDEV) 2.7/1 guidelines. Indications for the modifications required to adapt it to further application fields are also suggested
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Lupus anticoagulant and bilateral optic disc edema: a case report.
No full textWe present the case of a 29-year-old woman with the rare combination of lupus anticoagulant and bilateral optic disc edema. The linked etiopathologic problems are discussed to provide a proper clinical and ophthalmologic definition
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Design Process of Medical Devices for Robotic Rehabilitation: An Open Innovation-Inspired Approach
No full textThe design process of innovative medical devices, and especially robotic systems for rehabilitation purposes, entails the collaboration among different stakeholders. Moreover, regulations strongly affect the products development, e.g. providing unexpected technical requirements and design constraints. In this paper, an innovative open innovation-inspired model for the design process of medical devices is presented. This model aims at optimizing the employed resources (such as time and cost) and allows overcoming the limits of the traditional linear design model, and specifies i) which stakeholders are involved in the different phases of the process, and ii) the role of the regulations. Special emphasis is placed on the contribution of users and operators (as physiotherapists or caregivers), in addition to physicians and engineers. The contribution of the regulatory aspect is analysed both from a general point of view, with international validity, and punctually, referring to MEDDEV 2.7/1 guideline as illustrative case study. Strength points and limits of the proposed model are highlighted, evaluating examples of incremental and disruptive innovation, like the adoption of new materials or the implementation of functional innovations
Dispelling the Myths Behind First-author Citation Counts
Full text linkWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
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