18 research outputs found

    Simulation of Single and Twin Impinging Jets in Cross-flow of VTOL Aircrafts (Review)

    Get PDF
    When operating near the ground beneath a Vertical/Short Take-Off and Landing (VSTOL) aircraft a complex turbulent 3D flow is generated. This flow field can be represented by the configuration of twin impinging jets in a cross-flow. Studying these jets is a significant parameter for the design of VTOL aircraft. This flowfield during very low speed or hover flight operations is very complex and time dependent. An important number of experimental researches and simulations have been carried out to be able to understand much better these flows related with powered lift vehicles. Computational Fluid Dynamics (CFD) approach will be used in this paper work for simulation purposes of a single and twin impinging jet through and without crossflow

    Hybrid Model for the Analysis of Human Gait: A Non-linear Approach

    Get PDF
    In this work, a generalization of the study of the human gait was made from already existent models in the literature, like models of Keller and Kockshenev. In this hybrid model, a strategy of metabolic energy minimization is combined in a race process, with a non-linear description of the movement of the mass center’s libration, trying to reproduce the behavior of the walk-run transition. The results of the experimental data, for different speed regimes, indicate that the perimeter of the trajectory of the mass center is a relevant quantity in the quantification of this dynamic. An experimental procedure was put into practice in collaboration with the research group in Biomedical Engineering, Basic Sciences and Laboratories of the Manuela Beltrán University in Bogotá, Colombia

    State estimation of a dehydration process by interval analysis

    Get PDF
    This article presents a general methodology of state estimation by interval analysis in a dynamic system modeled by difference equations. The methodology is applied to a pineapple osmotic dehydration process, in order to predict the behavior of the process within a range of allowed perturbation. The paper presents simulations and validations

    Learning HCI Across Institutions, Disciplines and Countries: A Field Study of Cognitive Styles in Analytical and Creative Tasks

    Get PDF
    Human-computer interaction (HCI) is increasingly becoming a subject taught in universities around the world. However, little is known of the interactions of the HCI curriculum with students in different types of institutions and disciplines internationally. In order to explore these interactions, we studied the performance of HCI students in design, technology and business faculties in universities in UK, India, Namibia, Mexico and China who participated in a common set of design and evaluation tasks. We obtained participants’ cognitive style profiles based on Allinson and Hayes scale in order to gain further insights into their learning styles and explore any relation between these and performance. We found participants’ cognitive style preferences to be predominantly in the adaptive range, i.e. with combined analytical and intuitive traits, compared to normative data for software engineering, psychology and design professionals. We further identified significant relations between students’ cognitive styles and performance in analytical and creative tasks of a HCI professional individual. We discuss the findings in the context of the distinct backgrounds of the students and universities that participated in this study and the value of research that explores and promotes diversity in HCI education

    Collaborative learning as educational strategy for deaf children: A systematic literature review

    No full text
    © 2017 Association for Computing Machinery. The education of people with disabilities requires special attention and the use of teaching and learning strategies that can be adapted to every particular disability. This study focuses on the education of deaf children as part of a larger project that aims to mix teaching strategies like Logogenia and Fitzgerald Key with interactive storytelling and collaborative learning to support literacy teaching to these children. Since deaf people learn using the visual channel as main input, we believe that technology could play a key role in the development of such environments where user interfaces should be specifically designed to attract children's attention.∗ We conducted a systematic literature review in order to find what researchers have done to apply Collaborative or Cooperative Learning in the education of deaf children and also what kind of emerging technologies are used to enhance collaborative environments. A total of 229 studies were found in 7 different databases. The results of this study show that Collaborative Learning has been used along with different kinds of technology in the education of deaf people with positive outcomes like improving skills in sign language, literacy and communication.status: publishe

    Method for Evaluating VR-Based Tools for Collaborative Design

    No full text

    Developing an Interactive Tabletop Mediated Activity to Induce Collaboration by Implementing Design Considerations Based on Cooperative Learning Principles

    No full text
    Constructive collaboration can be a difficult matter. For this reason, we are implementing and studying an interactive-tabletop-mediated activity that aims at inducing collaboration among participants. The resulting activity ‘Orbitia’ is designed as a serious game. Participants are asked to act as a space- mining crew, which has to collect minerals with a rover and rely on a camera- drone for reconnaissance, while keeping the rover out of harm and managing limited resources. In this paper we provide an account of how we designed Orbitia’s pedagogical structuring by relying on the Johnsons’ cooperative learning approach whose fundamental concept is “positive interdependence”. More particularly, we show how we worked on resource, role and task inter- dependence to design three collaboration-inducing ‘flagship’ devices: the rover- steering-device (RSD), the item-locating-device (ILD) and the responsibility- activating-device (RAD)

    Male sexual dysfunction and HIV--a clinical perspective.

    No full text
    Sexual dysfunction in men with HIV is often overlooked by clinicians owing to many factors, including the taboo of sexuality. The improved life expectancy of patients with HIV requires physicians to consider their general wellbeing and sexual health with a renewed interest. However, data on sexual dysfunction in those with HIV are scarce. Erectile dysfunction (ED) is the most common sexual dysfunction in men, with a prevalence of ∼30-50% and is frequent even in men <40 years of age. HIV infection itself is the strongest predictor of ED, and many factors related to the infection-fear of virus transmission, changes in body image, HIV-related comorbidities, infection stigma, obligatory condom use-all impair erectile function. The diagnosis and treatment of sexual dysfunction is based on a multidisciplinary approach, which involves specialists in both infectious diseases and sexual medicine. Particular attention should be paid to the promotion of safer sex in these patients. This Review, describes the issues surrounding sexual dysfunction in men with HIV and aims to provide clinical advice for the physician treating these patients
    corecore