1,635 research outputs found

    An alternative control structure for telerobotics

    Get PDF
    A new teletobotic control concept which couples human supervisory commands with computer reasoning is presented. The control system is responsive and accomplishes an operator's commands while providing obstacle avoidance and stable controlled interactions with the environment in the presence of communication time delays. This provides a system which not only assists the operator in accomplishing tasks but modifies inappropriate operator commands which can result in safety hazards and/or equipment damage

    In My View

    Get PDF

    HLA-Associated viral mutations are common in human immunodeficiency virus type 1 elite controllers

    Get PDF
    Elite controllers (EC) of human immunodeficiency virus type 1 (HTV-1) maintain viremia below the limit of detection without antiretroviral treatment. Virus-specific cytotoxic CD8+ T lymphocytes are believed to play a crucial role in viral containment, but the degree of immune imprinting and compensatory mutations in EC is unclear. We obtained plasma gag, pol, and nef sequences from HLA-diverse subjects and found that 30 to 40% of the predefined HLA-associated polymorphic sites show evidence of immune selection pressure in EC., compared to approximately 50% of the sites in chronic progressors. These data indicate ongoing viral replication and escape from cytotoxic T lymphocytes are present even in strictly controlled HTV-1 infection

    Light my elbows: a cycling jacket incorporating electronic yarn

    Get PDF
    There is a need for illuminated cycle clothing that is comfortable and safe when cycling, and stylish to wear during other activities. It is particularly challenging to integrate lighting within textiles without compromising the drape and comfort of the textile structure. A team of electronics, textiles and fashion specialists was formed to design and make an illuminated jacket for use by cyclists. The jacket incorporates bespoke woven panels that integrate electronic yarns within the pattern. These were designed and made for this project, with fluorescent and retroreflective yarns also included in the weave. LEDs integrated within the electronic yarns illuminate the elbows of the jacket, without causing constraint or adding excess volume. The movement of the jacket elbows during cycling widens the body outline and makes the lighting eye-catching. The collaboration between electronics and textiles experts overcame challenges including development of electrical circuitry designed specifically to fit into the jacket unobtrusively, without interfering with movement or rucksack straps. Electrical connections were required between the electronic yarns assimilated within the weave. Standard, rigid solder joints would have been difficult to form without damaging the cloth and would have been liable to breakage within the garment structure, so embroidery techniques were used to create flexible, conductive connections. The illuminated jacket provides a working prototype, demonstrating the potential for further collaborative ventures in which electronics are integrated into garments that are stylish, functional and 'wearable'. Further interdisciplinary research will include the development of additional wearable prototypes that enhance safety and wellbeing, whilst addressing the recycling of the textiles and garments, including the safe separation and disposal of electronic yarn and other components that provide electrical functionality

    Revisiting consistency conditions for quantum states of systems on closed timelike curves: an epistemic perspective

    Full text link
    There has been considerable recent interest in the consequences of closed timelike curves (CTCs) for the dynamics of quantum mechanical systems. A vast majority of research into this area makes use of the dynamical equations developed by Deutsch, which were developed from a consistency condition that assumes that mixed quantum states uniquely describe the physical state of a system. We criticise this choice of consistency condition from an epistemic perspective, i.e., a perspective in which the quantum state represents a state of knowledge about a system. We demonstrate that directly applying Deutsch's condition when mixed states are treated as representing an observer's knowledge of a system can conceal time travel paradoxes from the observer, rather than resolving them. To shed further light on the appropriate dynamics for quantum systems traversing CTCs, we make use of a toy epistemic theory with a strictly classical ontology due to Spekkens and show that, in contrast to the results of Deutsch, many of the traditional paradoxical effects of time travel are present.Comment: 10 pages, 6 figures, comments welcome; v2 added references and clarified some points; v3 published versio

    Fit for purpose? Pattern cutting and seams in wearables development

    Get PDF
    This paper describes how a group of practitioners and researchers are working across disciplines at Nottingham Trent University in the area of Technical Textiles. It introduces strands of ongoing enquiry centred around the development and application of stretch sensors on the body, focusing on how textile and fashion knowledge are being reflexively revealed in the collaborative development of seamful wearable concepts, and on the tensions between design philosophies as revealed by definitions of purpose. We discuss the current research direction of the Aeolia project, which seeks to exploit the literal gaps found in pattern cutting for fitted stretch garments towards experiential forms and potential interactions. Normative goals of fitness for purpose and seamlessness are interrogated and the potential for more integrated design processes, which may at first appear ‘upside down’, is discussed

    A third dimension in the mirror? How senior managers design products and organizations

    Get PDF
    Individual CEO characteristics may affect architectural choices through the application of managerial discretion. Systems such as organizations and their products are not purely driven toward modularity because of external forces. Individual CEO characteristics may constitute an additional dimension to established mirroring considerations that impacts both the choice of architecture and the correspondence between product and organization architectures

    Thirty Years After Michael E. Porter: What Do We Know About Business Exit?

    Get PDF
    Although a business exit is an important corporate change initiative, the buyer’s side seems to be more appealing to management researchers than the seller’s because acquisitions imply growth, i.e., success. Yet from an optimistic viewpoint, business exit can effectively create value for the selling company. In this paper we attempt to bring the relevance of the seller’s side back into our consciousness by asking: What do we know about business exit? We start our exploration with Porter (1976), focusing on literature that investigates the antecedents of, barriers to, and outcomes of business exit. We also include studies from related fields such as finance and economics.1 Through this research we determine three clusters of findings: factors promoting business exit, exit barriers, and exit outcomes. Overall, it is the intention of this paper to highlight the importance of business exit for research and practice. Knowing what we know about business exits and their high financial value we should bear in mind that exit need not mean failure but a new beginning for a corporation

    Use of the Spine AdVerse Events Severity (SAVES) System to Categorize and Report Adverse Events in Spine Surgery.

    Get PDF
    Introduction: Analysis of adverse events (AEs) in spine surgery has historically been retrospective, utilizing hospital administrative data. Our objective was to determine the incidence, severity and effect on hospital length of stay (LOS) for AEs in spine surgery using the Spine AdVerse Events Severity (SAVES V2) system. Methods: AEs for all surgical spine patients at our institution were prospectively collected for 18 months and correlated with retrospective data from operative reports and H&Ps. Statistical analyses compared patient demographics, diagnoses, and surgical characteristics to hospital length of stay and likelihood of adverse events. Results: This system captured 75% (765/977) of surgical cases for all indications over the study period. 73% (541/743) of patients experienced at least one AE, with an average of 1.2 AEs per patient (range 0-5). The most common AEs were pain control (31%), urinary retention (9.7%), wound infection (6.3%), and incidental durotomy (5.8%). For patients experiencing at least one AE, 30% had no effect on LOS, 48% increased LOS by 1-2 days, 15% increased LOS by 3-7 days, and 7% had prolonged LOS greater than 8 days. Our system captured 25.4% more adverse events (60.0% vs. 34.6%) than hospital administrative data. Univariate analysis revealed patient age, emergent surgery, diagnostic and surgical categories, and spine region to be predictors of both AEs and LOS. Instrumentation was predictive of increased LOS but not AEs. The type of AE was strongly associated with LOS. Multivariable analysis of AE likelihood demonstrated emergent surgery to be the strongest independent predictor with an adjusted odds ratio of 8.5 versus elective surgery. Discussion: Spine surgery is associated with a high incidence of adverse events, which often prolong hospital length of stay. Better characterization of adverse events and their predictors could lead to improved management strategies that reduce patient morbidity and mortality
    corecore