446 research outputs found
A Multi-Agent Mah Jong Playing System: Towards Real-Time Recognition of Graphic Units in Graphic Representations
In architectural design, sketching is an important means to explore the first conceptual developments in the design process. It is necessary to understand the conventions of depiction and encoding in sketches and drawings if we want to support the architect in the sketching activity. The theory of graphic units provides a comprehensive list of conventions of depiction and encoding that are widely used among architects. These graphic units form useful building blocks to understand design drawings. We investigate whether it is possible to build a system that can recognize graphic units. The technology we are looking at is multi-agent systems. It was chosen for the following reasons: agents can specialize in graphic units, a multi-agent system can deal with ambiguity through negotiation and conflict resolution, and multi-agent systems function in dynamically changing environments. Currently there is no general approach or technology available for multi-agent systems. Therefore, in our research we first set out to make such a multi-agent system. In order to keep the complexity low, we first aim to make a system that can do something simple: playing Mah Jong solitary. The Mah Jong solitary system shares the following important features with a multi-agent system that can recognize graphic units: (1) specialized agents for moves; (2) negotiation between agents to establish the best move; (3) a dynamically changing environment; and (4) search activity for more advanced strategies. The paper presents the theoretical basis of graphic units and multi-agents systems, followed by a description of the multi-agent framework and its implementation. A number of systems that can play Mah Jong at various degrees of competence and accordingly degrees of complexity of multi-agent system, are distinguished. Finally, the paper demonstrates how the findings are informative for a system that can recognize graphic units
Design and testing of pistons and cups for large hydrostatic pumps and motors
A new transmission is being designed for a next generation of large, offshore wind turbines, based on floating cup pumps and motors. The machines have a fixed displacement of around five liter per revolution. The objective of this study is to design, manufacture and test the pistons and cups of these machines. To this end, a new test bench has been designed and build, to measure the leakage and friction of the pistons up to a pressure level of 350 bar. Several sets of pistons and cups have been tested against a reference set which was proven to have very little friction at rated and peak operating conditions. The leakage between the pistons and cups was measured at different piston positions at stationary conditions. The friction between the piston and the cup has been measured continuously. From the tests it can be concluded that the friction force is below 0,01% of the piston force. The leakage losses are less than 0,5% of the total effective flow output
Borealis sound an interactive wall for situational awareness: The impact of responsive architecture on users
This paper refers to the presence of visual communication elements in public spaces using interactive multimedia surfaces. The state of the art, the development of a proposal, and its evaluation are presented. The interactive surface applies to school of music âEscola de MĂșsica do ConservatĂłrio Nacional,â to which a design project was done in an academic context. The proposal aims to explore the incorporation of digital multimedia surfaces enhancing new dynamics while users walk in the interior of the building. Visual content will be displayed, and the interaction between users and the multimedia surfaces is done by the sounds produce by people and instruments. To assess the intuitive nature and relevance of the proposal, satisfaction and usability tests were conducted with the potential users. It was concluded that users appreciated the proposal and was able to perceive the effect peopleâs presence have in the interaction with the multimedia surface.info:eu-repo/semantics/acceptedVersio
Protocol for a single-centre randomised controlled trial of multimodal periarticular anaesthetic infiltration versus single-agent femoral nerve blockade as analgesia for total knee arthroplasty: Perioperative Analgesia for Knee Arthroplasty (PAKA)
Introduction: Total knee arthroplasty (TKA) surgery causes postoperative pain. The use of perioperative injections around the knee containing local anaesthetic, opiates and non-steroidal anti-inflammatory drugs has increased in popularity to manage pain. Theoretical advantages include reduced requirements for analgesia and earlier mobilisation. We propose a single-centre randomised controlled trial of multimodal periarticular anaesthetic infiltration versus femoral nerve anaesthetic blockade as analgesia for TKA. The aim is to determine, in patients undergoing TKA, if there is a difference in patient-reported pain scores on the visual analogue scale (VAS) prior to physiotherapy on day 1 postoperatively between treatment groups.
Methods and analysis: Patients undergoing a primary unilateral TKA at University Hospitals Coventry and Warwickshire Hospitals will be assessed for eligibility. A total of 264 patients will provide 90% power to detect a difference of 12â
mm on the VAS on day 1 postoperatively at the 5% level. The trial will use 1:1 randomisation, stratified by mode of anaesthetic. Primary outcome measure will be the VAS for pain prior to physiotherapy on day 1. Secondary outcome measures include VAS on day 2, total use of opiate analgesia up to 48â
h, ordinal pain scores up to 40â
min after surgery, independent functional knee physiotherapist assessment on days 1 and 2. Oxford knee Scores (OKS), EuroQol (EQ-5D) and Douleur Neuropathic Pain Scores (DN2) will be recorded at baseline, 6â
weeks and 12â
months. Adverse events will be recorded up to 12â
months. Analysis will investigate differences in VAS on day 1 between the two treatment groups on an intention-to-treat basis. Tests will be two-sided and considered to provide evidence for a significant difference if p values are less than 0.05.
Ethics and dissemination: NRES Committee West Midlands, 23 September 2013 (ref: 13/WM/0316). The results will be disseminated via peer-reviewed publications and conference presentations.
Trial registration numbers: ISRCTN 60611146 and EUDRACT Number 2013-002439-10 (protocol code number PAKA-33601-AS117013); Pre-results
A pragmatic randomised controlled trial comparing the efficacy of a femoral nerve block and periarticular infiltration for early pain relief following total knee arthroplasty
Aims
The aim of this study was to compare the effectiveness of a femoral nerve block and a periarticular infiltration in the management of early post-operative pain after total knee arthroplasty (TKA).
Patents and methods
A pragmatic, single centre, two arm parallel group, patient blinded, randomised controlled trial was undertaken. All patients due for TKA were eligible. Exclusion criteria included contraindications to the medications involved in the study and patients with a neurological abnormality of the lower limb. Patients received either a femoral nerve block with 75 mg of 0.25% levobupivacaine hydrochloride around the nerve, or periarticular infiltration with 150 mg of 0.25% levobupivacaine hydrochloride, 10 mg morphine sulphate, 30 mg ketorolac trometamol and 0.25 mg of adrenaline all diluted with 0.9% saline to make a volume of 150 ml.
Results
A total of 264 patients were recruited and data from 230 (88%) were available for the primary analysis. Intention-to-treat analysis of the primary outcome measure of a visual analogue score for pain on the first post-operative day, prior to physiotherapy, was similar in both groups. The mean difference was -0.7 (95% confidence interval (CI) -5.9 to 4.5; p = 0.834). The periarticular group used less morphine in the first post-operative day compared with the femoral nerve block group (74%, 95% CI 55 to 99). The femoral nerve block group reported 39 adverse events, of which 27 were serious, in 31 patients and the periarticular group reported 51 adverse events, of which 38 were serious, in 42 patients up to six weeks post-operatively. None of the adverse events were directly attributed to either of the interventions under investigation.
Conclusion
Periarticular infiltration is a viable and safe alternative to femoral nerve block for the early post-operative relief of pain following TKA. Cite this article: Bone Joint J 2017;99-B:904-11
Effect of Parameters on Oxychlorination of Tert-Butyl Ethers
The effect of concentration, molar ratios of reagents, pH, and temperature on formation of chloro-organic products in reaction of tert-butyl ethers with chloride ions and hydrogen peroxide has been determined. A significant effect of Clâ ions and H2O2 molar ratios on the rate of chloro-organic product formation has been observed. Studies on oxychlorination of tert-butylethyl ether (ETBE) at pH 7, 3.5, and 2.5 have been carried out. It was found that introduction of hydronium ions into the reaction system considerably hastened the process of chloro-organic product formation. Hydronium ions contribute to the formation of the reactive tert-butyl carbocation, which undergoes secondary reactions in the presence of reactive forms of chlorine and oxygen. Moreover, the effect of temperature on ETBE (tert-butylethyl ether) and MTBE (tert-butylmethyl ether) conversions was verified. The reactions of MTBE and ETBE oxychlorination were carried out at temperatures of 5°C, 20°C, and 35°C
Barriers and Facilitators to the Implementation of the Early-Onset Sepsis Calculator:A Multicenter Survey Study
Prior studies demonstrated the neonatal early-onset sepsis (EOS) calculatorâs potential in drastically reducing antibiotic prescriptions, and its international adoption is increasing rapidly. To optimize the EOS calculatorâs impact, successful implementation is crucial. This study aimed to identify key barriers and facilitators to inform an implementation strategy. A multicenter cross-sectional survey was carried out among physicians, residents, nurses and clinical obstetricians of thirteen Dutch hospitals. Survey development was prepared through a literature search and stakeholder interviews. Data collection and analysis were based on the Consolidated Framework for Implementation Research (CFIR). A total of 465 stakeholders completed the survey. The main barriers concerned the expectance of the departmentâs capacity problems and the issues with maternal information transfer between departments. Facilitators concerned multiple relative advantages of the EOS calculator, including stakeholder education, EOS calculator integration in the electronic health record and existing positive expectations about the safety and effectivity of the calculator. Based on these findings, tailored implementation interventions can be developed, such as identifying early adopters and champions, conducting educational meetings tailored to the target group, creating ready-to-use educational materials, integrating the EOS calculator into electronic health records, creating a culture of collective responsibility among departments and collecting data to evaluate implementation success and innovation results.</p
Validity of the Polar V800 heart rate monitor to measure RR intervals at rest
Purpose To assess the validity of RR intervals and short-term heart rate variability (HRV) data obtained from the Polar V800 heart rate monitor, in comparison to an electrocardiograph (ECG). Method Twenty participants completed an active orthostatic test using the V800 and ECG. An improved method for the identification and correction of RR intervals was employed prior to HRV analysis. Agreement of the data was assessed using intra-class correlation coefficients (ICC), BlandâAltman limits of agreement (LoA), and effect size (ES). Results A small number of errors were detected between ECG and Polar RR signal, with a combined error rate of 0.086 %. The RR intervals from ECG to V800 were significantly different, but with small ES for both supine corrected and standing corrected data (ES 0.999 for both supine and standing corrected intervals. When analysed with the same HRV software no significant differences were observed in any HRV parameters, for either supine or standing; the data displayed small bias and tight LoA, strong ICC (>0.99) and small ES (â€0.029). Conclusions The V800 improves over previous Polar models, with narrower LoA, stronger ICC and smaller ES for both the RR intervals and HRV parameters. The findings support the validity of the Polar V800 and its ability to produce RR interval recordings consistent with an ECG. In addition, HRV parameters derived from these recordings are also highly comparable
Selective abdominal venous congestion induces adverse renal and hepatic morphological and functional alterations despite a preserved cardiac function
Venous congestion is an important contributor to worsening renal function in heart failure and the cardiorenal syndrome. In patients, it is difficult to study the effects of isolated venous congestion on organ function. In this study, the consequences of isolated abdominal venous congestion on morphology and function of the kidneys, liver and heart were studied in a rat model. Twelve shamoperated (SHAM) male Sprague Dawley rats were compared to eleven inferior vena cava-constricted (IVCc) rats for twenty-one weeks. Abdominal venous pressure was significantly higher in the IVCc versus SHAM group (p < 0.0001). Indices of liver and kidney weight, function and morphology, inflammation as well as collagen deposition were significantly increased in the IVCc compared to SHAM group, (p < 0.05). Echocardiographic and hemodynamic parameters were largely unaffected by abdominal venous congestion. In this rat model of isolated abdominal venous congestion, retrogradely conducted glomerular hypertension without a concomitant change in glomerular filtration rate was observed. Adverse short-term hepatic morphological alterations were developed which explain the observed organ function dysfunction. Importantly, cardiac function remained comparable between both groups. This study provides relevant insight in the pathophysiology of abdominal congestion on organ function
Mental Rotation Meets the Motion Aftereffect: The Role of hV5/MT+ in Visual Mental Imagery
- âŠ