5,744 research outputs found
Event-Triggered Observers and Observer-Based Controllers for a Class of Nonlinear Systems
In this paper, we investigate the stabilization of a nonlinear plant subject
to network constraints, under the assumption of partial knowledge of the plant
state. The event triggered paradigm is used for the observation and the control
of the system. Necessary conditions, making use of the ISS property, are given
to guarantee the existence of a triggering mechanism, leading to asymptotic
convergence of the observer and system states. The proposed triggering
mechanism is illustrated in the stabilization of a robot with a flexible link
robot.Comment: Proceedings of the 2015 American Control Conference - ACC 201
The Feeling of Color: A Haptic Feedback Device for the Visually Disabled
Tapson J, Gurari N, Diaz J, et al. The Feeling of Color: A Haptic Feedback Device for the Visually Disabled. Presented at the Biomedical Circuits and Systems Conference (BIOCAS), Baltimore, MD.We describe a sensory augmentation system designed to provide the visually disabled with a sense of color. Our system consists of a glove with short-range optical color sensors mounted on its fingertips, and a torso-worn belt on which tactors (haptic feedback actuators) are mounted. Each fingertip sensor detects the observed objectpsilas color. This information is encoded to the tactor through vibrations in respective locations and varying modulations. Early results suggest that detection of primary colors is possible with near 100% accuracy and moderate latency, with a minimum amount of training
Treatment of streptococcal endocarditis with a single daily dose of ceftriaxone sodium for 4 weeks. Efficacy and outpatient treatment feasibility
OBJECTIVE--To evaluate the efficacy and safety of ceftriaxone sodium in the treatment of streptococcal endocarditis. DESIGN--An open, multicenter, noncomparative study with a follow-up of patients for 4 months to 5 years. SETTING--Internal medicine wards and outpatient clinics of hospitals of various sizes in three European countries. PATIENTS--Fifty-nine patients with defined criteria for streptococcal endocarditis. INTERVENTION--Ceftriaxone sodium administered at a once-daily dose of 2 g for 4 weeks. MAIN OUTCOME MEASURES--Clinical outcome and microbiological cure rate. RESULTS--Among the 59 patients, 55 completed the treatment and were followed up for 4 months to 5 years. No patients showed evidence of relapse. Treatment was completely uneventful in 42 patients (71%). A cardiac valve was replaced in four patients (7%) receiving antimicrobial therapy and in six patients (10%) who had completed antimicrobial therapy. One of the 10 valves taken for culture at surgery was positive, but only for microorganisms that were different from the microorganism isolated before the treatment. The treatment had to be interrupted in four patients because of drug allergy. Other side effects were mild except for two cases of reversible neutropenia. The treatment was easy to administer: 27 patients (46%) had no permanent intravenous catheter at any time, seven patients (12%) had such a catheter for less than 4 days. Twenty-three patients (39%) were discharged from the hospital less than 2 weeks after admission. CONCLUSIONS.--Ceftriaxone sodium administered at a once-daily dose of 2 g appears to be an effective and safe treatment of streptococcal endocarditis. In hospitals, this agent may be more convenient to administer than penicillin G with or without aminoglycosides. Some patients may even be treated as outpatients
Effect of physical aging on the low-frequency vibrational density of states of a glassy polymer
The effects of the physical aging on the vibrational density of states (VDOS)
of a polymeric glass is studied. The VDOS of a poly(methyl methacrylate) glass
at low-energy (<15 meV), was determined from inelastic neutron scattering at
low-temperature for two different physical thermodynamical states. One sample
was annealed during a long time at temperature lower than Tg, and another was
quenched from a temperature higher than Tg. It was found that the VDOS around
the boson peak, relatively to the one at higher energy, decreases with the
annealing at lower temperature than Tg, i.e., with the physical aging.Comment: To be published in Europhys. Let
Enhancing transparency of the research process to increase accuracy of findings: A guide for relationship researchers
The purpose of this paper is to extend to the field of relationship science, recent discussions and suggested changes in open research practises. We demonstrate different ways that greater transparency of the research process in our field will accelerate scientific progress by increasing accuracy of reported research findings. Importantly, we make concrete recommendations for how relationship researchers can transition to greater disclosure of research practices in a manner that is sensitive to the unique design features of methodologies employed by relationship scientists. We discuss how to implement these recommendations for four different research designs regularly used in relationship research and practical limitations regarding implementing our recommendations and provide potential solutions to these problems
Enantioselective Catalysis Coupled with Stereodivergent Cyclization Strategies Enables Rapid Syntheses of (+)-Limaspermidine and (+)-Kopsihainanine A
Enantioselective Pd-catalyzed allylic alkylations of dihydropyrido[1,2-a]indolone (DHPI) substrates were used to construct the C20-quaternary stereocenters of multiple monoterpene indole alkaloids. Stereodivergent Pictet–Spengler and Bischler–Napieralski cyclization/reduction cascades furnish the cis- and trans-fused azadecalin subunits present in Aspidosperma and Kopsia alkaloids, respectively, en route to highly efficient syntheses of (+)-limaspermidine and (+)-kopsihainanine A
Commentary : Reproducibility in Psychological Science: When Do Psychological Phenomena Exist?
Peer reviewe
Heat Transport in a Strongly Overdoped Cuprate: Fermi Liquid and Pure d-wave BCS Superconductor
The transport of heat and charge in the overdoped cuprate superconductor
Tl_2Ba_2CuO_(6+delta) was measured down to low temperature. In the normal
state, obtained by applying a magnetic field greater than the upper critical
field, the Wiedemann-Franz law is verified to hold perfectly. In the
superconducting state, a large residual linear term is observed in the thermal
conductivity, in quantitative agreement with BCS theory for a d-wave
superconductor. This is compelling evidence that the electrons in overdoped
cuprates form a Fermi liquid, with no indication of spin-charge separation.Comment: 4 pages, 2 figures, published version, title changed, Phys. Rev.
Lett. 89, 147003 (2002
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