830 research outputs found
Design of a body energy harvesting system for the upper extremity
Converting energy from human upper limb motions into electrical energy is a challenge, as low frequency movements have to be converted into repetitive movements to effectively drive electromechanical generators. The prototype of an electromagnetic linear generator with gyrating mass is presented. The mechanical motion model first was simulated and the design was evaluated during different activities. An average power output of about 50 ÎĽW was determined with a maximum power output of 2.2 mW that is sufficient to operate sensors for health monitoring
An Omnidirectional Aerial Manipulation Platform for Contact-Based Inspection
This paper presents an omnidirectional aerial manipulation platform for
robust and responsive interaction with unstructured environments, toward the
goal of contact-based inspection. The fully actuated tilt-rotor aerial system
is equipped with a rigidly mounted end-effector, and is able to exert a 6
degree of freedom force and torque, decoupling the system's translational and
rotational dynamics, and enabling precise interaction with the environment
while maintaining stability. An impedance controller with selective apparent
inertia is formulated to permit compliance in certain degrees of freedom while
achieving precise trajectory tracking and disturbance rejection in others.
Experiments demonstrate disturbance rejection, push-and-slide interaction, and
on-board state estimation with depth servoing to interact with local surfaces.
The system is also validated as a tool for contact-based non-destructive
testing of concrete infrastructure.Comment: Accepted submission to Robotics: Science and Systems conference 2019.
9 pages, 12 figure
Cost-optimal adaptive iterative linearized FEM for semilinear elliptic PDEs
We consider scalar semilinear elliptic PDEs where the nonlinearity is
strongly monotone, but only locally Lipschitz continuous. We formulate an
adaptive iterative linearized finite element method (AILFEM) which steers the
local mesh refinement as well as the iterative linearization of the arising
nonlinear discrete equations. To this end, we employ a damped Zarantonello
iteration so that, in each step of the algorithm, only a linear Poisson-type
equation has to be solved. We prove that the proposed AILFEM strategy
guarantees convergence with optimal rates, where rates are understood with
respect to the overall computational complexity (i.e., the computational time).
Moreover, we formulate and test an adaptive algorithm where also the damping
parameter of the Zarantonello iteration is adaptively adjusted. Numerical
experiments underline the theoretical findings
Sexual dysfunction prevalence, risk factors, and help-seeking behavior in opioid agonist treatment and general psychiatry: a cross-sectional study
BackgroundMental disorders pose a high risk for the occurrence of sexual dysfunctions (SD). This study aimed to investigate prevalence of risk factors and help-seeking behavior for sexual dysfunctions in patients with opioid use disorder compared to patients seeking psychotherapeutic help.MethodsNinety-seven patients at two opioid agonist treatment (OAT) centers and 65 psychotherapeutic patients from a psychiatric practice (PP) in Switzerland were included in the study. Self-report assessments comprised sexual functioning (IIEF: International Index of Erectile Function; FSFI: Female Sexual Function Index), depressive state, psychological distress, alcohol consumption, nicotine use, and a self-designed questionnaire on help-seeking behavior. We used chi-squared and Mann–Whitney U tests for group comparisons and binary logistic regression models to identify variables predicting the occurrence of sexual dysfunctions.ResultsThere was no statistically significant difference (p = 0.140) in the prevalence of SD between OAT (n = 64, 66.0%) and PP sample (n = 35, 53.8%). OAT patients scored significantly higher in scales assessing nicotine use (p < 0.001) and depressive state (p = 0.005). Male OAT patients scored significantly worse on the Erectile Function scale (p = 0.005) and female PP patients scored significantly worse on the FSFI Pain domain (p = 0.022). Opioid use disorder, higher age, and being female predicted the occurrence of SD in the total sample. In the OAT sample, only higher age remained predictive for the occurrence of SD. A lack of help-seeking behavior was observed in both groups, with only 31% of OAT patients and 35% of PP patients ever having talked about their sexual health with their treating physician.ConclusionSD are common among psychiatric patients receiving OAT and general psychiatric patients seeking psychotherapy. Professionals providing mental healthcare to patients must emphasize prevention and routine assessments of sexual functioning needs
Four-modulus "Swiss Cheese" chiral models
We study the 'Large Volume Scenario' on explicit, new, compact, four-modulus
Calabi-Yau manifolds. We pay special attention to the chirality problem pointed
out by Blumenhagen, Moster and Plauschinn. Namely, we thoroughly analyze the
possibility of generating neutral, non-perturbative superpotentials from
Euclidean D3-branes in the presence of chirally intersecting D7-branes. We find
that taking proper account of the Freed-Witten anomaly on non-spin cycles and
of the Kaehler cone conditions imposes severe constraints on the models.
Nevertheless, we are able to create setups where the constraints are solved,
and up to three moduli are stabilized.Comment: 40 pages, 10 figures, clarifying comments added, minor mistakes
correcte
Impact of Clinical Presentation on Early Vascular Healing After Bioresorbable Vascular Scaffold Implantation
BackgroundOptimal strut coverage and early vascular healing are important factors to reduce the risk of stent thrombosis. Data on early vascular healing with the new bioresorbable vascular scaffolds (BVS) are lacking. Further, healing response after BVS implantation in different clinical presentation has not been fully investigated. Methods and ResultsWe assessed with optical coherence tomography (OCT) the early vascular response to BVS implantation in 26 consecutive patients presenting with acute coronary syndrome (ACS) or stable angina (SA). Images from 16 BVSs (17,166 struts) in ACS patients and 17 BVSs (23,045 struts) in SA patients were analyzed. The mean implanted BVS diameter and length was 3.10.4mm and 20.4 +/- 5.8mm. At mean 47.6 +/- 6.3 days, overall 99% of BVS struts were covered. There were no differences between ACS and SA on the amount of tissue coverage per strut (0.09 +/- 0.02mm vs. 0.09 +/- 0.01mm;P=0.86, respectively) and lumen area stenosis (24.2 +/- 19.3% vs. 22.3 +/- 22.0%;P=0.78, respectively). However, a numerically higher proportion of protruding (ACS 1.2 +/- 2.7%;SA 4.2 +/- 6.5%;P=0.11) and malapposed (ACS 0.4 +/- 0.5%;SA 2.4 +/- 5.8%;P=0.18) struts were observed in SA compared to ACS, with trendy better healing score in ACS (1.87 +/- 1.67 vs. 5.28 +/- 7.28, P=0.08). ConclusionEarly after BVS implantation almost complete scaffold strut coverage without any thrombi was observed by OCT, independent by the clinical presentation at index coronary intervention. However, BVS in ACS lesions were associated with easier strut penetration and a trendy better healing score compared with SA
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