2,632 research outputs found
Fuzzy Integral Based Multi-Sensor Fusion for Arc Detection in the Pantograph-Catenary System
The pantograph-catenary subsystem is a fundamental component of a railway train since it provides the traction electrical power. A bad operating condition or, even worse, a failure can disrupt the railway traffic creating economic damages and, in some cases, serious accidents. Therefore, the correct operation of such subsystems should be ensured in order to have an economically efficient, reliable and safe transportation system. In this study, a new arc detection method was proposed and is based on features from the current and voltage signals collected by the pantograph. A tool named mathematical morphology is applied to voltage and current signals to emphasize the effect of the arc, before applying the fast Fourier transform to obtain the power spectrum. Afterwards, three support vector machine-based classifiers are trained separately to detect the arcs, and a fuzzy integral technique is used to synthesize the results obtained by the individual classifiers, therefore implementing a classifier fusion technique. The experimental results show that the proposed approach is effective for the detection of arcs, and the fusion of classifier has a higher detection accuracy than any individual classifier
Optimal motion control and vibration suppression of flexible systems with inaccessible outputs
This work addresses the optimal control problem
of dynamical systems with inaccessible outputs. A case in which
dynamical system outputs cannot be measured or inaccessible.
This contradicts with the nature of the optimal controllers which can be considered without any loss of generality as state feedback control laws for systems with linear dynamics. Therefore, this work attempts to estimate dynamical system states through a novel state observer that does not require injecting the dynamical system outputs onto the observer structure during its design. A linear quadratic optimal control law is then realized based on the
estimated states which allows controlling motion along with active vibration suppression of this class of dynamical systems with inaccessible outputs. Validity of the proposed control framework is evaluated experimentally
Estimation of nasal cavity and conchae volumes by stereological method
Background: Studies evaluating the mean volumes of nasal cavity and concha
are very rare. Since there is little date on the mentioned topic, we aimed to
carry out the presented study to obtain a volumetric index showing the relation
between the nasal cavity and concha.
Material and methods: The volumes of the nasal cavity and concha were
measured in 30 males and 30 females (18–40 years old) on computed tomography
images using stereological methods.
Results: The mean volumes of nasal cavity, concha nasalis media, and concha
nasalis inferior were 5.95 ± 0.10 cm3, 0.56 ± 0.22 cm3, and 1.45 ± 0.68 cm3;
7.01 ± 0.18 cm3, 0.67 ± 0.31 cm3 and 1.59 ± 0.98 cm3 in females and males,
respectively. There were statistically significant differences in the volume of the
nasal cavity and concha nasalis media (p < 0.05) between males and females,
except for concha nasalis inferior (p > 0.05).
Conclusions: Our results could provide volumetric indexes for the nasal cavity
and concha, which could help the physician to manage surgical procedures
related to the nasal cavity and concha
Ekspresija E-selektina u mišjem sjemeniku nakon njegove pokusne torzije (ishemije/reperfuzije).
Germ cell-specific apoptosis occurs after ischemia/reperfusion of the testis and is dependent on E-selectin expression. The aim of the study was to determine differences in E-selectin expression in testes tissues of control, sham and treatment groups after ischemia/reperfusion in mice. Mice were subjected to 720° testicular torsion for 1 h or 2 h duration (ischemia) followed by detorsion (reperfusion). After 2 h of reperfusion, the testes were fixed in Bouin fixative and immunohistochemical analysis performed for E-Selectin expression. E-selectin expression increased in the ischemic testis and contralateral testis after 2 h of reperfusion in mice. This increase in E-selectin expression may confirm that E-selectins play a key role in mediating of apoptosis in germ cells after ischemia/reperfusion. Thus, the blockage of E-selectins might be a strategy for rescue of post-ischemic testes.Apoptoza germinativnih stanica javlja se nakon ishemije i reperfuzije sjemenika, a ovisna je o ekspresiji E-selektina. Cilj ovog istraživanja bio je odrediti razlike u ekspresiji E-selektina u tkivu sjemenika kontrolne, placebo i pokusne skupine nakon ishemije/reperfuzije u miševa. Miševi su bili podvrgnuti torziji sjemenika od 7200 tijekom jednog ili dva sata (ishemija), nakon čega je slijedila detorzija (reperfuzija). Nakon dva sata reperfuzije tkivo sjemenika bilo je fiksirano u Bouinovom fiksativu i pretraženo imunohistokemijski na ekspresiju E-selektina. Ekspresija E-selektina povećala se u ishemičnih sjemenika nakon dva sata reperfuzije. Može se reći da povećanje ekspresije E-selektina potvrđuje njhovu ključnu ulogu u nastanku apoptoze germinativnih stanica nakon ishemije/reperfuzije pa bi blokada E-selektina mogla biti od važnosti za spašavanje sjemenika nakon ishemije
A soft kinetic data structure for lesion border detection
Motivation: The medical imaging and image processing techniques, ranging from microscopic to macroscopic, has become one of the main components of diagnostic procedures to assist dermatologists in their medical decision-making processes. Computer-aided segmentation and border detection on dermoscopic images is one of the core components of diagnostic procedures and therapeutic interventions for skin cancer. Automated assessment tools for dermoscopic images have become an important research field mainly because of inter- and intra-observer variations in human interpretations. In this study, a novel approach—graph spanner—for automatic border detection in dermoscopic images is proposed. In this approach, a proximity graph representation of dermoscopic images in order to detect regions and borders in skin lesion is presented
A framework for a responsible circular economy
The move towards a Circular Economy (CE) from the perspective of a ‘just transition’ necessitates an approach which deems stakeholder knowledge and agency as central. Under this paradigm the transition to a CE is conceived not as a technocratic challenge, but as a process of socioeconomic transformation grounded in principles of social and environmental justice. We suggest that Responsible Research and Innovation (RRI), as an approach for considering the relation of science to wider society, in particular the constituent concepts of anticipation, inclusion, reflection, and responsiveness (Owen et al., 2013), presents itself as a lens through which we can embed considerations of justice within CE practices. In exploring these dimensions with a critical view to how the CE discourse has often failed to consider who will benefit from the transition to a CE, we present a framework for supporting the design of responsible CE practices. We argue that such a framework can provide a starting point for future refinement and enrichment of the decision context faced by the relevant groups in the course of the transition to a just CE
Content-Based Image Retrieval of Skin Lesions by Evolutionary Feature Synthesis
Abstract. This paper gives an example of evolved features that improve image retrieval performance. A content-based image retrieval system for skin lesion images is presented. The aim is to support decision making by retrieving and displaying relevant past cases visually similar to the one under examination. Skin lesions of five common classes, including two non-melanoma cancer types, are used. Colour and texture features are extracted from lesions. Evolutionary algorithms are used to create composite features that optimise a similarity matching function. Experiments on our database of 533 images are performed and results are compared to those obtained using simple features. The use of the evolved composite features improves the precision by about 7%.
Potential Cost-Effectiveness of RSV Vaccination of Infants and Pregnant Women in Turkey:An Illustration Based on Bursa Data
BackgroundWorldwide, respiratory syncytial virus (RSV) is considered to be the most important viral cause of respiratory morbidity and mortality among infants and young children. Although no active vaccine is available on the market yet, there are several active vaccine development programs in various stages. To assess whether one of these vaccines might be a future asset for national immunization programs, modeling the costs and benefits of various vaccination strategies is needed. Objectives To evaluate the potential cost-effectiveness of RSV vaccination of infants and/or pregnant women in Turkey.MethodsA multi-cohort static Markov model with cycles of one month was used to compare the cost-effectiveness of vaccinated cohorts versus non-vaccinated cohorts. The 2014 Turkish birth cohort was divided by twelve to construct twelve monthly birth cohorts of equal size (111,459 new-borns). Model input was based on clinical data from a multicenter prospective study from Bursa, Turkey, combined with figures from the (inter) national literature and publicly available data from the Turkish Statistical Institute (TUIK). Incremental cost-effectiveness ratios (ICERs) were expressed in Turkish Lira (TL) per quality-adjusted life year (QALY) gained.ResultsVaccinating infants at 2 and 4 months of age would prevent 145,802 GP visits, 8,201 hospitalizations and 48 deaths during the first year of life, corresponding to a total gain of 1650 QALYs. The discounted ICER was estimated at 51,969 TL (26,220 US in 2013) per QALY. Vaccinating only during pregnancy would result in fewer cases prevented than infant vaccination and a less favorable ICER.ConclusionRSV vaccination of infants and/or pregnant women has the potential to be cost-effective in Turkey. Although using relatively conservative assumptions, all evaluated strategies remained slightly below the threshold of 3 times the GDP per capita.</p
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