Photo- and Thermo-Induced Changes in Optical Constants and Structure of Thin Films from GeSe2-GeTe-ZnTe System

AbstractWe examined the condition of preparation of thin films from GeSe2-GeTe-ZnTe system by thermal evaporation and changes in their optical properties after exposure to light and thermal annealing. The results for composition analysis of thin films showed absence of Zn independently of the composition of the bulk glass. By X-ray diffraction (XRD) analysis it was found that a reduction of ZnTe in ZnSe in bulk materials takes of place during the film deposition. A residual from ZnSe was observed in the boat after thin film deposition. Optical constants (refractive index, n and absorption coefficient, α) and thickness, d as well as the optical band gap, Eg, depending of the content of Te in ternary Ge-Se-Te system are determined from specrophotometric measurements in the spectral range 400-2500nm applying the Swanepoel's envelope method and Tauc's procedure. With the increase of Te content in the layers the absorption edge is shifted to the longer wavelengths, refractive index increases while the optical band gap decreases from 2.02eV for GeSe2 to 1.26eV for Ge34Se42Te24. The values of the refractive index decrease after annealing of all composition and Eg increase, respectively. Thin films with composition of Ge27Se47Te9Zn17 and Ge28Se49Te10Zn13 were prepared by co-evaporation of (GeSe2)78(GeTe)22 and Zn from a boat and a crucible and their optical properties, surface morphology and structure were investigated. The existence of a correlation between the optical band gap and the copostion of thin films from the system studied was demonstrated

Electromagnetic scattering of two-dimensional electronic systems

No abstract available

Spectral Analysis of Hand Tremors induced during a Fatigue Test

In this paper, we analyze various kinds of hand tremors in the time and frequency domain, that are induced by performing a set of hand actions. We collected the tremor data using a simple, wearable accelerometer from 15 healthy individuals that had varying levels of athleticism. The overall results presented here show that the physiologic tremors in range of 8-14 Hz are most noticeable under fatigue

Features of Physiologic Tremor in Diabetic Patients

In this paper, we estimate the effect of fatigue on physiological tremors in adults suffering from diabetes. We used a simple, wearable accelerometer to collect the acceleration data from 5 diabetic subjects with varying physical activity levels. Fatigue was induced via an intermittent submaximal isometric handgrip protocol, normalized for individual grip strength, until voluntary exhaustion. The overall results presented here show that the physiologic tremors in the range of 10-14 Hz are most noticeable under fatigue

In Situ Remote Monitoring of Novel Biodegradable Cardiovascular Stents - Design and Validation

No abstract available

In Situ Remote Monitoring of Novel Biodegradable Cardiovascular Stents - Design and Validation

No abstract available

Classification of Fatigue Phases in Healthy and Diabetic Adults Using Wearable Sensor

Fatigue is defined as “a loss of force-generating capacity” in a muscle that can intensify tremor. Tremor quantification can facilitate early detection of fatigue onset so that preventative or corrective controls can be taken to minimize work-related injuries and improve the performance of tasks that require high-levels of accuracy. We focused on developing a system that recognizes and classifies voluntary effort and detects phases of fatigue. The experiment was designed to extract and evaluate hand-tremor data during the performance of both rest and effort tasks. The data were collected from the wrist and finger of the participant’s dominant hand. To investigate tremor, time, frequency domain features were extracted from the accelerometer signal for segments of 45 and 90 samples/window. Analysis using advanced signal processing and machine-learning techniques such as decision tree, k-nearest neighbor, support vector machine, and ensemble classifiers were applied to discover models to classify rest and effort tasks and the phases of fatigue. Evaluation of the classifier’s performance was assessed based on various metrics using 5-fold cross-validation. The recognition of rest and effort tasks using an ensemble classifier based on the random subspace and window length of 45 samples was deemed to be the most accurate (96.1%). The highest accuracy (~98%) that distinguished between early and late fatigue phases was achieved using the same classifier and window length

Remote Monitoring of Absorbable Cardiovascular Stents Using Millimetre Waves

In this paper, we propose a corrosion monitoring scheme for the absorbable cardiovascular stents composed of magnesium alloys. We show that the structural integrity of such mesh-type tubular stents can be evaluated using millimetre-scale electromagnetic waves. With the passage of time, the strut thickness of the stent decreases due to corrosion which is subsequently observed in terms of a frequency shift in the simulated scattering response