Electrical properties of amorphous Se70Ge30−xMx system, where M represents silver, cadmium or lead

Current-voltage characteristics and DC electrical conductivity were measured for Se₇₀Ge_30−xM_x ( and M=Ag, Cd or Pb) thin film samples as a function of temperature and thickness. DC conductivity increases with temperature and with the addition of Ag, Cd or Pb, while it decreases with increasing film thickness. The observed increase in conductivity with Pb is higher than that with Cd, which in turn is higher than that with Ag. The obtained results showed that the conduction activation energy has two values ΔE_σ1 and ΔE_σ2 indicating the presence of two different conduction mechanisms through the investigated range of temperature (308-453 K). Current-voltage curves of the investigated samples are typical for a memory switch. The mean value of the threshold voltage increases with film thickness and decreases with increasing temperature in the range (308-403 K) and with the addition of Ag, Cd or Pb. The obtained mean value (0.471) of the ratio ε/ΔE_σ2 (where ε is the threshold voltage activation energy) for the investigated compositions agrees with the value of 0.5 obtained theoretically on the basis of an electrothermal model. Moreover, the obtained values of ΔT_breakdown for most of the investigated compositions are in the same order with those obtained before. Therefore the switching phenomenon in the investigated compositions can be explained according to the electrothermal model.     

Risk perceptions and participation in colorectal cancer screening.

Interviewed 124 siblings (mean age 56.4 yrs) of high risk colorectal cancer (CRC) patients and 171 siblings (mean age 58.8 yrs) of average-risk CRC patients to examine the relationship of risk-factor perceptions to perceived susceptibility and participation in a CRC screening test. Results show minimal differences among siblings with respect to perceived susceptibility. Although high-risk siblings were more likely to participate in screening, only 20.2% cited heredity as a risk-increasing factor, and among these siblings, there was no relationship between screening participation and the citation of any specific risk factors, including heredity. Findings suggest that beliefs about risk-increasing factors may be more important determinants of behavior than beliefs about risk-decreasing factors. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Radiation and depolarization of multibeam offset reflectors fed bymultimode pyramidal horns

The depolarization contents of the radiating currents on the surface of a multibeam offset parabola are minimized, for different beams, using multimode pyramidal horn feeds. Small percentages of the TE ₁₁ and TE₂₀ modes are used, respectively, for vertical and horizontal polarizations, in combination with the fundamental TE₁₀ mode. The mixture ratio increases for feeds with higher pointing angles to the reflector surface. Additionally, the beams that are away from the symmetry plane, suffer changes in the polarization bearing angles, which increase for further beams. Far radiated fields are computed from the depolarization minimized reflector currents, using both the orthogonal components of the linear polarization, for a 3M offset reflector with a diameter-to-focal-length ratio of unity, at 4 GHz. Minimized depolarization levels of around -40 dB for vertical polarization, and of around -34 dB for horizontal polarization are found. The linearly and circularly polarized diagonal horn feeds yield symmetric pencil beams. Their polarization, however, is quite high and difficult to control for linear polarization. For circular polarization, to the contrary, the depolarization is quite low     

A simple algorithm for sidelobe cancellation in a partiallyadaptive linear array

It is argues that the far-field lobes of the edge elements of a uniformly excited linear array are nearly equal to the sidelobes of the array itself, and hence the edge elements are ideal for cancellation of specific sidelobes of the pattern. This supports the concept of partial adaptivity using only the edge elements. This technique is suitable for real-time implementation because only the edge elements require direct control; the inner elements are controlled by programmable read-only memories. Other advantages reported are: the nulls produced specifically by control of the edge elements are deep and wide, and the main-beam gain is not much affected by the sidelobe cancellation     

IoMT-Enabled Fusion-Based Model to Predict Posture for Smart Healthcare Systems

Smart healthcare applications depend on data from wearable sensors (WSs) mounted on a patient’s body for frequent monitoring information. Healthcare systems depend on multi-level data for detecting illnesses and consequently delivering correct diagnostic measures. The collection of WS data and integration of that data for diagnostic purposes is a difficult task. This paper proposes an Errorless Data Fusion (EDF) approach to increase posture recognition accuracy. The research is based on a case study in a health organization. With the rise in smart healthcare systems, WS data fusion necessitates careful attention to provide sensitive analysis of the recognized illness. As a result, it is dependent on WS inputs and performs group analysis at a similar rate to improve diagnostic efficiency. Sensor breakdowns, the constant time factor, aggregation, and analysis results all cause errors, resulting in rejected or incorrect suggestions. This paper resolves this problem by using EDF, which is related to patient situational discovery through healthcare surveillance systems. Features of WS data are examined extensively using active and iterative learning to identify errors in specific postures. This technology improves position detection accuracy, analysis duration, and error rate, regardless of user movements. Wearable devices play a critical role in the management and treatment of patients. They can ensure that patients are provided with a unique treatment for their medical needs. This paper discusses the EDF technique for optimizing posture identification accuracy through multi-feature analysis. At first, the patients’ walking patterns are tracked at various time intervals. The characteristics are then evaluated in relation to the stored data using a random forest classifier.     

Analytic Beta-Wavelet Transform-Based Digital Image Watermarking for Secure Transmission

The rapid development in the information technology field has introduced digital watermark technologies as a solution to prevent unauthorized copying and redistribution of data. This article introduces a self-embedded image verification and integrity scheme. The images are firstly split into dedicated segments of the same block sizes. Then, different Analytic Beta-Wavelet (ABW) orthogonal filters are utilized for embedding a self-segment watermark for image segment using a predefined method. ABW orthogonal filter coefficients are estimated to improve image reconstruction under different block sizes. We conduct a comparative study comparing the watermarked images using three kinds of ABW filters for block sizes 64 × 64, 128 × 128, and 256 × 256. We embed the watermark using the ABW-based image watermarking method in the 2-level middle frequency sub-bands of the ABW digital image coefficients. The imperceptibility and robustness of the ABW-based image watermarking method image is evaluated based on the Peak Signal to Noise Ratio (PSNR) and Correlation coefficient values. From the implementation results, we came to know that this ABW-based image watermarking method can withstand many image manipulations compared to other existing methods.     

Effects of Annealing Temperatures on the Structural and Dielectric Properties of ZnO Nanoparticles

ZnO nanoparticles with hexagonal wurtzite structure were synthesized by using microwave irradiation. The effects of annealing temperatures on the structural, surface morphology and dielectric properties of annealed ZnO nanoparticles were investigated by XRD, FTIR spectra, and dielectric measurements. The XRD reveals the presence of hexagonal wurtzite structure of ZnO average grain size 25.7–36.4 nm. The spectra obtained from FTIR containing two intense absorption bands are attributed to bending and stretching vibrations absorption of Zn–O bond for all annealed ZnO nanoparticles. Dielectric properties of annealed ZnO nanoparticles at different temperatures were studied with respect to frequency. The dielectric measurements reveal that the dielectric response of ZnO nanoparticles is significantly enhanced, especially in the low-frequency range. In conclusion, both the rotation direction polarization and space charge polarization due to a large amount of oxygen vacancies and nano-size effects are responsible for the enhancement of the dielectric properties of ZnO nanoparticles.     

Dynamics of gas-phase trichloramine (NCl3) in chlorinated, indoor swimming pool facilities

Trichloramine (NCl(3)) is recognized as an irritant of the human respiratory system and other tissues. Processes that lead to volatilization from the liquid phase allow for human exposure to gas-phase NCl(3) in swimming pool settings. The dynamics of these processes are not well defined. A N,N-diethyl-p-phenylenediamine/potassium iodide (DPD/KI)-based wet-chemistry method for measuring gas-phase NCl(3) concentration was verified and applied in chlorinated, indoor swimming pool facilities. Other gas-phase oxidants in the air of indoor pools provided interference of 15% or less. The DPD/KI method was applied for the measurement of gas-phase NCl(3) in four chlorinated, indoor swimming pool facilities. All results showed a correlation between bather loading and gas-phase NCl(3) concentration. The nature of swimmer activities also influenced air quality, presumably because of the effects of these activities on mixing near the gas-liquid interface. PRACTICAL IMPLICATIONS: The activities of swimmers promote transfer of volatile compounds from water to the surrounding air. For chlorinated, indoor pool facilities, this can lead to exposure to gas-phase chemicals that can cause irritation of the respiratory system and other tissues. The focus of this study was on NCl(3), a common disinfection by-product (DBP) in chlorinated pools. However, the conditions that promote NCl(3) transfer are likely to promote transfer of other volatile chemicals from water to air. As such, it is possible that other DBPs formed in pools may also contribute to diminished air quality.