Scaling Properties of Ge-SixGe1-x Core-Shell Nanowire Field Effect Transistors

We demonstrate the fabrication of high-performance Ge-SixGe1-x core-shell nanowire field-effect transistors with highly doped source and drain, and systematically investigate their scaling properties. Highly doped source and drain regions are realized by low energy boron implantation, which enables efficient carrier injection with a contact resistance much lower than the nanowire resistance. We extract key device parameters, such as intrinsic channel resistance, carrier mobility, effective channel length, and external contact resistance, as well as benchmark the device switching speed and ON/OFF current ratio.Comment: 5 pages, 4 figures. IEEE Transactions on Electron Devices (in press

Assessment of oral acetazolamide on postoperative pain after laparoscopic cholecystectomy

Background and aim: Carbon dioxide (Co2) is used during laparoscopy for producing pneumoperttoneum. Combination of this gas with irrigation fluid in the abdomen produces carbonic acid which creates two kinds of abdominal and referred pain to right shoulder. In the present research we have studied the effect of oral acetazolamide in reducing postoperative pain after laparoscopic cholecystectomy. Methods: This clinical trial was performed in 88 patients with cholelithiasis without any complication that were candidate for laparoscopic cholecystectomy. The patients devided randomly and equally in two groups. The experimental group received Acetazolamide (250mg orally 24 hours before surgery every 8 hours) and control group received placebo. Abdominal and shoulder pain measured using Mc Gill pain score by a person who was blind for both groups. Pain measurement was performed in four different times before and after the surgery discharge from recovery and 24 hours after surgery. Data were analyzed by using SPSS software. Results: We observed that mean pain scores was significantly higher in acetazolamide group compared to the placebo group 24 hours after the operation (P0.05). Conclusion: Although acetazolamide can reduce abdominal pain referred to right shoulder by reducing acidity in peritoneal irrigation fluid but this drug can increase abdominal pain in the site of surgery with damaged tissues by producing tissue acidosis (as a side effect of drug)

Enhancing mechanical properties of 3D-printed PLAs via optimization process and statistical modeling

This paper investigates the optimization of 3D printing by 1.75 mm filaments of poly-lactic acid (PLA) materials. The samples are printed separately and glued together to join the tensile device for the failure load and checking the surface roughness. The printing method in this research is Fused Deposition Modeling (FDM), in which the parameters of Infill Percentage (IP), Extruder Temperature (ET), and Layer Thickness (LT) are considered variable parameters for the 3D printer, and according to the Design of Experiments (DOE), a total of 20 experiments are designed. The parametric range is considered to be 15–55% for IP, 190–250 °C for ET, and 0.15–0.35 mm for LT. The optimization model is conducted according to the Response Surface Method (RSM), in which the ANOVA and plot tables are examined. Moreover, the samples’ maximum failure load, weight, fabrication time, and surface roughness are considered output responses. Statistical modeling shows that by increasing the IP and setting the ET at 220 °C, the failure load of the samples increases, and the maximum failure load reaches 1218 N. The weight and fabrication time of the specimen are optimized at the same time to achieve maximum failure load with less surface roughness. By comparing the predicted and actual output for the optimum samples, the percentage error for all results is less than 5%. The developed optimization method is revealed to be accurate and reliable for FDM 3D printing of PLAs

Natural frequency of F.G. rectangular plate by shear deformation theory

Natural frequency of functionally graded (F.G.) rectangular plate is carried out by using second-order shear deformation theory (SSDT). The material properties of functionally graded rectangular plates, except the Poisson's ratio, are assumed to vary continuously through the thickness of the plate in accordance with the exponential law distribution. The equations of motion are obtained by energy method. Numerical results for functionally graded plates are given in dimensionless graphical forms and the effects of material properties on natural frequency are determined

Designing Tuneable Narrowband Bandpass Filter Utilizing Neural Network

Abstract: In this study we aim at adjusting the singleband and dualband bandpass filter designed in a ED02AH technology. The quality factor and center frequency of the filter will change by varactor diodes. Here, we use a neural network to acquire the proper biasing voltages of varactor diodes in order to obtain specific gain and quality factor

Structural health monitoring (SHM) for composite structure undergoing tensile and thermal testing

Application of ultrasonic guided waves generated by piezoelectric smart transducers has become one of the widely-used techniques in structural health monitoring. This technique has led to significant improvements and profound effects in the field of aircraft reliability and safety. Lamb wave propagation on composite plate-like structure undergoing mechanical testing is investigated in the paper. Smart PZT actuator/sensor is bonded on the carbon-fiber and glassfiber epoxy composites, which are subjected to tensile and thermal stress tests. The acquired results indicate the changes in scattering waves in composites materials due to the applied thermal and tensile force. Wavelet analysis was incorporated in this research work in order to distinguish different structural status

The effect of corrective exercises on balance in elderly women with hyperkyphosis

Background: Women with hyperkyphosis have impaired balance and increased body sway, which can increase their risk of falls. Impaired balance and poor postural stability are the main risk factors for falling. This study aimed to study the effect of corrective exercises on balance in elderly women with hyperkyphosis. Methods and Materials: In this quasi experimental study, 30 adult women (age range, 60-75 years old) were selected using a purposive sampling and assigned randomly into the experimental and control groups. Participants in the experimental group took part in an 8-week (3 sessions a week) corrective exercise program. In this period, the control group did not receive any corrective exercise program. The flexicurve ruler and Berg balance scale were used in pre- and post-tests to measure kyphosis angle and balance, respectively. This study was conducted in Spring 2014 at Jahandideh Nursing Home in Arak city, Iran. The number of falls and fears of falling was also recorded. To analyze data, dependent t-test and covariate analysis at a significance level of

Steady-State Thermal Analysis of Functionally Graded Rotating Disks Using Finite Element and Analytical Methods

A steady-state thermal analysis for a hollow and axisymmetric functionally graded (FG) rotating disk with a uniform thickness was performed in this study. In the studied FG disk, metal and ceramic materials were considered for the inner and outer surfaces, respectively, when the material properties varied along the radial direction but not through material thickness variations. A power law distribution was employed to represent the material properties. Three different methods were used to present the temperature distribution along the radial direction of the FG disk, namely (1) an in-house finite element (FE) program, (2) the ANSYS parametric design language (APDL), and (3) an analytical solution. Furthermore, the in-house FE program presented the thermal stress and thermal strain of the FG disk. The weighted residual method in the FEM was used to present the temperature distribution when the material properties along an element are varying in contrast with using a commercial finite element software when the material properties are constant within an element to simulate FGMs. The accuracy of the in-house FE program was tested, and it was shown that the temperature distributions obtained by using the abovementioned methods were exactly the same. A parametric material gradation study was performed to understand the effects on the temperature, thermal strain, and stress. The material gradation was found to have a significant effect in this regard. The in-house finite element program enables one to perform a post-processing analysis in a more efficient and convenient manner than that through simulations in a finite element software program such as ANSYS. Lastly, this in-house code can be used to perform an optimization analysis to minimize the thermal strain and stress while the stiffness of the plate is maintained when the material properties within an element vary