Teaching Mathematical Modeling in Mathematics Education

In the present paper we have discussed about mathematical modeling in mathematics education

Robot navigation and target capturing using nature-inspired approaches in a dynamic environment

Path Planning and target searching in a three-dimensional environment is a challenging task in the field of robotics. It is an optimization problem as the path from source to destination has to be optimal. This paper aims to generate a collision-free trajectory in a dynamic environment. The path planning problem has sought to be of extreme importance in the military, search and rescue missions and in life-saving tasks. During its operation, the unmanned air vehicle operates in a hostile environment, and faster replanning is needed to reach the target as optimally as possible. This paper presents a novel approach of hierarchical planning using multiresolution abstract levels for faster replanning. Economic constraints like path length, total path planning time and the number of turns are taken into consideration that mandate the use of cost functions. Experimental results show that the hierarchical version of GSO gives better performance compared to the BBO, IWO and their hierarchical versions.Comment: 8 pages, 8 figure

Design optimization in geometry of seismic mass for MEMS based cantilever type piezoelectric energy harvester for motor vibrations

Piezoelectric energy harvesters are suitable for vibration energy harvesting due to simple design, operation and fabrication in MEMS technology. Cantilever structures fixed from one end and seismic mass at the other must tune to different resonance frequency to ensure wideband frequency operation. Adequate width to length ratio of cantilever is required to avoid curling of cantilevers (bending). Effect of increase in width of the cantilever structure on resonance frequency has been investigated and also compared analytically in this paper. An optimized design has been proposed which compensates for the increase in resonance frequency due to increase in width by changing the geometry of the seismic mass. With the change in geometry of seismic mass a shift in center of mass has been achieved towards the free end of the cantilever which reduces the resonance frequency which is desirable. The design optimization of seismic mass reported in this paper reduces the resonance frequency by 4.27 % which is appreciated as it is required to harvest ambient vibrations having low frequency

Treatment of acute ischemic stroke in patients with and without atrial fibrillation

In the Netherlands, 21.000 patients per year are struck by an ischemic stroke. Stroke is a major cause of death and an important cause of hospital admission and long-term disability. Although case-fatality rates have steadily declined over the past 25 years, this is mainly due to improved general stroke management but not to new strategies to halt or reverse the harmful effects of brain ischemia. Stroke as a clinical syndrome was recognized even before the time of Hippocrates, but it was not until I 995 that the first effective treatment, thrombolysis with recombinant tissue plasminogen activator, became available. However, this treatment can be applied only to a small percentage of patients. For all others cases no effective treatment is available. In this thesis I shall describe and discuss two types of treatment for acute ischemic stroke, that were studied in randomized controlled trials. Firstly, we evaluated the safety, efficacy and pharmacodynamics of the use of a hemoglobin solution, diaspirin cross-linked hemoglobin (DCLHb) in a multicenter trial of patients with acute ischemic stroke. Secondly, we studied the effect of heparin in patients with acute ischemic stroke in combination with atrial fibrillation (AF) entered in a large clinical study, the International Stroke Trial (IST). We had specific interest in the prevention of early stroke recurrenc

Does A Short, Thick Neck Predict Obstructive Sleep Apnea?: The Role of Physical Examination in OSA Screening

Purpose: The purpose of this study was to determine whether a short neck, alone or together with a thick neck, can predict obstructive sleep apnea (OSA). Methods: The laryngeal heights of 169 new adult patients presenting to a sleep medicine physician were measured over a period of 5 months. Neck circumference, Mallampati score, and body-mass index (BMI) were also determined, together with medical history, smoking status, and serum bicarbonate. Lastly, patients’ polysomnograms were obtained in order to ascertain the presence or absence of OSA as indicated by the apnea-hypopnea index, as well as other sleep study parameters. Results: No association was found between laryngeal height and presence of OSA, bicarbonate concentration or oxygen saturation. Of interest, neck circumference was also not significantly associated with any of the aforementioned parameters, although there was a trend towards significance in its association with OSA (p=0.055). Still, a combined short laryngeal height and large neck circumference was associated with lower nadir SaO2 (p=0.018). Of all clinical parameters we measured, only higher BMI, older age and male sex were positively associated with OSA (p\u3c0.05). Conclusion: This study challenges the popular notion that short necks predict OSA

Mathematical Study of Risk Factors of Breast Cancer

In the present paper we study some literature and methodology on risk factors for breast cancer in women. This paper is based on modeling on cancer, especially breast cancer. We study the risk factors and forms mathematical equations using interpolation formulas. Key-words: risk factors, interpolation formula

Design and analysis of decagonal photonic crystal fiber with elliptical air hole core for liquid sensing

465-470In this paper, a decagonal geometry has been designed for liquid sensing. The liquid analytes that are sensed are ethanol, benzene and water as they are the most used analytes in the chemical and biological industries. Firstly, a decagonal structure has been designed and neff and sensitivity of this structure has been calculated. Then, the core structure has been modified and decagonal, octagonal and hexagonal geometries have been constructed inside the core with circular holes. Lastly, these circular holes have been replaced by elliptical holes. All the designed layouts have been analyzed and compared. The sensitivity obtained is of the order 40-50 % and confinement loss of order 10-9 dB/m which shows that these structures can be used for sensing ethanol, water and benzene and are reliable. For benzene, water and ethanol, the decagonal structure with core comprised of decagonal geometry, has been made of elliptical holes (x as major axis), gives the best results. For this geometry, the neff values are 1.379, 1.317 and 1.313 for benzene, ethanol and water, respectively. The sensitivity values obtained are 51.94%, 46.95%, and 44.45% and confinement loss value is 8.19 x 10-10, 1.03 x 10-10 and 1.069 x 10-7 dB/m, respectively

Controlled safety study of a hemoglobin-based oxygen carrier, DCLHb, in acute ischemic stroke

BACKGROUND AND PURPOSE: Diaspirin cross-linked hemoglobin (DCLHb) is a purified, cell-free human hemoglobin solution. In animal stroke models its use led to a significant reduction in the extent of brain injury. The primary objective of this study was to evaluate the safety of DCLHb in patients with acute ischemic stroke. METHODS: DCLHb or saline was administered to 85 patients with acute ischemic stroke in the anterior circulation, within 18 hours of onset of symptoms, in a multicenter, randomized, single-blind, dose-finding, controlled safety trial, consisting of 3 parts: 12 doses of 25, 50, and 100 mg/kg DCLHb over 72 hours. RESULTS: DCLHb caused a rapid rise in mean arterial blood pressure. The pressor effect was not accompanied by complications or excessive need for antihypertensive treatment. Two patients in the 100 mg/kg group had adverse events that were possibly drug related: one suffered fatal brain and pulmonary edema, the other transient renal and pancreatic insufficiency. Multivariate logistic regression analysis showed that a severe stroke at baseline and treatment with DCLHb (OR, 4.0; CI, 1.4 to 12.0) were independent predictors of a worse outcome (Rankin Scale score of 3 to 6) at 3 months. CONCLUSIONS: Outcome scale scores were worse in the DCLHb group, and more serious adverse events and deaths occurred in DCLHb-treated patients than in control patients. We recommend that additional safety studies be performed, preferably with a second generation, genetically engineered hemoglobin

Enhancement in structural, morphological and optical features of thermally annealed zinc oxide nanofilm

This paper presents the study of surface morphological, optical and microstructural features of zinc oxide (ZnO) nanofilm layered upon p-type Si substrate of <100> orientation by employing conventional RF magnetron sputtering system at different annealing temperatures. The effect of annealing on the nano-film is examined using different characterization techniques such as Atomic Force Microscopy (AFM), Scanning Electron Microscopy (SEM), X-ray Diffraction (XRD), FTIR (Fourier Transform Infrared Spectroscopy), UV-vis spectroscopy and Raman spectroscopy. The sharp diffraction peak at (002) orientation is seen by the XRD spectra which signifies a better growth of single crystalline thin film along the z-axis with the hexagonal wurtzite crystal structure. The surface morphological study shows that the grain size of the thin film intensifies from 22.06 nm to 36.77 nm when the annealing temperature is increased whereas there is a decrease in the values of lattice constants (a=b, c), FWHM (full width at half maximum), residual stress, lattice strain and dislocation density by increasing annealing temperature. The enhancement in the grain size makes the thin film appropriate for MEMS device applications including piezoelectric energy harvesters, gas sensors, etc. The optical bandgap of the ZnO thin film is estimated using Kubelka-Munk (KM) approach and it decreases from 3.23 to 3.16 eV for As-deposited, 400 °C, 600 °C and 800 °C respectively which makes the annealed thin film apposite for optoelectronic device applications. The intensity of the Raman peaks strengthens with the annealing temperature. These results prove that the annealing extensively enhances the crystallinity, structural, morphological and optical features of ZnO thin film and hence becomes suitable for nanoelectronic device applications

Enhancement in structural, morphological and optical features of thermally annealed zinc oxide nanofilm

642-648This paper presents the study of surface morphological, optical and microstructural features of zinc oxide (ZnO) nanofilm layered upon p-type Si substrate of orientation by employing conventional RF magnetron sputtering system at different annealing temperatures. The effect of annealing on the nano-film is examined using different characterization techniques such as Atomic Force Microscopy (AFM), Scanning Electron Microscopy (SEM), X-ray Diffraction (XRD), FTIR (Fourier Transform Infrared Spectroscopy), UV-vis spectroscopy and Raman spectroscopy. The sharp diffraction peak at (002) orientation is seen by the XRD spectra which signifies a better growth of single crystalline thin film along the z-axis with the hexagonal wurtzite crystal structure. The surface morphological study shows that the grain size of the thin film intensifies from 22.06 nm to 36.77 nm when the annealing temperature is increased whereas there is a decrease in the values of lattice constants (a=b, c), FWHM (full width at half maximum), residual stress, lattice strain and dislocation density by increasing annealing temperature. The enhancement in the grain size makes the thin film appropriate for MEMS device applications including piezoelectric energy harvesters, gas sensors, etc. The optical bandgap of the ZnO thin film is estimated using Kubelka-Munk (KM) approach and it decreases from 3.23 to 3.16 eV for As-deposited, 400 °C, 600 °C and 800 °C respectively which makes the annealed thin film apposite for optoelectronic device applications. The intensity of the Raman peaks strengthens with the annealing temperature. These results prove that the annealing extensively enhances the crystallinity, structural, morphological and optical features of ZnO thin film and hence becomes suitable for nanoelectronic device applications