Abstract: The unsteady wake of an EPPLER 361 airfoil in
pitching motion has been investigated in a subsonic wind tunnel by
hot-wire anemometry. The airfoil was given the pitching motion
about the one-quarter chord axis at reduced frequency of 0182.
Streamwise mean velocity profiles (wake profiles) were investigated
at several vertically aligned points behind the airfoil at one-quarter
chord downstream distance from trailing edge. Oscillation amplitude
and mean angle of attack were varied to determine the effects on
wake profiles. When the maximum dynamic angle of attack was
below the static stall angle of attack, weak effects on wake were
found by increasing oscillation amplitude and mean angle of attack.
But, for higher angles of attack strong unsteady effects were
appeared on the wake.
Abstract: Properly sized capacitor banks are connected across induction motors for several reasons including power factor correction, reducing distortions, increasing capacity, etc. Total harmonic distortion (THD) and power factor (PF) are used in such cases to quantify the improvements obtained through connection of the external capacitor banks. On the other hand, one of the methods for assessing the motor internal condition is by the use of Park-s pattern analysis. In spite of taking adequate precautionary measures, the capacitor banks may sometimes malfunction. Such a minor fault in the capacitor bank is often not apparently discernible. This may however, give rise to substantial degradation of power factor correction performance and may also damage the supply profile. The case is more severe with the fact that the Park-s pattern gets distorted due to such external capacitor faults, and can give anomalous results about motor internal fault analyses. The aim of this paper is to present simulation and hardware laboratory test results to have an understanding of the anomalies in harmonic distortion and Park-s pattern analyses in induction motors due to capacitor bank defects.
Abstract: This paper present some preliminary work on the
preparation and physicochemical caracterization of nanocomposite
MFI-alumina structures based on alumina hollow fibres. The fibers
are manufactured by a wet spinning process. α-alumina particles were
dispersed in a solution of polysulfone in NMP. The resulting slurry is
pressed through the annular gap of a spinneret into a precipitation
bath. The resulting green fibres are sintered. The mechanical strength
of the alumina hollow fibres is determined by a three-point-bending
test while the pore size is characterized by bubble-point testing. The
bending strength is in the range of 110 MPa while the average pore
size is 450 nm for an internal diameter of 1 mm and external diameter
of 1.7 mm. To characterize the MFI membranes various techniques
were used for physicochemical characterization of MFI–ceramic
hollow fibres membranes: The nitrogen adsorption, X-ray
diffractometry, scanning electron microscopy combined with X
emission microanalysis. Scanning Electron Microscopy (SEM) and
Energy Dispersive Microanalysis by the X-ray were used to observe
the morphology of the hollow fibre membranes (thickness,
infiltration into the carrier, defects, homogeneity). No surface film,
has been obtained, as observed by SEM and EDX analysis and
confirmed by high temperature variation of N2 and CO2 gas
permeances before cation exchange. Local analysis and characterise
(SEM and EDX) and overall (by ICP elemental analysis) were
conducted on two samples exchanged to determine the quantity and
distribution of the cation of cesium on the cross section fibre of the
zeolite between the cavities.
Abstract: This paper presents the experimental results of
comparison between leakage currents and discharge currents. The leakage currents were obtained on polluted porcelain insulator.
Whereas, the discharge currents were obtained on lightly artificial
polluted porcelain specimen. The conducted measurements were
leakage current or discharge current and applied voltage. The insulator or specimen was in a hermetically sealed chamber, and the
current waveforms were analyzed using FFT.
The result indicated that the leakage current (LC) on low RH condition the fifth harmonic would be visible, and followed by the
seventh harmonic. The insulator had capacitive property. Otherwise,
on 99% relative humidity, the fifth harmonic would also be visible,
and the phase angle reached up to 12.2 degree. Whereas, on discharge current, the third harmonic would be visible, and followed
by fifth harmonic. The third harmonic would increase as pressure reduced. On this condition, the specimen had a non-linear characteristics
Abstract: Research results and optimal parameters investigation
of laser cut and profiling of diamond and quartz substrates by
femtosecond laser pulses are presented. Profiles 10 μm in width, ~25
μm in depth and several millimeters long were made. Investigation of
boundaries quality has been carried out with the use of AFM
«Vecco». Possibility of technological formation of profiles and
micro-holes in diamond and quartz substrates with nanometer-scale
boundaries is shown. Experimental results of multilayer dielectric
cover treatment are also presented. Possibility of precise upper layer
(thickness of 70–140 nm) removal is demonstrated. Processes of thin
metal film (60 nm and 350 nm thick) treatment are considered.
Isolation tracks (conductance ~ 10-11 S) 1.6–2.5 μm in width in
conductive metal layers are formed.
Abstract: Thousands of masters athletes participate
quadrennially in the World Masters Games (WMG), yet this cohort
of athletes remains proportionately under-investigated. Due to a
growing global obesity pandemic in context of benefits of physical
activity across the lifespan, the BMI trends for this unique population
was of particular interest. The nexus between health, physical
activity and aging is complex and has raised much interest in recent
times due to the realization that a multifaceted approach is necessary
in order to counteract the obesity pandemic. By investigating age
based trends within a population adhering to competitive sport at
older ages, further insight might be gleaned to assist in understanding
one of many factors influencing this relationship.BMI was derived
using data gathered on a total of 6,071 masters athletes (51.9% male,
48.1% female) aged 25 to 91 years ( =51.5, s =±9.7), competing at
the Sydney World Masters Games (2009). Using linear and loess
regression it was demonstrated that the usual tendency for prevalence
of higher BMI increasing with age was reversed in the sample. This
trend in reversal was repeated for both male and female only sub-sets
of the sample participants, indicating the possibility of improved
prevalence of BMI with increasing age for both the sample as a
whole and these individual sub-groups.This evidence of improved
classification in one index of health (reduced BMI) for masters
athletes (when compared to the general population) implies there are
either improved levels of this index of health with aging due to
adherence to sport or possibly the reduced BMI is advantageous and
contributes to this cohort adhering (or being attracted) to masters
sport at older ages.
Abstract: Life is beautiful. But, it is decided by genes, environment and the individual and shattered by the natural and / or the invited problems. Most of the global rural helpless masses are struggling for their survival since; they are neglected in all aspects of life including health. Amidst a countless number of miserable diseases in man, diabetes is becoming a dreaded killer and ramifying the entire globe in a jet speed. Diabetes control continues as a Herculean task to the scientific community and the modern society in the 21st century also. T2DM is not pertaining to any age and it can develop even during the childhood. This multifactorial disease abruptly changes the activities of certain vital biomarkers in the present rural T2DM cases. A remarkable variation in the levels of biomarkers like AST, ALT, GGT, ALP, LDH, HbA1C, C- peptide, fasting sugar, post-prandial sugar, sodium, potassium, BUN, creatinine and insulin show the rampant nature of T2DM in this physically active rural agrarian community.
Abstract: The research investigates the “impact of VLE on mathematical concepts acquisition of the special education needs (SENs) students at KS4 secondary education sector" in England. The overall aim of the study is to establish possible areas of difficulties to approach for above or below knowledge standard requirements for KS4 students in the acquisition and validation of basic mathematical concepts. A teaching period, in which virtual learning environment (Fronter) was used to emphasise different mathematical perception and symbolic representation was carried out and task based survey conducted to 20 special education needs students [14 actually took part]. The result shows that students were able to process information and consider images, objects and numbers within the VLE at early stages of acquisition process. They were also able to carry out perceptual tasks but with limiting process of different quotient, thus they need teacher-s guidance to connect them to symbolic representations and sometimes coach them through. The pilot study further indicates that VLE curriculum approaches for students were minutely aligned with mathematics teaching which does not emphasise the integration of VLE into the existing curriculum and current teaching practice. There was also poor alignment of vision regarding the use of VLE in realisation of the objectives of teaching mathematics by the management. On the part of teacher training, not much was done to develop teacher-s skills in the technical and pedagogical aspects of VLE that is in-use at the school. The classroom observation confirmed teaching practice will find a reliance on VLE as an enhancer of mathematical skills, providing interaction and personalisation of learning to SEN students.
Abstract: Wavelet transforms is a very powerful tools for image compression. One of its advantage is the provision of both spatial and frequency localization of image energy. However, wavelet transform coefficients are defined by both a magnitude and sign. While algorithms exist for efficiently coding the magnitude of the transform coefficients, they are not efficient for the coding of their sign. It is generally assumed that there is no compression gain to be obtained from the coding of the sign. Only recently have some authors begun to investigate the sign of wavelet coefficients in image coding. Some authors have assumed that the sign information bit of wavelet coefficients may be encoded with the estimated probability of 0.5; the same assumption concerns the refinement information bit. In this paper, we propose a new method for Separate Sign Coding (SSC) of wavelet image coefficients. The sign and the magnitude of wavelet image coefficients are examined to obtain their online probabilities. We use the scalar quantization in which the information of the wavelet coefficient to belong to the lower or to the upper sub-interval in the uncertainly interval is also examined. We show that the sign information and the refinement information may be encoded by the probability of approximately 0.5 only after about five bit planes. Two maps are separately entropy encoded: the sign map and the magnitude map. The refinement information of the wavelet coefficient to belong to the lower or to the upper sub-interval in the uncertainly interval is also entropy encoded. An algorithm is developed and simulations are performed on three standard images in grey scale: Lena, Barbara and Cameraman. Five scales are performed using the biorthogonal wavelet transform 9/7 filter bank. The obtained results are compared to JPEG2000 standard in terms of peak signal to noise ration (PSNR) for the three images and in terms of subjective quality (visual quality). It is shown that the proposed method outperforms the JPEG2000. The proposed method is also compared to other codec in the literature. It is shown that the proposed method is very successful and shows its performance in term of PSNR.
Abstract: One of the main challenges for one phase anaerobic digestion processes is the high concentration of NH4+ and PO4 3- ions
in the digested sludge supernatant. This project focuses on enhancing the removal of nutrients during the anaerobic digestion process through fixing both NH4+ and PO4 3- ions in the form of struvite (magnesium ammonium phosphate, MAP, MgNH4PO4.6H2O) within the anaerobic sludge. Batch anaerobic digestion tests showed that Mg2+ concentration in the range 279 – 812 mg/L had insignificant effect on CGP but incurred a slight increase in COD removal. The reactor that had soluble Mg2+:NH4+:PO43- at a molar ratio of 1.28:1:00:1:00 achieved the best performance enhancement of 8% increase in COD removal and 32% reduction in NH4+ in the reactor supernatant. Overall, the results show that there is a potential to optimise conventional anaerobic digestion such that supernatant lean in P and N, and sludge rich in nutrients are obtained.
Abstract: Human immunodeficiency virus infection and
acquired immunodeficiency syndrome is a global pandemic with
cases reporting from virtually every country and continues to be a
common infection in developing country like India.
Microalbuminuria is a manifestation of human immunodeficiency
virus associated nephropathy. Therefore, microalbuminuria may be
an early marker of human immunodeficiency virus associated
nephropathy, and screening for its presence may be beneficial. A
strikingly high prevalence of microalbuminuria among human
immunodeficiency virus infected patients has been described in
various studies. Risk factors for clinically significant proteinuria
include African - American race, higher human immunodeficiency
virus ribonucleic acid level and lower CD4 lymphocyte count. The
cardiovascular risk factors of increased systolic blood pressure and
increase fasting blood sugar level are strongly associated with
microalbuminuria in human immunodeficiency virus patient. These
results suggest that microalbuminuria may be a sign of current
endothelial dysfunction and micro-vascular disease and there is
substantial risk of future cardiovascular disease events. Positive
contributing factors include early kidney disease such as human
immunodeficiency virus associated nephropathy, a marker of end
organ damage related to co morbidities of diabetes or hypertension,
or more diffuse endothelial cells dysfunction. Nevertheless after
adjustment for non human immunodeficiency virus factors, human
immunodeficiency virus itself is a major risk factor. The presence of
human immunodeficiency virus infection is independent risk to
develop microalbuminuria in human immunodeficiency virus patient.
Cardiovascular risk factors appeared to be stronger predictors of
microalbuminuria than markers of human immunodeficiency virus
severity person with human immunodeficiency virus infection and
microalbuminuria therefore appear to potentially bear the burden of
two separate damage related to known vascular end organ damage
related to know vascular risk factors, and human immunodeficiency
virus specific processes such as the direct viral infection of kidney
cells.The higher prevalence of microalbuminuria among the human
immunodeficiency virus infected could be harbinger of future
increased risks of both kidney and cardiovascular disease. Further
study defining the prognostic significance of microalbuminuria
among human immunodeficiency virus infected persons will be
essential. Microalbuminuria seems to be a predictor of cardiovascular
disease in diabetic and non diabetic subjects, hence it can also be
used for early detection of micro vascular disease in human
immunodeficiency virus positive patients, thus can help to diagnose
the disease at the earliest.
Abstract: In this study, stress distributions on dental implants
made of functionally graded biomaterials (FGBM) are investigated
numerically. The implant body is considered to be subjected to axial
compression loads. Numerical problem is assumed to be 2D, and
ANSYS commercial software is used for the analysis. The cross
section of the implant thread varies as varying the height (H) and the
width (t) of the thread. According to thread dimensions of implant
and material properties of FGBM, equivalent stress distribution on
the implant is determined and presented with contour plots along
with the maximum equivalent stress values. As a result, with
increasing material gradient parameter (n), the equivalent stress
decreases, but the minimum stress distribution increases. Maximum
stress values decrease with decreasing implant radius (r). Maximum
von Mises stresses increases with decreasing H when t is constant.
On the other hand, the stress values are not affected by variation of t
in the case of H = constant.
Abstract: In this paper, we propose ablock-wise watermarking scheme for color image authentication to resist malicious tampering of digital media. The thresholding technique is incorporated into the scheme such that the tampered region of the color image can be recovered with high quality while the proofing result is obtained. The watermark for each block consists of its dual authentication data and the corresponding feature information. The feature information for recovery iscomputed bythe thresholding technique. In the proofing process, we propose a dual-option parity check method to proof the validity of image blocks. In the recovery process, the feature information of each block embedded into the color image is rebuilt for high quality recovery. The simulation results show that the proposed watermarking scheme can effectively proof the tempered region with high detection rate and can recover the tempered region with high quality.
Abstract: Leptospirosis is recognized as an important zoonosis
in tropical regions well as an important animal disease with
substantial loss in production. In this study, the model for the
transmission of the Leptospirosis disease to human population are
discussed. Model is described the vector population dynamics and
the Leptospirosis transmission to the human population are
discussed. Local analysis of equilibria are given. We confirm the
results by using numerical results.
Abstract: When acid is pumped into damaged reservoirs for
damage removal/stimulation, distorted inflow of acid into the
formation occurs caused by acid preferentially traveling into highly
permeable regions over low permeable regions, or (in general) into
the path of least resistance. This can lead to poor zonal coverage and
hence warrants diversion to carry out an effective placement of acid.
Diversion is desirably a reversible technique of temporarily reducing
the permeability of high perm zones, thereby forcing the acid into
lower perm zones.
The uniqueness of each reservoir can pose several challenges to
engineers attempting to devise optimum and effective diversion
strategies. Diversion techniques include mechanical placement and/or
chemical diversion of treatment fluids, further sub-classified into ball
sealers, bridge plugs, packers, particulate diverters, viscous gels,
crosslinked gels, relative permeability modifiers (RPMs), foams,
and/or the use of placement techniques, such as coiled tubing (CT)
and the maximum pressure difference and injection rate (MAPDIR)
methodology.
It is not always realized that the effectiveness of diverters greatly
depends on reservoir properties, such as formation type, temperature,
reservoir permeability, heterogeneity, and physical well
characteristics (e.g., completion type, well deviation, length of
treatment interval, multiple intervals, etc.). This paper reviews the
mechanisms by which each variety of diverter functions and
discusses the effect of various reservoir properties on the efficiency
of diversion techniques. Guidelines are recommended to help
enhance productivity from zones of interest by choosing the best
methods of diversion while pumping an optimized amount of
treatment fluid. The success of an overall acid treatment often
depends on the effectiveness of the diverting agents.
Abstract: The objectives of this research paper were to study the
influencing factors that contributed to the success of electronic
commerce (e-commerce) and to study the approach to enhance the
standard of e-commerce for small and medium enterprises (SME).
The research paper focused the study on only sole proprietorship
SMEs in Bangkok, Thailand. The factors contributed to the success
of SME included business management, learning in the organization,
business collaboration, and the quality of website. A quantitative and
qualitative mixed research methodology was used. In terms of
quantitative method, a questionnaire was used to collect data from
251 sole proprietorships. The System Equation Model (SEM) was
utilized as the tool for data analysis. In terms of qualitative method,
an in-depth interview, a dialogue with experts in the field of ecommerce
for SMEs, and content analysis were used.
By using the adjusted causal relationship structure model, it was
revealed that the factors affecting the success of e-commerce for
SMEs were found to be congruent with the empirical data. The
hypothesis testing indicated that business management influenced the
learning in the organization, the learning in the organization
influenced business collaboration and the quality of the website, and
these factors, in turn, influenced the success of SMEs. Moreover, the
approach to enhance the standard of SMEs revealed that the majority
of respondents wanted to enhance the standard of SMEs to a high
level in the category of safety of e-commerce system, basic structure
of e-commerce, development of staff potentials, assistance of budget
and tax reduction, and law improvement regarding the e-commerce
respectively.
Abstract: X-ray mammography is the most effective method for
the early detection of breast diseases. However, the typical diagnostic
signs such as microcalcifications and masses are difficult to detect
because mammograms are of low-contrast and noisy. In this paper, a
new algorithm for image denoising and enhancement in Orthogonal
Polynomials Transformation (OPT) is proposed for radiologists to
screen mammograms. In this method, a set of OPT edge coefficients
are scaled to a new set by a scale factor called OPT scale factor. The
new set of coefficients is then inverse transformed resulting in
contrast improved image. Applications of the proposed method to
mammograms with subtle lesions are shown. To validate the
effectiveness of the proposed method, we compare the results to
those obtained by the Histogram Equalization (HE) and the Unsharp
Masking (UM) methods. Our preliminary results strongly suggest
that the proposed method offers considerably improved enhancement
capability over the HE and UM methods.
Abstract: With the explosive growth of information sources available on the World Wide Web, it has become increasingly difficult to identify the relevant pieces of information, since web pages are often cluttered with irrelevant content like advertisements, navigation-panels, copyright notices etc., surrounding the main content of the web page. Hence, tools for the mining of data regions, data records and data items need to be developed in order to provide value-added services. Currently available automatic techniques to mine data regions from web pages are still unsatisfactory because of their poor performance and tag-dependence. In this paper a novel method to extract data items from the web pages automatically is proposed. It comprises of two steps: (1) Identification and Extraction of the data regions based on visual clues information. (2) Identification of data records and extraction of data items from a data region. For step1, a novel and more effective method is proposed based on visual clues, which finds the data regions formed by all types of tags using visual clues. For step2 a more effective method namely, Extraction of Data Items from web Pages (EDIP), is adopted to mine data items. The EDIP technique is a list-based approach in which the list is a linear data structure. The proposed technique is able to mine the non-contiguous data records and can correctly identify data regions, irrespective of the type of tag in which it is bound. Our experimental results show that the proposed technique performs better than the existing techniques.
Abstract: In this paper, the solubility of CO2 in AMP solution
have been measured at temperature range of ( 293, 303 ,313,323)
K.The amine concentration ranges studied are (2.0, 2.8, and 3.4) M.
A solubility apparatus was used to measure the solubility of CO2 in
AMP solution on samples of flue gases from Thermal and Central
Power Plants of Esfahan Steel Company. The modified Kent
Eisenberg model was used to correlate and predict the vapor-liquid
equilibria of the (CO2 + AMP + H2O) system. The model predicted
results are in good agreement with the experimental vapor-liquid
equilibrium measurements.
Abstract: A new fuzzy filter is presented for noise reduction of
images corrupted with additive noise. The filter consists of two
stages. In the first stage, all the pixels of image are processed for
determining noisy pixels. For this, a fuzzy rule based system
associates a degree to each pixel. The degree of a pixel is a real
number in the range [0,1], which denotes a probability that the pixel
is not considered as a noisy pixel. In the second stage, another fuzzy
rule based system is employed. It uses the output of the previous
fuzzy system to perform fuzzy smoothing by weighting the
contributions of neighboring pixel values. Experimental results are
obtained to show the feasibility of the proposed filter. These results
are also compared to other filters by numerical measure and visual
inspection.