Abstract: BEAMnrc was used to calculate the spectrum and
HVL for X-ray Beam during low energy X-ray radiation using tube model: SRO 33/100 /ROT 350 Philips. The results of BEAMnrc
simulation and measurements were compared to the IPEM report
number 78 and SpekCalc software. Three energies 127, 103 and 84
Kv were used. In these simulation a tungsten anode with 1.2 mm for
Be window were used as source. HVLs were calculated from
BEAMnrc spectrum with air Kerma method for four different filters.
For BEAMnrc one billion particles were used as original particles for
all simulations. The results show that for 127 kV, there was
maximum 5.2 % difference between BEAMnrc and Measurements
and minimum was 0.7% .the maximum 9.1% difference between
BEAMnrc and IPEM and minimum was 2.3% .The maximum
difference was 3.2% between BEAMnrc and SpekCal and minimum
was 2.8%. The result show BEAMnrc was able to satisfactory predict
the quantities of Low energy Beam as well as high energy X-ray
radiation.
Abstract: The aim of this study was to examine and identify the
type of Iranian financial market in terms of being symmetrical or
asymmetrical and to measure relationship between type of market
and the market's indices. In this study, daily information on the
market-s Share Price Index, Industrial Index and Top Fifty Most
Active Companies during the years 1999-2010 has been used. In
addition, to determine type of the financial market, rate of return on
Security is taken into account. In this research, by using logistic
regression analysis methods, relationship of the market type with the
above mentioned indices have been examined. The results showed
that the type of the financial market has a positive significant
association with market share price index and Industrial Index. Index
of Top Fifty Most Active Companies is significantly associated with
type of financial market, however this relationship is inverse.
Abstract: The experimental results on combustion of rice husk
in a conical fluidized bed combustor (referred to as the conical FBC)
using silica sand as the bed material are presented in this paper. The
effects of excess combustion air and combustor loading as well as the
sand bed height on the combustion pattern in FBC were investigated.
Temperatures and gas concentrations (CO and NO) along over the
combustor height as well as in the flue gas downstream from the ash
collecting cyclone were measured. The results showed that the axial
temperature profiles in FBC were explicitly affected by the
combustor loading whereas the excess air and bed height were found
to have minor influences on the temperature pattern. Meanwhile, the
combustor loading and the excess air significantly affected the axial
CO and NO concentration profiles; however, these profiles were
almost independent of the bed height. The combustion and thermal
efficiencies for this FBC were quantified for different operating
conditions.
Abstract: The production of biodiesel from crude palm oil with
a homogeneous base catalyst is unlikely owing to considerable
formation of soap. Free fatty acids (FFA) in crude palm oil need to
be reduced, e.g. by esterification. This study investigated the activity
of sulfated zirconia calcined at various temperatures for esterification
of FFA in crude palm oil to biodiesel. It was found that under a
proper reaction condition, sulfated zirconia well catalyzes
esterification. FFA content can be reduced to an acceptable value for
typical biodiesel production with a homogeneous base catalyst.
Crystallinity and sulfate attachment of sulfated zirconia depend on
calcination temperature during the catalyst preparation. Too low
temperature of calcination gives amorphous sulfated zirconia which
has low activity for esterification of FFA. In contrast, very high
temperature of calcination removes sulfate group, consequently,
conversion of FFA is reduced. The appropriate temperature range of
calcination is 550-650 oC.
Abstract: This study aims to determine the level of resistance of Hevea brasiliensis and Paraserianthes falcataria (synonym: Falcataria molucana) against wood rot fungi Pleurotus ostreatus based on Indonesian standard SNI 01.7207-2006 and Japanese standard JIS K 1571-2004. The variables measured were visual appearance and weight loss percentage of wood based on longitudinal and cross section fiber directions of rubber wood and sengon wood. Measurement of oven dry weight loss of wood samples performed after 12 weeks incubation. Replication performed was 10 times at each treatment combination. The results based on SNI 01.7207-2006, weight loss value of H. brasiliensis and P. falcataria wood with fiber direction longitudinal were 23,12 and 22,25% respectively and cross section were 20,77 and 18,76% respectively, and all were classified to resistance class IV (no resistance). The results based on JIS K 1571-2004, weight loss value of both woods with fiber direction cross section were 10,95 and 14,20% respectively.
Abstract: With the advent of new technologies, factors related to
mental health in e-workspaces are taken into consideration more than
ever. Studies have revealed that one of the factors affecting the
productivity of employees in an organization is occupational stress.
Another influential factor is quality of work life which is important in
the improvement of work environment conditions and organizational
efficiency. In order to uncover the quality of work life level and to
investigate the impact of occupational stress on quality of work life
among information technology employees in Iran, a cross-sectional
study design was applied and data were gathered using a
questionnaire validated by a group of experts. The results of the study
showed that information technology staffs have average level of both
occupational stress and quality of work life. Furthermore, it was
found that occupational stress has a negative impact on quality of
work life. In addition, the same results were observed for role
ambiguity, role conflict, role under-load, work-pace, work
repetitiveness and tension toward quality of work life. No significant
relation was found between role overload and quality of work life.
Finally, directions for future research are proposed and discussed.
Abstract: In this paper we are interested in classification problems
with a performance constraint on error probability. In such
problems if the constraint cannot be satisfied, then a rejection option
is introduced. For binary labelled classification, a number of SVM
based methods with rejection option have been proposed over the
past few years. All of these methods use two thresholds on the SVM
output. However, in previous works, we have shown on synthetic data
that using thresholds on the output of the optimal SVM may lead to
poor results for classification tasks with performance constraint. In
this paper a new method for supervised classification with rejection
option is proposed. It consists in two different classifiers jointly
optimized to minimize the rejection probability subject to a given
constraint on error rate. This method uses a new kernel based linear
learning machine that we have recently presented. This learning
machine is characterized by its simplicity and high training speed
which makes the simultaneous optimization of the two classifiers
computationally reasonable. The proposed classification method with
rejection option is compared to a SVM based rejection method
proposed in recent literature. Experiments show the superiority of
the proposed method.
Abstract: In this paper, free vibration analysis of carbon nanotube (CNT) reinforced laminated composite panels is presented. Three types of panels such as flat, concave and convex are considered for study. Numerical simulation is carried out using commercially available finite element analysis software ANSYS. Numerical homogenization is employed to calculate the effective elastic properties of randomly distributed carbon nanotube reinforced composites. To verify the accuracy of the finite element method, comparisons are made with existing results available in the literature for conventional laminated composite panels and good agreements are obtained. The results of the CNT reinforced composite materials are compared with conventional composite materials under different boundary conditions.
Abstract: This paper proposes a novel hybrid algorithm for feature selection based on a binary ant colony and SVM. The final subset selection is attained through the elimination of the features that produce noise or, are strictly correlated with other already selected features. Our algorithm can improve classification accuracy with a small and appropriate feature subset. Proposed algorithm is easily implemented and because of use of a simple filter in that, its computational complexity is very low. The performance of the proposed algorithm is evaluated through a real Rotary Cement kiln dataset. The results show that our algorithm outperforms existing algorithms.
Abstract: We propose a new approach on how to obtain the approximate solutions of Hamilton-Jacobi (HJ) equations. The process of the approximation consists of two steps. The first step is to transform the HJ equations into the virtual time based HJ equations (VT-HJ) by introducing a new idea of ‘virtual-time’. The second step is to construct the approximate solutions of the HJ equations through a computationally iterative procedure based on the VT-HJ equations. It should be noted that the approximate feedback solutions evolve by themselves as the virtual-time goes by. Finally, we demonstrate the effectiveness of our approximation approach by means of simulations with linear and nonlinear control problems.
Abstract: The growing health hazardous impact of arsenic (As)
contamination in environment is the impetus of the present
investigation. Application of lactic acid bacteria (LAB) for the
removal of toxic and heavy metals from water has been reported.
This study was performed in order to isolate and characterize the Asresistant
LAB from mud and sludge samples for using as efficient As
uptaking probiotic. Isolation of As-resistant LAB colonies was
performed by spread plate technique using bromocresol purple
impregnated-MRS (BP-MRS) agar media provided with As @ 50
μg/ml. Isolated LAB were employed for probiotic characterization
process, acid and bile tolerance, lactic acid production, antibacterial
activity and antibiotic tolerance assays. After As-resistant and
removal characterizations, the LAB were identified using 16S rDNA
sequencing. A total of 103 isolates were identified as As-resistant
strains of LAB. The survival of 6 strains (As99-1, As100-2, As101-3,
As102-4, As105-7, and As112-9) was found after passing through the
sequential probiotic characterizations. Resistant pattern pronounced
hollow zones at As concentration >2000 μg/ml in As99-1, As100-2,
and As101-3 LAB strains, whereas it was found at ~1000 μg/ml in
rest 3 strains. Among 6 strains, the As uptake efficiency of As102-4
(0.006 μg/h/mg wet weight of cell) was higher (17 – 209%)
compared to remaining LAB. 16S rDNA sequencing data of 3 (As99-
1, As100-2, and As101-3) and 3 (As102-4, As105-7, and As112-9)
LAB strains clearly showed 97 to 99% (340 bp) homology to
Pediococcus dextrinicus and Pediococcus acidilactici, respectively.
Though, there was no correlation between the metal resistant and
removal efficiency of LAB examined but identified elevated As
removing LAB would probably be a potential As uptaking probiotic
agent. Since present experiment concerned with only As removal
from pure water, As removal and removal mechanism in natural
condition of intestinal milieu should be assessed in future studies.
Abstract: Bus Rapid Transit (BRT) has emerged as a cost-effective transport system for urban mobility. However its ability to stimulate land development remains largely unexplored. The study makes use of qualitative (interview method) and quantitative analysis (questionnaire survey and longitudinal analysis of property data) to investigate land development impact resulting from BRT in Beijing, China. The empirical analysis suggests that BRT has a positive impact on the residential and commercial property attractiveness along the busway corridor. The statistical analysis suggests that accessibility advantage conferred by BRT is capitalized into higher property price. The average price of apartments adjacent to a BRT station has gained a relatively faster increase than those not served by the BRT system. The capitalization effect mostly occurs after the full operation of BRT, and is more evident over time and particularly observed in areas which previously lack alternative mobility opportunity.
Abstract: Pre-germinated parboiled brown rice or Khao hang (in Thai) is paddy which undergoing the processes of soaking, steaming, drying and dehusking to obtain the edible form for consumption. The objectives of this research were to study the kinetic of pre-germinated parboiled brown rice drying using fluidization technique and to study the properties of pre-germinated parboiled brown rice after drying. The dryings were performed at the different temperatures of 110, 120 and 130 oC at the bed depth of 2 cm with the air velocity of 1.98 m/s. The results found that the higher drying temperature led to the faster moisture reduction. After drying until the moisture content of pre-germinated parboiled brown rice was lower than 14%wet basis, samples were taken to determine various qualities such as percentage of head rice and L* a* b* color values. The shade drying was used as a control. The results found that the higher drying temperature resulted in the decrease of head rice percentage. For the color assessment, the trend of L* and a* values was increased with the drying temperature, while the b* value was not significantly difference (p › 0.05) by drying temperatures. However, the b value of drying by fluidized bed dryer was higher than the control.
Abstract: Numerical parametric study is conducted to study the effects of ampoule rotation on the flows and the dopant segregation in vertical bridgman (vb) crystal growth. Calculations were performed in unsteady state. The extended darcy model, which includes the time derivative and coriolis terms, has been employed in the momentum equation. It’s found that the convection, and dopant segregation can be affected significantly by ampoule rotation, and the effect is similar to that by an axial magnetic field. Ampoule rotation decreases the intensity of convection and stretches the flow cell axially. When the convection is weak, the flow can be suppressed almost completely by moderate ampoule rotation and the dopant segregation becomes diffusion-controlled. For stronger convection, the elongated flow cell by ampoule rotation may bring dopant mixing into the bulk melt reducing axial segregation at the early stage of the growth. However, if the cellular flow cannot be suppressed completely, ampoule rotation may induce larger radial segregation due to poor mixing.
Abstract: The Helmholtz equation often arises in the study of physical problems involving partial differential equation. Many researchers have proposed numerous methods to find the analytic or approximate solutions for the proposed problems. In this work, the exact analytical solutions of the Helmholtz equation in spherical polar coordinates are presented using the Nikiforov-Uvarov (NU) method. It is found that the solution of the angular eigenfunction can be expressed by the associated-Legendre polynomial and radial eigenfunctions are obtained in terms of the Laguerre polynomials. The special case for k=0, which corresponds to the Laplace equation is also presented.
Abstract: One of the most important parameters to develop and
manage urban areas is appropriate selection of land surface to
develop green spaces in these areas. In this study, in order to identify
the most appropriate sites and areas cultivated for ornamental species
in Jiroft, Landsat Enhanced Thematic Mapper Plus (ETM+) images
due to extract the most important effective climatic and adaphic
parameters for growth ornamental species were used. After geometric
and atmospheric corrections applied, to enhance accuracy of multi
spectral (XS) bands, the fusion of Landsat XS bands by IRS-1D
panchromatic band (PAN) was performed. After field sampling to
evaluate the correlation between different factors in surface soil
sampling location and different bands digital number (DN) of ETM+
sensor on the same points, correlation tables formed using the best
computational model and the map of physical and chemical
parameters of soil was produced. Then the accuracy of them was
investigated by using kappa coefficient. Finally, according to
produced maps, the best areas for cultivation of recommended
species were introduced.
Abstract: This study investigated morphology of the Spanner Barb (Puntius lateristriga Valenciennes, 1842) and water quality at Thepchana waterfall. This study was conducted at Thepchana Waterfall, Khao Nan National Park from March to May 2007. There were 40 Spanner Barb collected with 20 males and 20 females. Males had an average of 5.57 cm in standard length, 6.62 cm in total length and 5.18 g in total body weight. Females had an average of 7.25 cm in standard length, 8.24 cm in total length and 10.96 g in total body weight. The length (L) – weight (W) relationships for combining sexes, males and females were LogW = -2.137 + 3.355logL, log W = -0.068 + 3.297logL, and log W = -2.068 + 3.297logL, respectively. The Spanner Barb were smaller size fish with a compressed form; terminal mouth; villiform teeth; ctenoid scale; concave tail; general body color yellowish olive, with slight reddish tint to fins; vertical band beginning below dorsal and horizontal stripe from base of tail almost to vertical band. They also had a vertical band midway between the eye and first vertical band. There was a black spot above anal fin. The bladder looked like J-shape. Inside of the bladder was found small insects and insect lava. The body length and the bowels length was 1:1 ratio. The water temperature ranged from 25.00 – 27.00 °C which was appropriate for their habitat characteristics. Acid - alkalinity ranged from 6.65 – 6.90 mg/l. Dissolved oxygen ranged from 4.55 – 4.70 mg/l. Water hardness ranged from 31.00 – 48.00 mg/l. The amount of ammonia was about 0.25 mg/l.
Abstract: In this study, ZnO nano rods and ZnO ultrafine particles were synthesized by Gel-casting method. The synthesized ZnO powder has a hexagonal zincite structure. The ZnO aggregates with rod-like morphology are typically 1.4 μm in length and 120 nm in diameter, which consist of many small nanocrystals with diameters of 10 nm. Longer wires connected by many hexahedral ZnO nanocrystals were obtained after calcinations at the temperature over 600° C.The crystalline structures and morphologies of the powder have been characterized by X-ray diffraction(XRD) and Scaning electron microscopy (SEM).The result shows that the different preparation conditions such as concentration H2O, calcinations time and calcinations temperature have a lot of influences upon the properties of nano ZnO powders, an increase in the temperature of the calcinations results in an increase of the grain size and also the increase of the calcinations time in high temperature makes the size of the grains bigger. The existences of extra watter prevent nano grains from improving like rod morphology. We have obtained the smallest grain size of ZnO powder by controlling the process conditions. Finally In a suitable condition, a novel nanostructure, namely bi-rod-like ZnO nano rods was found which is different from known ZnO nanostructures.
Abstract: Green Roofs offers numerous advantages, including lowering ambient temperature, which is of increasing interest due to global warming concerns. However, there are technical problems pertaining to waterproofing to be resolved. Currently, the only recognized green roof waterproofing test is the German standard FLL. This paper examines the potential of replicating the test in tropical climate and reducing the test duration by using pre-grown plants. A three year old sample and a new setup were used for this experimental study. The new setup was prepared with close reference to the FLL standards and was compared against the three year old sample. Results showed that the waterproofing membrane was damaged by plant roots in both setups. Joints integrity was also challenged.
Abstract: Parametric models have been quite popular for
studying human growth, particularly in relation to biological
parameters such as peak size velocity and age at peak size velocity.
Longitudinal data are generally considered to be vital for fittinga
parametric model to individual-specific data, and for studying the
distribution of these biological parameters in a human population.
However, cross-sectional data are easier to obtain than longitudinal
data. In this paper, we present a method of combining longitudinal
and cross-sectional data for the purpose of estimating the distribution
of the biological parameters. We demonstrate, through simulations in
the special case ofthePreece Baines model, how estimates based on
longitudinal data can be improved upon by harnessing the
information contained in cross-sectional data.We study the extent of
improvement for different mixes of the two types of data, and finally
illustrate the use of the method through data collected by the Indian
Statistical Institute.