Abstract: A rigorous two-dimensional model is developed for simulating the operation of a less-investigated type steam reformer having a considerably lower operating Reynolds number, higher tube diameter, and non-availability of extra steam in the feed compared with conventional steam reformers. Simulation results show that reasonable predictions can only be achieved when certain correlations for wall to fluid heat transfer equations are applied. Due to severe operating conditions, in all cases, strong radial temperature gradients inside the reformer tubes have been found. Furthermore, the results show how a certain catalyst loading profile will affect the operation of the reformer.
Abstract: Since 2005, an SRF module of CESR type serves as the
accelerating cavity at the Taiwan Light Source in the National
Synchrotron Radiation Research Center. A 500-MHz niobium cavity
is immersed in liquid helium inside this SRF module. To reduce heat
load, the liquid helium vessel is thermally shielded by
liquid-nitrogen-cooled copper layer, and the beam chambers are also
anchored with pipes of the liquid nitrogen flow in middle of the liquid
helium vessel and the vacuum vessel. A strong correlation of the
movement of the cavity-s frequency tuner with the temperature
variation of parts cooled with liquid nitrogen was observed. A
previous study on a spare SRF module with the niobium cavity cooled
by liquid nitrogen instead of liquid helium, satisfactory suppression of
the thermal oscillation was achieved by attaching a temporary buffer
tank for the vented shielding nitrogen flow from the SRF module. In
this study, a home-made buffer tank is designed and integrated to the
spare SRF module with cavity cooled by liquid helium. Design,
construction, integration, and preliminary test results of this buffer
tank are presented.
Abstract: In order to enhance the knowledge of certain
phytochemical Algerian plants that are widely used in traditional
medicine and to exploit their therapeutic potential in modern
medicine, we have done a specific extraction of terpenes and
alkaloids from the leaves of Euphorbia granulata to evaluate the
antioxidant and antibacterial activity of this extracts. After the
extraction it was found that the terpene extract gave the highest yield
59.72% compared with alkaloids extracts.
The disc diffusion method was used to determine the antibacterial
activity against different bacterial strains: Escherichia coli
(ATCC25922), Pseudomonas aeruginosa (ATCC27853) and
Staphylococcus aureus (ATCC25923). All extracts have shown
inhibition of growth bacteria. The different zones of inhibition have
varied from (7 -10 mm) according to the concentrations of extract
used.
Testing the antiradical activity on DPPH-TLC plates indicated the
presence of substances that have potent anti-free radical. As against,
the BC-TLC revealed that only terpenes extract which was reacted
positively. These results can validate the importance of Euphorbia
granulata in traditional medicine.
Abstract: This paper presents probabilistic horizontal seismic
hazard assessment of Naghan, Iran. It displays the probabilistic
estimate of Peak Ground Horizontal Acceleration (PGHA) for the
return period of 475, 950 and 2475 years. The output of the
probabilistic seismic hazard analysis is based on peak ground
acceleration (PGA), which is the most common criterion in designing
of buildings. A catalogue of seismic events that includes both
historical and instrumental events was developed and covers the
period from 840 to 2009. The seismic sources that affect the hazard
in Naghan were identified within the radius of 200 km and the
recurrence relationships of these sources were generated by Kijko
and Sellevoll. Finally Peak Ground Horizontal Acceleration (PGHA)
has been prepared to indicate the earthquake hazard of Naghan for
different hazard levels by using SEISRISK III software.
Abstract: This study assesses the vulnerability of Bulgarian
agriculture to drought using the WINISAREG model and seasonal
standard precipitation index SPI(2) for the period 1951-2004. This
model was previously validated for maize on soils of different water
holding capacity (TAW) in various locations. Simulations are
performed for Plovdiv, Stara Zagora and Sofia. Results relative to
Plovdiv show that in soils of large TAW (180 mm m-1) net irrigation
requirements (NIRs) range 0-40 mm in wet years and 350-380 mm in
dry years. In soils of small TAW (116 mm m-1), NIRs reach 440 mm
in the very dry year. NIRs in Sofia are about 80 mm smaller. Rainfed
maize is associated with great yield variability (29%
Abstract: Parallel Prefix addition is a technique for improving
the speed of binary addition. Due to continuing integrating intensity
and the growing needs of portable devices, low-power and highperformance
designs are of prime importance. The classical parallel
prefix adder structures presented in the literature over the years
optimize for logic depth, area, fan-out and interconnect count of logic
circuits. In this paper, a new architecture for performing 8-bit, 16-bit
and 32-bit Parallel Prefix addition is proposed. The proposed prefix
adder structures is compared with several classical adders of same
bit width in terms of power, delay and number of computational
nodes. The results reveal that the proposed structures have the least
power delay product when compared with its peer existing Prefix
adder structures. Tanner EDA tool was used for simulating the adder
designs in the TSMC 180 nm and TSMC 130 nm technologies.
Abstract: This paper describes an experimental investigation of
the drying behavior and conditions of rosehip in a convective
cyclone-type dryer. Drying experiments were conducted at air inlet
temperatures of 50, 60 and 70 o C and air velocities of 0.5, 1 and 1.5
ms–1. The parametric values obtained from the experiments were
fitted to the Newton mathematical models. Consequently, the drying
model developed by Newton model showed good agreement with the
data obtained from the experiments. Concluding, it was obtained that;
(i) the temperature is the major effect on the drying process, (ii) air
velocity has low effect on the drying of rosehip, (iii) the C-vitamin is
observed to change according to the temperature, moisture, drying
time and flow types. The changing ratio is found to be in the range of
0.70-0.74.
Abstract: Elateriospermum tapos seed (buah perah) is the one
of the rich sources of polyunsaturated fatty acids. It contains high
percentage of oleic acid which is the important component to develop
nervous system and also α-linolenic acid (ALA) which is the
precursor of omega-3 fatty acids series to synthesize
eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA).
However, there is less study about this valuable oilseed and exploit
its potential. Therefore, this paper is to assess the comparison of
physico-chemical properties and fatty composition of perah oil to
palm oil and soybean oil. From the comparison, perah oil shows low
peroxide value means it has good oxidative stability and also high
iodine values shows that it can be used in paint industry. The study
shown that perah oil is comparable to palm oil and soybean oil, so it
has high potential to be exploited in the oleochemical,
pharmaceutical, cosmetics and paint industries.
Abstract: A new distance-adjusted approach is proposed in
which static square contours are defined around an estimated
symbol in a QAM constellation, which create regions that
correspond to fixed step sizes and weighting factors. As a
result, the equalizer tap adjustment consists of a linearly
weighted sum of adaptation criteria that is scaled by a variable
step size. This approach is the basis of two new algorithms: the
Variable step size Square Contour Algorithm (VSCA) and the
Variable step size Square Contour Decision-Directed
Algorithm (VSDA). The proposed schemes are compared with
existing blind equalization algorithms in the SCA family in
terms of convergence speed, constellation eye opening and
residual ISI suppression. Simulation results for 64-QAM
signaling over empirically derived microwave radio channels
confirm the efficacy of the proposed algorithms. An RTL
implementation of the blind adaptive equalizer based on the
proposed schemes is presented and the system is configured to
operate in VSCA error signal mode, for square QAM signals
up to 64-QAM.
Abstract: Fractional-order controller was proven to perform better than the integer-order controller. However, the absence of a pole at origin produced marginal error in fractional-order control system. This study demonstrated the enhancement of the fractionalorder PI over the integer-order PI in a steam temperature control. The fractional-order controller was cascaded with an error compensator comprised of a very small zero and a pole at origin to produce a zero steady-state error for the closed-loop system. Some modification on the error compensator was suggested for different order fractional integrator that can improve the overall phase margin.
Abstract: One of the most importance of intelligence in-car and
roadside systems is the cooperative vehicle-infrastructure system. In
Thailand, ITS technologies are rapidly growing and real-time vehicle
information is considerably needed for ITS applications; for example,
vehicle fleet tracking and control and road traffic monitoring
systems. This paper defines the communication protocols and
software design for middleware components of B-VIS (Burapha
Vehicle-Infrastructure System). The proposed B-VIS middleware architecture serves the needs of a distributed RFID sensor network and simplifies some intricate details of several communication standards.
Abstract: Owing to the stringent environmental legislations,
CO2 capture and sequestration is one of the viable solutions to reduce
the CO2 emissions from various sources. In this context, Ionic liquids
(ILs) are being investigated as suitable absorption media for CO2
capture. Due to their non-evaporative, non-toxic, and non-corrosive
nature, these ILs have the potential to replace the existing solvents
like aqueous amine solutions for CO2 separation technologies. Thus,
the present work aims at studying the important aspects such as the
interactions of CO2 molecule with different anions (F-, Br-, Cl-, NO3
-,
BF4
-, PF6
-, Tf2N-, and CF3SO3
-) that are commonly used in ILs
through molecular modeling. In this, the minimum energy structures
have been obtained using Ab initio based calculations at MP2
(Moller-Plesset perturbation) level. Results revealed various degrees
of distortion of CO2 molecule (from its linearity) with the anions
studied, most likely due to the Lewis acid-base interactions between
CO2 and anion. Furthermore, binding energies for the anion-CO2
complexes were also calculated. The implication of anion-CO2
interactions to the solubility of CO2 in ionic liquids is also discussed.
Abstract: There has been gradual progress of late in construction projects, particularly in big-scale megaprojects. Due to the long-term construction period, however, with large-scale budget investment, lack of construction management technologies, and increase in the incomplete elements of project schedule management, a plan to conduct efficient operations and to ensure business safety is required. In particular, as the project management information system (PMIS) is meant for managing a single project centering on the construction phase, there is a limitation in the management of program-scale businesses like megaprojects. Thus, a program management information system (PgMIS) that includes program-level management technologies is needed to manage multiple projects. In this study, a support tool was developed for managing the cost and schedule information occurring in the construction phase, at the program level. In addition, a case study on the developed support tool was conducted to verify the usability of the system. With the use of the developed support tool program, construction managers can monitor the progress of the entire project and of the individual subprojects in real time.
Abstract: The aim of this study is to describe the associations
between the temperamental traits and the narrative emotional
expression. The Temperament Questionnaire was used: The FCB-TI
of Zawadzki & Strelau. A sample of 85 persons described three
emotional situations: love. hate, and anxiety. This study analyzes the
verbal form of expression by means of a written account of
emotions. The relationship between the narratives of love, hate and
anxiety and temperament characteristics were studied. Results
indicate that vigorousness (VI), perseverance (PE), sensory
sensitivity (SS), emotional reactivity (ER), endurance (EN) and
activeness (AC) have a significant impact on the emotional
expression in narratives. The temperamental traits are linked to the
form of emotional language. It means that temperament has an
impact on cognitive representations of emotions.
Abstract: In this paper, we propose a novel approach for image
segmentation via fuzzification of Rènyi Entropy of Generalized
Distributions (REGD). The fuzzy REGD is used to precisely measure
the structural information of image and to locate the optimal
threshold desired by segmentation. The proposed approach draws
upon the postulation that the optimal threshold concurs with
maximum information content of the distribution. The contributions
in the paper are as follow: Initially, the fuzzy REGD as a measure of
the spatial structure of image is introduced. Then, we propose an
efficient entropic segmentation approach using fuzzy REGD.
However the proposed approach belongs to entropic segmentation
approaches (i.e. these approaches are commonly applied to grayscale
images), it is adapted to be viable for segmenting color images.
Lastly, diverse experiments on real images that show the superior
performance of the proposed method are carried out.
Abstract: In the paper, the performance of quasi-synchronous
CDMA (QS-CDMA) system, which can allow an increased timing
error in synchronized access, is discussed. Average BER performance
of the system is analyzed in the condition of different access timing
error and different asynchronous users by simulation in AWGN
channel. The results show that QS-CDMA system is shown to have
great performance gain over the asynchronous system when access
timing error is within a few chips and asynchronous users is tolerable.
However, with access timing error increasing and asynchronous users
increasing, the performance of QS-CDMA will degrade. Also, we can
determine the number of tolerable asynchronous users for different
access timing error by simulation figures.
Abstract: South Africa is facing a crisis with not being able to produce enough graduates in the scarce skills areas to sustain economic growth. The crisis is fuelled by a school system that does not produce enough potential students with Mathematics, Accounting and Science. Since the introduction of the new school curriculum in 2008, there is no longer an option to take pure maths on a standard grade level. Instead, only two mathematical subjects are offered: pure maths (which is on par with higher grade maths) and mathematical literacy. It is compulsory to take one or the other. As a result, lees student finishes Grade 12 with pure mathematics every year. This national problem needs urgent attention if South Africa is to make any headway in critical skills development as mathematics is a gateway to scarce skills professions. Higher education institutions initiated several initiatives in an attempt to address the above, including preparatory courses, bridging programmes and extended curricula with foundation provisions. In view of the above, and government policy directives to broaden access in the scarce skills areas to increase student throughput, foundation provision was introduced for Commerce and Information Technology programmes at the Vaal Triangle Campus (VTC) of North-West University (NWU) in 2010. Students enrolling for extended programmes do not comply with the minimum prerequisites for the normal programmes. The question then arises as to whether these programmes have the intended impact? This paper reports the results of a two year longitudinal study, tracking the first year academic achievement of the two cohorts of enrolments since 2010. The results provide valuable insight into the structuring of an extended programme and its potential impact.
Abstract: Many supervised induction algorithms require discrete
data, even while real data often comes in a discrete
and continuous formats. Quality discretization of continuous
attributes is an important problem that has effects on speed,
accuracy and understandability of the induction models. Usually,
discretization and other types of statistical processes are applied
to subsets of the population as the entire population is practically
inaccessible. For this reason we argue that the discretization
performed on a sample of the population is only an estimate of
the entire population. Most of the existing discretization methods,
partition the attribute range into two or several intervals using
a single or a set of cut points. In this paper, we introduce a
technique by using resampling (such as bootstrap) to generate
a set of candidate discretization points and thus, improving the
discretization quality by providing a better estimation towards
the entire population. Thus, the goal of this paper is to observe
whether the resampling technique can lead to better discretization
points, which opens up a new paradigm to construction of
soft decision trees.
Abstract: There is a general feeling that Internet crime is an
advanced type of crime that has not yet infiltrated developing
countries like Uganda. The carefree nature of the Internet in which
anybody publishes anything at anytime poses a serious security threat
for any nation. Unfortunately, there are no formal records about this
type of crime for Uganda. Could this mean that it does not exist
there? The author conducted an independent research to ascertain
whether cyber crimes have affected people in Uganda and if so, to
discover where they are reported. This paper highlights the findings.
Abstract: The medical studies often require different methods
for parameters selection, as a second step of processing, after the
database-s designing and filling with information. One common
task is the selection of fields that act as risk factors using wellknown
methods, in order to find the most relevant risk factors and
to establish a possible hierarchy between them. Different methods
are available in this purpose, one of the most known being the
binary logistic regression. We will present the mathematical
principles of this method and a practical example of using it in the
analysis of the influence of 10 different psychiatric diagnostics
over 4 different types of offences (in a database made from 289
psychiatric patients involved in different types of offences).
Finally, we will make some observations about the relation
between the risk factors hierarchy established through binary
logistic regression and the individual risks, as well as the results of
Chi-squared test. We will show that the hierarchy built using the
binary logistic regression doesn-t agree with the direct order of risk
factors, even if it was naturally to assume this hypothesis as being
always true.