Abstract: Heterogeneous catalysis is vital for a number of
chemical, refinery and pollution control processes. The use of
catalyst pellets of hollow cylindrical shape provide several distinct
advantages over other common shapes, and can therefore help to
enhance conversion levels in reactors. A better utilization of the
catalytic material is probably most notable of these features due to
the absence of the pellet core, which helps to significantly lower the
effect of the internal transport resistance. This is reflected in the
enhancement of the effectiveness factor. For the case of the first order
irreversible kinetics, a substantial increase in the effectiveness factor
can be obtained by varying shape parameters. Important shape
parameters of a finite hollow cylinder are the ratio of the inside to the
outside radii (κ) and the height to the diameter ratio (γ). A high value
of κ the generally helps to enhance the effectiveness factor. On the
other hand, lower values of the effectiveness factors are obtained
when the dimension of the height and the diameter are comparable.
Thus, the departure of parameter γ from the unity favors higher
effectiveness factor. Since a higher effectiveness factor is a measure
of a greater utilization of the catalytic material, higher conversion
levels can be achieved using the hollow cylindrical pellets possessing
optimized shape parameters.
Abstract: The theoretical prediction of the acoustical
polarization effects in the heterogeneous composites, made of thick
elastic solids with thin nematic films, is presented. The numericalanalytical
solution to the problem of the different wave propagation
exhibits some new physical effects in the low frequency domain: the
appearance of the critical frequency and the existence of the narrow
transition zone where the wave rapidly changes its speed. The
associated wave attenuation is highly perturbed in this zone. We also
show the possible appearance of the critical frequencies where the
attenuation changes the sign. The numerical results of parametrical
analysis are presented and discussed.
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: Wrist pulse analysis for identification of health status
is found in Ancient Indian as well as Chinese literature. The preprocessing
of wrist pulse is necessary to remove outlier pulses and
fluctuations prior to the analysis of pulse pressure signal. This paper
discusses the identification of irregular pulses present in the pulse
series and intricacies associated with the extraction of time domain
pulse features. An approach of Dynamic Time Warping (DTW) has
been utilized for the identification of outlier pulses in the wrist pulse
series. The ambiguity present in the identification of pulse features is
resolved with the help of first derivative of Ensemble Average of
wrist pulse series. An algorithm for detecting tidal and dicrotic notch
in individual wrist pulse segment is proposed.
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: The growing problem of youth unemployment in
Egypt after the 25th January Revolution has directed the attention of
some human resource experts towards considering remote
employment as a partial remedy for the unemployed youth instead of
the unavailable traditional jobs, a trend which will also help with the
congested offices and unsolved traffic problem in Cairo and spread
a flexible work culture, but despite of that, the main issue remains
unresolved for these organizations to deal with the system challenges.
In the past few years, in developed countries, there has been a
growing trend for many companies to shift to remote employment
instead of the traditional office employment for many reasons: due to
the growing technological advances that helped some employees do
their work from home on a part time basis, the need for achieving an
employee-s work balance in the middle of unbalanced complicated
life, top management focus on employee-s productivity rather their
time spent at work. The objective of this paper is to study and analyze
the advantages and challenges that Egypt-s labor force will be facing
in their implementation of remote or virtual employment in both
government and private organizations after the 25th January
revolution. Therefore, the research question will be: What are the
advantages and different challenges that Egyptian organizations
might face in their implementation for remote employment system
and how can they manage these challenges for the system to work
effectively? The study is divided into six main parts: the introduction,
objective and importance of the study, research problem,
methodology, experience of some countries that implemented remote
employment, advantages and challenges of implementing remote
employment in Egypt and then the conclusion which discuses the
results and recommendations of the study.
Abstract: Texture classification is a trendy and a catchy
technology in the field of texture analysis. Textures, the repeated
patterns, have different frequency components along different
orientations. Our work is based on Texture Classification and its
applications. It finds its applications in various fields like Medical
Image Classification, Computer Vision, Remote Sensing,
Agricultural Field, and Textile Industry. Weed control has a major
effect on agriculture. A large amount of herbicide has been used for
controlling weeds in agriculture fields, lawns, golf courses, sport
fields, etc. Random spraying of herbicides does not meet the exact
requirement of the field. Certain areas in field have more weed
patches than estimated. So, we need a visual system that can
discriminate weeds from the field image which will reduce or even
eliminate the amount of herbicide used. This would allow farmers to
not use any herbicides or only apply them where they are needed. A
machine vision precision automated weed control system could
reduce the usage of chemicals in crop fields. In this paper, an
intelligent system for automatic weeding strategy Multi Resolution
Combined Statistical & spatial Frequency is used to discriminate the
weeds from the crops and to classify them as narrow, little and broad
weeds.
Abstract: Renewable natural fibres such as oil palm, flax, and
pineapple leaf can be utilized to obtain new high performance
polymer materials. The reuse of waste natural fibres as reinforcement
for polymer is a sustainable option to the environment. However, due
to its high hydroxyl content of cellulose, natural fibres are
susceptible to absorb water that affects the composite mechanical
properties adversely. Research found that Nano materials such as
Nano Silica Carbide (n-SiC) and Nano Clay can be added into the
polymer composite to overcome this problem by enhancing its
mechanical properties in wet condition. The addition of Nano
material improves the tensile and wear properties, flexural stressstrain
behaviour, fracture toughness, and fracture strength of polymer
natural composites in wet and dry conditions.
Abstract: The use of wind energy for electricity generation is
growing rapidly across the world and in Portugal. However, the
geographical characteristics of the country along with the average
wind regime and with the environmental restrictions imposed to these
projects create limitations to the exploit of the onshore wind
resource. The best onshore wind spots are already committed and the
possibility of offshore wind farms in the Portuguese cost is now
being considered. This paper aims to make a contribution to the
evaluation of offshore wind power projects in Portugal. The technical
restrictions are addressed and the strategic, environmental and
financial interest of the project is analysed from the private company
and public points of view. The results suggest that additional support
schemes are required to ensure private investors interest for these
projects. Assuming an approach of direct substitution of energy
sources for electricity generation, the avoided CO2 equivalent
emissions for an offshore wind power project were quantified. Based
on the conclusions, future research is proposed to address the
environmental and social impacts of these projects.
Abstract: In this paper, we first give the representation of the general solution of the following inverse eigenvalue problem (IEP): Given X ∈ Rn×p and a diagonal matrix Λ ∈ Rp×p, find nontrivial real-valued symmetric arrow-head matrices A and B such that AXΛ = BX. We then consider an optimal approximation problem: Given real-valued symmetric arrow-head matrices A, ˜ B˜ ∈ Rn×n, find (A, ˆ Bˆ) ∈ SE such that Aˆ − A˜2 + Bˆ − B˜2 = min(A,B)∈SE (A−A˜2 +B −B˜2), where SE is the solution set of IEP. We show that the optimal approximation solution (A, ˆ Bˆ) is unique and derive an explicit formula for it.
Abstract: This study utilizes the panel vector error correction
model (PVECM) to examine the relationship among corruption,
economic growth, and income inequality experienced within ten Asian
countries over the 1995 to 2010 period. According to the empirical
results, we do not support the common perception that corruption
decreases economic growth. On the contrary, we found that corruption
increases economic growth. Meanwhile, an increase in economic
growth will cause an increase in income inequality, although the effect
is insignificant. Similarly, an increase in income inequality will cause
an increase in economic growth but a decrease in corruption, although
the effect is also insignificant.
Abstract: Flow-shop scheduling problem (FSP) deals with the
scheduling of a set of jobs that visit a set of machines in the same
order. The FSP is NP-hard, which means that an efficient algorithm
for solving the problem to optimality is unavailable. To meet the
requirements on time and to minimize the make-span performance of
large permutation flow-shop scheduling problems in which there are
sequence dependent setup times on each machine, this paper
develops one hybrid genetic algorithms (HGA). Proposed HGA
apply a modified approach to generate population of initial
chromosomes and also use an improved heuristic called the iterated
swap procedure to improve initial solutions. Also the author uses
three genetic operators to make good new offspring. The results are
compared to some recently developed heuristics and computational
experimental results show that the proposed HGA performs very
competitively with respect to accuracy and efficiency of solution.
Abstract: This study aims to assess the vulnerability and risk of
the coastal areas of Taijiang to abnormal oceanographic phenomena.
In addition, this study aims to investigate and collect data regarding
the disaster losses, land utilization, and other social, economic, and
environmental issues in these coastal areas to construct a coastal
vulnerability and risk map based on the obtained climate-change risk
assessment results. Considering the indexes of the three coastal
vulnerability dimensions, namely, man-made facilities, environmental
geography, and social economy, this study adopted the equal
weighting process and Analytic Hierarchy Process to analyze the
vulnerability of these coastal areas to disasters caused by climatic
changes. Among the areas with high coastal vulnerability to climatic
changes, three towns had the highest coastal vulnerability and four had
the highest relative vulnerability. Areas with lower disaster risks were
found to be increasingly vulnerable to disasters caused by climatic
changes as time progresses.
Abstract: Technical laboratories are typically considered as
highly hazardous places in the polytechnic institution when
addressing the problems of high incidences and fatality rates. In
conjunction with several topics covered in the technical curricular,
safety and health precaution should be highlighted in order to
connect to few key ideas of being safe. Therefore the assessment of
safety awareness in terms of safety and health about hazardous and
risks at laboratories is needed and has to be incorporated with
technical education and other training programmes. The purpose of
this study was to determine the efficacy of technical laboratory safety
in one of the polytechnics in northern region. The study examined
three related issues that were; the availability of safety material and
equipment, safety practice adopted by technical teachers and
administrator-s safety attitudes in enforcing safety to the students. A
model of efficacy technical laboratory was developed to test the
linear relationship between existing safety material and equipment,
teachers- safety practice and administrators- attitude in enforcing
safety and to identify which of technical laboratory safety issues was
the most pertinent factor to realize safety in technical laboratory.
This was done by analyzing survey-based data sets particularly those
obtained from samples of 210 students in the polytechnic. The
Pearson Correlation was used to measure the association between the
variables and to test the research hypotheses. The result of the study
has found that there was a significant correlation between existing
safety material and equipment, safety practice adopted by teacher
and administrator-s attitude. There was also a significant relationship
between technical laboratory safety and safety practice adopted by
teacher and between technical laboratory safety and administrator
attitude. Hence, safety practice adopted by teacher and administrator
attitude is vital in realizing technical laboratory safety.
Abstract: In the current study we present a system that is
capable to deliver proxy based differentiated service. It will help the
carrier service node to sell a prepaid service to clients and limit the
use to a particular mobile device or devices for a certain time. The
system includes software and hardware architecture for a mobile
device with moderate computational power, and a secure protocol for
communication between it and its carrier service node. On the
carrier service node a proxy runs on a centralized server to be
capable of implementing cryptographic algorithms, while the mobile
device contains a simple embedded processor capable of executing
simple algorithms. One prerequisite is needed for the system to run
efficiently that is a presence of Global Trusted Verification Authority
(GTVA) which is equivalent to certifying authority in IP networks.
This system appears to be of great interest for many commercial
transactions, business to business electronic and mobile commerce,
and military applications.
Abstract: In this paper, many techniques for blind identification of moving average (MA) process are presented. These methods utilize third- and fourth-order cumulants of the noisy observations of the system output. The system is driven by an independent and identically distributed (i.i.d) non-Gaussian sequence that is not observed. Two nonlinear optimization algorithms, namely the Gradient Descent and the Gauss-Newton algorithms are exposed. An algorithm based on the joint-diagonalization of the fourth-order cumulant matrices (FOSI) is also considered, as well as an improved version of the classical C(q, 0, k) algorithm based on the choice of the Best 1-D Slice of fourth-order cumulants. To illustrate the effectiveness of our methods, various simulation examples are presented.
Abstract: This paper proposes a modeling method of the laws controlling manufacturing systems with temporal and non temporal constraints. A methodology of robust control construction generating the margins of passive and active robustness is being elaborated. Indeed, two paramount models are presented in this paper. The first utilizes the P-time Petri Nets which is used to manage the flow type disturbances. The second, the quality model, exploits the Intervals Constrained Petri Nets (ICPN) tool which allows the system to preserve its quality specificities. The redundancy of the robustness of the elementary parameters between passive and active is also used. The final model built allows the correlation of temporal and non temporal criteria by putting two paramount models in interaction. To do so, a set of definitions and theorems are employed and affirmed by applicator examples.
Abstract: The National Blood Center, Thai Red Cross Society is
responsible for providing blood to hospitals all over the country.
When any hospital needs blood, it will have to send the vehicle to
pick up at the NBC. There are a lot of vehicles to pick up blood at the
NBC every day. Each vehicle is usually empty for inbound trip and a
little loaded for outbound. The NBC realized such waste or loss and
there have been the third party offered to distribute blood and charge
for fee. This paper proposes to apply the vehicle routing problem
(VRP) for estimating the fair price. The idea is tested with the real
data during seven-day period of 6 – 12 July 2010 to estimate the fair
price for transporting blood in Bangkok Metropolitan Region.
Abstract: The running logs of a process hold valuable
information about its executed activity behavior and generated activity
logic structure. Theses informative logs can be extracted, analyzed and
utilized to improve the efficiencies of the process's execution and
conduction. One of the techniques used to accomplish the process
improvement is called as process mining. To mine similar processes is
such an improvement mission in process mining. Rather than directly
mining similar processes using a single comparing coefficient or a
complicate fitness function, this paper presents a simplified heuristic
process mining algorithm with two similarity comparisons that are
able to relatively conform the activity logic sequences (traces) of
mining processes with those of a normalized (regularized) one. The
relative process conformance is to find which of the mining processes
match the required activity sequences and relationships, further for
necessary and sufficient applications of the mined processes to process
improvements. One similarity presented is defined by the relationships
in terms of the number of similar activity sequences existing in
different processes; another similarity expresses the degree of the
similar (identical) activity sequences among the conforming processes.
Since these two similarities are with respect to certain typical behavior
(activity sequences) occurred in an entire process, the common
problems, such as the inappropriateness of an absolute comparison and
the incapability of an intrinsic information elicitation, which are often
appeared in other process conforming techniques, can be solved by the
relative process comparison presented in this paper. To demonstrate
the potentiality of the proposed algorithm, a numerical example is
illustrated.