Abstract: Response surface methodology (RSM) is a very
efficient tool to provide a good practical insight into developing new
process and optimizing them. This methodology could help
engineers to raise a mathematical model to represent the behavior of
system as a convincing function of process parameters.
Through this paper the sequential nature of the RSM surveyed for process
engineers and its relationship to design of experiments (DOE), regression
analysis and robust design reviewed. The proposed four-step procedure in
two different phases could help system analyst to resolve the parameter
design problem involving responses. In order to check accuracy of the
designed model, residual analysis and prediction error sum of squares
(PRESS) described.
It is believed that the proposed procedure in this study can resolve a
complex parameter design problem with one or more responses. It can be
applied to those areas where there are large data sets and a number of
responses are to be optimized simultaneously. In addition, the proposed
procedure is relatively simple and can be implemented easily by using
ready-made standard statistical packages.
Abstract: Earth reinforcing techniques have become useful and economical to solve problems related to difficult grounds and provide satisfactory foundation performance. In this context, this paper uses radial basis function neural network (RBFNN) for predicting the bearing pressure of strip footing on reinforced granular bed overlying weak soil. The inputs for the neural network models included plate width, thickness of granular bed and number of layers of reinforcements, settlement ratio, water content, dry density, cohesion and angle of friction. The results indicated that RBFNN model exhibited more than 84 % prediction accuracy, thereby demonstrating its application in a geotechnical problem.
Abstract: This paper presents a text clustering system developed based on a k-means type subspace clustering algorithm to cluster large, high dimensional and sparse text data. In this algorithm, a new step is added in the k-means clustering process to automatically calculate the weights of keywords in each cluster so that the important words of a cluster can be identified by the weight values. For understanding and interpretation of clustering results, a few keywords that can best represent the semantic topic are extracted from each cluster. Two methods are used to extract the representative words. The candidate words are first selected according to their weights calculated by our new algorithm. Then, the candidates are fed to the WordNet to identify the set of noun words and consolidate the synonymy and hyponymy words. Experimental results have shown that the clustering algorithm is superior to the other subspace clustering algorithms, such as PROCLUS and HARP and kmeans type algorithm, e.g., Bisecting-KMeans. Furthermore, the word extraction method is effective in selection of the words to represent the topics of the clusters.
Abstract: Segmentation and quantification of stenosis is an
important task in assessing coronary artery disease. One of the main
challenges is measuring the real diameter of curved vessels.
Moreover, uncertainty in segmentation of different tissues in the
narrow vessel is an important issue that affects accuracy. This paper
proposes an algorithm to extract coronary arteries and measure the
degree of stenosis. Markovian fuzzy clustering method is applied to
model uncertainty arises from partial volume effect problem. The
algorithm employs: segmentation, centreline extraction, estimation of
orthogonal plane to centreline, measurement of the degree of
stenosis. To evaluate the accuracy and reproducibility, the approach
has been applied to a vascular phantom and the results are compared
with real diameter. The results of 10 patient datasets have been
visually judged by a qualified radiologist. The results reveal the
superiority of the proposed method compared to the Conventional
thresholding Method (CTM) on both datasets.
Abstract: Oxygen transfer, the process by which oxygen is
transferred from the gaseous to liquid phase, is a vital part of the
waste water treatment process. Because of low solubility of
oxygen and consequent low rate of oxygen transfer, sufficient
oxygen to meet the requirement of aerobic waste does not enter
through normal surface air water interface. Many theories have
come up in explaining the mechanism of gas transfer and
absorption of non-reacting gases in a liquid, of out of which, Two
film theory is important. An exiting mathematical model
determines approximate value of Overall Gas Transfer coefficient.
The Overall Gas Transfer coefficient, in case of Penetration theory,
is 1.13 time more than that obtained in case of Two film theory.
The difference is due to the difference in assumptions in the two
theories.
The paper aims at development of mathematical model which
determines the value of Overall Gas Transfer coefficient with
greater accuracy than the existing model.
Abstract: An experiment was conducted using two aeration
methods (water-into-air and air-into-water) and followed by filtration
processes using manganese greensand material. The properties of
groundwater such as pH, dissolved oxygen, turbidity and heavy metal
concentration (iron and manganese) will be assessed. The objectives
of this study are i) to determine the effective aeration method and ii)
to assess the effectiveness of manganese greensand as filter media in
removing iron and manganese concentration in groundwater. Results
showed that final pH for all samples after treatment are in range from
7.40 and 8.40. Both aeration methods increased the dissolved oxygen
content. Final turbidity for groundwater samples are between 3 NTU
to 29 NTU. Only three out of eight samples achieved iron
concentration of 0.3mg/L and less and all samples reach manganese
concentration of 0.1mg/L and less. Air-into-water aeration method
gives higher percentage of iron and manganese removal compare to
water-into-air method.
Abstract: An attempt was made for availability of wastewater reuse/reclamation for irrigation purposes using phytoremediation “the low cost and less technology", using six local aquatic macrophytes “e.g. T. angustifolia, B. maritimus, Ph. australis, A. donax, A. plantago-aquatica and M. longifolia (Linn)" as biological waste purifiers. Outdoor experiments/designs were conducted from May 03, 2007 till October 15, 2008, close to one of the main sewage channels of Sulaimani City/Iraq*. All processes were mainly based on conventional wastewater treatment processes, besides two further modifications were tested, the first was sand filtration pots, implanted by individual species of experimental macrophytes and the second was constructed wetlands implanted by experimental macrophytes all together. Untreated and treated wastewater samples were analyzed for their key physico-chemical properties (only heavy metals Fe, Mn, Zn and Cu with particular reference to removal efficiency by experimental macrophytes are highlighted in this paper). On the other hand, vertical contents of heavy metals were also evaluated from both pots and the cells of constructed wetland. After 135 days, macrophytes were harvested and heavy metals were analyzed in their biomass (roots/shoots) for removal efficiency assessment (i.e. uptake/ bioaccumulation rate). Results showed that; removal efficiency of all studied heavy metals was much higher in T. angustifolia followed by Ph. Australis, B. maritimus and A. donax in triple experiment sand pots. Constructed wetland experiments have revealed that; the more replicated constructed wetland cells the highest heavy metal removal efficiency was indicated.
Abstract: Quality evaluation of an image is an important task in image processing applications. In case of image compression, quality of decompressed image is also the criterion for evaluation of given coding scheme. In the process of compression -decompression various artifacts such as blocking artifacts, blur artifact, ringing or edge artifact are observed. However quantification of these artifacts is a difficult task. We propose here novel method to quantify blur and ringing artifact in an image.
Abstract: In this paper, the concepts of dichotomous logistic
regression (DLR) with leave-one-out (L-O-O) were discussed. To
illustrate this, the L-O-O was run to determine the importance of the
simulation conditions for robust test of spread procedures with good
Type I error rates. The resultant model was then evaluated. The
discussions included 1) assessment of the accuracy of the model, and
2) parameter estimates. These were presented and illustrated by
modeling the relationship between the dichotomous dependent
variable (Type I error rates) with a set of independent variables (the
simulation conditions). The base SAS software containing PROC
LOGISTIC and DATA step functions can be making used to do the
DLR analysis.
Abstract: Numerical studies have been carried out using a
validated two-dimensional RNG k-epsilon turbulence model for the
design optimization of a thrust vector control system using shock
induced supersonic secondary jet. Parametric analytical studies have
been carried out with various secondary jets at different divergent
locations, jet interaction angles, jet pressures. The results from the
parametric studies of the case on hand reveal that the primary nozzle
with a small divergence angle, downstream injections with a distance
of 2.5 times the primary nozzle throat diameter from the primary
nozzle throat location warrant higher efficiency over a certain range
of jet pressures and jet angles. We observed that the supersonic
secondary jet opposing the core flow with jets interaction angle of
40o to the axis far downstream of the nozzle throat facilitates better
thrust vectoring than the secondary jet with same direction as that of
core flow with various interaction angles. We concluded that fixing
of the supersonic secondary jet nozzle pointing towards the throat
direction with suitable angle at a distance 2 to 4 times of the primary
nozzle throat diameter, as the case may be, from the primary nozzle
throat location could facilitate better thrust vectoring for the
supersonic aerospace vehicles.
Abstract: Since hyaluronic acid (HA) receptor such as CD44 is
over-expressed at sites of cancer cells, HA can be used as a targeting
vehicles for anti-cancer drugs. The aim of this study is to synthesize
block copolymer composed of hyaluronic acid and
poly(ε-caprolactone) (HAPCL) and to fabricate polymeric micelles for
anticancer drug targeting against CD44 receptor of tumor cells.
Chemical composition of HAPCL was confirmed using 1H NMR
spectroscopy. Doxorubicin (DOX) was incorporated into polymeric
micelles of HAPCL. The diameters of HAPHS polymeric micelles
were changed around 80nm and have spherical shapes. Targeting
potential was investigated using CD44-overexpressing. When
DOX-incorporated polymeric micelles was added to KB cells, they
revealed strong red fluorescence color while blocking of CD44
receptor by pretreatment of free HA resulted in reduced intensity,
indicating that HAPCL polymeric micelles have targetability against
CD44 receptor.
Abstract: Mobile Ad hoc networks (MANETs) are collections
of wireless mobile nodes dynamically reconfiguring and collectively
forming a temporary network. These types of networks assume
existence of no fixed infrastructure and are often useful in battle-field
tactical operations or emergency search-and-rescue type of
operations where fixed infrastructure is neither feasible nor practical.
They also find use in ad hoc conferences, campus networks and
commercial recreational applications carrying multimedia traffic. All
of the above applications of MANETs require guaranteed levels of
performance as experienced by the end-user. This paper focuses on
key challenges in provisioning predetermined levels of such Quality
of Service (QoS). It also identifies functional areas where QoS
models are currently defined and used. Evolving functional areas
where performance and QoS provisioning may be applied are also
identified and some suggestions are provided for further research in
this area. Although each of the above functional areas have been
discussed separately in recent research studies, since these QoS
functional areas are highly correlated and interdependent, a
comprehensive and comparative analysis of these areas and their
interrelationships is desired. In this paper we have attempted to
provide such an overview.
Abstract: Selective harmonic elimination-pulse width modulation techniques offer a tight control of the harmonic spectrum of a given voltage waveform generated by a power electronic converter along with a low number of switching transitions. Traditional optimization methods suffer from various drawbacks, such as prolonged and tedious computational steps and convergence to local optima; thus, the more the number of harmonics to be eliminated, the larger the computational complexity and time. This paper presents a novel method for output voltage harmonic elimination and voltage control of PWM AC/AC voltage converters using the principle of hybrid Real-Coded Genetic Algorithm-Pattern Search (RGA-PS) method. RGA is the primary optimizer exploiting its global search capabilities, PS is then employed to fine tune the best solution provided by RGA in each evolution. The proposed method enables linear control of the fundamental component of the output voltage and complete elimination of its harmonic contents up to a specified order. Theoretical studies have been carried out to show the effectiveness and robustness of the proposed method of selective harmonic elimination. Theoretical results are validated through simulation studies using PSIM software package.
Abstract: A new generation product made from bamboo strips,
known as laminated bamboo, has gained importance. The objective
of this research was to experiment the effect of three factors on the
mechanical property of laminated bamboo. The interested factors for
experimental design were (A) four bamboo species, namely Bambusa
blumeana Schultes (Pai See Suk), Dendrocalamus asper Backer (Pai
Tong), Dendrocalamus hamiltonii Nees (Pai Hok) and
Dendrocalamus sericeus Munro (Pai Sang Mon), (B) two types of
glue adhesive, polyvinyl acetate emulsion (PVAC) fortified with
urea-formaldehyde (UF) and urea-formaldehyde (UF) to make
parallel-oriented bamboo strips laminates and (C) glue weight per
strip area, 150 g/m2 and 190 g/m2. Experimental results showed that
Dendrocalamus asper Backer (Pai Tong) and Dendrocalamus
sericeus Munro (Pai Sang Mon) were best used for manufacturing
due to their highest MOR and MOE. The amount of glue weight 150
g/m2 yielded higher MOR and MOE than the amount of glue weight
190 g/m2. At the conclusion, the laminated bamboo manufacturers
can benefit from this research in order to select right materials
according to strength, cost and accessibility.
Abstract: In this study, the effect of greywater irrigation on airwater interfacial area is investigated. Several soil column experiments were conducted for different greywater irrigation to develop the pressure-saturation curves. Surface tension was measured for different greywater concentration and fitted for Gibbs adsorption equation. Pressure-saturation curves show that the reduction of capillary rise stops when it reaches its critical micelle concentration (CMC). A simple theory is derived from pressure-saturation curves for calculating air-water interfacial area in porous medium during greywater irrigation by introducing a term 'hydraulic radius' for the pores. This term diminishes any effect of pore shapes on the air-water interfacial area. The air-water interfacial area was calculated using the pressure-saturation curves and found that it decreases with increasing moisture content. But no significant effect was observed on air-water interfacial area for different greywater irrigation. A maximum of 10% variation in interfacial area was observed at the residual saturation zone.
Abstract: Ad hoc networks are characterized by multi-hop
wireless connectivity and frequently changing network topology.
Forming security association among a group of nodes in ad-hoc
networks is more challenging than in conventional networks due to the
lack of central authority, i.e. fixed infrastructure. With that view in
mind, group key management plays an important building block of
any secure group communication. The main contribution of this paper
is a low complexity key management scheme that is suitable for fully
self-organized ad-hoc networks. The protocol is also password
authenticated, making it resilient against active attacks. Unlike other
existing key agreement protocols, ours make no assumption about the
structure of the underlying wireless network, making it suitable for
“truly ad-hoc" networks. Finally, we will analyze our protocol to show
the computation and communication burden on individual nodes for
key establishment.
Abstract: The process of laser absorption in the skin during
laser irradiation was a critical point in medical application
treatments. Delivery the correct amount of laser light is a critical
element in photodynamic therapy (PDT). More amounts of laser
light able to affect tissues in the skin and small amount not able to
enhance PDT procedure in skin. The knowledge of the skin tone
laser dependent distribution of 635 nm radiation and its penetration
depth in skin is a very important precondition for the investigation of
advantage laser induced effect in (PDT) in epidermis diseases
(psoriasis). The aim of this work was to estimate an optimum effect
of diode laser (635 nm) on the treatment of epidermis diseases in
different color skin. Furthermore, it is to improve safety of laser in
PDT in epidermis diseases treatment. Advanced system analytical
program (ASAP) which is a new approach in investigating the PDT,
dependent on optical properties of different skin color was used in
present work. A two layered Realistic Skin Model (RSM); stratum
corneum and epidermal with red laser (635 nm, 10 mW) were used
for irradiative transfer to study fluence and absorbance in different
penetration for various human skin colors. Several skin tones very
fair, fair, light, medium and dark are used to irradiative transfer. This
investigation involved the principles of laser tissue interaction when
the skin optically injected by a red laser diode. The results
demonstrated that the power characteristic of a laser diode (635 nm)
can affect the treatment of epidermal disease in various color skins.
Power absorption of the various human skins were recorded and
analyzed in order to find the influence of the melanin in PDT
treatment in epidermal disease. A two layered RSM show that the
change in penetration depth in epidermal layer of the color skin has a
larger effect on the distribution of absorbed laser in the skin; this is
due to the variation of the melanin concentration for each color.
Abstract: This paper details the application of a genetic
programming framework for induction of useful classification rules
from a database of income statements, balance sheets, and cash flow
statements for North American public companies. Potentially
interesting classification rules are discovered. Anomalies in the
discovery process merit further investigation of the application of
genetic programming to the dataset for the problem domain.
Abstract: This paper presents the application of an enhanced
Particle Swarm Optimization (EPSO) combined with Gaussian
Mutation (GM) for solving the Dynamic Economic Dispatch (DED)
problem considering the operating constraints of generators. The
EPSO consists of the standard PSO and a modified heuristic search
approaches. Namely, the ability of the traditional PSO is enhanced
by applying the modified heuristic search approach to prevent the
solutions from violating the constraints. In addition, Gaussian
Mutation is aimed at increasing the diversity of global search, whilst
it also prevents being trapped in suboptimal points during search. To
illustrate its efficiency and effectiveness, the developed EPSO-GM
approach is tested on the 3-unit and 10-unit 24-hour systems
considering valve-point effect. From the experimental results, it can
be concluded that the proposed EPSO-GM provides, the accurate
solution, the efficiency, and the feature of robust computation
compared with other algorithms under consideration.
Abstract: To extract the important physiological factors related to
diabetes from an oral glucose tolerance test (OGTT) by mathematical
modeling, highly informative but convenient protocols are required.
Current models require a large number of samples and extended
period of testing, which is not practical for daily use. The purpose
of this study is to make model assessments possible even from a
reduced number of samples taken over a relatively short period.
For this purpose, test values were extrapolated using a support
vector machine. A good correlation was found between reference and
extrapolated values in evaluated 741 OGTTs. This result indicates
that a reduction in the number of clinical test is possible through a
computational approach.