Abstract: An alarming emergence of multidrug-resistant strains
of the tuberculosis pathogen Mycobacterium tuberculosis and
continuing high worldwide incidence of tuberculosis has invigorated
the search for novel drug targets. The enzyme glutamate racemase
(MurI) in bacteria catalyzes the stereoconversion of L-glutamate to
D-glutamate which is a component of the peptidoglycan cell wall of
the bacterium. The inhibitors targeted against MurI from several
bacterial species have been patented and are advocated as promising
antibacterial agents. However there are none available against MurI
from Mycobacterium tuberculosis, due to the lack of its threedimensional
structure. This work accomplished two major objectives.
First, the tertiary structure of MtMurI was deduced computationally
through homology modeling using the templates from bacterial
homologues. It is speculated that like in other Gram-positive bacteria,
MtMurI exists as a dimer and many of the protein interactions at the
dimer interface are also conserved. Second, potent candidate
inhibitors against MtMurI were identified through docking against
already known inhibitors in other organisms.
Abstract: The prediction of Software quality during development life cycle of software project helps the development organization to make efficient use of available resource to produce the product of highest quality. “Whether a module is faulty or not" approach can be used to predict quality of a software module. There are numbers of software quality prediction models described in the literature based upon genetic algorithms, artificial neural network and other data mining algorithms. One of the promising aspects for quality prediction is based on clustering techniques. Most quality prediction models that are based on clustering techniques make use of K-means, Mixture-of-Guassians, Self-Organizing Map, Neural Gas and fuzzy K-means algorithm for prediction. In all these techniques a predefined structure is required that is number of neurons or clusters should be known before we start clustering process. But in case of Growing Neural Gas there is no need of predetermining the quantity of neurons and the topology of the structure to be used and it starts with a minimal neurons structure that is incremented during training until it reaches a maximum number user defined limits for clusters. Hence, in this work we have used Growing Neural Gas as underlying cluster algorithm that produces the initial set of labeled cluster from training data set and thereafter this set of clusters is used to predict the quality of test data set of software modules. The best testing results shows 80% accuracy in evaluating the quality of software modules. Hence, the proposed technique can be used by programmers in evaluating the quality of modules during software development.
Abstract: This article illustrates a model selection management approach for virtual prototypes in interactive simulations. In those numerical simulations, the virtual prototype and its environment are modelled as a multiagent system, where every entity (prototype,human, etc.) is modelled as an agent. In particular, virtual prototyp ingagents that provide mathematical models of mechanical behaviour inform of computational methods are considered. This work argues that selection of an appropriate model in a changing environment,supported by models? characteristics, can be managed by the deter-mination a priori of specific exploitation and performance measures of virtual prototype models. As different models exist to represent a single phenomenon, it is not always possible to select the best one under all possible circumstances of the environment. Instead the most appropriate shall be selecting according to the use case. The proposed approach consists in identifying relevant metrics or indicators for each group of models (e.g. entity models, global model), formulate their qualification, analyse the performance, and apply the qualification criteria. Then, a model can be selected based on the performance prediction obtained from its qualification. The authors hope that this approach will not only help to inform engineers and researchers about another approach for selecting virtual prototype models, but also assist virtual prototype engineers in the systematic or automatic model selection.
Abstract: The daily growing use of agents in software environments, because of many reasons such as independence and intelligence is not a secret anymore. One of such environments in which there is a prominent job for the agents would be emarketplaces in which a user is able to give those agents the responsibility of buying and selling, instead of searching the emarketplace himself. Making up a framework which has sufficient attention to the required roles and their relations, is the first step of achieving such e-markets. In this paper, we suggest a framework in order to establish such e-markets and we will continue investigating the roles such as seller or buyer and the relations in JADE environment in details.
Abstract: Design for Disassembly (DfD) aims to reuse the
structural components instead of demolition followed by recycling of
the demolition debris. This concept preserves the invested embodied
energy of materials, thus reducing inputs of new embodied energy
during materials reprocessing or remanufacturing. Both analytical and
experimental research on a proposed DfD beam-column connection
for use in residential apartments is currently investigated at the
National University of Singapore in collaboration with the Housing
and Development Board of Singapore. The present study reports on
the results of a numerical analysis of the proposed connection utilizing
finite element analysis. The numerical model was calibrated and
validated by comparison against experimental results. Results of a
parametric study will also be presented and discussed.
Abstract: This paper presents a time control liquids mixing
system in the tanks as an application of fuzzy time control discrete
model. The system is designed for a wide range of industrial
applications. The simulation design of control system has three
inputs: volume, viscosity, and selection of product, along with the
three external control adjustments for the system calibration or to
take over the control of the system autonomously in local or
distributed environment. There are four controlling elements: rotatory
motor, grinding motor, heating and cooling units, and valves
selection, each with time frame limit. The system consists of three
controlled variables measurement through its sensing mechanism for
feed back control. This design also facilitates the liquids mixing
system to grind certain materials in tanks and mix with fluids under
required temperature controlled environment to achieve certain
viscous level. Design of: fuzzifier, inference engine, rule base,
deffuzifiers, and discrete event control system, is discussed. Time
control fuzzy rules are formulated, applied and tested using
MATLAB simulation for the system.
Abstract: Installation of power compensation equipment in
some cases places additional buses into the system. Therefore, a total
number of power flow equations and voltage unknowns increase due
to additional locations of installed devices. In this circumstance, power flow calculation is more complicated. It may result in a
computational convergence problem. This paper presents a power flow calculation by using Newton-Raphson iterative method together
with the proposed load transfer technique. This concept is to eliminate additional buses by transferring installed loads at the new buses to existing two adjacent buses. Thus, the total number of power
flow equations is not changed. The overall computational speed is
expectedly shorter than that of solving the problem without applying the load transfer technique. A 15-bus test system is employed for test
to evaluate the effectiveness of the proposed load transfer technique. As a result, the total number of iteration required and execution time
is significantly reduced.
Abstract: Recently, as information industry and mobile
communication technology are developing, this study is conducted on
the new concept of intelligent structures and maintenance techniques
that applied wireless sensor network, USN (Ubiquitous Sensor
Network), to social infrastructures such as civil and architectural
structures on the basis of the concept of Ubiquitous Computing that
invisibly provides human life with computing, along with mutually
cooperating, compromising and connecting networks each other by
having computers within all objects around us.
Therefore, the purpose of this study is to investigate the capability
of wireless communication of sensor node embedded in reinforced
concrete structure with a basic experiment on an electric wave
permeability of sensor node by fabricating molding with variables of
concrete thickness and steel bars that are mostly used in constructing
structures to determine the feasibility of application to constructing
structures with USN.
At this time, with putting the pitches of steel bars, the thickness of
concrete placed, and the intensity of RF signal of a
transmitter-receiver as variables and when wireless communication
module was installed inside, the possible communication distance of
plain concrete and the possible communication distance by the pitches
of steel bars was measured in the horizontal and vertical direction
respectively. Besides, for the precise measurement of diminution of an
electric wave, the magnitude of an electric wave in the range of used
frequencies was measured by using Spectrum Analyzer. The
phenomenon of diminution of an electric wave was numerically
analyzed and the effect of the length of wavelength of frequencies was
analyzed by the properties of a frequency band area.
As a result of studying the feasibility of an application to
constructing structures with wireless sensor, in case of plain concrete,
it shows 45cm for the depth of permeability and in case of reinforced
concrete with the pitches of 5cm, it shows 37cm and 45cm for the
pitches of 15cm.
Abstract: The major aim of this paper is to investigate the opposition politics in Africa. The paper also examines the status and the role, the contributions and the weaknesses of opposition1 political parties in Africa, particularly in transitional democracies that emerged in the 1990s. In Africa, many of the opposition parties appear or become active only during an election, and disappear when the election is over. It is found out that most of the opposition parties in Africa are established around the personalities of individuals, lack internal democracy, suffer from inter-party and intra-party conflicts, have severe shortage of finance, and lack strong base and experience. Their weaknesses also include bad organization and weak connection with the popular constituencies. The paper concludes that most of the weaknesses of the African opposition parties emanate from the incumbents- hostile policies, which are mostly aimed at fragmenting and weakening the opposition groups.
Abstract: In this study, a new and fast algorithm for Ascending
Aorta (AscA) and Descending Aorta (DesA) segmentation is
presented using Computed Tomography Angiography images. This
process is quite important especially at the detection of aortic
plaques, aneurysms, calcification or stenosis. The applied method has
been carried out at four steps. At first step, lung segmentation is
achieved. At the second one, Mediastinum Region (MR) is detected
to use in the segmentation. At the third one, images have been
applied optimal threshold and components which are outside of the
MR were removed. Lastly, identifying and segmentation of AscA and
DesA have been carried out. The performance of the applied method
is found quite well for radiologists and it gives enough results to the
surgeries medically.
Abstract: Environment-assisted cracking (EAC) is one of the most serious causes of structural failure over a broad range of industrial applications including offshore structures. In EAC condition there is not a definite relation such as Paris equation in Linear Elastic Fracture Mechanics (LEFM). According to studying and searching a lot what the researchers said either a material has contact with hydrogen or any other corrosive environment, phenomenon of electrical and chemical reactions of material with its environment will be happened. In the literature, there are many different works to consider fatigue crack growing and solve it but they are experimental works. Thus, in this paper, authors have an aim to evaluate mathematically the pervious works in LEFM. Obviously, if an environment is more sour and corrosive, the changes of stress intensity factor is more and the calculation of stress intensity factor is difficult. A mathematical relation to deal with the stress intensity factor during the diffusion of sour environment especially hydrogen in a marine pipeline is presented. By using this relation having and some experimental relation an analytical formulation will be presented which enables the fatigue crack growth and critical crack length under cyclic loading to be predicted. In addition, we can calculate KSCC and stress intensity factor in the pipeline caused by EAC.
Abstract: Petrology and geochemical characteristics of granitic
rocks from South Sulawesi, especially from Polewaliand Masamba
area are presented in order to elucidate their origin of magma and
geodynamic setting. The granitic rocks in these areas are dominated by
granodiorite and granite in composition. Quartz, K-feldspar and
plagioclase occur as major phases with hornblende and biotite as
major ferromagnesian minerals. All of the samples were plotted in
calc-alkaline field, show metaluminous affinity and typical of I-type
granitic rock. Harker diagram indicates that granitic rocks experienced
fractional crystallization during magmatic evolution. Both groups
displayed an extreme enrichment of LILE, LREE and a slight negative
Eu anomaly which resemble upper continental crust affinity. They
were produced from partial melting of upper continental crust and
have close relationship of sources composition within a suite. The
geochemical characteristics explained the arc related subduction
environment which later give an evidence of continent-continent
collision between Australia-derived microcontinent and Sundalandto
form continental arc environment.
Abstract: The ultimate goal of this article is to develop a robust and accurate numerical method for solving hyperbolic conservation laws in one and two dimensions. A hybrid numerical method, coupling a cheap fourth order total variation diminishing (TVD) scheme [1] for smooth region and a Robust seventh-order weighted non-oscillatory (WENO) scheme [2] near discontinuities, is considered. High order multi-resolution analysis is used to detect the high gradients regions of the numerical solution in order to capture the shocks with the WENO scheme, while the smooth regions are computed with fourth order total variation diminishing (TVD). For time integration, we use the third order TVD Runge-Kutta scheme. The accuracy of the resulting hybrid high order scheme is comparable with these of WENO, but with significant decrease of the CPU cost. Numerical demonstrates that the proposed scheme is comparable to the high order WENO scheme and superior to the fourth order TVD scheme. Our scheme has the added advantage of simplicity and computational efficiency. Numerical tests are presented which show the robustness and effectiveness of the proposed scheme.
Abstract: In this study, we experiment on precise control outlet
temperature of water from the water cooler with hot-gas bypass
method based on PI control logic for machine tool. Recently, technical
trend for machine tools is focused on enhancement of speed and
accuracy. High speedy processing causes thermal and structural
deformation of objects from the machine tools. Water cooler has to be
applied to machine tools to reduce the thermal negative influence with
accurate temperature controlling system. The goal of this study is to
minimize temperature error in steady state. In addition, control period
of an electronic expansion valve were considered to increment of
lifetime of the machine tools and quality of product with a water
cooler.
Abstract: In this paper is study the possibility of successfully
implementing of hollow roller concept in order to minimize inertial
mass of the large bearings, with major results in diminution of the
material consumption, increasing of power efficiency (in wind power
station area), increasing of the durability and life duration of the large
bearings systems, noise reduction in working, resistance to
vibrations, an important diminution of losses by abrasion and
reduction of the working temperature. In this purpose was developed
an original solution through which are reduced mass, inertial forces
and moments of large bearings by using of hollow rollers. The
research was made by using the method of finite element analysis
applied on software type Solidworks - Nastran. Also, is study the
possibility of rapidly changing the manufacturing system of solid and
hollow cylindrical rollers.
Abstract: For this study, this researcher conducted a precision
network adjustment with QOCA, the precision network adjustment
software developed by Jet Propulsion Laboratory, to perform an
integrated network adjustment on the Unified Control Points managed
by the National Geographic Information Institute. Towards this end,
275 Unified Control Points observed in 2008 were selected before a
network adjustment is performed on those 275 Unified Control Points.
The RMSE on the discrepancies of coordinates as compared to the
results of GLOBK was ±6.07mm along the N axis, ±2.68mm along the
E axis and ±6.49mm along the U axis.
Abstract: In order to provide and maintain effective pedagogy for the burgeoning virtual reality community, it is vital to have trained faculty in the institutions of higher education who will teach these courses and be able to make full use of their academic knowledge and expertise. As the number of online courses continues to grow, there is a need for these institutions to establish mentoring programs that will support the novice online instructor. The environment in which this takes place and the factors that ensure its success are critical to the adoption of the new instructional delivery format taught by both seasoned educators and adjunct instructors. Effective one-on-one mentoring promotes a professional, compassionate and collegial faculty who will provide a consistent and rigorous academic program for students online.
Abstract: Nowadays, OCR systems have got several
applications and are increasingly employed in daily life. Much
research has been done regarding the identification of Latin,
Japanese, and Chinese characters. However, very little investigation
has been performed regarding Farsi/Arabic characters recognition.
Probably the reason is difficulty and complexity of those characters
identification compared to the others and limitation of IT activities in
Farsi and Arabic speaking countries. In this paper, a technique has
been employed to identify isolated Farsi/Arabic characters. A chain
code based algorithm along with other significant peculiarities such
as number and location of dots and auxiliary parts, and the number of
holes existing in the isolated character has been used in this study to
identify Farsi/Arabic characters. Experimental results show the
relatively high accuracy of the method developed when it is tested on
several standard Farsi fonts.
Abstract: Over a million tonnes of cigarette butts (CBs) are produced worldwide annually. These CBs accumulate in the environment due to the poor biodegradability of the cellulose acetate filters and pose a serious environmental risk. This paper presents some of the results from a continuing study on recycling CBs into fired clay bricks. Properties including compressive strength, flexural strength, density, water absorption and thermal conductivity of fired clay bricks are reported and discussed. Furthermore, leaching of heavy metals from the manufactured clay bricks was tested. The results show that the density of fired bricks was reduced by about 8 – 30 %, depending on the percentage of CBs incorporated into the raw materials. The compressive strength of bricks tested was 12.57, 5.22 and 3.00 MPa for 2.5, 5.0 and 10 % CB content respectively. Water absorption and initial rate of absorption values increased as density, and hence porosity, of bricks decreased with increasing CB volume. The leaching test results revealed trace amounts of heavy metals.
Abstract: Enhancement of the performance of a reverse osmosis
(RO) unit through periodic control is studied. The periodic control
manipulates the feed pressure and flow rate of the RO unit. To ensure
the periodic behavior of the inputs, the manipulated variables (MV)
are transformed into the form of sinusoidal functions. In this case, the
amplitude and period of the sinusoidal functions become the
surrogate MV and are thus regulated via nonlinear model predictive
control algorithm. The simulation results indicated that the control
system can generate cyclic inputs necessary to enhance the closedloop
performance in the sense of increasing the permeate production
and lowering the salt concentration. The proposed control system can
attain its objective with arbitrary set point for the controlled outputs.
Successful results were also obtained in the presence of modeling
errors.