Abstract: In the present work, the effective moisture diffusivity
and activation energy were calculated using an infinite series solution
of Fick-s diffusion equation. The results showed that increasing
drying temperature accelerated the drying process. All drying
experiments had only falling rate period. The average effective
moisture diffusivity values varied from 2.807x10-10 to 6.977x10-10m2
s_1 over the temperature and velocity range. The temperature
dependence of the effective moisture diffusivity for the thin layer
drying of the ginger slices was satisfactorily described by an
Arrhenius-type relationship with activation energy values of 19.313-
22.722 kJ.mol-1 within 40–70 °C and 0.8-3 ms-1 temperature range.
Abstract: Malaria is transmitted to the human by biting of
infected Anopheles mosquitoes. This disease is a serious, acute and
chronic relapsing infection to humans. Fever, nausea, vomiting, back
pain, increased sweating anemia and splenomegaly (enlargement of
the spleen) are the symptoms of the patients who infected with this
disease. It is caused by the multiplication of protozoa parasite of the
genus Plasmodium. Plasmodium falciparum, Plasmodium vivax,
Plasmodium malariae and Plasmodium ovale are the four types of
Plasmodium malaria. A mathematical model for the transmission of
Plasmodium Malaria is developed in which the human and vector
population are divided into two classes, the susceptible and the
infectious classes. In this paper, we formulate the dynamical model
of Plasmodium falciparum and Plasmodium vivax malaria. The
standard dynamical analysis is used for analyzing the behavior for
the transmission of this disease. The Threshold condition is found
and numerical results are shown to confirm the analytical results.
Abstract: The simulation of external aerodynamics is one of the most challenging and important automotive CFD applications. With the rapid developments of digital computers, CFD is used as a practical tool in modern fluid dynamics research. It integrates fluid mechanics disciplines, mathematics and computer science. In this study, two different types of simulations were made, one for the flow around a simplified high speed passenger car with a rear-spoiler and the other for the flow without a rear-spoiler. The standard k-ε model is selected to numerically simulate the external flow field of the simplified Camry model with or without a rear-spoiler. Through an analysis of the simulation results, a new rear spoiler is designed and it shows a mild reduction of the vehicle aerodynamics drag. This leads to less vehicle fuel consumption on the road.
Abstract: In this paper, by using Mawhin-s continuation theorem of coincidence degree and a method based on delay differential inequality, some sufficient conditions are obtained for the existence and global exponential stability of periodic solutions of cellular neural networks with distributed delays and impulses on time scales. The results of this paper generalized previously known results.
Abstract: The process of wafer fabrication is arguably the most
technologically complex and capital intensive stage in semiconductor
manufacturing. This large-scale discrete-event process is highly reentrant,
and involves hundreds of machines, restrictions, and
processing steps. Therefore, production control of wafer fabrication
facilities (fab), specifically scheduling, is one of the most challenging
problems that this industry faces. Dispatching rules have been
extensively applied to the scheduling problems in semiconductor
manufacturing. Moreover, lot release policies are commonly used in
this manufacturing setting to further improve the performance of such
systems and reduce its inherent variability. In this work, simulation is
used in the scheduling of re-entrant flow shop manufacturing systems
with an application in semiconductor wafer fabrication; where, a
simulation model has been developed for the Intel Five-Machine Six
Step Mini-Fab using the ExtendTM simulation environment. The
Mini-Fab has been selected as it captures the challenges involved in
scheduling the highly re-entrant semiconductor manufacturing lines.
A number of scenarios have been developed and have been used to
evaluate the effect of different dispatching rules and lot release
policies on the selected performance measures. Results of simulation
showed that the performance of the Mini-Fab can be drastically
improved using a combination of dispatching rules and lot release
policy.
Abstract: There are reports of gas and oil wells fire due to different accidents. Many different methods are used for fire fighting in gas and oil industry. Traditional fire extinguishing techniques are mostly faced with many problems and are usually time consuming and needs lots of equipments. Besides, they cause damages to facilities, and create health and environmental problems. This article proposes innovative approach in fire extinguishing techniques in oil and gas industry, especially applicable for burning oil wells located offshore. Fire extinguishment employing a turbojet is a novel approach which can help to extinguishment the fire in short period of time. Divergent and convergent turbojets modeled in laboratory scale along with a high pressure flame were used. Different experiments were conducted to determine the relationship between output discharges of trumpet and oil wells. The results were corrected and the relationship between dimensionless parameters of flame and fire extinguishment distances and also the output discharge of turbojet and oil wells in specified distances are demonstrated by specific curves.
Abstract: In this paper we propose a new approach for flexible document categorization according to the document type or genre instead of topic. Our approach implements two homogenous classifiers: contextual classifier and logical classifier. The contextual classifier is based on the document URL, whereas, the logical classifier use the logical structure of the document to perform the categorization. The final categorization is obtained by combining contextual and logical categorizations. In our approach, each document is assigned to all predefined categories with different membership degrees. Our experiments demonstrate that our approach is best than other genre categorization approaches.
Abstract: Software and applications are subjected to serious and damaging security threats, these threats are increasing as a result of increased number of potential vulnerabilities. Security testing is an indispensable process to validate software security requirements and to identify security related vulnerabilities. In this paper we analyze and compare different available vulnerabilities testing techniques based on a pre defined criteria using analytical hierarchy process (AHP). We have selected five testing techniques which includes Source code analysis, Fault code injection, Robustness, Stress and Penetration testing techniques. These testing techniques have been evaluated against five criteria which include cost, thoroughness, Ease of use, effectiveness and efficiency. The outcome of the study is helpful for researchers, testers and developers to understand effectiveness of each technique in its respective domain. Also the study helps to compare the inner working of testing techniques against a selected criterion to achieve optimum testing results.
Abstract: The modeling of water transfer in the unsaturated zone
uses techniques and methods of the soil physics to solve the
Richards-s equation. However, there is a disaccord between the size
of the measurements provided by the soil physics and the size of the
fields of hydrological modeling problem, to which is added the
strong spatial variability of soil hydraulic properties. The objective of
this work was to develop a methodology to estimate the
hydrodynamic parameters for modeling water transfers at different
hydrological scales in the soil-plant atmosphere systems.
Abstract: Cerium oxide is to be recovered from monazite,
which contains about 27.35% CeO2. The principal objective
of this study is to be able to extract cerium oxide from
monazite of Moemeik Myitsone Area. The treatment of
monazite in this study involves three main steps; extraction
of cerium hydroxide from monazite, solvent extraction of
cerium hydroxide, and precipitation with oxalic acid and
calcination of cerium oxalate.
Abstract: This paper presents an automatic feature recognition
method based on center-surround difference detecting and fuzzy logic
that can be applied in ground-penetrating radar (GPR) image
processing. Adopted center-surround difference method, the salient
local image regions are extracted from the GPR images as features of
detected objects. And fuzzy logic strategy is used to match the
detected features and features in template database. This way, the
problem of objects detecting, which is the key problem in GPR image
processing, can be converted into two steps, feature extracting and
matching. The contributions of these skills make the system have the
ability to deal with changes in scale, antenna and noises. The results of
experiments also prove that the system has higher ratio of features
sensing in using GPR to image the subsurface structures.
Abstract: The purpose of this paper is to analyze the case of the
U.S. Pivot and to suggest an appropriate model including entry
strategies and success factors for QPS of Cable TV. The
telecommunication companies have been operating QPS including
IPTV service, which enables them to cross over broadcasting areas.
Due to this circumstance, the Cable TV operators are now concerned
and are planning to add QPS with the mobile service. Based on the
Porter's five forces model, an analytical framework has been proposed
to MVNO in Cable TV industry in the United States. As a result of this
study, MVNO in Cable TV industry has to have a clear killer
application with their sufficient contents. Subsequently, the direction
of the future Cable TV industry is proposed.
Abstract: Single nucleotide polymorphisms (SNPs) hold much promise as a basis for disease-gene association. However, research is limited by the cost of genotyping the tremendous number of SNPs. Therefore, it is important to identify a small subset of informative SNPs, the so-called tag SNPs. This subset consists of selected SNPs of the genotypes, and accurately represents the rest of the SNPs. Furthermore, an effective evaluation method is needed to evaluate prediction accuracy of a set of tag SNPs. In this paper, a genetic algorithm (GA) is applied to tag SNP problems, and the K-nearest neighbor (K-NN) serves as a prediction method of tag SNP selection. The experimental data used was taken from the HapMap project; it consists of genotype data rather than haplotype data. The proposed method consistently identified tag SNPs with considerably better prediction accuracy than methods from the literature. At the same time, the number of tag SNPs identified was smaller than the number of tag SNPs in the other methods. The run time of the proposed method was much shorter than the run time of the SVM/STSA method when the same accuracy was reached.
Abstract: Not many studies have been undertaken on shareholder activism in emerging economies, including Malaysia. Shareholder activism in emerging economies is on the rise. This paper seeks to comprehend the elements of this activism that are unique to Malaysia, specifically with respect to how the agency problem is controlled through shareholder activism in improving corporate governance practices within target companies. Through shareholder activism, shareholders make contact with a target company to voice their dissatisfaction, suggestions, or recommendations. This paper utilises agency theory to explain institutional shareholder activism. This theory has been extensively used within literature on corporate governance with regards to shareholder activism. The effectiveness of shareholder activism in improving corporate governance will be examined as well. This research provides a further understanding of shareholder activism in emerging economies, such as Malaysia; this research also has the potential to enhance shareholder activism and corporate governance practices in general.
Abstract: The electrolyte stirring method of anodization etching
process for manufacturing porous silicon (PS) is reported in this work.
Two experimental setups of nature air stirring (PS-ASM) and
electrolyte stirring (PS-ESM) are employed to clarify the influence of
stirring mechanisms on electrochemical etching process. Compared to
traditional fabrication without any stirring apparatus (PS-TM), a large
plateau region of PS surface structure is obtained from samples with
both stirring methods by the 3D-profiler measurement. Moreover, the
light emission response is also improved by both proposed electrolyte
stirring methods due to the cycling force in electrolyte could
effectively enhance etch-carrier distribution while the electrochemical
etching process is made. According to the analysis of statistical
calculation of photoluminescence (PL) intensity, lower standard
deviations are obtained from PS-samples with studied stirring methods,
i.e. the uniformity of PL-intensity is effectively improved. The
calculated deviations of PL-intensity are 93.2, 74.5 and 64,
respectively, for PS-TM, PS-ASM and PS-ESM.
Abstract: The potential of economically cheaper cellulose
containing natural materials like rice husk was assessed for nickel
adsorption from aqueous solutions. The effects of pH, contact time,
sorbent dose, initial metal ion concentration and temperature on the
uptake of nickel were studied in batch process. The removal of nickel
was dependent on the physico-chemical characteristics of the
adsorbent, adsorbate concentration and other studied process
parameters. The sorption data has been correlated with Langmuir,
Freundlich and Dubinin-Radush kevich (D-R) adsorption models. It
was found that Freundlich and Langmuir isotherms fitted well to the
data. Maximum nickel removal was observed at pH 6.0. The
efficiency of rice husk for nickel removal was 51.8% for dilute
solutions at 20 g L-1 adsorbent dose. FTIR, SEM and EDAX were
recorded before and after adsorption to explore the number and
position of the functional groups available for nickel binding on to
the studied adsorbent and changes in surface morphology and
elemental constitution of the adsorbent. Pseudo-second order model
explains the nickel kinetics more effectively. Reusability of the
adsorbent was examined by desorption in which HCl eluted 78.93%
nickel. The results revealed that nickel is considerably adsorbed on
rice husk and it could be and economic method for the removal of
nickel from aqueous solutions.
Abstract: Since polymerase chain reaction (PCR) has been
invented, it has emerged as a powerful tool in genetic analysis. The
PCR products are closely linked with thermal cycles. Therefore, to
reduce the reaction time and make temperature distribution uniform in
the reaction chamber, a novel oscillatory thermal cycler is designed.
The sample is placed in a fixed chamber, and three constant isothermal
zones are established and lined in the system. The sample is oscillated
and contacted with three different isothermal zones to complete
thermal cycles. This study presents the design of the geometric
characteristics of the chamber. The commercial software
CFD-ACE+TM is utilized to investigate the influences of various
materials, heating times, chamber volumes, and moving speed of the
chamber on the temperature distributions inside the chamber. The
chamber moves at a specific velocity and the boundary conditions
with time variations are related to the moving speed. Whereas the
chamber moves, the boundary is specified at the conditions of the
convection or the uniform temperature. The user subroutines compiled
by the FORTRAN language are used to make the numerical results
realistically. Results show that the reaction chamber with a rectangular
prism is heated on six faces; the effects of various moving speeds of
the chamber on the temperature distributions are examined. Regarding
to the temperature profiles and the standard deviation of the
temperature at the Y-cut cross section, the non-uniform temperature
inside chamber is found as the moving speed is larger than 0.01 m/s.
By reducing the heating faces to four, the standard deviation of the
temperature of the reaction chamber is under 1.4×10-3K with the range
of velocities between 0.0001 m/s and 1 m/s. The nature convective
boundary conditions are set at all boundaries while the chamber moves
between two heaters, the effects of various moving velocities of the
chamber on the temperature distributions are negligible at the assigned
time duration.
Abstract: Five original strains of entomopathogenic bacteria
with insecticidal activity against mosquito larvae of the genera Aedes,
Culex and Anopheles have been isolated from natural conditions in
Armenia and characterized. According to morphological,
physiological and biochemical parameters, all isolates were identified
as Bacillus thuringiensis spp. israelensis (Bti). High larvicidal
activity has been showed by three strains Bti. These strains can be
recommended for industrial production of bacterial preparations.
Abstract: Traffic enforcement units (the Police) are partly
responsible for the severity and frequency of the traffic accidents via
the effectiveness of their safety measures. The Police claims that the
reductions in accidents and their severities occur largely by their
timely interventions at the black spots, through traffic management
or temporary changes in the road design (guiding, reducing speeds
and eliminating sight obstructions, etc.). Yet, some other external
factors than the Police measures may intervene into which such
claims require a statistical confirmation. In order to test the net
impact of the Police contribution in the reduction of the number of
crashes, Chi square test was applied for 25 spots (streets and
intersections) and an average evaluation was achieved for general
conclusion in the case study of Izmir city. Separately, the net impact
of economic crisis in the reduction of crashes is assessed by the
trend analysis for the case of the economic crisis with the probable
reduction effects on the trip generation or modal choice. Finally, it
was proven that the Police measures were effective to some degree as
they claimed, though the economic crisis might have only negligible
contribution to the reductions in the same period observed.
Abstract: The notion of communicative competence has been deemed fuzzy in communication studies. This fuzziness has led to tensions among engineers across tenures in interpreting what constitutes communicative competence. The study seeks to investigate novice and professional engineers- understanding of the said notion in terms of two main elements of communicative competence: linguistic and rhetorical competence. Novice engineers are final year engineering students, whilst professional engineers represent engineers who have at least 5 years working experience. Novice and professional engineers were interviewed to gauge their perceptions on linguistic and rhetorical features deemed necessary to enhance communicative competence for the profession. Both groups indicated awareness and differences on the importance of the sub-sets of communicative competence, namely, rhetorical explanatory competence, linguistic oral immediacy competence, technical competence and meta-cognitive competence. Such differences, a possible attribute of the learning theory, inadvertently indicate sublime differences in the way novice and professional engineers perceive communicative competence.