Abstract: To judge whether the memristor can be interpreted as
the fourth fundamental circuit element, we propose a variable-relation
criterion of fundamental circuit elements. According to the criterion,
we investigate the nature of three fundamental circuit elements and the
memristor. From the perspective of variables relation, the memristor
builds a direct relation between the voltage across it and the current
through it, instead of a direct relation between the magnetic flux and
the charge. Thus, it is better to characterize the memristor and the
resistor as two special cases of the same fundamental circuit element,
which is the memristive system in Chua-s new framework. Finally, the
definition of memristor is refined according to the difference between
the magnetic flux and the flux linkage.
Abstract: High purity hydrogen and the valuable by-product of carbon nanotubes (CNTs) can be produced by the methane catalytic decomposition. The methane conversion and the performance of CNTs were determined by the choices of catalysts and the condition of decomposition reaction. In this paper, Ni/MgO and Ni/O-D (oxidized diamond) catalysts were prepared by wetness impregnation method. The effects of reaction temperature and space velocity of methane on the methane conversion were investigated in a fixed-bed. The surface area, structure and micrography were characterized with BET, XPS, SEM, EDS technology. The results showed that the conversion of methane was above 8% within 150 min (T=500) for 33Ni/O-D catalyst and higher than 25% within 120 min (T=650) for 41Ni/MgO catalyst. The initial conversion increased with the increasing temperature of the decomposition reaction, but their catalytic activities decreased rapidly while at too higher temperature. To decrease the space velocity of methane was propitious to promote the methane conversion, but not favor of the hydrogen yields. The appearance of carbon resulted from the methane decomposition lied on the support type and the condition of catalytic reaction. It presented as fiber shape on the surface of Ni/O-D at the relatively lower temperature such as 500 and 550, but as grain shape stacked on and overlayed on the surface of the metal nickel while at 650. The carbon fiber can form on the Ni/MgO surface at 650 and the diameter of the carbon fiber increased with the decreasing space velocity.
Abstract: Re-entrant scheduling is an important search problem
with many constraints in the flow shop. In the literature, a number of
approaches have been investigated from exact methods to
meta-heuristics. This paper presents a genetic algorithm that encodes
the problem as multi-level chromosomes to reflect the dependent
relationship of the re-entrant possibility and resource consumption.
The novel encoding way conserves the intact information of the data
and fastens the convergence to the near optimal solutions. To test the
effectiveness of the method, it has been applied to the
resource-constrained re-entrant flow shop scheduling problem.
Computational results show that the proposed GA performs better than
the simulated annealing algorithm in the measure of the makespan
Abstract: The purpose of this study is to investigate the capacity
of natural Turkish zeolite for NH4-N removal from landfill leachate.
The effects of modification and initial concentration on the removal
of NH4-N from leachate were also investigated. The kinetics of
adsorption of NH4-N has been discussed using three kinetic models,
i.e., the pseudo-second order model, the Elovich equation, the
intraparticle diffuion model. Kinetic parameters and correlation
coefficients were determined. Equilibrium isotherms for the
adsorption of NH4-N were analyzed by Langmuir, Freundlich and
Tempkin isotherm models. Langmuir isotherm model was found to
best represent the data for NH4-N.
Abstract: One of the aims of the paper is to make a comparison
of experimental results with numerical simulation for a side cooler.
Specifically, it was the amount of air to be delivered by the side
cooler with fans running at 100%. This integral value was measured
and evaluated within the plane parallel to the front side of the side
cooler at a distance of 20mm from the front side. The flow field
extending from the side cooler to the space was also evaluated.
Another objective was to address the contribution of evaluated values
to the increase of data center energy consumption.
Abstract: Team efficacy beliefs show promise in enhancing
team performance. Using a model-based quantitative research design,
we investigated the antecedents and performance consequences of
generalized team efficacy (potency) in a sample of 56 capital projects
executed by 15 Fortune 500 companies in the process industries.
Empirical analysis of our field survey identified that generalized
team efficacy beliefs were positively associated with an objective
measure of project cost performance. Regression analysis revealed
that team competence, empowering leadership, and performance
feedback all predicted generalized team efficacy beliefs. Tests of
mediation revealed that generalized team efficacy fully mediated
between these three inputs and project cost performance.
Abstract: Collaborative networked learning (hereafter CNL)
was first proposed by Charles Findley in his work “Collaborative
networked learning: online facilitation and software support" as part
of instructional learning for the future of the knowledge worker. His
premise was that through electronic dialogue learners and experts
could interactively communicate within a contextual framework to
resolve problems, and/or to improve product or process knowledge.
Collaborative learning has always been the forefront of educational
technology and pedagogical research, but not in the mainstream of
operations management. As a result, there is a large disparity in the
study of CNL, and little is known about the antecedents of network
collaboration and sharing of information among diverse employees in
the manufacturing environment. This paper presents a model to
bridge the gap between theory and practice. The objective is that
manufacturing organizations will be able to accelerate organizational
learning and sharing of information through various collaborative
Abstract: Megalopolis is a group of densely populated metropolitan areas that combine to form an urban complex. Since China introduced the economic reforms in late 1970s, the Chinese urban system has experienced unprecedented growth. The process of urbanisation prevailed in the 1980s, and the process of predominantly large city growth appeared to continue through 1990s and 2000s. In this study, the magnitude and pattern of urbanisation in China during 1990s were examined using remotely sensed imagery acquired by TM/ETM+ sensor onboard the Landsat satellites. The development of megalopolis areas in China was also studied based on the GIS analysis of the increases of urban and built-up area from 1990 to 2000. The analysis suggests that in the traditional agricultural zones in China, e.g., Huang-Huai-Hai Plains, Changjiang River Delta, Pearl River Delta and Sichuan Basin, the urban and built-up areas increased by 1.76 million hectares, of which 0.82 million hectares are expansion of urban areas, an increase of 24.78% compared with 1990 at the national scale. The Yellow River Delta, Changjiang River Delta and Pearl River Delta also saw an increase of urban and built-up area by 63.9%, 66.2% and 83.0% respectively. As a result, three major megalopolises were developed in China: the Guangzhou-Shenzhen-Hong Kong- Macau (Pearl River Delta: PRD) megalopolis area, the Shanghai- Nanjing-Hangzhou (Changjiang River Delta: CRD) megalopolis area and the Beijing-Tianjing-Tangshan-Qinhuangdao (Yellow River Delta-Bohai Sea Ring: YRD) megalopolis area. The relationship between the processed of megalopolisation and the inter-provincial population flow was also explored in the context of social-economic and transport infrastructure development in Post-reform China.
Abstract: One of the problems in fault diagnosis of transformer
based on dissolved gas, is lack of matching the result of fault
diagnosis of different standards with the real world. In this paper, the
result of the different standards is analyzed using fuzzy and the result
is compared with the empirical test. The comparison between the
suggested method and existing methods indicate the capability of the
suggested method in on-line fault diagnosis of the transformers. In
addition, in some cases the existing standards are not able to
diagnose the fault. In theses cases, the presented method has the
potential of diagnosing the fault. The information of three
transformers is used to the show the capability of the suggested
method in diagnosing the fault. The results validate the capability of
the presented method in fault diagnosis of the transformer.
Abstract: The toxicity of aqueous extracts of two plants,
Nicotiana tobacum and Eucalyptus globulus were investigated against second instar larvae of Lycoriella auripila, one of the most
important pests of button mushroom, using agar dilution technique.
Seven concentrations of aqueous extracts of both plants were applied
on second instar larvae and their mortality were evaluated after 24, 48 and 72 h. The obtained results revealed that aqueous extracts of N.
tabacum and E. globulus caused 77.55 and 72.5% mortality of larvae
of L. auripila at concentration of 4000 ppm after 72h, respectively. Toxicities of tobacco extract after 24, 48 and 72 h were 1.52, 1.85
and 1.70 times greather than eucalyptus, respectively. The estimated LC50 after 24, 48 and 72 h were 7316.5, 2468.5 and 2013.1 ppm for
tobacco and 64870.0, 6839.5 and 3326.4 ppm for eucalyptus, respectively. These plants merit further study as potential insecticides
for the control of L. auripila.
Abstract: A new mechanism responsible for structural life
consumption due to resonant fatigue in turbine blades, or vanes, is
presented and explained. A rotating blade or vane in a gas turbine can
change its contour due to erosion and/or material build up, in any of
these instances, the surface pressure distribution occurring on the
suction and pressure sides of blades-vanes can suffer substantial
modification of their pressure and temperatures envelopes and flow
characteristics. Meanwhile, the relative rotation between the blade
and duct vane while the pressurized gas flows and the consequent
wake crossings, will induce a fluctuating thrust force or lift that will
excite the blade.
An actual totally used up set of vane-blade components in a HP
turbine power stage in a gas turbine is analyzed. The blade suffered
some material erosion mostly at the trailing edge provoking a
peculiar surface pressure envelope which evolved as the relative
position between the vane and the blade passed in front of each other.
Interestingly preliminary modal analysis for this eroded blade
indicates several natural frequencies within the aeromechanic power
spectrum, moreover, the highest frequency component is 94% of one
natural frequency indicating near resonant condition.
Independently of other simultaneously occurring fatigue cycles
(such as thermal, centrifugal stresses).
Abstract: Until recently it would have been unusual to consider classifying population movements and refugees as security problem. However, efforts at shaping our world to make ourselves secure have paradoxically led to ever greater insecurity. The feeling of uncertainty, pertinent throughout all discourses of security, has led to the creation of security production into seemingly benign routines of everyday life. Yet, the paper argues, neither of security discourses accounted for, disclosed and challenged the fundamental aporias embedded in Western security narratives. In turn, the paper aims to unpick the conventional security wisdom, which is haunted with strong ontologies, embedded in the politics of Orientalism, and (in)security nexus. The paper concludes that current security affair conceals the integral impossibility of fulfilling its very own promise of assured security. The paper also provides suggestions about alternative security discourse based on mutual dialogue.
Abstract: The present article deals with a composite casting process that allows to produce bilayer AlSn6-Al strips based on the technique of horizontal continuous casting. In the first part experimental investigations on the production of a single layer AlSn6 strip are described. Afterwards essential results of basic compound casting trials using simple test specimen are presented to define the thermal conditions required for a metallurgical compound between the alloy AlSn6 and pure aluminium. Subsequently, numerical analyses are described. A finite element model was used to examine a continuous composite casting process. As a result of the simulations the main influencing parameters concerning the thermal conditions within the composite casting region could be pointed out. Finally, basic guidance is given for the design of an appropriate composite mould system.
Abstract: The explosion of interest in online gaming and
virtual worlds is leading many universities to investigate
possible educational applications of the new environments.
In this paper we explore the possibilities of 3D online worlds
for teacher education, particularly the field experience
component. Drawing upon two pedagogical examples, we
suggest that virtual simulations may, with certain limitations,
create safe spaces that allow preservice teachers to adopt
alternate identities and interact safely with the “other." In so
doing they may become aware of the constructed nature of
social categories and gain the essential pedagogical skill of
perspective-taking. We suggest that, ultimately, the ability to
be the principal creators of themselves in virtual environments
can increase their ability to do the same in the real world.
Abstract: This work was to study batch biosorption of Pb(II)
ions from aqueous solution by Luffa charcoal. The effect of operating
parameters such as adsorption contact time, initial pH solution and
different initial Pb(II) concentration on the sorption of Pb(II) were
investigated. The results showed that the adsorption of Pb(II) ions
was initially rapid and the equilibrium time was 10 h. Adsorption
kinetics of Pb(II) ions onto Luffa charcoal could be best described by
the pseudo-second order model. At pH 5.0 was favorable for the
adsorption and removal of Pb(II) ions. Freundlich adsorption
isotherm model was better fitted for the adsorption of Pb(II) ions than
Langmuir and Timkin isotherms, respectively. The highest monolayer
adsorption capacity obtained from Langmuir isotherm model was
51.02 mg/g. This study demonstrated that Luffa charcoal could be
used for the removal of Pb(II) ions in water treatment.
Abstract: Frauds in insurance industry are one of the major
sources of operational risk of insurance companies and constitute a
significant portion of their losses. Every reasonable company on the
market aims for improving their processes of uncovering frauds and
invests their resources to reduce them. This article is addressing fraud
management area from the view of extension of existing Business
Intelligence solution. We describe the frame of such solution and
would like to share with readers all benefits brought to insurance
companies by adopting this approach in their fight against insurance
frauds.
Abstract: Visfatin and apelin are two new adipokines that recently gained a special interest in diabetes research. This study was conducted to study the interplay between these two adipokines and their correlation with other inflammatory and biochemical parameters in type 2 diabetic (T2D) postmenopausal women with CAD. Visfatin and apelin were measured by enzyme-linked immunoassay (ELISA). Visfatin was found to be significantly higher in the following groups: T2D patients without CAD, non-obese and obese T2D patients with CAD when compared to control group. Apelin was found to be significantly lower in non-obese and obese T2D patients with CAD when compared to control group. Visfatin and apelin were found to be significantly associated with each other and with other biochemical parameters. The current study provides evidence for the interplay between visfatin and apelin through the inflammatory milieu characteristic of T2D and their possible role in the pathogenesis of CAD complication of T2D.
Abstract: Magnesium alloy has been widely investigated as
biodegradable cardiovascular stent and bone implant. Its application
for biodegradable esophageal stenting remains unexplored. This
paper reports the biodegradation behaviors of AZ31 magnesium alloy
in artificial saliva and various types of beverage in vitro. Results
show that the magnesium ion release rate of AZ31 in artificial saliva
for a stent (2cm diameter, 10cm length at 50% stent surface
coverage) is 43 times lower than the daily allowance of human body
magnesium intakes. The degradation rates of AZ31 in different
beverages could also be significantly different. These results suggest
that the esophagus in nature is a less aggressive chemical
environment for degradation of magnesium alloys. The significant
difference in degradation rates of AZ31 in different beverages opens
new opportunities for development of degradation controllable
esophageal stent through customizing ingested beverages.
Abstract: Metal cutting is a severe plastic deformation process
involving large strains, high strain rates, and high temperatures.
Conventional analysis of the chip formation process is based on bulk
material deformation disregarding the inhomogeneous nature of the
material microstructure. A series of orthogonal cutting tests of AISI
1045 and 1144 steel were conducted which yielded similar process
characteristics and chip formations. With similar shear angles and cut
chip thicknesses, shear strains for both chips were found to range
from 2.0 up to 2.8. The manganese-sulfide (MnS) precipitate in the
1144 steel has a very distinct and uniform shape which allows for
comparison before and after chip formation. From close observations
of MnS precipitates in the cut chips it is shown that the conventional
approach underestimates plastic strains in metal cutting.
Experimental findings revealed local shear strains around a value of
6. These findings and their implications are presented and discussed.
Abstract: This paper proposes a new model to support user
queries on postgraduate research information at Universiti Tenaga
Nasional. The ontology to be developed will contribute towards
shareable and reusable domain knowledge that makes knowledge
assets intelligently accessible to both people and software. This work
adapts a methodology for ontology development based on the
framework proposed by Uschold and King. The concepts and
relations in this domain are represented in a class diagram using the
Protégé software. The ontology will be used to support a menudriven
query system for assisting students in searching for
information related to postgraduate research at the university.