Abstract: In this paper, vapour-liquid critical locus for the
binary system acetone + chloroform was determined experimentally
over the whole range of composition. The critical property
measurements were carried out using a dynamic-synthetic apparatus,
employed in the dynamic mode. The critical points are visually
determined by observing the critical opalescence and the
simultaneous disappearance and reappearance of the meniscus in the
middle of a high-pressure view cell which withstands operations up
to 673K and 20MPa. The experimental critical points measured in
this work were compared to those available in literature.
Abstract: This paper proposes an innovative methodology for
Acceptance Sampling by Variables, which is a particular category of
Statistical Quality Control dealing with the assurance of products
quality. Our contribution lies in the exploitation of machine learning
techniques to address the complexity and remedy the drawbacks of
existing approaches. More specifically, the proposed methodology
exploits Artificial Neural Networks (ANNs) to aid decision making
about the acceptance or rejection of an inspected sample. For any
type of inspection, ANNs are trained by data from corresponding
tables of a standard-s sampling plan schemes. Once trained, ANNs
can give closed-form solutions for any acceptance quality level and
sample size, thus leading to an automation of the reading of the
sampling plan tables, without any need of compromise with the
values of the specific standard chosen each time. The proposed
methodology provides enough flexibility to quality control engineers
during the inspection of their samples, allowing the consideration of
specific needs, while it also reduces the time and the cost required for
these inspections. Its applicability and advantages are demonstrated
through two numerical examples.
Abstract: The ferroelectric behavior of barium strontium
titanate (BST) in thin film form has been investigated in order to
study the possibility of using BST for ferroelectric gate-field effect
transistor (FeFET) for memory devices application. BST thin films
have been fabricated as Al/BST/Pt/SiO2/Si-gate configuration. The
variation of the dielectric constant (ε) and tan δ with frequency have
been studied to ensure the dielectric quality of the material. The
results show that at low frequencies, ε increases as the Ba content
increases, whereas at high frequencies, it shows the opposite
variation, which is attributed to the dipole dynamics. tan δ shows low
values with a peak at the mid-frequency range. The ferroelectric
behavior of the Al/BST/Pt/SiO2/Si has been investigated using C-V
characteristics. The results show that the strength of the ferroelectric
hysteresis loop increases as the Ba content increases; this is attributed
to the grain size and dipole dynamics effect.
Abstract: We study the performance of compressed beamforming
weights feedback technique in generalized triangular decomposition
(GTD) based MIMO system. GTD is a beamforming technique that
enjoys QoS flexibility. The technique, however, will perform at its
optimum only when the full knowledge of channel state information
(CSI) is available at the transmitter. This would be impossible in
the real system, where there are channel estimation error and limited
feedback. We suggest a way to implement the quantized beamforming
weights feedback, which can significantly reduce the feedback data,
on GTD-based MIMO system and investigate the performance of
the system. Interestingly, we found that compressed beamforming
weights feedback does not degrade the BER performance of the
system at low input power, while the channel estimation error
and quantization do. For comparison, GTD is more sensitive to
compression and quantization, while SVD is more sensitive to the
channel estimation error. We also explore the performance of GTDbased
MU-MIMO system, and find that the BER performance starts
to degrade largely at around -20 dB channel estimation error.
Abstract: Recently, the findings on the MEG iterative scheme has demonstrated to accelerate the convergence rate in solving any system of linear equations generated by using approximation equations of boundary value problems. Based on the same scheme, the aim of this paper is to investigate the capability of a family of four-point block iterative methods with a weighted parameter, ω such as the 4 Point-EGSOR, 4 Point-EDGSOR, and 4 Point-MEGSOR in solving two-dimensional elliptic partial differential equations by using the second-order finite difference approximation. In fact, the formulation and implementation of three four-point block iterative methods are also presented. Finally, the experimental results show that the Four Point MEGSOR iterative scheme is superior as compared with the existing four point block schemes.
Abstract: The article deals with pneumatic and hot wire
anemometry measurement on subsonic axi-symmetric air ejector.
Performances of the ejector with and without pulsations of primary
flow are compared, measuring of characteristic pressures and mass
flow rates are performed and ejector efficiency is evaluated. The
pulsations of primary flow are produced by a synthetic jet generator,
which is placed in the supply line of the primary flow just in front of
the primary nozzle. The aim of the pulsation is to intensify the
mixing process. In the article we present: Pressure measuring of
pulsation on the mixing chamber wall, behind the mixing chamber
and behind the diffuser measured by fast pressure transducers and
results of hot wire anemometry measurement. It was found out that
using of primary flow pulsations yields higher back pressure behind
the ejector and higher efficiency. The processes in this ejector and
influences of primary flow pulsations on the mixing processes are
described.
Abstract: The design of an active leg orthosis for tumble
protection is proposed in this paper. The orthosis would be applied to
assist elders or invalids in rebalancing while they fall unexpectedly.
We observe the regain balance motion of healthy and youthful people,
and find the difference to elders or invalids. First, the physical model
of leg would be established, and we consider the leg motions are
achieve through four joints (phalanx stem, ankle, knee, and hip joint)
and five links (phalanges, talus, tibia, femur, and hip bone). To
formulate the dynamic equations, the coordinates which can clearly
describe the position in 3D space are first defined accordance with the
human movement of leg, and the kinematics and dynamics of the leg
movement can be formulated based on the robotics. For the purpose,
assisting elders and invalids in avoiding tumble, the posture variation
of unbalance and regaining balance motion are recorded by the
motion-capture image system, and the trajectory is taken as the desire
one. Then we calculate the force and moment of each joint based on
the leg motion model through programming MATLAB code. The
results would be primary information of the active leg orthosis design
for tumble protection.
Abstract: In this article the authors are researching cultural
differences between rural and urban characters in case of
contemporary Kazakh cinema.Two motion pictures are analyzed:
“Strizh" (2007) by AbaiKulbai and “Seker" (2009) by
SabitKurmanbekov.According to the authors- opinion ateenage girl
characters in these two films reflect two cultures (urban and rural) of
Kazakh society, which displays complicated socio-cultural processes
of modern Kazakhstan.
Abstract: Antioxidant activities of ethanolic extracts of Ardisia
japonica Blume., Ageartum conyzoides Linn., and Cocculus hirsutus
Linn Diels. leaves was determined qualitatively and quantitatively in
this research. 1, 1-diphenyl-2-picrylhydrazyl (DPPH) free radical
solution was used to investigate free radical scavenging activity of
these leaves extracts. Ascorbic acid (Vitamin C) was used as the
standard. In the present investigation, it is found that all of these
extracts have remarkable antioxidant activities. The EC50 values of
these ethanolic extracts were 12.72 μg/ml for A. japonica, 15.19
μg/ml for A. conyzoides, 10.68 μg/ml for C. hirsutus respectively.
Among these Myanmar medicinal plants, C. hirsutus showed higher
antioxidant activities as well as free radical scavenging activity than
black tea (Camellia sinensis), the famous antioxidant, and A.
japonica and A. conyzoides showed a rather lower antioxidant
activity than tea extracts. According to results from bioassay with
carrot discs infected with Agrobacterium tumefaciens, all extracts
showed anti-tumor activity after 3 weeks of incubation. No gall was
detected in carrot disks treated with C. hirsutus and A. japonica
extracts in the dose of 100ppm and in carrot discs treated with A.
conyzoides extract in the dose of 1000 ppm. Therefore, the research
clearly indicates that these weedy plants of dry farm land are
exceptionally advantageous for human health.
Abstract: The indistinctness of the manufacturing processes makes that a parts cannot be realized in an absolutely exact way towards the specifications on the dimensions. It is thus necessary to assume that the effectively realized product has to belong in a very strict way to compatible intervals with a correct functioning of the parts. In this paper we present an approach based on mixing tow different characteristics theories, the fuzzy system and Petri net system. This tool has been proposed to model and control the quality in an assembly system. A robust command of a mechanical assembly process is presented as an application. This command will then have to maintain the specifications interval of parts in front of the variations. It also illustrates how the technique reacts when the product quality is high, medium, or low.
Abstract: The interline power flow controller (IPFC) is one of
the latest generation flexible AC transmission systems (FACTS)
controller used to control power flows of multiple transmission lines.
This paper presents a mathematical model of IPFC, termed as power
injection model (PIM). This model is incorporated in Newton-
Raphson (NR) power flow algorithm to study the power flow control
in transmission lines in which IPFC is placed. A program in
MATLAB has been written in order to extend conventional NR
algorithm based on this model. Numerical results are carried out on a
standard 2 machine 5 bus system. The results without and with IPFC
are compared in terms of voltages, active and reactive power flows to
demonstrate the performance of the IPFC model.
Abstract: This paper investigates the optimization problem of
multi-product aggregate production planning (APP) with fuzzy data.
From a comprehensive viewpoint of conserving the fuzziness of input
information, this paper proposes a method that can completely
describe the membership function of the performance measure. The
idea is based on the well-known Zadeh-s extension principle which
plays an important role in fuzzy theory. In the proposed solution
procedure, a pair of mathematical programs parameterized by
possibility level a is formulated to calculate the bounds of the
optimal performance measure at a . Then the membership function of
the optimal performance measure is constructed by enumerating
different values of a . Solutions obtained from the proposed method
contain more information, and can offer more chance to achieve the
feasible disaggregate plan. This is helpful to the decision-maker in
practical applications.
Abstract: Studies on residential satisfaction have been actively
discussed under family house setting. However, limited studies have
been conducted on student residential satisfaction. This study is an
attempt to fill the research gap. It focuses on the influence of socioeconomic
on students- satisfaction with the universities- student
housing facilities. The students who stayed at the on-campus student
housing were the respondents. This study employed two-stage cluster
sampling method in classifying the respondents. Self-administered
questionnaires were distributed face-to-face to the students. In
general, it is confirmed that students- socio-economic backgrounds
have influence on the students- satisfaction with their housing
facilities. The main influential factors were the students- economic
status, sense of sharing, and ethnicity of their roommates.
Furthermore, this study could also provide a useful feedback for the
universities in order to improve their student housing facilities.
Abstract: Taking into account the link between the efficiency of
a detector and the complexity of a stealth mechanism, we propose in
this paper a new formalism for stealth using graph theory.
Abstract: Lignocellulosic materials are new targeted source to
produce second generation biofuels like biobutanol. However, this
process is significantly resisted by the native structure of biomass.
Therefore, pretreatment process is always essential to remove
hemicelluloses and lignin prior to the enzymatic hydrolysis.
The goals of pretreatment are removing hemicelluloses and
lignin, increasing biomass porosity, and increasing the enzyme
accessibility. The main goal of this research is to study the important
variables such as pretreatment temperature and time, which can give
the highest total sugar yield in pretreatment step by using dilute
phosphoric acid. After pretreatment, the highest total sugar yield of
13.61 g/L was obtained under an optimal condition at 140°C for 10
min of pretreatment time by using 1.75% (w/w) H3PO4 and at 15:1
liquid to solid ratio. The total sugar yield of two-stage process
(pretreatment+enzymatic hydrolysis) of 27.38 g/L was obtained.
Abstract: This paper deals with the thermo-mechanical deformation behavior of shear deformable functionally graded ceramicmetal (FGM) plates. Theoretical formulations are based on higher order shear deformation theory with a considerable amendment in the transverse displacement using finite element method (FEM). The mechanical properties of the plate are assumed to be temperaturedependent and graded in the thickness direction according to a powerlaw distribution in terms of the volume fractions of the constituents. The temperature field is supposed to be a uniform distribution over the plate surface (XY plane) and varied in the thickness direction only. The fundamental equations for the FGM plates are obtained using variational approach by considering traction free boundary conditions on the top and bottom faces of the plate. A C0 continuous isoparametric Lagrangian finite element with thirteen degrees of freedom per node have been employed to accomplish the results. Convergence and comparison studies have been performed to demonstrate the efficiency of the present model. The numerical results are obtained for different thickness ratios, aspect ratios, volume fraction index and temperature rise with different loading and boundary conditions. Numerical results for the FGM plates are provided in dimensionless tabular and graphical forms. The results proclaim that the temperature field and the gradient in the material properties have significant role on the thermo-mechanical deformation behavior of the FGM plates.
Abstract: Kuwait-s electric power system is vertically integrated
organization owned and operated by the government. For more than
five decades, the government of Kuwait has provided relatively
reliable electric services to consumers with subsidized electric
service fees. Given the country-s rapid socio-economical
development and consequently the increase of electricity demand, a
question that inflicts itself: Is it necessary to reform the power system
to face the fast growing demand? This paper recommends that the
government should consider the private sector as a partner in
operating the power system. Therefore, power system restructuring is
needed to allow such partnership. There are challenges that prevent
such restructuring. Abstract recommendations toward resolving these
challenges are proposed.
Abstract: In the previous multi-solid models,¤ò approach is
used for the calculation of fugacity in the liquid phase. For the first
time, in the proposed multi-solid thermodynamic model,γ approach
has been used for calculation of fugacity in the liquid mixture.
Therefore, some activity coefficient models have been studied that
the results show that the predictive Wilson model is more appropriate
than others. The results demonstrate γ approach using the predictive
Wilson model is in more agreement with experimental data than the
previous multi-solid models. Also, by this method, generates a new
approach for presenting stability analysis in phase equilibrium
calculations. Meanwhile, the run time in γ approach is less than the
previous methods used ¤ò approach. The results of the new model
present 0.75 AAD % (Average Absolute Deviation) from the
experimental data which is less than the results error of the previous
multi-solid models obviously.
Abstract: Resource-constrained project scheduling is an NPhard
optimisation problem. There are many different heuristic
strategies how to shift activities in time when resource requirements
exceed their available amounts. These strategies are frequently based
on priorities of activities. In this paper, we assume that a suitable
heuristic has been chosen to decide which activities should be
performed immediately and which should be postponed and
investigate the resource-constrained project scheduling problem
(RCPSP) from the implementation point of view. We propose an
efficient routine that, instead of shifting the activities, extends their
duration. It makes it possible to break down their duration into active
and sleeping subintervals. Then we can apply the classical Critical
Path Method that needs only polynomial running time. This
algorithm can simply be adapted for multiproject scheduling with
limited resources.
Abstract: This study employs a bivariate asymmetric GARCH
model to reveal the hidden dynamics price changes and volatility
among the emerging markets of Thailand and Malaysian after the
Asian financial crisis from January 2001 to December 2008. Our
results indicated that the equity markets are sharing the common
information (shock) that transmitted among each others. These
empirical findings are used to demonstrate the importance of shock
and volatility dynamic transmissions in the cross-market hedging and
market risk.