Abstract: This paper presented a novel combined cycle of air separation and natural gas liquefaction. The idea is that natural gas can be liquefied, meanwhile gaseous or liquid nitrogen and oxygen are produced in one combined cryogenic system. Cycle simulation and exergy analysis were performed to evaluate the process and thereby reveal the influence of the crucial parameter, i.e., flow rate ratio through two stages expanders β on heat transfer temperature difference, its distribution and consequent exergy loss. Composite curves for the combined hot streams (feeding natural gas and recycled nitrogen) and the cold stream showed the degree of optimization available in this process if appropriate β was designed. The results indicated that increasing β reduces temperature difference and exergy loss in heat exchange process. However, the maximum limit value of β should be confined in terms of minimum temperature difference proposed in heat exchanger design standard and heat exchanger size. The optimal βopt under different operation conditions corresponding to the required minimum temperature differences was investigated.
Abstract: Waste lubricating oil re-refining adsorption process by
different adsorbent materials was investigated. Adsorbent materials
such as oil adsorbent, egg shale powder, date palm kernel powder,
and acid activated date palm kernel powder were used. The
adsorption process over fixed amount of adsorbent at ambient
conditions was investigated. The adsorption/extraction process was
able to deposit the asphaltenic and metallic contaminants from the
waste oil to lower values. It was found that the date palm kernel
powder with contact time of 4 h was able to give the best conditions
for treating the waste oil. The recovered solvent could be also reused.
It was also found that the activated bentonite gave the best
physical properties followed by the date palm kernel powder.
Abstract: Cavitation in pumps is known as the formation of
vapor bubbles due to pressure drop and collapsing these bubbles. In
some conditions, it has been observed that the formation of bubbles
occurs at the pressure side of centrifugal pump blades. In this study,
the formation of bubbles at the pressure side of blades has been
investigated. Water is used in this study as the fluid and performance
curves were depicted for different flow rates in an approximately
constant speed. The results show that when a centrifugal pump works
in low flow rates, a secondary flow namely recirculation starts to
begin. In this condition, separation of flow increases which causes
vortex formation and local pressure drop and eventually the
formation of vapor bubbles starts.
Abstract: These Nowadays the explosion of bombs or explosive
materials such as gas and oil near or inside the buildings cause some
losses in installations and building components. This has made the
engineers to make the buildings and their components resistance
against the effects of explosion. These activities lead to provide
regulations and different methods. The above regulations are mostly
focused on the explosion effects resulting from the vehicles around
the buildings. Therefore, the explosion resulting from the vehicles
outside the buildings will be studied in this research.
In the present study, the main goals are to investigate the
explosion load effects on the structures located on the piles with the
specific quantity of plasticity and observing the permissible response
of these structures. The concentrated mass system and the spring with
two degree of freedom will be used to study the structural system.
Abstract: The anti-lock braking systems installed on vehicles
for safe and effective braking, are high-order nonlinear and timevariant.
Using fuzzy logic controllers increase efficiency of such
systems, but impose a high computational complexity as well. The
main concept introduced by this paper is reducing computational
complexity of fuzzy controllers by deploying problem-solution data
structure. Unlike conventional methods that are based on
calculations, this approach is based on data oriented modeling.
Abstract: Relay based communication has gained considerable importance in the recent years. In this paper we find the end-toend statistics of a two hop non-regenerative relay branch, each hop being Nakagami-m faded. Closed form expressions for the probability density functions of the signal envelope at the output of a selection combiner and a maximal ratio combiner at the destination node are also derived and analytical formulations are verified through computer simulation. These density functions are useful in evaluating the system performance in terms of bit error rate and outage probability.
Abstract: In this research study, an intelligent detection system
to support medical diagnosis and detection of abnormal lesions by
processing endoscopic images is presented. The images used in this
study have been obtained using the M2A Swallowable Imaging
Capsule - a patented, video color-imaging disposable capsule.
Schemes have been developed to extract texture features from the
fuzzy texture spectra in the chromatic and achromatic domains for a
selected region of interest from each color component histogram of
endoscopic images. The implementation of an advanced fuzzy
inference neural network which combines fuzzy systems and
artificial neural networks and the concept of fusion of multiple
classifiers dedicated to specific feature parameters have been also
adopted in this paper. The achieved high detection accuracy of the
proposed system has provided thus an indication that such intelligent
schemes could be used as a supplementary diagnostic tool in
endoscopy.
Abstract: At very high speeds, bubbles form in the underwater vehicles because of sharp trailing edges or of places where the local pressure is lower than the vapor pressure. These bubbles are called cavities and the size of the cavities grows as the velocity increases. A properly designed cavitator can induce the formation of a single big cavity all over the vehicle. Such a vehicle travelling in the vaporous cavity is called a supercavitating vehicle and the present research work mainly focuses on the dynamic modeling of such vehicles. Cavitation of the fins is also accounted and the effect of the same on trajectory is well explained. The entire dynamics has been developed using the state space approach and emphasis is given on the effect of size and angle of attack of the cavitator. Control law has been established for the motion of the vehicle using Non-linear Dynamic Inverse (NDI) with cavitator as the control surface.
Abstract: Healthcare issues continue to pose huge problems and incur massive costs. As a result there are many challenging problems still unresolved. In this paper, we will carry out an extensive scientific survey of different areas of management and planning in an attempt to identify where there has already been a substantial contribution from management science methods to healthcare problems and where there is a clear potential for more work to be done. The focus will be on the read-across to the healthcare domain from such approaches applied generally to management and planning and how the methods can be used to improvement patient care. We conclude that, since the healthcare domain significantly differs from traditional areas of management and planning, in some cases there is a need to modify the approaches so as to incorporate the complexities of healthcare, and fully exploit the potential for improvement.
Abstract: Many states are now committed to implementing
international human rights standards domestically. In terms of
practical governance, how might effectiveness be measured? A facevalue
answer can be found in domestic laws and institutions relating
to human rights. However, this article provides two further tools to
help states assess their status on the spectrum of robust to fragile
human rights governance. The first recognises that each state has its
own 'human rights history' and the ideal end stage is robust human
rights governance, and the second is developing criteria to assess
robustness. Although a New Zealand case study is used to illustrate
these tools, the widespread adoption of human rights standards by
many states inevitably means that the issues are relevant to other
countries. This is even though there will always be varying degrees of
similarity-difference in constitutional background and developed or
emerging human rights systems.
Abstract: The purpose of this study is two-fold. First, it attempts to explore potential opportunities for utilizing visual interactive simulations along with Business Intelligence (BI) as a decision support tool for strategic decision making. Second, it tries to figure out the essential top-level managerial requirements that would transform strategic decision simulation into an integral component of BI systems. The domain of particular interest was the application of visual interactive simulation capabilities in the field of supply chains. A qualitative exploratory method was applied, through the use of interviews with two leading companies. The collected data was then analysed to demonstrate the difference between the literature perspective and the practical managerial perspective on the issue. The results of the study suggest that although the use of simulation particularly in managing supply chains is very evident in literature, yet, in practice such utilization is still in its infancy, particularly regarding strategic decisions. Based on the insights a prototype of a simulation based BI-solution-extension was developed and evaluated.
Abstract: This paper proposes a new methodology for the
optimal allocation and sizing of Embedded Generation (EG)
employing Real Coded Genetic Algorithm (RCGA) to minimize the
total power losses and to improve voltage profiles in the radial
distribution networks. RCGA is a method that uses continuous
floating numbers as representation which is different from
conventional binary numbers. The RCGA is used as solution tool,
which can determine the optimal location and size of EG in radial
system simultaneously. This method is developed in MATLAB. The
effect of EG units- installation and their sizing to the distribution
networks are demonstrated using 24 bus system.
Abstract: Human activities are increasingly based on the use of remote resources and services, and on the interaction between
remotely located parties that may know little about each other. Mobile agents must be prepared to execute on different hosts with
various environmental security conditions. The aim of this paper is to
propose a trust based mechanism to improve the security of mobile
agents and allow their execution in various environments. Thus, an
adaptive trust mechanism is proposed. It is based on the dynamic interaction between the agent and the environment. Information
collected during the interaction enables generation of an environment
key. This key informs on the host-s trust degree and permits the mobile agent to adapt its execution. Trust estimation is based on
concrete parameters values. Thus, in case of distrust, the source of problem can be located and a mobile agent appropriate behavior can
be selected.
Abstract: This paper presents design trade-off and performance impacts of
the amount of pipeline phase of control path signals in a wormhole-switched
network-on-chip (NoC). The numbers of the pipeline phase of the control
path vary between two- and one-cycle pipeline phase. The control paths
consist of the routing request paths for output selection and the arbitration
paths for input selection. Data communications between on-chip routers are
implemented synchronously and for quality of service, the inter-router data
transports are controlled by using a link-level congestion control to avoid
lose of data because of an overflow. The trade-off between the area (logic
cell area) and the performance (bandwidth gain) of two proposed NoC router
microarchitectures are presented in this paper. The performance evaluation is
made by using a traffic scenario with different number of workloads under
2D mesh NoC topology using a static routing algorithm. By using a 130-nm
CMOS standard-cell technology, our NoC routers can be clocked at 1 GHz,
resulting in a high speed network link and high router bandwidth capacity
of about 320 Gbit/s. Based on our experiments, the amount of control path
pipeline stages gives more significant impact on the NoC performance than
the impact on the logic area of the NoC router.
Abstract: A state of the art Speaker Identification (SI) system
requires a robust feature extraction unit followed by a speaker
modeling scheme for generalized representation of these features.
Over the years, Mel-Frequency Cepstral Coefficients (MFCC)
modeled on the human auditory system has been used as a standard
acoustic feature set for speech related applications. On a recent
contribution by authors, it has been shown that the Inverted Mel-
Frequency Cepstral Coefficients (IMFCC) is useful feature set for
SI, which contains complementary information present in high
frequency region. This paper introduces the Gaussian shaped filter
(GF) while calculating MFCC and IMFCC in place of typical
triangular shaped bins. The objective is to introduce a higher
amount of correlation between subband outputs. The performances
of both MFCC & IMFCC improve with GF over conventional
triangular filter (TF) based implementation, individually as well as
in combination. With GMM as speaker modeling paradigm, the
performances of proposed GF based MFCC and IMFCC in
individual and fused mode have been verified in two standard
databases YOHO, (Microphone Speech) and POLYCOST
(Telephone Speech) each of which has more than 130 speakers.
Abstract: Recent developments in information and
communication technologies (ICT) have created excellent conditions
for profoundly enhancing the traditional learning and teaching
practices. New modes of teaching in higher education subjects can
profoundly enhance ones ability to proactively constructing his or her
personal learning universe. These developments have contributed to
digital learning environments becoming widely available and
accessible. In addition, there is a trend towards enlargement and
specialization in higher education in Europe. With as a result that
existing Master of Science (MSc) programmes are merged or new
programmes have been established that are offered as joint MSc
programmes to students. In these joint MSc programmes, the need for
(common) digital learning environments capable of surmounting the
barriers of time and location has become evident. This paper
discusses the past and ongoing efforts to establish such common
digital learning environments in two joint MSc programmes in
Europe and discusses the way technology-based learning
environments affect the traditional way of learning.
Abstract: This paper focuses on the Mega-Sub Controlled
Structure Systems (MSCSS) performances and characteristics
regarding the new control principle contained in MSCSS subjected to
strong earthquake excitations. The adopted control scheme consists of
modulated sub-structures where the control action is achieved by
viscous dampers and sub-structure own configuration. The
elastic-plastic time history analysis under severe earthquake excitation
is analyzed base on the Finite Element Analysis Method (FEAM), and
some comparison results are also given in this paper. The result shows
that the MSCSS systems can remarkably reduce vibrations effects
more than the mega-sub structure (MSS). The study illustrates that the
improved MSCSS presents good seismic resistance ability even at 1.2g
and can absorb seismic energy in the structure, thus imply that
structural members cross section can be reduce and achieve to good
economic characteristics. Furthermore, the elasto-plastic analysis
demonstrates that the MSCSS is accurate enough regarding
international building evaluation and design codes. This paper also
shows that the elasto-plastic dynamic analysis method is a reasonable
and reliable analysis method for structures subjected to strong
earthquake excitations and that the computed results are more precise.
Abstract: In diversity rich environments, such as in Ultra-
Wideband (UWB) applications, the a priori determination of the
number of strong diversity branches is difficult, because of the considerably large number of diversity paths, which are characterized
by a variety of power delay profiles (PDPs). Several
Rake implementations have been proposed in the past, in order to reduce the number of the estimated and combined paths. To this
aim, we introduce two adaptive Rake receivers, which combine
a subset of the resolvable paths considering simultaneously the
quality of both the total combining output signal-to-noise ratio (SNR) and the individual SNR of each path. These schemes achieve
better adaptation to channel conditions compared to other known receivers, without further increasing the complexity. Their performance
is evaluated in different practical UWB channels, whose models are based on extensive propagation measurements. The
proposed receivers compromise between the power consumption,
complexity and performance gain for the additional paths, resulting in important savings in power and computational resources.
Abstract: This study presents the improvement of thermal
performance of heat pipe using copper nanofluid with aqueous
solution of n-Butanol. The nanofluids kept in the suspension of
conventional fluids have the potential of superior heat transfer
capability than the conventional fluids due to their improved thermal
conductivity. In this work, the copper nanofluid which has a 40 nm
size with a concentration of 100 mg/lit is kept in the suspension of
the de-ionized (DI) water and an aqueous solution of n-Butanol and
these fluids are used as a working medium in the heat pipe. The study
discusses about the effect of heat pipe inclination, type of working
fluid and heat input on the thermal efficiency and thermal resistance.
The experimental results are evaluated in terms of its performance
metrics and are compared with that of DI water.
Abstract: This study was designed to formulate,
pharmaceutically evaluate a topical skin-care cream (w/o emulsion)
of Aloe Vera versus its vehicle (Base) as control and determine their
effects on Stratum Corneum (SC) water content and Transepidermal
water loss (TEWL). Base containing no extract and a Formulation
containing 3% concentrated extract of Aloe Vera was developed by
entrapping in the inner aqueous phase of w/o emulsion (cream).
Lemon oil was incorporated to improve the odor. Both the Base and
Formulation were stored at 8°C ±0.1°C (in refrigerator), 25°C±0.1°C,
40°C±0.1°C and 40°C± 0.1°C with 75% RH (in incubator) for a
period of 4 weeks to predict their stability. The evaluation parameters
consisted of color, smell, type of emulsion, phase separation,
electrical conductivity, centrifugation, liquefaction and pH. Both the
Base and Formulation were applied to the cheeks of 21 healthy
human volunteers for a period of 8 weeks Stratum corneum (SC)
water content and Transepidermal water loss (TEWL) were
monitored every week to measure any effect produced by these
topical creams. The expected organoleptic stability of creams was
achieved from 4 weeks in-vitro study period. Odor was disappeared
with the passage of time due to volatilization of lemon oil. Both the
Base and Formulation produced significant (p≤0.05) changes in
TEWL with respect to time. SC water content was significantly
(p≤0.05) increased by the Formulation while the Base has
insignificant (p 0.05) effects on SC water content. The newly
formulated cream of Aloe Vera, applied is suitable for improvement
and quantitative monitoring of skin hydration level (SC water
content/ moisturizing effects) and reducing TEWL in people with dry
skin.