Abstract: Supersonic open and closed cavity flows are investigated experimentally and computationally. Free stream Mach number of two is set. Schlieren imaging is used to visualise the flow behaviour showing stark differences between open and closed. Computational Fluid Dynamics (CFD) is used to simulate open cavity of flow with aspect ratio of 4. A rear wall treatment is implemented in order to pursue a simple passive control approach. Good qualitative agreement is achieved between the experimental flow visualisation and the CFD in terms of the expansion-shock waves system. The cavity oscillations are shown to be dominated by the first and third Rossister modes combining to high fluctuations of non-linear nature above the cavity rear edge. A simple rear wall treatment in terms of a hole shows mixed effect on the flow oscillations, RMS contours, and time history density fluctuations are given and analysed.
Abstract: The distillation process in the general sense is a
relatively simple technique from the standpoints of its principles.
When dedicating distillation to water treatment and specifically
producing fresh water from sea, ocean and/ briny waters it is
interesting to notice that distillation has no limitations or domains of
applicability regarding the nature or the type of the feedstock water.
This is not the case however for other techniques that are
technologically quite complex, necessitate bigger capital investments
and are limited in their usability. In a previous paper we have
explored some of the effects of temperature on yield. In this paper,
we continue building onto that knowledge base and focus on the
effects of several additional engineering and design variables on
productivity.
Abstract: This paper presents a fuzzy control system for a three degree of freedom (3-DOF) stabilized platform with explicit decoupling scheme. The system under consideration is a system with strong interactions between three channels. By using the concept of decentralized control, a control structure is developed that is composed of three control loops, each of which is associated with a single-variable fuzzy controller and a decoupling unit. Takagi-Sugeno (TS) fuzzy control algorithm is used to implement the fuzzy controller. The decoupling units design is based on the adaptive theory reasoning. Simulation tests were established using Simulink of Matlab. The obtained results have demonstrated the feasibility and effectiveness of the proposed approach. Simulation results are represented in this paper.
Abstract: Well-developed strategic marketing planning is the essential
prerequisite for establishment of the right and unique competitive
advantage. Typical market, however, is a heterogeneous
and decentralized structure with natural involvement of individual
or group subjectivity and irrationality. These features cannot be
fully expressed with one-shot rigorous formal models based on,
e.g. mathematics, statistics or empirical formulas. We present an
innovative solution, extending the domain of agent based computational
economics towards the concept of hybrid modeling in service
provider and consumer market such as telecommunications. The
behavior of the market is described by two classes of agents -
consumer and service provider agents - whose internal dynamics
are fundamentally different. Customers are rather free multi-state
structures, adjusting behavior and preferences quickly in accordance
with time and changing environment. Producers, on the contrary,
are traditionally structured companies with comparable internal processes
and specific managerial policies. Their business momentum is
higher and immediate reaction possibilities limited. This limitation
underlines importance of proper strategic planning as the main
process advising managers in time whether to continue with more
or less the same business or whether to consider the need for future
structural changes that would ensure retention of existing customers
or acquisition of new ones.
Abstract: Climate change and environmental pressures are
major international issues nowadays. It is time when governments,
businesses and consumers have to respond through more
environmentally friendly and aware practices, products and policies.
This is the prime time to develop alternative sustainable construction
materials, reduce greenhouse gas emissions, save energy, look to
renewable energy sources and recycled materials, and reduce waste.
The utilization of waste materials (slag, fly ash, glass beads, plastic
and so on) in concrete manufacturing is significant due to its
engineering, financial, environmental and ecological benefits. Thus,
utilization of waste materials in concrete production is very much
helpful to reach the goal of the sustainable construction. Therefore,
this study intends to use glass beads in concrete production.
The paper reports on the performance of 9 different concrete
mixes containing different ratios of glass crushed to 5 mm - 20 mm
maximum size and glass marble of 20 mm size as coarse aggregate.
Ordinary Portland cement type 1 and fine sand less than 0.5 mm were
used to produce standard concrete cylinders. Compressive strength
tests were carried out on concrete specimens at various ages. Test
results indicated that the mix having the balanced ratio of glass beads
and round marbles possess maximum compressive strength which is
3889 psi, as glass beads perform better in bond formation but have
lower strength, on the other hand marbles are strong in themselves
but not good in bonding. These mixes were prepared following a
specific W/C and aggregate ratio; more strength can be expected to
achieve from different W/C, aggregate ratios, adding admixtures like
strength increasing agents, ASR inhibitor agents etc.
Abstract: Desert regions around the Nile valley in Upper Egypt
contain great extent of swelling soil. Many different comment
procedures of treatment of the swelling soils for construction such as
pre-swelling, load balance OR soil replacement. One of the measure
factors which affect the level of the aggressiveness of the swelling
soil is the direction of the infiltration water directions within the
swelling soils. In this paper a physical model was installed to
measure the effect of water on the swelling soil with replacement
using fatty acid distillation residuals (FADR) mixed with sand as
thick sand-FADR mixture to prevent the water pathway arrive to the
swelling soil. Testing program have been conducted on different
artificial samples with different sand to FADR contents ratios (4%,
6%, and 9%) to get the optimum value fulfilling the impermeable
replacement. The tests show that a FADR content of 9% is sufficient
to produce impermeable replacement.
Abstract: Determining how many virtual machines a Linux host
could run can be a challenge. One of tough missions is to find the
balance among performance, density and usability. Now KVM
hypervisor has become the most popular open source full
virtualization solution. It supports several ways of running guests with
more memory than host really has. Due to large differences between
minimum and maximum guest memory requirements, this paper
presents initial results on same-page merging, ballooning and live
migration techniques that aims at optimum memory usage on
KVM-based cloud platform. Given the design of initial experiments,
the results data is worth reference for system administrators. The
results from these experiments concluded that each method offers
different reliability tradeoff.
Abstract: Asphalt surfaces are exposed to various weather
conditions and dynamic loading caused by passing trucks and
vehicles. In such situations, asphalt cement shows so different
rheological-mechanical behavior. If asphalt cement isn-t compatible
enough, asphalt layer will be damaged immediately and expensive
repairing procedures should be performed then. To overcome this
problem, researchers study on mechanical improved asphalt cement.
In this study, bentonite was used in order to modify bitumen
characteristics and the modified bitumen's characteristics were
investigated by asphalt cement tests. Then, the optimal bitumen
content in various compounds was determined and asphalt samples
with different contents of additives were prepared and tested. Results
show using this kind of additive not only has caused improvement in
bitumen mechanical properties, but also improvement in Marshall
Parameters was achieved.
Abstract: In this paper, the problem of asymptotical stability of neutral systems with nonlinear perturbations is investigated. Based on a class of novel augment Lyapunov functionals which contain freeweighting matrices, some new delay-dependent asymptotical stability criteria are formulated in terms of linear matrix inequalities (LMIs) by using new inequality analysis technique. Numerical examples are given to demonstrate the derived condition are much less conservative than those given in the literature.
Abstract: Phaseolus coccineus L. is the third most important
cultivated Phaseolus species in the world. It is widely grown in
Latvia due to its earliness, good taste and uniform and qualitative
yield. Experiments were carried out in the laboratories of Department
of Food Technology and Agronomical Analysis Scientific Laboratory
at Latvia Universityof Agriculture. Beans (Phaseolus coccineus L.)
crude protein, crude ash content as well as colour measurements were
analyzed. Results show, that brown coloured beans have less crude
protein content than others, and ash content have significant
differences.
Abstract: There are a many of needs for the development of
SiC-based hydrogen sensor for harsh environment applications. We
fabricated and investigated Pd/Ta2O5/SiC-based hydrogen sensors
with MOS capacitor structure for high temperature process monitoring
and leak detection applications in such automotive, chemical and
petroleum industries as well as direct monitoring of combustion
processes. In this work, we used silicon carbide (SiC) as a substrate to
replace silicon which operating temperatures are limited to below
200°C. Tantalum oxide was investigated as dielectric layer which has
high permeability for hydrogen gas and high dielectric permittivity,
compared with silicon dioxide or silicon nitride. Then, electrical
response properties, such as I-V curve and dependence of capacitance
on hydrogen concentrations were analyzed in the temperature ranges
of room temperature to 500°C for performance evaluation of the
sensor.
Abstract: The roll center is one of the key parameters for designing a suspension. Several driving characteristics are affected significantly by the migration of the roll center during the suspension-s motion. The strut/SLA (strut/short-long-arm) suspension, which is widely used in production cars, combines the space-saving characteristics of a MacPherson strut suspension with some of the preferred handling characteristics of an SLA suspension. In this study, a front strut/SLA suspension is modeled by ADAMS/Car software. Kinematic roll analysis is then employed to investigate how the rolling characteristics change under the wheel travel and steering input. The related parameters, including the roll center height, roll camber gain, toe change, scrub radius and wheel track width change, are analyzed and discussed. It is found that the strut/SLA suspension clearly has a higher roll center than strut and SLA suspensions do. The variations in the roll center height under roll analysis are very different as the wheel travel displacement and steering angle are added. The results of the roll camber gain, scrub radius and wheel track width change are considered satisfactory. However, the toe change is too large and needs fine-tuning through a sensitivity analysis.
Abstract: This paper presents an authoring tool which makes a
user easily and intuitively design vibrotactile sensation. A mobile
hardware platform powered by ANDROID, a multi-purpose haptic
driver and a linear resonance actuator are used to implement the
system of the presented authoring tool. The tool allows users to easily
and simply create a vibrotactile sensation by drawing vibrotactile
images and to feel the sensation by rubbing drawn images on the touch
screen of a mobile device. The tool supports a graphical interface for
designing, editing and playing vibrotactile images as well as a
pre-defined file format for save and open.
Abstract: Kwashiorkor is one of nutritional problem in
Indonesia, which lead to decrease immune system. This condition
causes susceptibility to infectious disease, especially tuberculosis.
Development of new tuberculosis vaccine will be an important
strategy to eliminate tuberculosis in kwashiorkor. Previous research
showed that 38-kDa Mycobacterium tuberculosis protein is one of the
potent immunogen. However, the role of oral immunization with 38-
kDa Mycobacterium tuberculosis protein to the number of
lymphocytes in the rat model of kwashiorkor is still unknown. We
used kwashiorkor rat model groups with 4% and 2% low protein diet.
Oral immunization with 38-kDa Mycobacterium tuberculosis protein
given with 2 booster every week. The lymphocytes number were
measured by flowcytometry. There was no significant difference
between the number of lymphocytes in the normal rat group and the
kwashiorkor rat groups. It may reveal the role of 38-kDa
Mycobacterium tuberculosis protein as a potent immunogen that can
increase the lymphocytes number from kwashiorkor rat model same
as normal rat.
Abstract: Classification of electroencephalogram (EEG) signals
extracted during mental tasks is a technique that is actively pursued
for Brain Computer Interfaces (BCI) designs. In this paper, we
compared the classification performances of univariateautoregressive
(AR) and multivariate autoregressive (MAR) models
for representing EEG signals that were extracted during different
mental tasks. Multilayer Perceptron (MLP) neural network (NN)
trained by the backpropagation (BP) algorithm was used to classify
these features into the different categories representing the mental
tasks. Classification performances were also compared across
different mental task combinations and 2 sets of hidden units (HU): 2
to 10 HU in steps of 2 and 20 to 100 HU in steps of 20. Five different
mental tasks from 4 subjects were used in the experimental study and
combinations of 2 different mental tasks were studied for each
subject. Three different feature extraction methods with 6th order
were used to extract features from these EEG signals: AR
coefficients computed with Burg-s algorithm (ARBG), AR
coefficients computed with stepwise least square algorithm (ARLS)
and MAR coefficients computed with stepwise least square
algorithm. The best results were obtained with 20 to 100 HU using
ARBG. It is concluded that i) it is important to choose the suitable
mental tasks for different individuals for a successful BCI design, ii)
higher HU are more suitable and iii) ARBG is the most suitable
feature extraction method.
Abstract: In this paper, we propose a new method to distinguish
between arousal and relaxation states by using multiple features
acquired from a photoplethysmogram (PPG) and support vector
machine (SVM). To induce arousal and relaxation states in subjects, 2
kinds of sound stimuli are used, and their corresponding biosignals are
obtained using the PPG sensor. Two features–pulse to pulse interval
(PPI) and pulse amplitude (PA)–are extracted from acquired PPG
data, and a nonlinear classification between arousal and relaxation is
performed using SVM.
This methodology has several advantages when compared with
previous similar studies. Firstly, we extracted 2 separate features from
PPG, i.e., PPI and PA. Secondly, in order to improve the classification
accuracy, SVM-based nonlinear classification was performed.
Thirdly, to solve classification problems caused by generalized
features of whole subjects, we defined each threshold according to
individual features.
Experimental results showed that the average classification
accuracy was 74.67%. Also, the proposed method showed the better
identification performance than the single feature based methods.
From this result, we confirmed that arousal and relaxation can be
classified using SVM and PPG features.
Abstract: The urban transformation processes in its framework
and its general significance became a fundamental and vital subject
of consideration for both the developed and the developing societies.
It has become important to regulate the architectural systems adopted
by the city, to sustain the present development on one hand, and on
the other hand, to facilitate its future growth.
Thus, the study dealt with the phenomenon of urban
transformation of the Mediterranean cities, and the city of Alexandria
in particular, because of its significant historical and cultural legacy,
its historical architecture and its contemporary urbanization.
This article investigates the entirety of cities in the Mediterranean
region through the analysis of the relationship between inflation and
growth of these cities and the extent of the complexity of the city
barriers. We hope to analyze not only the internal transformations,
but the external relationships (both imperial and post-colonial) that
have shaped Alexandria city growth from the nineteenth century until
today.
Abstract: Manufacturing companies are facing a broad variety
of challenges caused by a dynamic production environment. To
succeed in such an environment, it is crucial to minimize the loss of
time required to trigger the adaptation process of a company-s
production structures. This paper presents an approach for the
continuous monitoring of production structures by neurologic
principles. It enhances classical monitoring concepts, which are
principally focused on reactive strategies, and enables companies to
act proactively. Thereby, strategic aspects regarding the
harmonization of certain life cycles are integrated into the decision
making process for triggering the reconfiguration process of the
production structure.
Abstract: Internet application in China has maintained a constant
development tendency in the past decade. China is now one of the
most populous countries in terms of internet user population. While
offering enormous opportunities, the dramatic digitalization also
brings about a series of challenges that demand urgent attention.
Digital divide is one of the challenges that affect China as well as other
countries in the world. This paper examines digital divide in the
Chinese context from the perspective of development communication.
Through a case study of a rural township under the backdrop of the
rapid internet development in China, the paper discusses the
economic, psychological and cultural roots of digital divide; and
explores development communication strategies addressing the roots
of digital divide. It is argued that development communication must be
responsive to the potentialities and preferences of the specific society
and serve the purposes of participation and sustainability.
Abstract: Importance of strategic planning is unquestionable. However, the practical implementation of a strategic plan faces too many obstacles. The aim of the article is explained the importance of strategic planning and to find how companies in Moravian-Silesian Region deal with strategic planning, and to introduce the model, which helps to set strategic goals in financial indicators area. This model should be part of the whole process of strategic planning and can be use to predict the future values of financial indicators of the company with regard to the factor, which influence these indicators.