Abstract: Technology, multimedia in Open Educational
Resources, can contribute positively to student performance in an
online instructional environment. Student performance data of past
four years were obtained from an online course entitled Applied
Calculus (MA139). This paper examined the data to determine
whether multimedia (independent variable) had any impact on
student performance (dependent variable) in online math learning,
and how students felt about the value of the technology. Two groups
of student data were analyzed, group 1 (control) from the online
applied calculus course that did not use multimedia instructional
materials, and group 2 (treatment) of the same online applied calculus
course that used multimedia instructional materials. For the MA139
class, results indicate a statistically significant difference (p = .001)
between the two groups, where group 1 had a final score mean of
56.36 (out of 100), group 2 of 70.68. Additionally, student
testimonials were discussed in which students shared their experience
in learning applied calculus online with multimedia instructional
materials.
Abstract: Image enhancement is a challenging issue in many applications. In the last two decades, there are various filters developed. This paper proposes a novel method which removes Gaussian noise from the gray scale images. The proposed technique is compared with Enhanced Fuzzy Peer Group Filter (EFPGF) for various noise levels. Experimental results proved that the proposed filter achieves better Peak-Signal-to-Noise-Ratio PSNR than the existing techniques. The proposed technique achieves 1.736dB gain in PSNR than the EFPGF technique.
Abstract: Chrome tannery wastewater causes serious environmental hazard due to its high pollution potential. As a result, rigorous treatment is necessary for abatement of pollution from this type of wastewater. There are many research studies on chrome tannery wastewater treatment in the field of physical, chemical, and biological methods. In general, biological treatment process is found ineffective for direct application because of adverse effects by toxic chromium, sulphide, chloride etc. However, biological methods were employed mainly for a few sub processes generating significant amount of organic matter and without chromium, chlorides etc. In this context the present paper reviews the characteristics feature and pollution potential of wastewater generated from chrome tannery units and treatment of the same. The different biological processes used earlier and their chronological development for treatment of the chrome tannery wastewater are thoroughly reviewed in this paper. In this regard, the scope of hybrid bioreactor - an advanced technology option has also been explored, as this kind of treatment is well suited for the wastewater having inhibitory substances.
Abstract: In this study, ultrasonic assisted machining (UAM) technique is applied in side-surface milling experiment for glass-ceramic workpiece material. The tungsten carbide cutting-tool with diamond coating is used in conjunction with two kinds of cooling/lubrication mediums such as water-soluble (WS) cutting fluid and minimum quantity lubricant (MQL). Full factorial process parameter combinations on the milling experiments are planned to investigate the effect of process parameters on cutting performance. From the experimental results, it tries to search for the better process parameter combination which the edge-indentation and the surface roughness are acceptable. In the machining experiments, ultrasonic oscillator was used to excite a cutting-tool along the radial direction producing a very small amplitude of vibration frequency of 20KHz to assist the machining process. After processing, toolmaker microscope was used to detect the side-surface morphology, edge-indentation and cutting tool wear under different combination of cutting parameters, and analysis and discussion were also conducted for experimental results. The results show that the main leading parameters to edge-indentation of glass ceramic are cutting depth and feed rate. In order to reduce edge-indentation, it needs to use lower cutting depth and feed rate. Water-soluble cutting fluid provides a better cooling effect in the primary cutting area; it may effectively reduce the edge-indentation and improve the surface morphology of the glass ceramic. The use of ultrasonic assisted technique can effectively enhance the surface finish cleanness and reduce cutting tool wear and edge-indentation.
Abstract: The paper presents the trends of Georgian hazelnut market development and analyses the competitive advantages which will help Georgia to enter international hazelnut market using modern technologies. The history of hazelnut crop development and hazelnut varieties in Georgia are discussed. For hazelnut supply analysis trends in hazelnut production are considered, trends in export and import development is evaluated, domestic hazelnut market is studied and analysed based on expert interviews and initial accounting materials. In order to achieve and strengthen its position in international market, potential advantages and disadvantages of Georgian hazelnut are revealed, analysis of export and import possibilities of hazelnut is presented. Recommendations are developed based on the conclusions, which are made through identifying the key factors that hinder development of Georgian hazelnut market.
Abstract: Wavelength Division Multiplexing (WDM) is the dominant transport technology used in numerous high capacity backbone networks, based on optical infrastructures. Given the importance of costs (CapEx and OpEx) associated to these networks, resource management is becoming increasingly important, especially how the optical circuits, called “lightpaths”, are routed throughout the network. This requires the use of efficient algorithms which provide routing strategies with the lowest cost. We focus on the lightpath routing and wavelength assignment problem, known as the RWA problem, while optimizing wavelength fragmentation over the network. Wavelength fragmentation poses a serious challenge for network operators since it leads to the misuse of the wavelength spectrum, and then to the refusal of new lightpath requests. In this paper, we first establish a new Integer Linear Program (ILP) for the problem based on a node-link formulation. This formulation is based on a multilayer approach where the original network is decomposed into several network layers, each corresponding to a wavelength. Furthermore, we propose an efficient heuristic for the problem based on a greedy algorithm followed by a post-treatment procedure. The obtained results show that the optimal solution is often reached. We also compare our results with those of other RWA heuristic methods
Abstract: In this paper static scheme of under-frequency based load shedding is considered for chemical and petrochemical industries with islanded distribution networks relying heavily on the primary commodity to ensure minimum production loss, plant downtime or critical equipment shutdown. A simplistic methodology is proposed for in-house implementation of this scheme using underfrequency relays and a step by step guide is provided including the techniques to calculate maximum percentage overloads, frequency decay rates, time based frequency response and frequency based time response of the system. Case study of FFL electrical system is utilized, presenting the actual system parameters and employed load shedding settings following the similar series of steps. The arbitrary settings are then verified for worst overload conditions (loss of a generation source in this case) and comprehensive system response is then investigated.
Abstract: Hydrothermal liquefaction (HTL) is a technique for obtaining clean biofuel from biomass in the presence of heat and pressure in an aqueous medium which leads to a decomposition of this biomass to the formation of various products. A role of operating conditions is essential for the bio-oil and other products’ yield and also quality of the products. The effects of these parameters were investigated in regards to the composition and yield of the products. Chlorellaceae microalgae were tested under different HTL conditions to clarify suitable conditions for extracting bio-oil together with value-added co-products. Firstly, different microalgae loading rates (5-30%) were tested and found that this parameter has not much significant to product yield. Therefore, 10% microalgae loading rate was selected as a proper economical solution for conditioned schedule at 250oC and 30 min-reaction time. Next, a range of temperature (210-290oC) was applied to verify the effects of each parameter by keeping the reaction time constant at 30 min. The results showed no linkage with the increase of the reaction temperature and some reactions occurred that lead to different product yields. Moreover, some nutrients found in the aqueous product are possible to be utilized for nutrient recovery.
Abstract: This paper presents dynamic models of distributed
generators (DG) and investigates dynamic behavior of the DG units
in the micro grid system. The DG units include photovoltaic and fuel
cell sources. The voltage source inverter is adopted since the
electronic interface which can be equipped with its controller to keep
stability of the micro grid during small signal dynamics. This paper
also introduces power management strategies and implements the DG
load sharing concept to keep the micro grid operation in gridconnected
and islanding modes of operation. The results demonstrate
the operation and performance of the photovoltaic and fuel cell as
distributed generators in a micro grid. The entire control system in
the micro grid is developed by combining the benefits of the power
control and the voltage control strategies. Simulation results are all
reported, confirming the validity of the proposed control technique.
Abstract: In this research the effect of moisture at three levels
(47, 57, and 67 w.b.%) on the physical properties of the Pofaki pea
variety including, dimensions, geometric mean diameter, volume,
sphericity index and the surface area was determined. The influence
of different moisture levels (47, 57 and 67 w.b.%), in two loading
orientation (longitudinal and transverse) and three loading speed (4,6
and 8 mm min-1) on the mechanical properties of pea such as
maximum deformation, rupture force, rupture energy, toughness and
the power to break the pea was investigated. It was observed in the
physical properties that moisture changes were affective at 1% on,
dimensions, geometric mean diameter, volume, sphericity index and
the surface area. It was observed in the mechanical properties that
moisture changes were effective at 1% on, maximum deformation,
rupture force, rupture energy, toughness and the power to break.
Loading speed was effective on maximum deformation, rupture
force, rupture energy at 1% and it was effective on toughness at 5%.
Loading orientation was effective on maximum deformation, rupture
force, rupture energy, toughness at 1% and it was effective on power
at 5%. The mutual effect of speed and orientation were effective on
rupture energy at 1% and were effective on toughness at 5%
probability. The mutual effect of moisture and speed were effective
on rupture force and rupture energy at 1% and were effective on
toughness 5% probability. The mutual effect of orientation and
moisture on rupture energy and toughness were effective at 1%.
Abstract: The paper is focused on the identification of limiting
environmental factors of individual industrial floors on which newly
developed polymer protection and repair systems with the use of
secondary raw materials will be used. These mainly include floors
with extreme stresses and special requirements for materials used. In
relation to the environment of a particular industrial floor, it is
necessary to ensure, for example, chemical stability, resistance to
higher temperatures, resistance to higher mechanical stress, etc. for
developed materials, which is reflected in the demands for the
developed material systems. The paper describes individual
environments and, in relation to them, also requirements for
individual components of the developed materials and for the
developed materials as a whole.
Abstract: This paper deals with the theoretical and numerical
investigation of magneto hydrodynamic boundary layer flow of a
nanofluid past a wedge shaped wick in heat pipe used for the cooling
of electronic components and different type of machines. To
incorporate the effect of nanoparticle diameter, concentration of
nanoparticles in the pure fluid, nanothermal layer formed around the
nanoparticle and Brownian motion of nanoparticles etc., appropriate
models are used for the effective thermal and physical properties of
nanofluids. To model the rotation of nanoparticles inside the base
fluid, microfluidics theory is used. In this investigation ethylene
glycol (EG) based nanofluids, are taken into account. The non-linear
equations governing the flow and heat transfer are solved by using a
very effective particle swarm optimization technique along with
Runge-Kutta method. The values of heat transfer coefficient are
found for different parameters involved in the formulation viz.
nanoparticle concentration, nanoparticle size, magnetic field and
wedge angle etc. It is found that, the wedge angle, presence of
magnetic field, nanoparticle size and nanoparticle concentration etc.
have prominent effects on fluid flow and heat transfer characteristics
for the considered configuration.
Abstract: This paper presents a part of the project solving which
is dedicated to the identification of the hazardous waste with the most
critical production within the Czech Republic with the aim to study
and find the optimal composition of the cement matrix that will
ensure maximum content disposal of chosen hazardous waste. In the
first stage of project solving – which represents this paper – a specific
hazardous waste was chosen, its properties were identified and
suitable solidification agents were chosen. Consequently
solidification formulas and testing methodology was proposed.
Abstract: Moving into a new era of healthcare, new tools and
devices are developed to extend and improve health services, such as
remote patient monitoring and risk prevention. In this concept,
Internet of Things (IoT) and Cloud Computing present great
advantages by providing remote and efficient services, as well as
cooperation between patients, clinicians, researchers and other health
professionals. This paper focuses on patients suffering from bipolar
disorder, a brain disorder that belongs to a group of conditions
called affective disorders, which is characterized by great mood
swings. We exploit the advantages of Semantic Web and Cloud
Technologies to develop a patient monitoring system to support
clinicians. Based on intelligently filtering of evidence-knowledge and
individual-specific information we aim to provide treatment
notifications and recommended function tests at appropriate times or
concluding into alerts for serious mood changes and patient’s nonresponse
to treatment. We propose an architecture as the back-end
part of a cloud platform for IoT, intertwining intelligence devices
with patients’ daily routine and clinicians’ support.
Abstract: This paper presents the design and fabrication of an
optical window for an optical modulator toward image sensing
applications. An optical window consists of micrometer-order SiO2
capillaries (porous solid) that can modulate transmission light
intensity by moving the liquid in and out of porous solid. A high
optical transmittance of the optical window can be achieved due to
refractive index matching when the liquid is penetrated into the
porous solid. Otherwise, its light transmittance is lower because of
light reflection and scattering by air holes and capillary walls. Silicon
capillaries fabricated by deep reactive ion etching (DRIE) process are
completely oxidized to form the SiO2 capillaries. Therefore, high
aspect ratio SiO2 capillaries can be achieved based on silicon
capillaries formed by DRIE technique. Large compressive stress of
the oxide causes bending of the capillary structure, which is reduced
by optimizing the design of device structure. The large stress of the
optical window can be released via thin supporting beams. A 7.2 mm
x 9.6 mm optical window area toward a fully integrated with the
image sensor format is successfully fabricated and its optical
transmittance is evaluated with and without inserting liquids (ethanol
and matching oil). The achieved modulation range is approximately
20% to 35% with and without liquid penetration in visible region
(wavelength range from 450 nm to 650 nm).
Abstract: Exact solution of an unsteady MHD flow of elasticoviscous
fluid through a porous media in a tube of spherical cross
section under the influence of magnetic field and constant pressure
gradient has been obtained in this paper. Initially, the flow is
generated by a constant pressure gradient. After attaining the steady
state, the pressure gradient is suddenly withdrawn and the resulting
fluid motion in a tube of spherical cross section by taking into
account of the porosity factor and magnetic parameter of the
bounding surface is investigated. The problem is solved in two-stages
the first stage is a steady motion in tube under the influence of a
constant pressure gradient, the second stage concern with an unsteady
motion. The problem is solved employing separation of variables
technique. The results are expressed in terms of a non-dimensional
porosity parameter (K), magnetic parameter (m) and elasticoviscosity
parameter (β), which depends on the Non-Newtonian
coefficient. The flow parameters are found to be identical with that of
Newtonian case as elastic-viscosity parameter and magnetic
parameter tends to zero and porosity tends to infinity. It is seen that
the effect of elastico-viscosity parameter, porosity parameter and
magnetic parameter of the bounding surface has significant effect on
the velocity parameter.
Abstract: The main objective of this paper is to provide a new
methodology for road safety assessment in Oman through the
development of suitable accident prediction models. GLM technique
with Poisson or NBR using SAS package was carried out to develop
these models. The paper utilized the accidents data of 31 un-signalized
T-intersections during three years. Five goodness-of-fit
measures were used to assess the overall quality of the developed
models. Two types of models were developed separately; the flow-based
models including only traffic exposure functions, and the full
models containing both exposure functions and other significant
geometry and traffic variables.
The results show that, traffic exposure functions produced much
better fit to the accident data. The most effective geometric variables
were major-road mean speed, minor-road 85th percentile speed,
major-road lane width, distance to the nearest junction, and right-turn
curb radius.
The developed models can be used for intersection treatment or
upgrading and specify the appropriate design parameters of T-intersections.
Finally, the models presented in this thesis reflect the intersection
conditions in Oman and could represent the typical conditions in
several countries in the middle east area, especially gulf countries.
Abstract: The number of persons with implanted cardiac
pacemakers (PM) has increased in Western countries. The aim of this
paper is to investigate the possible situations where persons with a
PM may be exposed to extremely low frequency (ELF) electric (EF)
and magnetic fields (MF) that may disturb their PM. Based on our
earlier studies, it is possible to find such high public exposure to EFs
only in some places near 400 kV power lines, where an EF may
disturb a PM in unipolar mode. Such EFs cannot be found near 110
kV power lines. Disturbing MFs can be found near welding
machines. However, we do not have measurement data from welding.
Based on literature and earlier studies at Tampere University of
Technology, it is difficult to find public EF or MF exposure that is
high enough to interfere with PMs.
Abstract: This paper presents a novel integrated hybrid
approach for fault diagnosis (FD) of nonlinear systems. Unlike most
FD techniques, the proposed solution simultaneously accomplishes
fault detection, isolation, and identification (FDII) within a unified
diagnostic module. At the core of this solution is a bank of adaptive
neural parameter estimators (NPE) associated with a set of singleparameter
fault models. The NPEs continuously estimate unknown
fault parameters (FP) that are indicators of faults in the system. Two
NPE structures including series-parallel and parallel are developed
with their exclusive set of desirable attributes. The parallel scheme is
extremely robust to measurement noise and possesses a simpler, yet
more solid, fault isolation logic. On the contrary, the series-parallel
scheme displays short FD delays and is robust to closed-loop system
transients due to changes in control commands. Finally, a fault
tolerant observer (FTO) is designed to extend the capability of the
NPEs to systems with partial-state measurement.
Abstract: Our globalizing world has become almost a small
village and everyone can access any information at any time.
Everyone lets each other know who does whatever in which place.
We can learn which social events occur in which place in the world.
From the perspective of education, the course notes that a lecturer use
in lessons in a university in any state of America can be examined by
a student studying in a city of Africa or the Far East. This dizzying
communication we have mentioned happened thanks to fast
developments in computer and internet technologies. While these
developments occur in the world, Turkey that has a very large young
population and whose electronic infrastructure rapidly improves has
also been affected by these developments. Nowadays, mobile devices
have become common and thus, it causes to increase data traffic in
social networks. This study was carried out on students in the
different age groups in Selcuk University Vocational School of
Technical Sciences, the Department of Computer Technology.
Students’ opinions about the use of internet and social media were
obtained. The features such as using the Internet and social media
skills, purposes, operating frequency, accessing facilities and tools,
social life and effects on vocational education and so forth were
explored. The positive effects and negative effects of both internet
and social media use on the students in this department and findings
are evaluated from different perspectives and results are obtained. In
addition, relations and differences were found out statistically.