Abstract: The coaxial transformer-coupled push-pull circuitry
has been used widely in HF and VHF amplifiers for many decades
without significant changes in the topology of the transformers. Basic
changes over the years concerned the construction and turns ratio of
the transformers as has been imposed upon the newer technologies
active devices demands. The balun transmission line transformers
applied in push-pull amplifiers enable input/output impedance
transformation, but are mainly used to convert the balanced output
into unbalanced and the input unbalanced into balanced. A simple
and affordable alternative solution over the traditional coaxial
transformer is the coreless planar balun. A key advantage over the
traditional approach lies in the high specifications repeatability;
simplifying the amplifier construction requirements as the planar
balun constitutes an integrated part of the PCB copper layout. This
paper presents the performance analysis of a planar LDMOS
MRFE6VP5600 Push-Pull amplifier that enables robust operation in
Band III, DVB-T, DVB-T2 standards but functions equally well in
Band II, for DRM+ new generation transmitters.
Abstract: A reliability-based methodology which uses structural demand hazard curves to consider the increment of the ductility demands of structures with tilting is proposed. The approach considers the effect of two orthogonal components of the ground motions as well as the influence of soil-structure interaction. The approach involves the calculation of ductility demand hazard curves for symmetric systems and, alternatively, for systems with different degrees of asymmetry. To get this objective, demand hazard curves corresponding to different global ductility demands of the systems are calculated. Next, Uniform Exceedance Rate Spectra (UERS) are developed for a specific mean annual rate of exceedance value. Ratios between UERS corresponding to asymmetric and to symmetric systems located in soft soil of the valley of Mexico are obtained. Results indicate that the ductility demands corresponding to tilted structures may be several times higher than those corresponding to symmetric structures, depending on several factors such as tilting angle and vibration period of structure and soil.
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: Problems insulation of building structures is often
closely connected with the problem of moisture remediation. In the
case of historic buildings or if only part of the redevelopment of
envelope of structures, it is not possible to apply the classical external
thermal insulation composite systems. This application is mostly
effective thermal insulation plasters with high porosity and controlled
capillary properties which assures improvement of thermal properties
construction, its diffusion openness towards the external environment
and suitable treatment capillary properties of preventing the
penetration of liquid moisture and salts thereof toward the outer
surface of the structure.
With respect to the current trend of reducing the energy
consumption of building structures and reduce the production of CO2
is necessary to develop capillary-active materials characterized by
their low density, low thermal conductivity while maintaining good
mechanical properties. The aim of researchers at the Faculty of Civil
Engineering, Brno University of Technology is the development and
study of hygrothermal behaviour of optimal materials for thermal
insulation and rehabilitation of building structures with the possible
use of alternative, less energy demanding binders in comparison with
conventional, frequently used binder, which represents cement.
The paper describes the evaluation of research activities aimed at
the development of thermal insulation and repair materials using
lightweight aggregate and alternative binders such as metakaolin and
finely ground fly ash.
Abstract: Parabolic solar trough systems have seen limited
deployments in cold northern climates as they are more suitable for
electricity production in southern latitudes. A numerical dynamic
model is developed to simulate troughs installed in cold climates and
validated using a parabolic solar trough facility in Winnipeg. The
model is developed in Simulink and will be utilized to simulate a trigeneration
system for heating, cooling and electricity generation in
remote northern communities. The main objective of this simulation
is to obtain operational data of solar troughs in cold climates and use
the model to determine ways to improve the economics and address
cold weather issues.
In this paper the validated Simulink model is applied to simulate a
solar assisted absorption cooling system along with electricity
generation using Organic Rankine Cycle (ORC) and thermal storage.
A control strategy is employed to distribute the heated oil from solar
collectors among the above three systems considering the
temperature requirements. This modelling provides dynamic
performance results using measured meteorological data recorded
every minute at the solar facility location. The purpose of this
modeling approach is to accurately predict system performance at
each time step considering the solar radiation fluctuations due to
passing clouds. Optimization of the controller in cold temperatures is
another goal of the simulation to for example minimize heat losses in
winter when energy demand is high and solar resources are low.
The solar absorption cooling is modeled to use the generated heat
from the solar trough system and provide cooling in summer for a
greenhouse which is located next to the solar field.
The results of the simulation are presented for a summer day in
Winnipeg which includes comparison of performance parameters of
the absorption cooling and ORC systems at different heat transfer
fluid (HTF) temperatures.
Abstract: Cloud computing is a new technology in industry and
academia. The technology has grown and matured in last half decade
and proven their significant role in changing environment of IT
infrastructure where cloud services and resources are offered over the
network. Cloud technology enables users to use services and
resources without being concerned about the technical implications of
technology. There are substantial research work has been performed
for the usage of cloud computing in educational institutes and
majority of them provides cloud services over high-end blade servers
or other high-end CPUs. However, this paper proposes a new stack
called “CiCKAStack” which provide cloud services over unutilized
computing resources, named as commodity computers.
“CiCKAStack” provides IaaS and PaaS using underlying commodity
computers. This will not only increasing the utilization of existing
computing resources but also provide organize file system, on
demand computing resource and design and development
environment.
Abstract: Today’s VLSI networks demands for high speed. And
in this work the compact form mathematical model for current mode
signalling in VLSI interconnects is presented.RLC interconnect line
is modelled using characteristic impedance of transmission line and
inductive effect. The on-chip inductance effect is dominant at lower
technology node is emulated into an equivalent resistance. First order
transfer function is designed using finite difference equation, Laplace
transform and by applying the boundary conditions at the source and
load termination. It has been observed that the dominant pole
determines system response and delay in the proposed model. The
novel proposed current mode model shows superior performance as
compared to voltage mode signalling. Analysis shows that current
mode signalling in VLSI interconnects provides 2.8 times better
delay performance than voltage mode. Secondly the damping factor
of a lumped RLC circuit is shown to be a useful figure of merit.
Abstract: An innovative concept called “Flexy-Energy” is developing at 2iE. This concept aims to produce electricity at lower cost by smartly mix different available energy sources in accordance to the load profile of the region. With a higher solar irradiation and due to the fact that Diesel generator are massively used in sub-Saharan rural areas, PV/Diesel hybrid systems could be a good application of this concept and a good solution to electrify this region, provided they are reliable, cost effective and economically attractive to investors. Presentation of the developed approach is the aims of this paper. The PV/Diesel hybrid system designed consists to produce electricity and/or heat from a coupling between Diesel Diesel generators and PV panels without batteries storage, while ensuring the substitution of gasoil by bio-fuels available in the area where the system will be installed. The optimal design of this system is based on his technical performances; the Life Cycle Cost (LCC) and Levelized Cost of Energy are developed and use as economic criteria. The Net Present Value (NPV), the internal rate of return (IRR) and the discounted payback (DPB) are also evaluated according to dual electricity pricing (in sunny and unsunny hours). The PV/Diesel hybrid system obtained is compared to the standalone Diesel Diesel generators. The approach carried out in this paper has been applied to Siby village in Mali (Latitude 12 ° 23'N 8 ° 20'W) with 295 kWh as daily demand.This approach provides optimal physical characteristics (size of the components, number of component) and dynamical characteristics in real time (number of Diesel generator on, their load rate, fuel specific consumptions, and PV penetration rate) of the system. The system obtained is slightly cost effective; but could be improved with optimized tariffing strategies.
Abstract: This paper is focusing on the attitude of Georgian
consumers toward social media, influence of social media on
consumer buying behavior. The purpose of this paper is to explore
the usage of social media marketing for small business companies of
Georgia. The result of marketing research has revealed that social
webs are mostly used by Georgian consumers, but they have little
impact on the buying decision. The research method was exploratory
and descriptive. Conclusions summarize the research results and
offers insight to provide better understandings of consumers demand
and implementation of marketing strategy through social media in
Georgia.
Abstract: In Jordan having deficit atmospheric precipitation, an
increase in water demand occurs during summer months. Jordan can
be regarded with a relatively high potential for wastewater recycling
and reuse. The main purpose of this paper was to investigate the
removal of total suspended solids (TSS) and chemical oxygen
demand (COD) for olive mill wastewater (OMW) by
electrocoagulation (EC) process. In the combination of
electrocoagulation by using coupled iron–aluminum electrodes, the
optimum working pH was found to be around 6. Results indicated
that the electrocoagulation process allowed removal of TSS and COD
of about 82.5% and 47.5%, respectively at 45 mA/cm2 after 70
minutes by using coupled iron–aluminum electrodes. It was
demonstrated that the maximum TSS and COD removals were
obtained at some optimum experimental parameters for current
density, pH, and reaction time.
Abstract: Comparing other methods of waste water treatment,
constructed wetlands are one of the most fascinating practices
because being a natural process they are eco-friendly have low
construction and maintenance cost and have considerable capability
of wastewater treatment. The current research was focused mainly on
comparison of Ranunculus muricatus and Typha latifolia as wetland
plants for domestic wastewater treatment by designing and
constructing efficient pilot scale horizontal subsurface flow
mesocosms. Parameters like chemical oxygen demand, biological
oxygen demand, phosphates, sulphates, nitrites, nitrates, and
pathogenic indicator microbes were studied continuously with
successive treatments. Treatment efficiency of the system increases
with passage of time and with increase in temperature. Efficiency of
T. latifolia planted setups in open environment was fairly good for
parameters like COD and BOD5 which was showing reduction up to
82.5% for COD and 82.6% for BOD5 while DO was increased up to
125%. Efficiency of R. muricatus vegetated setup was also good but
lowers than that of T. latifolia planted showing 80.95% removal of
COD and BOD5. Ranunculus muricatus was found effective in
reducing bacterial count in wastewater. Both macrophytes were
found promising in wastewater treatment.
Abstract: Thin-walled elements with a matrix set on a base of
high-valuable Portland cement with dispersed reinforcement from
alkali-resistant glass fibres are used in a range of applications as
claddings of buildings and infrastructure constructions as well as
various architectural elements of residential buildings.
Even though their elementary thickness and therefore total weight
is quite low, architects and building companies demand on even
further decreasing of the bulk density of these fibre-cement elements
for the reason of loading elimination of connected superstructures
and easier assembling in demand conditions.
By the means of various kinds of light-weight aggregates it is
possible to achieve light-weighing of these composite elements.
From the range of possible fillers with different material properties
granulated expanded glass worked the best.
By the means of laboratory testing an effect of two fillers based on
expanded glass on the fibre reinforced cement composite was
verified.
Practical applicability was tested in the production of commonly
manufactured glass fibre reinforced concrete elements, such as
channels for electrical cable deposition, products for urban equipment
and especially various cladding elements.
Even though these are not structural elements, it is necessary to
evaluate also strength characteristics and resistance to environment
for their durability in certain applications.
Abstract: The Malaysian government had consistently revived
its campaign for “Buy Malaysian Goods” from time to time. The
purpose of the campaign is to remind consumers to be ethnocentric
and patriotic when purchasing product and services. This is necessary
to ensure high demand for local products and services compared to
foreign products. However, the decline of domestic investment in
2012 has triggered concern for the Malaysian economy. Hence, this
study attempts to determine the drivers of actual purchasing behavior,
intention to purchase domestic products and ethnocentrism. The
study employs the cross-sectional primary data, self-administered on
household, selected using stratified random sampling in four
Malaysian regions. A nine factor driver of actual domestic purchasing
behavior (culture openness, conservatism, collectivism, patriotism,
control belief, interest in foreign travel, attitude, ethnocentrism and
intention) were measured utilizing 60 items, using 7-point Likertscale.
From 1000 questionnaires distributed, a sample of 486 were
returned representing 48.6 percent response rate. From the fit
generated structural model (SEM analysis), it was found that the
drivers of actual purchase behavior are collectivism, cultural
openness and patriotism; the drivers of intention to purchase
domestic product are attitude, control belief, collectivism and
conservatism; and drivers of ethnocentrism are cultural openness,
control belief, foreign travel and patriotism. It also shows that
Malaysian consumers scored high in ethnocentrism and patriotism.
The findings are discussed in the perspective of its implication to
Malaysian National Agenda.
Abstract: The thermal behavior of a large-scale, phase change material (PCM) enhanced building envelope system was studied in regard to the need for pre-fabricated construction in subtropical regions. The proposed large-scale envelope consists of a reinforced aluminum skin, insulation core, phase change material and reinforced gypsum board. The PCM impact on an energy efficiency of an enveloped room was resolved by validation of the EnergyPlus numerical scheme and optimization of a smart material location in the core. The PCM location was optimized by a minimization method of a cooling energy demand. It has been shown that there is good agreement between the test and simulation results. The optimal location of the PCM layer in Hong Kong summer conditions has been then recomputed for core thicknesses of 40, 60 and 80 mm. A non-dimensional value of the optimal PCM location was obtained to be same for all the studied cases and the considered external and internal conditions.
Abstract: Meeting the growth in demand for digital services
such as social media, telecommunications, and business and cloud
services requires large scale data centres, which has led to an increase
in their end use energy demand. Generally, over 30% of data centre
power is consumed by the necessary cooling overhead. Thus energy
can be reduced by improving the cooling efficiency. Air and liquid
can both be used as cooling media for the data centre. Traditional
data centre cooling systems use air, however liquid is recognised as a
promising method that can handle the more densely packed data
centres. Liquid cooling can be classified into three methods; rack heat
exchanger, on-chip heat exchanger and full immersion of the
microelectronics. This study quantifies the improvements of heat
transfer specifically for the case of immersed microelectronics by
varying the CPU and heat sink location. Immersion of the server is
achieved by filling the gap between the microelectronics and a water
jacket with a dielectric liquid which convects the heat from the CPU
to the water jacket on the opposite side. Heat transfer is governed by
two physical mechanisms, which is natural convection for the fixed
enclosure filled with dielectric liquid and forced convection for the
water that is pumped through the water jacket. The model in this
study is validated with published numerical and experimental work
and shows good agreement with previous work. The results show that
the heat transfer performance and Nusselt number (Nu) is improved
by 89% by placing the CPU and heat sink on the bottom of the
microelectronics enclosure.
Abstract: MSMEs are regarded as the sunrise sector of the
Indian economy in view of its large potential for growth and likely
socio economic impact specifically on employment and income
generation. In today’s competitive business environment, global
competition forces companies to continuously seek ways of
improving their products and services. The pressure on organizations
to adapt to new technologies and external threats requires
resourcefulness, creativity and innovation. Market has become more
open, competitive and customers more demanding. Without
continuous technology innovation, no organization can ever remain
competitive. Innovations reflect a critical way in which organizations
respond to either technological or market challenges. The need of the
market is to deliver high quality products through continuous
changing in features in product, improve existing products, reduce
their cost, and improve employee skills, training, technology
infrastructure and financial policies. Therefore, the key factor of
organization’s ability to change is innovation. The study presents a
detailed review of literature on the role of technology innovation in
improving manufacturing performance of industries.
Abstract: Power systems are operating under stressed condition
due to continuous increase in demand of load. This can lead to
voltage instability problem when face additional load increase or
contingency. In order to avoid voltage instability suitable size of
reactive power compensation at optimal location in the system is
required which improves the load margin. This work aims at
obtaining optimal size as well as location of compensation in the 39-
bus New England system with the help of Bacteria Foraging and
Genetic algorithms. To reduce the computational time the work
identifies weak candidate buses in the system, and then picks only
two of them to take part in the optimization. The objective function is
based on a recently proposed voltage stability index which takes into
account the weighted average sensitivity index is a simpler and faster
approach than the conventional CPF algorithm. BFOA has been
found to give better results compared to GA.
Abstract: The paper deals with behaviour of the segment 50+ in
the financial market in the Czech Republic. This segment could be
said as the strong market power and it can be a crucial business
potential for financial business units. The main defined objective of
this paper is analysis of the customers´ behaviour of the segment 50-
60 years in the financial market in the Czech Republic and proposal
making of the suitable marketing approach to satisfy their demands in
the area of product, price, distribution and marketing communication
policy. This paper is based on data from one part of primary
marketing research. Paper determinates the basic problem areas as
well as definition of financial services marketing, defining the
primary research problem, hypothesis and primary research
methodology. Finally suitable marketing approach to selected sub
segment at age of 50-60 years is proposed according to marketing
research findings.
Abstract: This study estimates the seismic demands of tall
buildings with central symmetric setbacks by using nonlinear time
history analysis. Three setback structures, all 60-story high with
setback in three levels, are used for evaluation. The effects of
irregularities occurred by setback are evaluated by determination of
global-drift, story-displacement and story drift. Story-displacement is
modified by roof displacement and first story displacement and story
drift is modified by global drift. All results are calculated at the
center of mass and in x and y direction. Also the absolute values of
these quantities are determined. The results show that increasing of
vertical irregularities increases the global drift of the structure and
enlarges the deformations in the height of the structure. It is also
observed that the effects of geometry irregularity in the seismic
deformations of setback structures are higher than those of mass
irregularity.
Abstract: Housing loans play an important role in CEE
countries’ economies. This fact is based on their share in total loans
to households and their importance for economic activity and growth
in CEE countries. Therefore, it is important to find out key
determinants of housing loans demand in these countries. The aim of
this study is to research and analyze the determinants of the demand
for housing loans in Croatia. In this regard, the effect of economic
activity, loan terms and real estate prices were analyzed. Also, the
aim of this study is to find out what motivates people to take housing
loans. Therefore, primarily empirical study was conducted among the
Croatian residents. The results show that demand for housing loans is
positively affected by economic growth, higher personal income and
flexible loan terms, while it is negatively affected by interest rate rise.