Abstract: This paper compares the recent transformerless ACDC
power converter architectures and provides an assessment of
each. A prototype of one of the transformerless AC-DC converter
architecture is also presented depicting the feasibility of a small form
factor, power supply design. In this paper component selection
guidelines to achieve high efficiency AC-DC power conversion are
also discussed.
Abstract: In a chirp spread spectrum (CSS) system, the overlap
technique is used for increasing bit rate. More overlaps can offer
higher data throughput; however, they may cause more intersymbol
interference (ISI) at the same time, resulting in serious bit error
rate (BER) performance degradation. In this paper, we perform the
BER analysis and derive a closed form BER expression for the
overlap-based CSS system. The derived BER expression includes
the number of overlaps as a parameter, and thus, would be very
useful in determining the number of overlaps for a specified BER.
The numerical results demonstrate that the BER derived in a closed
form closely agrees with the simulated BER.
Abstract: A submerged horizontal plate type breakwater is
pointed out as an efficient wave protection device for cage culture in
marine fishery. In order to reveal the wave elimination principle of this
type breakwater, boundary element method is utilized to investigate
this problem. The flow field and the trajectory of water particles are
studied carefully. The flow field analysis shows that: the interaction of
incident wave and adverse current above the plate disturbs the water
domain drastically. This can slow down the horizontal velocity and
vertical velocity of the water particles.
Abstract: A study of the H-beam's nanosize structure phase
states after thermomechanical strengthening was carried out by TEM.
The following processes were analyzed. 1. The dispersing of the
cementite plates by cutting them by moving dislocations. 2. The
dissolution of cementite plates and repeated precipitation of the
cementite particles on the dislocations, the boundaries, subgrains and
grains. 3. The decay of solid solution of carbon in the α-iron after
"self-tempering" of martensite. 4. The final transformation of the
retained austenite in beinite with α-iron particles and cementite
formation. 5. The implementation of the diffusion mechanism of γ ⇒
α transformation.
Abstract: The purpose of this study is to investigate the
relationship between corporate governance and pricing for initial
public offerings (IPOs). Empirical result finds that the prediction of
pricing of IPOs with corporate governance added can have a rather
higher degree of predicting accuracy than that of non governance
added during the training and testing samples. Therefore, it can be
observed that corporate governance mechanism can affect the pricing
of IPOs
Abstract: In the meat processing industry the substitution of
meat with non-meat ingredients is considered an important strategy
for reducing overall production costs. The main purpose of the
current research was to evaluate differences in physical-chemical
composition of cooked sausage with different legumes additions.
Peas (Pisum sativum), beans (Phaseolus vulgaris) and lentil (Lens
culinaris) were used in preparation of sausages. The legumes at
proportion of 20% of the total weight of meat were added in
sausages. The whole ingredients were mixed, filled into casing,
compressed, cooked and cooled. After storage the samples were
sensory evaluated. The sensory evaluation was carried out using the
nine point hedonic scale and line scale. Sausages without legumes
flour was used as control sample. The main conclusion of the current
research the legumes flour can be successfully used for cooked
sausages production.
Abstract: This paper is concerned with an investigation into the
localized non-stability of a thin elastic orthotropic semi-infinite plate.
In this study, a semi-infinite plate, simply supported on two edges
and different boundary conditions, clamped, hinged, sliding contact
and free on the other edge, are considered. The mathematical model
is used and a general solution is presented the conditions under which
localized solutions exist are investigated.
Abstract: In this paper, we present the preconditioned mixed-type
splitting iterative method for solving the linear systems, Ax = b,
where A is a Z-matrix. And we give some comparison theorems
to show that the convergence rate of the preconditioned mixed-type
splitting iterative method is faster than that of the mixed-type splitting
iterative method. Finally, we give a numerical example to illustrate
our results.
Abstract: Micro power sources are required to be used in autonomous microelectromechanical system (MEMS). In this paper,
we designed and fabricated a three dimensional (3D) MEMS supercapacitor, which is consisting of conformal silicon
dioxide/titanium/polypyrrole (PPy) layers on silicon substrate. At first, ''through-structure'' was fabricated on the silicon substrate by high-aspect-ratio deep reactive ion etching (DRIE) method, which enlarges the available surface area significantly. Then the SiO2/Ti/PPy layers grew sequentially on the ³through-structure´. Finally, the supercapacitor was investigated by electrochemical methods.
Abstract: By means of Contractor Iteration Method, we solve and visualize the Lane-Emden(-Fowler) equation Δu + up = 0, in Ω, u = 0, on ∂Ω. It is shown that the present method converges quadratically as Newton’s method and the computation of Contractor Iteration Method is cheaper than the Newton’s method.
Abstract: The effect of a time delay on the transmission on
dengue fever is studied. The time delay is due to the presence of an
incubation period for the dengue virus to develop in the mosquito
before the mosquito becomes infectious. The conditions for the
existence of a Hopf bifurcation to limit cycle behavior are
established. The conditions are different from the usual one and they
are based on whether a particular third degree polynomial has
positive real roots. A theorem for determining whether for a given
set of parameter values, a critical delay time exist is given. It is
found that for a set of realistic values of the parameters in the model,
a Hopf bifurcation can not occur. For a set of unrealistic values of
some of the parameters, it is shown that a Hopf bifurcation can occur.
Numerical solutions using this last set show the trajectory of two of
the variables making a transition from a spiraling orbit to a limit
cycle orbit.
Abstract: In this paper, a thermal model of cast- resin dry type
transformer is proposed. The proposed thermal model is solved by
finite element technique to get the temperature at any location of the
transformer. The basic modes of heat transfer such as conduction;
convection and radiation are used to get the steady state temperature
distribution of the transformer. The predicted temperatures are
compared with experimental results reported in this paper and it is
found a good agreement between them. The effects of various
parameters such as width of air duct, ambient temperature and
emissivity of the outer surface were also studied.
Abstract: This paper proposes the method combining artificial neural network with particle swarm optimization (PSO) to implement the maximum power point tracking (MPPT) by controlling the rotor speed of the wind generator. With the measurements of wind speed, rotor speed of wind generator and output power, the artificial neural network can be trained and the wind speed can be estimated. The proposed control system in this paper provides a manner for searching the maximum output power of wind generator even under the conditions of varying wind speed and load impedance.
Abstract: Separation of propylene-propane mixture using
immobilized liquid membrane was investigated. The effect of transmembrane
pressure and carrier concentration on membrane
separation performance was studied. It was observed that for 30:70
(vol. %) propylene-propane mixture, at pressure of 120kPa and
carrier concentration of 20wt. %, a separation factor of 474 was
obtained.
Abstract: Liquid-liquid extraction is a process using two immiscible
liquids to extract compounds from one phase without high
temperature requirement. Mostly, the technical implementation of
this process is carried out in mixer-settlers or extraction columns. In
real chemical processes, chemicals may have high viscosity and
contain impurities. These impurities may change the settling behavior
of the process without measurably changing the physical properties
of the phases. In the current study, the settling behavior and the affected
parameters in a high-viscosity system were observed. Batchsettling
experiments were performed to experimentally quantify the
settling behavior and the mixer-settler model of Henschke [1] was
used to evaluate the behavior of the toluene + water system. The
viscosity of the system was increased by adding polyethylene glycol
4000 to the aqueous phase. NaCl and Na2SO4 were used to study the
influence of electrolytes. The results from this study show that increasing
the viscosity of water has a higher influence on the settling
behavior in comparison to the effects of the electrolytes. It can be
seen from the experiments that at high salt concentrations, there was
no effect on the settling behavior.
Abstract: In the article the experience of principle new
technology development of ethnopsychological experiment on the
basis of using other virtual independent experimental variables is
presented. It is shown that ethnic prejudices are the result of forming
and development of specific semantic barriers, arising up in the
conditions of interethnic co-operation and people-s communication.
Their overcoming is more successful in the conditions of the special
organized process of teaching in a polyethnic environment,
characteristic for the modern institute
Abstract: According to the European laws, there is the
possibility of reusing the washing wastes for the environmental
requalification of quarry lakes. The paper deals with the
hydrogeological aspects involved in this possibility, as the
introduction of finest wastes in the quarry lakes can generate
alterations of the hydrogeological setting of the area, and problems
for the future accessibility of the zone. To evaluate the
hydrogeological compatibility of the washing wastes reuse in quarry
lakes a groundwater numerical model was carried out, pointing out
both the hydrogeological feasibility of this intervention and some
guide lines for its optimization, in terms of inflow point with regard
the groundwater flow direction and loss of volume in the quarry lake.
Abstract: This experiment was conducted to investigate the
effect of different levels of dietary chromium yeast (Cr-yeast) on
thigh meat quality of broiler chicks reared under heat stress
condition. Two hundred and forty Ross male chickens in heat stress
condition (33±3°C) were allocated to five treatments in a completely
randomized design. Treatments were supplemented with 0 (control),
200, 400, 800 and 1200 μg kg-1 Cr in the form of Cr yeast. Twelve
chicks from each treatment were slaughtered at 42 d, to evaluate
moisture, protein, lipid, pH and lipid oxidation of thigh meat.
Protein, moisture, lipid and pH of thigh meat were not affected by
supplemental Cr. Thigh meat lipid tended to decrease in broilers
received 1200 μg kg-1. Storage time increased lipid oxidation of
meat (P
Abstract: Over recent years, the number of building integrated photovoltaic (BIPV) installations for home systems have been increasing in Malaysia. The paper concerns an analysis - as part of current Research and Development (R&D) efforts - to integrate photovoltaics as an architectural feature of a detached house in the new satellite township of Putrajaya, Malaysia. The analysis was undertaken using calculation and simulation tools to optimize performance of BIPV home system. In this study, a the simulation analysis was undertaken for selected bungalow units based on a long term recorded weather data for city of Kuala Lumpur. The simulation and calculation was done with consideration of a PV panels' tilt and direction, shading effect and economical considerations. A simulation of the performance of a grid connected BIPV house in Kuala Lumpur was undertaken. This case study uses a 60 PV modules with power output of 2.7 kW giving an average of PV electricity output is 255 kWh/month..
Abstract: In order to supplement the brittle property of concrete,
fibers are added into concrete mixtures. Compared to general concrete,
various characteristics such as tensile strength, bending strength,
bending toughness, and resistance to crack are superior, and even
when cracks occur, improvements on toughness as well as resistance
to shock are excellent due to the growth of fracture energy. Increased
function of steel fiber reinforced concrete can be differentiated
depending on the fiber dispersion, and sand percentage can be an
important influence on the fiber dispersion. Therefore, in this research,
experiments were planned on sand percentage in order to apprehend
the influence of sand percentage on the bending properties and direct
tension of SFRC and basic experiments were conducted on bending
and direct tension in order to recognize the properties of bending
properties and direct tension following the size of the aggregates and
sand percentage.